长荡湖水生植被动态及其渔业效应的研究

本文根据1983年—1984年调查研究结果分析整理而成。文中论述了长荡湖现有水生植被的种类组成,群落结构,生态分布,沉水植物的生物量及其利用。经过分析比较,发现近30年来,长荡湖水生植被经历了旺盛—衰竭—恢复—旺盛的演替过程,揭示了引起植被变化的各种因素。随着水生植被的动态变化,长荡湖的鱼类种群结构,渔获对象及捕捞工具都相应发生了变化。植被的盛衰同浮游植物和浮游动物、底栖生物的消长丰歉有着密切的关系.本文最后指出了长荡湖水植被的演替趋势和潜在危机,强调了合理利用和定向改造水生植被的重要性,并对今后如何发展我国湖泊渔业提出了建议。

ON THE DYNAMICS OF THE AQUATIC YEGETATION IN CHANGDANG HU LAKE WITH REFERENCE TO FTSHERY EFFECT

Changdang Hu Lake, situated in Jiangsu province, is a shallow lake(average water depth 1.0 meter) with an area of 90 square kilometres. The lake isrich in submerged plants, about 70% is covered by Potamogeton maackianus Benett.There are altogether 60 species of fishes in the lake, and the total fish yield in 1983is 11.5 tons about 0.68 kg/ha. The paper is a result of investigation in 1983-84. Data concerning the speciescomposition, community structure, ecological distribution and submerged plantsbiomass of the aquatic vegetation are reported. The succession of the aquatic vegetation leads to the dynamic changes of thepopulation structure of fishes, the abundance of phytoplankton, zooplankton andthe benthos. By analysing the data, it was found that the aquatic vegetation inChangdang Hu Lake has followed a long succession from richness to declination,from recovery to richness during the last thirty years. Accompanying with thesuccession, the changes of fish composition, fish stocking and fishing gear havealso occured. Basing on the viewpoint of lake ecology, the paper emphasized the importanceof the submerged vegetation resource, and implied the possible succession trendsof Changdang Hu Lake fishery ecosystem. Lastly, some suggestions on develop-ment of lake fishery have been made.