Dr Edmund Tanner
Find out more about Ed Tanner and his Group or email Ed.Tanner@plantsci.cam.ac.uk
Project titles:
Project Title: Root and mycorrhizal responses to changing nutrient availability in a tropical forest.
Supervisor: Dr Ed Tanner
Project outline:
We know that roots and mycorrhizas respond to differences in nutrient availability, usually plants increase their root fraction in soils with low nutrient availability; however much of this work is based on crop plants and is done in pots. Working in tropical forest we have reduced nutrient availability by continuously removing litterfall for five years and our measurements of root biomass show that roots are reduced in the litter removal plots not increased, i.e. just the opposite of the paradigm (Sayer et al. 2006 Plant & Soil 281, 5-13). We also have plots where nutrients are increased by adding litter and these also show reduced root biomass. We now need to investigate these finding by measuring fine root and mycorrhiza production and turnover to establish whether production is reduced as well as standing biomass. Thus this project would quantify root and mycorrhizal production in forest plots using root scanning techniques and ingrowth cores combined with plastic meshes of two hole sizes (one to exclude roots the other to exclude mycorrhizas). We would then be able to answer the general question of how root and mycorrhiza production in tropical forest respond to changes in nutrients. Changes in nutrients are likely to become important in tropical areas as tropical developing countries increase their populations and increase the intensity of their agriculture, both of which will increase ‘accidental’ nutrient supplies to tropical forests. The project would be based at the Smithsonian Tropical Research Institute in Panama, a large and well-established tropical research station.
See Research or email: Ed.Tanner@plantsci.cam.ac.uk