不同磷水平塿土的表面性质及其对磷素流失特征的影响  

The Surface Properties of Lou Soil with Different Phosphorus Levels and Their Effects on the Loss of Phosphorus

作　　者：胡良 杜伟 常博焜 曹钢 杨学云[1,2] 吕家珑 HU Liang;DU Wei;CHANG Bokun;CAO Gang;YANG Xueyun;LÜJialong(College of Natural Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China;Northwest Key Laboratory of Plant Nutrition and Agricultural Environment,Ministry of Agriculture and Rural Affairs,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]农业农村部西北植物营养与农业环境重点实验室,陕西杨凌712100

出　　处：《土壤学报》2023年第2期424-434,共11页Acta Pedologica Sinica

基　　金：陕西省耕地土壤环境质量类别划分及受污染耕地修复示范项目(NYKJ-2021-YL(XN)19);陕西省自然科学基础研究计划项目(2021JQ-170);国家重点研发专项项目(2017YFD0200205)资助。

摘　　要：为明确不同磷水平塿土的表面电化学性质特征,阐明电解质浓度调控下塿土表面性质的变化及其与土壤磷素流失特征的内在关联,利用物质表面性质联合测定分析技术,结合降雨模拟试验,研究了长期定位配施磷肥条件下不同磷水平塿土的表面电化学性质及其对土壤磷素流失特征的影响。结果表明:(1)长期施磷处理下的塿土全磷含量为不施磷处理的2.46倍,但其表面电位、表面电荷密度、表面电场强度、比表面积以及表面电荷数量均低于不施磷处理塿土;(2)不同磷水平塿土均表现出土壤颗粒及磷素流失量随着土粒表面电位(绝对值)升高而加剧的趋势,颗粒态磷的累积流失量与土壤颗粒累积流失量间呈线性正相关;(3)由于低磷水平塿土表面电位(绝对值)相对较高,所受土壤颗粒间静电排斥力更大,导致土壤团聚体稳定性较差,土壤颗粒及其附着磷素累积流失量更多;(4)本实验条件下土壤中磷素流失以颗粒态磷为主,占流失总量的81%~99%,溶解态磷占比十分有限。本研究阐明了长期定位施磷处理对土壤表面电化学性质的影响,明确了表面性质变化与土壤颗粒及磷素流失特征的关系,为长期施磷土壤的环境风险防控提供了新思路。【Objective】This study was designed to identify the surface electrochemical characteristics of Lou soil with different phosphorus levels and to study the transportation processes of phosphorus in the soil solid-liquid phase.Also,the relationship with soil surface properties was investigated and the change of surface properties of Lou soil under controlled electrolyte concentration and its internal relevance with phosphorus loss were clarified.【Method】The number of soil particles and phosphorus loss of Lou soil under different electrolyte concentrations was obtained by rainfall simulation test.The surface chemical properties of the soil were determined by combined measurement and analysis of surface properties.Also,the surface electrochemical properties of Lou soil with different phosphorus levels and their effects on soil phosphorus loss under the condition of long-term localized application of phosphate fertilizer were studied.【Result】The results show that:(1)The total phosphorus content of Lou soil treated with long-term application of phosphate fertilizer is 2.46 times larger than that of Lou soil treated without phosphate fertilizer.However,the former’s surface potential,surface charge density,surface electric field strength,specific surface area,and surface charge number were lower than those of Lou soil without the application of phosphorus;(2)For Lou soils with different phosphorus levels,the cumulative loss of soil particles and phosphorus tended to intensify with an increase in the surface potential(absolute value)of soil particles.There was a linear positive correlation between the cumulative loss of particulate phosphorus(PP)and the cumulative loss of soil particles;(3)The surface potential(absolute value)of Lou soil with lower phosphorus content was larger than that of Lou soil with higher phosphorus content,and the electrostatic repulsion between soil particles was larger,resulting in poor stability of soil aggregates and more cumulative loss of soil particles and their attached phosphor

关 键 词：定位试验 土壤表面电化学性质 团聚体稳定性 磷流失 颗粒态磷 溶解态磷 

分 类 号：S153.3[农业科学—土壤学]