论文部分内容阅读
根据2004年8月、11月和2005年2月(Ⅰ年度)、2005年8月、11月和2006年2月、5月(Ⅱ年度)、2007年8月、11月和2008年2月和5月(Ⅲ年度)对长江口中华鲟自然保护区15个站位点的底拖网调查数据,对该水域的底层鱼类群落结构特征及时间和空间变化规律进行了分析。结果表明,调查中捕获底层鱼类42种,隶属于13目24科39属。底层鱼类的种类组成和群落结构进行聚类分析,15个站位聚合成两大类群,类群A位于南支北港和北港北沙近东滩水域,共出现20种底层鱼类,主要以淡水性和河口性鱼类为主;类群B位于北支和北港北沙近外海水域,共出现鱼类39种,主要以河口性和海洋性鱼类为主。ANOSIM和SIMPER分析表明底层鱼类群落结构不同季节间差异显著,造成这种趋势的主要原因可能是与棘头梅童鱼(Collichthys lucidus)和凤鲚(Coilia mystus)的繁殖和索饵洄游有关。
According to August 2004, November and February 2005 (Year I), August, November 2005 and February 2006, May 2006 (Year II), August 2007, November 2007 and February 2008 And May (Ⅲ) on the bottom trawl survey data of 15 stations in the Yangtze River Estuarine Sturgeon Nature Reserve. The characteristics of the fish community structure and the temporal and spatial variation of the fish community were also analyzed. The results showed that 42 species of bottom fish were captured in the survey, belonging to 13 orders, 24 families and 39 genera. Cluster analysis of the species composition and community structure of the bottom fish showed that 15 stations aggregated into two groups. Group A was located in the North Dongbei Beach in Nanzibei and near Dongtan waters in Beisha, North China. Twenty species of bottom fish appeared, mainly in freshwater And estuarine fish. Group B was found in the near-offshore waters of the North Branch and Bei-Gang Beihai, with a total of 39 species of fish, mainly of estuarine and marine fish. ANOSIM and SIMPER analysis showed that the bottom fish community structure differed significantly among different seasons. The main reason for this trend may be related to the breeding and feeding migration of Collichthys lucidus and Coilia mystus.