Conversion of forests to smallholder rubber and oil palm plantations: landscape-scale and inter-annual variations of soil greenhouse gas fluxes (GHG) and the contribution of tree-stem emission to soil GHG budget

Joost Koks focuses on the soil-atmosphere exchange of trace gases and the factors which are known to control these fluxes. He will measure the emission of soil greenhouse gasses (GHG) under different land use types (forest, jungle rubber, rubber, oil palm) in Jambi province, Sumatra, Indonesia.
His research aims at identifying the inter-annual variation in GHG emission, for instance, as a result of changing weather patterns. He will measure the emission by sampling air from installed plastic chambers. The result will be compared with previously gathered data.
Joost´s research also tries to identify the influence of topography on the soil GHG emission. These emissions will be measured on plots located on higher grounds (highlands) and on lower locations (depressions, so-called riparian sides) and then compared with each other.
Not solely soil, but also vegetation plays a role in the total GHG budget. The GHG emission of trees via their leaves is taken in account in other research projects, but so far only little is known about the GHG emission of tree stems. Joost will measure this emission by designing a plastic ´chamber´ around selected trees and measure the changing air concentrations after closure.
The results will be used to gain a better understanding of the processes involved, when considering GHG emission. In turn, this understanding helps decision makers with establishing desired management practices for the increasing oil palm and rubber industry.