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: 1457505
• 负责人: Terrance Loecke
• 金额: $ 69.93万
• 依托单位: University of Nebraska-Lincoln
• 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: 2015-06-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1457505&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，因为它们难以精确测量且昂贵。更好地了解对土壤氧气的控制可以帮助指导土地恢复项目，从而从大气中去除更多的温室气体。 该项目提出的新技术和方法可以降低成本，使土壤氧的测量更加容易，这有助于减轻未来减少温室气体排放的财政负担。该项目将通过支持四名早期职业科学家和对一名博士后学生进行跨学科培训，增强国家的科学能力。科学家们还将增强本科生的研究经验。一个重要的更广泛的影响将是土地管理者和相关科学家之间的伙伴关系，以制定一个继续教育计划，旨在为公民提供机会，参与气候友好型项目，以恢复当地生态系统。土壤氧浓度通常是使用计算机模型估计的基础上，更容易测量的土壤特性，特别是土壤水分含量。但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差异。事实上，目前的计算机模型无法预测在湿地中观察到的土壤氧气的快速变化，与其他类型的生态系统相比，湿地的温室气体产量特别高。模型和测量之间可能出现不匹配，因为在实际生态系统中，温室气体的排放在空间和时间上可能不是恒定的，而是可能发生在特别难以识别和跟踪的特定环境条件下（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既定研究地点测量从废弃农田到邻近小溪的横断面沿着的热点和时刻的排放量。 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，该项目将为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做出重大贡献。