DISSERTATION RESEARCH: Ecosystem Drivers of Disease Emergence: Linking Aquatic Eutrophication and Amphibian malformations

论文研究：疾病出现的生态系统驱动因素：水生富营养化与两栖动物畸形的联系

• 批准号: 0411760
• 负责人: Stephen Carpenter
• 金额: $ 1.2万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0411760&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Ecosystem; Drivers; Disease

Parasites and pathogens are among the most common members of most ecosystems and influence community structure, food webs, and even evolution. In recent decades, however, numerous diseases have emerged or re-emerged, frequently owing to changes in the environment of hosts and their parasites. In this study, I explore the direct and indirect causes of one such disease - widespread observations of severe limb deformities in North American amphibian populations. Many of these malformations are caused by a parasite (Ribeiroia ondatrae) that burrows into the developing limbs of larval amphibians. However, reasons for the apparent increase in infection remain unclear. I test the hypothesis that nutrient runoff into aquatic systems associated with agriculture and cattle production is responsible for promoting parasite infection. Ribeiroia has a complex life cycle involving passage among snails, amphibians, and birds. Excess nutrients (eutrophication) are expected to increase the numbers of snails that support the parasite, leading to more parasites in amphibians and therefore more deformities. By studying these relationships in the field, conducting ecological experiments, and using mathematical models, I investigate how increased nutrient inputs - a global problem in lakes, ponds, and rivers - affect the parasite, its hosts, and the level of deformities. Taken together, these approaches may offer new insights into the drivers of amphibian malformations while helping to advance an ecosystem-level approach to the study of disease.

寄生虫和病原体是大多数生态系统中最常见的成员之一，影响社区结构，食物网甚至进化。 然而，在近几十年中，由于宿主及其寄生虫的环境变化，许多疾病经常出现或重新出现。 在这项研究中，我探讨了一种此类疾病的直接和间接原因 - 广泛观察到北美两栖动物种群中严重的肢体畸形。 这些畸形中的许多是由寄生虫（Ribeiroia onDatrae）引起的，该寄生虫钻入了幼体两栖动物的发展四肢。 但是，感染明显增加的原因尚不清楚。 我检验了以下假设：与农业和牛的产量相关的水生系统径流是促进寄生虫感染的原因。 Ribeiroia的生命周期复杂，涉及蜗牛，两栖动物和鸟类之间的通过。 预计多余的营养（富营养化）将增加支撑寄生虫的蜗牛数量，从而导致两栖动物的寄生虫更多，因此会导致更多的畸形。 通过研究该领域的这些关系，进行生态实验并使用数学模型，我研究了养分输入增加（湖泊，池塘和河流中的全球问题）如何影响寄生虫，其宿主和畸形水平。 综上所述，这些方法可能会为两栖动物畸形的驱动因素提供新的见解，同时帮助推进生态系统级别的疾病研究方法。