Response of soil biogeochemistry to freeze-thaw cycles and implications for the soil respiration-climate feedback: A process-oriented experimental approach

土壤生物地球化学对冻融循环的响应及其对土壤呼吸-气候反馈的影响：面向过程的实验方法

• 批准号: RGPIN-2015-03801
• 负责人: Rezanezhad, Fereidoun
• 金额: $ 1.46万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=634169
• 关键词: Response; soil; biogeochemistry; freeze; thaw

Freeze-thaw cycles represent a major climate forcing acting on soils at middle and high latitudes. Freezing and thawing of soils affect their physical properties, biogeochemical processes, microbial community, and carbon and nutrient budgets. Although research during the last few decades has revealed the large effects freeze-thaw cycles have on greenhouse gas emissions and chemical leaching from soils, the underlying hydrological, physical, geochemical and microbial mechanisms, and their mutual interactions, remain poorly understood. One reason is the paucity of time-series data that capture the relevant transport and reaction processes within the soil system during freeze-thaw cycles. As a consequence, we are currently seriously limited in our ability to predict the response of soil processes to changes in the frequency, magnitude and duration of freeze-thaw events driven by ongoing and future climate change. The central aim of this

冻融循环是影响中高纬度土壤的主要气候强迫。土壤的冻融影响其物理性质、土壤地球化学过程、微生物群落以及碳和养分收支。尽管过去几十年的研究揭示了冻融循环对温室气体排放和土壤化学沥滤的巨大影响，但对潜在的水文、物理、地球化学和微生物机制及其相互作用仍然知之甚少。原因之一是缺乏时间序列数据，捕捉相关的运输和反应过程中的土壤系统在冻融循环。因此，我们目前在预测土壤过程对当前和未来气候变化驱动的冻融事件的频率、幅度和持续时间变化的反应方面受到严重限制。其核心目标是