This review focuses on the characteristics of soil dissolved organic carbon (DOC) and its response and potential mechanisms to climate warming. The properties of soil DOC are described, and its sampling and analyzing methods are summarized. Soil DOC is mainly derived from soil organic carbon (SOC) dissolution, root exudates, microbial products and necromass, and the concentration and composition of soil DOC varies along soil profile and over time. Multiple sampling (e.g. tension lysimeter) and analyzing (e.g. Fourier transform ion cyclotron resonance mass spectrometry) methods of soil DOC were applied to investigate the responses and mechanisms of soil DOC to experimental warming. Based on previous studies, this review also discussed the effects of plants, microorganisms, and soil properties on soil DOC characteristics. Experimental warming may not only directly alter soil DOC concentration, but also indirectly change soil DOC properties via affecting plant, soil and microbial properties. Future studies should pay more attention to the vertical transport and temporal dynamics of DOM to further improve the SOC models and strengthen the prediction accuracy of global carbon cycle under climate warming in future.

针对土壤溶解性有机碳(DOC)特性及其在气候变暖背景下的响应机制这一土壤碳循环研究的关键问题进行综述。首先阐述土壤 DOC的特性, 并总结其采集和测定方法。土壤DOC主要来源于土壤有机碳的溶解、植物根系和微生物分泌物与残体转化等过程, 其浓度和组成往往随土层深度和时间发生变化。多种采样方法(如负压法)与分析手段(如傅里叶变换离子共振回旋质谱仪)用于探讨土壤DOC对增温的响应及其机制。进一步梳理有关植物、微生物及土壤性质对土壤DOC特性的影响及其机制的文献, 认为增温不仅能直接改变土壤DOC的浓度, 还可以通过影响植物、微生物群落以及土壤理化性质等因素, 间接地改变土壤DOC的特性。未来的研究中应加强对土壤溶解性有机碳的土层迁移与时间动态的关注, 以便完善土壤碳模型, 提升未来气候变暖情景下全球碳循环过程变化的预测精度。