ML19261B666
| ML19261B666 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 12/30/1978 |
| From: | Glover F, Holmes H PUBLIC SERVICE CO. OF COLORADO |
| To: | |
| Shared Package | |
| ML19261B664 | List: |
| References | |
| NUDOCS 7902280369 | |
| Download: ML19261B666 (125) | |
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FORT ST. VRAIN NUCLEAR GENERATIriG STATI0il ECOLOGICAL MONITORING PROGRA!1 Progress Report for the Period July 1,1978 to December 31, 1973 Prepared by:/s/ 0 45 [ ed A. Glovfr, Project Director, Thorne
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9 __ / /22 /77 7Date O by:/s/ W. - l/21/79 e iluclear PreJect Department Date e O O
Progress Report July 1, 1978 to December 31, 1978 ECOLOGICAL MONITORING FORT ST. VRAIN NUCLEAR GENERATING STATION for Public Service Company of Colorado by Thorne Ecological Institute 2336 Pearl Boulder, Colorado Dr. Fred A. Glover Project Director 9
TABLE OF CONTENTS Page Summary . ................... ...... .. .. I Introduction ......... . .... .......... 6 Investigator Reports ....... ... ..... ...... 8 Aquatic Section . .. ........ .. . .. 9 Invertebrates and Fish ........... . ... 10 Algae . . . . . . . . . ......... ... 40 Avian Section ..... .. .... .. ........ 62
- Terrestrial Section ....... ..... ...... . 73 Vegetation ' Monitoring . ........ . . ..... 74 Irrigated Pasture Monitoring ....... .. .... 84 O Ecophysiological Characteristics ............ 92 Mammals, Amphibians, and Reptiles . . . . . ...... 103 Invertebrates . . . . . . . . . . . . . . . . . . . . . . 115 O
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SUMMARY
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2 General Summary The non-radiation, environmental monitoring data presented in this report continue to indicate only minor variations in the environ's eco-systems and trophic levels. Generilly, environmental quality is 'eing maintained. To date, no discernible nor measurable harmful environmental response has become evwnt through the monitoring program from operation of the Station. Aquatic Section Invertebrates Significantly more aquatic macroinvertebrate taxa were collected from all stations in 1978 than in 1977. The typically common species were about the same ones as in the past. Fish A total of 2131 fish was collected from two sampling stations. Fif teen species were represented and tha collection was not particularly different from previous years. No game fish were collected. Algae O Algae exhibited the sam patterns of dominance and population dynamics as in previous years. A total of 157 species was collected and identified, similar to 1977. This number represents a low species O diversity. Physical factors were the apparent major causes of popula-tion shifts and changes. , Avian Section Based on seven years of population trend data, summer, fall, and winter populations have fluctuated widely and no trend is apparent. O
O 3 Spring populations of birds show a fairly distinct pattern of overall 9 decline in 1973 followed by a steady recovery to 1977 and a slight decline in 1978. Terrestrial Section g Vegetation Most vegetation differences that occurred in 1978 relative to 1977 probably resulted from different weather conditions, insect herbivory, (p and phenological stage at the time of sampling. Irrigated Pasture Monitoring O Most of the soil chemicals differed across the pasture in 1978, some might be inherent but others were induced by chemical treatment. Organic matter differences occurred only in September. O Ecophysiological Characteristics Leaf injury for kochia appeared to be slightly greater near the Generating Station but for the other two species leaf injury was more e related to microclimate, site, and species differences. Mammals, Amphibians, and Reptiles O With only minor changes in species abundance and locations, the same manmals, amphibians, and reptiles noted in the inventory phase of the project are preser,t. Some of the small mammal populations have e showed yearly fluctuations. Invertebrates The mud-loving beetles, caddis flies, spiders, and Collembola appear e to be remaining relatively stable. The shortage of food for the past few 0
. 4 years has created a substantial decline in the Carrion Beetle. Ants have shown an increase in 1978 over 1977 but much of this increase was the result of large increases recorded from one sampling transect.
5 FORT ST. VRAIN Generation Suimiary - 1978 8 Dates with tiumber of Gross Electric Days Without Generation Montn Generation Generation MWH 4 January 13-23 20 34,290 February 0 28 0 March 0 31 0 4 April 4-19, 21-30 4 65,d50 May 1-8, 10-26, 2 99,073 28-31 June 1-6, 12-29 6 98,459 8 July 3-14, 17-31 5 85,839 August 18, 19, 21-31 18 14,496 September 1-8 23 25,147 8 October 5-12, 14-17, 31 18 24,880 lloveraber 1-29 1 110,594 December 9-31 8 92,583 8 9 O O O
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7 Introduction This progress report presents non-radiological, environmental monitoring information and activities for the period January 1,1978 to December 31, 1978. Environmental studies have been conducted on the St. Vrain Site environs since 1971. O 9 9
8 INVESTIGATOR REPORTS O
3 AQUATIC SECTION
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10 A0 VATIC ItWERTEJRATE AND F'SH MONITORING by Clarence A. Carlson David L. Propst Michael A. Carnevale W. Don Fronk O O
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11 INTRODUCTION Monitoring of the aquatic biota in the area of the Fort St. Vrain Nuclear Generating Station in 1978 was conducted by Graduate Assistants Michael A. Carnevale (January through May 1978) o,id David ' Propst (June through December 1978). Data resulting from analysis of timed collections of macroinvertebrates from the natural substrates and fish collections made in October and November are the primary components of this report. STUDY AREA DESCRIPTION Stations SP4B and Cl were described by Cressey, Carlson and Fronk (1974). Station SP4U was described by Stacey, Carlson and Frank (1975). Station SP4A was described by Carlson et al. (1977). Sampling s o?tions for aquatic macroinvertebrates and fishes are illustrated in Figure 1. Both outlets of Goosequill Pond had intennittent discharge in the first 6 months of 1978 and constant discharge in the last 6 months. Channel alteration in the South Platte River was apparent throughout the year. Fishes were collected at stations SV2 and SV5 on the St. Vrain River and at SP4B and immediately below the intake on the South Platte River. The upstream fish-sampling station was moved to the intake area because high discharge prevented adequate sampling at the original sampling site. METHODS Macivinvertebrate samples were collected by methods described by Eder, Carlson and Fronk (1974). The samples were composed of macro-invertebrates collected in 10-min samples (with a triangular dipnet) O
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13 combined with 5 min of debris picking. Physical and chemical parameters were determined according to methods described by the American Public Health Association (1971), with the exception of total hardness. Total hardness determinations were made by use of a Hach Water Chemistry Kit (Model AL-36B). Determination of dissolved solids was added to the list of chemical tests conducted in June 1978 and was done according to standard Methods (APHA 1971). Other equipment used included a mercury ther-mometer, a Hach turbidimeter, a Beckman conducting bridge and a Corning pH meter. O RESULTS SP4A O Forty-four aquatic macroinvertebrate taxa were collected from Station SP4A in 1978 (Table 1). Oligochaetes were the most abundant organism, comprising 47.4 percent of total organisms collected.
- Cricotopus sp. (Diptera: Chironomidae) was second in abundance (15.9 percent). Simulium sp. (Diptera: Simulidae) and Paralauterborniella sp. (Diptera: Chironomidae) were also present in relatively large O numbers (7.2 and 4.8 percent, respectively). Baetis sp. (Ephemeroptera:
Baetidae) and Hydropsyche sp. (Trichoptera: Hydropsychidae) were the most common non-dipteran aquatic insects collected (3.4 and 3.6 per-O cent,respectively). Several unusual aquatic macroinvertebrates were collected at SP4A in 1978. Perlodidae (Plecoptera), Ochrotrichia sp. (Trichoptera: Hydroptilidae), Ephydridae (Diptera) and Copepoda were ' among the unusual organisms collected. Cricotopus sp. and oligochaetes tended to be most abundant from June through November (Figures 2 and O
14 9 Table 1. Total organisms collected at Stations SP4A, SP4U, SP4B, and Cl from January through December 1978. 9 Station Organism SP4A SP4U SP4B Cl Total 9 Hypogustruridae l 1 Baetis sp. 595 1063 293 270 2221 Heptagenia sp. 19 34 8 24 85 .Tricorythodes sp. 5 82 4 47 138 Siphlonurus occidentalis 8 1 9 Ischnura sp. I 10 10 21 $ Argia sp. 34 1 2 3 40 Amphiagrion sp. 1 1 Enallagma sp. 1 2 2 5 Ophiogomphus sp. I 1 Perlodidae 8 1 9 Hemiptera 1 1 S Corixidae 1 1 Cenocorixa sp. 11 1 12 Tricorixa sp. 16 16 Lampyridae 1 1 Dytiscidae 17 1 18 Dytiscidae larvae 1 1 9 Rhantus sp. 8 1 9 [te_1_ophorus sp. 1 1 2 Agabetes sp. 2 2 .Laccophilus sp. 1 1 Tricoptera pupae 8 8 flydropsyche sp. 630 225 183 137 1175 9 Ochrotrichia sp. 71 70 55 44 240 Kgraylea sp. 2 1 1 4 Tabanidae 1 1 Ephydridae 2 8 10 Brachydeutera sp. I 1 Palpom e sp. 9 9 18 9 Tipulidae 224 72 32 28 356 Tjyula sp. 48 8 1 57 Hexatoma sp. 16 16 Muscidae 10 32 33 75 Simulidae pupae 52 65 35 18 170 Simulium sp. 1284 1446 758 557 4045 9 Chironomidae 846 51 7 116 88 1567 Chironomidae pupae 399 646 168 169 1382 Cricotopu_s_ sp. 2809 3835 616 939 8199 Chironomus sp. 490 540 445 135 1610 Dicrotendipes sp. 92 140 144 30 406 Diplocladius sp. 1 1 9 Conchapelopia sp. 158 56 17 d 254 Phaenopsectra sp. 1 1 Polyfedilum sp. 208 185 69 34 496 0
15 Table 1. Continued. Station Organism SP4A SP4U SP4B Cl Total Psectrocladius sp. 2 8 9 1 20 Diamesa sp. 11 45 20 11 87 Cryptochironomus sp. 24 8 32 Tanytarsus sp. 8 8 9 25 Paralauterborniella sp. 848 1568 1312 529 4257
.Pseudochironomus sp. 8 8 32 48 Tanypus sp. 8 8 f40nodiamesa sp 1 1 Thienemanniella sp. 8 8 Parachironomus sp. 2 2 Rheotanytarsus sp. 8 17 144 169 Glyptotendipes sp. 81 58 3 16 158 Stictochironomus sp. 8 16 24 Hydroida 67 52 119 Oligochaeta 8370 7168 2128 2871 20537 Hiradinea 9 9 Erpobdellidae 8 8 Planaridae 9 2 11 Copepoda 8 8 Cyclopidae 1 1 Ostracoda 6 6 Daphnidae 8 8 Hyalella azteca 221 167 185 128 701 Crangonyx sp. 2 2 1 5 Asellus sp. 2 8 29 39 Cambarus sp. 2 1 1 4 Physa sp. 9 8 23 10 50 Lymnaea sp. 1 1 Total 17653 18147 6780 6453 49033 9
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17 7). Chironomus_ sp. (Diptera: Chironomidae) were most common from June through October (Figure 3). In contrast, Baetis sp. was most abundant from May through June; Hydropsyche sp. was more common in January, February, October and November (Figures 4 and 5), and Simulium sp. was relatively abundant from January through May and November through December (Figure 6). SP4U Forty-four aquatic macroinvertebrate taxa were collected from Station SP4U in 1978 (Table 1). Oligochaete:. were the most common organism (39.5 percent) collected. Cricotopus sp. was quite abundant, representing 21.1 percent of the organisms collected. Paralauter-borniella sp., Chironomus sp. and Simulium sp. were also common eipterans (8.6, 3.0 and 8.0 percent of collections, respectively). Baetis sp. O and Hydropsyche sp. were the most common non-dipteran aquatic insects (5.9 and 1.2 percent, respectively). Hyalella azteca was second in abundance (0.9 percent) among non-insect taxa collected at SP4U in 9 1978. Perlodidae, Ochrotrichia sp., Stictochironomus sp., Erpobdellidae and Daphnidae were among tile unusual organisms collected at SP4U in 19/8. Cricotopus sp., Chironomus sp. and oligochaetes were most common O from June through October (Figures 2, 3 and 7). Baetis sp. was most abundant from August through October (Figure 4). Hydropsyche sp. was more common from January to April and in October and November (Figure O 5). Simulium sp. was least common from June through early September (Figure 6). O SP4B Forty-two aquatic macroinvertebrate taxa were collected from Station SP4B in 1978 (Table 1). Total numbers (6780) collected were significantly O
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21 lower than numbers collected at SP4A or SP4U (17,653 and 18,147, respectively). Oligochaetes were the most abundant organisms (31.4 percent) collected at SP4B in 1978. Paralauterborniella sp. was second in abundance (19.4 percent). Simulium sp., Cricotopus sp. and and Chironomus sp. constituted the major portion of the aquatic macro-invertebrate community at SP4B (11.2, 9.1 and 6.6 percent, respectively). Baetis sp. , hydropsyche sp. nd Hyalella azteca were the most common aquatic macroinvertebrates exclusive of the oligochaete and dipteran components (4.3, 2.7 and 2.7 percent, respectively). Hypogustruridae (Collembola), Ochrotrichia sp., Monodiamesa (Diptera: Chironomidae), Hvdroida, Cyclopidae and Ostracoda were among the unusual aquatic macroinvertebrates collected. Cricotopus sp. was most common from late June through early October (Figure 2). Chironomus sp. was rather uncommon throughout the year (Figure 3). Oligochaetes were generally more common from the end of May through December (Figure 7). Baetis sp. was most common in late summer (Figure 4). Hydropsyche sp. was only common in late October and early November (Figure 5). Simulium sp. was common early i: the year and in late November (Figure 6). Cl Forty-six aquatic macroinvertebrate taxa, the most collected at any station, were collected at Station Cl in 1978. Despite the large number of taxa, the fewest organisms were collected at C1 (6453) (Table 1). Oligochaetes were the most common organism (44.5 percent), and Cricotopus sp. was second in abundance (14.6 percent). Simt.lium sp. and Paralauterborniella sp. were alsn common (8.6 and 8.2 percent, respectively). Baetis sp., Hydropsyche sp. and Hyalella azteca were the most common non-oligochaete or non-dipteran components of the aquatic
O 22 macroinvertebrate community (4.2, 2.1 and 2.0 percent, respectively). Lampyridae (Coleoptera), Ochrotrichia sp., Epaydridae, Phaenopsectra g sp. (Diptera: Chironomidae), Stictochironomus sp. and Lymnaea sp. were araong the unusual aquatic macroinvertebrates collected at Cl in 1978. Cricotopus sp. was most common from early August through early g October (Figure 2). Chironomus sp. occurred in rather low numbers throughout the year (Figure 3). Baetis sp. was only abundant in late August (Figure 4). Hydropsyche sp. was generally most common in late g February, late August, October and late November (Figure 5). Simuliun sp. was more common in early 1978 and in late November and December (Figure 6). Oligochaetes were morc common from late August to late e November (Figure 7). Fish Collections O A total of 2131 fish were collected from two sampling stations on the South Platte River and two sampling stations on the St. Vrain River. Fifteen species of fish were in the collections. Station SV5 9 had the greatest number of species (13) and the largest number of individuals (795) of the stations sampled. Station SP4B had the fewest species (9) and individuals (127). Notropis stramireus was the most 4 common species at all stations (Tables 2, 3, 4 and 5). Pimephales promelas was common at all sites. Cyprinus carpio and Catostomus spp. comprised the bulk of the biomass of fishes at all sampling statione. 9 Fundulus kansae were relatively common at the South Platte intake, SP4B and SV2. Hybognathus hankinsoni and Culea inconstans were unexpected species at several stations. No game fish were collected at any O sampling station. Chemical and Physical Data Chemical and physical data for Stations SP4A, SP4U, SP4B and Cl e
23 Table 2. Number and mean length and weight of ichthyofauna collected at South Platte intake on 16 November 1978. An asterisk indicates that mean values are based on a subsample of the specimens collected. The subsample number is in parentheses. Species N T(mm) U(gm) Notropis stramineus* 344(3:9) 51.05 1.49 Notropis dorsalis
- 32(25) 61.72 1.84 Notropis lutrensis 1 56.00 2.35 Pimephales promelas* 185(58) 46.10 1.29 Rhinichthys cataractae 1 Campostoma anomalum 5 Cyprinus carpio 8 Catostomus catostomus 1 g Catostomus commersonl* 2(1) 90.00 9.22 Fundus kansae* 28(1) 57.00 1.93 Total 607 9
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24 O Table 3. Number and mean length and weight of ichthyofauna collected at SP4B on 28 October 1978. An asterisk indicates that mean values are based on a subsample of the specimens collected. gp The subsample number is ., parentheses. Species N T(mm) E(9) O Notropis stramineus 44 57.91 2.05 Notropis lutrensis* 5 55.40 2.69(2) Pimephales promelas 32 58.19 9 Cyprinus carpio 15 147.87 163.33 Catostomus catostomus 2 87.5 7.46 Catostomus commersoni 2 63.0 0 Fundulus kansae '5 63.2 Lepomis cyanellus 1 79.00 Lecomis cyanellus x 1 79.00 1.47
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25 Table 4 Number and mean length and weight of ichthyofauna collected at SV5 on 28 October 1978. An asterisk indicates that mean values are based on a subsample of the specimens collected. The subsample number is in parentheses. Species N l(mm) W(g) Notropijl dorsalis 10 81.5 2.96 Notropis stramineus* 431(250) 50.19 1.34 Notropis lutrensis 9 41.22 1.02 Pimephales promelas* 231(81) 57.73 2.00 Rhinichtg_s_cataractae* 15(4) 48.75 1.22 Hybognathus hankinsoni 5 73.8 4.60 Campostoma anomalum 4 77.75 5.58 Cyprinus carpio 14 72.36 5.84 Catostomus catostomus 1 70.00 3.775 Catostomus commersoni* 42(31) 108.71 32.66 Fundulus kansae 1 78.00 8.00 Culea inconstans 2 67.00 2.00 Lepomis cyanellus 12 68.58 8.17 Total 795
26 O Table 5. Number and mean length and weight of ichthyofauna collected at SV2 on 4 November 1978. An asterisk indicates that mean values are based on a subsample of the specimens collected. g The subsample number is in parentheses. Species N 1(mm) U(g) O Notropis dorsalis. 5 61.8 1.99 Notropis stramineus* 508(29) 59.34 2.09 Notropis lutrensis* 5(4) 58.25 2.12 , Pimephales promelas 19 53.74 1.97 Semotilus_atromaculatus 1 170 56.00 Rhinichthys cataractae 3 46.00 1.02 , Hybognathus hankinsoni 4 72.00 4.43 Cypr_i rm s. ca rpi o* 12(11) 236.64 358.33 Catostomus,catostomus 1 232.00 132.00 , Catostomus commersoni* 21(18) 139.72 69.30 Fundulus kansae* 22(3) 54.00 1.61 Lepomis cyanellus 1
,
Total 602 6 6 9 e
S Table 6a. Summary of chemical and physical data for Station SP4A, January through June 1978. 1978 Date Parameter 1/12 1/28 2/5 2/19 3/11 3/22 4/11 4/22 5/13 5/20 6/12 6/23 Air Temp. (C) 8.0 -7.0 -3.0 4.0 13.0 8.5 19.5 22.0 19.5 26.0 27.0 29.0 Water Temp. (C) 2.0 1.5 1.0 2.5 6.0 5.0 9.5 17.5 20.5 2?.5 19.5 21.0 Dissolved 02 (mg/1) 7.0 7.2 7.4 7.1 7.1 6.8 8.4 7.4 7.0 6.9 5.9 7.5 Dissolved CO2 (mg/1) 22.0 50.0 15.0 15.0 34.0 160.0 60.0 45.0 42.0
- pH 7.5 7.2 7.5 7.7 7.9 7.6 7.0 7.3 7.1 7.4
- 8.3 Tot. Alkalinity (mg/1) 340 290 560 290 460 580 720 570 320 600
- 68 Filt. Solids (mg/1) 109 440 648 392 400 368 232 368 456
- Dissolved Solids (mg/l) (January - June: Test not performed prior to July)
Tot. Hardness (mg/l) 357 357 391 391 340 357 323 323 374 374 325 257 Cond. (micrombos/cm) 460 350 2300 3300 2600 2900 225 155 160 190
- 3800 Turbidity (JTU) 8.0 15.0 6.0 10.0 11.0 10.0 31.0 5.0 18.0 6.0
- 15.0
- Laboratory accident due to ,,iishandling.
