The causes and consequences of diversity in ecological communities

我的长期目标是确定栖息地丧失和退化如何影响生态群落，以及生态群落的这些变化如何影响生态系统的结构和功能。 我将使用大规模的实验和研究合成技术来做到这一点。 在短期内，我将回答三个问题，1。生物间的相互作用在推动种群和群落动态方面重要吗？2. 全球两栖动物减少的主要原因是什么？3. 道路和道路建设如何影响池塘繁殖的两栖动物群落？为了回答第一个问题，我将使用两种方法。 第一个涉及整个池塘实验，其中6个池塘被一个从池塘表面延伸到池塘底部的大的不渗透帘分开。所有两栖动物物种被排除在6个重复池塘的一半之外，但允许进入另一半。 然后，我们监测水质和丰富的水生无脊椎动物和植物在两个半池塘，看看两栖动物群落在池塘动态中发挥重要作用。 第二种方法使用公开的数据集来检查生态群落中物种之间的协方差。 使用一个简单的统计程序，我们测试自然群落中物种之间的负协方差，为了回答第二个问题，我们将使用1000多个两栖动物种群时间序列的数据集，并研究两栖动物丰度与两栖动物衰退的可疑机制（如UV）之间的相关性。B射线暴露和栖息地的丧失和退化。为了回答第三个问题，我们设计了一个前后控制影响（BACI）实验，监测两栖动物种群在池塘附近的拟议道路建设领域，道路建设之前和之后。 我们将比较这些池塘随时间的变化与不在道路施工现场附近的类似池塘的变化。

My long-term objectives are to determine how habitat loss and degradation affect ecological communities, and how those changes in ecological communities affect ecosystem structure and  function.  I will do this using large-scale experiments and research synthesis techniques.  In the short-term I will address three questions, 1. Are biotic interactions important in driving population and community dynamics?; 2.  What are the primary causes of global amphibian declines?; 3.  How do roads and road construction affect pond-breeding amphibian communities?To answer the first question I will use two approaches.  The first involves whole-pond experiments where 6 ponds are split by a large impermeable curtain extending from the surface of the pond to the pond bottom. All amphibian species are excluded from one half of 6 replicate ponds, but allowed access in the other half.  Then we monitor water quality and the abundance of aquatic invertebrates and plants in both halves of the ponds to see if the amphibian communities play an important role in pond dynamics.  The second approach uses publicly available datasets to examine covariance among species in ecological communities.  Using a simple statistical procedure we test for negative covariance among species in natural communities, which we would expect if competition is an important driver of population and community dynamics.To answer the second question we will use a dataset of more than 1000 amphibian population time series and examine the correlation between amphibian abundance and suspected mechanisms of amphibian decline like UV-B ray exposure and habitat loss and degradation.To answer the third question we have designed a Before-After-Control-Impact (BACI) experiment to monitor amphibian populations at ponds near proposed road construction areas, both before and after road construction.  We will compare changes over time in those ponds with changes in similar ponds that are not near road construction sites.