鄂西北六个自然保护区鱼类群落结构及多样性比较

为了解鄂西北地区的鱼类多样性和鱼类群落结构,于2007~2012年先后对鄂西的八卦山自然保护区、堵河源自然保护区、五道峡自然保护区、南河自然保护区、野人谷自然保护区及漳河源自然保护区的鱼类资源进行调查。结果显示,6个自然保护区共有鱼类79种,隶属4目15科51属。鲤形目鱼类为6个自然保护区的主要类群,共56种,占总数的70.89%。6个自然保护区的鱼类食性和生态类群相似,鱼类食性均以肉食性和杂食性为主,草食性鱼类较少;定居性鱼类占主体,河湖洄游性和喜流水性鱼类较少。渔获物分析表明,堵河源自然保护区鱼类丰富度指数(D)最大,为2.60,八卦山自然保护区鱼类丰富度指数最小,为0.91。多样性分析表明,同一水系的保护区之间的β_c值和β_R值均比处于不同水系的保护区之间的β_c值和β_R值小;处于同一水系的保护区相似性系数(C_j)较高,处于不同水系的保护区之间的相似性系数较低(C_j),这很好的诠释了处于同一水系的自然保护区在地理环境上的连续性,而处于不同水系的自然保护区之间出现了地理环境的分化隔离。目前水电开发和过度捕捞是该地区鱼类最大的威胁因子,建议强化渔政管理,并建立鱼类人工繁育基地,以减缓水电工程带来的不利影响,恢复天然渔业资源。

COMPARISON OF FISH COMMUNITY STRUCTURE AND BIODIVERSITY AMONG SIX NATURE RESERVES IN NORTHWEST HUBEI,CHINA

In order to understand the fish diversity and the community structure in Northwest Hubei,investigation was carried out in Baguashan,Duheyuan,Yerengu,Nanhe,Wudaoxia and Zhangheyuan nature reserves in Northwest Hubei from 2007 to 2012.We recorded 79 species,belonging to 4 orders,15 families and 51 genera.Among all the species,order Cypriniformes was the most dominant component(70.89％),with 56 species recorded.Feeding diets and ecological groups of fish were similar among the six nature reserves.Carnivorous and omnivorous fish were most abundant,and herbivorous fish were among the minority.Limnophilic fish was far more than diadromous and rheophilic species.The Margalef index (D) at Duheyuann natural reserve was the largest,with a value 2.60,whereas the lowest D was found at Baguashan natural reserve (0.91).The diversity index showed that the nature reserves in the same drainage system had a low βC index and βR index than those between different drainage systems.The index of similarity (Cj) was high between the natural reserves in the same drainage system and low between different drainage systems,explaining.well the fact that the nature reserves in the same drainage system has the continuity of the geographical environment while the nature reserves between different drainage systems existed the geographical isolation.The hydropower development and overfishing are the greatest threat to the region fish.It is suggested to strengthen the fishery management and establish artificial fish breeding sites,to reduce the negative effects of water-power engineering and restore natural fishery resources.