Long-term drainage induces divergent changes of soil organic carbon contents but enhances microbial carbon accumulation in fen and bog

• Published in: Geoderma Vol. 404; p. 115343
• Main Authors: Liu, Chengzhu, Wang, Simin, Zhu, Erxiong, Jia, Juan, Zhao, Yunpeng, Feng, Xiaojuan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2021
• Subjects: Drainage; Microbial carbon pump; Neutral sugars; Soil fractionation; Wetland; Drainage; Microbial carbon pump; Neutral sugars; Wetland; Soil fractionation
• ISSN: 0016-7061; 1872-6259
• DOI: 10.1016/j.geoderma.2021.115343

•Long-term drainage induced divergent changes of SOC contents in fen and bog.•Both plant- and microbial-dominated soil fractions increased in drained fen.•Microbial sugars increased at the expense of plant sugars in drained bog.•Drainage enhanced soil “microbial carbon pump” both in fen and bog. Drainage-induced changes in wetland soil organic carbon (SOC) composition and origin are poorly investigated compared to SOC stocks. Here, using soil fractionation and neutral sugars, we find that long-term drainage increased both plant- and microbial-dominated (i.e., light and mineral-associated, respectively) fractions in a fen while microbial residues increased at the expense of plant residues in a drained bog, accompanied by divergent changes of SOC contents. These findings highlight stimulated soil “microbial carbon pump” in drained wetlands, whose efficiency deserves further investigation related to wetland SOC persistence.