黄河故道尾闾湿地大型底栖动物群落对生态补水的响应研究

选取黄河故道尾闾湿地为研究区域，为了探寻以沉积物盐度表征生态补水工程对湿地生态环境的影响，同时以大型底栖动物群落组成、丰度、生物量表征生态补水工程对大型底栖动物群落的影响，分别于2014-2016年生态补水前（4-5月）、后（9-10月）采集生态补水恢复湿地及潮间带湿地沉积物和大型底栖动物样品。研究发现，在生态补水前，研究区域I-IV（陆-海方向）的沉积物盐度呈现先升高后降低的现象，而生态补水工程的实施显著降低了区域III的高盐度带特征；生态补水后沉积物盐度则呈现由陆向海逐渐升高的趋势。生态补水恢复区的大型底栖动物群落多以昆虫纲和甲壳纲为主，群落结构相比潮间带湿地的大型底栖动物较为单一。生态补水前，沉积物盐度与大型底栖动物丰度呈现“U”型关系，而与大型底栖动物生物量则呈现出倒“U”型关系；生态补水后，大型底栖动物丰度呈现出随沉积物盐度的升高而逐渐降低的态势，与此相反，大型底栖动物生物量则呈现出随沉积物盐度而逐渐增高的趋势。尾闾型湿地大型底栖动物群落动态演变规律研究对于滨海河口湿地生态补水工程的实施具有重要价值和科学意义。 

Ecological responses of macrobenthic community to freshwater replenishment in the tail wetland of old Yellow River

Sediment and macrobenthos samples were collected from the tail wetland of old Yellow River before (April-May)and after (September-October)freshwater replenishment from 2014 to 2016.Sediment salinity was used to represent effect of freshwater replenishment on habitat environment, composition, abundance and biomass of macrobenthic community was used to represent effect of freshwater replenishment on macrobenthic community.It was found that sediment salinity in areas Ⅰ-Ⅳ (from land to sea)increased firstly and then decreased.A high sediment salinity zone in area Ⅲ was identified before freshwater replenishment. Implementation of freshwater significantly reduced high sediment salinity in area Ⅲ, sediment salinity increased from land to sea in areas Ⅰ-Ⅳ.Composition of macrobenthic community in freshwater replenishment area,dominated by class of Insecta and Crustacea,was found to be relatively simple compared with intertidal wetland (area VI).The relationship between sediment salinity and macrobenthos abundance showed a "U"shape before freshwater replenishment,while sediment salinity had an inverted"U"relation with macrobenthos biomass.After freshwater replenishment,abundance of macrobenthos decreased slightly with the increase of sediment salinity,in contrast,biomass of macrobenthos increased gradually with salinity of sediment.Analysis of macrobenthic response to freshwater replenishment proj ect is of great significance to guide ecological restoration in estuary wetland.