Kindu Mekonnen, SLP associate researcher of the East Africa team writes:
“Biomass is a crucial resource for smallholder farmers. Crop residues form an important source of biomass but there are competing demands for its use. The key trade-off is between use of crop residue for feeding of livestock and retaining residues on the field to sustain soil fertility. This issue has formed the basis of a global research project on trade-offs in residue use in smallholder systems. In East Africa, the research has focused on two sites in Ethiopia and one in Kenya.
As part of this research a village survey was conducted each site with the objective understanding diversified and competing uses of crop residues; analyze past trends of uses of crop residues; and identify production and utilization constraints of crop residues. A total of 8 villages per site were surveyed in two sites in Ethiopia (Kobo and Nekemte) and one site in western Kenya (Kakamega).
The most important findings from the research so far are (1) The use of crop residues for animal feed (stall feeding and direct grazing) surpassed the other competing uses in all the sites; (2) The practice of mulching crop fields using crop residues has declined in the last 10 years in the three sites because of competing use of the resources for various services and products; (3) Soil/land related problems, weed, insect and pests, high input/low output prices, poor distribution of rainfall/drought and lack of information/services are some of the constraints associated with low crop productivity and production of crop residues; and (4) Lack of modern crop residue processing technologies limited the efficient utilization of crop residues in the three sites.
The pressure on residue use and the decline in its use as a mulch raise serious concerns for system sustainability. Our next task will be to look at policy, institutional and technical options for reducing pressure on biomass in smallholder systems for the long term benefit of poor smallholders.
We will present this work at the International Congress: Water 2011– Integrated water resources management in tropical and subtropical dry-lands. The congress will be held from 19 to 26 September 2011 in Mekele, Ethiopia. The title of our presentation is “Competing uses, dynamics, and production and utilization constraints of crop residues in East Africa: Implications for conservation agriculture”.