Feng Xiaojuan, Zhao Yunpeng, Wang Houquan, Liu Chengzhu
State Key Laboratory of Forage Breeding-By-Design and Utilization and Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
China National Botanical Garden, Beijing, China.
Glob Chang Biol. 2025 Jun;31(6):e70300. doi: 10.1111/gcb.70300.
As a tremendous global carbon reservoir, wetlands play a pivotal role in mediating climate change. Organic carbon (OC) stored in wetlands is usually considered to be dominated by particulate organic carbon (POC) devoid of mineral protection. However, recent studies have revealed that reactive iron (Fe) (hydr)oxides are more abundant than previously recognized in wetlands and may stabilize up to 40% of soil organic carbon (SOC). Yet the significance of Fe-OC interactions in wetland carbon preservation and their responses to global changes remain insufficiently understood. Here this review summarizes recent advances in three key aspects related to Fe-OC interactions in wetlands: microbe- and plant-mediated biogeochemical processes regulating the formation and accumulation of reactive Fe (hydr)oxides in wetland soils; characteristics of Fe-OC interactions and their implications for wetland carbon preservation; and the response of Fe-OC interactions to global changes including drainage and warming. We also highlight future research directions and potential strategies related to wetland Fe-OC interactions, which warrant better recognition in the protection and restoration of wetland carbon reservoirs. These advances underscore that mineral protection by reactive metal oxides is an underappreciated mechanism of SOC preservation in wetlands, potentially improving our understanding of wetland carbon dynamics under global changes.
作为巨大的全球碳库，湿地在调节气候变化中起着关键作用。湿地中储存的有机碳（OC）通常被认为主要由缺乏矿物保护的颗粒有机碳（POC）组成。然而，最近的研究表明，活性铁（Fe）（氢）氧化物在湿地中的含量比以前认为的要丰富，并且可能稳定高达40%的土壤有机碳（SOC）。然而，Fe-OC相互作用在湿地碳保存中的重要性及其对全球变化的响应仍未得到充分理解。本文综述了湿地中与Fe-OC相互作用相关的三个关键方面的最新进展：微生物和植物介导的生物地球化学过程调节湿地土壤中活性Fe（氢）氧化物的形成和积累；Fe-OC相互作用的特征及其对湿地碳保存的影响；以及Fe-OC相互作用对包括排水和变暖在内的全球变化的响应。我们还强调了与湿地Fe-OC相互作用相关的未来研究方向和潜在策略，这些在湿地碳库的保护和恢复中值得更好地认识。这些进展强调，活性金属氧化物的矿物保护是湿地中SOC保存的一种未被充分认识的机制，可能会提高我们对全球变化下湿地碳动态的理解。
