Ecosystem Services and Land Degradation in Gishwati-Mukura Corridor, Rwanda: Cost-Benefit of Sustainable Land Management Practices

Gishwati and Mukura Forests are among the fragile ecosystems that face high rates of land degradation in terms of deforestation, loss ofnbsp; biodiversity, soil erosion and landslides because of intense agriculture and overgrazing, and mining activities. Sustainable landnbsp; management practices are therefore needed for restoring ecosystem services within Gishwati-Mukura Corridor. Four scenarios that havenbsp; been considered include (1) business as usual where costs and benefits of the current land use systems were analyzed; (2) landscapenbsp; restoration by terracing, agroforestry, use of fertilizers and improved seeds; (3) restoration by planting and retaining exotic speciesnbsp; (eucalyptus); and (4) restoration by planting and retaining indigenous species. Data were collected through the Focus Groupsnbsp; Discussions. Geographic Information Systems (GIS) analysis helped to calculate the land area for afforestation, grazing, and cropping.nbsp; Google Earth image was also used to digitize and estimate the number of households to be compensated. A cost-benefit analysis wasnbsp; performed to compare the implementation costs of sustainable land management against its benefits. Sensitivity analysis was alsonbsp; carried out to determine how target variables are affected based on changes in other variables to know the most sensitive parametersnbsp; and the land management option that provides the best Net Present Value (NPV). Results show that the restoration by exogenous speciesnbsp; offers the highest economic and environmental benefits with a NPV of 40,690,477.7 USD. This is followed by the sustainable landnbsp; management option with a NPV of 34,048,663.7 USD and the business-as-usual scenario with a NPV of 21,915,102.8 USD. The rehabilitation of the corridor by exogenous species is less profitable as it shows a NPV of - 9494381.7 USD. Under all scenarios, the NPV isnbsp; more influenced by changes in input and output than the discount rate. However, an increase in input prices leads to higher negative changes in NPV. Moreover, NPV is positively affected by an increase in output prices, implying high demands and high prices for foodnbsp; products (milk and Irish potatoes). Although maize cropping offers high economic returns to local communities, it requires however huge investments. Local communities can bear the costs of soil conservation and fertility improvement when there is a potential for annbsp; increased yield and good price of their agricultural products.nbsp;