The relationship between the ability of afforestation and deforestation to respectively increase or decrease the amount of precipitation and evapotranspiration and its effect on the water balance and ecosystem of a region is particularly important to the resilience of vulnerable groups to the challenges of climate change. In regions of the world with increasing forest tree cover loss coupled with water scarcity such as Tunisia, alternative water sources such as treated municipal wastewater reuse can play a crucial role in supporting afforestation/reforestation projects that can have positive effects on the regional water balance and ecosystem hence improving climate resilience. This StMUV funded project aims to characterize the scientific, geographicclimatic (climate change), technical as well as socio-economic basis in Tunisia to carry out a partnership-based reforestation to influence the water balance of the region in a sustainable way. The reforested area should be able to achieve the following long-term goals:

• Serve as a carbon sink to capture CO2 and regulate the local climate.
• Generate additional precipitation by reactivation of the biotic pump and thus provide enough water for the forest and the surrounding area.
• Contribute to the socio-economic development of the local population.
• Serve to a limited extent as a communal area for the local population for preservation and protection.
• Provide evidence of the positive influence of reforestation on soil characteristics (e.g. moisture content). This can provide valuable knowledge for the Bavarian Ministry for the replication of reforestation projects in Bavaria.

The preservation of the forest must be of clear economic benefit to the population for sustainable project implementation. The project therefore aims to facilitate acceptance for the long-term project sustainability through involvement of all stakeholders from the project outset. The lessons learned from this project will add to the existing knowledge on relationship between loss of forest tree cover (deforestation) and increasing water scarcity.