Response of a Phytop ankton Community to Contro led Partia Recovery from Experirnenta Acid ification Can. J. Fish. Aquat. Sci. Downloaded from www.nrcresearchpress.com by Guangzhou Jinan University on 06/06/13 For personal use only.
D. L. Findlay and S. E. M. Kasian Department of Fisheries and Oceans, Central and Arctic Region, Freshwater Institute, 505 University Crescent, Winnipeg, Man. R3T 2N6, Canada
Findlay, D. b., and S. E. M. Kasian. 1991. Response of a phytoplankton corrlmur~ityto controlled partial recovery from experimental acidification. Can. ). Fish. Aquat. Sci. 48: 1022-1829. Lake 223 was experimentally acidified with H,S8, from 1976 to 1989. The pH was reduced from 6.7 (1974) to 5.0 (1981) and held there for 3 yr (1981-83j. Beginning in 1984 the pH was allowed to increase at a controlled rate by reduction of acid additions, resulting in a two-step recovery of 4 yr at pH -5.5 and 2 yr at p H -5.8. During the first 6 yr of early recovery, species diversity of the phytoplankton community increased linearly with pH and the number of common species increased. Total phytoplankton biomass remained elevated above preacidification estimates or increased. Dinoflagellates and cyansphytes remained codominant with little evidence of other taxonomic groups increasing. De 1976 a 1989, le lac 223 a 6te artificiellement acidifik. be pH est passe de 6,7 en 1974 21 5,O en 1981; il a et$ maintenu 2I ce niveau pendant 3 ans, soit de 1981 2I 1983. En 1984, le pH a et6 graduellement augment6 21 un taux contr6l6 par reduction des ajouts d'acide pour obtenir un retablissement du pH en deux &apes, soit 4 ans 3 ken pH d'environ 5,s et 2 ans 3 un pH d'environ 5,8. Au cours des six premiitres ann6es du r6tablissemewt, la diversit6 des espkes de la comrnunaut6 phytoplanctonique a augmente de f q o n lin6aire en fonction d'une augmentation du pH et le nornbre d'espitces communes a augmentk. La biomasse totale de phytoplancton est demeur6e sup6rieut.e aux estimations effectu6es avant I'acidification ou a augrnent6. kes dinoflagelles et les cyanophycees sont demeurks codominants et les autres groupes taxonomiques ne se sont pas rev6l6s plus abondants. Received April 2, 1990 Accepted December 7 7, 1990
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cid precipitation caused by sulfur and nitrogen emissions continues to be a major perturbation of freshwater ecosystems. The only available literature on phytoplankton population responses to recovery from acidification me palesllimnological studies (Dixit et al. 1989) and experiments where a technique r e f e n d to as "liming" has been applied (Scheider et al. 1976; Yan and Dillsn 1984; Hultberg and Andersson 1982). After liming two lakes in the Sudbury area, Scheider et ale(1976) documented am immediate increase in biomass m d a shift in dominance to chrysophytes. However, Hultberg and Andersson (1982) documented a slow recovery response over 5 yr for four limed lakes in Sweden. Neither of these studies had preacidification data against which to compare recovery results. In this study, a whole-lake acidification experiment was begun in 1976 on Lake 223 at the Experimental Lakes Area (ELA) (Schindler et a1. 1988, 1985; Findlay and Kasiam 1986). The phytoplankton community was monitored intensively for 2 yr prior to acidification (1974 -75) and for 14 consecutive yr during acidification. The pH in Lake 223 was reduced gradually from 6.7 (I 974) to -5.0 (1981-83) by epilimnetic additions of H,SO,. The responses of the Lake 223 epilimnetic phytoplankton community to decreasing pH (Findlay 1984; Findlay and Kasian 1986, 1990) were similar to those observed in other studies involving both enclosure experiments and atmosphericaly acidified lakes (Almer et al. 1978; Kwiatkowski and Roff 1976; Y m and Stokes (1978), In its natural state (1974 -75) the phytoplankton community in Lake 223 was comparable with other natural ssystems in the EEA (Findlay and Kasian 1990). Species diversity
was high with a chysophycean dominated assemblage accompanied by smaller populations of diatoms, chlsmphytes, and cryptophytes. Biomass at this time averaged 650 gam-" which was typical for lakes in this area. Decreasing pH caused a shift in species composition to a predominance of dinoflagellates m d cyanophytes. Species diversity decreased by 3096, phytoplankton biomass increased by 48%, and the portion of phytoplankton biomass 40 pm) has remained elevated or increased. This group is composed sf several species of large silicious dinoflagellates and some colonial chqsophytes. The combination of size and palatability of these dominant species may affect interactions between phytoplankton and zooplankton populations in Lake 223. Further investigations are required to resolve these interactions.
Conclusion We conclude that species diversity of the phytoplankton comunity in Lake 223 has begun to recover at pH 5.5-5.8. However, the phytoplankton community assemblage and abund a c e still resembles one of an acidic environment. Species dominant in the lake prior to acidification have not successfully colonized the lake in spite of ample seed populations. We have shown that the early recovery process for the phytopladcton comunity is not the exact inverse of acidification. Based on the results of Hultberg and Andersson (1982) md Scheider et d.(1976), we expect that full recovery will occur when pH is allowed to increase to a circumneutrd level for 2-4 yr. 'This will cause acidophilic species to decline in abundance to a level sufficient for circurnneutral species to reestablish their dominance.
E. DeBmyn supplied us with p h y t o p % ~ t osamples n in conjunction with his primary productivity program. We appreciate the criticism provided by K. MiBBs, B. Eiecky, R. Hessllein, J. Shearer, and H. Kling during preparation of this rnmuscript. This work was supported by the Department s f Fisheries and & e m (Canada).
