Estimating the joint effect of multiple soil conservation practices: A case study of smallholder farmers in the Lake Naivasha basin, Kenya

The current study seeks to assess the private benefits associated with multiple soil conservation practices (MSCPs) by estimating the marginal value of crop production that can be attributed to such practices. In areas where land degradation associated with soil erosion causes serious agri-environmental challenges such as loss of soil fertility, siltation and eutrophication, a multiple approach to soil conservation is neccessary. However, notwithstanding efforts to encourage adoption of such practices, their uptake remains generally low. Analysing the effect of MSCPs on crop productivity is one of the ways through which the incentives for soil conservation can be explored. To achieve the stated objective, the current study applied propensity score matching and exogenous switching regression techniques to cross-sectional data collected from a random sample of farm households located in Lake Naivasha basin, Kenya. Results indicate that there is a significant positive effect of implementing multiple soil conservation practices on crop productivity. However, we note that whether the additional benefits will cover the opportunity costs associated with the implementation of these practices will depend on farm specific attributes such as slope and the soil conservation effort. In cases where marginal benefits are not substantial to cover opportunity costs for implementation of soil conservation practices, intrinsic or external incentives could be necessary. Policy interventions could focus on offering technical assistance to farmers in selecting soil conservation practices that are best suited to their local condition.