Collaborative Research: Root Induced Changes of Soil Physical Properties Using Synchrotron X-ray Microtomography (CMT) and Micromechanical Simulations

合作研究：利用同步加速器 X 射线显微断层扫描 (CMT) 和微机械模拟根系引起的土壤物理性质变化

• 批准号: 0816726
• 负责人: Scott Tyler
• 金额: $ 10.91万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0816726&HistoricalAwards=false
• 关键词: Collaborative; Research; Root; Induced; Changes

The rhizosphere, the zone of soil immediately surrounding plant roots, plays a prominent role in supplying plants with water and nutrients. However, surprisingly little is known about rhizosphere physical properties and how they affect root growth, water and nutrient uptake. The lack of non-invasive and non-destructive imaging techniques necessary to observe living roots growing in undisturbed soil have been a main reason for this shortcoming. Recent advances in synchrotron X-ray microtomography, or CMT, provide the potential to directly observe soil physical properties around living roots in-situ. The goal of this research is to quantify rhizosphere physical properties by (1) employing CMT to visualize physical root-soil structure interactions, (2) using computer models to simulate root-induced structural alterations to the rhizosphere using micro-mechanical approaches, and (3) estimating changes in rhizosphere hydraulic properties, such as water retention and hydraulic conductivity, based on CMT imaging and inverse modeling.This research seeks to provide transformative insights into the role of rhizosphere physical properties for water and nutrient uptake by living plants. It serves as a stepping stone for better understanding the role of plants in the critical zone at the soil-atmosphere interface. The project cuts across disciplinary boundaries of biology, soil physics, and soil mechanics to offer new insights on surface runoff, soil compaction and erosion, losses to agricultural productivity, land reclamation, and principles of soil-plant interactions. Doctoral students and a post-Doctoral associate will be trained through this project.

根际，即植物根系周围的土壤区域，在为植物提供水分和养分方面起着重要作用。然而，令人惊讶的是，很少有人知道根际的物理特性，以及它们如何影响根系生长，水分和养分吸收。 缺乏非侵入性和非破坏性的成像技术来观察在原状土壤中生长的活根是造成这一缺点的主要原因。 同步辐射X射线显微层析成像技术（CMT）的最新进展为原位直接观察活根周围的土壤物理性质提供了可能。 本研究的目的是通过以下方式量化根际物理性质：（1）使用CMT可视化物理根-土结构相互作用，（2）使用计算机模型使用微观力学方法模拟根诱导的根际结构变化，（3）估计根际水力性质的变化，如保水性和水力传导性，基于CMT成像和逆向建模。这项研究旨在为活体植物吸收水分和养分的根际物理性质的作用提供变革性的见解。 它是更好地理解植物在土壤-大气界面临界区中的作用的垫脚石。 该项目跨越了生物学、土壤物理学和土壤力学的学科界限，为地表径流、土壤压实和侵蚀、农业生产力损失、土地复垦和土壤-植物相互作用原理提供了新的见解。博士生和一名博士后助理将通过该项目接受培训。