赣江流域淡水生态系统完整性与健康状态的鱼类F-IBI值评价

ASSESSMENT ON FRESHWATER ECOSYSTEM INTEGRITY AND HEALTH IN GANGJIANG RIVER BASIN THROUGH THE FISH IBI METHOD

河流生态系统是地球上最为复杂的生态系统之一,它触及到自然环境所有部分,且几乎与各方面的人类活动均存在直接或间接的联系。河流生态学中最具活力的领域之一就是生态系统健康研究。鱼类是最早建立的生物完整性和健康评价的生物类群,一直以来被广为应用。在调查赣江流域17条一级支流和干流的不同江段的鱼类资源之后,首次通过鱼类完整性指数(F-IBI)来评价赣江流域生态系统的健康状态。研究结果表明:赣江流域近70%调查样点鱼类群落完整性处于一般的状态,25%调查样点处于较好状态,5%调查样点则处于差的状态;赣江水系各河流的鱼类群落完整性均处于差-一般的水平。总之,流域支干流的水生态系统健康处于差-一般的状态。认为鱼类完整性受损与人工筑坝和蓄水等人类活动密不可分。建议开展系列补救措施,如增加鱼道或鱼梯等。

River ecosystem is one of the most complex ecosystems in the world,being involved in each part in the natural environment,and almost being directly or indirectly linked with every aspect of human activities.Ecosystem health assessment is one of the most active fields in river ecology.Fish was first used to construct a biotic integrity and health assessment and now is a widely applied biota group.This paper first assesses the health status of river ecosystem in Gangjiang River Basin through fish index of biotic integrity（F-IBI） after investigating the stock of fish among 17 tributaries and different river zones of main stream.Results show F-IBI scores of about 70% of sampling sites are in the fair status,25% in good and 5% in poor.F-IBI scores of tributaries and main stream in Ganjiang River system are in the poor to fair status.In a word,river ecosystem health of Ganjiang River Basin is at the level of the poor to fair.It is considered that the declined fish integrity of Ganjiang River Basin is related with human activities such as river damming and impoundment.We suggest that the restoration measurements such as addition of fish way or fish ladder should be employed.