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研究选择长江中游西洞庭湖水系太湖新银鱼移植水体(黄石水库)和未移植水体(蒙泉水库),研究太湖新银鱼(Neosalanx taihuensis Chen)移植对浮游动物食性鱼类(Hemiculter leucisculus Basilewsky)早期生长和摄食的影响。2009年7月下旬和8月中旬共采集稚鱼157尾,其中7月下旬采集稚鱼在14—23日龄之间,两水体间生长差异不显著;8月中旬采集稚鱼在20—49日龄之间,黄石水库生长率显著小于蒙泉水库。对样品耳石日轮分析发现25日龄之前两水体稚鱼生长率相似,之后黄石水库稚鱼较蒙泉水库生长慢。食性分析发现25日龄前两水体稚鱼食物组成相似,主要摄食轮虫、小型枝角类和桡足类;25日龄后黄石水库稚鱼食性没有显著变化,而蒙泉水库稚鱼则转食大型枝角类、昆虫及鱼卵和仔鱼。两水体气候条件、营养状况、鱼类区系组成上基本相同,是否有太湖新银鱼移植是两水体间的主要差别。太湖新银鱼春群在1—5月间繁殖,而的繁殖在6月下旬之后。因此在早期生活史阶段与太湖新银鱼的食物竞争会主要发生在转食大型浮游动物之后。太湖新银鱼摄食使黄石水库大型浮游动物饵料资源短缺,稚鱼在25日龄后不能转食,是导致黄石水库幼鱼在25日龄后生长减慢的重要因素。
In order to study the effect of Neosalanx taihuensis Chen on the mortality of Hemiculter leucisculus Basilewsky (Phytoplankton) from the West Lake Dongting Lake in the Yangtze River, Effects of early growth and feeding. In late July and mid-August 2009, 157 juveniles were collected, of which juveniles were collected in late July and aged 14-23 days respectively. There was no significant difference in growth between the two water bodies. In mid-August, juveniles were collected at 20 Between 49 days of age, the growth rate of Huangshi Reservoir was significantly less than that of Mengquan Reservoir. The day of otolith analysis showed that the growth rates of juveniles in two water bodies before 25 days of age were similar, and then the juveniles in Huangshi Reservoir grew slower than those in Mengquan Reservoir. Feeding habits analysis showed that juveniles fed on 25-day-old had similar food composition, mainly feeding on rotifers, small-sized cladocerans and copepods. After 25 days of age, juvenile feeding habits of Huangshi Reservoir did not change significantly, while juvenile of Mengquan Reservoir turned Large branches, insects and fish eggs and larvae. Two water body climate conditions, nutritional status, fish fauna composition is basically the same, whether the Taihu Lake silverfish transplantation is the main difference between the two bodies of water. The Taihu Lake new silverfish spring population in January-May breeding, and the breeding of in late June after. Therefore, the competition for foodstuffs with the fresh silverbait of Taihu Lake at the stage of early life history mainly occurs after the feeding of large zooplankton. The feeding of Taihu Lake fresh silverfishes resulted in a shortage of feed resources for large zooplankton in Huangshi Reservoir. The larvae could not feed after 25 days of age, which is an important factor that led to the slow growth of young Yellowstone after 25 days of age.