南亚热带调水水库春季浮游植物群落的结构与动态

Dynamics and Structure of Phytoplankton Community in Spring in a Southern Subtropical Pumped-water Reservoir

于2005年1-6月,对南亚热带调水水库—大镜山水库的水文、营养盐(N、P)和浮游植物进行了调查研究。共检测到浮游植物76种;浮游植物总的细胞数量在4.925×106-63.65×106cellsL-1之间,浮游植物的总生物量在1.632-20.420mgL-1之间。假鱼腥藻(Pseudanabaena sp.)是主要优势藻,但是早春(1-3月)假鱼腥藻和肘状针杆藻(Synedraulna)共同成为优势藻。浮游植物细胞的丰度晚春(4-6月)比早春的要高,但是生物量却比早春的低。在水文过程与其它水库有一定差别的典型调水水库,水温是引起浮游植物种类组成变化的主要原因。浮游植物组成与动态是受入库营养盐和水动力学的变化所影响的。

The effects of hydrology and nutrients （N and P） on the phytoplankton community were studied in a southern subtropical reservoir, the Dajingshan Reservoir, during January to June in 2005. Seventy-six species of algae were identified. The total abundance of the phytoplankton ranged from 4.925× 10^6 to 63.65× 10^6 cells L^-1 and the total biomass from 1.632 to 20.420 mg L^-1. Pseudanabaena sp. and Synedra ulna were dominant species in the community during January to March （the early spring）. Only Pseudanabaena sp. was dominant during April to June （the late spring）, and S. ulna decreased rapidly in number due to water temperature. The phytoplankton abundance in the late spring （April to June） was higher than the early spring; however, its biomass was reverse. Water temperature was the most important factor for the changes of species composition and phytoplankton dynamics in the pumped storage reservoir, in which the phytoplankton community is regulated in a way distinct from other reservoirs. Nutrient loading and hydrodynamic changes affected the composition and dynamics of the phytoplankton.