Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado, USA.
Yale School of the Environment, New Haven, Connecticut, USA.
Glob Chang Biol. 2024 Jun;30(6):e17372. doi: 10.1111/gcb.17372.
Widespread adoption of regenerative agriculture practices is an integral part of the US plan to achieve net-zero greenhouse gas emissions by 2050. National incentives have particularly increased for the adoption of cover crops (CCs), which have presumably large carbon (C) sequestration potential. However, assessments of national CC climate benefits have not fully considered regional variability, changing C sequestration rates over time, and potential NO trade-offs. Using the DayCent soil biogeochemical model and current national survey data, we estimate CC climate change mitigation potential to be 39.0 ± 24.1 Mt COe year, which is 45%-65% lower than previous estimates, with large uncertainty attributed to NO impacts. Three-fourths of this climate change mitigation potential is concentrated in the North Central, Southern Great Plains and Lower Mississippi regions. Public investment should be focused in these regions to maximize CC climate benefits, but the national contribution of CC to emissions targets may be lower than previously anticipated.
普及再生农业实践是美国到 2050 年实现温室气体净零排放计划的一个组成部分。国家激励措施尤其增加了对覆盖作物（CC）的采用，这些作物可能具有很大的碳（C）固存潜力。然而，对国家 CC 气候效益的评估并未充分考虑区域变化、随时间变化的碳固存率以及潜在的权衡。我们使用 DayCent 土壤生物地球化学模型和当前的国家调查数据，估计 CC 气候变化缓解潜力为 39.0±24.1 Mt COe 年，比以前的估计低 45%-65%，其中不确定性主要归因于对氮氧化物的影响。这一气候变化缓解潜力的四分之三集中在中北部、南部大平原和密西西比河下游地区。公共投资应集中在这些地区，以最大限度地发挥 CC 的气候效益，但 CC 对排放目标的国家贡献可能低于先前预期。