Table 6b. Sunuary of chemical and physical data for Station SP4A, .1uly through December 1978. 1978 Date Parameter 7/11 7/26 8/4 8/24 9/7 9/23 10/8 10/26 11/9 11/14 12/12 Air Temp. (C) 33.0 26.0 22.0 30.0 24.0 24.5 24.0 12.5 20.0 4.0 5.0 Water Temp. (C) 23.5 21.0 18.5 20.5 21.0 17.5 17.0 12.5 13.0 3.0 2.0 Dissolved 02 (mg/l) 6.2 6.5 6.4 7.2 8.1 7.8 8.5 7.4 5.4 14.9 9.0 Dissolved CO2 (mg/l) 7.5 16.0 11.5 21.0 12.5 35.0 12.5 30.0 15.5 75.0 125.0 pH 7.7 7.5 7.6 7.4 7.6 7.2 8.0 7.6 7.5 7.3 7.1 Tot. Alkalinity (mg/1)' 223 283 245 315 279 300 660 560 232 575 588 $ Filt. solids (mg/1) 390 472 272 760 592 810 480 608 608 720 656 Dissolved Solids (mg/1) 570 688 928 830 716 814 828 790 742 842 812 Tot. Hardness (mg/1) 257 342 274 377 360 377 377 308 342 436 291 Cond. (micrombos/cm) 690 305 490 390 430 400 380 390 445 380 700 Turbidity (JTU) 17.0 2.5 150.0 3.0 4.0 8.5 4.0 19.0 15.0 10.0 49.0 9 9 9 9 9 9 9 e e e e
9 Table 7a. Summary of chemical and physical data for Station SP4U, January through June 1978. 1978 Date Parameter 1/12 1/28 2/5 2/19 3/11 3/22 4/11 4/22 5/13 5/20 6/12 i/23 Air Temp. (C) 8.0 -8.0 -2.0 5.0 12.0 8.0 20.5 23.5 19.5 25.5 25.5 29.0 Water Temp. (C) 2.0 2.0 1.0 2.0 5.0 5.5 9.5 17.0 20.5 21.0 17.0 20.0 Dissolved 0; (mg/l) 7.0 7.3 7.4 7.1 7.2 6.9 8.5 7.5 7.0 7.0 6.7 8.3 Dissolved CO2 (mg/1) 22.0 32.0 12.0 14.0 36.0 130.0 58.0 39.0 45.0
- pH 7.5 7.4 7.7 7.8 7.8 7.6 7.1 7.3 7.2 7.4 6.8 8.5 Tot. Alkalinity (mg/l) 340 280 540 280 460 560 770 550 340 620 80 72 5 Filt. Solids (mg/1) 109 536 856 336 568 656 256 464 552
- Dissolved 5 lids (mg/1) (January - June: Test not performed prior to July)
Tot. Hardness (mg/l) 357 357 391 391 357 357 323 331 374 374 342 274 Cond. (micromhos/cm) 460 410 2400 3100 2350 270D 225 150 175 185 4650 2850 Turbidity (JTU) 8.0 15.0 7.0 11.0 7.0 11.0 30.0 6.0 17.5 7.0 9.0 20.0
- Laboratory accident due to mishandling.
.
Table 7b. Surmlary of chemical and physical data for Station SP4U, July through December 1978. 1978 Date Parameter 7/11 7/26 8/4 8/21 9/7 9/23 10/8 10/26 11/9 11/24 12/12 Air Temp. (C) 31 28 21.5 30.0 24.0 24.5 24,0 9.0 17.0 3.5 5.0 Water Temp. (C) 23 18.5 18.0 19.0 21.0 17.0 17.0 9.0 12.0 4.0 2.0 Dissolved 02 (mg/l) 6.4 6.4 5.9 7.0 7.8 7.8 8.3 7.4 5.2 13.9 7.7 Dissolved C02 (mg/1) 6.0 13.5 10.5 19.0 11.0 28.0 6.8 31.0 7.5 58.0 85.0 pH 7.8 7.6 7.6 7.5 7.7 7.3 8.3 /.6 7.9 7.4 7.3 Tot. Alkalinity (mg/l) 21.8 285 222 328 302 283 742 570 274 550 614 5 Filt. Solids (mg/1) 407 576 272 744 544 744 528 584 618 680 608 Dissolved Solids (mg/1) 504 712 930 838 776 804 846 785 792 344 816 Tot. Hardness (mg/l) 274 360 274 394 360 360 '47 7 398 342 411 274 Cond. (micrombos/cm) 590 460 475 760 410 365 310 400 385 440 620 Turbidity (JTU) 18 2.5 17.5 6.5 5.5 8.2 4.0 23.0 17.5 8.0 41.0 8 9 # # e S e e e e e
e G S 9 9 9 9 9 8 e 9 i Table 8a. Summary of chemical and physical data for Station SP4B, January through June 1978. _ 1978 Date Parameter 1/12 1/28 2/5 2/19 3/11 3/22 4/11 4/22 5/13 5/20 6/12 6/23 Air Temp. (C) 7.0 -7.0 -4.0 7.0 10.0 8.5 19.0 22.5 18.5 27.5 21.0 28.0 Water Temp. (C) 2.0 2.0 0.5 2.0 5.0 5.5 10.0 17.5 21.0 22.5 15.5 19.0 Dissolved 02 (mg/l) 7.0 7.4 7.4 7.2 7.3 6.9 8.4 7.5 7.0 6.9 6.6 7.5 Dissolved CO2 (mg/i) 20.0 50.0 14.0 17.0 36.0 150.0 57.0 36.0 40.0
- pH 7.6 7.3 7.5 7.8 7.8 7.6 7.0 7.3 7.2 7.4 6.8 8.3 Tot. Alkalinity (mg/1) 310 280 E60 280 480 560 680 540 320 590 86 80 ES Filt. Solids (mg/1) 122 408 744 408 464 632 168 576 624
- Dissolved Solids (mg/1) (January - June: Test not performed prior to July)
Tot. Hardness (mg/1) 408 357 274 408 357 357 323 323 374 374 342 308 Cond. (micromhos/cm) 440 360 2400 3200 2500 2800 235 140 165 185 4000 4500
'urbidity (JTU) 6.0 12.0 6.0 10.0 E.0 10.0 30.0 5.5 18.0 6.0 12.5 9.0
. _ .
- Labor,2 Lory accident due to mishandling.
Table 8b. Summary of chemical and physical data for Station SP4B, July through December 1978.
..
1978 Date Parameter 7/11 7/26 8/4 8/24 9/7 9/23 10/_8 10/26 11/9 11/24 12/12 Air Temp.(C) 31 26.0 16 24.5 27.0 24.5 30.5 11.0 22.0 6.0 9.0 Water Temp. (C) 23 17.5 16 18.0 17.5 17.0 17.0 10.0 12.0 5.5 2.5 Dissolved 02 (mg/1) 6.4 6.3 5.8 6.5 7.' 7.6 9.8 7.0 5.3 16.2 7.5 Dissolved CO2 (mg/1) 4.6 13.0 8.5 5.5 11.0 9.5 9.5 30.0 9.5 47.0 76.0 pH 7.9 7.6 7.7 8.0 7.7 7.5 8.1 7.6 7.8 7.5 7.3 Tot. Alkalinity (mg/1) 204 275 219 311 285 157 632 566 290 (18 606 U Filt. Solids (mg/l) 341 536 368 728 560 768 560 640 600 704 640 Dissolved Solids (mg/l) 468 734 680 846 788 822 834 790 824 842 332 Tot. Hardness (mg/1) 257 360 274 377 360 360 411 308 360 436 342 Cond. (micrombos/cm) 650 380 480 490 450 270 330 380 340 430 740 Turbidity (JTU) 9 3.0 14.0 8.7 4.0 8.7 3.5 16.5 10.0 8.0 42.0 e e e e e e e e e e e
O O O O O O O Table 9a. Summary of chemical and ohysical data for Station Cl, January through June 1978. 1978 Date Parameter 1/12 1/28 2/5 2/19 3/11 3/22 4/11 4/22 5/13 5/20 6/12 6/23 Air Temp. (C) 7.2 -5.0 -3.0 7.0 12.0 8.0 19.0 22.0 29.0 21.5 28.0 Water Temp. (C) 2.0 0.5 0.5 2.0 5.5 6.0 10.0 16.0 21.5 17.5 18.5 Dissolved 02 (mg/1) 7.0 7.3 7.5 7.1 7.2 6.8 8.2 7.9 7.4 7.1 6.2 5.8 Dissolved CO2 (nig/1) 20.5 40.0 14.0 16.0 50.0 155.0 31 .0 50.0
- pH 7.6 8.0 7.6 7.8 7.8 7.4 7.0 7.6 7.4 7.3 7.1 8.2 Tot. Alkalinity (mg/l) 290 260 580 280 490 540 710 620 400 560 52 66 Filt. Solids (mg/l) 98 648 928 568 520 512 336 552 752
- Dissolved Solids (mg/1) (January - June: Test not perfonned prior to July)
Tot. Hardness (mg/l) 384 374 408 391 340 374 340 340 382 408 257 257 Cond. (micrombos/cm) 420 340 2900 3100 2400 3200 230 155 195 180 3800 2750 Turbidity (JTU) 6.0 13.0 8.0 10.0 8.0 11.0 29.0 11.0 28.0 38.0 42.5 18.0 _
- Laboratory accident due to mishandling.
Table 9b. Summary of chenical and physical data for Station C1, July through December 1978. 1978 Date Parameter 7/11 7/26 8/4 8/24 9/7 9/23 10/8 10/26 11/9 11/24 12/12 Air Temp. (C) 31 29.0 18.0 24.5 24.0 27.0 26.0 10.0 70.5 7.5 6.0 Water Temp. (C) 22.5 20.5 19.0 20.0 20.0 18.0 17.5 9.0 11.5 6.0 0.5 Dissolved 02 (mg/1) 6.6 6.3 5.8 6.6 7.6 8.0 8.9 7.5 5.7 11.3 8.0 Dissolved CO2 (mg/l) 5.0 9.0 12.5 5.5 9.0 10.5 7.5 40.0 14.5 64.0 49.0 pH 7.9 7.8 7.5 8.0 7.8 7.7 8.2 7.5 7.7 7.4 7.4 Tot. Alkalinity (mg/1) 214 320 215 307 311 285 654 580 338 658 430 Filt. Solids (mg/1) 339 280 360 584 584 678 640 620 640 664 680 Dissolved Solids (mg/1) 458 954 690 916 824 852 858 798 778 826 808 Tot. Hardness (mg/l) 240 394 257 479 377 377 360 325 360 445 325 Cond. (micrombos/cm) 605 330 440 380 405 320 300 410 385 480 650 Turbidity (JTU) 16 15.0 180 17.5 6.0 8.2 5.0 24.5 22.0 8.0 51.0 _
- 9 9 9 9 9 9 8 9 e e
35 for January through December 1978 are presented in Tables 6, 7, 8 and 9 respectively. Statistical Analysis A FORTRAN IV program (ECODIV) developed by Galat, Keefe and Bergersen (1974) was used to analyza aquatic macroinvertebrate data for 1978. Three diversity indices were computed for this analysis: Equitability (EQUIT), i.he Trophic Condition Index (TCI') and the Shannon Diversity Index (DBAR). Data are reported for each quarter of 1978 (Table 10). TCI' values were consistently lower than those reported for 1977 (in a special report submitted 11 April 1978) but remained higher than those reported for 1976 (Rohrer et al. 1977). DBAR values were higher than 1977 levels except during the last quarter of 1978. EQUIT values were generally lower than 1977 levels, except during the first quarter of 1978, but changed less than DBAR and TCI' values. The increase in DBAR values and the decrease in TCI' values indicate some improvement in water quality between 1977 and 1978 but may be due to year-to-year variations in abundance or changes in sampling wi'.h changes in student personnel. DBAR values for 1978 were generally indicative of only moderata pollution. We await further data collection before pronouncing judgment on long-term trends. DISCUSSION Significantly more aquatic macroinvertebrate taxa were collected from all stations in 1978 than in 1977. Most of the additional taxa were represented by a few individuals collected only once or twice. However, Ochrotrichia sp. was commonly collected, although in generally low numbers, through the second-half of 1978. This does not mean that
36 O Table 10. Quarterly summary of EC00Iv indices for four stations on the South Platte River, 1978. e January through March,1978 SP4U SP4A SP4B Cl TCI' .8627 .8131 .5709 .5956 $ DBAR 2.3098 2.5081 2.1763 2.3429 EQUIT .4780 .5558 .5021 .4898 e April through June, 1978 SP4U SP4A _SP4B Cl TCI' .2416 .2966 . ?.600 .3289 0 DBAR 1.4814 1.7825 2 4145 2.1218 EQUIT .1526 .1935 .3814 .2894 July through September, 1978 g SP4U SP4A SP4B Cl TCI' .6895 .5816 .8304 .7247 DBAR 2.7574 2.5750 2.6809 3.0598 e EQUIT .3914 .2922 .3283 .4057 October through December,1978 e SP4U SP4A _SP4B Cl TCI' .6467 .5936 .7468 .4619 DBAR 2.8844 2.7995 3.3137 2.5122 e EQUIT .4131 .4214 .5675 .3122 e e
37 Ochrotrichia has recently invaded the area. Rather, it probably has always occurred in the vicinity of the Fort St. Vrain Nuclear Generating Station and its case, which closely resembles small seed pods, was over-looked in previous years. At least some of the unusual organisms were present at one or several sampling sites because of the rather unusual discharge patterns of the South Platte and St. Vrain Rivers occurring in 1978. Several uncommon crustaceans were collected in 1978. Their dimunitive size probably accounts for the lack of previous reports of these taxa. No immediate explanation for the large number of taxa collected in 1978 is apparent. Channel alterations continued throughout 1978 and were augmented by the unseasonal high discharges. Channel alteration and unseasonal high discharges may account for the relatively low numbers of aquatic macroinvertebrates collected at Stations SP4B and C1. At these Stations, the substrate was monotonous and less organic debris was present than at other stations. Although the number of fish species collected at each station did not change significantly, there was some change in the species present. No game species were collected in 1978, and this is certainly a reflec-tion of the relativ-'y poor quality of the South Platte and St. Vrain Rivers. Several (Hybognathus hankinsoni, Notropis dorsalis, and Culea inconstans) which had not been reported previously were collected in 1978. Hybognathus hankinsoni and Culea inconstans were not common, thus their occurrence in 1978 does not necessarily represent a significant alteration in the ichthyofauna of the South Platte or St. Vrain Rivers. Notropis dorsalis is extremely difficult to distinguish from Notropis stramineus in the field, and it has probably always occurred
38 at the various sampling stations. An int' resting increase in the number of Fundulus kansae was noted in 1978. These fish were rather rare in 9 previous years. No immediate explanation is apparent, but they are extremely abundant in the lower South Platte River. Constant flow regimes over the past 50-75 ye 's in the South Platte River may have 4 enabled them to invade and inhabit more upstream reaches than they did historically. Culea inconstans is probably in the sampling area because of bait-bucket transfer from their more eastern, historical range. G 9 9 6 9 0 9 0
39 LITERATURE CITED American Public Health Association. 1971. Standard methods for the examination of water and wastewater. 13th ed. American Public Health Association, Washington, D.C. 847 pp. Carlson, C. A., W. D. Fronk, D. L. Propst, R. L. Rohrer, and P. E. S ta cey. 1977. Aquatic invertebrates component, Fort St. Vrain Ecological Investigations. 1977 Semi-annual Report. Report to Thorne Ecological Institute. 23 pp. Cressey, S., C. Carlson, and W. D. Frank. 1974. Aquatic invertebrate component, Fort St. Vrain Ecological Investigations. 1974 Annual Report. Report to Thorne Ecological Institute. 17 pp. mimeo. Eder, S., C. Carlson, and W. D. Frank. 1974. Final report, aquatic invertebrate component and fish food habits component, Fort St. Vrain Ecological Investigations. Report to Thorne Ecological Institute. 80 pp. mimeo. Galat, D. L., T. J. Keefe, nd E. P. Bergersen. 1974. Ecodiv-A Fortran IV Program to calculate biological iridices and bivariate statis-tical analysis methodology for evaluation of water quality. Thorne Ecological Institute Technical Publication Number ll. 70 pp. Galat, D. L., and W. J. McConnell. 1974. A quantitative baseline inventory of the aquatic macroinvertebrates and periphyton comunities of the South Platte and St. Vrain Rivers, Fort St. Vrain Nuclear Generating Station. Report to Throne Ecological Institute. 188 pp. Rohrer, R. L., P. E. Stacey, C. A. Carlson and W. D. Fronk. 1977. Aquatic invertebrate component, Fort St. Vrain Ecological Inves-tigations. 1976 Annual Report to Thorne Ecological Institute. 38 pp. Stacey, P. E., C. A. Carlson, and W. D. Frank. 1975. Aquatic inverte-brates component, Fort St. Vrain Ecological Investigations. 1975 Semi-annual Report. Report to Thorne Ecological Institute. 21 + viii pp.