References ALMER,B . , W. DICKSON, C. EKSTROM, AND E. HORNSTROM. 1978. Sulfur pollution and the aquatic ecosystem, p. 271-31 1. In B. Nriagu bed.] Sulfur in the environment. Part 2. John Wiley and Sons, New York, NY. ARMSTRONG, F. A. J., AND B. W. S C H I ~ ~197 R1.. b l i m i n q chemical characterization of waters in the Experimental Lakes Area, northwestern Ontario. J. Fish. Res. Board Can. 28: 171-187. CLEUGH, T. R., AND B. W. HAUSER. 1971. Results of the initial survey of the ExperimentalLakes Area, northwestern Ontario. J. Fish. Res. Board Can. 28: 129-137.
Can. 3. Fish. Aqmt. Sci., Val. 48, 1991
CRU~HAN D.KR. , 1984. Whole lake chemical additions in the Experimental Lakes Area, 1969-1983. Can. Data Rep. Fish. Aquat. Sci. 449: iv 23 p. 1986. Whole lake chemical additions in the Experimental Lakes Area, 1984 -1986. Cam. Data Rep. Fish. Aquat. Sci. 588: iv + 10 p. BIXIT,S. S., A. S. DIXIT,AND J. P. SMOL.1989. Lake acidification recovery can be monitored using chrysophycean microfossils. Can. J. Fish. Aquat. Sci. 46: 1309-1312. FHNDLAY, D. L. 1984. Effects on phytoplankton biomass, succession, and csmposition in Lake 223 as a result d lowering pH levels from 5.6 to 5.2 data from 1980 to 1982. Can. MS Rep. Fish. Aquat. Sci. 1761: iv 10 p. FINDLAY, D. L., AND S. E. M. KASBAN. 1986. Phytoplankton responses to acidification of Lake 223, Experimental Lakes Area, northwestern Ontario. Water Air Soil Pollut. 30: 719-726. 1987. Phytoplankton community responses to nutrient additions in Lake 226, Experimental Lakes Area, northwestern Ontario. Can. J. Fish. Aquat. Sci. 44(Suppl. 1): 35- 46. 1990. Freshwater phytoplankton communities of Iakes expenmentally acidified with sulfuric and nitric acids. Cm.J. Fish. Aquat. Sci. 47: 1378-1386. HEALEY, F. P. 1973. Characteristics of phosphsms deficiency in Anabaena. J. Phycol. 9: 383-394. 1975. Physiological indicators of nutrient deficiency in algae. Fish. Mar. Sew. Res. Dev. Tech. Rep. 585: 38 p. HULTBERG, H., AND I. B. ANDERSSON. 1982. Liming of acidified lakes: induced long-tern changes. Water Air Soil Pollut. 18: 3 11-33 1. KWIATKOWSH, R. E., AND I. C. Row. 1976. Effects of acidity on the phytoplankton and primary productivity sf selected northern Ontario lakes. Can. J. Bot. 54: 2546 -2561. NAUWRCK, A. 1963. Die beziehkmngen zwischen zooplankton und phytoplankton in see Erken. Symb. Bot. Upsal. 17: 163 p. PROKO~WK J. C1979. H , Chemical characterization of epilimnetic waters of unenriched Iakes in the Experimental Lakes Area, northwestern Ontario. Can. Fish. Ma.Sen. Tech. Rep. 873: iv + 41 p.
[email protected]. SAS user's guide: statistics. Version 5 edition. SAS SAS INSTITUTE Institute Inc., Cary, NC. 956 p. ~CHEIDER, W. A., B. CAVE,AND J. JONES.1976. Reclamation of acidified Bakes near Sudbumy, Ontario, by neutralization and fertilization. Ontario Ministry of the Environment, Toronto, Ont. 54 p. SCHINDLER, 5. W. 1974. Eutrophication md recovery in experimental lakes: implications for Iake management. Science (Wash., DC) 184: 879-899. SCHINDLER, DoW., K. H. MILLS,B. F. MALLEY,D. L. FINBEAY, B. A. I. J. DAVES,EM. A. TURNER, G . A. LINDSEY, AND D. R. CRUIKSHEARER. SHANK. 1985. Long-tern ecosystem stress: the effects of years of experimental acidification on a small lake. Science (Wash., DC) 228: 13951401. SCHINDLER, D. W., R. WAGEMANN, R. B. COOK,T. RUSZCZYNSKI, AND J. h 0 ~ 0 P O w r e ~1980. . Experimental acidification of Lake 223, Exprimental Lakes Area: background data and the first three years of acidification. Can. J. Fish. Aquat. Sci. 37: 342-354. SHEARER, J. A. 1978. Two devices for obtaining water samples integrated over depth. Can. Fish. Mar.Sew. Tech. Rep. 772: iv 9 p. VOLLBNWEIDER, R. A. l96SQScientific fundmentais sf the eutrophication of lakes and flowing waters, with particular reference to nitrogen and phosphsms as factors in eutrophication. Tech. Rep. Q.E.C.B. Paris Das/CSP/ 68.27: 1-182. WASHINGTON, H. G. 1984. Review: diversity, biotic and similarity indices. A review with special relevance to aquatic ecosystems. Water Res. 186: 653494. WATERS, T. F. 1956. The effects of lime application to acid bog lakes in northern Michigan. Trans. Am. Fish. Soc. 86: 329-344. YAN,N. E., AND P. J. DILLON.1984. Experimental neutralization of lakes near Sudbanry, Ontario, p. 41%- 456. In J. R. Nriagu [ed.] Environmental impact of smelters. Vol . 15. John Wiley and Sons, New York, NY. YAN, N. E., AND P. STOKES. 1978. Phytoplankton of an acidic lake, and its responses to experimental alteration of pH. Environ. Consem. 5: 93-100.
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