摘要
于2005年5月和11月调查了横岗水库的营养盐、叶绿素a(Chl.a)和浮游植物,对水库富营养化特征进行了分析。5月的总氮(TN)平均浓度为3.810mg?L-1,总磷(TP)平均浓度为0.172mg?L-1,Chl.a平均浓度为17.888mg?m-3,综合营养状态指数(TSIM)为73.3,该水库已达重度富营养化;11月份TSIM下降到55.6,处于轻度富营养化状态,TN和TP平均浓度分别下降到1.302mg?L-1和0.096mg?L-1,Chl.a平均浓度却上升到26.935mg?m-3,Chl.a浓度的上升与氨氮(NH3-N)和正磷(PO4-P)浓度上升以及浮游植物群落组成改变有关。从5月到11月,水库由蓝藻型富营养化水体变为绿藻型富营养化水体。5月浮游植物平均细胞密度高达2.75×108cells?L-1,优势种为美丽平裂藻和银灰平裂藻,其中平裂藻细胞数约占总细胞数的90%。11月浮游植物平均细胞密度降低到1.27×107cells?L-1,平裂藻的优势度下降,只占总细胞数的14.89%,绿藻成为主优势类群,其中栅藻是优势种之一,占总细胞数的11.52%。
The nutrients, chlorophyll a andphytoplankton in the Henggang Reservoir were monitored in May and November, 2005. In May, the mean concentration of TN, TP and Chlorophyll a were 3.810 mg·L^-1, 0.172 mg·L^-1 and 17.888 mg·m^-3. respectively. Comprehensive Trophic State Index （TSIM）, was 73.3, indicating that the Reservoir was hypertrophic. In November, the mean concentration of TN and TP were 1.302 mg·L^-1 and 0.096 mg·L^-1, respectively. The TSIM decreased to 55.6, indicating that the Reservoir was lightly eutrophic. However, the mean Chlorophyll a increased to 26.935 mg·m^-3. The increase of chlorophyll a concentration was positively related to NH3-N and PO4-P, and changes in phytoplankton community composition. The phytoplankton community was dominated by Cyanophyta in May, but by Chlorophyta in November. In May, the mean cell abundance of phytoplankton was 2.75×10^8 cells·L^-1. The dominant species were Merismopedia elegans and M. glauca, which composed about 90% of the total phytoplankton. In November, the mean cell abundance of phytoplankton was 1.27×10^7 cells·L^-1. The dominance of Merismopedia reduced to 14.89% of total phytoplankton cells. Scenedesmus became one of dominant svecies, which composed 11.52% of total phytoplankton cells.
出处
《生态科学》
CSCD
2006年第5期445-449,共5页
Ecological Science
基金
教育部骨干教师基金
优秀青年教师基金
关键词
富营养化
浮游植物
营养盐
横岗水库
Eutrophication
Phytoplankton
Nutrients.Henggang Reservoir
