Hydrological Approach for Evaluating Soil and Water Degradation Processes in a Changing Environment

Soil is fundamental to the needs of human life, and plays a central role in determining the quality of our environment. The importance to preserve soils in some crucial aspects for human life, like food production, earth hydrological cycle, biodiversity, and air composition, will be constantly increasing. The expansion and intensification of agricultural activities and increased number and size of populated areas, results in a changing environment, frequently associated with widespread soil and water degradation, due to inappropriate land use and management. Those degradation processes and the associated hydrological changes may result in increasing risks and problems of food and water supply for mankind, and in more frequent “natural” disasters like droughts, flooding, landslides, sedimentation, and contribute to the loss of biodiversity and global climatic changes. All these problems may be evaluated and previewed through modeling the hydrological and hydro-geochemical processes in order to achieve the required sustainability of the environment. This is possible through the integrated use and management of soil and water resources adapted to new social and economic pressures, and to the previewed climate changes. Some examples of such approach under different social-economical and biophysical conditions, in different parts of the world are presented herein.