毛乌素荒漠草原植被特征对降水变化的响应

荒漠草原植被特征对降水变化敏感,研究降水变化对荒漠草原植被特征影响具有重要的生态学意义.本研究以宁夏盐池县典型荒漠草原(毛乌素沙区农牧交错带)为研究对象,利用遮雨棚技术模拟正常降水的33％,66％,100％,133％ 和166％,在降水变化处理2年后,探讨荒漠草原植被特征对降水变化的响应规律.结果表明,增加降水使群落中...

Responses of Vegetation Characteristics of Mu Us Desert Steppe to Changes in Precipitation

Desert steppe vegetation characteristics are sensitive to precipitation changes,and researching the impact of precipitation changes on desert steppe vegetation characteristics has important ecological significance.This study took a typical desert grassland(agro-pastoral transition zone in the Mu Us sand area)of Yanchi County in Ningxia as the research object,and used canopy technology to simulate 33%,66%,100%,133%and 166%of normal precipitation.Two years later,the response law of vegetation characteristics of desert steppe to changes in precipitation was discussed.The results showed that increasing precipitation increased the proportion of important values of legumes and grasses in the community;treatment of 166%precipitation reduced the height of the community and the coverage of the community;the important value of the community and the dryness of the litter weight,biomass,and density first increased and then decreased with the increase of precipitation;height,coverage and Margalef index were extremely significantly negatively correlated;Pielou,Simpson,Shannon-wienner index and community density,litter dry weight,above ground and underground biomass showed a very significant negative correlation(P<0.05);the vegetation community under the treatment of natural precipitation was the most stable,and the similarity of the water-increasing treatment community was the least.This research aimed to explore the response strategies of desert grassland vegetation communities to changes in precipitation and provided a theoretical basis for grassland governance.