Community dynamics of algae and limiting nutrient in Taipinghu Reservoir

Abstract

本文报告了1992~1993年间对安徽省太平湖水库藻类的演变以及库水营养侦别试验的研究结果。与1985~1986年资料相比,整个水库的藻类种类多样性下降,总种类数由175种降为112种,减少了1/3。藻类种类小型化现象十分明显,相隔6~7年,小型藻类的种类及其数量越来越多,单个藻细胞鲜重的平均值在敞水区和库湾区分别减少了63.6%和75.4%;平均细胞密度则分别增长了3.6和5.6倍;生物量的变化不大,增长不足1倍。营养侦别试验结果表明,磷仍然是该水库的主要限制因子,库水的藻类生长潜力约为对照培养基的1/4。;The paper represents the results of a successive study on the succession of algal community and the changes of algae number as well as the limiting nutrient for algae growth in Taipinghu Reservoir during 1992~1993. As comparied with the previous data(1985~1986) by the author, it is decreased in the species diversity of algae with more than 30% reduced in the total species number, and the species of micro algae is increased notably. The mean wet weight per algae cell is reduced by 63.6% in pelagic zone and 75.4 in bay area after an interval of about 7 years. However, the mean annual cell densities in pelagic zone and bay area are increased by 3.6 and 5.6 times respectively. According to the results of nutrient spikes, it is possible that phosphorus is still a limiting factor to aJgae growth. The AGP of the reservoir is only equal to 25% of the HB T-5 control medium.