| 引用本文: | 刘恩生,刘正文,陈伟民,陈开宁.太湖鱼类产量、组成的变动规律及与环境的关系.湖泊科学,2005,17(3):251-255. DOI:10.18307/2005.0310 |
| Liu Ensheng,LIU Zhengwen,CHEN Weimin,CHEN Kaining.Changes in the Yield and Composition of the Fish Catches and Their Relation to the Environmental Factors in Lake Taihu. J. Lake Sci.2005,17(3):251-255. DOI:10.18307/2005.0310 |
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| 摘要: |
| 通过2003年9月-2004年1月的渔获物调查,并结合1984-2002年的鱼类产量统计资料,分析了近二十年来太湖鱼类产量和组成的变化规律以及环境间的相互作用关系.结果表明,太湖鱼类的种类在不断减少,如本次调查和2002年3月-2003年12月的调查只采集到48种鱼类,和历史资源料比较有55种鱼类难以采到;鱼类产量组成表现为仅鲚鱼的产量和组成比例总体呈较快的上升趋势,从1984年的5153.7t、占总产量的36.2%上升到2002年的19571t、64.1%,鲤、鲫鱼基本维持不变,但近四年略有上升,其余鱼类均呈下降趋势.用Wilhm改进式计算的鱼类产量组成的均匀度指数H总体呈逐年下降趋势,近二十年来平均以每年-0.0465的速率下降;分析认为,人类活动以及由此引起的太湖生态环境变化,包括江湖阻隔、过渡捕捞、富营养化及太湖特有的鱼类生态学特点决定了鱼类组成的这一变化趋势:江湖阻隔、过度捕捞是引起太湖鱼类种类减少和鱼类组成发生巨大变化的主要原因;太湖近二十年来富营养化程度不断加重,由此使初级生产力水平持续增长,浮游生物饵料丰富,使鲚鱼等浮游生物食性鱼类产量逐年提高;舶鱼数量的减少又使鲚鱼失去抑制.随着鲚鱼等浮游动物食性鱼类产量的升高,太湖浮游动物的生物量呈下降趋势,这可能是太湖浮游植物数量倍增的生物学因素之一.目前太湖鱼类产量组成的变化正向着抑制浮游动物和有利浮游植物生长的方向发展. |
| 关键词: 太湖 鱼类产量 鱼类产量组成 |
| DOI：10.18307/2005.0310 |
| 分类号: |
| 基金项目:中国科学院知识创新工程重大项目(KZCX1-SW-12-IV)国家"863"项目(2002AA60101)和(2002AA601013) |
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| Changes in the Yield and Composition of the Fish Catches and Their Relation to the Environmental Factors in Lake Taihu |
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Liu Ensheng1,2,3, LIU Zhengwen2, CHEN Weimin2, CHEN Kaining1,2
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1.Graduate School of CAS, Beijing 100039, P. R. China;2.Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, P. R. China;3.Anhui Agicultural University, Hefei 230036, P. R. China
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| Abstract: |
| Based on the catches from 1984 to 2002 and the present investigation from September 2003 to Januaiy 2004 and the last investigation from March 2002 to December 2003, the changes in fish species composition and yield in Lake Taihu were analyzed in relation to the environmental factors of the lake. The results showed that only 48 fish species were found during the present investigation and the last investigation. Compared with 103 fish species recorded in historical data, there was 55 fish species difficult to be collected. The changes in the yield and the composition of fish catches showed the trend that only Coilia spp. had increased in their percentages in the fish catches from 5153.7t accounting for 36.2% of total fish catches in 1984 to 19571t accounting for 64.1% in 2002; the percentage of Cyprinus carpio (Linnaeus) and Carassius auratus (Linnaeus) had been rather stable, but it began to increase in recent years while that of most other species had declined. The evenness index H decreased at the annual averaged rate of -0.0465. Analysis of fish compositions showed that, human activities such as the obstnicted between river and the lake, overfishing, environmental pollution and the ecological characteristics of the fishes were responsible to the changes in fish catches of Lake Taihu. The obstructed between river and the lake and over fishing were the main reasons of the decline of fish species and the changes of fish composition. The catches increasing of Coilia spp. were caused by eutrophication resulting in plankton increasing and got out of control for the decline of carnivores fishes topmouth culter (Erythroculter ilishaeformis Bleeker and Erythroculter mongolicus Basilewsky). With the catches increasing of Coilia spp., there was the trend of zooplankton standing mass decline in the lake. So the changes in fish catches of Lake Taihu probably enhanced phytoplankton development in the lake. |
| Key words: Lake Taihu total fish catches composition of fish catches |
