1982年至2016年的全球土地变化
Xiao-Peng Song1, Matthew C Hansen2, Stephen V Stehman3
1Department of Geographical Sciences, University of Maryland, College Park, MD, USA. xpsong@umd.edu.
Nature
|August 10, 2018
概括
在1982年至2016年间,全球树木覆盖率增加了7.1%,尽管热带地区的森林砍伐, 这种土地变化会影响气候和生态系统服务.
科学领域:
- 地球系统科学
- 环境科学
- 遥感技术
背景情况:
- 土地使用和土地覆盖面的变化对全球环境动态,包括气候和生态系统服务产生重大影响.
- 之前的全球土地变化量化有限,阻碍了对这些动态的全面理解.
- 土地变化既是全球环境变化的驱动因素,也是其结果,
研究的目的:
- 使用卫星数据提供1982年至2016年全球土地变化动态的全面量化记录.
- 分析全球树木覆盖,赤裸地面和其他土地覆盖类型的净变化.
- 将土地变化归因于直接的人类活动而非气候变化等间接因素.
主要方法:
- 分析了35年的卫星数据以绘制全球土地变化动态.
- 量化土地覆盖类型的变化,包括树木覆盖和赤裸的地面.
- 将观察到的土地变化归因于直接的人类活动和间接环境驱动因素.
主要成果:
- 在1982年至2016年期间,全球树木覆盖面增加了7.1% (224万平方公里),热带地区的增长超过了热带地区的损失.
- 全球裸露面积减少了3.1% (160万平方公里),特别是在亚洲农业地区.
- 60%的土地变化与直接的人类活动有关,
结论:
- 在过去的35年里, 全球树木覆盖率呈现出净增长.
- 土地使用的变化在区域上是多样化的,有显著的热带森林砍伐,温带森林再生和城市化.
- 开发的数据集为改善土地利用变化,生物地化学循环和植被气候相互作用的模型提供了有价值的见解.
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