摘要
根据1973—1975年对东湖底栖动物的调查研究结果,列出了31种东湖底栖动物的名录,比较了各湖区各类动物的现存量及其在不同年份的变动情况,进而估算了全湖底栖动物资源的蕴藏量。此外还分析了7个优势种在现存量中的意义及分布型式。环境分析表明:底栖动物的密度有随水深的增加而递减的趋势。昆虫和寡毛类在密度和生物量方面从属于湖水中总氮和总磷的含量,它们的生物量与湖水的有机物耗氧量也有从属关系。对以上关系进行了简单的数学描述。讨论了底栖动物在渔业上的合理利用问题,测算了湖中底栖动物的供饵能力,提出了青鱼和杂食性鱼类的增放量。从水质生物监测的角度,根据底栖动物的密度或生物量推算出五项生物指标数值,对各湖区污染程度和年变化情况作了初步评价。
Investigations on zoobenthos in Lake Dong Hu (Tung-Hu) of Wuhan, HubeiProvince, were undertaken during 1973-1975. The results may be summarized asfollows: 1. Zoobenthic community of the Lake is chiefly composed of 5 species of aquaticoligochaetes, 15 species of molluscs and 12 genera of aquatic insects. Among them,Branchiura sowcrbyi, Limnodrilus hoffmeisteri, Bellamya aeruginosa, Parafossarulusstriatula and the Chironomid species belonging to the genera Pelopia, Procladius andEinfeldius are predominant. 2. The annual standing crops of zoobenthos in the Lake during the surveyingperiod were 362-462 ind. m^(-2) in density and 38.2-72.1 gm^(-2) in biomass. It was foundthat the standing crops were lower in June-July and higher after October in each year. 3. Standing crops varied with the three subregions of the Lake. Higher valueswere always obtained in the subregion Shuiguohu, a bay receiving a larger amount ofsewage water, while the lower values were found in the subregion Guozhenghu, thelargest openwater area in the Lake. 4. Standing crops including oligochaetes and insects in various subregions werefound to be correlated positively to the total nitrogen and to the total phosphorus inthe water. Regression formulae calculated from biological and environmental variablesshowed that both density and biomass of the animals would increase exponentially whenphosphoric compounds increase even at ppb level and thus total phosphorus is consi-dered to be the most important factor limiting the abundance of the benthic macroin-vertebrates. 5. Suggestions concerning fishery management and water quality monitoring ofthe Lake based on some zoobenthic parameters are offered.
