Through using Terra/MODIS NDVI data products and corresponding temperature and precipitation data during the period of 2000—2013,this study was to explore the spatio-temporal variation of vegetation during growing-season and its correlation with climatic factors in YRSR by linear regression analysis and correlation analysis. The results showed that multi-year averaged NDVI in YRSR during growing season presented significant regional variation,decreasing from southeast to northwest. The increasing trend of NDVI indicated YRSR vegetation tended to be improving during 2000—2013( P<0 . 01 ). Regions with insignificant NVDI changes were distributed widely in and covered 69. 58% of the area of YRSR. Regions with significant NDVI increaseing covered 28. 88%of the area of YRSR and concentrated in the northeastern YRSR and the area around Zaling and Eling lakes. Regions with significant NDVI decrease only covered 1 . 54% of the area of YRSR and distributed patchily in the upstream areas of Zaling and Eling lakes. Regions with significantly positive relationship between NDVI and climate factors during growing season concided with regions with increasing NDVI ,which indicated the warming and the wetting promoted vegetation growth in YRSR,and precipitation was a dominant driving factor. The maximum time lag periods of both temperature and precipitation affecting vegetation growth in YRSR were 16 or 32 days,but temperature had significantly same period effect upon the vegetation growth in YRSR.%为掌握黄河源区植被变化趋势及其与气候因子的关系,本研究利用2000—2013年Terra/MODIS NDVI数据和同期气温、降水资料,通过一元线性回归分析、相关分析等方法,对黄河源区生长季植被时空变化及其与气候因子进行关联分析.结果表明:黄河源区多年平均生长季NDVI整体表现为由东南向西北递减.2000—2013年,黄河源区生长季NDVI呈波动上升趋势(P<0.01);生长季各期NDVI均在增加,其中生长季初期NDVI增加较显著.近十几年NDVI无显著变化区域占黄河源植被覆盖区面积的69.58%,分布广泛;极显著和显著增加区域占28.88%,集中在黄河源东北部、扎陵湖和鄂陵湖周围;极显著和显著减少区域仅占1.54%,主要以小斑块状分布在扎陵湖、鄂陵湖以上源头区.生长季NDVI与气候因子显著正相关区域和NDVI增加区域高度一致,意味着黄河源区暖湿化促进了植被生长,而降水是影响黄河源区植被生长的主导因子.气温和降水对黄河源区植被生长影响的最大时间滞后效应约为16天或32天,且气温对黄河源区植被生长的影响还具有显著的同期效应.
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