Can improving predictions of soil oxygen dynamics increase understanding of greenhouse gas hotspots and hot moments?

改进土壤氧动态的预测能否增加对温室气体热点和热点时刻的了解？

• 批准号: 1613325
• 负责人: Terrance Loecke
• 金额: $ 69.93万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-10-22 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1613325&HistoricalAwards=false
• 关键词: improving; predictions; soil; oxygen; dynamics

The amount of oxygen in a soil affects many ecosystem processes, including the release of greenhouse gases such as nitrous oxide, methane and carbon dioxide. However, soil oxygen concentrations are rarely directly measured in research projects because they are difficult and expensive to measure accurately. Better understanding of the controls over soil oxygen could help guide land restoration projects that result in a greater removal of greenhouse gases from the atmosphere. The new technologies and approaches proposed in this project could lower the cost and enable easier measurements of soil oxygen, which could help reduce the financial burden of reducing greenhouse gas emissions in the future. This project will add to the national scientific capacity through support of four early career scientists and the interdisciplinary training of a postdoctoral student. The scientists will also enhance undergraduate research experiences. An important broader impact will be a partnership among land managers and the scientists involved to develop a continuing education program aimed at providing opportunities for citizens to engage in climate-friendly projects for the restoration of local ecosystems.Soil oxygen concentrations are usually estimated using computer models based on soil properties that are easier to measure, particularly soil water contents. But measurements made in prior research indicate that directly measured soil oxygen levels differ considerably from modeled soil oxygen levels. In fact, current computer models cannot predict the rapid changes in soil oxygen that are observed in wetlands, where the production of greenhouse gases is particularly high compared to other types of ecosystems. Mismatches between models and measurements may occur because in actual ecosystems the emission of greenhouse gases may not be constant across space and time, but likely occur under specific environmental circumstances that are particularly difficult to identify and keep track of (called hot spots or hot moments). This project will measure emissions in relation to hot spots and moments along transects running from abandoned agricultural lands into adjacent creeks at an established research site near Dayton, Ohio. Success requires high-resolution measurements of soil oxygen concentrations in space and time. This is a major challenge, but if successful, the project will critically contribute to the assessment of greenhouse gas fluxes from local ecosystems, as well as their incorporation into large-scale climate models.

土壤中的氧气含量影响许多生态系统过程，包括一氧化二氮、甲烷和二氧化碳等温室气体的释放。然而，在研究项目中很少直接测量土壤氧浓度，因为精确测量它们既困难又昂贵。更好地了解对土壤氧的控制可以帮助指导土地恢复项目，从而从大气中更多地去除温室气体。在这个项目中提出的新技术和方法可以降低成本，使土壤氧的测量更容易，这可以帮助减轻未来减少温室气体排放的经济负担。该项目将通过支持四名早期职业科学家和一名博士后的跨学科培训来增加国家科学能力。这些科学家还将加强本科生的研究经验。一个重要的更广泛的影响将是在土地管理者和参与其中的科学家之间建立伙伴关系，制定一个继续教育计划，旨在为公民提供参与气候友好型项目的机会，以恢复当地的生态系统。土壤氧浓度通常是用计算机模型来估计的，这种模型是基于更容易测量的土壤特性，特别是土壤含水量。但是在先前的研究中进行的测量表明，直接测量的土壤氧水平与模拟的土壤氧水平有很大的不同。事实上，目前的计算机模型无法预测在湿地观测到的土壤氧的快速变化，与其他类型的生态系统相比，湿地产生的温室气体特别高。模型和测量值之间可能会出现不匹配，因为在实际的生态系统中，温室气体的排放在空间和时间上可能不是恒定的，而可能发生在特别难以识别和跟踪的特定环境情况下（称为热点或热点时刻）。该项目将在俄亥俄州代顿附近的一个已建立的研究地点测量热点和热点时刻的排放，这些热点和时刻从废弃的农业用地流向邻近的小溪。成功需要在空间和时间上对土壤氧浓度进行高分辨率测量。这是一项重大挑战，但如果成功，该项目将对评估当地生态系统的温室气体通量以及将其纳入大规模气候模型作出重大贡献。