草地利用方式对藏嵩草沼泽化高寒草甸植被和土壤特征的影响  

Impact of different grazing utilization on vegetation and soil characteritics of Kobresia tibetica swamp alpine meadow

作　　者：魏巍 周娟娟 刘云飞 白玛嘎翁 仁增旺堆 WEI Wei;ZHOU Juan-juan;LIU Yun-fei;BAIMA Ga-weng;RENZENG Wang-dui(State Key Laboratory of Highland Barley and Yak Germplasm Resources and Genetic Improvement Lhasa 850000,China;Institute of Pratacultural Science,Tibet Academy of Agriculture and Animal Husandry Science,Lhasa 850000,China)

机构地区：[1]省部共建青稞和牦牛种质资源与遗传改良国家重点实验室,西藏拉萨850000 [2]西藏自治区农牧科学院草业科学研究所,西藏拉萨850000

出　　处：《草原与草坪》2022年第4期55-61,共7页Grassland and Turf

基　　金：省部共建青稞和牦牛种质资源与遗传改良国家重点实验室自主课题(XZNKY-2020-C-007Z04);西藏自治区自然科学基金项目(XZ2019ZRG-96)。

摘　　要：探讨草地不同利用方式下西藏藏嵩草沼泽化高寒草甸植被特征和土壤养分特征,为其合理利用提供数据支撑。以当雄县羊八井镇藏嵩草沼泽化高寒草甸为研究对象,选定放牧+刈割处理(M+G)、生长季休牧处理(WG)和全年放牧(FG)3种传统的草地利用方式,进行植物多样性分析和土壤碳、氮、磷养分的测定。结果表明:全年放牧处理藏北嵩草(Kobresia littledalei)呈斑块化退化趋势,高山嵩草(K.pygmaea)、藏豆(Stracheya tibeticum)、高山紫菀(Aster alpinus)、蒲公英(Taraxacum mongolicum)、鹅绒委陵菜(Potentilla anserina)、二裂委陵菜(P.bifurca)、独一味(Lamiophlomis rotata)等低矮化指示植物的重要值均增加。放牧+刈割利用方式在获得较高草地生物量的同时,显著降低了群落的丰富度和Shannon-Wiener多样性;土壤有机碳、全氮含量均随土层深度增加明显下降,放牧+刈割处理土壤有机碳和全氮含量显著低于生长季休牧和全年放牧处理;而全年放牧样地的土壤全磷含量高于其他两类利用样地。放牧+刈割利用方式可能加速土壤养分的流失,全年高强度的放牧利用是造成植被退化的主要因素,生长季休牧可有效利用草地资源,实现草地的可持续利用。To explore the characteristics of vegetation and soil nutrients of K.tibetica swamp alpine meadow in Dangxiong county,the plant diversity and soil carbon,nitrogen and phosphorus were analyzed and determined by se⁃lecting three traditional types of grassland grazing utilization:moving+winter-spring grazing(M+G),winter graz⁃ing(WG),free grazing(FG).The results showed that there were 19 plant species in the Kobresia wetlands meadow community under different grazing utilization.These plant species belong to 10 families and 15 genera,and Kobresia of Cyperaceae family was the dominant plant.Under the FG,K.littledalei showed a tendency of patching and degra⁃dation,K.pygmaea,Stracheya tibeticum,Aster alpinus,Taraxacum mongolicum,Potentilla anserina,P.bifurca and Lamiophlomis rotata showed an increase in the important values of plants.The M+G utilization not only obtained higher grassland biomass,but also significantly reduced the richness of community and Shannon-Wiener diversity.Soil organic carbon and total nitrogen decreased with the increase of soil depth;the content of soil organic carbon and total nitrogen of M+G were significantly lower than those of WG and FG.The total phosphorus of FG was signifi⁃cantly higher than that of M+G and WG.In summary,the M+G utilization could accelerate the loss of soil nutri⁃ents;the high⁃intensity grazing utilization throughout the year could be the main factor causing vegetation degrada⁃tion.The winter grazing could provide the sustainable utilization of the grassland in the K.tibetica swamp alpine meadow through effective utilization of the grassland resources.

关 键 词：沼泽化高寒草甸 草地利用方式 植被数量特征 土壤养分 

分 类 号：S812.2[农业科学—草业科学]