1982—2015年新疆地区植被生长对气温的响应

基于1982-2015年归一化植被指数(NDVI)数据集、植被类型和气象数据,采用滑动偏相关分析、线性趋势分析和GIS空间分析方法,揭示了新疆地区生长季植被对气温响应的变化特征.结果表明:研究期间,在整个生长季,新疆地区植被活动对气温变化的响应强度呈现明显的降低趋势;季节尺度上,这种响应关系的变化趋势在夏、秋两季较为明显,春季植被活动对气温变化响应的变化趋势与之相反.在整个生长季,不同类型植被对气温变化的响应呈现减弱态势;在春季,草地和森林对气温变化的响应呈现显著增强趋势,而灌丛和荒漠对气温变化的响应趋势正好相反;在夏季,4种植被(草地、灌丛、荒漠、森林)对气温变化的响应均呈现显著降低趋势;在秋季,4种植被对气温变化的响应均没有显著的统计学特征.新疆地区生长季气温对植被的影响力减弱具有区域的普遍性特征,这可能与研究区降雨和太阳辐射活动变化的有关.

Responses of vegetation growth to temperature during 1982-2015 in Xinjiang,China.

Combined with the normalized difference vegetation index (NDVI) dataset, vegetation type data, and meteorological data, we revealed the variation of vegetation growth responses to air temperature in the growing-season during 1982-2015 in Xinjiang, using the moving-windows based partial correlation analysis, the unitary linear regression analysis and GIS spatial analysis. Results showed that, in the whole growing-seasons of study period, there was a significant downturn trend in the responses of vegetation growth to temperature. At the seasonal scale, the downturn trend was obvious especially in summer and autumn, while it was in adverse in spring. During the whole gro-wing season, the responses of different vegetation types to air temperature change showed a decreasing trend. Seasonally, the responses of grassland and forest to temperature change showed a significant increase, while that of shrubland and desert were exactly the opposite in spring. The responses of all natural vegetation (grassland, shrubland, desert and forest) to temperature change showed a significant decreasing trend in summer, whereas their responses in autumn had no significant statistical characteristics. Spatially, the decreasing influence of temperature on the vegetation growth during the growing season in Xinjiang was universal, which might be due to the change in precipitation and solar radiation.