Guo Haonan, Cui Shihao, Nielsen Claudia Kalla, Tang Lin, Pugliese Lorenzo, Wu Shubiao
Department of Agroecology, Aarhus University, Tjele 8830, Denmark.
Environ Sci Technol. 2025 Apr 8;59(13):6521-6533. doi: 10.1021/acs.est.4c12572. Epub 2025 Mar 27.
Rewetting drained peatlands is a promising strategy for mitigating carbon dioxide (CO) emissions, transforming these areas from carbon sources to sinks. Despite the well-known climate benefits, practical implementation is often hampered by conflicts between environmental goals and farmers' economic interests. Identifying optimal rewetting locations that maximize greenhouse gas (GHG) reduction while minimizing agricultural disruption is crucial to advancing this process. However, there is currently limited scientific evidence to guide these decisions. To identify "low-hanging fruits", 12 sites were selected for 4-month incubations to investigate the effects of four land uses (grass-cut, grass-graze, arable, and unmanaged) on CO and methane (CH) emissions postrewetting. Results showed that unmanaged sites exhibited the highest potential for GHG reduction (2015 mg CO-eq m day, 89.9%), followed by grass-graze, grass-cut, and arable sites, reflecting a gradient of management intensity. These insights suggest that prioritizing rewetting of unmanaged areas while delaying interventions on arable lands could yield greater climate benefits and enhance farmers' acceptance. Additionally, emission variability across sites was linked to soil properties, indicating that soils with a higher organic carbon content (for greater CO reduction) and lower bacterial diversity (for reduced CH production) offer the greatest GHG reduction potential. This study provides crucial scientific evidence to guide targeted peatland rewetting efforts, supporting net-zero emission goals.
重新湿润排水后的泥炭地是一种有前景的减缓二氧化碳（CO）排放的策略，可将这些地区从碳源转变为碳汇。尽管有众所周知的气候效益，但实际实施往往因环境目标与农民经济利益之间的冲突而受阻。确定最佳的重新湿润地点，在最大限度减少农业干扰的同时实现温室气体（GHG）减排最大化，对于推进这一进程至关重要。然而，目前指导这些决策的科学证据有限。为了找出“低垂的果实”，选择了12个地点进行为期4个月的孵化实验，以研究四种土地利用方式（割草、放牧、耕种和未管理）对重新湿润后CO和甲烷（CH）排放的影响。结果表明，未管理的地点温室气体减排潜力最高（2015毫克CO2当量/平方米·天，89.9%），其次是放牧、割草和耕种地点，这反映了管理强度的梯度。这些见解表明，优先对未管理区域进行重新湿润，同时推迟对耕地的干预，可能会带来更大的气候效益并提高农民的接受度。此外，各地点的排放变异性与土壤特性有关，这表明有机碳含量较高（以实现更大的CO减排）和细菌多样性较低（以减少CH产生）的土壤具有最大的温室气体减排潜力。本研究提供了关键的科学证据，以指导有针对性的泥炭地重新湿润工作，支持净零排放目标。
