Dissertation Research: The sensitivity of kettlehole ecosystems to abrupt drought-induced transformation

全球环流模式预测下个世纪的水文气候变率将增强，可能超过20世纪观测的范围。生态学家面临着预测生态系统对这些变化的潜在反应的关键挑战。本论文拟以威斯康星州北部壶孔盆地为模型系统，研究过去水文气候变化对生态系统结构和功能的影响。这项研究的目的是验证这样一种假设，即这些系统中泥炭地的建立和扩张是对气候变率的阈值反应，与表明气候敏感性有限的流行模式形成对比。方法将包括对来自多个壶穴生态系统的湖泊和泥炭地沉积物岩心进行详细的古生态分析。将古生态数据与盆地形态和景观位置信息相结合，建立不同全球气候变化情景下的壶洞生态系统动态模型。拟议的项目将增加我们对生态系统状态变化的潜在理解，以应对未来的气候变化。研究结果将有助于资源管理者预测未来一个世纪壶穴生态系统的潜在变化，以及这些独特系统提供的生态系统服务的变化。此外，作为本研究的一部分开发的预测模型将在开源软件中编码，并配备直观的图形用户界面，使资源管理人员，教育机构和学生能够访问。

Global circulation models predict enhanced hydroclimatic variability in the next century, likely exceeding the range of 20th century observations. Ecologists are faced with the critical challenge of anticipating potential ecosystem responses to these changes. This proposed dissertation research will use kettlehole basins in northern Wisconsin as model systems to study the effects of past hydroclimatic variability on ecosystem structure and function. The research is designed to test the hypothesis that peatland establishment and expansion in these systems is a threshold response to climate variability, in contrast to prevailing models that suggest limited climate sensitivity. Methods will include detailed paleoecological analyses of lake and peatland sediment cores from multiple kettlehole ecosystems. Paleoecological data will be integrated with information on basin morphology and landscape position to develop a model of kettlehole ecosystem dynamics under various global climate change scenarios. The proposed project will increase our understanding of the potential for ecosystem state-shifts in response to future climate changes. Results will help resource managers anticipate potential changes in kettlehole ecosystems in the coming century, as well as changes in the ecosystem services provided by these unique systems. In addition, the predictive model developed as part of this study will be coded in open-source software and equipped with an intuitive graphical user-interface, enabling access by resource managers, educations, and students.