赤水河赤水段鱼类早期资源调查研究

赤水河是长江上游右岸一级支流，是长江上游珍稀特有鱼类国家级自然保护区的重要组成部分。为了解赤水河鱼类的繁殖情况，为保护区鱼类的相关研究和保护工作提供本底资料，于2007和2008年3~7月在赤水河赤水市江段进行了鱼类早期资源的调查工作。结果显示：至少有34种（亚种）鱼类在赤水市江段繁殖，其中包括长江上游特有鱼类4种，产漂流性卵的鱼类8种。鱼类繁殖期从3月持续到7月，盛期为5~7月。两年调查期间，分别经历了7次和5次繁殖高峰；在4~7月，漂流性鲫的资源量分别为3.26×108粒和5.26×108粒。复兴、丙安和太平3个江段为产漂流性卵鱼类的主要产卵场。鱼类繁殖盛期的水温范围为21℃~245℃，流量的增加可以促进产漂流性卵鱼类的繁殖。

FISH RESOURCES OF EARLY LIFE IN CHISHUI SECTION OF THE CHISHUI RIVER

The Chishui River,a first order right tributary of the upstream of the Yangtze River,is an important part of the national nature reserve for rare and endemic fishes in the upper Yangtze River basin.A survey on fish resources of early life was carried out in Chishui City located in the middle reaches of the Chishui River from March to July in 2007 and 2008.The results showed that there were at least 34 species spawned in Chishui section from March to July，which included eight species with pelagic eggs and four endemic species of the upper Yangtze River.In 2007 and 2008,the density of ichthyoplankton reached their peak for seven and five times,respectively.From April to July,the quantities of pelagic eggs were estimated to be 326×108 ind.and 526×108 ind. in 2007 and 2008,respectively.Three important spawning sites of fishes in the middle reaches of the Chishui River located in the towns of Bing’an,Fuxing and Taiping.The appropriate water temperature for fish reproduction varied from 21℃ to 24.5℃.The ichthyoplankton resource with pelagic eggs was promoted by increased water discharge.〖