An integrated spatial econometric approach in valuing soil conservation using contingent valuation

Abstract

The integration of soil value in agronomic micro-level decision-making and macro-scale policy development has grown immensely in recent years. Major threats to soil resources and their impact on human well-being require a comprehensive estimation of soil's economic worth, highlighting the need for sustainable and pragmatic conservation strategies. However, the absence of formal markets for numerous soil amenities, coupled with the heterogeneity of stakeholder cognition and spatio-environmental factors, obfuscates the valuation process for soil and similar public goods. This paper aims to address such concerns by evaluating stakeholders’ willingness to pay (WTP) for soil conservation as a proxy indicator for its explicit value. Two contingent valuation method (CVM) formats, the payment card (PC) and the dichotomous choice (DC), were used to analyse WTP in Norzagaray, Philippines. Results suggest farmers’ income, education, land tenure type, level of environmental consciousness and proximity to amenities influence their inclination to spend on soil conservation measures. Econometric analyses indicate a compensating surplus corresponding to the mean WTP estimate of ₱79.98 (PC-CVM) and a Turnbull WTP estimate of ₱99.47 (DC-CVM). Estimated WTP values can be used in future benefit-transfer studies, and the findings of the econometric models can be used in developing strategies that would promote greater stakeholder acceptance and participation. The approach presented here provides another step towards a more comprehensive characterization of soil value that integrates environmental valuation and econometric modelling with geospatial data.