npj Urban SustainabilityUrban forest canopy structural complexity is associated with carbon sequestration and optimization potential in BeijingKai ZhouShoubang HuangMengyu ShiJiyuan WangZhe LiuYaru ZhangShuyi YanHao YinXi Zheng2026-06-29Full textDOI https://doi.org/10.1038/s42949-026-00435-9