Developing An Integrated Soil Fertility Management Decision Support Tool For Arabica Coffee (Coffea Arabica) In Selected Areas Of Northern Tanzania

EXTENDED ABSTRACT 

Coffee is one of the major export crops in Tanzania, contributing 24% to the agricultural gross domestic product (AGDP). The crop contributes directly to the livelihoods of over 420 000 farm families and indirectly to over 2 million people employed in the coffee value-chain. The Tanzanian average coffee production is variably pegged at 45 000 – 52 000 metric tons annually, while smallholder coffee productivity per tree ranges between 250 and 300g of parchment which is low compared to the world average of 500 – 600 g per tree. In the northern zone, for instance, annual coffee production trend indicates a decline over years as from 1980. During the first coffee stakeholders’ conference in 2009, soil fertility decline was pointed out by representatives of coffee growers as one of the most limiting factors for coffee productivity and sustainability. In the absence of a clear soil fertility intervention strategy in the coffee growing areas, with scanty and incoherent soil fertility data and limitations in their reliability and usability, it would seem impossible to verify the farmers’ claims or devise an intervention pathway. This formed the rationale of this work, whose objective was to develop a system that will make the soil analytical data useful for coffee farming. A model was required to quantitatively translate the soil data into estimated coffee yield, and also to recommend nutrient input application for best returns. This study was undertaken in Hai and Lushoto Districts, Northern Tanzania. The two districts were picked on merit of both growing coffee (thus experiencing the problem of coffee productivity decline) and each belonging to different geological origins (volcanic and metamorphic-gneissic parent materials, respectively). The first task was to establish the farmers’ perception of soil fertility decline as a problem and their attitudes towards integrated soil fertility management (ISFM) for coffee, thereby identifying the appropriate intervention strategies. Based on questionnaire data involving 126 respondents, both farmers’ awareness of the problem iii and their attitude were highly significant (at p