CAREER: Role of Plant Nutrient Uptake in Forest Nutrient Retention and Carbon Sequestration: an Integrated Research, Teaching and Outreach Program

这个项目的重点是气候变化对北方森林的影响。许多研究评估了单一季节内气候变化对森林的影响，但很少研究跨季节的影响以及这些影响如何相互作用。季节性影响可能不同，它们可能以拮抗或协同的方式相互作用。例如，夏季土壤变暖可能会促进根系生长，但冬季变暖可能会增加冻融循环的频率，并损害植物根系。该项目的目标是确定冬季和生长期气候变化对北方阔叶林营养和碳吸收的相互作用。这将通过在新罕布什尔州哈伯德布鲁克实验森林和马萨诸塞州波士顿阿诺德植物园建立生态系统变暖实验和温室实验来实现。这些实验产生的数据将用于修改现有的生态系统尺度模型（PnET-BGC），以提高其预测生态系统养分保留和碳储量的能力。这种实验和建模的结合将提高我们对生长季节土壤温度升高和冬季更频繁的冻融循环的相互作用的理解，并可能改变我们对气候变化如何影响东北森林和其他温带生态系统的看法。这个CAREER项目将整合研究、教学和推广。特别是，25名高中教师将通过正式讲座和实地练习接受森林生态学方面的培训。十名高中生、十名本科生和两名研究生将进行动手实验室和实地实验。波士顿大学多达240名本科生将参加周末实地考察，以了解森林生态学并获得实地研究经验。总之，这些活动将提高科学素养，促进学生和高中教师对气候变化与生态过程之间关系的理解。此外，将建立一个新的枫糖浆生产商“Sap-Net”网络，以更好地了解气候变化如何影响枫糖浆的生产和质量。

This project is focused on climate change effects on northern forests. Many studies have evaluated the impacts of variation in climate on forests within a single season, but few have examined the impacts across seasons and how these impacts may interact. Seasonal impacts may differ, and they may interact in ways that are either antagonistic or synergistic. For example, soil warming in summer may increase root growth, but warming in winter may increase the frequency of freeze/thaw cycles and damage plant root systems. The goal of this project is to determine the interactive effects of winter and growing season climate change on nutrient and carbon uptake in northern hardwood forests. This will be accomplished by establishing an ecosystem warming experiment at Hubbard Brook Experimental Forest, NH, and a greenhouse experiment at the Arnold Arboretum in Boston, MA. Data generated from these experiments will be used to modify an existing ecosystem-scale model (PnET-BGC) to improve its ability to predict ecosystem nutrient retention and carbon storage. This combination of experimentation and modeling will improve our understanding of the interactive effects of increased soil temperatures in the growing season and more frequent freeze/thaw cycles in winter, and may transform our thinking of how climate change will affect northeastern forests and other temperate ecosystems.This CAREER project will integrate research, teaching, and outreach. In particular, twenty-five high school teachers will be trained in forest ecology through formal lectures and field exercises. Ten high school students, ten undergraduates, and two graduate students will perform the hands-on laboratory and field experiments. Up to 240 undergraduate students at Boston University will participate in weekend field trips to learn about forest ecology and gain field research experience. Together, these activities will enhance scientific literacy and foster an understanding of the relationship between variation in climate and ecological processes for both students and high school teachers. Additionally, a new 'Sap-Net' network of maple syrup producers will be established to gain a better understanding of how variation in climate influences maple syrup production and quality.