ABSTRACT

Soil erosion by water is the principal cause of land degradation, and a major constraint to agricultural development in many countries. Soil and water conservation (SWC) measures have to be taken not only to reduce on-site soil, water, and nutrient losses, but also to diminish negative downstream effects, such as flooding and the silting up of reservoirs. It is however extremely difficult to appraise such SWC measures economically, since neither their effects nor their beneficiaries can be easily detected. For the appraisal of SWC projects much attention therefore needs to be paid to the identification of all actor groups involved and to an assessment of all major on-site and downstream effects of the measures. This requires both socioeconomic research and hydrological and erosion research, and a thorough integration of biophysical and economic aspects. In the impact assessment, use can be made of water and nutrient balances and yield response functions, which can be incorporated in spreadsheet models. In the subsequent economic appraisal use can then be made of both cost–benefit analysis (CBA) and multi-criteria analysis (MCA). The efficiency of the projects can be conveniently assessed with CBA, when the effects can be quantified and valued. Whereas MCA can be used to assess scores on non-monetary attributes of the various evaluation criteria, and can also show how conflicting objectives of different actors affect these scores. This paper provides a brief framework and practical examples for such an economic appraisal of SWC projects.