基于优化的地球生命力指数分析鄱阳湖鸟类多样性变化

Analysis of Bird Diversity Variation in Poyang Lake Based on Optimized Living Planet Index

对地球生命力指数(LPI)进行探索和改进,以便在小尺度下分析生物多样性指数变化。采用信息熵和对数优化LPI指数,形成新指数1(LPIN1)和新指数2(LPIN2)。结合自举法(bootstrap)和Wilcoxon符号秩检验,对优化后的指数设置95%的置信区间,并比较指数间年际差异。基于2011—2017年鄱阳湖地区鸟类观测数据,比较常规生物多样性指数、LPI指数以及优化后的LPIN1和LPIN2指数。结果表明鄱阳湖地区鸟类LPIN1和LPIN2指数均上升5%,生态系统呈健康水平。2011—2017年鄱阳湖地区鸟类LPI指数上升53%,超过鸟类多样性指数合理变化区间。常规生物多样性指数Shannon-Wiener多样性指数和Simpson多样性指数表明不同年际间生物多样性处于稳定状态,但不能体现指数的变化幅度。优化后的2个新指数对于小尺度下指数变化趋势表现得更加合理,能够反映特定区域生态系统水平的健康程度。

The study focuses on the optimization of living planet index(LPI)to analyze the variation of biodiversity in fine scale.Comentropy and logarithm were utilized to generate these new indexes(LPIN1 and LPIN2).Using bootstrap method with Wilcoxon symbol rank test and 95%confidence interval,these optimized indexes were compared among different years.Based on the data on continuous bird monitoring in Poyang Lake from 2011 to 2017,the diversity of bird community was obtained by conventional method,LPI,LPIN1 and LPIN2.Results demonstrate that the two optimized indexes rose by 5%and ecosystem in Poyang Lake was stable.Besides,LPI index rose by 53%,which is not within the reasonable variation range of diversity index in Poyang Lake.Shannon-Wiener index and Simpson index indicate that the biodiversity was stable among different years,but failed to reflect the variation of the index.In contrast,two optimized new indexes can better delineate the variation trend of biodiversity in a fine scale and reflect the health of ecosystems in the Poyang Lake.