黄山陈村水库河源溪流鱼类群落的食性

基于2010年11月在黄山陈村水库河源溪流中所采集的鱼类标本,对其中9种优势鱼类的食性特征进行了研究。结果表明:宽鳍鱲(Zacco platypus)、光唇鱼(Acrossocheilus fasciatus)和麦穗鱼(Pseudorasbora parva)等9种鱼类都以有机碎屑、藻类和无脊椎动物为主要食物,属典型的杂食性或无脊椎动物食性鱼类;食物组成的相似性分析结果表明,不同物种间的食物组成差异显著但存在部分重叠(P<0.001)。不同物种间的食物多样性和食性宽度也存在显著性差异(P<0.05),其中底栖型鱼类具有相对较高的饵料来源,而鱼类的食物多样性可能与其小生境选择性有关。根据食物重叠指数,9种优势鱼类之间存在明显的食物重叠(D>0.3),尤其是宽鳍鱲、光唇鱼、麦穗鱼、高体鰟鮍(Rhodeus ocellatus)和稀有花鳅(Cobitis sinensis)间的食物重叠指数超过0.9。陈村水库河源溪流的鱼类群落所表现出的食物组成、食物多样性、食性宽度和种间食物重叠性等特征,可能与其生态系统所具有的营养外源性和物理栖息地周期动荡性等密切相关。

Feeding habits of fish assemblage in headwater streams of Chencun Reservoir in Huangshan Mountain

Fish samples were collected from the headwater streams of the Chencun Reservoir in Huangshan Mountain in November 2010, with the feeding habits of nine dominant fish species examined. These fishes mainly fed on organic detritus, alga, and invertebrates, suggesting that they were omnivorous or invertivores. One-way ANOSIM indicated that the diet composition varied significantly with fish species, but existed part overlap (P<0.001). The diet diversity and food niche breadth also varied significantly with fish species (P<0.05). Generally, benthic fishes could feed on more diverse diet sources than non-benthic ones, suggesting the possible correlation between fish diet diversity and microhabitat preference. According to the index of diet overlap, there was an obvious diet overlap (D>0.3) among the nine dominant fishes, and especially for Zacco platypus, Acrossocheilus fasciatus, Pseudorasbora parva, Rhodeus bitterling, and Cobitis rarus, their diet overlap index was D>0.9. The above-mentioned diet characteristics of the fishes could have close relations with the exogenous food supply and unstable physical habitat of the headwater streams.