湿地生态系统地球化学调查尺度研究

Study on the Scale of Geochemical Survey of Wetland Ecosystems

本文采用地质统计学、空间自相关分析等方法,对桃花江水库及其汇水范围进行湿地生态系统地球化学调查尺度研究,共采集表层沉积物样品110件,研究表层沉积物环境质量关键评价因子Cd、Hg、As、Pb、Cr等五项指标的空间变异特征。对比不同采样部位不同采样尺度下重金属元素空间结果,探讨样点空间分布变化对表层沉积物空间预测精度的影响。研究结果表明,各元素空间最优拟合模型中变程最小为98m,认为湿地区最优且最密采样点距拟定为98m较为合理。

This paper adopts statistical and spatial autocorrelation analysis methods to conduct a study on the geochemical survey scale of wetland ecosystems around the Taohuajiang river reservoir and its watershed.In total,110 surface sediment samples were collected to investigate the spatial variability characteristics of critical environmental quality assessment factors,including Cd,Hg,As,Pb,and Cr in the surface sediments.By comparing spatial results of heavy metals at different sampling sites and under various sampling scales,this study examines the impact of sample point spatial distribution changes on the spatial prediction accuracy of surface sediment.The results demonstrate that the smallest range in each element's optimal spatial fitting model is 98 meters,which leads to the consideration that a sampling point distance of 98 meters is a reasonable and optimally dense choice for the wetland area.