Doctoral Dissertation Research: Effects of Forest Fragment Size, Shape, and Structure on Rainfall Redistribution and Solute Flux in Urban Settings

本博士论文研究项目将探讨城市森林碎片的形状和结构特征如何影响大都市地区树木繁茂的生态系统中的水和溶质循环。 博士生将寻求解开森林碎片化和生态系统服务之间的复杂关系，他们可以通过建立一个更清晰的理解不同的树冠结构和位置沿沿着城市到农村的土地利用梯度的森林碎片之间的水和溶质通量的差异提供。 本项目将增进对降水在福尔斯落入森林片断时所分配的形式的基本知识，例如在森林树冠中被截留的水、从树叶落到地面的福尔斯水（穿透雨）以及沿植物树干和茎干流下的水（茎流）。 项目的研究结果应有助于评估穿透雨和茎流的化学成分与碎片大小和形状、位置和结构特征的关系。 通过这些和其他测量，该项目将有助于更准确地量化城市森林片段提供的生态系统服务，特别是减少雨水径流和改变溶质向地下水和地表水的迁移。 除了加强基本的了解外，该项目还将为城市化地区的绿色/森林空间的保护提供管理森林碎片方法的新见解。这项工作的数据将通过特拉华州环境监测和分析中心的门户网站随时向公众提供，供那些有兴趣改善城市绿色空间管理的人使用。 作为博士论文研究改进奖，该奖项还将提供支持，使有前途的学生能够建立一个强大的独立研究生涯。这项研究的首要问题是：城市森林片断的水文功能（即降水分为穿透雨和树干茎流，以及溶质的淋溶和循环）在城市内的森林碎片之间以及沿着城乡梯度变化？ 这个学生将调查五个森林片段在威尔明顿，特拉华州，和沿着城市到农村的梯度在大都市地区的截留损失，以了解其对水的输入和穿透水和树干径流的化学特征的影响。 她将采用森林水文学和水化学实验室分析的实地方法来量化降雨分配和穿透雨和茎流的溶质化学。 进一步的分析将阐明降水分配在空间和时间上与土地利用有关的动态性质。

This doctoral dissertation research project will investigate the ways in which the shape and structural characteristics of urban forest fragments affect the cycling of water and solutes in wooded ecosystems of metropolitan areas. The doctoral student will seek to disentangle the complex relationship between forest fragmentation and the ecosystem services they can provide by establishing a clearer understanding of the differences in water and solute flux among forest fragments with varying canopy structure and location along an urban-to-rural land-use gradient. This project will enhance basic knowledge of the forms into which precipitation is partitioned when it falls in forest fragments, such as water that is intercepted in forest canopies, water that falls to the ground from leaves (throughfall), and water that flows down the trunks and stems of plants (stemflow). Project findings should help assess the chemistry of throughfall and stemflow in relation to fragment size and shape, location, and structural characteristics. Through these and other measurements, this project will help develop a more accurate quantification of ecosystem services provided by urban forest fragments, particularly the reduction of stormwater runoff and the modification of solute transport to ground- and surface-water pools. In addition to enhancing basic understanding, the project will provide new insights into methods to manage forest fragments for the conservation of green/forested space in urbanizing areas. Data from this work will be made readily available to the public via the Delaware Environmental Monitoring and Analysis Center web portal for those interested in improving the management of urban green spaces. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.The overarching question of this research is: How does the hydrological function of urban forest fragments (namely the partitioning of precipitation into throughfall and stemflow, and the leaching and cycling of solutes) vary among forest fragments within the city and along an urban-rural gradient? This student will investigate interception losses in five forest fragments in Wilmington, Delaware, and along an urban-to-rural gradient in that metropolitan area in order to understand its effect on water inputs and the chemical signature of throughfall and stemflow. She will employ field methods in forest hydrology and hydrochemical laboratory analyses to quantify both precipitation partitioning and solute chemistry of throughfall and stemflow. Additional analyses will elucidate the dynamic nature of precipitation partitioning over space and through time in relation to land use.