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The assessment of soil erosion rate, especially in agricultural lands, represents a fundamental tool for land management planning in the long-term period. In this study, the SWAT model was utilized to simulate soil erosion within a semi-arid watershed in South Portugal. The model was successfully calibrated and validated using real data of streamflow and river sediment transport in four hydrometric stations. Soil erosion susceptibility maps (historical and future) were realized to highlight the evolution of the phenomenon through time. The historical period was confirmed to be the worst one in terms of average soil erosion for each land use, followed by the Representative Concentration Pathways (RCPs) 8.5 and 4.5 scenarios. The main differences in soil loss among the two RCPs will be influenced by the slightly increasing trend of extreme events which will characterize the RCP 8.5, leading to a higher maximum value of soil erosion. Results highlighted the tendency to erosion of Leptosols and of the agro-forestry system (“montado”), which influenced the soil erosion susceptibility distribution of the whole basin. The study confirmed that Leptosols are the most subject to sediment loss due to their intrinsic characteristics, and that “montado” and farmed systems will negatively influence soil erosion rate if anti-erosion actions will not be adopted, stressing the need to identify all aspects responsible for land degradation in Mediterranean watersheds.

Increasing scientific evidences indicate that agroforestry is a land use that can support economic, social and environmental sustainability, thus promoting resistance and resilience towards ongoing climate changes. The implementation and management of agroforestry systems still face social, economic and political barriers. Mediterranean agroecosystems suffer from increasingly negative climate change effects and urgent measures are needed to improve their rural economy while protecting soils and the environment. In this context, the LIFE Project Desert-Adapt: “Preparing desertification areas for increased climate change” (http://www.desert-adapt.it), aims to demonstrate the feasibility of innovative climate adaptation strategies and measures, based on the agroforestry concept, over 1000 hectares at risk of desertification in Italy, Spain and Portugal. The core of the project is the Desert Adaptation Model (DAM), an integrative development model fitted to the specific requirements of each farm which guide the implementation of sustainable agroforestry systems (e.g. montado, dehesa). The results will be evaluated through an array of multidisciplinary social, economic and environmental indicators. The project will deal with the most common conceptual, technical, and legal constraints encountered along the implementation and management of agroforestry systems in marginal lands and its results will fill the gap between farmers’ needs and policy makers at local and global level.

Geothermal energy is one of the most environmental-friendly and cost-effective energy sources with potential to replace fossil fuels and help mitigate global warming. Recent technological progress, energy price variability, difficulty of oil and gas supply from foreign countries and the need to reduce fossil fuel deployment have made the exploitation of geothermal energy, especially for heating and cooling purposes, an attractive and viable energy alternative. The choice of the proper geothermal system (for heating or cooling) is essentially based on the need of cost containment and environmental constraints. These two requirements have led through the years to an enormous research in the sector of geo-exchangers and many improvements have been achieved so far. Today, the choice of design and installation is no more restricted to the traditional open loop versus closed loop. This chapter reviews the main innovative geo-exchanger systems currently available on the market (2014) and highlights their applicability and efficiency as well as advantages and limits.