日本沼虾与秀丽白虾的营养生态位  

Studies on Trophic Niches of Macrobrachium nipponensis and Exopalaemon modestus

作　　者：张欢[1,2] 谢平[1,2] 吴功果[2] 张欢[2] 张培育[2] 徐军 

机构地区：[1]华中农业大学水产学院,湖北武汉430070 [2]中国科学院水生生物研究所,东湖湖泊生态系统试验站,湖北武汉430072

出　　处：《环境科学研究》2013年第1期22-26,共5页Research of Environmental Sciences

基　　金：国家自然科学基金项目(31170439);国家重点基础研究发展(973)计划项目(2012CB417004)

摘　　要：为科学评估虾类的营养关系及资源的保护,利用稳定同位素技术研究了2种淡水虾类在大型通江湖泊——洞庭湖和鄱阳湖中的营养生态位和生态宽幅大小.结果表明,日本沼虾与秀丽白虾的δ13C值呈显著差异,而δ15N值无明显差异.同时,由于营养状况及水文的差异,虾类同位素值的差异在2个湖泊中表现不同.日本沼虾的δ13C值范围比秀丽白虾大,频率分布相对集中在-25.0‰～-23.0‰区间,表明其摄食的食物来源更广,对某些饵料生物有所偏好.另外,日本沼虾与秀丽白虾的营养生态位重叠程度较大,表明二者的主要食物来源相同,在食物网中占据的营养级相近,存在着激烈的种间竞争.在鄱阳湖中,日本沼虾占有的营养生态位和生态宽幅大于秀丽白虾;而在洞庭湖的研究结果则相反,主要是由于采样区域生境的差异及人类活动干扰的程度不同所致.This study was undertaken to assess the trophic niches and niche widths between two freshwater shrimps, Macrobrachium nipponensis and Exopalaemon modestus, from the Yangtze River-connected lakes - Dongting lake and Poyang lake - using stable carbon and nitrogen isotope analysis. The overall aim was to provide the information valuable for evaluation of trophic relationships and for protection of natural resources. Results showed significant differences in δ13C values between M. nipponensis and E. modestus, but no difference in δ15N values between two species. Meanwhile, differences in isotopic variations of shrimps were found between lakes which had differences in nutrient level and in hydrology. The range of δ13C signatures in M. nipponensis was greater than those of E. mode^tus and mainly distributed from - 25.0‰ to - 23.0‰, indicating that M. nipponensis fed on more food sources but preferred a certain one. There was a large overlap of trophic niches between the two species. This result indicated that food consumed were nearly the same tbr both species, implying similar trophic positions and strong inter-composition. In the Poyang Lake, M. nipponensis had a trophic niche and niche width larger than E. modestus. However, there were opposite observations in the Dongting Lake due to variations of sampling habitats and the degree of human disturbances.

关 键 词：日本沼虾 秀丽白虾 稳定同位素 营养生态位 生态宽幅 

分 类 号：Q958.12[生物学—动物学]