生态修复后海三棱藨草湿地底栖生物多样性的年度变化及影响因子

如何确定湿地生态修复过程中底栖生物群落结构的变化及其影响因子对湿地生态系统操纵及生态修复效果有重要意义。研究以南汇东滩海三棱藨草湿地为对象,研究底栖生物群落结构的年度季节变化及空间格局。共鉴定大型底栖动物30种,四季都存在的优势种有光滑狭口螺、拟沼螺、堇拟沼螺和中国绿螂。春季以中国绿螂为主要物种,优势度大于0.4;夏季以拟沼螺和堇拟沼螺为主,优势度分别大于0.1和0.2;秋冬季优势种数目比春夏季高,均为13种,但优势种值较春夏季为低,且均匀。多样性、丰富度指数(p0.01)及均一性指数(p0.05)在空间上均具有显著性差异,其中多样性指数最高到达2.53。根据近岸海域环境监测规范(HJ442-2008),南汇东滩湿地生境质量从极差、差改善成等级一般,生境质量提高明显。底栖生物群落结构影响因素的排序分析表明,春夏秋三季大型底栖动物群落结构特征与植被指数及高程相关,其次是有机碳、含水率、导电率和硝氮,而冬季大型底栖动物群落结构特征受含水率、导电率和硝氮的影响最大。

Variation and the Associated Affecting Factors of Benthic Biodiversity in Wetlands of Scirpus Mariqueter on Remediated Nanhui Coasts#br#

Abstract：How the structure and the associated impacting factors of benthic organisms responding to ecological remediation project is a promising work of ecosystem manipulation for wetlands remediation. The annual temporal and spatial patterns of benthic community structure were studied in Scirpus mariqueter wetland on remediated Nanhui Coasts. A total of 30 species of macro benthos were identified in the study. The dominant species appeared in the whole four seasons are Stenothyra glabra, Assiminea, Assimineaviolacea, and Glauconomechinensis Gray. In spring, Glauconomechinensis Gray is the dominant species, and the dominance value is bigger than 0.4. In summer, Assimineasp and Assimineaviolacea Heude are the dominant species with the dominance value bigger 0.1 and 0.2 respectively. By a number of 13 in autumn and winter the dominant species number is higher than that in spring and summer but the dominance value is lower than that in spring and summer, and distributes spatial evenly. There is significant spatial difference for the indices of Shannon-Weiner Index (H’）, species richness (p<0.01) and Pilou’s evenness index (p<0.05), with a highest H’ value of 2.53. According to the Specification for Offshore Environmental Monitoring (HJ442-2008) the habitat quality of Nanhui Coasts are upgraded from very poor and poor levels to general. The canonical correlation analysis (CCA) showed that in spring, summer and autumn the benthic organisms are significantly correlated with vegetation index and elevation, followed by organic carbon and water content, conductivity, and NO-3,while in winter the affecting factor is water content, electrical conductivity and NO-3.