太湖地区不同水生植被生境下环棱螺的生存状况研究(英文)

目的]研究太湖地区不同水生植被生境下环棱螺的生存状况,为该地区环境监测提供合适的评价指标。方法]在太湖虞望河西附近生态建设工程区的挺水植物区、沉水植物区和无植物裸底区3种水生植被生境中放养等密度的环棱螺,测定环棱螺在蓝藻爆发阶段和非蓝藻爆发阶段的存活率、超氧化物歧化酶活性、丙二醛含量和P450酶浓度,并分析所测指标与湖水氨氮含量的相关性。结果]在蓝藻爆发阶段,挺水植物区、沉水植物区和无植物裸底区环棱螺的存活率分别为0%、55.2%和89.3%,SOD活性表现为先降后升,MDA与SOD变化趋势相反,P450酶则不断下降;在非蓝藻爆发阶段,3种生境环棱螺的存活率分别为90.6%、98.8和99.5%,SOD活性先降后升,MDA则为先升后降,P450酶的变化没有规律。2个阶段中环棱螺SOD活性与湖水氨氮含量均显著负相关,MDA只在非蓝藻爆发期与氨氮含量显著正相关,P450酶与氨氮含量无显著相关关系,这表明用环棱螺评价水生植被对底栖动物的影响时,P450酶活性并不是合适的指标。结论]该研究结果表明太湖地区的环棱螺体内SOD活性可以作为评价生境的指标,MDA可作为非蓝藻爆发阶段检测氨氮含量的指示物,但P450酶不能作为该地区3种生境环境污染早期诊断与预警的指标。

Research on Survival Conditions of Bellamya sp.in Different Aquatic Vegetation Habitats in Taihu Area

Objective] The paper was to investigate the survival conditions of Bellamya sp.in different aquatic vegetation habitats in Taihu area,so as to provide suitable evaluation indexes for environmental monitoring in the area.Method] Equal density of Bellamya sp.was placed in 3 aquatic vegetation habitats(emerged plant area,submerged plant area and non-plant area) in ecological engineering construction area near the west of Wangyuhe in Taihu,the survival rate,SOD activity,MDA content and P450 enzyme activity of Bellamya sp.during outbreak and non-outbreak stage of cyanobacteria were determined,and the correlation between these indexes and ammonia nitrogen content of lake water was also analyzed.Result] During the outbreak stage of cyanobacteria,the survival rates of Bellamya sp.in emerged plant area,submerged plant area and non-plant area were 0%,55.2% and 89.3%,respectively,SOD activity first decreased and then increased,the change trend of MDA content was opposite with SOD change trend,P450 enzyme activity continuously decreased.During non-outbreak stage of cyanobacteria,the survival rates of Bellamya sp.in 3 habitats were 90.6%、98.8 and 99.5%,respectively,SOD activity first decreased and then increased,MDA content first increased and then decreased,the changes of P450 enzyme activity were not regular.SOD activity of Bellamya sp.during 2 phases had significantly negative correlation with ammonia nitrogen content of lake water,MDA content had significantly positive correlation with ammonia nitrogen content of lake water only during non-outbreak stage of cyanobacteria,P450 enzyme activity has no significant correlation with ammonia nitrogen content.This indicated that when Bellamya sp.was used to evaluate the impact of aquatic vegetation on benthic animals,P450 enzyme activity was not the suitable indicator.Conclusion] SOD activity in muscle tissue of Bellamya sp.could be used as the indicator for evaluation of habitat,MDA could be used as indicator for detection of ammonia nitrogen content during non-outbreak stage of cyanobacteria,P450 enzyme could not be used as the indicator for early diagnosis and early warning of environmental pollution in 3 habitats in Taihu area.