This project will map root and soil carbon in three dimensions at sites across a regional climate gradient in the Kalahari Desert of Botswana. The Kalahari is one of the only places on Earth where this type of natural experiment can be conducted without having to worry about problems of variations in soil characteristics. This research seeks to understand 1) how the distribution of roots in the soil varies among different plant species and across large distances, and 2) how carbon found in soils changes in response to climate change at multiple timescales.
Arid and semiarid regions, such as the Kalahari, cover over 40% of the Earth's land surface. Roots are an important component of the productivity and composition of these ecosystems, and play an important role in their response to climate variability. Thus, understanding the root structure of water-limited vegetation is vital to the study of the global biosphere?which includes its human inhabitant?and global carbon budgets amidst a changing climate. This research will address how belowground plant processes in water-limited ecosystems control belowground carbon dynamics under different climate conditions. The interdisciplinary nature of this research will include mentoring of graduate and undergraduate students from Botswana and the U.S., and collaborations with colleagues in Botswana. A short course on the research and related fields will be offered to high-school science teachers to encourage the discussion of plant-water interactions and active research in high school classrooms.
