International Research Fellowship Program: Interactions between Plants, Herbivores and Natural Enemies along a Latitudinal Gradient of Australian Rainforests

国际研究奖学金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。该项目的奖项提供了联合研究的机会，并利用国外独特或互补的设施、专业知识和实验条件。该奖项将支持Lora A.Richards博士与澳大利亚悉尼麦格理大学的Mark Westoby博士合作的为期24个月的研究奖学金。食草动物受到食物资源和捕食者的共同限制。这些限制的相对重要性受到植物生产力的影响，植物生产力可能在几个空间尺度上有所不同。在全球范围内，生产率普遍向赤道方向增长。当大树倒下在雨林中形成光隙时，就会发生更局部规模的变化。这种对森林地面的新光照使植物生长迅速，与没有光照的森林地面相比，增加了林隙的生产力。这项研究正在使用生产率局部差异的结果来确定全球规模模式。利用这项技术，这项研究正在检验一种假设，即草食动物对热带雨林中的捕食更敏感，它们对温带雨林中的食物资源更敏感。这项研究正在比较节肢动物群落、植物质量和数量、草食率和捕食率的变化，以及随着光隙大小的增加而增加的植物生产力。与悉尼Maquarie大学的Mark Westoby合作，正在从澳大利亚东部从热带到温带的总共六个雨林地点收集数据。

0601921RichardsThe International Research Fellowship 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 research fellowship by Dr. Lora A. Richards to work with Dr. Mark Westoby at Macquarie University in Sydney, Australia.Herbivores are limited by a combination of food resources and predators. The relative importance of these limitations is influenced by plant productivity, which can vary at several spatial scales. On a global scale, productivity generally increases towards the equator. Variation on a much more local scale occurs when large trees fall in rainforests creating light gaps. This new light exposure to the forest floor causes plants to grow quickly increasing the productivity of the gap in comparison to the forest floor without a light gap. The study is using results from local variation in productivity to determine global scale patterns. Using this technique the study is testing the hypothesis that herbivores are more sensitive to predation in the tropical rainforests, and they are more sensitive to food resources in temperate rainforests. The study is comparing changes in arthropod communities, plant quality and quantity, herbivory rates and predation rates with increasing plant productivity as the light gap size increases. Data are being collected from a total of six rainforest sites ranging from tropic to temperate along eastern Australia in collaboration with Mark Westoby at the Maquarie University in Sydney.