贵州省植被NDVI时空演变特征及其对气温降水的响应

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摘要：本文基于MODIS NDVI 数据和贵州省19个气象站点的温度及降水数据，利用最大值合成法、趋势线分析法、空间插值、相关分析法等方法，分析了2001-2014年贵州地区植被NDVI在不同季节上时间和空间的变化以及温度、降水对植被覆盖的影响。结果表明：⑴从时间尺度上来讲，春季、秋季、生长季植被NDVI年际变化呈上升的趋势，夏季下降的趋势较弱。⑵从空间尺度上来讲，生长季植被覆盖整体趋于好的方向发展，局部地区植被退化。⑶植被覆盖均与气温、降水呈线性相关关系，夏季升温最快，其次是生长季，春季温度降低；秋季降水增加，春、夏、生长季降水减少。⑷不同季节NDVI值与降水量的相关性均大于NDVI与温度的相关性，降水量对贵州省植被覆盖度的影响更大。62652

毕业论文关键词：植被NDVI，时空变化，温度，降水，贵州省

Abstract: Based on MODIS NDVI data and meteorological data of 19 meteorological stations, the spatial-temporal variations of vegetation cover changes as well as the response of NDVI to the temperature and precipitation in Guizhou from 2001 to 2014 were analyzed by using the maximum synthesis, trend line analysis, spatial interpolation, correlation analysis and other methods. The results showed that: (1) At the time scales, the inter-annual change of vegetation NDVI in spring, autumn and the growing season showed an increasing trend, whereas the summer presented a relatively bit decreased trend. (2) At the spatial scales, the vegetation coverage trended to be a good direction, but some areas showed a reverse trend. (3) Vegetation coverage and temperature, precipitation showed a linear correlation. The rate of temperature increasing in summer was the fastest, and the growing season followed behind. The temperature in spring decreased, and the precipitation in spring, summer and the growing season reduced, while the precipitation in autumn increased. (4) The correlation coefficients between NDVI and precipitation in different seasons were greater than the correlation coefficients between NDVI and temperature. The precipitation is the key factor which affected the vegetation coverage in Guizhou province.

Keywords: NDVI, Spatial-temporal variation, Temperature, Precipitation, Guizhou Province

1 前言 4

2 研究区概况 4

3 数据来源与研究方法 5

3.1 数据来源与预处理 5

3.2 研究方法 7

4 结果与分析 8

4.1 贵州省植被NDVI时间变化趋势 8

4.2 贵州省植被NDVI空间变化趋势 9

4.3 植被NDVI与温度的年际关系 10

4.4 植被NDVI与降水量的年际关系 13

结论 15

参考文献 16

致谢 17

1 前言

植被作为陆地生态系统中的重要组成部分，其变化在环境和全球变化研究中起着敏感的指示作用［1］。植被的变化受人类活动及外部作用等多种因素的综合影响，其中气候因素中气温和降水被认为是影响植被变化的重要因素。植被指数是植被变化的重要指示参量，并且携带了大量地表植被的结构和功能信息。归一化植被指数(Normalized Different Vegetation Index，NDVI)能够精确地反映植被的光合作用强度、代谢强度以及年际变化特征，因此在全球范围内被广泛地应用到叶面积指数、生物量估算、植被动态监测、植被分类、土地利用变化和农作物长势及物候监测等研究中。目前，利用中分辨率成像光谱仪(MODIS)获取的植被指数已被广泛应用于植被的动态变化监测中[2-4]。它是在已有的AVHRR植被指数基础上改进设计的，空间分辨率比AVHRR和SPOT-VEGETATION数据高，获取周期要比TM数据短且连续，并且在一定程度上消除了大气、太阳高度角和云量等因素的影响，到目前为止已经积累了14年的有效数据，为植被的动态监测提供了可靠的手段。