
GEST
Global Experiment on
Savanna Tree Seedlings
GEST is a comparative experiment
of seedling growth of savanna tree species, based on increasing evidence that
the seedling stage of tree growth is critically important to the long-term
dynamics of savanna systems. Research worldwide suggests there are differences in the
environmental limitations constraining savanna tree seedlings in wet
environments (nutrients, light, fire) and dry environments (water, nutrients,
grazing). In addition, biogeographical studies have indicated that regional
distribution of tree species in tropical and sub-tropical savannas in Africa,
Asia, Australia and the Americas, is related to rainfall gradients and to soil
fertility, suggesting that different tree growth traits are required
for each of these environments.
Questions
1. Do tree seedlings respond differently to resources in savannas around the
world?
2. Do tree seedlings differ in their ability to compete with grasses for
different resources? Under which conditions are competition for nutrients, light
and water important?
3. Do tree seedlings differ in their ability to tolerate defoliation?
4. Do the species’ seedlings show convergent traits for environmental conditions
(annual rainfall X soil fertility), or are the differences related to continent
of origin, or to phylogeny?
Methods
Funding
GEST is predominantly funded through a grant from Shell Research Foundation.
