Effects of Soil Porosity on Available Cd Content Extracted by DGT

doi:10.11924/j.issn.1000-6850.casb15110071

Abstract

Abstract: DGT is an important tool for the evaluation of heavy metal effectiveness, but the DGT extraction is affected by soil porosity, and so far still lacks relevant research. The authors used different levigation levels of soil to change the soil porosity, studied the effect of soil porosity on the available Cd content extracted by DGT. The results showed that levigation changed the soil porosity, thereby affected the soil diffusion boundary layer, and then affected the three expression forms of available Cd (C_DGT, C_E and C′_E), and had the biggest impact on C_DGT. After an overall consideration of those influencing factors, the results indicated that the porosity changes caused by levigation had limited impact on soil available Cd content, its variability was less than 10%, but the porosity and diffusion boundary layer change should be considered in calculation to reduce the error.

CLC Number:

Song Zhiting,Zhao Yujie,Zhou Qiwen,Liu Xiaowei,Pan Yang,Tian Nana,Mu Li and Shi Rongguang. Effects of Soil Porosity on Available Cd Content Extracted by DGT[J]. Chinese Agricultural Science Bulletin, 2016, 32(12): 139-144.

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