Investigating carbon and nitrogen: interactions in perennial systems on marginal land

研究碳和氮：边际土地上多年生系统的相互作用

• 批准号: RGPIN-2018-04346
• 负责人: Oelbermann, Maren
• 金额: $ 2.91万
• 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: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=712919
• 关键词: Investigating; carbon; nitrogen; interactions; perennial

Land-use change and reliance on fossil fuels have decoupled carbon (C) and nitrogen (N) cycles, contributing to the accumulation of greenhouse gases (GHG) in the atmosphere. In a changing global environment with increased climate variability, maintaining agricultural productivity and reducing our reliance of fossil fuels remains a challenge. Using bioenergy crops is an innovative approach to address this challenge. Although ~15% of global energy production is currently derived from biomass, it is projected to account for 50% of global renewable energy sources by the year 2050. First generation bioenergy crops, derived from food crops such as corn, or the production of bioenergy crops on prime agricultural land solely is not ecologically sustainable and threatens global food security. This can be addressed by establishing perennial, or second generation, bioenergy crop systems (PBCS) on marginal land. Perennial bioenergy crops exploit and recycle nutrients through an extensive root system building soil C reserves and decreasing GHG emissions. However, this potential has not yet been well quantified and the mechanisms of interaction that regulate soil C and N dynamics in PBCS remains unexplored. This research program provides new knowledge on the long-term assimilation of C and characterizes temporal GHG emissions in fertilized and unfertilized PBCS on marginal land. It will also address the impact of freeze-thaw cycle (FTC) duration and temperature on GHG emissions and C and N dynamics. The methodological approach involves temporal GHG sampling and includes rigorous soil sampling and analysis. Investigating the interactions between GHG emissions and soil C and N dynamics concurrently enhances our understanding of PBCS management. This will also help advance our knowledge on the C sequestration and GHG emission potential of PBCS on marginal land. This information is essential when assessing the climate neutrality of PBCS and their potential incorporation into a carbon credit, or cap and trade program.

土地利用变化和对化石燃料的依赖导致碳 (C) 和氮 (N) 循环脱钩，导致大气中温室气体 (GHG) 的积累。在气候变化加剧的全球环境不断变化的情况下，保持农业生产力并减少对化石燃料的依赖仍然是一项挑战。使用生物能源作物是应对这一挑战的创新方法。尽管目前全球能源生产的约 15% 来自生物质，但预计到 2050 年，生物质将占全球可再生能源的 50%。第一代生物能源作物（源自玉米等粮食作物）或仅在优质农田生产生物能源作物在生态上不可持续，并威胁全球粮食安全。这可以通过在边际土地上建立多年生或第二代生物能源作物系统（PBCS）来解决。多年生生物能源作物通过广泛的根系开发和回收养分，建立土壤碳储备并减少温室气体排放。然而，这种潜力尚未得到很好的量化，并且调节 PBCS 中土壤碳和氮动态的相互作用机制仍有待探索。该研究项目提供了关于碳的长期同化的新知识，并描述了边际土地上施肥和未施肥的 PBCS 的暂时温室气体排放特征。它还将解决冻融循环 (FTC) 持续时间和温度对温室气体排放以及碳和氮动态的影响。该方法涉及时间温室气体采样，并包括严格的土壤采样和分析。研究温室气体排放与土壤碳氮动态之间的相互作用同时增强了我们对 PBCS 管理的理解。这也将有助于增进我们对边际土地上 PBCS 的碳封存和温室气体排放潜力的了解。在评估 PBCS 的气候中和性及其纳入碳信用额或总量控制与交易计划的可能性时，这些信息至关重要。