NSF Postdoctoral Fellowship in Biology FY 2010

这一行动为2010财年的NSF少数民族博士后研究奖学金提供资金。该研究金支持研究员在东道实验室的研究和培训计划，研究员还提出了扩大生物学参与的计划。该奖学金的研究和培训计划的标题为杰西卡L。Osuna是“一项关于皮农松从干旱胁迫到死亡的生理学研究。“这项研究有两个主办机构，新墨西哥州大学和洛斯阿拉莫斯国家实验室，和联合赞助商，威廉T。Pockman和Nate G.麦克道尔 最近的温暖干旱导致美国西南部的松树死亡率非常高。对这种死亡率的潜在机制的完整理解将允许准确预测其在其他地区，物种和时间段的发生。本研究通过测量不同干旱胁迫水平下的光合作用、呼吸作用、非结构性碳水化合物水平和树脂流动来研究自养碳收支，以测试碳饥饿是否是干旱诱导的皮农死亡率的原因。如果气孔导度的长期下降导致光合作用碳固定减少，就会发生碳饥饿，从而导致维持呼吸作用消耗碳水化合物库，这种呼吸作用会在干旱期间持续下去。由于皮农提供重要的生态系统服务，如减少洪水和侵蚀，隔离二氧化碳，并为野生动物和具有重要文化意义的植物提供栖息地，能否积极主动地采取可降低死亡率或其影响的管理战略，对本区域至关重要，并具有广泛的重大影响。 该研究通过在气候学家、生态生理学家和植物生理学家之间建立联系而跨越学科界限。培训目标包括学习使用新的可调谐二极管激光器测量碳同位素的歧视，同时与气体交换，以及用于测量碳预算的其他方面，而不是光合通量的技术。最后，正在开展教育外联活动，通过指导年轻的少数民族科学家和在本科生和研究生课程中客座讲课，促进生物学领域的多样性，从而使学生了解学术界的多样性。

This action funds an NSF Minority Postdoctoral Research Fellowship for FY 2010. The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Jessica L. Osuna is "A physiological study of the progression from drought stress to mortality in piñon pine." There are two host institutions for this research, the University of New Mexico and the Los Alamos National Laboratory, and joint sponsors, William T. Pockman and Nate G. McDowell. Recent warm droughts have caused very high piñon pine mortality rates in theSouthwestern USA. A complete understanding of the underlying mechanisms of this mortality would allow accurate prediction of its occurrence in other regions, species, and periods of time. This research investigates the autotrophic carbon budget via measurements of photosynthesis, respiration, non-structural carbohydrate levels, and resin flow under varying levels of drought stress to test whether carbon starvation is responsible for drought-induced piñon mortality. Carbon starvation occurs if a prolonged decrease in stomatalconductance leads to reduced photosynthetic carbon fixation, causing the depletion of carbohydrate pools by maintenance respiration which continues through a drought.Because piñons provide vital ecosystem services such as reducing floods and erosion,sequestering carbon dioxide, and providing habitat for wildlife and culturally significant plants, the ability to proactively adopt management strategies that could reduce mortality, or the effects thereof, is vital to the region and has a significant broader impact. The research crosses disciplinary boundaries by forming links between climatologists, ecophysiologists, and plant physiologists. Training objectives include learning to use the novel tunable diode laser to measure carbon isotope discrimination simultaneously with gas-exchange as well as techniques used for measuring aspects of the carbon budget other than photosynthetic fluxes. Finally, educational outreach is being conducted to promote diversity within biology through mentorship of younger minority scientists and by guest lecturing in undergraduate and graduate courses, thus exposing students to diversity in academia.