呼图壁县NDVI变化与气候因子的响应.docVIP

呼图壁县NDVI变化与气候因子的响应 　　摘要：利用2010～2014年Landsat 8数据，通过差值和相关性分析法，对呼图壁县植被指数（NDVI）的时空演变进行分析，并对NDVI与气候因子相应的敏感性进行分析。结果表明，呼图壁县植被覆盖变化呈现明显的空间差异，植被指数有明显的地域特征，中部平原地区的NDVI最大，植被覆盖度明显较高，主要分布在林地、农田；南部的高山、丘陵及北部荒漠地区的NDVI较低，植被覆盖度也较低；呼图壁县具有明显的季节性NDVI变化，NDVI增加最快在夏季和秋季，而冬季增长缓慢，且NDVI对气候因子（降水、气温）响应存在时滞性；呼图壁县植被覆盖NDVI与降水和气温呈极显著相关关系，相关系数分别为0.843 1、0.870 2；复杂地形对植被指数有影响，农田耕作区的NDVI变化更大程度上体现了人类活动对植被指数的影响。随着人口增加、城市化进程加快、城乡建设侵占大量土地，会?p少植被覆盖的面积，影响植被指数的分布。 　　关键词：呼图壁县；植被指数；气候因子；Landsat 8 　　中图分类号：X144 文献标识码：A 文章编号：0439-8114（2016）20-5229-04 　　DOI：10.14088/j.cnki.issn0439-8114.2016.20.016 　　Abstract： Based on Landsat 8 data during 2010～2014，temporal and spatial evolution of NDVI and its relationship with climate factors in Hutubi county were analyzed by using difference and correlation analysis method. The results showed that Hutubi county was covered by the change showed significant spatial difference vegetation index with obvious regional characteristics. Central Hutubi vegetation condition was better than the northern and southern desert region of mountains，hilly areas，the distribution of woodland and fields，vegetation index was significantly higher. The NDVI developed faster in summer and autumn than that in winter，but the responses of vegetation variation to precipitation and temperature had time lag. There was significant relation between monthly average NDVI and monthiy precipitation and temperature（P0.01），with the corrlation coefficients 0.843 1 and 0.870 2. The impact of complex topography on vegetation indices，NDVI changes in agricultural farming area reflects the impact of human activities on vegetation indices greater extent. With population growth，urbanization，urban costruction occuied a lot of land， and it will reduce the area of the vegetation cover，vegetation index distribution influences. 　　Key words： Hutubi county； vegetation index； climate factor； Landsat 8 　　植被是地理环境的重要组成部分，植被的变化在全球变化研究中起着“指示器”的作用[1]。在植被覆盖变化研究中，归一化植被指数（NDVI，Normalized difference vegetation index） 能很好地反映植被覆盖、生物量及生态