Optimization of ecosystems services for sustainable coffee production under changing climate

Abstract

Legume cover crops have previously been evaluated for green manure, weed control and soil moisture conservation, this study includes further evaluation of biomass of the legume fodder. Our research was to compare soil nutrients and moisture concentration at different times in the treatment plots in the coffee plantation after the establishment of a desmodium legume cover crop with quantification of the resulting biomass as fodder for livestock. This case study conducted at the University of Nairobi coffee plantation evaluating different weed control methods in coffee using hand weeding, glyphosate (1.0 kg ha-¹ of acid equivalent) based herbicide and desmodium spp legume cover crop compared weeding costs and implications to farmers’ incomes in coffee production. Using completely Randomized Block Design 3 treatments replicated 3 times were analyzed for the annual weeding labour costs, soil nutrients, soil moisture and biomass production. Statistical analysis of soil moisture content and nutrients was evaluated among the treatments. Results indicated that coffee intercropped with desmodium had higher moisture retention of 36 % on average being higher than other treatment and desmodium legume fresh biomass production was extrapolated to 17,000 kgs per hectare per year. Desmodium spp planted was able to establish providing groundcover (90%) 18 weeks after planting inhibiting weed growth thus reducing the need for weeding as well as conserve soil moisture. There were significant savings on the cost of manual weeding with additional earnings or savings of 750 $ US from sales or utilization of the desmodium fodder per hectare. The study concludes that cover crops can enhance farmers’ resilience to changing climate utilizing the same size of land while enhancing output and increasing revenue. Policymakers need to realign extension services to introduce legume cover crops in coffee production to reduce the labour costs and the high doses of synthetic fertilizers which emit