Grasslands and savannas occupy almost 40% of the earth's land surface, are economically important as grazing lands, and are highly impacted by human activities. They also have tremendous conservation value, housing the world's remaining large grazing animals, particularly in Africa. A fundamental understanding of the factors most important for sustaining savanna grasslands, fire and grazing, is required for their management and conservation. Yet scientists have questioned whether grasslands in different regions function similarly. Convergence in function would mean that ecological understanding and conservation strategies could be generalized worldwide. But contingent factors specific to a region, such as differences in history or the types of grazers present may lead to unique responses in some savanna grasslands. The goal of this research is to compare key ecological processes to fire and grazing in savanna grasslands in North America and South Africa. Scientists will take advantage of three ongoing long-term experiments that manipulate these key factors and compare responses in productivity, biodiversity, and nutrient cycling.
As humans alter fire and grazing regimes worldwide, comparative research elucidating the consequences is needed to develop management strategies that can insure the sustainability of savanna grasslands. This research will provide the basic knowledge necessary to do so, and will afford training and important global and cultural experiences for young scientists, graduate students, and undergraduate students.