Environmental and Physiological Regulation of Water Flux Through a Tropical Forest Ecosystem

热带森林生态系统水通量的环境和生理调节

• 批准号: 9419500
• 负责人: Frederick Meinzer
• 金额: $ 37.51万
• 依托单位: Hawaii Agriculture Research Center
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-15 至 2000-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9419500&HistoricalAwards=false
• 关键词: Environmental; Physiological; Regulation; Water; Flux

Meinzer 9419500 Transpiration, or evaporation of water from the leaves of plants, is a biological process that has a large impact on our physical environment through its effects on soil water storage, atmospheric water content, and the distribution of rainfall. Little is known about how plant species in tropical forests partition and regulate their use of soil water in time and space, yet such information is critical for predicting the effects of deforestation and climatic fluctuations on the water balance of tropical as well as temperate regions. The overall goal of this research is to determine how water movement along a continuum from the soil through plants to the atmosphere is regulated in contrasting types of tropical forest plants such as upper canopy trees, characteristic of mature forests, and forest gap colonizing plants, which may be representative of regrowth after harvest. The project will be carried out at three sites operated by the Smithsonian Tropical Research Institute in Panama. The relative roles of external environmental factors and inherent plant traits in the regulation of water use will be characterized. The research will provide unique, detailed information about how soil water resources in a seasonally dry environment are shared in time and space among different types of plants. General patterns that emerge will be applicable to temperate zone forests and other plant communities as well as tropical forests. The findings will contribute to our ability to predict how water use by vegetation at the stand and regional scales is influenced by species composition and should constitute a valuable contribution to the data necessary to make informed decisions in watershed management.

蒸腾作用，即植物叶片水分的蒸发，是一个生物过程，通过对土壤水分储存、大气含水量和降雨分布的影响，对我们的物理环境产生重大影响。关于热带森林中的植物物种如何在时间和空间上分配和调节其对土壤水分的利用，人们知之甚少，但这些信息对于预测森林砍伐和气候波动对热带和温带地区水分平衡的影响至关重要。本研究的总体目标是确定在不同类型的热带森林植物（如上冠树木、成熟森林的特征和林窗定殖植物）中，水分沿着从土壤到植物到大气的连续体运动是如何被调节的，这些植物可能是收获后再生的代表。该项目将在巴拿马史密森尼热带研究所经营的三个地点进行。分析了外部环境因子和植物内在性状在水分利用调控中的相对作用。这项研究将提供独特的、详细的信息，说明在季节性干旱环境中，不同类型的植物如何在时间和空间上共享土壤水资源。出现的一般模式将适用于温带森林和其他植物群落以及热带森林。这些发现将有助于我们预测林分和区域尺度上植被对水的利用如何受到物种组成的影响，并将对在流域管理中作出明智决策所必需的数据作出宝贵贡献。