摘要
以黄绵土为试验材料 ,通过模拟降雨试验研究了翻耕与压实 (分别代表大田条件下土壤翻耕与免耕两种休闲方式 )条件下坡地土壤中不同形态P的流失特征 .结果表明 ,翻耕条件下 ,由于坡面产流产沙量增加 ,流失径流中溶解态磷 (DP)、泥沙浸提态磷 (SEP)以及泥沙全磷 (STP)的含量与流失量均明显增加 ,增幅达 10倍以上 .P的流失形态以泥沙结合态为主 .压实条件下 ,DP/生物有效磷 (BAP)与BAP/径流总磷(TP)比率分别为 15 %和 2 4 % ;而翻耕条件下DP/BAP与BAP/TP比率分别为 12 %和 2 6 % .在黄土高原地区实行免耕或者夏季留茬休闲 ,可有效降低坡地土壤与养分的流失量 ,有效遏制土壤退化 。
Intensive soil erosion and nutrient loss from slope land not only resulted in the serious degradation of soil quality,but also threatened the water environment of the lower area.In this paper,a simulated rainfall experiment with loessial soil was conducted to study the characteristics of the loss of different phosphorus forms under the conditions of tillage and compaction(no-tillage).The results showed that in comparing with compaction,tillage increased the loss of dissolved P(DP),sediment extractable P(SEP)and sediment total P(STP)by 10 times due to the increase of runoff and sediment amount. The forms of the lost P were mainly sediment-combined P,and the ratios of DP/BAP and BAP/TP in the lost runoff were 12% and 2.6% under compaction,and 15% and 2.4% under tillage,respectively. The application of no-tillage or mulch-keeping fallow in Summer was effective to decrease soil and nutrient loss from slope land,which would be effective and significant both to soil degradation prevention and water environment protection in the lower area of Loess Plateau.
出处
《应用生态学报》
CAS
CSCD
2004年第3期443-448,共6页
Chinese Journal of Applied Ecology
基金
国家杰出青年基金项目 ( 4 0 0 2 5 10 6)
国家自然科学基金重大项目( 90 10 2 0 12 )
国家自然科学基金资助项目 ( 4 0 3 710 74)
