Study On The Ecology Of Benthic Algae In Freshwater Lakes

Colonizations of benthic microalgae on artificial substrata were compared in two locations of Lake Donghu with different nutrients status, and analyzing the relationships of colonial patterns of benthic algae and nutrient state, temperature. Meantime, spatial and temporal variation of benthic algae community was investigated in Lake Donghu. In spring, benthic algal communities of 28 lakes from Yunnan, Hubei and Zhejiang provinces were investigated, and the relationships between community structures of and major environmental variables were explored. At last, we studied the function of benthic algae in ecosystem of eutrophic lake, the primary productivity of benthic algae and the role of periphyton in phosphorus retention were investigated in a littoral zone of shallow lake.Compared with the colonial characteristic of benthic algae in different conditions, the results of this study indicate that nutrient concentrations and temperature strongly influenced the course of colonization. Site Niuchaohu with lower nutrients had longer lag phase, longer time to mature community, lower peak biomass, lower succession rate; benthic algae community was dominated by diatoms, Achnanthes minutissima controlled the diatoms community at last, and several filamentous green algae found. Site Shuiguohu with higher nutrients concentrations: shorter lag phase, shorter time to mature community, higher peak biomass, higher succession rate; in the early stage of the colonization diatoms community dominated the space, Melorsira varians was important species, and only one filamentous green algae in later community. Compared with spring community, the autumn colonization was characterized with longer time to reach peak biomass, higher peak biomass, unstable community.