硫酸盐对淡水浮游藻类群落结构的影响研究

Effects of Sulfate on the Community Structure of Phytoplankton in Freshwater

为了解硫酸盐含量增加对富营养化淡水水体藻类生长及群落演替的影响,对天津市某景观水体藻类进行了室内模拟试验研究.按硫酸盐投加方式分设对照组(G0)、逐步投加组(G1)和一次性投加组(G2).结果表明,向水中投加一定浓度硫酸盐可以抑制原有蓝藻和硅藻生长,而绿藻种类和生物量增加.G0和G1组的种类数和生物量相近但是大于G2组.G0、G1和G2组的平均总生物量分别为98.46、96.09和81.19 mg.L-1.对照组几乎始终是皮状席藻(P.corium)和两栖颤藻(O.amphibia)等蓝藻为第一优势种,而投加硫酸盐的G1和G2组优势种从皮状席藻和小颤藻(O.tenuis)等蓝藻向四尾栅藻(S.quadricauda)、放射多芒藻(G.radiate)和斜生栅藻(S.obliqus)等绿藻演替.群落平均多样性指数与对照组G0(1.49±0.32)相比,投加硫酸盐的G1(1.70±0.18)与G2组(1.68±0.40)均有提高.

In order to promote the understanding of sulfate enrichment on the growth and succession of phytoplankton communities in eutrophic freshwater body, laboratory experiment of phytoplankton in a landscape water body was conducted. Three treatment groups were set up in experiment： control （GO）, step by step enrichment （G1） and enrichment at a time （G2）. The result indicated that the addition of sulfate promoted the increase of Chlorophyta species and biomass, while inhibited the growth of native Cyanobaeteria and diatom species. Species and biomass of GO, G1 group were similar and much higher than those of G2 group. Average biomass of GO, Gland G2 group was 98.46, 96.09 and 81.19 mg·L^-1 , respectively. GO group was almost always dominated by Cyanobaeteria species such as P. corium and O. amphibia, dominant species in G1 and G2 groups changed from Cyanobacteria species to Chlorophyta species including S. quadricauda, G. radiate and S. obliqus. Compared with that of control group GO （1.49 ±0.32）, the average community diversity indices of G1 （1.70±0.18）and G2 groups （1.68 ±0.40） were elevated.