三峡水库不同水位时期大宁河底栖动物群落结构

Macroinvertebrate community structure of Daning River in different water-level periods of the Three Gorges Reservoir

为研究不同水位时期大宁河底栖动物群落的结构特征及其差异,于2011-2013年间分别在三峡水库低水位期(145 m)和高水位期(170 m)对大宁河的底栖动物进行定性和定量调查。低水位期生物密度和生物量分别为(80.32±32.14)ind./m2和(1.44±0.45)g/m2,高水位期生物密度和生物量分别为(133.82±46.94)ind./m2和(1.53±0.51)g/m2。寡毛类在静水区域占优势,水生昆虫在流水区域占优势。底栖动物物种组成和分布表现为高水位期高于低水位期,流水区域显著高于静水区;不同水位时期生物密度和生物量差异显著,优势种及其相对丰度有较大波动;生物多样性表现为高水位期高于低水位期,流水区域显著高于静水区。聚类分析和多维尺度分析结果显示,大宁河底栖动物群落结构在时间上和空间上均出现了明显的分化。

To illustrate the characteristics and differences of macroinvertebrate community of Daning River , qualitative and quantitative surveys were conducted on macroinvertebrate at low water -level period （145 m） and high water-level period （170 m） of the Three Gorges Reservoir from 2011 to 2013.During low water-level period, the macrozoobenthos density and biomass were （80.32 ±32.14） ind./m^2 and （1.44 ±0.45） g/m^2 respectively, while the density and biomass were （133.82 ±46.94 ） ind./m^2 and （1.53 ±0.51 ） g/m^2 during high water-level period.Tubificidae dominated the lentic zones, and aquatic insects dominated the lotic zones .Macroinvertebrate species composition and distribution in high water-level periods was higher than that in low water -level period , and it was significantly different between the lotic water area and the static water area.During the different water -level period, the density and biomass were significantly different from each other , and the dominant species and their relatively abundance showed great difference .The biodiversity in high water-level period was higher than that in low -water period , the lotic water area was significantly higher than the static water area.Multidimensional Scaling （ MDS） analysis and cluster analysis showed that macroinvertebrate community structure had been obviously differentiated in both spatial and temporal scale .