40 ALGAL f10rlITORING b e by O Paul Kugrens 9 9 e e e
41 If1TRODUCTION This report consists of data collected from January through December 1978, and is made up of five tables that concisely illustrate the events observed during the latest monitoring period. Table I lists all of the species that were collected and identified at each site and the sample in which they were found. Additional tables that show monthly observa-tions for each site have been eliminated since it is not important to show the minor species in each collection and emphasis is placed on dominants. Table II indicates the dominant algal species for each site, the population counts, the frequency of each species in the population, and the general aquatic conditions that existed at the time of collection. Table III is new and gives the percent of diatoms, green algae, blue-green algae and euglenoids in each population and graphically presents these dominant groups and their fluctuations. Correlated with the percentages, Table IV presents species diversity data according to taxonomic divisions and Table V indicates the number of species identified at each site and categorizes them according to division. Collecting sites and techniques remained unchanged. Six sites were sampled - three on the South Platte River (SPI, SPGQ, SF), two on the St. Vrain River (SVI, SV) and Goosequill Pond (GQ). Periphyton and phytoplankton samples were taken at each site, however, only periphyton data are recorded from the river sites whereas phytoplankton data are listed for Goosequill Pond, since it was determined in the past that periphyton indicate "on site" conditions in rivers and phytoplankton are more indicative of standing water conditions. Only living organisms were included in the counts since dead cells, specifically of diatoms,
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.. 43 could alter the results and make insignificant the real differences between living cells. Diatom walls do not decompose because of the silica component and when materials are preserved it becomes impossible to determine which cells were living. Therefore my counts were conducted as soon after collec-tion as possible to assure accurate results and interpretations. OBSERVATIONS General patterns exhibited in previous years were observed during 1978 with some notable exceptions. A total of 157 species was collected and identified (Tables I and IV) in 1978 which is similar to the number identified last year. This number represents a low species diversity, and coupled with the algal species (listed above and in Table II) that dominate in the counts, indicates that the water is of low quality. These algae have a wide range of tolerance, therefore they are abundant throughout the year and are not severely affected by temperature changes, pollutants, or nutrient changes. Substrate shifts, currents and ice once again were the apparent major causes of population shifts and changes. Notable exceptions, however, occurred at SPI (where the dam water level was very low) and SP (where habitat for algae was altered by the effluent from Goosequill Pond) and are attributable indirectly to generating station activities. NitzsLiia palea was the dominant for most of the year in all river sites with only Navicula cryptocephala, Euglena viridis, and Stephanodiscus hantzschii being the other dominants. Ni_tzschia palea was the dominant. 81% of the time, Navicula cryptocephala 12%, and Euglena viridis and Stephanodiscus hantzschii 3% in the river sites. The dominance of ti. palea ranged from 26 to 945 of the populations with the more pronounced domination occurring from May through September. The percentages are based on 39 samples
44 containing living cells. Euglena again made its appearance during late winter and early spring creating large, green areas on moist mud and the S river bottom. Cladophora glimerata grew prolifically on rock and pebble substrates during late summer, and supported large, epiphytic growths of diatoms. O At site SPI, beginning in October, stagnant water conditions were created by the lowering of the dam and slow water flow. A considerable proportion of the population consisted of dead celis tnat had settled 9 forming a layer of debris 4-8 inches in depth, and creating anaerobic conditions. By November the living algal population had dropped precipi-tously (Table II). This drastic change should also have been noted in 6 the aquatic fauna, if living organisms are counted. Although only periphyton were counted a considerably large mat of quiet water algae, Enteromorpha, Spirogyra, Hydrodictyon and Lenna, covered the surface of G this stagnant water. The dominant in September, Stephanodiscus hantzschii, also indicated the lake-like conditions at site SPI. The second effect, although minor, occurs at FP. The effluent from O Goosequill Pond alters the algal composition by introducing Scenedesmus quadricauda. While chytoplankton contain considerable numbers of this species, periphyton had significant amounts of S;. quadricauda during 9 three months only. This, however, is a transient population since S.. quadricauda is not a river alga. Goosequill Pond experienced algal blooms similar to 1977. Scenedesmus 9 was the dominant during 10 months and the second dominant the other two months. Nitzschia palea and Cryptomonas ovata became dominant during February and April respectively. Consequently nothing unusual has 9 9
45 occurred in the flora of Goosequill Pond, although the effluent is being diverted through several ditches in which Scenedesmus remains the bloom alga, even in the winter. As evidenced through quantitative data in Table III, the river flora consists primarily of diatoms, whereas Goosequill Pond contains primarily green algae. Euglenoids make their appearance during late winter and early spring (February - April) with some sites increasing in euglenoids in December. Euglena viridis in puticular is a common alga of the winter flora and as such can be used as an indicator species during that time. Table IV shows the relativ^ similarity in species diversity at all river sites, with the exception of the St. Vrain River, which for some reason contains fewer species of green algae. Table V indicates the ratio of species from the four major groups of algae found in the vicinity of the Nuclear Generating Station and shows again the dominance of diatoms in the rivers. However, these data are misleading for GQ which shows the diatoms as being dominant but a comparison with Table III corrects the misrepresentation if only species diversities are used. Numerically, green algae are dominant. The trend to an increase in species diversity during the warmer months is also evident in Table V. In conclusion, nothing unusual has happened at most river sites that could be attributed to the St. Vrain Nuclear Generating Station with the exception of site SPI. Any anomaly, such as water retention behind a dam, however, corrects itself rapidly if proper conditions are restored.
46 Legend for Tables S SVI = St. Vrain Intake SV = St. Vrain below Intake GQ = Goosequill Pond 9 SPI = South Platte River below Intake SPGQ = South Platte River below Intake but above effluent SP = South Platte River below effluent near the confluence 4 Periphyton
'
A = B = Phytoplankton A I = Most abundant Periphyton for a given site and time , A2 = Second most abundant Periphyton When two or more identical superscripts occur, this indicates that those algae are present in equivalent numbers in the sample. , O 9 . 9 O O
'
47 Table I . Species List of Algae Found from January - December 1978. Genus or Species Sampling Sites SVI SV GQ SPI SPGQ SP Division Bacillariophyta Achnanthes exisna B B Achnanthes lanceolata AB AB AB AB AS AB Achnanthes minutissima AB A AB AB AB Amphipleura pellucida A Amphora ovalis A A A A AB Asterionella formosa AB AB AB B AB Biddulphia laevis AB AB A A AB Caloneis amphisbaena AB AB A AB AB A Cocconeis disculus A AB Cocconeis placentula AB AB AB AB AB Cyclotella meneghiniana AB AB A AB AB AB Cymatopleura solea AB A AB AB A Cymbella sp. A Cymbella lanceolata AB Cymbella minuta AB AB B B A Cymbella turgida B A A B AB B Diatoma elongatum B B AB AB Diatoma vulgare AB AB AB AB AB Entomoneis ornata A A A B Fragilaria sp. B A Fragilaria capucina B A Fragilaria construens AB A A AB AB A Fragilaria crotonensis AB AB AB A A Fragilaria vaucheriae B Gomphonema acuminatum AB A A Gomphonema constrictum A A Gomphonema lanceolata AB A A A AB Gomphonema olivaceum AB AB AB AB AB AB Gomphonema parvulum AB AB A AB AB AB Gyrosigma acuminatum AB A AB AB AB AB Gyrosigma obtusatum A Gyrosigma scalproides AB A Hannea arcus A A A Melosira granulata AB AB AB AB AB Melosira italica Melosira varians AB A A B AB AB Meridion circulare A Navicula sp. B Navicula capitata A Navicula cryptocephala AB AB AB AB AB AB Navicula cuspidata A AB AB AB A AB Navicula exigua A A A A AB
.
-
,
48 8 Ta bl e I . Species List of Algae Found from January - December 1978. (continued) 9 Genus or Species Sampling Sites SVI SV GQ SPI SPGQ SP N;<1cula minima AB AB A A AB B 4 Navicula pupula AB AB AB AB AB Navicula pygmaeg B A Navicula radiosa AB AB AB AB A Navicula rhynchocephala AB A AB AB A Navicula viridula AB AB B AB AB A Neidium iridis A A B B B 4 Nitzschia sp. AB AB A B Nitzschia acicularis AB AB B AB AB AB Nitzschia amphibia B Nitzschia apiculata A A Nitzschia dubia B B Nitzschia fonticola A A 9 Nitzschia gracilis A A A A Nitzschia holsatica AB AB B AB AB Nitzschia hungarica AB A8 AB AB AB AB Nitzschia ignorar.a A Nitzscnia linearis AB Nitzschia palea AB AB AB AB AB AB 4 Nitzschia sublinearis A A Nitzschia sigmoidea A AB AB A Nitzschia vermicularis A A A Pinnularia latevittata AB A A AB A AB Pleurosigma sp. A Rhoicosphenia curvata AB AB A AB AB AB 8 Rhopalodia gibba AB B Stephanodiscus hantzschii AB AB AB AB AB AB Surirella angustata A Surirella capronii A A A A A Surirella ovalis B B A Surirella ovata AB AB AB AB AB AB # Synedra rumpens A A Synedra ulna AB AB AB AB AB AB Division Chlorophyta Actinastrum hantzschii AB A AB A B # Ankistrodesmus falcatus AB AB AB AB AB AB Arthrodesmus convergens B Carteria olivieri> AB B B Chlamydomonas sp. AB B AB AB AB AB Chlorella sp. B Chlorococcum sp. B B B O Chlorogonium sp AB B AB B 9
49 Table I. Species Litt of Algae Found from January - December 1978. (continued) Genus or Species Sampling Sites SVI SV GQ SPI SPGQ SP Chlorogonium elongatum B Chlorogonium spirale AB Cladophora glomerata A A AB A Closteriopsis longissima AB A Closterium sp. A A A Closterium lunula A A A A A Coelastrum microporum B A AB B A A Cosmarium sp. AB A AB Crucigenia tetrapedia B Dictyosphaerium pulchellum AB A A AB Dysmorphococcus globosus B Enteromorpha intestinalis A A Gloeocystis gigas B B B B B Golenkinia radiata B AB B B A B Gonium pectarde AB Hyalotheca sp. Hydrodictyon reticulatum B A A Micractinium pusillum B B B B Oedogonium sp. A A A A Docystis lacustris B AB AB B Pediastrum biradians B Pediastrum duplex A A AB AB AB AB Pediastrum simplex A Pediastrum tetras 9 Pteromonas aculeata B AB B A B Rhizoclonium hieroglyphicum A A A A Scenedesmus acuminatus B A AB AB AB B Scenedesmus armatus AB B B B Scenedesmus bijuga B AB B Scenedesmus queJricauda AB AB AB AB AB AB Selenastrum sp. A B A B AB Spirogyra sp. AB A A A B Staurastrum sp. B B B Staurastrum chaetoceros A B AB AB Stigeoclonium tenue B AB B Ulothrix sp. A B B Voluox sp. A B Volvulina steinii A B Division Chrysophyta Anthophysa vegetans B Chrysameba sp. A B B B Dinobryon sp. A B AB Gonyostomum semen A A
50 9 Table I. Species List of Algae Found from January - December 1978. (continued) G Genus or Species Sampling Sites SVI SV GQ SPI SPGQ SP Division Cryptophyta 4 Chilomonas sp. B Cryptomonas ovata A B AB B B Divisinn Cyanophyta 4 Anabaena sp. AB AB AB AB AB Anabaena circinalis B B Anabaena flos-aquae AB AB AB AB AB AB Aphanizomenon flos-aquae D B B B AB AB Chroococcus dispersus C Dactylococcopsis S raphidioides AB AB AB AB AB AB Lyngbya sp. A AB Lyngbya iang A AB Merismopedia sp. B B Microcystis aeruginosa B B Oscillato ia sp. AB AB A A 9 Oscillatoria acuminata A A A Oscillatoria limosa AB AB AB A AB A Oscillatoria minnesotensis B B B B B Oscillatoria princeps AB AB A AB A AB Oscillatoria prolifica A A A A Phormidium sp. A A S Rivularia sp. A Spirulina major A A Division Euglenophyta Astasia sp. A 9 Euglena sp. A Euglena acus A AB AB AB AB AB Euglena viridis AB AB AB AB AB AB Phacus brevicanda B Phacus longicanda A Trachelomonas hispida B A # Division Pyrrophyta Gymnodinium sp. B Unident. dinoflagellate AB O Division Rhodophyta Audouinella violacea A e
51 Ta bl e I . Species List of Algae Found from January - December 1978. (continued) Genus or Species Sampling Sites SVI SV GQ SPI SPGQ SP Division Xanthophyta Tribonema aequale A Vaucheria sp. A A e O 4 0
Table II. Comparison of Algal Populations and their Dominarts as Influenced by Certain Physical Conditions at their Respective Sites. Results in Total Population, Dominant Species and Percent of each Species in the Population in parentheses. River Populations Represent Periphyton whereas GQ Represents Phytoplankton hunts. Months Site January February March SVI 241,872 82,351 885,067 Navicula cryptocephala (48) Nitzschia palea (39) Nitzschia palea (33) Nitzschia palea (32) Navicula cryptocephala (18) Euglena viridis (27) Surirella ovata (5) Stephanodiscus hantzschii (11) Navicula cryptocephala (20) Unidentified diatons (16) Stephanodiscus hantzschii (5) Unidentified diatoms (5) SV 60,503 329,405 1,238,632 Navicula cryptocephala (41) Nitzschia palea (36) Nitzschia palea (37) Surirella ovata (19) Navicula cryptocepha a (32) Navicula cryptocephala (23) m
"
Synedra ulna (11) Unidentified diatoms (18) Englena viridis (19) Nitzschia palea (6) Stephanodiscus hantzschii (5) Unidentified diatoms (9) GQ 10,293 4,239 77,099 Scenedesmus quadricauda (67) Nitzschia palea (40) Scenedesmus quadricauda (48) Nitzschia palea (16) Scenedesmus quadricauda (19) Eujlena viridis (31) Stephanodiscus hantzschii (14) Navicula cryptocephala (11) Nitzschia palea (11) Stephanodiscus hantzschii (7) Chlamydomonas sp. (5) SPI 181,509 235,421 792,002 Nitzschia palea (39) Euglena viridis (57) Nitzschia palea (55) Navicula cryptocephala (14) Nitzschia palea (20) Navicula cryptocephala (21) Stephanodiscus hantzschii (8) Euglena acus (7) Euglena viridis (15) Unidentified diatoms (14) Unidentified diatoms (6) Stephanodiscus hantzschii (5) 9 9 8 9 9 9 9 8 9 9 9
9 Table II. (continued) Months Site January February March SPGQ 365,119 44,117 439,067 Nitzschia palea (39) Nitzschia palea (50) Euglena viridis (52) Navicula cryptocephala (23) Euglena viridis (21) Nitzschia palea (16) Unidentified diatoms (11) Navicula cryptocephala (7) Navicula cryptocephala (11) Nitzschia hungarica (6) Euglena acus (5) Unidentified diatoms (11) SP 82,036 22,268 281,927 Nitzschia palea (44) Nitzschia palea (32) Nitzschia palea (26) Navicula cryptocephala (21) Navicula cryptocephala (19) Euglena viridis (22) Gomphonema parvulum (11) Euglena viridis (8) Euglena acus (17) Synedra ulna (6) Havicula cryptocephala (12) Unidentified diatoms (19) , w U General GQ - 2g C, Completely frozen GQ - 3g C, Part frozen GQ - 15.5U C; No ice, green water; Water SV - I C, g Ice along edges SV - 4 C, Ice along edges, flgwingwater Conditions SP - 2 C, Swif t, clear cfearwater SV - 17 C; Low, clear SP - 6 C High, swift SP - High, clear, swift Comments No visible algal populations. No visible algal populations. Euglena patches evident. Mostly dead cells present. Mainly dead cells in river.
