Ecological Processes Influencing Local Biodiversity in Species-rich Pine Savanna Groundcover

美国东南部的松树稀树草原是世界上多样性最高的植物群落之一。它们有不连续的树冠，通常只有一个树种(长叶松)，地面植被层包含许多种类的草、草本和灌木。在1-1000平方米的小空间尺度上，松树稀树草原通常包含50-200多种开花植物。此外，超过25%的植物区系出现在地球上其他任何地方。保护松树稀树草原作为高度多样性的中心，需要了解治理生态机制。开发了一个概念模型来解释这种植物群落中的高度多样性。为了验证该模型的关键预测，一项涉及火灾操纵、火灾后营养物质、种子传播和植物之间竞争性相互作用的大型实验将运行三年，超过两个不同的火灾周期。实验结果将与恢复/管理残留的松树稀树草原直接相关，这些稀树稀树草原历史上覆盖了墨西哥湾沿岸平原的大部分地区，直到人为干扰将其减少到原来的2%。我们的研究地点是路易斯安那州东部的Whispering Pines女孩童子军营地，正在进行修复，以保护原始松树稀树草原的生物多样性，同时也有助于教育年轻人关于环境和科学的实地研究。因此，我们的研究将涉及大学生和年轻人，包括每年来访的6000多名女孩和领导。这些更广泛的影响将影响许多人，否则他们可能永远不会接触到大自然和保护自然资源的需要。

Pine savannas of the southeastern United States are among the world's highest diversity plant communities. They have non-continuous canopies often containing a single tree species (longleaf pine), and ground layers of vegetation containing many species of grasses, herbs, and shrubs. At small spatial scales of 1 - 1000 square meters, pine savannas commonly contain 50-200+ flowering plant species. In addition, more than 25% of the flora occurs nowhere else on Earth. Conservation of pine savannas as centers of high diversity necessitates an understanding of governing ecological mechanisms. A conceptual model was developed to explain high diversity in such plant communities. To test key predictions from the model, a large experiment that involves manipulations of fires, post-fire nutrients, seed dispersal, and competitive interactions among plants will run for three years and over two different fire cycles. Experimental results will be directly relevant to restoration/management of remnant pine savannas that historically covered most of the Gulf Coastal Plain until anthropogenic disturbance reduced them to 2% of their original extent. Our study site is the Camp Whispering Pines Girl Scout Camp in eastern Louisiana, which is being restored to conserve the biodiversity of the original pine savanna, while also serving to educate young people about the environment and field studies of science. Therefore, our study will involve university students and young people, including 6000+ girls and leaders who visit each year. These broader impacts will affect many people that otherwise might never be exposed to nature and the need to conserve natural resources.