The soil carbon (C) stock, comprising soil organic C (SOC) and soil inorganic C (SIC) and being the largest reservoir of the terrestrial biosphere, is a critical part of the global C cycle. Soil has been a source of greenhouse gases (GHGs) since the dawn of settled agriculture about 10 millenia ago. Soils of agricultural ecosystems are depleted of their SOC stocks and the magnitude of depletion is greater in those prone to accelerated erosion by water and wind and other degradation processes. Adoption of judicious land use and science-based management practices can lead to re-carbonization of depleted soils and make them a sink for atmospheric C. Soils in humid climates have potential to increase storage of SOC and those in arid and semiarid climates have potential to store both SOC and SIC. Payments to land managers for sequestration of C in soil, based on credible measurement of changes in soil C stocks at farm or landscape levels, are also important for promoting adoption of recommended land use and management practices. In conjunction with a rapid and aggressive reduction in GHG emissions across all sectors of the economy, sequestration of C in soil (and vegetation) can be an important negative emissions method for limiting global warming to 1.5 or 2°C

This article is part of the theme issue ‘The role of soils in delivering Nature's Contributions to People’.

土壤碳 (C) 库由土壤有机碳 (SOC) 和土壤无机碳 (SIC) 组成，是陆地生物圈的最大库，是全球碳循环的关键部分。自大约 10 千年前定居农业出现以来，土壤一直是温室气体 (GHG) 的来源。农业生态系统土壤的 SOC 储量已耗尽，并且在易于被水、风和其他退化过程加速侵蚀的土壤中，其消耗程度更大。采用明智的土地利用和基于科学的管理实践可导致枯竭土壤重新碳化，使其成为大气 C 的汇。潮湿气候中的土壤有可能增加 SOC 的储存，而干旱和半干旱气候中的土壤有可能增加 SOC 的储存量。存储SOC和SIC。支付给土地管理者以在土壤中封存碳，基于对农场或景观水平土壤碳库变化的可信测量，对于促进采用推荐的土地利用和管理实践也很重要。与所有经济部门的温室气体排放量迅速而积极地减少相结合，土壤（和植被）中的碳封存可以成为将全球变暖限制在 1.5 或 2°C 的重要负排放方法

这篇文章是主题问题“土壤在为人类提供自然贡献方面的作用”的一部分。