Table II. (continued) Months Site April May June SVI 1,280,227 661,752 216,382 Nitzschia palea (39) Nitzschia palea (54) Navicula cryptocephala (29) Navicula cryptocephala (19) Navicula cryptocephala (22) Nitzschia palea (28) Euglena viridis (14) Nitzschia acicularis (6) Synedra ulna (8) Navicula minima (10) Gyrosigma acuminatum (6) Euglena acus (9) SV 485,285 14,075 42,016 Nitzschia palea (54) Nitzschia palea (66) Nitzschia palea (75) Navicula cryptocephala (20) flavicula cryptocephala (9) Navicula cryptocephala (15) Euglena acus (11) Euglena viridis (10)
$
GQ 40,125 99,578 230,668 Cryptomonas ovata (41) Scenedesmus quadricauda (73) Scenedesmus quadricauda (98) Scenedesmus quadricauda (22) Cryptomonas ovata (7) Euglena viridis (14) Chlorogonium sp. (4) Chilomonas sp. (6) Nitzschia palea (3) Nitzschia palea (4) SPI 1,081,492 3,030,404 1,848,704 Nitzschia palea (78) Nitzschia palea (92) Nitzschia palea (94) Navicula cryptocephala (12) Navicula cryptocephala (2) Navicula cryptocephala (3) Nitzschia acicularis (3) Nitzschia acicularis (2) SPGQ l,323,504 3,960,008 2,397,012 Nitzschia palea (62) Nitzschia palea (92) Nitzschia palea (93) Navicula cryptocephala (13) Nitzschia acicularis (4) Navicula cryptocephala (3) Gomphonema parvulum (6) 8 9 8 G S S e e e e e
9 6 O Table II. (continued) Months Site April May June SP 374,362 4,075,552 2,745,746 Nitzschia palea (74) Nitzschia palea (92) Nitzschia palea (86) Navicula cryptocephala (11) Nitzschia acicularis (4) Scenedesmus quadricauda (5) Navicula cryptocephala (3) Navicula cryptocephala (3) 0 General GQ - 11 C; High, water GQ - 22 C GQ - 28 C; High, green Water engeringandexiting SV - 14 C; Very high, swift entering and exiting Conditions SV - 16 C; High, swift turgid SV - 18 g; Very high, swift, turbid turbid SP - 17 C (21 C-SPI); Extremely SP - 28 C; Extremely low, clear SP - 16 C; High, swift, turbid low, clear E Comments Considerable Euglena and Large populations of diatoms. No populations evident in SV. and Diatom growth. Diatoms visible in SP.
Table II. (continued) Months Site July August September SVI 752,086 1,473,501 1,376,444 Nitzschia palea (49) Nitzschia palea (55) Nitzschia palea (56) Navicula cryptocephala (31) Nitzschia acicularis (16) Navicula cryptocephala (23) Navicula pupula (9) Navicula cryptocephala (10) Navicula pupula (5) SV 1,478,963 1,164,684 1,764,672 Nitzschia palea (59) Nitzschia palea (48) Nitzschia palea (41) Stephanodiscus hantzschii (17) Nitzschia acicularis (30) Navicula cryptocephala (31) Navicula cryptocephala (11) Navicula cryptocephala (14) Nitzschia acicularis (6) Navicula pupula (7) Navicula radiosa (5)
$
GQ 101,679 155,459 244,113 Scer.edesmus quadricauda (89) Scenedesmus quadricauda (88) Scenedesmus quadricauda (97) Anabaena flos-aquae (44) Golenkinia radiata (6) SPI 403,354 1,658,792 2,744,065 Navicula cryptocephala (51) Nitzschia palea (67) Nitzschia palea (55) Nitzschia palea (32) Stephanodiscus hantzschii (15) Stephanodiscus hantzschii (10) Navicula pupula (13) Navicula cryptocephala (5) Achnanthes lanceolata (8) Achnanthes lanceolata (5) G 9 9 9 9 9 6 4 8 9 9
Table II. (continued) Months Site July August September SPGQ 7,650,285 915,104 2,028,953 Stephanodiscus hantzschii (46) Nitzschia palea (60) Nitzschia palea (63) Nitzschia palea (28) Stephanodiscus hantzschii (11) Stephanodiscus hantzschii (18) Navicula cryptocephala (5) Navicula cryptocephala (10) Achnanthes lanceolata (5) Navicula pupula (7) Navicula cryptocephala (4) SP 2,376,J05 545,368 2,310,880 Nitzschia palea (54) Nitzschia palea (55) Nitzschia palea (53) Stephanodiscus hantzschii (18) Stephanodiscus hantzschii (15) Stephanodiscus hantzschii (22) Navicula pupula (7) Navicula cryptocephala (7) Navicula cryptocephala (7) Scenedesmus quadricauda (6) Scenedesmus quadricauda (5)
$
General GQ - 24 C; High, water exiting GQ - 28 C; High, green; water GQ - 16 C; Green, large effluent. Water angentering exftinginlargeamounts Conditions SV - 20 C; glower, turbid water SV - 21 g C, Low, clear SV - 26 C;gHigh, turbid SP 24 C; High, clear, some SP - 24 C; Low, clear water SP 28 C; Very low, clear swift currents, narrow channels o f water Comments Diatom patches evident. Large growths of Cladophora in large growths of Cladophora in GQ - green water. SP. Diatoms at all sites. SP. Large diatom populations evident.
.
Table II. (continued) Months Site October flovember December SVI 3,149,940 240,332 1,155 Nitzschia palea (47) Navicula cryptocephala (48) Nitzschia palea (100) Navicula cryptocephala (25) Nitzschia palea (35) Stephanodiscus hantzschii (12) Synedra ulna (8) Nitzschia acicularis (7)
-V 4,023,452 97,057 No living cells observed Navicula cryptocephala (64) Navicula cryptocephala (48)
Nitzschia palea (14) Nitzschia palea (31) Stephanodiscus hantzschii (13) IE GQ 68,904 40,335 39,075 ceredesmus quadricauda (93) Scenedesmus quadricauda (55) Scenedesmus quadricauda (56) Stept..nodiscus hantzschii (5) Stephanodiscus hantzschii (41 ) Chlamydomonas sp. (16) Stephanodiscus hantzschii (16) Euglena viridis (11) SPI 467,638 11,554 4,621 Stephanodis ;ontzschii (40) Nitzschia palea (60) Nitzschia palea (75) Nitzschia pas:e (3T Navicula cryptocephala (40) Navicula cryptocephala (25) 9 9 e # 9 e .9 e e S 9
3 9 4 4 S S S S 9 9 9 Table II. (continued) Months Site October flovember Decembor SPGQ 1,229,388 1,224,766 1,548 Nitzschia palea (59) Nitzschia palea (79) Nitzschia paiv (50) Stephanodiscus hantzschii (14 ) flitzschia hungarica (7) Stephanodiscus MnMschii (50) flavicula cryptocephala (12) Achnanthes lanceolata (6) Achnanthes lanceolata (5) Navicula cryptocephala (5) SP 1,428,124 818,051 13,865 Nitzschia palea (42) flitzschia palea (75) Nitzschia palea (50) Navicula cryptocephala (21) Navicula cryptocephala (19) Scenedesmus quadricauda (2s. Stephanodiscus hantzschii (16) flitzschia hungarica (25)
$
U General GQ - 14 C; Lower water, deep GQ - S C; High, light green, GQ - 1.5 C; 50% ice-covered, green and exiting soge ice warm ( C) keeping part thgough pipe SV - 50 C; Slow, turbid (SVI); ogen. Green water. SV - 15 C; glower, clear water sgift, turbid (SV) SV - 1 C; Ice along banks to SP 16 C; High, clear, swi f t SP - 7 C; High, clear, swi ft comgletely frozen SP 5 C; High, turbid, swift, no ice. Comments SPI - Lake-like conditions with Lake-like condi tions at SVI, No visible diatom populations in debris on bottom. SPI. Diatom populations rivers. visible in SPGQ, SP.
60 g Ta bl e III . Percent of Populations Comprised of Diatoms, Green Algae, Blue-Green Algae, and Euglenoids Sites Month SVI SV GQ SPI SPGQ SP January 100-0-0-+ 100-0-0-0 31-69-0-0 99-0-0-+ 100-0-0-0 100-0-0-0 February 100-0-0-0 100-0-0-0 45-42-0-6 36-0-+-64 76-1-0-23 91 0-8 G March 72-0-0-27 80-0-0-20 14-54-0-31 84-0-0-16 43-0-0-57 61 0-39 April 75-+-1-22 78-0-0-22 10-28-0-15 97-0-0-3 99-+-0-0 98-2-0-0 May 100-0-0-0 96-4-+-0 5- 92 +- + 99-1-0-0 99-0-1-0 99-0-0-1 June 100-0-0-0 95-0-5-0 1-98-1-0 100-0-0-0 10 0- + 0 95-5-0-0 July 99-0-l-0 99-1-0-0 1- 93 0 100-0-0-0 97-2-1-0 95-5-+-+ August 99-+-+-0 100-0-0-0 2-95-3-0 100-0-0-0 100-0-0-0 94-6-0-0 $ September 100-0-0-0 100-0-0-0 2 +-0 100-0-0-0 99-0-1-0 94-6-0-0 October 100-0-0-0 99-1-0-0 6-94-0-0 100-0-0-0 99-1-0-0 98-2-0-0 November 96-2-0-2 99-1-0-0 43-55-0-2 100-0-0-0 97-0-0-3 100-0-0-0 December 97-0-0-3 103-0-0-6 17-60-0-12 100-0-0-0 100-0-0-0 75-25-0-0 (+) indicates present in counts but below 1% and not significant. The~ percentages 9 are rounded off. Table IV. Species Diversity According to Taxonomic Divisions from January - December 1978 Sites Total species Division identified SVI SV GQ SPI SPGQ SP per division G Bacillariophyta 56 55 29 52 46 50 75 Chlorophyta 15 20 31 28 30 29 46 Chrysophyta 3 2 0 3 2 1 4 Cryptophyta 1 1 2 1 1 0 2 p Cyanophyta 13 12 12 12 8 10 19 Euglenophyta 2 5 4 2 3 2 7 Pyrrophyta 0 0 2 0 0 0 2 Rhodophyta 0 0 2 0 0 0 1 Xanthophyta 0 2 0 0 1 0 2 G Total number of 90 97 80 98 92 92 157 species per site 9 e
O 61 Table V. Diatom - Blue-green-Euglenoid Algal Species Ratios at Sampling Sites from January - December 1978 O Months Sites January February Ma rc h April flay June O SVI 22-1-0-1 21-2-0-2 19-2-0-2 26-3-4-2 27-2-1-0 32-2-4-0 SV 17-2-0-1 21-3-2-2 20-4-1-2 15-2-2-2 26-5-2-1 18-1-3-1 GQ 7-6-0-2 18-1-0-3 12-7-1-1 8-7-2-2 11-19-4-3 7-9-4-0 0 SPI 23-2-1-2 14-1-1-2 13-3-0-2 25-4-3-2 18-8-3-1 22-7-3-1 SPGQ 21-4-0-1 12-3-0-2 15-5-0-2 19-7-1-1 19-9-4-3 21 5-2 SP 17-1-0-1 13-2-0-1 13-2-0-2 20-12-1-2 15-4-4-1 25-10-3-0 0 Total n mber 35-10-1-2 35-9-2-3 33-11-2-2 41 -1 6-7-3 36-20-7-4 44-16-7-3 July fJgust September October riovember oecember O SVI 27-5-3-1 13-2-4-1 21 9-1 21 1-0 19-2-1-1 17-1-0-1 SV 21-5-3-2 18-5-2-2 23-8-5-1 19-3-4-0 14-1-2-1 15-0-0-0 GQ 2-12-5-0 3-7-4-0 4-7-3-0 9-7-4-0 4-8-3-2 10-6-1-1 O SPI 25-10-5-0 19-10-5-0 20-9-4-0 15-10-1-1 16-2-0-1 12-0-0-1 SPGQ 23-16-5-2 19-7-1-0 20-8-4-1 20-9 ^ l 14-0-0-1 13-2-0-1 SP 25-12-4-1 14-6-2-0 18-11-5-1 22-7-1-1 9-1-0-1 12-3-0-2 O Total number 41-25-7-2 34-17-10-3 37-22-14-1 36-18-10-1 28-10-4-2 28-8-1-2 O O O
O 62 O O O O O AVIAN SECTION O O O O O
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63 AVIAN MONITORING by Ronald A. Ryder 9
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65 9 INTRODUCTION This study is a continuing monitoring of the avifauna in a designate'd 8 area adjacent to the Fort St. Vrain Nuclear Generating Station near Platte-ville, Colorado. Data regarding populations of resident, migratory and breeding birds are available from April 1972 until the present. Avian O populations of 1978 are compared to those from past years of the study. DESCRIPTION OF STUDY AREAS Avian populations were monitored on 3 designated study areas as 8 described in previous annual reports and illustrated in Figure 1. Briefly, these are 1) the St. Vrain River study area, 71.6 ha (177 acres), located northwest of the Nuclear Station and bordered on the west and north by a the St. Vrain River, on the east by County Road No. 38, and on the south by pasture land; 2) the Goosequill Pond study area, 8.5 ha (21 acres), northeast of the reactor site, bordered on the south, east and north by e the South Platte River and on the west by agricultural land; and 3) the South Platte River study area, 52.2 ha (129 acres), immediately east of Goosequill Pond, bordered on the north, south and east by the South Platte e River and by agricultural land and Goosequill Pond on the west. CENSUSING PROCEDURES Each census began at sunrise on relatively clear and calm mornings, e Goosequill Pond was censused from the road encompassing its perimeter. The St. Vrain and South Platte River study areas were systematically searched by walking a loosely defined route through each area and identi- , fying every bird observed within the boundaries of the area. Identifica-tions were aided by use of 7- or 8-power binoculars. Birds seen were immediately recorded on standardized field forms. During the breeding , season " spot maps" were made of territories of breeding males. Addi-tionally, nesting birds around Goosequill Pond and in the slough on the 4
66 St. Vrain area were followed closely to determine nesting density and success. Reports dealing with breeding pairs were submitted, as in previous years, to American Birds. All 3 areas were censused 16 times each in 1977 and 1978. Earlier census numbers were over 20 per year. FIf1DIf1GS Graphs of seven-year population trends are included with this report (Figures 2 and 3). They are divided by seasons. Summer, fall and winter populations have fluctuated widely, and little trend is apparent. Spring populations, however, show a fairly distinct pattern of an overall decline in avifauna in 1973 followed by a steady recovery to 1977, with a slight decline in 1978. The sharp decline in 1973 can probably be attributed to habitat deterioration due to flooding. The recovery is probably attributable to a natural return i'o pre-flood conditions. Grazing of livestock was reduced in 1977 but increased somewhat in 1978. The spring migration in 1978 was delayed by unusually late snowfall, and the fall migration was somewhat earlier than normal. The non-breeding seasons for all seven years were marked by irregular fluctuations of populations, but breeding bird numbers are believed to be a more sensitive indicator of the state of the habitat. Results regarding breeding bird populations were reported in the January 1 - June 30,1978 progress report. Briefly, breeding birds were scarcer in 1978 than 1977. Yellow-headed blackbirds, particularly, had a very poor breeding season with low hatching success. Most other species fared better. See Tables 2 and 3. Weather in fall 1978 was more severe than in 1977 although comparatively little snow had fallen as of 1 December 1978. Environmental disi.uruances were again minimal, although greater than in 1977. Rather heavy grazing of the areas was seen in early spring and late summer. Levels of water in Goosequill Pond were kept fairly
67 9 constant by a regulating device. Irrigation in the adjacent fields caused pronounced fluctuations in the water levels of the beaver ponds throughout the summer. Fall levels in the beaver ponds were high. Efforts were made by the cattle-operator to poison prairie dogs. One mourning dove was found dead with suspected poisoned grain in its crop. Prairie dog numbers recovered by fall, so it is believed the prey base they provide for raptors such as great horned owls was not seriously al tered . O 9 9 9 9 9 9
lable 1. Seven-year tabulation of species numbers and population levels from monitoring at the Fort St. Vrain Nuclear Generating Station (number of species seen per count followed by total individuals). Time Period 1972 1973 1974 1975 1976 1977 1978 January No count 19(762) 19(319) 20(335) 10(340) No count No count February No count 19(2884) 24(15,474) No count 23(422) 24(478) 29(847) March No count 32(709) 25(14,063) 29(709) 33(627) 30(715) early April 28(823) 26(326) 32(487) 34(688) 38(720) No count 43(622) late April 50(871) 34(561) 37(441) 44(719) 46(903) 40(717) 1st wk May 47(574) j 33(381) 45(534) 45(591) 48(729) No count 2nd wk May 47(583) 39(382) 62(833) 52(533) 47(777) 50(640) 3rd wk May 48(593) 45(543) 43(563) 55(728) 54(855) 43(522) 45(466)1I $ 4th wk May 48(691) 38(450) 46(523) 50(635) 49(656) 45(565) 1st wk June 35(500) 39(373) 40(641) 42(491) 38(569) 49(614) 43(518) 2nd wk June 41(558) 33(414) 42(583) 40(419) 42(513) 46(660) 42(450) 3rd wk June 38(551) 38(426) 33(469) 34(340) 39(585) 44(635) 40(457) 4th wk June 37(509) 32(324) 34(426) 37(373) No count 40(539 41(510) 1st wk July 36(704) 33(421) 32(537) 32(483) 38(731) No count 40(560) 2nd wk July 37(681) 29(433) 34(541) 36(522) No count No count No count 3rd wk July 36(680) 34(437) 37(478) No count 41(600) 38(534) 29(409) 4th wk July 37(588) 30(779) 36(550) 40(1145) No count No count
Table 1, continued. Time Period 1972 1973 1974 1975 1976 1977 1978 1st wk August 37(658) 28(838) No count No count No count No count 38(750) 2nd wk August 38(851) 34(1123) 40(386) No count No count 34(571) 3rd wk August 42(757) 33(997) 35(565) 46(685) 37(2289) No count 36(377) 4th wk August No count No count No count No count No count No count 1st wk September 43(1080) 36(1287) 40(879) No count No count No count 38(897) 2nd wk September No count No couat No count 43(1917) No count No count 3rd wk September 45(605) 43(879) 47(2392) No count 37(1046) 41(980) 31(1008) 4th wk September No count 36(963) No count No count No count No count October 36(1190) 29(1402) 29(532) 31(442) 46(596) 34(856) 30(1692) $ November 32(1642) 23(455) 23(2057) 27(387) 33(580) 26(458) 26(565) December 23(611) 22(283) No count No count No count No count No count E May 1973 counts probably not comparable to those in 1972 and 1974. Due to floods, it was not possible to complete counts of all 3 areas weekly in May 1973. Early May count in 1978 delayed by unusually late snowstorm. e e e 4 4 9 9 9 9 6 9
70 Table 2. Summary of the 1978 intensive nest search on the St. Vrain Slough and Goosequill Pond, based on completed nests only. Total Percent Percent Percent Mean 2 Area and Species Nests SuccessfullI Unsuccessful Unknown Clutch Size / St. Vrain Slough Red-winged Blackbird 25 44.0 36.0 20.0 3.9(11) / Mourning Dove 8 50.0 33.33 17.67 2.0(4) Western Meadowlark 1 - - 100.0 - 9 Goosequill Pond Yellow-headed Blackbird 33 9.09 87.88 3.03 4.0(3)
- 1/Eggs to fledglings.
