Collaborative Research: Restricted Plasticity of Canopy Stomatal Conductance: A Conceptual Basis for Simpler Spatial Models of Forest Transpiration

合作研究：冠层气孔导度的限制可塑性：更简单的森林蒸腾空间模型的概念基础

• 批准号: 0405381
• 负责人: Brent Ewers
• 金额: --
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0405381&HistoricalAwards=false
• 关键词: Collaborative; Research; Restricted; Plasticity; Canopy

0405381EwersIt is clear from recent reports by the water and carbon groups associated with the United States Global Change Research Program that accurate predictions of canopy stomatal conductance in forested systems are critical for the understanding of land surface - atmosphere fluxes and how they are affected by climate and land use changes. Indeed, land use changes are producing more fragmented landscapes and these are not readily represented in current land surface models. Current forest flux models were developed under the paradigm of research in which uniform forest stands are identified, flux measurements are made in the centers of these stands, and then what is learned here is extrapolated to the entire stand and beyond. This approach is neither necessary nor justified given the spatial complexity of vegetative communities. This projectseeks to develop a conceptual model of forest transpiration that embraces the inherent spatial variability of stomatal control while retaining a tractable measure of generalizability that is the hallmark of empirical models of stomatal conductance. Our conceptual model is based on the idea that canopy stomatal conductance is regulated primarily by water potential when water fluxes are high and of significant hydrologic import. We propose that species plasticity in canopy stomatal conductance, which determines its spatial variability and challenge for quantifying, follows a linear relationship that is keyed off of an easily quantifiable reference conductance0405381EwersIt is clear from recent reports by the water and carbon groups associated with the United States Global Change Research Program that accurate predictions of canopy stomatal conductance in forested systems are critical for the understanding of land surface - atmosphere fluxes and how they are affected by climate and land use changes. Indeed, land use changes are producing more fragmented landscapes and these are not readily represented in current land surface models. Current forest flux models were developed under the paradigm of research in which uniform forest stands are identified, flux measurements are made in the centers of these stands, and then what is learned here is extrapolated to the entire stand and beyond. This approach is neither necessary nor justified given the spatial complexity of vegetative communities. This projectseeks to develop a conceptual model of forest transpiration that embraces the inherent spatial variability of stomatal control while retaining a tractable measure of generalizability that is the hallmark of empirical models of stomatal conductance. Our conceptual model is based on the idea that canopy stomatal conductance is regulated primarily by water potential when water fluxes are high and of significant hydrologic import. We propose that species plasticity in canopy stomatal conductance, which determines its spatial variability and challenge for quantifying, follows a linear relationship that is keyed off of an easily quantifiable reference conductance

从与美国全球变化研究计划相关的水和碳群的最新报道中可以清楚地看出0405381WERESIT，该计划的准确预测森林系统中的冠层气孔电导对于理解土地表面 - 大气通量以及它们如何受到气候和土地利用变化的影响至关重要。实际上，土地利用变化正在产生更零散的景观，这些景观在当前的陆地表面模型中不容易代表。当前的森林通量模型是在确定统一森林林的研究范式下开发的，在这些林分的中心进行了通量测量，然后在这里学到的知识被推断到整个支架及以后。考虑到植物群落的空间复杂性，这种方法既不是必要的也不是合理的。该项目共同旨在开发一种森林蒸腾概念模型，该模型包含气孔控制的固有空间可变性，同时保留了可易于的普遍性度量，这是气孔电导的经验模型的标志。我们的概念模型是基于这样的想法：当水通量高并且具有重要的水文进口时，树冠气孔电导主要由水潜力调节。我们提出，冠层气孔电导中的物种可塑性决定了其空间可变性和量化的挑战，遵循线性关系，该关系是由易于量化的参考电导量从最新的报告中明确的。受气候和土地使用变化的影响。实际上，土地利用变化正在产生更零散的景观，这些景观在当前的陆地表面模型中不容易代表。当前的森林通量模型是在确定统一森林林的研究范式下开发的，在这些林分的中心进行了通量测量，然后在这里学到的知识被推断到整个支架及以后。考虑到植物群落的空间复杂性，这种方法既不是必要的也不是合理的。该项目共同旨在开发一种森林蒸腾概念模型，该模型包含气孔控制的固有空间可变性，同时保留了可易于的普遍性度量，这是气孔电导的经验模型的标志。我们的概念模型是基于这样的想法：当水通量高并且具有重要的水文进口时，树冠气孔电导主要由水潜力调节。我们提出，冠层气孔电导中的物种可塑性决定了其空间可变性和量化的挑战，遵循线性关系，该关系由易于量化的参考电导键关闭。