森林火灾前后植被覆盖对比分析

摘要：植被的恢复是森林火灾后生态环境修复的重要内容。本文使用Landsat8影像，通过比较归一化植被指数（NDVI）、归一化燃烧指数（NBR）的方法，分析比较了山东威海市环翠区仙姑顶景区在森林火灾发生后的植被变化以及恢复情况。结果表明：基于Landsat8影像，归一化植被指数、归一化燃烧指数均可用于森林火灾中植被过火区域的提取以及面积的估算；山东威海植被的覆盖度在自然生长的情况下，季节性明显，通常在8、9月份达到最大值，而在1、2月份达到最小值，在出现火灾等意外情况下，其植被的覆盖度明显的下降，但恢复过程中的植被覆盖度变化的总体趋势保持不变；燃烧区域越严重的地方植被覆盖度越低，植被的恢复情况就越差。66470

毕业论文关键词：归一化燃烧指数，归一化植被指数，Landsat8，森林火灾

Abstract: The restoration of vegetation was very important for the ecological environment after forest fire. In this paper, the vegetation change and recovery after a forest fires, occurred on the top of Xiangu, Huancui District, Weihai, Shandong, were analyzed briefly by comparing the normalized difference vegetation index and the normalized burn ratio respectively using the images of Landsat 8. The results showed that, based on landsat8 image, the normalized difference vegetation index, normalized burn ratio could be used for the extraction of forest fire vegetation burned region and estimation of the area of burned region. In the natural growth condition, the vegetation coverage in Xiangu had the obvious seasonal trend, usually reaching the maximum coverage in the August and September, and reaching the minimum coverage in the January and February. In case of fire accident, the vegetation coverage was significantly decreased, but the overall trend of the vegetation coverage variation remained unchanged in the process of the vegetation coverage recovery. Furthermore, the more serious the fire, the lower the vegetation coverage and the worse the vegetation recovery.

Keywords: NDVI, NBR, Landsat8, Forest fire

1 引言 6

2 研究区域介绍 7

3图像预处理与光谱运算 7

3.1图像预处理 7

3.2 图像光谱运算 10

4 结果与分析 11

4.1 时间变化 11

4.2 空间变化 14

总结 16

参考文献 17

致谢 19

1 引言

随着1972年Landsat1的发射[1]，人类对环境的监控进入一个新的阶段——遥感影像监控，由于其在时间和空间上具有广域覆盖能力，近几十年来已成为环境监测的主要方式之一。

2013年2月11号，NASA 成功发射了 Landsat 8 卫星，Landsat 8上主要携带了两个载荷：陆地成像仪（OLI）和热红外传感器（TIRS），本研究主要是利用OLI所包括的波段来检测火灾前后森林的植被覆盖度。OLI包括9个波段（见表1），空间分辨率为30米，其中包括一个15米的全色波段，成像宽幅为185x185km。论文网

表1 OLI传感器主要参数[12]

Landsat8 类型波长范围（微米）分辨率/米数据用途

Band1 蓝色波段森林火灾前后植被覆盖对比分析:http://www.751com.cn/shengwu/lunwen_74419.html