OZR backup mandate: The interplay of plants, mammalian herbivores, insects and global change in savanna

Mammalian herbivores, through their dung can change the balance or stoichiometry of growth-limiting nutrients, like nitrogen (N) and phosphorus (P), thus impacting plant community composition. It is increasingly recognized that the N:P stoichiometry of dung varies considerably among herbivore species, in turn influencing soil N and P availabilities and likely plant competitive interactions. But the influences of herbivore dung on plant communities is difficult to detect in nature as herbivores simultaneously consume plants. Also, the roles that dung-decomposing insects, as dung beetles and termites, play in this chain of processes is unclear. This project will examine how herbivore consumption and dung deposition impact plant competitive interactions. It aims also with quantifying consumption and dung deposition in a tropical savanna in Kenya, to evaluate its overall importance on a landscape scale. It will use the
theory of ecological stoichiometry as a novel approach to understand this impact, in combination with the effects that global change, through increased CO2 and/or N might have on these processes.
The research will combine field surveys with much-needed experimental work in providing important new patterns and insights on the functioning of savanna ecosystems and the role herbivores play in it – now and in the future. This type of information will be valuable for savanna conservation and management.