摘要
采用Bowman-cole有机磷分级法研究了典型棕壤及其各级微团聚体中有机磷组分在林地、柞树林地、耕地3种土地利用方式下的变化情况.结果表明,有机磷总量在3种利用方式下表现为林地＞耕地＞柞树林地,有机磷占全磷的比例却为林地＞柞树林地＞耕地.土地利用方式对棕壤活性有机磷和高稳性有机磷的含量及有效性影响甚微,开垦为耕地可保持中活性有机磷含量并提高其有效性,开垦为柞树林地则显著降低其含量,耕垦可显著降低耕地中中稳性有机磷含量及其比例.耕垦可以降低有机磷总量在各级微团聚体中的含量,且降低率随粒级的增大而增加,提高50～250 μm粒级活性有机磷的有效性,降低＜10 μm和50～250 μm粒级中的中活性有机磷含量,开垦为耕地有利于＜10 μm粒级中其有效性的保持,可显著降低10～50 μm和50～250 μm粒级中稳性有机磷含量,尤其显著降低耕地中其占有机磷的比例,开垦为柞树林有地有利于高稳性有机磷在各粒级中的分解转化,开垦为耕地的却有利于高稳性有机磷在10～50 μm和50～250 μm粒级中累集.
The effect of three land use patterns(secondary-forestland(SL),tussah-woodland(TL) and farmland(FL)) on the content and forms of organic phosphorus in brown earth(0~20 cm) and microaggregates was studied by Bowman-cole method.Results showed that the content of total organic phosphorus(TOP) under three land use patterns was SL>FL>TL,but the ratio of TOP to total P(TP) was SL>TL>FL.There was no significant difference in the content and availability of liable organic P(LOP) and moderately resistant organic P(MROP) among three land use patterns.The amounts of moderately liable organic P(MLOP) can be preserved and increased availability of it by cultivation to FL,but significantly decreased the content of it by cultivation to TL,reclamation significantly decreased moderately organic P(MOP) and the ratio of MOP to TOP under farmland.Reclamation reduced the content of TOP in different size microaggregates and with particle size increasing the rate of reducing was increased.Reclamation also enhanced availability of LOP in 50~250 μm particle size,significantly decreased the content of MLOP in <10 μm and 10~50 μm particle size,but helped to preserve availability of it in <10 μm particle size under FL,decreased the content of MOP in 10~50 μm and 50~250 μm particle size,especially decreased the ratio of MOP to TOP under FL.MROP decomposed in different soil microaggregates by cultivation to TL,but accumulated in 10~50 μm and 50~250 μm particle size by cultivation to FL.
出处
《水土保持学报》
CSCD
北大核心
2007年第4期141-144,共4页
Journal of Soil and Water Conservation
关键词
土地利用方式
棕壤
微团聚体
有机磷组成
land use pattern
brown earth
microaggregates
forms of organic phosphorus
