EAR-PF: Assessing the Potential for Enhanced Duration of Soil Carbon Storage via Anaerobic Microsites from the Plant Rhizosphere to Catchment Scale

EAR-PF：评估从植物根际到流域规模的厌氧微位点延长土壤碳储存持续时间的潜力

• 批准号: 1952802
• 负责人: Hannah Naughton
• 金额: $ 17.4万
• 依托单位: Naughton, Hannah Rose
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-10-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1952802&HistoricalAwards=false
• 关键词: EAR; PF; Assessing; Potential; Enhanced

Dr. Hannah Naughton has been granted an NSF EAR Postdoctoral Fellowship to study the impact of anoxic microsites on soil carbon cycling at the University of California, Berkeley, in collaboration with Lawrence Berkeley National Laboratory. Upland soils, e.g. a typical farm soil, are considered completely oxic and thus unlimited with respect to microbial carbon oxidation to the greenhouse gas, carbon dioxide. However, upland soils contain up to 85% anaerobic pore space that hinders respiration and potentially exacerbates the release of potent greenhouse gases like methane. The goals of this fellowship are to develop a statistical and geospatial model predicting 1) the extent, and 2) the carbon storage in these anaerobic microsites along a hillslope-to-floodplain hydrologic gradient in East River, Colorado. This project will develop a conceptual framework that could be used as a tool for land managers and scientists to better understand carbon dynamics in their soils using readily available, remotely sensed data, thus minimizing time- and money-intensive field soil sampling and characterization. Such a tool and the basic scientific knowledge generated through this work will improve prediction and management of soil carbon storage under changing precipitation, temperature and vegetation going into the future, with extensions to calculating carbon credits, deciding between conventional and sustainable farming techniques, and better constraining countries’ terrestrial carbon emissions. This project will support women and other minority groups in the Earth Sciences through direct mentorship, campus and field site outreach discussing the uncommonly known diversity of (and in) soils, and through course development and teaching at UC Berkeley. Saturated conditions and organic inputs, two conditions that naturally vary along hillslope gradients, are known to deplete soil oxygen, but the role of roots in forming soil redox microheterogeneity has not yet been tested. Plant functional types (PFTs, e.g. shrub vs. grass) are adapted to landscape positions according to geomorphic and geologic controls on solar radiation, water and nutrient availability. Below-ground, PFTs differ significantly in root traits and role in soil aggregate formation. Previous East River work has demonstrated that PFT distribution is predictable based on remotely sensed surface and subsurface properties, suggesting soil redox microheterogeneity that controls carbon transformation may be predictable over larger scales. Using the hillslope-to-floodplain gradient, I propose to evaluate the relationship between landscape features, PFT distribution, soil physical characteristics, and microbial metabolism, and then determine the consequences for soil carbon composition and storage. These relationships will inform a geospatial model utilizing LiDAR and hyperspectral data to predict anaerobic microsite formation and resulting carbon storage potential. Mentoring and teaching opportunities and the scope of this project will prepare Dr. Naughton for a faculty position in an undergraduate-oriented college where she intends to continue studying the influence of micro-scale soil heterogeneity on carbon cycling and the means to predict and represent this knowledge over larger spatial scales.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Hannah Naughton 博士获得了 NSF EAR 博士后奖学金，与劳伦斯伯克利国家实验室合作，在加州大学伯克利分校研究缺氧微场地对土壤碳循环的影响。 高地土壤，例如典型的农场土壤被认为是完全含氧的，因此微生物碳氧化为温室气体二氧化碳的能力是不受限制的。 然而，高地土壤含有高达 85% 的厌氧孔隙空间，会阻碍呼吸，并可能加剧甲烷等强效温室气体的释放。 该奖学金的目标是开发一个统计和地理空间模型，预测 1) 范围和 2) 科罗拉多州东河沿山坡到洪泛区水文梯度的这些厌氧微场地的碳储存。 该项目将开发一个概念框架，可作为土地管理者和科学家的工具，利用现成的遥感数据更好地了解土壤中的碳动态，从而最大限度地减少时间和金钱密集型的实地土壤采样和表征。 这样的工具和通过这项工作产生的基础科学知识将改善未来降水、温度和植被变化下土壤碳储存的预测和管理，并扩展到计算碳信用额、在传统农业技术和可持续农业技术之间做出决定，以及更好地限制各国的陆地碳排放。 该项目将通过直接指导、校园和现场外展，讨论土壤（和土壤中）罕见的多样性，以及通过加州大学伯克利分校的课程开发和教学，支持地球科学领域的妇女和其他少数群体。 已知饱和条件和有机输入这两种沿着山坡梯度自然变化的条件会消耗土壤氧，但根系在形成土壤氧化还原微异质性中的作用尚未得到测试。 植物功能类型（PFT，例如灌木与草）根据对太阳辐射、水和养分可用性的地貌和地质控制来适应景观位置。 在地下，PFT 的根系特征和在土壤团聚体形成中的作用存在显着差异。 之前的东河工作已经证明，PFT 分布是可以根据遥感的地表和地下特性进行预测的，这表明控制碳转化的土壤氧化还原微异质性在更大的尺度上是可以预测的。 我建议利用山坡到洪泛区的梯度来评估景观特征、PFT 分布、土壤物理特征和微生物代谢之间的关系，然后确定对土壤碳组成和储存的影响。 这些关系将为利用激光雷达和高光谱数据的地理空间模型提供信息，以预测厌氧微位点的形成和由此产生的碳储存潜力。 指导和教学机会以及该项目的范围将为 Naughton 博士在一所本科院校的教职做好准备，她打算继续研究微观尺度土壤异质性对碳循环的影响，以及在更大空间尺度上预测和表示这些知识的方法。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的评估进行评估，被认为值得支持。 影响审查标准。