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Inappropriate management of agricultural irrigated land, using excessive amounts of production factors – pesticides and fertilizers in particular – can lead to rapid and irreversible soil degradation and the corresponding decrease in production capacity. The method presented here, applicable to the entire Mediterranean region, was designed to support the sustainable management of a 12540 ha irrigated area located in the Spanish- Portuguese border, with special emphasis on the prevention of desertification. This specific tool, incorporates a data collection from 1428 georeferenced points and respective topsoil samples, describing soil type, depth, slope, drainage, pH, organic matter content, electrical conductivity, exchangeable sodium content, and available phosphorus and potassium. Parameterized maps were prepared for all these soil properties using Geographic Information System (GIS) software to store, manage, analyze, and display the georeferenced information. Predictive maps for organic amendments need were elaborated for use in the sustainable and integrated land management of the area. The higher risk zones were identified on the basis of their soil depth, slope, drainage, organic matter, electrical conductivity, and sodium saturation percentage.

Wildland fire is a major disturbance promoting landscape changes and triggering desertification processes in the Northern Mediterranean basin. Addressing that issue in the long term requires both fire prevention and pot-fire restoration measures. Post-fire restoration should mitigate ecosystem degradation, and improve ecosystem regeneration rate and quality.

Fire is one of the most important determining factors in the evolution of Mediterranean ecosystems. Its effects on soil are plural and diverse, acting on structure, chemical and physical properties, biota etc. Among them, the induced variations on soil water dynamics are of key importance for the recovery of the entire ecosystem and in the soil response to erosion processes. Forest fires are also a factor, triggering the risk of desertification. The aim of this study is to assess the impact effect of different fire intensities on soil hydrology and on runoff generation.

In Mediterranean regions, water erosion is strongly linked to desertification and relates mainly to constraints of land use. Soil and water play very important roles as production factors in agriculture and forest crops, so they are of almost importance in the management of forest soils for sustainable productivity.

Desertification is the consequence of a series of important processes in the Mediterranean environments, especially in semi-arid and arid regions, where water is the main limiting factor of land use performance on ecosystems. Among the most important processes of desertification are soil erosion and salinization particularly affecting hilly areas and lowlands, respectively. Various methodologies have been developed in identifying and mapping environmentally sensitive areas (ESAs) to desertification. Studies have shown that the various types of ESAs have different behavior on crop production, plant growth, grazing capacity, and soil erosion rates. For example, olive oil and cereal production decreased as the type of ESA changes from non-threatened to critical areas. Soil erosion measures have shown that soil erosion rates increased as the sensitivity of land to desertification increased. Loss in land productivity greatly affects farmer's income and measures applied for protecting the land from further degradation and desertification.

Groundwater resources in Morocco are expected to shrink in the next decades due to an increasing withdrawal for rural and urban development, and a decreasing internal recharge by precipitation under the influence of climate change. The objective of this work is to analyse the recharge of groundwater systems in a region with traditional agriculture and current transformations in northern Morocco (Sehoul region) in response to future climate change and land degradation. Models were used to simulate climate change and effects on surface runoff and groundwater recharge. The climate models indicated increases in temperature and decreases in precipitation in all seasons in 2050 compared to 1990, and an increasing variability of autumn precipitation. Because most cultivated fields are freshly ploughed and sown in autumn, this will increase the risk of desertification due to declining groundwater recharge and increased surface runoff and erosion. This is confirmed by the results of the event-based surface runoff simulation for the 2050 climate. Surface runoff is mainly produced in ancient grazing fields and fallow fields. In view of the current transformation of collective grazing fields into cultivated land, problems with loss of rainfall in surface runoff and soil erosion could be mitigated by 1. early tillage of cultivated fields along the slope contour, followed by leveling, 2. locating cultivated fields downslope of grazing fields to enable the capturing of diffuse surface runoff coming from the grazing fields, and 3. leaving fallow fields untilled and covered with crop remnants.

Land degradation, which affects the conservation of soil and water in adequate places, amounts and qualities, is the main direct cause ofdesertification. It is related to climate and soil characteristics, but mainly todeforestation and inappropriate use and management of natural resourcesincluding soil and water. The main effects are a decrease in water supply, anon sustainable agricultural and food production, and increased risks ofcatastrophic flooding, sedimentation, landslides, etc. In the medium or longterm, the previewed global climatic changes may contribute to acceleratethe processes of desertification in the Mediterranean Region, but in the shortterm, land use practices leading to soil degradation processes wouldincrease the negative influence of those changes.

As stated by the United Nations Convention to Combat Desertification (UNCCD), desertification or land degradation is at the root of political and socio-economic problems and poses a threat to the environmental equilibrium in affected regions. That desertification and political instability are interlinked should not be a surprise, the UN states that half of the 50 armed conflicts in 1994 had environmental causal factors characteristic of drylands (i.e., land degradation). One example cited states that the land’s loss of productivity exacerbates poverty in the drylands, forcing its farmers to seek a way of living in more fertile land or cities. In fact, over one billion people are affected as a direct consequence of desertification including 135 million people who are at risk of being displaced.