赣江下游一级支流鱼类多样性比较分析

分析锦江、袁河鱼类群落结构与种类多样性的时空动态特征,以期为鱼类资源的管理与保护提供科学依据,并为深入研究赣江流域的鱼类多样性及梯级枢纽运行的生态调度奠定基础。2014年3月-2015年2月,按季节对锦江的高安、上高江段和袁河的宜春、新余江段渔获物进行调查,调查渔具以刺网(网目规格分别为200、120、80、40和20 mm)和电拖网为主。调查期间共采集鱼类3目11科47属67种,种类以鲤科为主,占68.66%。锦江3目7科36属51种,袁河3目10科32属36种;银鲴、鲫、银鮈、蛇鮈为锦江的优势种,银鮈、彩石鳑鲏、鲫、棒花鱼为袁河的优势种;鱼类群落的Margalef丰富度指数、Shannon-wiener多样性指数、Pielou均匀度指数均表现为锦江略高于袁河;丰度生物量比较曲线显示,锦江的鱼类群落结构处于中度干扰状态,而袁河的处于严重干扰状态。锦江和袁河的鱼类群落与种类多样性存在一定的差异。

Comparative Analysis of Fish Community Diversity in Two Primary Tributaries of the Lower Ganjiang River

Ganjiang River, the largest river in the Poyang Lake system, plays an important role in maintaining the fish diversity and ecological integrity of Poyang Lake. The aquatic ecosystem and fish community in the Ganjiang River basin face severe challenges due to excessive fishing, water pollution, gold mining and construction of a water conservancy project. The spatial-temporal dynamics of the fishery and species diversity in the Jinjiang and Yuanhe Rivers were investigated to better understand the status of fish resources in two first-level tributaries of the lower Ganjiang River and lay a foundation for further study of fish community diversity in the Ganjiang River basin. Seasonal surveys were carried out from March 2014 to February 2015 in the Gaoan and Shanggao sections of Jinjiang River and the Yichun and Xinyu sections of Yuanhe River using gill nets (mesh sizes of 200, 120, 80, 40 and 20mm) and electric trawls. A total of 67 species, belonging to 3 orders, 11 families and 47 genera were collected during the investigation. Cyprinids were the dominant, accounting for 68.66% of the total species. In comparing the fish communities and species diversity in the Jinjiang River and Yuanhe rivers, four differences were observed. (1) In Jinjiang River, 51 species from 3 orders, 7 families and 36 genera were collected and in Yuanhe River, 36 species from 3 orders, 10 families and 32 genera were collected. (2) In Jinjiang River, the dominant species were Xenocypris macrolepis, Carassius auratus, Squalidus argentatus and Saurogobio dabryi and in Yuanhe River, the dominant species were Squalidus argentatus, Rhodeus lighti, Carassius auratus and Abbottina rivularis. (3) The Margalef abundance index (D), Shannon-wiener diversity index (H'') and Pielou evenness index (J'') in Jinjiang River were, respectively, 7.67, 3.11 and 0.79, slightly higher than in the Yuanhe River, where the respective values were 7.11, 2.53 and 0.70. (4) Analysis of the abundance-biomass comparison curves (ABC) indicates that the fish community structure is moderately disturbed in the Jinjiang River and seriously disturbed in the Yuanhe River.