Assess organic oil palm production systems in Sierra Leone


In sierra Leone oil palm cultivation is just starting and one of the major investments is a Dutch company aiming for organic palm oil production. Their next step is to start oil palm production with smallholders. The NGO Solidaridad is facilitating contacts with smallholders. Currently oil palm is cultivated as monoculture. During its cultivation the plantation needs to be weeded, trees need to be pruned, and fresh fruit bunches are exported from the plantation to a mill for oil extraction. Furthermore the crops receive fertilizer or manure to support their fruit production. There are hence different sources of biomass identified related to oil palm production and each of these contain nutrients and carbon. Aiming at sustainable palm oil the optimum use of the nutrients and carbon are key. Biomass such as prunings are currently used as mulch in the plantation but could also serve as animal feed or be exported from the plantation to serve as resource for the biobased economy. Equally the destiny of the waste of the mill is important as it could be returned to the plantation or for instance used as source of energy.

The research proposed is first a literature research about different biomass sources and their nutrient and carbon content. Secondly, to identify the alternative uses of these sources. Thirdly, which biomass sources, in which amount or form are needed to maintain or enhance the productivity of the oil palm plantation. Or in other words which and how much biomass can be used in biobased economy without negative feedback on the plantation. 

We already have a preliminary nutrient cycling model that needs upgrading. We have research outputs by two PhD students that did measurements on carbon flows in oil palm plantation in relation to management and soil type. 

-       Our second aim is to make a nutrient cycling model, including all nutrient sources, in relation to management of plantation and the mill. 

-       Our next aim is to make a carbon cycling model, including all carbon sources in relation to management of plantation and the mill.

-       Our final aim is to being able to assess what can best be done with biomass of palm oil production (and processing) based on palm nutrient needs, GHG emissions and economics. 


We work together with Natural Habitats.  


General PPS thesis prerequisites apply. Good background on nutrient and carbon cycling needed. Affinity with modelling is a benefit for this topic.


As soon as possible


Wageningen (for literature research) and perhaps Sierra Leone fieldwork. 


Maja Slingerland                                0317 483512                 

Wolter Elbersen (AFSG - Biobased Research)                        

Lotte Wottiez