yj 77 Based on successful nests only.
-() = n or sample size; those nests where number of eggs found was known. .-
Table 3. Total nestings of Red-winged and Yellow-ho > 1 Blackbirds at the 9 Fort St. Vrain Nuclear Generating Station, 1972-1972 Number of Nests Followed l Species 1972 1973 I 1974 1975 1976 1977 1978
- Red-winged Blackbird 27 25 27 16 26 68 23 Yellow-headed Blackbird 54 20 31 56 53 100 33 g 1/ Goosequill Pond was drained in flay 1973.
9 9
71 O 1000-- 1977 = 1445 Summer G 900-- O 800__
'
4 Spring 700 --
/
\ .
7 600-- [
\ \
~.
\ /
-
500 --
/ *
\ /-
v ' l l l i l l 1972 1973 1974 1975 1976 1977 1978 9 Figure 2. Spring and summer mean numbers of individuals observed during seven-year period. (Spring = April, May and June. Summer = July and August.) O e e
72 1000 -- Fall 800 -- 600 --
/
/
400 -- /
!
200 --
/
/
e-
--
Winter f l 1972 1973 1974 19 5 1976 1977 1978 Figure 3. Fall and winter mean numbers of individuals observed during seven-year period. (Fall = September through December. Winter = January, February and March.) O
73 TERRESTRIAL SECTION O 9 9 9 O '
74 g VEGETATIOff MONITORING O O Charles D. Bonham Dot Helm O O O O O
75 INTRODUCTION Natural plant communities at the St. Vrain Nuclear Generating Station are being monitored for changes in species which may occur throughout the next 2 or 3 years if the station causes environmental changes. Such .
-
changes, it significant, can be interpreted with respect to natural or man-caused fluctuations as soon as enough infonnation exists about the individual plant species in these communities. Data on species characteristics of plant communities at the St. Vrain Nuclear Generating Station have been collected since 1972 and are useful for an adequate interpretation as to environmental effects on these communities. This year,1978, is the second year of a three-year monitoring effort for the native plant communi-ties. METHODS Field sampling was conducted in June and August,1978. This report contains results of August 25-27, 1978 collection period. Cover values for all major herbaceous plants and shrubs were estimated by 25 samples from each exclosure and an additional 25 samples were taken from an area adjacent to each exclosure. Standing crop values for aboveground biomass were obtained in August by clipping 15 quadrats inside the exclosure and 15 quadrats outside the exclosure. Species were clipped according to dominant species inside the exclosure. All other species were grouped under "Other species." Fresh weights for species were measured in the field and fresh material per category per exclosure was oven-dried to determine dry matter percentage for the categories. The vegetation in the St. Vrain River loop area formed
76 8 a mosaic of Lepidiun' latifolium and Cirsium spp. with patches of other vegetation interspersed. Approximately equal areas of both were present and were sampled as such. Cover data were analyzed across all years for each exclosure using a nested analysis of variance design where inside/outside exclosures were nested within season and seasons within years. Significance tests were perfonned at the 5-peccent level of confidence. O RESULTS The confluence exclosure (exclosure 1) had differences in production O inside and outside the exclosure for Agropyron trachycaulum and "Other species" (Table 1). The irrigated pasture exclosure (exclosure 2) had larger production values for Bromus inermis and Polygonum coccineum inside the exclosure while "Other species," particularly Festuca elatior, were larger on the outside (Table 2). Polygonum and Bromus dominated the inside of the exclosure to the extent that the Festuca was not considered a dom-O inant there this year. The Goosequill Pond exclosure (exclosure 3) had more Bromus tectorum production inside the exclosure (Table 3). The exclosure north of the station (exclosure 4) was dominated by Ambrosia 9 coronopofolia but the only significant standing crop differences between inside and outside were for "Other species" (Table 4). The exclosure south of Ben Houston's (exclosure 6) had rare Agropyron 9 elongatum standing crop and cover inside while there was more production for "Other species" outside (Table 5). Production for individual species in the South Platte River exclosure (exclosure 8) did not differ between 9 inside and outside (Table 6). Lepidium latifolium and Cirsium spp. dominated O
77 Table 1. Standing crop (dry weight, g/m ) for dominant plant species in the confluence exclosure (exclosure 1) compared to outside, August 25-27, 1978. __ _ In (n = 15) Out (n = 15) Category Dry _ Dry x s- Matter x s- Mafter P Other species 14.6 6.17 57 49.7 12.34 52 .02 Agropyron trachycaulum 32.0 13.3 58 3.8 2.75 50 .05 Bromus japonicus + B_. tectorum 16.8 6.43 84 8.8 3.25 80 .27 Symphoricarpos occi-dentalis 20.7 11.62 41 17.8 11.63 45 .86 Total vegetation 84.1 1 5.81 80.1 16.96 .86 Table 2. Standing crop (dry weight, g/m2 ) for dominant plant species in the irrigated pasture exclosure (exclosure 2) compared to outside, August 25-27, 1978. Other species 11.0 6.19 53 165.3 18.29 19 .00 Bromus inermis 103.1 24.22 24 0.0 0.00 .00 Polygonum coccineum 163.7 42.22 25 0.0 0.00 .00 Total vegetation 277.8 39.50 165.3 18.29 .02 Table 3. Standing crop (dry weight, g/m ) for dominant plant species in tne Goosequill Pond exclosure (exclosure 3) compared to outside, August 25-27, 1978. Other species 31.0 6.83 57 59.0 14.51 64 .09 Bromus tectorum 31.2 7.27 86 9.3 4.39 87 .02 Total vegetation 62.2 5.07 68.4 13.40 .67 4 0
78 9 Table 4. Standing crop (dry weight, g/m ) for dominant plant species in the exclosure north of the station (exclosure 4) compared O to outside, August 25-27, 1978. In (n = 15) Out (n = 15) Category Ma er x G i s- sg Ma r P Other species 28.4 8.39 50 71.6 19.38 73 .05 Ambrosia coronopofolia 44.0 10.83 31 21.0 4. l fi 29 .06 Total vegetation 72.4 11.04 92.6 17.6/ .34 , Table 5. Standing crop (dry weight, g/m ) for dominant plant species in the exclosure south of Ben Houston's (exclosure 6) compared to outside, August 25-27, 1978. O _ Other species 1.7 1.14 32 19.2 7.58 29 .03 Agropyron elongatum 348.3 79.87 45 24.3 10.04 35 .00 9 Distichlis stricta 161.2 38.80 56 205.5 18.64 54 .31 Total vegetation 511.2 69.86 48.9 20.95 .00 9 Table 6. Standing crop (dry weight, g/m2 ) for dominant plant species in the South platte River exclosure (exclosure 8) compared to outside, August 25-27, 1978. G Other species 65.9 19.46 58 62.0 11.91 51 .86 Rhus radicans 24.6 7.55 34 21.4 11.96 32 .83 Symphoricarpos occi-dentalis 61.7 20.19 47 21.0 9.80 45 .08 g Total vegetation 152.1 19.01 104.3 14.40 .05 9 9
79 the St. Vrain River loop (exclosure 5) (11ble 7). Panicum virgatum pro-duction was not significantly different between the two portions of the association in the loop but all other species except Lepidium and Cirsium were more productive in the other portion of the association. The confluence exclosure had larger cover values for Rosa nutkana inside the exclosure. Cover values for the irrigated pasture exclosure followed the same trend as the production values: Bromus inermis and Polygonum coccineum cover values were larger inside while Festuca elatior war larger on the outside. Both Brom y and Festuca had few seed heads and the leaves had been cufficiently eaten by insects to make identification d'. f fi cu l t . Echinochloa crusgallis occurred only outside the exclosure while Setaria lutescens was found only inside. Bromus inermis and Poa pratensis had larger cover values inside the Goosequill Pond e:: closure but Salsola kali, Sporobolus cryptandrus, and Phyla cuneifolia had more cover outside. The exclosure north of the station had larger cover values for Salsola kali outside the exclosure. Ambrosia coronopofolia cover increased from almost less than one percent last year to 19 percent cover inside and 16 percent cover outside this year. The exclosure south of Ben Houston's had larger values for cover of Distichlis stricta and Kochia scoparia outside the exclosure while Agropyror elongatum covered more area inside. Ambrosia coronopofolia had more cover outside the South Platte River exclosure while Rhus radicans had more cover inside. Cover differences betwNn the two portions of the association in the St. Vrain River loop ..cce found for the follo,ing species: Ambrosia coronopofolia, Cirsium spp., Distichlis stricta, and Lepidium latifolium. O
00 9 Table 7. Standing crop (dry weight, g/m ) for dominant plant species in the St. Vrain River loop (exclosure 5), August 25-27, 1978. 9 Lepidium-Cirsium (n=15) Other (n=15) Dry Dry x s Matter x s Matter P x ~ x Other species 5.9 3.08 32 61.7 23.79 32 .03 Cirsium spp. 116.3 18.17 27 0.0 0.00 .00 Distichlis stricta 10.6 10.63 69 81 .8 27.96 69 .02 Lepidium latifolium 111.4 20.82 50 0.0 0.00 .00 g Panicum virgatum 13.8 7.95 45 39.5 25.82 45 .35 Total vegetation 258.1 17.92 183.0 28.02 .03. O 9 9 9
,
9 9 9
81 The analysis of variance over years and seasons perfonned on cover data showed that the confluence exclosure had yearly differences in cover values for Cardaria draba, Kochia scoparia, and Symphoricarpos occidentalis. Seasonal variations were found for Agropyron smithii, Ambrosia coronopofolia Bromus inermis, and B. japonicus. B. tectorum and Cardaria draba had signif-icant cover differences between inside and outside the exclosure when all years were considered. Yearly differences in the irrigated pasture exclosure were found for Bronus inenuis while inside/outside differences were found for B. inermis, Dactylis glomerata, Festuca elatior, and Polygonum coccineum. Yea rly differences in the Goosequill Pond exclosure were det.ected for Ambrosia coronopofolia and Kochic scoparia. Seasonal differences occurred for Bromus tectorum and Taraxacum officinale. Inside/outside differences occurred for Ambrosia coronopofolia, Distichlis stricta, Poa pratensis, Salsola kali, and Sporobolus cryptandrus. No species with yearly differences were noted in the exclosure north 9 of the station but Ambrosia, B. tectorum, Salsola kali, and Sporobolus cryptandrus had both seasonal and inside/outside differences when data for all years was considered. Kochia had only seasonal differences 9 None of the species in the exclosure south of Ben Houston's showed seasonally or yearly trends, but Agropyron elongatum, A. smithii, D.
.
stricta, K. scoparia, and Poa pratensis showed differences with respect to
-.
inside and outside the exclosure when data were analyzed across all years. The South Platte River exclosure had yearly differences for A. smithii, _ Panicum virgatum, and Poa pratensis. Seasonal changes occurred for B. inennis and Taraxacum officinale while differences with respect to the exclosure were O
82 e noted for A. coronopofolia, B_. inermis, and Rhus radicans. No yearly differences were observed for species in the St. Vrain River loop, but 8 Agropyron smithii, Ambrosia coronopofolia, B_. inermis, Cirsium spp. , D. _ ' ricta, Poa pratensis, Sporobolus cryptandrus, and Taraxacum officinale had seasonal differences when the data from all years were analyzed. # DISCUSSION Some variations in species between 1977 and 1978 might have resulted O from different climatic conditions in the two years. The year 1977 was very dry while the winter and spring of 1978 were very wet. A major snowstorm occurred on May 5 and 6. The surrmer, however, was relatively dry. O These weather differences resulted in different phenological dates for various stages in 1978 relative to 1977. Both June and August sample periods were later this year to compensate for this effect. Insects also 8 appeared to have removed some vegetation in exclosures. Two annual grasses were encountered in 1978 in the irrigated pasture exclosure for the first time and were probably a response to the weather.
- Setaria lutescens was found only within the exclosure while Echinochloa crusgalli was only on the outside. Polygonum coccineum had increased since 1977 but had been heavily grazed by insects. The area outside the exclosure I was not being grazed by livestock at the time of sample whereas in 1977 the pasture was grazed.
