西湖通运河水道(古新河)冬季鱼类群落结构及多样性
Community Structure and Diversity of Fish in the Channel (Guxin River) Connecting the West Lake and the Beijing-Hangzhou Grand Canal in Winter

为了解古新河鱼类群落结构特征，于2022年12月对该河进行了1次调查，共采集鱼类13种，隶属于2目4科，其中76.92%为鲤科(Cyprinidae)鱼类。古新河水域鱼类群落优势种为蒙古鲌(Culter mongolicus)、银鲫(Carassius auratus gibelio)；4种摄食功能群中，杂食性(46.15%)和肉食性(38.46%)鱼类物种数比例较高，共占总物种数的84.62%；3种生态类群中，淡水定居性鱼类占绝大多数(84.62%)。群落Shannon-Wiener多样性指数值偏低，平均值为1.15，且在空间上有差异，1#的$H^{\prime }$ 为0.76，不到2#的1/2，引起原因应与蒙古鲌等优势种空间分布不均及采样点间物种数不同有关。
To understand the status of biodiversity and community structure of fish assemblage in the Guxin River, the resource survey was conducted in December 2022. A total of 13 species of fish were collected, belonging to 2 orders and 4 families. Among them, Cyprinidae had the largest number of species, accounting for 76.92%. Culter mongolicus and Carassius auratus gibelio were the dominant species in winter. Omnivorous (46.15%) and Carnivorous (38.46%) fish specices were the most frequent of the four feeding functional groups, which account for 84.62% of the total, and sedentary fish species (84.62%) were the most frequent of three ecological groups. The Shannon-Wiener diversity index of the community was relatively low, with an average value of 1.15. And there were spatial differences, with $H^{\prime }$ of 1# being 0.76, which was less than half of 2#. The reason for this should be related to the uneven spatial distribution of dominant species such as Mongolian culter and the different number of species between sampling points.