International Research Fellow Awards: Comparative Ecophysiology of Savanna and Forest Trees as a Key to Understanding the Dynamics of the Savanna-Forest Boundary

9803013 Hoffmann国际研究员奖励计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将支持William a . Hoffmann博士与Augusto C. Franco博士在巴西巴西利亚大学进行为期24个月的博士后研究访问。他们的工作将涉及稀树草原和森林树木的生态生理学的比较，这是理解稀树草原-森林边界动态的关键。本研究的目的是：测量热带稀树草原和森林物种在水分关系、叶级生理和分布模式方面的差异，以显示这两类物种各自特征的趋同进化；衡量分配模式与生态生理适应对稀树草原和森林物种性能差异的重要性；并确定哪些环境因素限制了热带草原和森林树木在热带草原-森林边界上的生长。他们将在塞拉多进行这项研究，塞拉多是一个占地200万公里的热带草原植被。弗兰科博士的专业领域是塞拉多地区木本植物生态学的生理基础。除了使用巴西利亚大学的设施外，霍夫曼博士还可以使用一个国家公园、三个生态保护区和两个研究站，所有这些都可以用于这类研究。* * *

9803013 Hoffmann The International Research Fellow Awards Program enables U.S. scientists and engineers to conduct three to twenty- four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four-month postdoctoral research visit by Dr. William A. Hoffmann to work with Dr. Augusto C. Franco at the Universidade de Brasilia in Brazil. Their work will involve the comparison of the ecophysiology of savanna and forest trees as a key to understanding the dynamics of the savanna-forest boundary. The objectives of this research are: to measure differences in water relations, leaf-level physiology, and distribution patterns between savanna and forest species to show convergent evolution of traits within each of these two groups of species; to measure the importance of allocation patterns versus ecophysiological adaptations to the differences in the performance of savanna and forest species; and to determine what environmental factors limit the growth of savanna and forest trees across the savanna- forest boundary. They will conduct this research within the cerrado, a savanna vegetation that occupies 2 million kilometers of Brazil. Dr. Franco's area of expertise is in the area of the physiological basis of woody plant ecology in the cerrado. In addition to working with the facilities of the University of Brasilia, Dr. Hoffmann will have access to a national park, three ecological reserves and two research stations, all of which are accessible for this type of research. ***