This year, 1978, was the first that the St. Vrain River loop had been 8 stratified for sampling. The Lepidium-Cirsium overstory has probably supressed growth of lower vegetation so this stratum was a relatively The rest of the mosaic was relatively complex with a O species-poor area. 9
83 patchwork of several small communities. Panicum virgatum was present in both parts of the associatio;. and accounted for more cover in 1978 than in 1977. Its presence under the Lepidium-Cirsium overstory was surprising since almost nothing was observed there last year. Insect removal of the overstory leaves provideo a more open canopy in 1978 so that light could enter. Whether the Panicum was responding to increased light this year or whether it was stunted and unobservable under the canopy last year is not known. Most /egetation differences that occurred in 1978 relative to 1977 probably resulted from different weather conditions, insect herbivory and phenological stage at the time of sampling. No observed changes could be attributed to the operation of the St. Vrain Nuclear Generating Station. Yearly variations since 1973 have been reported only for Cardaria draba and 9 Symphoricarpos occidentalis in the confluence exclosure, B. inermis in the irrigated pasture, hnbrosia coronopofolia and Kochia scoparia in the Goose-quill exclosure, and Agropyron smithii, Panicum virgatum, and Poa pratensis e in the South Platte River exclosure. 9 9 9 O
9 84 0 0 4 IRRIGATED PASTURE M0filTORIf;G O O Charles D. Bonham Dot Helm Robert Carmichael 9 9 9 9 0
85 It4TRODUCTI0?1 Since vegetation is an environmental indicator, it may reflect either stressed or improved conditions which result from increased water temperatures, chemical additives, or algae in the blowdown water used for irrigation of a seeded pasture mated north of the St. Vrain fluclear Generating Station. The Goosequill Ditch carries water used in the cooling process to this pasture for irrigation. Hence, vegetation pro duction in the pasture may be affected by greater thennal values of irrigation water used, the object of this investigation. flalco 345, a phosphated ethoxylated glycerine, is added to the cooi as water at the station to inhibit corrosion (U.S. Atomic Energy Commiss 1972). Several other compounds are added to the water to contro'. d, reduce algae formation, and prevent foaming (U.S. Atomic :r,m 3y Commission 1972). Algae have also been reported in the blowdow.
- c. used for irrigation and not in the other irrigation wate: ;<n ' for other pastures (Kugrens 1977). Since irrigation water is vu applied equally across the pasture (Bonham and Helm 1978), these ch% cal additives and algae could also affect the vegetation producti a In addition, water chemical levels 9 probably affect the soil chemia; 'evels.
Vegetation is affec'.c w all the above factors, but the purpose of this study is to isc!'u .ie thennal effects of the irrigation water. 9 Standing crop in ec~ exclosure, soil chemical levels, water chimiical levels, and u vr temperatures are being monitored in each observation period. Thw exclosures were constructed in early 1977 for protection 9 from ornin and other disturbance. Separate adjustments of the standing creo _ made for soil chemicals and for irrigation water temperatures O
86 8
.ing covariance analysis to detemime if production among exclosures is 9
affected by water temperature. METHODS 9 Irrigation Water Temperature Irrigation water temperatures were measured every hour for 24 hours with an electronic temperature probe af ter the start of irrigation at 7 a.m. September 2,1978, and continued until 7 a.m. September 3. The water had not reached the third exclosure by the end of this period. Two more readings were obtained at 2 p.m. and 3 p.m. on September 3, but still no water was in the last exclosure. A series of temperatures were obtained every half hour for all three exclosures beginning at 5 a.m. on September 4 and lasting for three hours until the gates were closed. This September period was the only time that the investigator received sufficient notice of irrigation water release into the pasture. This problem has now been resolved for future observations. Vegetation Sampling No grazing by livestock was permitted in the exclosures during 1977 which permitted a buildup of litter and standing-dead vegetation. Vegetation in the exclosures was mowed and all material was removed during July, 1978, so that vegetation growth would not be hindered by the litter. Clipping was conductes September 12, 1978, eight days after comple-tion of irrigation to determine vegetation production. Samples were obtained inside the protected area for the two exclosures nearest the Goosequill Ditch but outside the exclosure for the third one. The exclosures t were numbered with increasing distance from the ditch. The samples for the
,
4
87 third exclosure were caken from an area that appeared ungrazed. This latter effort was an attempt to minimize effects of the litter buildup which had apparently killed more individuals in the third exclosurc since it had the most litter. Standing-live vegetation was clipped in 20 quadrats, 20 x 50-cm, for each exclosure. :n c,.a Arats were clipped in each half of each exclo-sure so that two replicates of 10 observations at each distance were obtained. Quadrats were located randomly with the long axis perpendicular to the irrigation ditch. Each half of each exclosure was set up as a 10 x 10 grid with a margin along the edges. Random location coordinates were selected for each replicate. Clipped material from eEch replicate was oven-dried at 105 C for 24 hours to obtain a dry weight adjustment factor. Statistical analyses were performed on oven-dried values. Irrigation Water Chemicals Three irrigation water samples were obtained in the Goosequill Ditch near its exit to the exclosures at the end of irrigation on September 4, 1978. These were analyzed for the following characteristics: pH, electrical conductivity, sodium absorption ratio (SAR), Ca, Mg, Na, K, P, NH , and NO ' 4 3 Soil Chemicals Seven random soil cores, 1.9-cm inside diameter, were obtained with a soil core tube to a depth of 20 cm in each quarter of each exclosure on September 16, 1978. and combined so that each exclosure was represented by four composite samples. The soils were collected four days after the vegetation samples because of moisture conditions. Each composite sample was analyzed for pH, electrical conductivity, total N, organic matter,
.
O
88 e moisture content, and the following plant available nutrients: Ca, Mg, Na, K, P, NH , NO , Fe. nd Zn. Ca, Mg, and Na had been analyzed for water
- 4 3 soluble levels in 1977 but were changed to plant available levels in 1978 for reasons discussed in the June,1978 report (Bonham and Helm 1978).
Samples for June,1978 were also analyzed for percent sand, silt, and clay.
- Soil data were analyzed statistically with a nested analysis of variance, fixed effects model for replicates and a random effects model for exclosures. Significance tests were performed at the 5-percent level and
- Turkey's test was used as a mean separation tests.
RESULTS g Irrigation water temperatures (Table 1) ranged from 24.4 C to 32.5 C in the ditch at 7 a.m. and 4 p.m., respectively. The range of temperature O in the first exclosure was from 25.0 C to 32.5 C which occurred at the same time as those in the ditch. The second exclosure had a water temperature range of 22.2 C to 33.1 C which occurred at 3 a.m. and 9 a.m. , respectively. The secondexclosure did not receive water until 5 p.m. Means and standard errors for vegetation production were calculated and exclosures did not have different production levels at the 5-percent significance level. Chemical analyses for the irrigation water in June and September were conducted. P levels were higher in June than in September while Mg was higher in September than in June. The P levels might be attributable to phosphated chemicals added to the cooling tower water to inhibit corrosior,. t0 -N also fluctuated between nmple periods. 3 O 9
89 Table 1. Irrigation water temperatures for September 2,1978 ( C). Means were calculated only for observations when water was present. A dash (-) indicates that water was not present. Ditch Exclosure 1 Exclosure 2 Exclosure 3 Time Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 3 7 a.m. 24.4 - - - - - - 8 a.m. 26.1 25.0 25.0 31.9 - - - 9 a.m. 26.9 26.1 26.1 33.1 - - - 10 a.m. 27.8 27.5 27.5 - - - - 11 a.m. 28.6 28.3 28.3 - - - - 12 noon 30.6 30.8 30.8 - - - - 1 p.m. 31.1 30.8 20.8 - - - - 2 p.m. 31.7 30.8 30.8 - - - - 3 p.m. 31.7 31.9 31.4 - - - - 4 p.m. 32.5 31.7 32.5 - - - - 5 p.m. 31.9 31.7 31.7 30.8 - - - 6 p.m. 31.1 30.8 30.8 29.4 28.9 - - 7 p.m. 30.3 29.7 30.0 27.8 26.7 - - 8 p.m. 30.0 29.4 29.4 26.7 25.6 - - 9 p.m. 29.7 29.2 29.2 25.0 23.3 - - 10 p.m. 29.4 29.2 28.9 24.4 22.8 - - 11 p.m. 29.4 28.9 28.9 24.4 22.2 - - 12 p.m. 28.9 28.3 28.3 23.9 21.7 - - 1 a.m. 28.1 27.5 27.5 23.3 21.1 - - 2 a.m. 27.8 27.2 27.2 22.5 20.3 - - 3 a.m. 27.5 26.7 26.7 22.2 20.0 - - 4 a.m. 27.5 26.7 26.7 22.2 20.0 - - 5 a.m. 27.5 26.7 26.7 22.2 20.0 - - 6 a.m. 27.5 26.7 26.7 22.2 20.0 - - 7 a.m. 27.5 26.7 26.7 22.2 20.0 - - x 29.0 28.7 28.7 25.5 22.3 - - s-x 0.41 0.41 0.42 0.90 0.77 - -
90 0 Most soil chemicals differed across the pasture in 1978. Some of these soil chemical differences might be inherent in the soil but others, ' particularly the P, might be induced by chemicals in the irrigation treat-ment. Some differences, such as Ca, ha e shown the same trends in each sample period. The chemicals in the irrigation wat'r would have unequal
- effect because the irrigation wat r levels were highr',t in the exclosure nearest the Goosequill Ditch and the third exclosure had much less water, if any. O The pH was highest in the first exclosure which could be a result of the irrigation water since its pH varied between 7.5 and 7.9. Plant available Ca levels were highest in the first exclosure and lowest in
- the second in both periods. Plant available Mg levels were largest in the third exclosure in June, but there were no significant differences in September. The last Mg data had an outlier observation without which
- similar trends might have been observed. Plant available Na levels were largest in the third exclosure and lowest in the second. The P level was much larger in the first exclosure, but the other two exclosures did
- not differ from each other. September P data were higher than June data for soils but the reverse was true for water. NH had its largest values 4
in exclosure 2 and smallest in exclosure 3 in Ju n but no differences were
- obtained in September. NO3
-N were highest in the first exclosure in both sample periods and were higher in June than in September. Water NO 3-N was O
also higher in June. Fe showed decreasing levels with distance from the ditch. Zn had its smallest values in exclosure 2 while exclosures 1 and 3 were not different. Similarly, total N was lowest in the second exclosure. O O
91 Organic matter differences occurred only in September, but no differences were detected with a mean separation test. The following soil nutrients were applied in 1977: 150 lb/ acre total N,10 lb/ acre S (504), 5 lb/ acre Zn, 3 lb/ acre Mn, and 0.5 lb/ acre B (Keith Russell, personal communication). NO fertilizer has been applied each 3 year but not within the exclosure. Monitoring of all these soil chemicals should continue since there were differences across the field. Thermal effects on production can be evaluated only if the biomass is first adjusted for effects of these soil nutrient levels. Additionally, chemicals added to the blowdown water might be affecting the soil levels. Algae in the irrigation water reported by Kugrens (1977) has not been monitored in our study. What was believed to be these algae were observed and collected from the bare areas between plants in exclosure 1 on September 16 while sampling soils. This occurrence of algae will be taken into consideration for future monitoring. LITERATURE CITED Bonham, Charles D. , and Dot Helm. 1978. Irrigated pasture monitoring. In Ecological Monitoring Fort St. Vrain Generating Station, Progress
-
Peport January 1,1978 - June 30,1978. pp. 98-107. Kugrens, Paul , 1977. Algal monitoring. I_n Ecological Monitoring Fort St. Vrain Generating Station, Progress Report July 1,1977 - December 3, 1977. pp. 29-33.
92
'
_C0 PHYSIOLOGICAL CHARACTE'!ISTICS OF VEGETATION SURROUNDING THE ST. VRAlt' ' UCLEAR GENERATING STATION a by M. J. Trlica R. S. Carmichael Dot Helm O O
.
O O
93 INTRODUCTI0f1 Terrestrial vegetation surrounding the St. Vrain Nuclear Generating Station may be directly or indirectly affected by the plant's operation. Operation of the power plant will probably result in releases of small amounts of radionuclides. Heat, water vapor and salts will also be lost to the atmosphere as a result of cooling tower operation. In addition, water effluents will be released from the station which could affect vegetation along the water courses or in irrigated pastures. It is, therefore, desirable to have an inventory of the ecophysiology of the vegetation which might be affected by increased heat, water vapor, and salt deposition as a result of cooling tower operations. Since all animal life is dependent either directly or indirectly upon vegetation as a source of food, decreased productivity or palatability of vegetation may be detrimental to animal populations. In addition, operation of the cooling towers may result in increased humidities and temperature changes in the immediate surrounding environment. Since the St. Vrain Nuclear Generating Station is in the Denver Air Pollution Corridor, increased humidity could interact with vegetation, resulting in increased leaf injury caused by the pollutants. Numerous studies have indicated that a signifi-cantly-detrimental interaction exists between air pollutants and humidity which can cause severe damage to phytosynthetically-active tissues. OBJECTIVES The objectives of this study were:
- 1. To determine leaf damage by pollutants, disease, and insects
) for certai . . species surrounding the generating station.
94 e
- 2. To determine concentrations of important elements in foliage of several species as related to distance and direction from 0 the generating station.
METHODS O Leaves of cheatgrass (Bromus tectorum), kochia (Kochia scoparia), and cottonwood (Populus sargentii) were collected from a maximum of 32 locations on four radii at distances of 1/S,1/4,1/2 and 1 mile from the , generating station during rapid spring growth from 1972 through 1978 (Figure 1). Sampling of kochia and cottonwood at these same locations was again repeated when vegetation was mature in August,1972 through 1978. , Estimates were made for each leaf sampled for total leaf area, leaf area injured by chewing insects, and leaf area spotted caused by air pr!1utants, disease, nutrition, and sucking insects. , Chemical analyses were conducted on foliage samples of cottonwood, kochia, and pinto beans (Phaseolus vulgaris). These analyses indicated if concentrations of various nutritive and toxic elements were influenced by , either distance or direction from the generating station. The chemical analyses were not completea by the time of report writing and will, there-fore, be reported upon in the July, 1979 report. , A literature search indicated that pinto bean plants are sensitive to air pollutants. As pinto beans are an important crop produced in the area around the St. Vrain Nuclear Generating Station, they were utilized , in 1973,1974,1976,1977, and 1978 as a controlled experiment to detennine effects of air pollution and drift at varying distances and directions from the cooling towers. g G
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96
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Pinto beans were planted in polyethylene-lined #10 cans in the green-house. All plants received similar treatment in the greenhouse until mid- # July, when plants and containers were transported to the St. Vrain study site. Sixty-four containers with bean plants (four container / location) were placed at two distances and eight directions from the cooling towers. O Distances from the towers were 50 feet and 1/4 mile. The bean plants all received similar amounts of supplemental fertilizer and water. They were allowed to grow for approximately six weeks during each year at the study 9 a rea. At that time, leaves from each plant in each container were sampled to detennine leaf injury. Wet bulb and dry bulb temperatures at each location for pinto beans
- were measured in 1976,1977, and 1978 each time bean plants were watered.
Data were collected using a portable psychrometer. Utilizing these data, relative humidity and dew point temperature were calculated to aid in
- determining the sphere of influence around the cooling towers.
Analyses of data for vegetation samples collected from 1972 through the 1978 growing seasons continued through the fall and winter of 1978.
- Statistical analyses of data for leaf injury of vegetation has been comple-ted and is discussed in the following sections. Analyses of variance were utilized for all data analyses. When significant (p < 0.05) F-values were O found, Tukey's test was utilized to separate significant (p < 0.05) mean differences.
