Collaborative RUI Proposal: Effects of Contrasting Cloud Regimes on Plant Carbon/Water Relations at Treeline

由于全球变暖导致的云模式的潜在变化至关重要，因为它们对植物群落所经历的阳光，温度和降水产生强烈影响。 植物对云量的变化特别敏感，因为阳光、温度和水的可用性是驱动光合碳增益、生长、繁殖和空间分布模式的重要因素。 对云模式变化的最显著反应预计是目前以频繁云层覆盖为特征的植物群落（例如山地云雾林、温带和热带雨林）。 该项目的目的是使用光合作用，水分胁迫，叶温，和生长的本地树种在南阿巴拉契亚山脉（美国东部）和落基山脉（美国西部）下的一系列自然发生的云制度的现场测量。根据这些数据，将开发一个模型，预测不断变化的云层覆盖模式对未来生长和生存的长期影响。 这些森林生态系统代表了地球仪上两种常见的山地云形态。分别是上午的浸云和下午的破云。 这些森林树种在生理上适应了当前的气候条件，预计云层覆盖的预测变化可能会导致水、阳光和叶温压力增加，最终导致地理和海拔迁移和/或灭绝。 这些高山森林的丧失或减少将对木材生产、积雪以及相应的农业和市政用水供应等重要特征产生重大影响。 该项目将涉及一所拥有强大研究生课程的大学（维克森林大学）和一所缺乏便利本科生研究的设施和设备的当地文理学院（高点大学）之间的合作努力。 来自HPU的三名本科生（来自科学界代表性不足的群体）致力于该项目，并非常积极地成为研究生。

Potential changes in cloud patterns due to global warming are of critical importance because of their strong influence on sunlight, temperature, and precipitation experienced by plant communities. Plants are especially sensitive to changes in cloud cover because sunlight, temperature, and water availability are important factors driving photosynthetic carbon gain, growth, reproduction, and spatial distribution patterns. The most dramatic response to changes in cloud patterns are projected for plant communities currently characterized by frequent cloud cover (e.g. mountain cloud forests, temperate and tropical rainforests). The purpose of this project is to use field measurements of photosynthesis, water stress, leaf temperature, and growth of native tree species in the Southern Appalachians Mountains (eastern US) and the Rocky Mountains (western US) under a range of naturally-occurring cloud regimes. From these data, a model will be developed that predicts long term effects of changing cloud-cover patterns on future growth and survival. These forest ecosystems represent two common types of mountain cloud regimes found across the globe?morning cloud-immersion and afternoon broken clouds, respectively. These forest tree species are physiologically adapted to their current climactic conditions, and it is anticipated that predicted changes in cloud cover may result in increased water, sunlight, and leaf temperature stress, leading ultimately to geographic and altitudinal migration, and/or extinction. Loss or decline of these high-mountain forests would have major impacts on such important features as timber production, snow accumulation, and corresponding water supply for agricultural and municipal use. This project will involve a collaborative effort between a university with a strong graduate program (Wake Forest University) and a local liberal arts college lacking the facilities and equipment to facilitate undergraduate research (High Point University). Three undergraduates from HPU (from underrepresented groups in science) have committed to the project and are highly motivated to become graduate students.