枸杞岛瓦氏马尾藻藻场生态系统健康评价

Assessment of Sargassum vachellianum bed ecosystem health in Gouqi Island

采用指标体系法,对枸杞岛瓦氏马尾藻藻场生态系统健康状况进行研究。从藻场生态系统压力、藻场水质状态、藻场生物群落结构和藻场生态系统功能4个方面选取18个指标构建评价体系,并利用层次分析法(AHP)确定各指标权重值,建立海藻场生态系统健康评价多指标综合指数模型。研究结果表明,枸杞岛瓦氏马尾藻藻场生态系统综合评价指数为0.58,属中度退化、Ⅲ类退化级别,藻场附近海域营养状态质量指数值为5.47,富营养化压力对该藻场生态系统健康状况影响最大。本研究同时还对藻场退化原因做了分析,为该藻场修复方法的选择和修复目标奠定了基础。

Assessment of ecosystem health of seaweed bed is important reference for the choice of restoration methods.In this paper,we assessed the health of Sargassum vachellianum bed ecosystem in Gouqi Island by the assessment index system method.The assessment index system consisted of 18 assessment indicators belonging to 4 aspects,i.e.the pressure of ecosystem,the status of water quality,the structure of biological community and the function of ecosystem.The weight of indicators were determined by Analytic Hierarchy Process（AHP）.Then a model of multi-indicators comprehensive index for assessment ecosystem health of seaweed bed was build.The results showed that：the comprehensive index of S.vachellianum bed ecosystem in Gouqi Island was 0.58,indicating moderate degradation and class III degradation level.The nutrient quality index was 5.47 around the seaweed bed.Eutrophication pressure had a great effect on the health of the seaweed bed ecosystem.Meanwhile,we analyzed the causes of the seaweed bed＇s degradation which was necessary to choose the proper of restoration method and forecast the result of the restoration.