放牧管理模式对高寒草甸草原土壤养分特征的影响

为探讨不同放牧管理模式下高寒草甸草原土壤养分特征的变化,对青藏高原东缘禁牧(NG)、全生长季休牧(RG)、传统夏季休牧(TG)和连续放牧(CG)4种放牧管理模式下高寒草甸草原土壤有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾含量进行测定和分析。结果表明:(1)NG显著增加了0~30cm土层有机质含量,RG和TG显著增加了0~20cm土层有机质含量;(2)NG,RG和TG显著提高了高寒草甸草原0~30cm土层全氮含量和20~30cm土层速效氮含量,而降低了0~10cm土层的速效氮含量;(3)NG,RG和TG显著提高了高寒草甸草原0~30cm土层全磷和速效磷含量;(4)不同模式放牧对高寒草甸草原土壤全钾含量无显著影响,但总体上,NG,RG和TG高于CG;NG,RG和TG降低了0~10cm土层速效钾含量,而显著增加了10~30cm土层速效钾含量。连续放牧使土壤养分流失严重,从而导致土壤肥力降低,而禁牧和季节性休牧能有效增加青藏高原东缘高寒草甸草原土壤的养分含量,是该区和类似区域草地放牧管理的理想选择。

Effect of different grazing management on soil nutrient characteristics in alpine meadow-steppe

To study the changes of soil nutrient characteristics under different grazing management in alpine meadow-steppe ecosystem on eastern margin of Qinghai-Tibet Plateau.The study investigated the soil organic matter,total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus and available potassium in 4 sites with different grazing managements,which were non-grazing(NG),rest grazing in growing stage(RG),traditional grazing (TG)and continuous grazing (CG).The results revealed that soil organic matter in 0~30 cm soil layer in NG was significantly higher than that in RG,TG and CG,and soil organic matter in 0~20 cm soil layer in RG and TG was significantly higher than that in NG and CG.NG,RG and TG significantly improved total nitrogen content in 0~30 cm soil layer and available nitrogen content in 20~30 cm soil layer but reduced the available nitrogen content in 0~10 cm soil layer.The total soil phosphorus and available phosphorus content of alpine meadow-steppe in 0~30 cm soil layer was significantly higher in NG,RG and TG than those in CG.Different grazing management had no significant effect on soil total potassium content,but on the whole,the total potassium content in NG,RG and TG was higher than that in CG.It is concluded that continuous grazing reduced soil nutrient result in soil fertility decrease,and non-grazing and seasonal rest grazing can effectively in-crease the soil nutrient content in alpine meadow-steppe.NG and RG were recommended grazing management in the regions or the similar regions.