Leaf Hydrophobicity and Canopy Storage Relationships of Common Species in Semi-Arid Environments of the Western United States

美国西部半干旱环境中常见物种的叶片疏水性与冠层储存关系

• 批准号: 0961474
• 负责人: Curtis Holder
• 金额: $ 9.78万
• 依托单位: University of Colorado at Colorado Springs
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2011-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0961474&HistoricalAwards=false
• 关键词: Leaf; Hydrophobicity; Canopy; Storage; Relationships

The repellency of a water droplet by a leaf surface (i.e., leaf hydrophobicity) is a common adaptation among plant species in habitats exposed to daily precipitation. Leaf hydrophobicity may be an important variable that influences canopy storage capacity during a rainfall event. Canopy storage capacity is the amount of water held by the canopy during a rainfall event before water starts to drip as indirect throughfall. Species with highly repellent leaf surfaces may increase the quantities of throughfall at a site and result in greater hydrological inputs beneath the canopy. Professor Curtis Holder in the Department of Geography and Environmental Studies at the University of Colorado at Colorado Springs will examine the extent to which leaf hydrophobicity influences canopy storage capacity in common species of the semi-arid Western United States. Specifically, the three objectives of this project are to determine if leaf hydrophobicity and canopy storage capacity differs between species with contrasting leaf habits and growth forms, to compare methodologies that calculate leaf hydrophobicity and canopy storage capacity, and to determine if leaf hydrophobicity influences canopy storage capacity on a leaf area basis. To address these three objectives, the investigator will measure canopy storage capacity by a mass-balance approach with rainfall simulation and an immersion method. Additionally, the investigator will measure leaf hydrophobicity by calculating the contact angle between a water droplet and the leaf surface using a digital camera and goniometer. Canopy characteristics (leaf and woody area, leaf orientation, and leaf surface properties) of each species will also be determined. If differences in leaf hydrophobicity and canopy storage capacity between species are significant, then hydrological inputs to a watershed may be significantly influenced by vegetation changes. Within this context, this project will increase our understanding of hydrological processes and inform the planning and management of vegetation cover in watersheds contributing as raw water source regions for municipalities. This project will enhance our understanding of hydrologic fluxes within watersheds by examining the significance of leaf hydrophobicity as a mechanism that influences canopy storage capacity. By measuring leaf hydrophobicity and canopy storage capacity of common species within a watershed, this project will provide information on the significance of leaf hydrophobicity in forest hydrology models that could enhance our understanding of the delivery of water resources from municipal watersheds. Several undergraduate and graduate students will receive valuable educational opportunities by participating directly in field data collection during this project.

叶表面对水滴的排斥性（即，叶片疏水性）是暴露于每日降水的生境中的植物物种之间的常见适应。 叶片疏水性可能是一个重要的变量，影响冠层存储能力在降雨事件。 冠层储水量是降雨过程中，在水开始以间接穿透雨形式滴落之前，冠层所容纳的水量。 具有高度排斥性的叶表面的物种可能会增加在一个网站的穿透雨的数量，并导致更大的水文输入下的树冠。 位于科罗拉多斯普林斯的科罗拉多大学地理与环境研究系的柯蒂斯保持器教授将研究叶片疏水性对美国西部半干旱地区常见物种冠层储存能力的影响程度。 具体而言，该项目的三个目标是确定叶片的疏水性和冠层存储能力不同的物种与对比的叶片的习惯和生长形式，比较方法，计算叶片的疏水性和冠层存储能力，并确定如果叶片的疏水性影响冠层存储能力的叶面积的基础上。 为了解决这三个目标，调查员将测量冠层存储容量的质量平衡方法与降雨模拟和浸泡方法。 此外，研究人员将通过使用数码相机和测角仪计算水滴与叶片表面之间的接触角来测量叶片的疏水性。还将确定每个物种的冠层特征（叶和木本面积、叶方向和叶表面特性）。 如果物种之间的叶疏水性和冠层存储能力的差异是显着的，那么水文输入到流域可能会显着影响植被的变化。 在此背景下，该项目将增加我们对水文过程的了解，并为规划和管理作为城市原水水源区的流域植被提供信息。 本计画将借由研究叶片疏水性作为影响冠层储水量的一种机制的重要性，增进我们对集水区水文通量的了解。 通过测量叶疏水性和冠层存储能力的常见物种在流域内，该项目将提供信息的重要性，叶疏水性在森林水文模型，可以提高我们的理解，从城市流域的水资源输送。 一些本科生和研究生将通过直接参与本项目期间的现场数据收集获得宝贵的教育机会。