【作者】 刘凯；

【导师】 施炜纲；

【作者基本信息】 南京农业大学 ， 渔业， 2007， 硕士

【摘要】 本文主要对长江下游渔业群落多样性现状进行了研究,并初步评价了实施长江春季禁渔对长江下游江段渔业群落多样性的影响。对2004-2005年长江下游渔业群落特征和同期渔业捕捞量分别进行了描述和统计,并对各监测点相关指标进行了比较。该群落共计出现渔业生物82种,分别隶属于14目32科66属,主要栖息类型为淡水定居性种类,单位重量小于100g的小型种类占优势,群落优势种为长春鳊、鲫和凤鲚。群落多样性指数分别为:Margalef指数6.46、Shannon-Wiener指数2.41,Simpson指数0.14,Pielou指数0.55。单船年均捕捞量为5519.2kg。对1999-2005年4-6月间崇明江段渔业群落进行研究,并对春禁前后相关指标进行对比分析。研究期内崇明江段共计出现渔业生物37种,分别隶属于12目22科33属。春禁后群落主要优势种为凤鲚、银鲳和棘头梅童鱼,单位重量小于20g的小型种类占绝对优势,鱼类幼体所占比例极大。多样性特征值平均指标为:Margalef指数1.50,Wilhm改进指数1.83,Simpson指数0.24,Pielou指数0.72。对2000-2005年4-6月间常熟江段渔业群落进行研究,并对春禁前后相关指标进行对比分析。研究期内常熟江段共计出现渔业生物38种,分别隶属于11目17科33属;春禁后群落主要优势种为长春鳊、黄颡鱼和鲻,单位重量大于100g的种类占据优势。多样性特征值平均指标为:Margalef指数3.32,Wilhm改进指数2.50,Simpson指数0.18,Pielou指数0.76。对1999-2005年4-6月间安庆江段渔业群落进行研究,并对春禁前后相关指标进行对比分析。研究期内安庆江段共计出现渔业生物45种,分别隶属于8目14科38属。春禁后群落主要优势种为鲫、鲶和鲤,单位重量大于100g的种类占据优势。多样性特征值平均指标为:Margalef指数3.28,Wilhm改进指数2.45,Simpson指数0.16,Pielou指数0.79。结果表明实施长江春季禁渔后崇明江段渔业群落组成变化显著,复杂程度有所下降,多样性特征值仍大幅度波动,企稳回升趋势不明显;常熟和安庆江段渔业群落结构复杂程度大幅提升,物种多样性水平显著上升并趋于稳定。更多还原

【Abstract】 Studies on biodiversity status of fishery community in lower reaches of Yangtze River were carried out,and primary evaluations of the Spring Closed effect on fishery community in the sections of Chongming,Changshu and Anqing were also done.During 2004-2005,studies on fishery community in lower reaches of Yangtze River were carried out and a better understanding on its characteristics description and fishery yield calculation were reached.Besides that,comparisons of relative indexes among all the sampling stations were attained at the same time.In the community fishes of 14 oders,32 families,66 genera and in all 82 species,most of which were settled in fresh water,were occupied.Among them the one with its unit weight under 100g were more than others and the dominant species were Parabramis pekinensis,Carassius auratus and Coilia mystus. Indexes of biodiversity could be summarized as Margalef’s index 6.46,Shannon-Wiener’s 2.41,Simpson’s 0.14 and Pielou’s 0.55.Average yield per boat accounted for 5519.2kg.Studies on fishery community in Chongming section in the Spring Closed season during 1999-2005 were carried out,and contrast analysis of correlative indexes before and after the Spring Closed was also done.During the period,fishes,shrimps and crabs,which belong to 12 orders,22 families,33 genera and 37 species were collected.The dominant species were Coilia mystus,Collichthys lucidus and Stromateoides argenteus after the Spring Closed, while small species with its unit weight under 20g were remarkably more than others.Average index of biodiversity characters after the Spring Closed indicated that Margalef’s index 1.50,Wilhm’s 1.83,Simpson’s 0.24 and Pielou’s 0.72.Studies on fishery community in Changshu section in the Spring Closed season during 2000-2005 were carried out,and contrast analysis of correlative indexes before and after the Spring Closed was also done.In the period,fishes,shrimps and crabs,which belong to 11 orders,17 families,33 genera and 38 species were collected.The dominant species were Parabramis pekinensis,Pelteobaggrus fulvidraco and Mugil cephalus after the Spring Closed,and species that was more than 100g of its unit weight were remarkably more than others.Average index of biodiversity characters after the Spring Closed indicated that Margalef’s index 3.32,Wilhm’s 2.50,Simpson’s 0.18 and Pielou’s 0.76.Studies on fishery community in Anqing section in the Spring Closed season during 1999-2005 were carried out,and contrast analysis of correlative indexes before and after the Spring Closed was also done.In the period,fishes,shrimps and crabs,which belong to 8 orders,14 families,38 genera and 45 species were collected.The dominant species were Cyprinus carpio,Parasilurus asotus and Cyprinus carpio after the Spring Closed,and the species that was more than 100g of its unit weight were remarkably more than others. Average index of biodiversity characters after the Spring Closed indicated that Margalef’s index 3.28,Wilhm’s 2.45,Simpson’s 0.16 and Pielou’s 0.79.In all the results showed that in Chongming section the Spring Closed brought evident change to the community composition while the complexity got certain drop.Meanwhile Characters of biodiversity fluctuated in a wide range,and it indicated little uptrend sign towards stability.On the contrary notable advance of both fishery community complexity and biodiversity level in the sections of Changshu and Anqing could be found.更多还原