O RESULTS AND DISCUSSION LEAF INJURY CAUSED BY POLLUTANTS, DISEASE AND INSECTS Natural Vegetation
,
leaves of cheatgrass, kochia, and cottonwood were collected from a maximum of eight locations on four radii at distances of 1/8,1/4,1/2, 9
97 and 1 mile from the St. Vrain Nuclear Generating Station during rapid spring growth (May or June) from 1972 through 1978 (Figure 1). Sampling of kochia and cottonwood at these same locations was again repeated when vegetation was mature in August of each year. Estimates were made for each leaf sampled for total leaf area, leaf area damaged or removed by chewing insects and leaf area spotting caused by air pollutants, disease, nutrition, and sucking insects. 9 Statistical analyses of all leaf data for each year of the study have now been completed. As expected, highly-significant (p < 0.01) differences existed for all leaf measurements among the seven years of data collection. O This indicates the high degree of yearly variation that influences leaf growth and injury. Distance and direction from the generating station were of ten significant (p < 0.05) variables in affecting leaf injury, even O though the generating station was not in full operation. This indicated that microclimatic and site characteristics were natural factors affecting leaf growth and injury rather than relationship to the Generation Station. 9 In general, leaf area of cottonwood increased from May or June through August. Kochia, however, had smaller leaf area per leaf in August of 1974 through 1978. No significant trend in leaf area per leaf for cheatgrass O was found as related to distance from the station. In some years leaves were larger near the generating station, whereas in other years they were larger at the 1/2- and 1-mile distance from the station. Leaves of kochia O tended to be somewhat larger during the seven years of sampling at the 1/2- and 1-mile distance from the generating station. Cottonwood leaves showed sanewhat of an opposite trend, with larger leaves being found nearer O the generating station during five of the seven years of study. This trend, however, was not apparent in 1975 and 1976. O
98 Cheatgrass leaves were larger in a south and southeasterly direction from the generating station in four of the seven years of sampling. Leaves of both kochia and cottonwood often were larger in a southeasterly direction. This may be related to intensive farming and irrigation practices occurring southeast of the generating station during the seven years of the study. O The percentage of leaf area removed by chewing insects increased for both kochia and cottonwood between rapid growth and maturity during 1972, 1974, 1975, 1976, and 1978. This, however, was not true during 1973 and O 1977. Cheatgrass leaf area removed by insects was slightly greater near the generating station than at greater distances. Chewing insects also removed more leaf area of kochia at the 1/8- to 1/2-mile distance from # the power station. In contrast, leaf area missing for cottonwood was somewhat greater at the 1/2- and 1-mile distance from the generating station during most years. Therefore, there was no consistent distance 9 influence from the generating station affecting insect leaf removal among the three species. Removal of cheatgrass leaf area by insects was greater in a south and g southwesterly direction from the generating station in five of seven years of sampling. fio consistent directional trend in leaf area removal among the seven years was found for kochia. Insect feeding activity on cottonwood g le6ves was great in a southerly direction from the station from 1972 through 1974. Trees at this sampling location were cut down in 1975; thereaf ter, insect damage was greater in a southeastern or northerly direction. g Brown tip leaf area of cottonwood was of ten greatest at the 1/2- or 1-mile distance from the station. tio consistent trends in brown leaf tips for cheatgrass or kochia were noted for the four distances from the station , among the seven years of study. O
99 Greater brown tip leaf area for cheatgrass appeared in a northwesterly through southwesterly direction f rom the station f rom 1972 through 1977. This trend was not evident in 1978. However, brown tip leaf area and leaf spotting for kochia was greater by an order of magnitude in 1978 than in previous years. This resulted primarily from collecting and storing leaves when they were too wet. D. jury increased during storage as a result of microbial activity. Brown leaf tips of kochia were also of ten greater in a south through west direction. This same trend was also noted for cotton-wood in six of the sever years of study. This trend might be related to less intensive agriculturil activity in a southwesterly direction from the station. Leaf spotting may be the better indicator of leaf injury caused by pollutants or cooling tower drif t. No significant (p < 0.05) effect as related to distance 'from the generating station was detected for three of the seven years for leaf spotting of cheatgrass. However, leaf spotting of kochia was greatest near the generating station from 1972 through 1974 and in 1978. This was not evident in 1975 when water was not being circulated through the cooling towers. Leaf spotting was greatest near the station for the June collection of kochia in 1976, but spotting was greatest at 1/2-mile by the time of the August sampling period. Leaf spotting of cottonwood, as related to distance from the generating station, was greater at the 1/2- or 1-mile distances in four of the seven years of study. Leaf spotting of cheatgrass was usually greatest in a north, northeast, northwest, and westerly direction from the generating station. Leaf spotting for kochia was usually more pronounced in a nc-thwest and southwest direction O
100 9 from the station. fio trend was detected in leaf spotting for cottonwood as related to direction f rom the generating station. O It appears that leaf injury of the three species during the past seven years has been occurring somewhat at random about the generating station. This was anticipated as the St. Vrain fluclear Generating Station 9 was not yet in full operation. Microclimatic differences, site character-istics, and agricultural activity appear to be the major factors causing the significant distance and directional effects observed to date for leaf 9 injury. These data will be useful in future years to determine if commer-cial operation of the generating station results in greater leaf injury near and downwind from the station. g Pinto Bean Experiment Analysis of data for various leaf characteristics of pinto beans in the controlled experiment indicated that either distance or direction from the cooling towers significantly (p < 0.05) af. tcted all leaf characteristics, except for brown tip leaf area, in at least one of the five years of study. However, significant differences were found aaong the five years of data collection. Leaf area of individual leaves were smaller near the cooling towers (50 feet) in three of the five years of study. Leaf area removed by insects was greater near the cooling towers only in 1976 and 1977; in 1973 O and 1974 missing leaf area was greater at 1/4-mile from the cooling towers. Spotted leaf area was greater near the towers only in 1973; non-significant differences in leaf spotting were found in the other four years as related # to distance f rom the cooling towers. 9 9
101 Larger leaves of pinto beans were found on the east side of the cooling towers in four of the five years of study. However, leaf area utilized by insects was usually greatest on the south side of the cooling towers. No consistent trend during the five years of study was four.d for
"
either leaf area spotted or brown tip leaf area as related to direction from the cooling towers. As expected, highly significant differences (p < 0.01) among years for all leaf measurements were probably caused by differences in growing conditions during the five years of study. Blowers on the towers were usually not in operation and water was only being circulated through the towers during 1973 through 1977. Blowers were in continuous operation in 1978. Ambient environmental conditions surrounding the cooling towers were found to not vary significantly during the study in 1976 and 1977. In 1978, dry bulb temperature was found to increase significantly with distance from the towers. Relative humidity and dew point temperatures were only slightly greater near the towers as compared with data collected at 1/4-mile distance in 1976 and 1978, whereas the reverse was true in 1977. These small differences in ambient conditions probably resulted in only the small differences observed for leaf spotting of pinto beans. Therefore, it would appear that no significant trend is yet apparent as a result of cooling tower presence. These data will be valuable for use in comparison with data collected af ter the station has become fully operational. CONCLUSIONS In general, leaf area injured increased with time during the growing seasons during the seven years of study. This was anticipated as leaves are more susceptible to injury while they are growing and before they reach
102 , maturity. The percentage of leaf area injured for leaves of cottonwood O generally increased with distance from the station. This was sometimes evident in the amount of leaf area spotted or in the amount of brown tip on the end of each leaf. However, leaf injury for kochia appeared to be O slightly greater near the St. Vrain fluclear Generating Station. Most leaf injury measurements for the three naturally occurring species showed significant directional effects. It appeared that leaf injury was slightly greater to the southwest, west, and northwest of the aenerating O station which is not downwind for the prevailing summer wind. Therefore, it appears that variations in leaf injury were caused by microclimate, site and species differences and were little influenced by the generating station
- at the present time.
Leaf area of pinto beans in a control'.ed experiment were often smaller when grown near (50 feet) the cooling towers. However, increased leaf
- spotting near the towers was only observed in one of the five years of study. Cooling tower blowers were usually not in operation during earlier years and humidity near the towers was only slightly greater during 1978
- than at the 1/4-mile from the towers. These relationships may change in 1979 when the generating station becomes fully operational.
O O 0 9
103 MAMMALS, AMPHIBIANS AND REPTILES by Bruce A. Wunder and Laurie Wunder
104 INTRODUCTION AND METHODS The methods and procedures involved in monitoring amphibian, reptile and mammalian populations during this phase of the project are those described in previous progress reports (see Progress Reports May 1 - December 31, 1973 and January 1 - June 30, 1974). Small mammal sampling ,ites were the same as in past years and are indicated in Figure 1. This report is concerned primarily with data gathered during 1978. Tissue heavy metal analyses were not conducted during 1978. RESULTS AND DISCUSSION Mammals: Species Present The species of mammals noted on the Public Service property since 1972 are listed in the yearly progress report for 1976. All species noted were present during 1978, with the exception of those species listed in Table 1 and no new species were noted. Most of the species listed, as not observed this year, have previously been observed only rarely in the area of our study sites, with the exception of the meadow jumping mouse (;'arna izadoonian). In the past, this species has been noted on transect 7 and may currently be suffering from a periodic population low or effects of modifications along transect 7 to Goosequill Pond. Jack rabbits (Lcpaa ap. ) have been seen only in the southwestern portion of the Public Service Company property. We visit this section infrequently, since it is far from our normal study sites. More frequent visits to this area would probably yield a greater number of jack rabbit and thirteen-lined ground squirrel (Spermopitilaa tridccomlineataa)
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106 sitings. Some of the small nocturnal species have never been caught in large numbers, and there is no reason to believe that their absence in our current observations is related to the operation of the Nuclear Generating Station. Although no direct sitings of badgers (Ta.r&!ca tama) were made during 1978, a Public Service Company employee reported seeing an active badger burrow in the vicinity of pumphouse 9, not far from transect 3, during November. We were unable to confirm this observation, however. Cottontail rabbit (Sylvilagua c;,,) activity was high throughout Public Service Company property, as evidenced by frequent sitings during our sampling. A rabbit carcass, found south of transect 3 adjacent to the South Platte River, was positively identified by skull as the eastern cottontail (Sylullama floridauns). The desert cottontail (sylvilagua aufobcnii) may also be present on Public Service Company property, but thus far positive identification of this species has not been possible. Pocket gopher (Caomyo or T;wmcmys) burrows were observed on grid 3 during the late autumn census. Fox squirrels (Sciuras niger) were noted in wooded areas adjacent to transects 5, 7, and 8, near the South Platte River, during all three census periods. A beaver (Castcr canadensia) was observed swimming in Goosequill Pond in April, and another was seen in a slough immediately south of transect 3 in ilovember. Fresh beaver cuttings were observed along Goosequill Pond and adjacent to the St. Vrain River, west of transect 2, in October and flovember. Although fresh beaver sign was noted along the outflow of Goosequill Pond in the spring of 1978, no evidence of recent activity was found during late summer and autumn visits to this area. It would appear that the beaver have shifted the center of their activity
107 8 Table 1. Mammal species previously noted near the St. Vrain tiuclear , Generating Station that were not censused in 1978. Common flame Scientific flame 9
- 1. Shrew Sore cp.
- 2. White-tailed jackrabbit Lepua toencendit 9
- 3. Black-tailed jackrabbit Lepus californicus
- 4. Thirteen-lined ground squirrel Spcmophilus tridccentincatus
- 5. Spotted ground squirrel Spcenophilus spilosoma O
- 6. Rock squirrel Cpcrnophilua variegatus
- 7. florthern grasshopper mouse Onyc;w :ys leucogaater
- 8. florway rat Rattuo norvegicus 9
- 9. Badger Taxidca taxuo
- 10. Meadow jumping mouse l'apac hudsonius
- 11. Long-tailed weasel 1Amtcla frenata 9
9 9 9 e
108 from the outflow of Goosequill Pond to the pond itself during the summer and autumn months. A muskrat (ondatra :ibcchic:4s) was observed on transect 2 in May, and muskrat sign (mounds, feces, tracks), was observed around Goosequill Pond and in a swampy area adjoining transect 2 during spring and autumn census periods. The prairie deg (On qfa hedovicianas) colcny west of the dairy farm was poisoned again in June 1978. Only 6 prairie dogs were seen in July 1978 visit to this area. A December visit to the colony revealed that recovery was still incomplete. Raccoon (Procyon lctor) tracks were commonly seen along the banks of both the South Platte and St. Vrain Rivers during spring through autumn visits to the Generating Station. Skunk (Mephitis maphitis) sign (scats, scent) was noted near transects 3 and 7 and on grids 3 and 2, during all census periods. Rea fox (Valpes vulpes) tracks were seen along the South Platte during the spring census, and a fox burrow was discovered on grid S during the late autumn census. Coyote (Canis latrans) scats were regularly found throughout the study area. These generally contained rabbit fur and a few were observed to contain deer fur. Mule deer (Odocoilcus hemfonus) were observed on transect 5 during the spring census and on the South Platte River flood plain during August through November visits to the g Generating Station. Two white-tailed deer (Odoasilcas viryiniams) fawns were seen near grid 3 and one white-tailed huck was noted near grid 2 in July. Numerous deer track.s were seen along the flood plains of both the South Platte g and St. Vrain rivers during monthly visits to the Generating Station. Mammals: Population Parameters In 1978, the late spring census was conducted from 29 May through 3 June, 9 the early autumn census from 9 September through 14 September, and the late O
109 8 autumn census from 22 November through 27 November. Each census consisted of G 2400 trap-nights. Three hundred and forty-seven animals were captured in late spring, 141 in early autumn, and 125 in late autumn. Of these totals, 283 in late spring,102 in early autumn, and 113 in late autumn were previously 9 unmarked. As in the past, the most abundant species captured were deer mice (Peromyscus maniculatus), house mice (!34s museutua), western harvest mice (Reitimodontomys megalotic), and prairie voles (alicrats ochrogaster). Total numbers of individuals of the four most common species captured during the late spring, early autumn and late autumn censuses for the period 1972 through 1978, are , presented in Table 2. Deer mice remain the most abundant species during all census periods. The deer mouse population appears to have recovered somewhat from the low level
,
reached in late spring and early autumn 1977. Precipitation occurring during the spring of 1978 and concurrent vegetation growth may account for this recovery in spring, although the summer was quite dry. Numbers of deer mice on grid , 3 during the late autumn census were lower than in previous years, however. This may be due to early cessation of breeding due to the dry summer and autumn of 1978. We will need to analyze the mammal reproductive data more closely , to ascertain this. House mice numbers reached a record high during the spring 1978 census period, but dropped to normal levels during the early and late autumn g trapping periods. These population fluctuations in It4s probably reflect changes in agricultural practices and human activity. Grid 1, and to a lesser extent, transect 1, produced particularly high numbers of house mice during , 9
110 the spring 1978 census period. Grid 1 was thickly planted with alfalfa in the spring of 1978 and the increased cover found on both grid 1 and transect 1 probably accounts for the high number of house mice trapped. Ground cover on both grid 1 and transect 1 was substantially reduced during the early and late autumn trapping sessions. Part of transect 1 was burned during the autumn census periods, and much of grid 1 was flooded with irrigation water during the early autumn census. Numbers of house mice and deer mice on transect 4 have continued to decline in recent years, for reasons that remain unclear (Table 3). The plant giowth along the east fence surrounding the Nuclear Generating Station is periodically cleared and the vegetation along the irrigation canal is periodically burned. But there is no evidence that it is burned more often now than several years ago. Thus, the continuing downward trend in numbers may not be simply attributed to an intermittent agricultural practice. The prairie vole population continues to remain at the low levels observed since 1975. In general, western harvest mice numbers have tended to increase since about 1975. This trend continued during the spring and early autumn 1978 census periods. Populations of harvest mice during the late g autumn session dropped considerably from the high level attained during the late autumn 1977 census period, however (Table 2). Two meadow voles (Microtus pc>magluanican) were caught along transect 7, auring the early autumn 1978 9 census. Amphibians and Rectiles: Species Present Table 4 lists the species of amphibians and reptiles which have been 9 observed since 1972 on the Public Service Company's property surrounding the 9
111 # Table 2. Total number of individual small mammals captured at the St. Vrain Nuclear Generating Station. S LATE SPRING Species 1972 1973 1974 1975 1976 1977 1978 g P. maniculatus 142 207 91 202 223 74 109 (deer mice) M. musculus 35 50 11 35 42 13 93 , (house mice) M. oc7mogaster 39 51 109 17 8 1 24 (prairie voles) R. megalotto 0 3 2 4 7 7 57 g (harvest mice) EARLY AUTUMN Species 1972 1973 1974 1975 1976 1977 1978 # P. maniculatus 79 81 129 128 105 48 69 (deer mice) M. musculus 6 17 23 24 15 27 13 # (house mice) M. ochrogaster 62 56 31 11 27 9 7 (Prairie voles) R. megalotis 0 0 0 2 2 12 11 8 (harvest mice) LATE AUTUMN Species 1972 1973 1974 1975 1976 1977 1978 P. maniculatus 74 86 152 189 59 68 60 (deer mice)
+
M. musculus 21 26 45 17 13 64 15 (house mice) M. ochrogaster 12 17 19 0 2 5 7 (prairie voles)
- R. megalotis 0 1 4 17 40 124 31 (harvest mice)
112 Table 3. Numbers of house mice and deer mice captured on transect 4. LATE SPRING ,_. ._
. . _ _
Species 1972 1973 1974 1975 1976 1977 19 7l'
. . . .
P. mcmieu;at.as 22 12 1 8 10 ? O (deer mice) M. muccaluc 22 8 0 5 14 a 2 (house mice)
.
