西藏藏北地区不同草原类型区土壤理化性质特征研究

The Soil Physical and Chemical Properties of Different Steppe Types in Northern Tibet

[目的]明确西藏藏北地区不同草原类型理化性质状况。[方法]将藏北地区草原进行划分,并随机采取样品,测定表层土（0~20cm）含水量、有机质、全磷和速效磷的含量。[结果]不同草原类型表层土的含水量由高到低依次为高寒沼泽草甸、高寒草甸、高寒灌丛草甸、高寒半荒漠化草原;不同草原类型表层土的有机质含量由高到低依次为高寒沼泽草甸、高寒草甸、高寒灌丛草甸、高寒半荒漠化草原;不同草原类型表层土的全磷含量由高到低依次为高寒灌丛草甸、高寒草甸、高寒沼泽草甸、高寒半荒漠化草原;速效磷从高到低依次为高寒沼泽草甸、高寒灌丛草甸、高寒草甸、高寒半荒漠化草原。[结论]今后应加强对退化草原进行保护,并对草原进行合理利用。

[Objective] To find the physical-chemical properties of different steppe types in northern Tibet. [Method]Steppes in northern Tibet were divided and samples were collected randomly. The water content of topsoil,organic matter,content of total phosphorus and available potassium were measured. [Result] Topsoil water contents in different steppe types from high to low were in the order of alpine swamp meadow,alpine meadow,alpine shrub meadow,and alpine semi-desertification steppe. Organic matter content of topsoil from high to low were in the order of alpine swamp meadow,alpine meadow,alpine shrub meadow,and alpine semi-desertification steppe. Total P contents of topsoil from high to low were in the order of alpine shrub meadow,followed by alpine meadow,alpine swamp meadow,alpine semi-desertification steppe. Alpine swamp meadow had the highest available P content of topsoil,followed by alpine shrub meadow,alpine meadow,alpine semi-desertification steppe. [Conclusion] We should strengthen the protection of degraded steppes and carry out rational utilization of topsoil water.