抚仙湖流域不同农业模式砾质土壤环境质量及其氮磷流失风险评估  

Risk assessment on soil environment quality and losses of nitrogen and phosphorus for the gravel soils under different farming practices in the watershed of Lake Fuxian

作　　者：夏天翔[1] 李文朝[1] 潘继征[1] 

机构地区：[1]中国科学院南京地理与湖泊研究所

出　　处：《湖泊科学》2008年第1期110-116,共7页Journal of Lake Sciences

基　　金：国家863项目(2005AA60101004)资助．

摘　　要：于2006年8月分层采集抚仙湖流域有机及传统农业农田砾质土壤,对土壤样品的机械组成、重金属含量、养分剖面积累进行测定分析;通过室内降雨模拟,对不同土壤样品氮磷流失风险进行评估.结果表明:①有机及传统农业模式下,砾质土壤机械组成发生明显变化,0-20cm土层砂粒含量明显降低:②除传统农业土壤Cd为二级标准,其他土壤重金属含量均符合国家土壤环境质量(GB/15618-1995)一级标准:③有机及传统农业模式下0-20cm土层有机质、全氮养分明显积累,但不同农业模式问无明显差异:有机农业土壤全磷、水溶性氮磷积累程度显著高于传统农业土壤;④有机农业土壤在780mm模拟降雨条件下,氮、磷流失风险更大,氮、磷流失总量分别是传统农业土壤的1.9倍、19.8倍.On August 2006, grave soils from organic and conventional farming were sampled within the watershed of Fuxian Lake in Yunnan Province. Soil granule composition, heavy metal contents and nutrition accumulation in the soil profile were determined. Nitrogen and phosphorus losses from the soils were assessed by the in-door rainfall simulation. The results were as below： 1） both organic and conventional farming practices significantly lower the soil sand content on the 0-20 cm soil profile; 2） all soil heavy metal contents met the Class A standard of National Environment Quality Standard for Soils （GB/15618-1995） except Cd which only met Class B standard; 3） soil total nitrogen and organic matter accumulated in the 0-20 cm soil profile, and showed no significant differences between organic and conventional farming practices. The accumulation of soil total phosphorus, NO3-N and water dissolved phosphorus （WSP） under the organic farming practice is significantly higher than those under conventional farming practice; and 4） under the condition of 780 mm rainfall simulation, the risk of nitrogen and phosphorus losses from the organic farming soil is higher than that from the conventional farming. Total amount of nitrogen and phosphorus losses from the organic farming soil were 1.9 and 19.8 times higher than those from the conventional farming soil, respectively.

关 键 词：砾质土 土壤环境质量 氮 磷 流失 抚仙湖 

分 类 号：S158[农业科学—土壤学] X52[农业科学—农业基础科学]