Responses of Plant Community and Soil Properties to Inter-Annual Precipitation Variability and Grazing Durations in a Desert Steppe in Inner Mongolia  

作　　者：WANG Zhen YUN Xiang-jun WEI Zhi-jun Michael P Schellenberg WANG Yun-feng YANG Xia HOU Xiang-yang 

机构地区：[1]Grassland Research Institute,Chinese Academy of Agricultural Sciences [2]Department of Grassland Science,College of Ecology and Environmental Science,Inner Mongolia Agricultural University [3]Semiarid Prairie Agricultural Research Center (SPARC),Agriculture and Agri-Food Canada

出　　处：《Journal of Integrative Agriculture》2014年第6期1171-1182,共12页农业科学学报（英文版）

基　　金：financially supported by the National Basic Research Program of China (2014CB138801);the International Science & Technology Cooperation Program of China (2013DFR30760);the China Postdoctoral Science Foundation (2013M541096);the National Important Research Program of Inner Mongolia,China (2010ZD08);the Central Nonprofit Research Institutes Fundamental Research Funds,China (1610332013015)

摘　　要：Grazing can dramatically affect arid grassland communities that are very vulnerable to environmental changes due to its relatively short and sparse ground coverage, low biomass, sandy soil and inter-annual precipitation found in the desert steppe. The study investigates the effects of different grazing durations on vegetation and soil properties of a desert steppe community. The experiment was conducted in Xisu Banner in Inner Mongolia with ifve treatments：CG （continuous grazing）, 40UG （40 d ungrazed）, 50UG （50 d ungrazed）, 60UG （60 d ungrazed） and UG （ungrazed）. The biomass of both shrub and annual-biennial plant communities were signiifcantly decreased by CG. Continuous grazing and 40UG signiifcantly reduced the ANPP （aboveground net primary productivity） by the end of the three year study. 60UG treatment increased soil organic carbon （OC）, total nitrogen concentration （TN） and total phosphorus concentration （TP） concentrations and 50UG increased the TN and total phosphorus concentration （TK） concentrations, whereas CG, 40UG and 50UG decreased soil OC, TP and available phosphorus concentration （AP） concentrations. The perennial plant species of the desert steppe were generally tolerant for grazing. The annual-biennial plant species had large variability in ANPP because of the inter-annual precipitation. Our results highlight that inter-annual precipitation variations could strongly modify the community responses to grazing in arid ecosystems.Grazing can dramatically affect arid grassland communities that are very vulnerable to environmental changes due to its relatively short and sparse ground coverage, low biomass, sandy soil and inter-annual precipitation found in the desert steppe. The study investigates the effects of different grazing durations on vegetation and soil properties of a desert steppe community. The experiment was conducted in Xisu Banner in Inner Mongolia with ifve treatments：CG （continuous grazing）, 40UG （40 d ungrazed）, 50UG （50 d ungrazed）, 60UG （60 d ungrazed） and UG （ungrazed）. The biomass of both shrub and annual-biennial plant communities were signiifcantly decreased by CG. Continuous grazing and 40UG signiifcantly reduced the ANPP （aboveground net primary productivity） by the end of the three year study. 60UG treatment increased soil organic carbon （OC）, total nitrogen concentration （TN） and total phosphorus concentration （TP） concentrations and 50UG increased the TN and total phosphorus concentration （TK） concentrations, whereas CG, 40UG and 50UG decreased soil OC, TP and available phosphorus concentration （AP） concentrations. The perennial plant species of the desert steppe were generally tolerant for grazing. The annual-biennial plant species had large variability in ANPP because of the inter-annual precipitation. Our results highlight that inter-annual precipitation variations could strongly modify the community responses to grazing in arid ecosystems.

关 键 词：ANPP plant species plant fimctional group soil nutrient 

分 类 号：S812[农业科学—草业科学]