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地球的高分辨率天花板高度模型
Nico Lang1,2, Walter Jetz3, Konrad Schindler4
1EcoVision Lab, Photogrammetry and Remote Sensing, ETH Zürich, Zürich, Switzerland. nila@di.ku.dk.
Nature ecology & evolution
|September 28, 2023
概括
一张新的全球地图使用卫星数据显示了植被树冠的高度. 这种工具有助于理解生态系统,生物多样性和气候变化影响,突出了高层森林的保护需求.
科学领域:
- 生态生态学 生态生态学
- 遥感 遥感 遥感 遥感
- 地理空间科学 地理空间科学
背景情况:
- 植被高度变化对全球碳循环,生态系统功能和生物多样性至关重要.
- 准确,高分辨率的植被高度数据对于管理陆地生态系统,减缓气候变化和保护生物多样性至关重要.
研究的目的:
- 为2020年创建一个全面的10米分辨率的全球树冠高度地图.
- 开发一个融合卫星LiDAR和光学数据的模型,用于准确的树冠高度检索和不确定性量化.
主要方法:
- 开发了一个概率深度学习模型.
- 来自全球生态系统动态调查 (GEDI) 太空LiDAR任务的融合稀疏高度数据.
- 利用来自Sentinel-2的密集光学卫星图像进行全球覆盖.
主要成果:
- 在10米的地面采样距离生成了2020年全球树冠高度地图.
- 该模型改善了高高的天窗的检索,这些天窗储存了大量的碳.
- 全球只有5%的陆地拥有超过30米高的树木,其中34%位于保护区.
结论:
- 开发的树冠高度地图为生态系统管理和气候变化研究提供了关键数据.
- 该方法提高了对高层森林分布及其保护状况的理解.
- 这项工作支持森林保护工作,并推进气候,碳和生物多样性建模.
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