COST-BENEFIT ANALYSES FOR MORE SOIL CONSERVATION

Soil protection pays off

Every year, the area of leached, infertile soils increases. It is estimated that 24% of the world's usable soils have already been degraded. Deforestation, overgrazing, salinization, overfertilisation, pollution and the depletion of nutrients have contributed to this. Cultivation methods that drive wind and water erosion and other risks are responsible for this, despite the fact that land management methods that conserve the soil are already well known and practice-approved. Among these methods are reduced tillage, erosion control, organic farming and agroforestry measures. However, the failure to extend the use of these methods often results from unfavourable economic conditions, which are not given due consideration by policymakers. Therefore, the degradation process of land continues – with devastating consequences, in particular for the poorer parts of the population who are directly dependent on intact land resources for their livelihoods.

As fertile soil becomes scarce, conflicts arise and forests are increasingly overexploited. With rising food prices people are starving and are no longer able to make their living in rural areas. Damage to soil can be ascertained from its ability to benefit the ecosystem. Degraded soils absorb less water and - lose their purification properties. They store less carbon and thus contribute to climate change. This also has significant economic consequences. According to estimates, soil erosion alone costs each person in the world 60 Euros a year.

The global initiative ‘Economics of Land Degradation’ (ELD), with its Secretariat hosted by GIZ, is introducing an economic perspective to the problem and is bringing this into political debates. ELD demonstrates that soil conservation pays for itself. Decision makers at local, national and international levels are provided with arguments why soil conservation makes sense, also from an economic perspective. In this regard, the ELD initiative has already conducted numerous studies around the world. On the one hand, the costs of soil degradation have been calculated based on the loss of ecosystem services. On the other hand, benefits from investment in sustainable land management are calculated and compared with the costs. The methodological approach was developed with the help of internationally renowned scientists, and the studies were conducted by prominent economists and ecologists. The cost-benefit calculations have been positive in every case so far, even though it takes a few years before there is a return on investment. It is worth investing in the conservation and sustainable use of soils.

An example for these economic benefits are terrace cultivation and agroforestry measures in Kenya. To shift to this kind of sustainable use, the farmers first require government subsidies, but the new practices provide long-term benefits for their businesses and the economy. Further investigations illustrate, that for example reforestation and agroforestry measures in Mali or investment in mixed crops in Sudan are worthwhile and make - sense economically. In the Ethiopian highlands, the Initiative calculated, based on various scenarios, , that if land management practices continue unchanged for the next 30 years, agricultural yields will decrease by 5%. By contrast, an increase in returns in excess of 10% can be expected by adopting more sustainable land management methods. All of these examples provide politicians and financial institutions with a better basis for investment decisions with far-reaching benefits.

Video of the project „The Value of Soil”

Due to the success of the initiative, it has recently received additional funding from the EU and the Federal Ministry for Economic Cooperation and Development (BMZ). Local qualified professionals in eight African countries are learning how to independently carry out economic analyses based on the ELD methodology. Further studies are being conducted jointly in selected problem regions. The results will strengthen the political dialogue and investments in sustainable soil management.