紫色土NH_4^+、NO_3^-的吸附-解吸特性研究  

Research on the adsorption and desorption characteristics of ammonia and nitrate in purple soil

作　　者：谢红梅[1] 朱波[2] 朱钟麟[1] 

机构地区：[1]四川省农科院土肥所农业部长江上游农业资源环境重点开放实验室,成都610066 [2]中科院成都山地灾害与环境研究所,成都610041

出　　处：《土壤肥料》2006年第2期19-22,共4页Soils and Fertilizers

基　　金：中科院知识创新工程重大项目(KZCX2-413);四川省青年科技基金;四川省科技攻关计划(04NG020-015)<稻田保护性耕作关键技术研究与示范>;国家863节水农业项目(2002AA2Z4266)<节水农业效益评估方法研究与指标体系构建>

摘　　要：试验在25±1℃恒温条件下研究了紫色土NH4+、NO3-的吸附-解吸特征。结果表明,紫色土对NH4+、NO3-的等温吸附曲线与Freundlich模型相关性强,均达到极显著水平。在低浓度时,NH4+、NO3-的等温吸附线斜率较大;在高浓度时,等温吸附线趋于平缓;土壤吸附态NH4+、NO3-的解吸曲线与Freundlich方程拟合度高,达到极显著水平,而与Langmiur方程拟合较差;通过K吸附和K解吸值的大小比较,找出了土壤NO3-比NH4+更易于流失的根本原因。The adsorption and desorption characteristics of ammonia and nitrate in purple soil were researched in this paper under the condition of 25 ± 1 ℃. The result showed that both ammonia and nitrate adsorption curves could be well described by Freundlich equation, however, the isothermal adsorption of ammonia and nitrate by purple soil fitted bad Langmiur equation. In low concentration the slop of adsorption curves on ammonia and nitrate were high. With the increase of concentration the adsorption curves of ammonia and nitrate were smoothness. The isothermal desorption of ammonia and nitrate fitted well with Freundlich equation rather than Langmiur equation; Compared with the values of Kads and Kdes between ammonia and nitrate the critical reason that nitrate move more easily than ammonia was found.

关 键 词：紫色土 NH4^+ NO3^- 吸附 解吸 土壤流失 

分 类 号：S153[农业科学—土壤学]