摘要
对子午岭林区农业及林草植被下土壤磷素的分布与变化进行了研究,结果表明:林草植被有利于促进土壤大的水稳性团聚体的形成,大团聚体的含量随土层深度增加而下降。在草地中,植物根系推动了下层土壤中的磷素向上迁移,使上层土壤全磷含量显著高于下层土壤中的含量。在林地土壤中,处于腐解过程中的凋落林冠叶片和表层土壤中的可溶性磷,在水分入渗的作用下,向亚表层土壤中迁移,使亚表层土壤全磷含量提高。这说明草本植物和乔木林驱动土壤全磷垂直分布的机理不同。林草植被土壤中,分布在>0.25 mm的各粒级团聚体中全磷量随着土层深度的增加而下降,而分布在<0.25 mm的团聚体中全磷量随土层深度的增加而提高,生长林草植被有益于促进上层土壤中磷素分布在大的团聚体中,同时磷素也促进了大团聚体的形成和保持。
The study on the change and distribution of phosphorus(P)in soils grown crops,grass or forest was conducted in Ziwuling Mountain.The contents of different sizes of macroaggregates declined with the increase in soil depth in grassland or forestland.In the grassland,the roots of grass caused the P in deep soil layers to move to the topsoil,which resulted in the level of P in topsoil was greater than that in the subsoil.And in the forestland,the dissolved P derived from decaying leaves or topsoil moved to subsoil due to water movement,which caused that the contents of P in subsoil was greater than that in topsoil.It could be seen that the mechanisms driving P distribution in soil profile were different between grass and forest.It was understood that grass and forest could promote the formation of soil macroaggregate.P distributed in the aggregate sizes of>0.25 mm decreased with the increase in soil depth,and P distributed in the aggregate sizes of<0.25 mm,in turn,rose with the increase in soil depth in grassland or forestland.These results suggested that growth of grass or forest could make P distribute in the macroaggregates and P could lead the formation of macroaggregates and the stability of aggregates in the grassland or forestland.
作者
韩馥
王百群
张尚鹏
喻佳洛
HAN Fu;WANG Baiqun;ZHANG Shangpeng;YU Jialuo(Institute of Soil and Water Conservation,Northwest A&F University,Yangling,Shaanxi712100,China;Sate Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Northwest A&F University,Yangling,Shaanxi712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and ministry ofWater Resources,Yangling,Shannxi712100,China;University of Chinese Academy of Sciences,Beijing100049,China)
出处
《水土保持研究》
CSCD
北大核心
2019年第5期118-122,共5页
Research of Soil and Water Conservation
基金
国家自然科学基金(40301024),国家自然科学基金国际(地区)合作与交流项目(41561144011)
黄土高原土壤侵蚀与旱地农业国家重点实验室专项经费(A314021403-C6)
中国科学院野外站联盟项目(KFJ-SW-YW029~05)
科技基础性工作专项:农田生态系统资源分布与生源要素现状调查(2014FY210112)
关键词
土壤团聚体
土壤磷素
植被
子午岭
soil aggregate
soil phosphorus
vegetation
Ziwuling Mountain