Rhizosphere priming describes a positive or negative change in the rate of soil organic matter decomposition caused by root activity and represents an important terrestrial soil–climate feedback. Few studies have investigated rhizosphere priming in wetlands, despite their disproportionate role in the global soil carbon budget. Here we present a literature analysis to show that both positive and negative rhizosphere priming can be much stronger in wetland than upland ecosystems. We argue that differences in plant–soil microbial interactions between dominantly oxic and anoxic soil environments induce the different degrees of rhizosphere priming effects. A conceptual framework is proposed in which wetland plants control soil redox status by acting as sources of both electron donors and acceptors, thereby influencing soil carbon stability through interactions with microbial communities. We identify key uncertainties in the mechanistic and quantitative understanding of wetland rhizosphere priming and demonstrate how priming could govern wetland soil carbon dynamics and ecosystem stability in response to climate change.

根际启动描述了根系活动引起的土壤有机质分解速率的正或负变化，代表了重要的陆地土壤-气候反馈。很少有研究调查湿地中的根际启动，尽管它们在全球土壤碳收支中的作用不成比例。在这里，我们进行了一项文献分析，以表明湿地中的正根际和负根际启动都比高地生态系统强得多。我们认为，占主导地位的含氧和缺氧土壤环境之间植物-土壤微生物相互作用的差异会诱发不同程度的根际启动效应。提出了一个概念框架，其中湿地植物通过充当电子供体和受体的来源来控制土壤氧化还原状态，从而通过与微生物群落的相互作用影响土壤碳稳定性。我们确定了湿地根际启动的机制和定量理解中的关键不确定性，并展示了启动如何控制湿地土壤碳动态和生态系统稳定性以响应气候变化。