太湖地区典型水稻土土壤磷素径流流失及其吸持特征的研究

Research on P Runoff Loss in Paddy Soils in the Taihu Lake Region and Its Sorption Characters

[目的]为控制农业非点源污染提供科学依据。[方法]在稻麦两熟种植制度下，研究了太湖地区爽水型、囊水型两种典型水稻土磷素地表径流流失状况和对磷的吸附特性。[结果]在常规施磷水平下，囊水型水稻土土壤磷素年径流流失量大于爽水型水稻土。2000～2001年度的地表径流磷流失量分别为603．2、679．5g／（hm^2·a），而在2001～2002年度时分别为1148．9、1350．3g（hm^2·a）。爽水型水稻土表层土壤磷的最大吸附量（Qm）和最大缓冲容量（MBC）分别为769．23mg／kg和130．00L/kg，均高于囊水型水稻土的Qm（666．67mg/kg）和MBC（66．00L／kg）。囊水型水稻土的PSI值低于爽水型水稻土，二者的PSI值均小于30。[结论]囊水型水稻土磷素更易流失。

[Objective] The study aimed to provide a scientific base to control the pollution of agricultural non-point sources. [Method] Under the double ripe planting system of rice and wheat, the state of P runoff losses and its absorption characters in two kinds of typical paddy soils （the permeable and waterlogged paddy soils） were studied. [Result] The yearly surface runoff P loss in waterlogged paddy soils was bigger than that in permeable paddy soils at the normal level of applying P, that was 603.2 and 679.5 g/（hm^2·a） resp. in 2000 - 2001 year and that was 1 148.9 and 1 350.3 g/（hm^2·a） in 2001 2002 year. The biggest adsorption quantity（Qm,769.23 mg/kg）and buffer capacity （MBC, 130.00 L/kg）of soil surface P in permeable paddy soils was higher than that in waterlogged paddy soils （Qm and MBC of 666.67 mg/kg and 66.00 L/kg resp. ）. The PSI value of waterlogged paddy soils was lower than that of permeable paddy soils and their value were all lower than 30. [Conclusion] The P was more easier runoff in waterlogged paddy soils.