Nitrogen Fixation, Alkaloid Metabolism, and Defoliation: Interactions in the Bush Lupine, Lupinus Arboreus (Ecology)

在农业和自然生态系统中，固氮都是新氮的重要来源。本研究提出了对自然生态系统中固氮影响的调查-加利福尼亚沿海羽扇豆为主的草原。本研究将集中在两个方面：第一，植物间固定率的变化模式是什么？其次，落叶如何影响植物的固氮速率和生物碱水平？羽扇豆素合成生物碱，含氮毒素对脊椎动物和无脊椎食草动物都有效。由于生物碱含有氮，固氮速率也会影响生物碱的合成。另一方面，对叶片的损害会增加生物碱的浓度，这往往与氮的来源无关。本特利博士将参加加州大学戴维斯分校博德加海洋实验室（BML）在冬季/春假期间开设的生态学野外课程，这是戴维斯分校的秋季生态学研究生课程（由那里的生态学研究生课程开设），并为海岸和野外生态学课程的本科生提供咨询和建议。此外，她还将参加每周一次的研讨会项目和研究生系列研讨会。该项目进一步推进了VPW计划的目标，即(1)为女性提供在工程和NSF支持的科学学科中发展职业的机会；(2)通过为在工业、政府和学术机构工作的女性科学家和工程师提供更大的知名度，鼓励女性在科学和工程领域追求职业。通过鼓励妇女参与科学，这是对国家未来科学活力的宝贵投资。

Nitrogen fixation can be a very important source of new nitrogen in both agricultural and natural ecosystems. This study proposes an investigation of the impact of nitrogen fixation in a natural ecosystem---the lupine-dominated grassland of coastal California. The study will focus on two aspects of fixation: first, what is the pattern of variation in fixation rates among the plants? and second, how does defoliation impact on both nitrogen fixation rates and levels of alkaloids in the plants? Lupines synthesize alkaloids, nitrogen-containing toxins effective against both vertebrate and invertebrate herbiovores. Because alkaloids contain nitrogen, nitrogen fixation rates can affect alkaloid synthesis as well. On the other hand, damage to foliage can increase alkaloid concentrations, often independent on the source of nitrogen. Dr. Bentley will participate in a UC (Davis) ecology field course given at Bodega Marine Laboratory (BML) during the winter/ spring break, a Davis-based, fall-quarter graduate course in ecology (given by the Graduate Program in Ecology there) and provide counseling and advice to undergraduate students in the course in Coastal and Field Ecology. In addition she will participate in a weekly seminar program and graduate student seminar series. This project furthers VPW program objectives which are (1) to provide opportunities for women to advance their careers in engineering and in the disciplines of science supported by NSF and (2) to encourage women to pursue careers in science and engineering by providing greater visibility for women scientists and engineers employed in industry, government, and academic institutions. By encouraging the participation of women in science, it is a valuable investment in the Nation's future scientific vitality.