Guo Hongbo, Du Enzai, Terrer César, Jackson Robert B
State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China.
School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing, China.
Nat Commun. 2024 Jan 27;15(1):806. doi: 10.1038/s41467-024-44887-y.
Urban greenspaces continue to grow with global urbanization. The global distribution and stock of soil organic carbon (SOC) in urban greenspaces remain largely undescribed and missing in global carbon (C) budgets. Here, we synthesize data of 420 observations from 257 cities in 52 countries to evaluate the global pattern of surface SOC density (0-20 cm depth) in urban greenspaces. Surface SOC density in urban greenspaces increases significantly at higher latitudes and decreases significantly with higher mean annual temperature, stronger temperature and precipitation seasonality, as well as lower urban greenness index. By mapping surface SOC density using a random forest model, we estimate an average SOC density of 55.2 (51.9-58.6) Mg C ha and a SOC stock of 1.46 (1.37-1.54) Pg C in global urban greenspaces. Our findings present a comprehensive assessment of SOC in global urban greenspaces and provide a baseline for future urban soil C assessment under continuing urbanization.
随着全球城市化进程的推进，城市绿地面积持续增加。城市绿地中土壤有机碳（SOC）的全球分布和储量在很大程度上仍未得到描述，并且在全球碳（C）预算中缺失。在此，我们综合了来自52个国家257个城市的420个观测数据，以评估城市绿地中表层土壤有机碳密度（0 - 20厘米深度）的全球格局。城市绿地中的表层土壤有机碳密度在较高纬度地区显著增加，而随着年平均温度升高、温度和降水季节性增强以及城市绿化指数降低而显著降低。通过使用随机森林模型绘制表层土壤有机碳密度图，我们估计全球城市绿地的平均土壤有机碳密度为55.2（51.9 - 58.6）Mg C/ha，土壤有机碳储量为1.46（1.37 - 1.54）Pg C。我们的研究结果对全球城市绿地中的土壤有机碳进行了全面评估，并为持续城市化进程下未来城市土壤碳评估提供了基线。
