Climate change is a critical factor affecting natural and human systems that are already in constant flux. Is it possible to separate out the impact of climate change from human impacts on the ecological system when they are interacting with each other? This question is being examined in the savannas of East Africa, where vegetation and society are expected to be particularly impacted by climate change. These areas are dominated by pastoralism and, in some areas, by wildlife. They are at the expanding edge of cropped agriculture. Climate change is leading to warmer temperatures, to altered precipitation patterns, and to significant losses of productivity in some places. These shifts and more frequent extreme rainfall events will profoundly affect the ecosystem and the livelihood systems dependent on livestock and natural resources. Human responses include altered livestock and cropping land-use systems, but at some point, natural resource-based livelihoods may simply not able to satisfy the needs of households, thereby leading to a tipping point of change. This interdisciplinary research project will conduct an analysis of the interactions among climate, human activity and land use through a case study of change in three different savannah-based regions in the east African nations of Kenya, Tanzania, and Ethiopia. The investigators will explore these relationships from a number of perspectives, including political ecology, landscape ecology, and resilience theory. Multiple methods and information sources will be used to identify processes and their impacts on the integrated system. At the regional level, the investigators will incorporate climate and vegetation modeling and analyses of satellite imagery in their work, while at the case-study level, they will include surveys, household decision modeling, plant species counts, and forage analysis.
This project will provide new information about the impact of climate change on savanna ecosystems and will contribute to answering questions on the relative importance of land use affecting climate. It will develop and test a comprehensive methodology that integrates state-of-the-art methods in the natural, social and statistical sciences. The approach and analyses will inform research in similar ecosystems around the globe. They will add to scientific knowledge on interactions and feedbacks among climate, land, and society and on complex system modeling. The results will contribute to society's awareness of the impact of climate change and will inform options for adaptation and mitigation. The research also will provide critical information for agricultural research and policy as well as both research and practice in conservation and economic planning. This project is supported by an award resulting from the NSF competition focusing on the Dynamics of Coupled Natural and Human Systems. NSF's Office of International Science and Engineering also is providing support for this project.
