土壤电场和机械组成对土壤磷迁移的影响  

Effects of soil electric field and mechanical composition on soil phosphorus migration

作　　者：谢佩玲 谭立 李航 刘新敏 XIE Peiling;TAN Li;LI Hang;LIU Xinmin(Laboratory of Soil Multi-scale Interfacial Process,Southwest University,College of Resources and Environment,Chongqing 400716,China;Hanhong College Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学资源环境学院,土壤多尺度界面过程与调控重庆市重点实验室,重庆400716 [2]西南大学含弘学院,重庆400715

出　　处：《环境工程学报》2024年第3期886-896,共11页Chinese Journal of Environmental Engineering

基　　金：国家级大学生创新创业训练计划项目(202210635112)。

摘　　要：土壤磷随水迁移是土壤侵蚀和农田面源污染发生的重要因素之一。本研究通过电解质浓度和类型(Na^(+)和K^(+))调节土壤电场,通过加入直径为2~3 mm的石英砂颗粒来调节土壤的机械组成,探究土壤电场和机械组成对土壤磷迁移的影响。结果表明:1)土壤磷迁移主要以颗粒态磷为主,例如,在浓度为0.01 mol·L^(-1)的Na^(+)体系中,颗粒态磷迁移量是溶解态磷迁移量的31倍;2)与Na^(+)相比,K^(+)能显著降低土壤电场,减少土壤颗粒态磷而增加溶解态磷的迁移;3)土壤颗粒态磷和溶解态磷的迁移量均随电解质浓度增加而降低,电解质浓度增加降低土壤电场强度和作用力程,土壤团聚体稳定性增强,从而有利于土壤磷的保持;4)添加石英砂后改变了土壤机械组成,能够显著改变土壤磷的迁移规律,且与离子类型有关;5)土壤电场和机械组成共同作用控制着土壤磷的迁移。本研究可为土壤磷迁移以及农田面源污染防控提供一定理论参考。Soil phosphorus migration with water is one of the important factors in the occurrence of soil erosion and farmland non-point source pollution.In this study,the effects of soil electric field and mechanical composition on phosphorus migrations were investigated.Specifically,soil electric field and mechanical composition were respectively regulated by electrolyte concentrations and types(Na^(+)and K^(+))as well as the quartz sand particles with a diameter of 2~3 mm.The results indicated that:1)soil phosphorus migration was dominated by particulate phosphorus.For example,in 0.01 mol·L^(-1)Na^(+)system,the migration quantity of particulate phosphorus was 31 times higher than that of dissolved phosphorus.2)Compared with Na^(+),K^(+)significantly reduced soil electric field,which in turn reduced soil particulate phosphorus while increased dissolved phosphorus migration.3)Migration quantity of both soil particulate phosphorus and dissolved phosphorus decreased with increasing electrolyte concentration.An increase in the electrolyte concentration decreased the strength and force range of soil electric field,which favored the soil aggregate stability and soil phosphorus retention.4)Addition of quartz sand changed soil mechanical composition,which can significantly change the migrations of soil phosphorus;additionally,the aforementioned change was related to ion type.5)Soil phosphorus migrations were determined by both soil electric field and mechanical composition.This study provides some theoretical reference for the migrations of soil phosphorus and the prevention/control of farmland non-point source pollution.

关 键 词：土壤颗粒相互作用 土壤电场 机械组成 磷迁移 

分 类 号：X522[环境科学与工程—环境工程]