Collaborative research: Linking Heterogeneity of Above-Ground and Subsurface Processes at the Gap-Canopy Patch Scales to Ecosystem Level Dynamics

树木通过根部吸收水分并将其散发到空气中来控制土壤湿度。它们还导致相反的效果，通过遮蔽地面和降低表面附近的风速来减少从土壤到空气的蒸发。目前的流域模型模拟土壤水分在区域尺度（数十至数百公里），并使用植被和土壤水分之间的相互作用的极其简化的表示。在这些模型中没有表现出个体树冠之间的差异和树冠结构的影响。该项目旨在提高对异质森林冠层中蒸发、蒸腾和土壤水分之间关系的理解，以及这些关系如何影响从树木尺度到生态系统和区域尺度的土壤水分异质性。该项目将利用密歇根大学生物站现有的丰富数据和正在进行的各种观测。将结合使用详细的观测和最先进的高分辨率建模工具。新的雷达为基础的体积观测土壤水分，并在树冠微气象测量将被使用，沿着与一个新的综合建模方法。该项目将提高我们预测生态系统结构在多个尺度上对能量、水和二氧化碳与大气的交换以及对区域分水岭功能的影响的能力。在气候变化和人类对森林干扰增加的情况下，这种进步尤其重要，因为预期这些情况会增加森林和其他重要自然资源的空间异质性。它还将创建一个建模工具，在水文和生态科学中具有真正的变革价值。俄亥俄州州立大学和密歇根大学的研究生将通过这一合作项目得到支持。本科生将从事拟议的研究。“植物和水”，一个教育K-12社区外展计划将被开发，以说明土壤-植物-大气连续体中水流的基本原理，并将培训和雇用本科生作为俄亥俄州中部大兄弟大姐妹住宅营地奥蒂奥克瓦的讲师，作为美国农业部林务局“更多孩子在树林里”倡议的一部分，一个针对俄亥俄州中部服务不足的小学年龄儿童的项目。

Trees control soil moisture by drawing water through the roots and transpiring them to the air. They also lead to an opposite effect of reducing evaporation from the soil to the air by shading the ground and reducing the wind speed near the surface. Current watershed models simulate soil moisture at regional scales (tens to hundreds of km) and use extremely simplified representations of the interactions between vegetation and soil moisture. The differences between individual crowns and the effects of the canopy structure are not represented in these models. This project aims to improve understanding of the relationships between evaporation, transpiration and soil moisture in heterogeneous forest canopies, and how these relationships affect soil moisture heterogeneity from the tree scale to the ecosystem and regional scales. The project will capitalize on the existing wealth of data and on-going diverse observations at the University of Michigan Biological Station. A combination of detailed observations and state-of-the-art high-resolution modeling tools will be used. Novel radar-based volumetric observation of soil moisture, and in and above canopy micrometeorological measurements will be used, along with a novel integrated modeling approach. The project will advance our capability to predict the effects of ecosystem structure at multiple scales on the exchanges of energy water and CO2 with the atmosphere, and on the functioning of the regional watershed. Such advancement is particularly important in conditions of changing climate and increased human disturbance to forests, which are expected to increase the spatial heterogeneity of forests and other important natural resources. It will also create a modeling tool that will have a truly transformative value in the hydrological and ecological sciences. Graduate students at Ohio State University and the University of Michigan will be supported through this collaborative project. Undergraduate students will be engaged in the proposed research. "Plant and Water", an educational K-12 community-outreach program will be developed to illustrate the underlying principles of water flow in soil-plant-atmosphere continuum and will train and employ undergraduate students as instructors at Big-Brothers Big-Sisters of Central Ohio Residental Camp Oty'Okwa, as part of the USDA Forest Service's "More Kids in the Woods" initiative, a program for underserved elementary-aged children within central Ohio.