_ EARLY AUTUM'), _ Species 1972 1973 1974 i35 1976 1977 1978
.-
P. maniculatua 9 2 a 1 3 0 0 (deer mice) M. musculua 2 4 10 14 1 2 1 (house mice)
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. i:niculatuu 7 4 0 3 0 2 0 (c2er mice)
M. muaculus 11 14 19 9 1 0 1 (house mice) .
O 113 Table 4. Amphibians and reptiles present in the vicinity of the St. Vrain , Nuclear Generating Station. l Common Name Scientific Name Presence 4
- 1. Spadefoot toad scaphiopus bombifrons 1. V-C
- 2. Great Plains toad Bufo copzatus 2. C
- 3. Woodhouse's toad Bufo uoodhousci 3. C
- 4. Western chorus frog Pseudacris triscriata 4. C
- 5. Bull frog Rana catesbiana 5. C
- 6. Leopard frog Rana pipiens 6. V
- 7. Tiger salamander Ambystoma tigrinwn 7. V
- 8. Snapping turtle Chelydra serpentina 8. D
- 9. Painted turtle Chrysemys picta 9. V-D
- 10. Spiny soft-shelled turtle Trionyx spiniferus 10. V
- 11. Racer coluber constrictor 11. V
- 12. Common garter snake Thxrnophis sirtalis 12. C
- 13. Plains garter snake Thamnophis radix 13. C
- 14. Bull snake Pituophis melanozcacas 14. C
- 15. Western rattlesnake crotalas viridis 15. V 2
- 16. Lesser earless lizard Holbrookia naculata 16. V I G C = captured D = found dead S = scat T = track V = visual observation Identification not positive 4
114 St. Vrain fluclear Generating Station. Several trips were made to the station property in the spring of 1978 in order to inventory amphibians and reptiles. Woodhouse's toads (Bufo coadhvaaci), chorus frogs (Pacadaavia triceviata), and leopard frogs (Rana pipienn) were actively calling during these censuses. A bull snake (Pitaophis melanoleucas), common garter snakes (T;mucphic sivtalis) and a dead snapping turtle (chaludra carpentina) were observed during the spring 1978 small mammal census. During July, two bullfrogs (Rana catechiana) were actively calling at Goosequill Pond and what was probably a lesser earless lizard (Holbrookia rucalata) was observed near grid 2. However, the animal was not captured and identification is only tentative. A spiny soft-shelled turtle (Tvionym spiniferas) was seen at the confluence of the St. Vrain and South Platte Rivers in August 1978. Woodhouse's toads (Bufo uoodhoacai), leopard frogs (Rana pipicns) and garter snakes (Thamno;:his c;>. ) were observed during the early autumn small mammal census. OVERALL C0f4CLUSI0fiS With the exceptions noted above, the same species of mammals, amphibians and reptiles noted during the inventory phase of this project are still present. Although some small mammal populations show yearly variations in numbers, climatological factors and agricultural practices have probably been more important in influencing these numbers than activities of the fluclear Generating Station. At this point we have no reason to believe that functioning of the fluclear Generating Station has adversely affected mammals, amphibians or reptiles on the surrounding property. Once the Fort lint Vrain fluclear Generating Station is commercially operating full time, it will be useful to compare heavy metal levels in mammal and amphibian tissues to those found prior to operation.
115 TERRESTRIAL INVERTEBRATES O by O J. Wayne Brewer O O O 9 O
116 Introduction e Terrestrial invertebrates have been collected from three sites near the Fort St. Vrain Nuclear Generating Station since April 1972 (Figure 1). The sam-ples were used to establish (1) an inventory of the area and (2) baseline 9 population estimates of groups selected for the monitoring phase of the study. Previous reports indicate that minor increases in radiation prob-ably do not adversely affect terrestrial invertebrates (Skaife 1968, 9 Cadwell and Whicker 1972, Noordink 1970 and Bushland 1971), but that tem-perature changes could c.luse important alterations in species and popula-tions (Wurtz 1969). Therefore, terrestrial invertebrate species and 9 study areas were selected that would be most greatly affected by the possible increases in environmental temperature. g Procedures All procedures used have been previously reported (Brewer 1973). This report summarizes data collected from July 1 until December 31, 1978, g and provides a comparison with data collected during the same periods of 1975, 1976 and 1977. Analysis of some material collected during this period is not complete, however, and is not included. 8 Results and Discussion Inventory: The species inventory has been previously reported (Brewer 1973). Analysis of subsequent collections has resulted in the
- addition of the following species to the inventory list.
Hymenoptera Bethylidae:
- Goniozus colurcbianus Ashmead, Epyris myrmecophilus Brues Dryinidae: Not Identified Further.
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,
g 11 5 O Figure 1. Fort St. Vrain Nuclear Generating Station and environs, showing invertebrate collection sites. 9
118 Spheaidae: Didineis sp. Ichneumonidae: Ctenichneumon semicaeruleus Cr. , Protichneumon sp., Eutanyacra spp. (2 species), Coccygomimus pedalis Cresson, Diplazon laetatorius Fabricus Formicidae: Dorymyrmex pyramicus, Formica cinerea Lepida, F. obscuripes, F_. pallidefulva nitidiventris, Lasius murphyi, L_. interjectus, Myrmica sabuleti americana Formicidae: The number of Formicidae collected in pitfall traps during the period covered by this report is presented in Table 1. Species e identifications are not yet complete and will be presented later. The number of individuals collected was highest in July when nearly 5,000 specimens were taken. Thereaf ter, the numbers steadily decreased until g Decembe when there were no Formicidae in the collection. This pattern is typical of many invertebrates since the group is generally less active during periods of low temperature. Over 60 per cent of the individuals e collected were taken from pitfall row two, an area where formicids have been very abundant in previous periods. Population levels were somewhat higher in 1978 than in 1977 but substantially lower than for the same e period of 1976. However, these fluctuations are within the range of numbers collected in previous years. Collembola: A summary of Collembola species collected January 1 - g June 30, 1978, is presented in Table 2. These data were not previously available because species identification was incomplete. In these collec-tions 14 species were taken of the 16 known to occur in the area. The 9 absent species, Sminthurus aureus and Bourletiella arvalis, have been collected infrequently and appear to be quite rare. Eight of the species were taken at three trap lines and seem to be conmon residents of the 9
a 119 Table 1. Number of Formicidae collected from pitfall traps at the Fort St. Vrain Nuclear Generating Station, Platteville, Colorado. July 1-Dec. 31, 1978. e Date Row 2 Row 3 Row 4 Total July 1-8 4,102 423 440 4,965 August 5-12 2,939 792 897 4,627 September 2-9 879 327* 992 2,198 October 7-14 844 256 380 1,480
- November 4-13 555 40 83 678 December 9-16 0 0 0 0 Totals 9,318 1,838 2,792 13,948
- 2 traps flooded by overflow from canal
,
Table 2. Summary of Collembola collected from pitfall traps at the Fort St. Vrain Nuclear Generating Station Site, Platteville, Colorado. Jan.1-June 30,1978. Species Row 2 Row 3 Row 4 Total
- Bourletiella arvalis 0 0 0 0 Entomobrya nivalis 28 1,618 1,255 2,901 Entomobrya unostrigata 12 1 128 141 Entomobryoides guthriei 76 0 0 76 O Hypogastrura armata 0 1,088 1 1,089 Hypogastrura matura 18,650 136,831 212,080 367,561 Isotomurus palustris 1 0 1 2 Lepidocyrtus cyaneus 69 140 1,028 1,237
- Proisotoma minuta 1,204 5,050 19,552 25,806 Pseudachorutes subcrassoides 12 195 516 723 Pseudosinella rolfsi 110 0 768 878 Sminthurides pumilis 89 2 4 95 Sminthurinus elegans 8 16,132 16,132 32,272 Tomocerus vulgaris 25 0 0 25 Xenylla 513 2,688 0 3,201 Total 20,797 163,745 251,465 436,007 O
O
120 area. The other six species, Tomocerus vulgaris, Pseudosinella rolfsi, Hypogastrura armata, Isotomurus palustris, Entomobryoides guthriei and Xenylla sp. , were collected from more restricted areas, although sometimes locally abundant. Overall, the most numerous species was Hypogastera matura, which was abundant in collections from all areas, as in past years. Other common species included Entomobrya nivalis, Proistoma minuta, Sminthurinus elegans and Xenylla sp. The last species was collected in high numbers only from one area, however. The seasonal distribution of Collembola species for the January-June,1978, period was similar to that of past years. Some species, like Hypogastura matura, Entomobrya nivalis, Proistoma minuta and Sminthurinus elegans were represented in samples taken throughout most of the season. Others, like Hypogastrura armata and Lepidacyrtus cyaneus, occurred in high numbers in only one area, or at one sample period, and thus are " rare" species in that regard. Silpha ramosa: This carrion beetle is normally collected in rela- , tively high numbers in pitfall traps. Both the adult and larval forms feed on carrion, mainly small rodents (Brewer and Bacon 1975), and thus are higher in the food chain than many terrestrial invertebrates in the , area. The high populations and food habits of this species make it an important part of the monitoring program. Population levels of adult beetles for this period, with the range , of numbers collected from 1973-1977, are presented in Table 3. Individual collections were generally within the range of those from previous years but total numbers were the lowest taken for comparable periods since the , study began (Table 3). Population levels of immature beetles with compar-able ranges for this period are presented in Table 4. As with the adults, individual collections fall within the range of previous years but total G
Table 3. Number of Silpha ramosa adults collected from each of 3 lines of pitfall traps near the Fort St. Vrain Nuclear Generating Station, Platteville, C0. July 1-December 31, 1978. Figures in parenthesis are ranges of numbers collected 1973-1977. July 8 August 12 September 9 October 14 November 13 December 16 Totals Row 2 0 (0-0) 0 (0-1) 0 (0-0) 0 (0-1) 0 (0-2) 0 (0-0) 0 Row 3 23 (1-83) 59 (0-83) 4 (2-47) 0 (1-103) 0 (0-5) 0 (0-0) 86 Row 4 10 (0-45) 15 (0-55) 1 (1-16) 1 (0-7) 0 (0-1) 0 (0-1) 27 kbtb5 bbfkkhb) 7kfbkbbh bfbbb) kfkkbb) bfbbh bfbkh kkb 1978 1977 1976 1975 1974 1973 Annual Totals _ For This Period 113 185 249 339 81 1/ 80I / Table 4. Number of Silpha ramosa immatures collected from each of 3 lines of pitfall traps near the St. Vrain Nuclear Generatin9 Station, Platteville, CO. July 1-December 31, 1978. Figures in parenthesis are - ranges of numbers collected 1973-1977. S July 8 August 12 September 9 October 14 November 13 December 16 Totals Row 2 0 (0-2) 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 0 Row 3 108 (1-623) 41 (1-147) 6 (0-148) 0 (0-8) 0 (0-0) 0 (0-0) 155 Row 4 44 (0-114) 20 (0-28) 10 (0-100) 0 (0-1) 0 (0-0) 0 (0-0) 74 hotk khbfkb9k) bkfb5bk) kbfk-2kb) b(bb) bfbb) bfbb) 22b 1978 1977 1976 1975 1974 1973 Annual Totals for This Period 229 547 848 475 161/ 5251/ 1/ Collection procedures differed somewhat during 1973 and 1974 and the data may not be directly comparable. G G 0 4 9 9 4 # # # #
122 numbers collected were substantially lower than for any previous compar-able period. Thus it appears that population levels of S. ramosa have declined substantially in the past year. Brewer and Bacon (1975) have suggested that populations of this beetle might be related to the number of small rodents available for food. Data presented by Wunder (1978) indicate a minor decline in rodent numbers did occur in the area during the spring of 1978 which may account in part for the reduction in numbers of S_. ramosa. Araneida: Spiders generally are collected in reasonably high num-bers throughout the year and thus comprise an important part of the moni-toring program, particularly during the winter when most invertebrates are inactive. Seasonal fluctuations in spider populations for this period are shown in Table 5, along with ranges of numbers collected from 1973-1977. The data for this period indicate that individual collections were gener-ally within the range of previous collections. Total population levels were slightly higher than those of 1977 and 1976, though substantially lower than the 1975 level. Thus data continue to indicate a relatively stable spider population exists in the area around the Station. Collec-tiens for the individual sampling dates were similar to past years with numbers gradually decreasing from a high in July to lower levels in December. Tricoptera: The caddisflies are aquatic during the immature stages and therefore would be adversely affected by any changes in water quality or temperature, created by the operation of the Nuclear Generating Station. The short-lived nocturnal adults are attracted to ligFts, and during their brief mass emergences are collected in large nunbers in the black light trap. Populations levels of Tricoptera for this period are shown in Table 6, along with ranges of numbers collected from 1973-1977.
Table 5. Number of Araneida collected from each of 3 lines of pitfall traps near the Fort St. Vrain Nuclear Generating Station, Platteville, CO. July 1-December 31, 1978. Figures in parenthesis are ranges of numbers collected 1973-1977. July 8 August 12 September 9 October 14 November 13 December 16 Totals Row 2 52 (10-151) 52 ( 7-243) 118 ( 5-139) 40 (13-76) 33 ( 6-84) 1 (0-31) 296 Row 3 182 ( 0-288) 120 ( 0-424) 50*(71-220) Row 4 121 (16-140) 40 (15-105) 0 (0-72) 513 451 ( 0-289) 193 ( 0-376) 230 (24-286) 182 ( 5-187) 35 ( 6-328) 1 (0-32) 1092 ______________________________________________________________________________________________________________ Total 685 (34-719) 365 (42-1043) 398 (15-556) 343 (34-391)
*2 traps flooded by overflow from canal 108 (27-517) 2 (G-135) 1901 Annual Totals 1978 1977 1976 1975 19741/ 19731/
for this Period 1901 1389 1861 3237 1074 81 8 Table 6. Number of Tricoptera collected by a blacklight trap near the Fort St. Vrain Nuclear Generating Station, Platteville, C0. July 1-December 31, 1978. Figures in parenthesis are ranges of numbers collected 1973-1977. July 1 August 5 September 2 October 7 November 4 December 9 Totals b 143 (11-1278) 24 (2-6617) 223 (0-293) 1 (0-9) 0 (0-0) 0 (0-0) 391 Annual Totals 1978 1977 1976 1975 19741/ 19731/ for this Period 391 602 177 69 59 2497 Table 7. Number of Heteroceridae collected by a blacklight trap near the Fort St. Vrain Nuclear Generating Station, Platteville, CO. July 1-December 31, 1978. Figures in parenthesis are ranges of numbers collected 1973-1977. July 1 August 5 September 2 October 7 November 4 December 9 Totals 196 (0-2018) 709 (2-1050) 220 (0-186) 0 (0-5) 0 (0-0) 0 (0-0) 1125 Annual Totals 1978 1977 1976 1975 19741/ 19731# for this Period 1125 2997 989 77 188 1802 1/ Collection procedures differed somewhat during 1973 and 1974 and the data may not be directly comoarable. g g e e S 9 4 O 8 8 8
124 Because emergence occurs so sporadically, it is difficult to accurately estimate populations based on limited collections. However, the data available indicate that Tricoptera populations were generally comparable to those of previous years. The total number collected was somewhat lower than for the comparable period of 1977 but substantially higher than for the two previous years. It appears that the populations are relatively stable in the area around the Generating Station. The seasonal emergence patterns have been remarkably similar for all collection periods since the study began. Heteroceridae: The mud-loving beetles live in the mud shores of ponds and streams. Like the Tricoptera they would be affected by changes in water quality or temperature. Also, the nocturnal adults are collected in large numbers in the black light trap. Population levels of this g group are presented in Table 7 along with ranges of numbers collected for 1973-1977. Populations of this group declined in 1974 and in 1975 only 78 specimens were taken. Since that time levels have generally increased although the number of individuals collected in 1978 declined considerably from that of 1977. However, the 1977 level was the highest since the study began. As with the Tricoptera, it is difficult to estimate popula-9 tion levels accurately with limited samples but the available data indi-cate that populations are remaining relatively stable in the area. S93sonal emergence patterns for the six years of the study are reasonably 9 similar. 9 9
125 9 References Brewer, J. W., and T. R. Bacon. 1975. Biology of the Carrion Beetle,
- Silpha ramosa Say. Annals of the Entomological Society of America. 68:786-790.
Brewer, J. W. 1973. Terrestrial Invertebrates. In: Progress Report: Monitoring Fort St. Vrain Nuclear Generating Station for Public Service Co. of Colorado. Thorne Ecological Institute. Boulder, ' Colorado. Bushland, R. C. 1971. Sterility principle for insect control: Historical development and recent innovations. In: Sterility Principle for Insect Control or Erradication. IAEA. (Available O from UNIPUB Inc., Box 433, New York) 542 p. Cadwell, L. L. and F. W. Whicker. 1972. The anthropod community. In: Radioecology of some natural organisms and systems in Colorado, tenth annual progress report on Atomic Energy Commission contract. (Available from Department of Radiology and Radiation , Biology, Colo. State Univ. , Ft. Collins) 84 p. Noordink, J. Ph.W. 1970. Irradiation, competitiveness and the use of radioisotopes in sterile male studies with the onion fly, Hylemya antiqua (Meigen). In: Sterility principle for Insect Control or Erradi cation. IAEA. Vienna. (Available from UNIPUB Inc., Box , 433, New York) 542 p. Skaife, S. H. 1968. Experiments on the effects of radiation on ants. Australian Natural History. March 27-28. Wunder, B. A. 1978. Mammals. In: Progress Report: Ecological g Monitoring Fort St. Vrain Nuclear Generating Station for Public Service Company of Colorado, Thorne Ecological Institute. Boulder, Colorado. Wurtz, C. B. 1969. The effects of heater discharges on freshwater benthos. In: Biological aspects of thermal pollution. Krenkel, g P. A. and F. L. Parker, Editors. Vanderbilt U. Press. Nashville, Tennessee. 4 0 0}}