我国23个土壤磷素淋失风险评估 Ⅱ.淋失临界值与土壤理化性质和磷吸附特性的关系  

The evaluation of phosphorus leaching risk of 23 Chinese soils Ⅱ.The relationships between soil properties,P adsorption characteristics and the leaching criterion

作　　者：赵小蓉[1] 钟晓英[1] 李贵桐[1] 鲍华军[1] 李浩浩[1] 熊桂荣[2] 林启美[1] 

机构地区：[1]中国农业大学资源与环境学院,北京100094 [2]湖北省农业科学院植物保护与土肥研究所,武汉430064

出　　处：《生态学报》2006年第9期3011-3017,共7页Acta Ecologica Sinica

基　　金：英国文化委员会资助项目;长江学者和创新团队发展计划资助项目(IRT0142);中国科学院知识创新工程资助项目(KZCX3-SW-426)~~

摘　　要：从13个省(市)采取23个耕地表层土壤,通过室内模拟试验测定其磷素淋失临界值和pH、有机质、<0.01mm、<0.002mm、交换性钙镁、活性铁铝、磷等温吸附特性等,以建立土壤磷素淋失临界值与土壤基本理化性质和磷吸附特性之间的关系。结果表明:土壤pH<6.0时,随土壤pH提高临界值增加,土壤pH与临界值之间呈显著的指数关系;而当土壤pH>6.0时,随土壤pH提高临界值减小,在pH6.5左右土壤磷素淋失临界值最高。土壤磷素淋失临界值与土壤有机质、活性铁(铝)、交换性钙之间存在显著的相关,而与交换性镁、CEC、<0.01mm、<0.002mm、K、Qm的相关性受土壤酸碱度影响。可以通过测定土壤有机质或活性铁的含量,来计算土壤磷素淋失临界值,评价土壤磷素淋失的风险。供试的23个土壤,除了采自湖北潜江的20号水稻土存在比较大的磷素淋失风险,其余土壤发生磷素淋失的风险很小。23 soils were collected from the croplands of 13 Chinese provinces. Their P leaching criterions were determined by laboratory experiments. Soil parameters including pH, organic matter, cation exchange capacity （CEC）, 〈 0.01mm, 〈 0.002mm, exchangeable Ca and Mg, active A1 and Fe, and P adsorption isotherm were measured at same time. The purpose of this work was to establish the relationships between the soil properties and the P leaching criterions obtained from the relationships between Olsen-P and CaCl2-P. The results showed that the P leaching criterions increased exponentially with soil pH 〈 6.0, but decreased with soil pH 〉 6.0. The highest value was found at about soil pH6.5. There were close relationships between soil P leaching criterions and soil organic matter, active Fe （Al）, exchangeable Ca. In general, exchangeable Mg, CEC, 〈 0.01mm, 〈0.002mm, K and Qm were not significantly related with P leaching criterions. However, the relationships were high in pH 〈 6.0 soils. It is concluded that soil P leaching criterions can be estimated from either soil organic matter or active Fe （Al） contents. Accordingly, the tested 23 soils, except the paddy rice soil No. 20 from Qianjiang Hubei Province, had low risk of P leaching occurrence.

关 键 词：土壤 磷素淋失临界值 土壤物理化学性质 磷吸附特性 

分 类 号：X592[环境科学与工程—环境工程]