淮河干流大型底栖动物群落结构及水质生物学评价

2011年3月、6月、9月和12月对淮河干流大型底栖动物群落进行了取样调查,共采集到大型底栖动物4门41科94种。结果分析表明,淮河干流大型底栖动物群落结构具有一定的时空变化。在时间尺度上,生物密度呈极显著的季节性变化(p=0.002),其最大值332.5 ind./m2出现在6月,最小值96.6 ind./m2则出现在9月;生物量的变化趋势与生物密度不同步,其最大值155.8 g/m2出现在9月,最小值40.0 g/m2则出现在3月,且季节性差异不显著。冗余分析(RDA)结果表明,溶解氧、盐度、溶解性总固体、水温和底质类型是影响底栖动物群落结构的主要环境因子。Shannon-Wiener多样性指数的季节性变化不显著,Margalef丰富度指数的季节性差异极显著(p=0.000);自上游至下游,这2个指数的变化规律表现出高度的一致性,其水质评价结果表明淮河干流水质总体上处于中度污染的水平。

COMMUNITY STRUCTURE OF MACROZOOBENTHOS AND BIOLOGICAL EVALUATION OF WATER QUALITY IN THE MAINSTREAM OF HUAI RIVER

The macrozoobenthic community structures of the mainstream of Huai Rirer were investigated in March,June,September,and December 2011.A total of 94 macrozoobenthic species from 41 families were recorded.Results showed that there was a significant temporal variation in the macrozoobenthic density (p =0.002).The maximum mean population density (332.5 ind./m2) occurred in June while the minimum population density(96.6 ind./m2) appeared in September.And yet,the temporal variation trend of biomass was not consistent with that of population densities.The maximum mean biomass (155.8 g/m2) occurred in September while the minimum biomass(40.0 g/m2) appeared in March,and there were no obvious differences among seasons.The redundancy analysis (RDA) results showed that the dissolved oxygen,salinity,total dissolved solids,temperature,and sediment types were the main environmental factors that affect the macrozoobenthic community structure.The temporal variation of Shannon-Wiener diversity index was not significant,but the Margalef richness index was showed significant seasonal variations (p =0.000).Even so,the variation trends of the two indices were highly consistent from the upstream to the downstream.Overall,the water quality of the mainstream of Huai River was evaluated at the middle-level pollution.