陕北沙漠化逆转区气温变化特征及其影响因素——以陕西榆林市为例

选取陕北沙漠化逆转区榆林作为研究对象，采用气候倾向率、Mann—Kendall非参数检验和小波分析法等气候诊断方法，探讨了1971年-2010年榆林地区气温时空分布规律、变化趋势及其影响因素。结果表明：榆林南北两大地貌单元气温逐年升高，北部增温幅度大于南部，气候倾向率关系为：陕南〈关中〈全国〈南部丘陵沟壑区〈北部风沙草滩区；南部丘陵沟壑区气温突变（1989年）早于北部风沙草滩区（1994年）。气温增加幅度存在差异，空间格局呈现“冷快暖l陧，整体一致增加”的变化特征。榆林地区气温变化完全符合全球变化规律，其驱动力是自然因素和人类活动共同作用的结果，太阳辐射由强到弱，加之LaNina事件频发，在一定程度上减缓了人类活动带来的增温。

The Characteristics of Temperature Changes in Desertification Reversal Region in Northern Shaanxi and Their Influencing Factors: A case study in Yulin, Shaanxi Province

The"Three North Shelterbelt Program"and"Grain-for-Green Project"carried out by the governments are dominant contributors to the severity reversal of desertification in north china.Climate change and human activities can decrease the desertification severity to some extent on the one hand but on the other hand they can remarkably affect the increase in desertification extent.In order to clarify the causes of rehabilitation in an agro-pastoral transitional zone of northern Shaanxi,this paper,based on the meteorological data from the 12 stations(1971-2010)in Yulin region,has analyzed the fundamental characteristics,temporal-spatial distribution and reasons of the temperature change in the desertification reversal region.Methods of linear regression,Mann-Kendall mutation test,wavelet analysis,kriging interpolation and other Climate diagnosis methods have been used.The results show that:the temperature increment in the northern region of Yulin is larger than that in the southern region;as for climate inclination rate,the south of Qinling mountains(0.121℃/10a)