黄河三角洲芦苇湿地底栖无脊椎动物与环境因子的关系研究——以石油开采区与淡水补给区为例

分别于2018年5月和8月对黄河三角洲芦苇湿地19(淡水补给区11处,石油开采区8处)处采样点的底栖无脊椎动物和水体理化指标进行调查采样,运用统计方法分析两个区域物种组成、优势种、多样性、群落结构以及与环境因子的关系。结果表明:两季共采集到底栖无脊椎动物54种,主要以水生昆虫、腹足纲和软甲纲为主,淡水补给区和石油开采区各类群组成差异明显。独立样本T检验表明淡水补给区和石油开采区水体理化指标间差异显著(P0.05)。双因子方差分析显示,昆虫纲和腹足纲密度在两区域差异显著(P0.05),软甲纲和腹足纲密度在季节上差异明显(P0.05)。底栖无脊椎动物优势种共10种,淡水补给区指示物种8种,而石油开采区未发现有指示物种。聚类和非参数多维排序(nM DS)显示,底栖无脊椎动物群落结构相似性较低; RDA结果表明:淡水补给区底栖无脊椎动物群落结构主要受Cond,TDS,Sal,pH,Eh,HCO_3~-,SO_4~(2-)等环境因子的影响。石油开采区底栖无脊椎动物群落结构影响较大的环境因子为HCO_3~-、NH_4-N。

Composition of benthic invertebrate communities in reed (Phragmites australis) wetlands of the Yellow River Delta: Comparisons between oil exploitation and freshwater recharge areas

The benthic invertebrates and environmental factors were sampled and analyzed in May and August, 2018 from 19 sites of reed wetlands (11 freshwater recharge areas and 8 oil exploitation areas) in the Yellow River Delta. Multivariate analysis methods were used to analyze the composition, dominant species, biodiversity, community of benthic invertebrate assemblages, as well as their relationships to the environmental factors. The results showed that 54 taxa collected by two samplings were mainly composed by Aquatic Insect, Gastropoda and Mollusca. There are obvious differences in composition of benthic invertebrates between freshwater recharge and oil exploitation area. Independent-Samples T Test showed that freshwater recharge area and oil exploitation area were significant different in environmental factors (P<0.05). Two-way ANOVA analysis showed that there were significant differences in insect and Gastropoda density between the two regions (P<0.05). The seasonal variations of Mollusca density and Gastropoda density were both significant (P<0.05). Ten species of benthic invertebrates were dominant in the study area. Eight species of benthic invertebrate were tested to be the indicator species in freshwater recharge area, but no indicator species were found in oil exploitation area. Cluster and nMDS analysis indicated the low similarity of the benthic invertebrate community between the freshwater recharge area and oil exploitation area. The RDA results showed that the community structure of benthic invertebrates in freshwater recharge area was mainly affected by Cond, TDS, Sal, pH, Eh, HCO₃^-, SO₄^2- and the influential environmental factor in oil exploitation areas were HCO₃^-and NH₄-N.