生物炭对滨海湿地盐碱土壤碳氮循环的影响

滨海湿地盐碱土壤在全球碳氮循环及调节气候变化中起着重要作用。环境友好型土壤改良剂生物炭（Biochar,BC）在缓解气候变化和促进农业可持续发展方面前景巨大。然而,现有研究多关注BC对滨海湿地盐碱土壤中温室气体排放及土壤氮素流失的影响,缺乏其对滨海湿地盐碱土壤碳氮循环的深入研究和系统总结。本文综合分析了施用BC对滨海湿地盐碱土壤植被碳库、有机碳库、有机碳矿化及生物固氮、硝化、反硝化、矿化、氨损失等碳氮循环过程的影响和可能机制。指出未来应关注长期野外研究,利用宏基因组等现代分子生物技术,阐明BC对土壤碳氮循环影响的分子生物学机制,以期为滨海湿地生态系统的修复与功能保育提供理论依据。

Effects of biochar amendment on carbon and nitrogen cycling in coastal saline soils: A review

Coastal saline-alkaline soil plays important roles in global carbon and nitrogen cycling and climate change regulation. Biochar (BC), as an eco-friendly soil amendment, shows a promising prospect in terms of alleviating climate change and promoting sustainable agricultural development. However, most of the previous studies focused on the influence of BC application on greenhouse gas emissions and nitrogen availability and loss in coastal saline-alkaline soil, but little information that comprehensively summarized the effect of BC on the soil carbon and nitrogen cycling is available. As a result, the objective of this review is to comprehensively summarize that: (1) The influences of BC on soil carbon pools (vegetation and soil organic carbon) and soil organic carbon mineralization in the coastal saline-alkaline soil; (2) The influences of BC on nitrogen cycling, including biological nitrogen fixation, nitrification, denitrification, nitrogen mineralization, and ammonia volatilization; (3) The underlying mechanisms responsible for the BC-regulated carbon and nitrogen cycling in the soil. At last, we also point out that more efforts should be paid to the investigation of long-term experiments in field circumstances in future, and the explanation of the microbial mechanisms underlying soil carbon and nitrogen cycling affected by BC application using modern molecular biotechnology (e.g., metagenomics). This review would provide useful information for maintaining health and function of the coastal soil ecosystem by incorporation of BC.