Grassland-Atmosphere Interactions: Analyses Using Coupled Ecophysiological, Ecosystem, Micrometeorology, and Mesoscale Atmospheric Models

草原-大气相互作用：使用耦合生态生理学、生态系统、微气象学和中尺度大气模型进行分析

• 批准号: 9524129
• 负责人: Michael Coughenour
• 金额: $ 25万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-09-15 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9524129&HistoricalAwards=false
• 关键词: Grassland; Atmosphere; Interactions; Analyses; Using

9524129 Coughenour This research is to develop capabilities for numerically assessing the responses of grassland ecosystems to atmospheric changes associated with increasing levels of greenhouse gases, particularly carbon dioxide (CO2). Currently, there are at least three major deficiencies in our abilities to perform these assessments. The first is a lack of computer models which have been calibrated and tested against field CO2 exposure experiments in grasslands. Accordingly, a focus of this research will be to collaborate with scientists working on an ongoing field exposure study in Kansas. An existing model of grassland ecosystem function and plant responses to CO2 and weather will be used for this purpose. Secondly, models that faithfully represent current understanding of plant physiology must be coupled with models that represent soil processes such as decomposition, nutrient cycling and water storage and flows to understand how whole ecosystems respond to atmospheric change. For example, it is possible that nutrient cycling rates will constrain otherwise positive plant growth responses to elevated CO2. Linked state-of-the-art plant physiological and soil process models will be employed in the proposed research. Thirdly, terrestrial ecosystem processes of water, carbon and energy exchange with the atmosphere have potentially significant effects on ecosystem responses to atmospheric change but have been poorly examined in past modeling research. This research will link ecological and atmospheric models to assess the role of atmospheric processes, particularly large-scale fluxes of water vapor and energy. These results will feedback onto plant growth through altered plant water use efficiency, and resultant responses of nutrient cycling rates. Grasslands, climate, and the interactions between climate and grasslands will be explored through linking these various models.

9524129 Coughenour这项研究是发展能力，数值评估草原生态系统的大气变化与温室气体，特别是二氧化碳（CO2）水平的增加。 目前，我们进行这些评估的能力至少存在三大缺陷。 首先是缺乏计算机模型，已校准和测试对现场CO2暴露在草原上的实验。 因此，这项研究的重点将是与正在堪萨斯进行实地接触研究的科学家合作。 现有的草地生态系统功能和植物对CO2和天气的响应模型将用于此目的。 其次，忠实地代表目前对植物生理学的理解的模型必须与代表土壤过程的模型相结合，如分解，养分循环和水的储存和流动，以了解整个生态系统如何应对大气变化。 例如，养分循环速率可能会限制植物对CO2浓度升高的积极生长反应。在拟议的研究中，将采用最先进的植物生理和土壤过程模型。 第三，陆地生态系统与大气的水、碳和能量交换过程对生态系统对大气变化的响应具有潜在的重要影响，但在过去的模拟研究中却没有得到充分的研究。 这项研究将把生态和大气模型联系起来，以评估大气过程的作用，特别是大规模的水蒸气和能量通量。 这些结果将通过改变植物水分利用效率以及由此产生的养分循环速率的反应反馈到植物生长上。 草原，气候，以及气候和草原之间的相互作用将通过这些不同的模型进行探讨。