Molecular Biogeochemistry of Soil Organic Matter with Environmental Change

环境变化下土壤有机质的分子生物地球化学

• 批准号: RGPIN-2015-05760
• 负责人: Simpson, Myrna
• 金额: $ 3.64万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=665257
• 关键词: Molecular; Biogeochemistry; Soil; Organic; Matter

The proposed research program will employ an array of novel molecular tools that provide detailed information about soil organic matter (SOM) composition, biogeochemistry and ecosystem function. These tools, which have been pioneered by my research group, involve both targeted and non-targeted approaches using using mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy; arguably two of the most advanced structural techniques available in modern science. These techniques will be used to study the SOM in soil samples collected from several long-term field experiments in collaboration with University researchers in the United States. This program will also examine SOM mechanisms using innovative lab-based experiments.******SOM constitutes more than two-thirds of terrestrial carbon stocks yet current and predicted trends with respect to environmental change have resulted in uncertainties about the fate of soil carbon reserves. SOM biogeochemical cycling plays an integral role within the global carbon cycle through the regulation of atmospheric carbon dioxide via the intricate balance between supporting soil microbial respiration and plant photosynthesis. Previous research has hypothesized that SOM composition is highly sensitive to changes in moisture, temperature, atmospheric CO2 levels, and nitrogen deposition, as well as differences related to localized environmental conditions. For example, increases in atmospheric CO2 levels, increased nitrogen deposition, increased soil temperatures and increases in detrital deposition have all been hypothesized to alter soil biogeochemical processes. However, there is a gap in our understanding with respect to the mechanisms of SOM dynamics with long-term environmental change. As such, there is a desperate need to develop and use research tools that can detect shifts in SOM biogeochemistry at the molecular-level that improve the understanding of ecosystem-level responses to environmental change. ******The proposed research program will study the molecular biogeochemistry of SOM from long-term field sites that focus on soil warming, nitrogen deposition, and shifts in plant detrital inputs in forests. This information will be coupled with that from collaborating Universities and will enable a molecule to ecosystem, bottom-up understanding of SOM biogeochemistry and ecosystem-level responses to environmental change. The proposed research program will also examine SOM protection mechanisms using laboratory studies that employ innovative MS and NMR techniques. Trainees will develop highly desired skills via hands-on training with novel tools used to monitor SOM in the environment. Overall, this research program will identify environmental change impacts on soil carbon cycling and will shape new policies and environmental management practices to ensure the long-term sustainability of soil resources.**

拟议的研究计划将采用一系列新的分子工具，提供有关土壤有机质（SOM）组成，土壤地球化学和生态系统功能的详细信息。这些工具由我的研究小组开创，涉及使用质谱（MS）和核磁共振（NMR）光谱的靶向和非靶向方法;可以说是现代科学中最先进的两种结构技术。这些技术将用于研究与美国大学研究人员合作的几个长期田间实验中收集的土壤样品中的SOM。该计划还将使用创新的实验室实验来研究SOM机制。*土壤有机质占陆地碳储量的三分之二以上，但目前和预测的环境变化趋势导致土壤碳储量的命运不确定。土壤有机质的生物地球化学循环通过维持土壤微生物呼吸和植物光合作用之间的复杂平衡来调节大气中的二氧化碳，在全球碳循环中发挥着不可或缺的作用。以前的研究假设，SOM组成是高度敏感的水分，温度，大气中的CO2水平，氮沉降的变化，以及与本地化的环境条件的差异。例如，大气CO2水平的增加、氮沉降的增加、土壤温度的升高和碎屑沉降的增加都被认为会改变土壤的生态地球化学过程。然而，有一个差距，我们的理解与SOM动态机制与长期的环境变化。因此，迫切需要开发和使用能够在分子水平上检测SOM生物化学变化的研究工具，以提高对生态系统对环境变化的响应的理解。****** 拟议的研究计划将研究SOM的分子生物地球化学从长期的现场，重点是土壤变暖，氮沉降，并在森林植物碎屑输入的变化。这些信息将与合作大学的信息相结合，使分子能够进入生态系统，自下而上地了解SOM的地球化学和生态系统对环境变化的反应。拟议的研究计划还将使用采用创新MS和NMR技术的实验室研究来检查SOM保护机制。学员将通过使用用于监测环境中SOM的新工具进行实践培训来开发高度期望的技能。总的来说，这项研究计划将确定环境变化对土壤碳循环的影响，并将制定新的政策和环境管理实践，以确保土壤资源的长期可持续性。