INTRODUCTION

The Ecoregional project on system prototyping and impact assessment for sustainable alternatives in mixed farming systems in high-potential areas of Eastern Africa aims at characterizing mixed farming systems according to their management objectives. It further aims to combine prototyping and simulation modeling to map improvements of the farming systems and to model interactions between crops and livestock on different scales. It also wishes to assess natural resource management interventions that promote sustainability of prototype farming systems and to develop and disseminate the methodology that can be used in subsequent initiatives within the region. The project is funded by the Ecoregional fund, and is a joint collaboration between Wageningen University, ILRI, the Kenya Agricultural Research Institute (KARI), ICRAF and the International Consortium for Agricultural Systems Applications (ICASA). The project is being carried out in three districts in Kenya: Kiambu in central region, Kilifi in the coast and Vihiga in western.

Prototyping methodology is based on a sequential process that starts with the identification of farmers' general and specific objectives. Then, potential prototypes are identified from the clusters that delineate typical farming systems as well as interventions that can be used to attain desired objectives. Participatory modeling is used to test if the interventions as prescribed are acceptable, manageable, viable and effective in a sustainable manner.

This process was initiated in Vihiga where interventions were identified jointly with prototype farms and the project team. It is quite clear that there are wide gaps in what farmers know and they are very eager to learn about better management practices and alternative enterprises. The farmers have already taken up improved manure/compost management and recommended inorganic fertilizers as a way of improving soil fertility and ultimately food supply and farm incomes. A few farmers are also shifting towards cash crops such as tea and high value vegetables as a way of improving farm incomes.

Results from modeling of the 'deal farm' situation show low net income, utilization of family labor only, sale of cash crops and milk, purchase of food crops and Napier grass, and overall nitrogen losses. Net incomes improve when most plots are not allocated to food crops. The team is assessing potential impacts of interventions on intensification of crops and livestock as well as shifts from subsistent production to commercial production of both crops and livestock. The outcomes will be presented back to the farmers for discussions before the next planting season.