毕业论文--1982—2006年华北地区植被覆盖时空变化特征研究.docVIP

题目：1982—2006年华北地区植被覆盖时空变化特征研究 1982—2006年华北地区植被覆盖时空变化特征研究 摘要：植被具有明显的地域分异特征和空间变化规律。本研究利用1982—2006年25年的GIMMS/NDVI数据结合GIS技术，并运用多种统计方法，分别从时间、空间两方面定量分析了华北地区植被覆盖水平地域变化规律。研究结果表明：（1）1982—2006年华北地区植被年内总体呈上升趋势，植被年内变化在7、8月份达到最大值，不同省份植被年内变化趋势略有差异，但总的来说，变化大致一致。（2）25年以来，华北地区植被总体上未见明显增大趋势，年际变化标准差为0.0145，表明25年来年际波动不大，稳定性好。（3）华北地区的植被变化存在明显的区域差异，植被覆盖率比较高的区域主要集中在京津地区。总的来说，华北地区的植被从京津地区向内蒙古北部、西部两个方向逐渐由植被明显改善向严重退化过渡。（4）华北地区的植被具有明显的空间分异规律，根据植被指数的变化规律，将华北地区植被覆盖分为三种类型：北京、天津、河北一带为植被上升区；内蒙古中西部为植被稳定区；山西和内蒙北部为植被下降区。（5）华北地区的植被覆盖变化和气候变化有密切的联系，具体表现为：在空间上，正相关远多于负相关；在时间上，随着降水和温度的增加，植被的NDVI值呈增加趋势。 关键词：NDVI；植被覆盖；华北地区；时空变化  Spatiotemporal Changes of Vegetation Coverage in North China from 1982 to 2003 Abstract: Vegetation coverage has obvious regional differentiation characteristics and spatial changes. Based on GIMMIS/NDVI data of 25 years from 1982 to 2006 and combined GIS with some statistical calculation methods, the paper studied spatiotemporal changes of level regional vegetation coverage in the North China. The results showed that: (1) the changes of vegetation coverage were increased during 1982 to 2006. Different provinces reach maximum vegetation in July or August within the year, there are slightly different among five provinces, but generally, changes are almost the same. (2) The vegetation has not obviously increased in recent 20 years. The Standard Deviation of inter-annual variation is 0.0145.So we can conclude that the vegetation coverage changes smoothly and there are no remarkable fluctuations. (3) Vegetation coverage, which distribute mainly in Tianjin city and Beijing city, has obvious regional differentiation characteristics in North China. Overall, from Beijing and Tianjin to north and west of Inner Mongolia, the vegetation gradually decreased from significantly improving to degeneration. (4) There has obvious space distribution differentiation in North China. Based on the spatial difference of SLOPE values, the North China was divided into four styles: Beijing，Tianjin, Hebei,