CAREER: Investigating Biodiversity Cascades in an East African Savanna

9874776基辛热带稀树草原覆盖了非洲50%的面积，孕育了惊人的生物多样性。这些稀树大草原主要是高密度和高多样性的大型哺乳动物，特别是有蹄类动物和食肉动物。因此，热带稀树草原群落生态学研究的重点一直集中在这些显眼的哺乳动物身上。这种强调掩盖了人们对这些优势生物的影响如何在其群落中产生反响的兴趣。这个CAREER研究项目将研究有蹄类生物多样性是如何在稀树草原群落中产生级联效应，通过干扰和草食影响小型哺乳动物、植被和节肢动物的多样性和丰度的。该项目将探讨热带草原生态系统内生物多样性变化的原因和后果，这是一个具有重要理论和实证意义的课题。该项目将利用肯尼亚中部Mpala研究中心现有的野外圈地实验。研究的具体目标是：(1)在排除大型哺乳动物的情况下，小型哺乳动物是否可以补偿大型哺乳动物的食草性；(2)大型有蹄类动物是否通过干扰增加了小型哺乳动物的多样性及其对植物和节肢动物的影响；(3)小型哺乳动物的局部密度是否影响木本植被的补充。研究将由PI和锡耶纳学院的一些本科生进行。参与该项目的学生还将与奥尔巴尼纽约州立大学评价协会合作，参与教育研究。教育研究将决定学生对科学知识本质的信念在多大程度上影响他们对研究的参与，以及受其影响的程度。因此，该项目将把PI和学生调查员关于非洲大草原生物多样性的原因和后果的科学研究与关于学生如何学习科学过程的教育研究结合起来。

9874776KeesingSavannas cover 50% of the area of Africa and harbor a spectacular diversity of organisms. These savannas are dominated by the presence of both high density and high diversity of large mammals, particularly ungulates and carnivores. Consequently, the focus of most research on savanna community ecology has been centered on these conspicuous mammals. This emphasis has obscured interest in how the effects of these dominant organisms reverberate through their communities. This CAREER research project will investigate how the effects of ungulate biodiversity cascade through a savanna community, affecting the diversity and abundance of small mammals, vegetation and arthropods through disturbance and herbivory. This project will address both the cause and the consequences of changes in biodiversity within savanna ecosystems, a topic of great theoretical and empirical importance. This project will take advantage of an existing field enclosure experiment at the Mpala Research Centre in central Kenya. Specific goals of the research are to investigate (1) whether small mammals can compensate for herbivory by large mammals when the latter are excluded, (2) whether large ungulates increase small mammal diversity through disturbance and its effects on plants and arthropods, and (3) whether the local density of small mammals influences recruitment of woody vegetation. Research will be conducted by the PI and a number of undergraduate students from Siena College. Students participating in the project will also be involved in educational research, in cooperation with the Evaluation Consortium of the State University of New York in Albany. Educational research will determine the degree to which students' beliefs about the nature of scientific knowledge influence and are influenced by their participation in research. Thus, this project will integrate scientific research by the PI and student investigators on the causes and consequences of biodiversity in African savannas with educational research on how students learn about the process of science.