香溪河水系大型底栖动物功能摄食类群生态学

The functional feeding group ecology of macroinvertebrate in Xiangxi River system

2004年7月至2007年6月,通过大型底栖无脊椎动物的量化监测,对三峡水库湖北库区最大河流香溪河大型底栖无脊椎动物功能摄食类群生态学进行研究。结果表明:香溪河大型底栖动物以收集者占绝对优势,其次为刮食者,捕食者、滤食者、撕食者相对丰度较小;各功能摄食类群分布明显受时空资源位的限制;香溪河物质循环能力、两岸物质的输入量和粗有机颗粒/细有机颗粒在九冲河明显高于其它河流,在冬季高于其它季节;物质输送能力以高岚河最高,在时间方面以冬季明显高于其它季节。逐步回归分析表明,流速、电导、浊度、总氮、二氧化硅对香溪河河流生态系统物质循环具有指示作用;二氧化硅和化学需氧量对物质输送能力具有指示作用;水温、水深、二氧化硅、总磷可作为沿岸物质输入量的指标;水温、二氧化硅可作为评估河道中粗、细有机颗粒比例的重要指标。

Based on quantitative investigation from July 2004 to June 2007 in Xiangxi River,the largest tributary in Hubei portion of Three-Gorge Reservoir,macroinvertebrate functional feeding groups were studied;some indices based on FFGs were used to evaluate river ecosystem.The results showed that gather-collectors were the main component in Xiangxi River system,followed by scrapers,and predators,filter-collectors,shredders only accounted for a small part.Every FFGs distribution was significantly different among seasons and tributaries in Xiangxi River.By analyzing the spatio-temporal distribution of some indices based on FFGs,the results showed that material cycling capability,lateral input capability,CPOM input/ FPOM input in Jiuchong River were much better than the other rivers,and they were much better in winter than in other seasons.Longitudinal transport capability was best in Gaolan River;and it was also better in winter.Stepwise regression analysis showed that material cycling could bemirrored by water velocity,conductivity,turbidity,total nitrogen,SiO2;Longitudinal transport could be mirrored by SiO2 and chemical oxygen demand（COD）;Lateral input capability could be mirrored by water temperature,water depth,SiO2,total phosphorus;and CPOM input/FPOM input was maily mirrored by water temperature and SiO2.