Uncertainty analysis of regional cultivated land soil cadmium pollution assessment under different sampling densities
To explore the uncertainty in the assessment of cadmium(Cd)pollution in regional cultivated land soil under the influence of sampling density and location,this study utilized intensive survey samples from a region in China with severe Cd pollution in cultivated land soil.Through the use of multi-scale sampling grids(500,1 000,1 500,2 000 m)and random sampling,a large number of samples were obtained.Subsequently,the overall level of Cd content in regional cultivated land soil,spatial variation characteristics,and the uncertainty of pollution risk assessment results were analyzed.The results showed that the uncertainty in the overall assessment of Cd content in regional cultivated land soil is low,with an average value of 7% .However,the uncertainties in spatial variation characteristics and pollution risk assessment results were high,with average values of 32.2% and 30.1%,respectively.This uncertainty increased as the sampling density decreased.Even with sparse sampling,the median or geometric mean could effectively assess the overall level of Cd content in regional cultivated land soil to some extent.However,to effectively characterize the spatial distribution of soil Cd content and identify pollution risks,appropriately high-density sampling was still necessary.The high uncertainty in the spatial distribution characteristics of soil Cd content and pollution risk assessment results may be attributed to the complex interplay of small-scale randomness and multi-scale structural effects on Cd content in cultivated land soil.
国家科技期刊平台
NSTL
万方数据
