Effects Of Vegetation On Soil Phosphorus Fractions And Mineralization In Qinghai-Tibet Plateau

Higher soil organic phosphorus content in alpine meadow of Qinghai-Tibet plateau, the amount of available phosphorus is relatively small,but soil organic phosphorus can be converted to available phosphorus by mineralization,which can be absorbed by plants. Therefore, in which contain low amounts of inorganic phosphorus in soil, soil organic phosphorus mineralization is extremely important. This study is randomly selected three different research sites in an alpine meadow of Qinghai-Tibet plateau, patches of potentilla fruticosa shrub and the grassland between the potentilla fruticosa shrub patches as the object of study, to exploration the potential of soil organic phosphorus mineralization by incubation in the laboratory. We randomly selected three sampling plots at each of the three sites, each plot has three repetitions, and core samples from depths of 0-10 cm,10-20cm were taken separately. Soil sample for the determination of basic biochemical properties and the determination of mineralization of nitrogen and phosphate.The following results are obtained:the 0-20cm soil in three sites, the amount of cumulative mineralization is gradually increased, and with incubation period extended, the amount of cumulative mineralization increased. But organic phosphorus mineralization rates over incubation period presents the first increased and then decreased trend. Mineralization of soil organic phosphorus and mineralization rate in patches of potentilla fruticosa shrub and the grassland between the potentilla fruticosa shrub patches are significantly different, and significantly associated with nitrogen mineralization in soil. Results showed that higher potential of organic phosphorus mineralization in patches of potentilla fruticosa shrub, and higher phosphorus availability in patches of potentilla fruticosa shrub.