Collaborative research: Restricted plasticity of canopy stomatal conductance: A conceptual basis for simpler models of forest transpiration

0405306 MacKayOur建议的项目有显着的智力价值，因为它明确地解决了水文学面临的两个关键问题。第一个问题是关于气孔控制水通量的对立观点，一种观点认为是碳同化控制，另一种观点认为是环境控制。我们的概念模型结合了这两个观点在一个unifiedmechanistic框架，结合了同化和水势控制蒸腾。我们的概念模型所解决的第二个问题是倾向于支持复杂的，经常是数学不适定的冠层模型，而不是简单的，可验证的。我们明确地解决这个基本问题，在水文建模中，使用一种新的，面向对象的冠层模型，可以灵活地调整其结构和机制，以提供的数据。通过调整模型的空间复杂性，我们将获得物种的可塑性和限制其跨越空间梯度的深刻见解，从而提供了一个严格的方法来测试我们的概念模型在我们的研究地点在北方威斯康星州。从我们提出的研究所获得的知识有广泛的影响，陆地表面modeling努力寻求产生全球变化对水循环的影响的准确预测。通过发展我们的概念模型，我们将能够提供一个相对简单的，但可移植的和科学上可辩护的模型。这些模式是制定和实施可信的州、联邦和国际政策的重要基础，这些政策旨在减轻或以其他方式适应预期的全球变化的后果。该项目的教育重点是多方面的。首先，我们将寻求额外的资金和其他手段的支持，咨询和培训来自北方威斯康星州的经济落后地区的本科生的综合团队，使用这个项目作为他们在威斯康星大学麦迪逊分校森林生态学教育的主要背景。此外，在与NSF研究合作网络项目，题为“契瓜梅贡生态系统-大气研究”，其中麦凯是一个核心项目的参与者，我们将举行一个全国性的宣传讲习班多尺度冠层通量测量和建模。PI将继续在我们各自的领域招募和雇用少数民族和其他代表性不足的学生。

0405306MacKayOur proposed project has significant intellectual merit because it explicitly addresses two keyproblems facing hydrology. The first problem concerns the opposing views of stomatal control ofwater fluxes, with one perspective assuming carbon assimilation control, and the other assumingan environmental control. Our conceptual model combines both of these perspectives in a unifiedmechanistic framework that combines both assimilation and water potential controls ontranspiration. The second problem addressed by our conceptual model is the tendency towardsfavoring complex and often mathematically ill-posed canopy models over simpler, verifiableones. We explicitly address this fundamental issue in hydrologic modeling by using a novel,object-oriented canopy model that can flexibly adjust its structure and mechanisms to the data itis provided. By adjusting model complexity spatially we will gain deep insights on speciesplasticity and restrictions thereof across spatial gradients, thus providing a rigorous approach totesting our conceptual model within our study site in northern Wisconsin.The knowledge gained from our proposed research has broad implications for land surfacemodeling efforts seeking to generate accurate predictions of global change effects on watercycling. By developing our conceptual model we will be able to provide a relatively simple, buttransportable and scientifically defensible model. Such models are essential foundations for thecreation and implementation of credible state, federal and international policies aimed atmitigating or otherwise adjusting to the consequences of anticipated global change. Theeducational emphasis of this project is multi-faceted. First, we will seek additional funding andother means of supporting, advising and training an integrated team of undergraduate studentsfrom the economically disadvantaged region of Northern Wisconsin, using this project as theprincipal context for their education in Forest Ecology at UW-Madison. Also, in connection withthe NSF Research Collaboration Network project entitled "Chequamegon Ecosystem-Atmosphere Study," for which Mackay is a core project participant, we will hold a nationallyadvertised workshop on multi-scale canopy flux measurements and modeling. The PIs willcontinue to recruit and hire minorities and other underrepresented students in our respectivefields.