A Comparison of Five Different Techniques to Determine Hydraulic Conductivity of a Riparian Soil in North Bavaria, Germany  

作　　者：Edzard HANGEN Friedhelm VIETEN 

机构地区：[1]Department of Preventive Soil Protection and Soil Monitoring, Bavarian Environment Agency

出　　处：《Pedosphere》2018年第3期443-450,共8页土壤圈（英文版）

摘　　要：Soil saturated hydraulic conductivity(K_s) is a predominant input factor when forecasting the vertical transport of contaminants through the soil or when estimating the flood retention capacity of the soil. Displacement of contaminants in the soil over extended periods of time can be attributed mainly to matrix flow, whereas flow through macropores becomes significant under untypically wet conditions, e.g., during spills or rain storms. To obtain matrix conductivities for a soil, the effects of macropores should be excluded.However, the K_s values of a soil profile are unlikely to be reflected solely by pedotransfer tables based on soil texture and bulk density.In this study, we examined five different methods(pedotransfer table, soil core, borehole permeameter, particle-size distribution curve, and instantaneous profile) to determine K_s values for a mercury-contaminated riparian soil for subsequent simulation of longterm mercury displacement toward groundwater. We found that the determined K_s values increased in the following order: borehole permeameter < particle-size distribution curve < pedotransfer table < instantaneous profile < soil core. The instantaneous profile method yielded K_s values of matrix flow, which additionally reflected the structure-related features of K_s values as provided by the soil core method. Despite being labor intensive and requiring expensive field sensors, the instantaneous profile method may provide the best representative in-situ K_s values for the studied site.Soil saturated hydraulic conductivity （Ks） is a predominant input factor when forecasting the vertical transport of contaminants through the soil or when estimating the flood retention capacity of the soil. Displacement of contaminants in the soil over extended periods of time can be attributed mainly to matrix flow, whereas flow through macropores becomes significant under untypically wet conditions, e.g., during spills or rain storms. To obtain matrix conductivities for a soil, the effects of macropores should be excluded. However, the Ks values of a soil profile are unlikely to be reflected solely by pedotransfer tables based on soil texture and bulk density. In this study, we examined five different methods （pedotransfer table, soil core, borehole permeameter, particle-size distribution curve, and instantaneous profile） to determine Ks values for a mercury-contaminated riparian soil for subsequent simulation of long- term mercury displacement toward groundwater. We found that the determined Ks values increased in the following order： borehole permeameter 〈 particle-size distribution curve 〈 pedotransfer table 〈 instantaneous profile 〈 soil core. The instantaneous profile method yielded Ks values of matrix flow, which additionally reflected the structure-related features of Ks values as provided by the soil core method. Despite being labor intensive and requiring expensive field sensors, the instantaneous profile method may provide the best representative in-situ Ks values for the studied site.

关 键 词：borehole permeameter contaminant transport Gleysol instantaneous profile method particle-size distribution curve pedotransfer table soil core 

分 类 号：S152.7[农业科学—土壤学]