基于多时相Landsat5/8影像的岷江汶川-都江堰段植被覆盖动态监测

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 基于多时相Landsat5/8影像的岷江汶川-都江堰段植被覆盖动态监测 DOI: 10.5846/stxb201409051756 作者: 作者单位: 西南土地资源评价与监测教育部重点实验室,西南土地资源评价与监测教育部重点实验室,西南土地资源评价与监测教育部重点实验室,西南土地资源评价与监测教育部重点实验室,西南土地资源评价与监测教育部重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金资助项目(41371125) Dynamic monitoring of fractional vegetation cover along Minjiang River from Wenchuan County to Dujiangyan City using multi-temporal landsat 5 and 8 images Author: Affiliation: Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu,Sichuan,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu,Sichuan,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu,Sichuan,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu,Sichuan,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu,Sichuan Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:植被覆盖度是衡量地表植被状况和指示生态环境变化的一个重要指标。基于像元二分模型,利用Landsat5/8遥感影像和DEM数据,对岷江汶川-都江堰段植被覆盖动态变化进行了监测,并结合高程、坡度和坡向数据,分析了汶川地震前后植被受损与恢复的空间动态格局变化。研究表明:植被覆盖总体良好,大部分区域的植被覆盖度均在中、高度以上,空间格局上呈现由汶川县东部、都江堰市西北部的龙门山区向两侧减少的总体趋势;地震造成植被受损面积达63808.7 hm2,且集中分布于海拔567-4331 m、坡度26-51°的范围以及东坡、北坡、南坡和西坡;震后5a,植被恢复面积17786.47 hm2,主要分布在海拔576-2180 m与3256-3793 m、坡度小于9°和26-51°以及东坡、东南坡和和南坡;高程和坡度对植被损毁与恢复的影响明显高于坡向。 Abstract:The terrestrial ecosystem plays an important role in maintaining the structure, function, and environment of earth systems, and therefore, human survival. Fractional vegetation cover (FVC) is an important indicator of ecological changes in the environment, and an important spatial parameter of land surface vegetation status for various ecological models. It is very important to estimate the changes and patterns of FVC within the fragile ecological system of the Minjiang River, which is located in a transition zone between the Tibetan Plateau and Sichuan basin. FVC information in the arid valley of the Minjiang River was extracted from remote sensing data, DEM, and GIS technology following the dimidiate pixel model. The differentiation characteristics of the spatial and temporal dynamic patterns of FVC, vegetation damage caused by the Wenchuan earthquake, vegetation restoration, elevation, slope, and aspect were also quantitatively studied. The results showed that:(1) the vegetation coverage was generally good during the study period; there were variations in levels of FVC, and the FVC in most areas was above medium and high levels. The overall spatial pattern showed reduced FVC on either side of the Longmen Mountains, in eastern Wenchuan County, and northwestern Dujiangyan City. The FVC change tended to increase first, then decrease with increasing elevation rendering. Above the lower levels, FVC was mainly distributed at elevations of 4331-4869 m, where the FVC decreased with increasing slope. More than 24% of the vegetation coverage was distributed in the area where the slope was less than 9°; there was little or no vegetation coverage in areas where the slope was greater than 51°. The FVC also changed according to aspect. It was mainly distributed on the eastern, western, and southern slopes. (2) The area of vegetation damage caused by the Wenchuan earthquake was 63808.7 hm2. Severe damage to vegetation occurred mainly within the range of 567-4331 m elevation, on slopes of 26-51°, with eastern, northern, southern, or western aspects. (3) After five years of natural regeneration, 17786.47 hm2 of the destroyed areas were recovered. The recovered vegetation area occurred mainly across elevation ranges of 567-2180 m and 3256-3793 m, on slopes of <9° or 26-51°, and eastern, southeastern, and southern aspects. (4) The results also showed that elevation and slope had significantly larger effects than aspect on vegetation damage or restoration. Although there was a certain correlation between the vegetation damage and restoration, the change patterns were complicated. The results provided very useful information for decision-making and policy-planning in the region of the Minjiang River, from Wenchuan County to Dujiangyan City, after the Wenchuan earthquake. Although the natural vegetation recovery is a slow process, some of the areas with earthquake-induced damage can be restored to their original condition through natural succession. Human intervention may not be a good way to address natural vegetation recovery in this area. Thus, vegetation restoration mainly involves closing the areas to promote natural vegetation restoration, or adopting artificial forestation to restore vegetation in a small area. 参考文献 相似文献 引证文献