气候变化和人类活动对锡林郭勒草原植被覆盖度的影响

Effects of climate and human activities on vegetation cover changes in Xilingol steppe

基于遥感、气象及统计数据,采用线性趋势法和残差分析法,在不同时空尺度上监测1982-2018年锡林郭勒草原草地植被覆盖度动态,量化气候变化和人类活动对植被变化的贡献率。结果表明:1982-2018年,锡林郭勒草原植被覆盖度及变化具有明显的空间异质性,草甸草原覆盖度呈显著增加趋势(P<0.01),荒漠草原覆盖度呈显著减少趋势(P<0.01)。2000年为旗县草地覆盖度变化的主要节点。人类活动是锡林郭勒草原植被动态的主导因素,研究区多年人类活动因素的综合贡献率为65.06%。中东部和南部部分区域植被在人类积极作用下得到了显著改善,但西部和北部荒漠草原区的植被仍然呈现退化趋势。建议加大荒漠草原区生态政策实施力度以保障草地生态系统的可持续性。

This study used linear and residual analysis of remote sensing and meteorological data to monitor changes in fractional vegetation cover(FVC)in different banners from 1982 to 2018.Additionally,the relationship between climate change,human activities,and FVC change was determined,and then,the temporal and spatial pattern of the contribution rate of the two factors was quantified.The change in FVC in Xilingol steppe had evident spatial heterogeneity.In terms of grassland type,the FVC of meadow steppe increased significantly,while that of desert steppe decreased significantly.The FVC in the west and north areas showed a decreasing trend,while that in the east and south showed an increasing trend,with the year 2000 being the significant change node.FVC was positively correlated with precipitation(P<0.01).The spatial pattern of the impact of human activities on the FVC was different before and after 2000,and human activities from 1982 to2018 were the dominant explanatory factors.