改性当地土壤技术修复富营养化水体综合效果研究:Ⅱ.底栖动物群落结构和多样性的响应

摘要

从2010年10月开始在太湖梅梁湾围隔内实验区实施了改性当地土壤技术,在研究其对水体富营养化和蓝藻水华长效控制作用的同时,重点研究了底栖动物群落对此技术的响应.研究发现:经过11个月的处理,相比对照区,实验区内软体动物的平均密度和生物量分别增长了124％和33.8％,底栖动物Margalef和Shannon-Wiener多样性指数分别增长了41.1％和18.5％.环境因子和底栖动物群落的典范对应分析发现叶绿素a、温度、溶解氧和总磷对底栖动物群落有显著影响.本研究表明通过改性当地土壤技术降低水体营养盐含量和叶绿素a含量、增加底泥表层溶解氧含量,可以在一定程度上改善底栖动物生境,提高其物种多样性.%Field pilot tests of modified local soil/sand induced ecological restoration technology ( MLS-IER) were carried out in the experimental enclosure of Meiliang Bay of Lake Taihu. The response of zoobenthos community in the experimental areas was evaluated based on the results of the survey from November 2010 to September 2011. The results revealed that the average density and bi-omass of mollusca in the experimental area were improved by 124% and 33. 8% , respectively, and the average Shannon-Wiener index and Margalef index of zoobenthos were improved by 41. 1% andl8.5% , respectively, compared to the control area. Canonical correspondence analysis was employed to identify the relationship between environmental factors and zoobenthos community. Chlorophyll-a, temperature, dissolved oxygen and total phosphorus concentration were found to be significant factors that influenced the zoobenthos community. This study indicated that the habitat and species diversity of the zoobenthos can be improved by the reduction of Cyano-HABs and nutrient levels, and the increase in dissolved oxygen due to the MLS-IER treatment in the enclosure.