内蒙古荒漠草原东部植被指标动态变化及其与气候变化的关系

本研究以内蒙古荒漠草原东部的苏尼特右旗为研究区域，利用2003—2013年草原植被高度、覆盖度、鲜草和干草产量等植被指标动态变化数据，结合水热等重要气候因子，分析了区域植被指标时空动态变化与气候因子变化趋势，并对植被指标动态变化与气候变化最佳模型进行评价与筛选。结果表明，该区域气温和降水量整体呈“冷干化”趋势，植被覆盖度、高度、草产量与降水量呈正相关关系，与气温呈负相关关系；降水量对荒漠草原植被影响更大。植被年最大高度、覆盖度、草产量与水热因子存在时滞效应。植被高度、鲜草产量、干草产量与水热因子最优拟合模型均为二项式模型，植被覆盖度与水热因子最优拟合模型为幂指数模型。

Dynamic Changes of Vegetation Indexes and Their Relations with Climate Changes in the Eastern Desert Steppe of Inner Mongolia

Sunite Right Banner located in the eastern part of Inner Mongolia desert steppe was taken as the research area of this paper.Steppe vegetation height,coverage,the fresh grass yield,hay yield and other vegetation indicators dynamic change data from 2003 to 2013 were used,combined with important climatic factors such as precipitation and temperature.The temporal and spatial dynamic changes of regional vegetation index and the changing trends of climatic factors were analyzed,and the best models of vegetation index dynamic changes and climate change were evaluated and screened.The results showed that the overall temperature and precipitation in this area showed a“cold-drying”trend.The vegetation coverage,height,and grass yield were positively correlated with precipitation,while negatively correlated with temperature.Precipitation had a greater impact on vegetation in the desert steppe.There was a time lag effects between the annual maximum height,coverage,grass yield and precipitation and temperature factors.The best fitting model for vegetation height,fresh grass yield,hay yield and temperature and precipitation factors was a binomial model,and the best fitting model for vegetation coverage and temperature and precipitation factors was a power exponential model.