Substantial contribution of trees outside forests to above-ground carbon across China
Abstract Accurately quantifying canopy height and above-ground carbon across diverse land-cover types is crucial for understanding carbon storage dynamics and guiding climate-mitigation strategies. Yet existing maps often overlook non-forest ecosystems. Here we present a deep learning framework based on a U-Net architecture that combines radar, optical, elevation and slope data to produce a 10 m canopy height map across China. The model is trained with laser measurements from NASA’s GEDI mission validated using unmanned aerial vehicle lidar data ( MAE = 2.39 m ). We then estimate the above-ground biomass and carbon from these heights using a Random Forest model ( MAE = 37.71 Mg ha-1 ). By deriving carbon from canopy height, we take advantage of U-Net’s ability to capture trees in non-forest ecosystems such as croplands, grasslands and urban areas. Our nationwide 30 m carbon map reveals that trees outside forests contribute 20.8-32.9% of China’s above-ground carbon in 2019 (3.62-5.72 Pg C), underscoring their importance.
Authors
- Martin Brandt (ORCID: https://orcid.org/0000-0001-9531-1239)
- Xiaowei Tong (ORCID: https://orcid.org/0000-0001-8057-7560)
- Tianqi Shi (ORCID: https://orcid.org/0000-0003-4815-4175)
- Yang Su (ORCID: https://orcid.org/0000-0002-8309-6196)
- W. Li
- Xianglin Zhang (ORCID: https://orcid.org/0000-0003-0792-4700)
- S. X. Du (ORCID: https://orcid.org/0000-0001-5247-5559)
- Alexandre d’Aspremont
- Siyu Liu
- Qinghua Guo
- K Cheng
- Philippe Ciais
- Ge Han
- Songchao Chen
- Shilong Piao
- Xin Ma
- Yidi Xu
Institutions
- University of Copenhagen (DK)
- Centre National de la Recherche Scientifique (FR)
- Zhejiang University of Science and Technology (CN)
- Université de Versailles Saint-Quentin-en-Yvelines (FR)
- Chinese Academy of Sciences (CN)
- Peking University (CN)
- AgroParisTech (FR)
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR)
- Université Paris-Saclay (FR)
- École Normale Supérieure - PSL (FR)
- Wuhan University (CN)
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (FR)
- École Normale Supérieure (BI)
- Institute of Subtropical Agriculture (CN)
- State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing (CN)
- Laboratoire des Sciences du Climat et de l'Environnement (FR)
- Institute of Tibetan Plateau Research (CN)
- Zhanjiang Experimental Station (CN)
- Zhejiang University (CN)
- Wuhan Institute of Technology (CN)
- Tsinghua University (CN)
Publication Details
- Journal
- Communications Earth & Environment
- Published
- 2026-02-05
- DOI
- https://doi.org/10.1038/s43247-025-03150-y
- Primary Topic
- Remote Sensing and LiDAR Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.00