渗育性水稻土渗滤液中的磷组分研究  

FRACTIONATION OF PHOSPHORUS IN LEACHATE FROM PERCOGENIC PADDY SOILS IN THE TAIHU LAKE REGION

作　　者：王小治[1] 盛海君[1] 栾书荣[1] 赵海涛[1] 封克[1] 曹志洪[2] 

机构地区：[1]扬州大学环境科学与工程学院,江苏扬州225009 [2]中国科学院南京土壤研究所,南京210008

出　　处：《土壤学报》2005年第1期78-83,共6页Acta Pedologica Sinica

基　　金：国家重点基础研究发展规划"973"项目(G1999011806);中国科学院南京土壤研究所土壤圈物质循环开放课题(025103)资助

摘　　要：本试验在太湖地区长江岸边砂质渗育性(漏水型)水稻土上进行,研究在麦稻轮作条件下连续两年施用不同磷肥(每季P 0、30、70、150和300 kg hm-2),稻季各层次土壤溶液中(30、60和90 cm)磷的组分,以探讨磷素在剖面中垂直纵向移动的规律。结果表明:施肥处理在施肥初期提高了30 cm处土壤溶液中溶解磷浓度,对60 cm处溶解磷浓度影响不大,对90 cm处溶解磷浓度没有影响。各处理60 cm和90 cm处土壤溶液中溶解磷的浓度几乎全部超过水体富营养化磷的阈值,故在研究该地区水体富营养化时,要注意渗漏磷排放可能的贡献。特别应指出的是,除6月13日对照处理外,各处理90 cm处土壤溶液中的磷均以溶解有机磷为主,占总溶解磷的56%~100%,表明有机磷(外源加入或内源残留的)比无机磷对环境的潜在威胁将更大。A field plot experiment with five P application rates and 4 replications each was conducted on Percogenic paddy soil in the Taihu Lake Region (TLR) in the years of 2002 and 2003 to monitor the concentration and fractionation of dissolved phosphorus (DP) in leachate at different depth. Results indicate that fertilization increases the concentration of DP in leachate at 30cm in depth at the initial stage,has a little effect in leachate at 60cm,and no effect in leachate at 90cm. However,the concentrations of dissolved P in leachates at 60 and 90 cm were higher than 0. 02 mg L^(-1), which suggests that the leaching may contribute to water eutrophication. Dissolved organic phosphorus (DOP) dominated in the leachate at 90 cm during the entire rice-growing season accounting for 56%～100% of the dissolved phosphorus (DP) in all the treatments except the control on Jun-13. The concentration of DOP in the leachate did not increase along with the P application rates in this experiment,indicating that DOP comes mainly from dissolution of the existing soil organic P by leachate and/or from organic manure applied or with irrigation water.

关 键 词：土壤溶液 解磷 水稻土 育性 磷浓度 施肥处理 外源 渗滤液 水体富营养化 溶解有机磷 

分 类 号：S153[农业科学—土壤学] S511[农业科学—农业基础科学]