ForewordW ater has a major importance for the maintenance of life in the planet and, therefore, to talk about the significance of its knowledge, in their several dimensions, is to talk about the survival of the human species, the conservation of the biodiversity balance and the dependence relations among living creatures and natural environments.the presence or absence of water writes history, creates cultures and habits, determines the occupation of territories, wins battles, ends and provides life to the species, determines the future of generations. our planet wouldn't have become a proper environment for life without water. since its origin, the elements hydrogen and oxygen combined to originate the key element of life's existence.under a privileged condition, it enabled the species to evolve and man to exist and to live in this planet. throughout thousands of years, our species occupied territories, grew and developed based on such an important and valuable natural good which is water. However, throughout history, there were changes in the relationship between man and nature and, as a result, in his relationship with water.In the society where we live, water started to be seen as a hydric resource and no longer as a natural good, available for human existence and that of the other species. We started to use it in an indiscriminate manner, always finding new uses, without assessing the environmental consequences in relation to the quantity and quality of water.Besides the population growth in global scale in the last century, the intensity of the shortage increased in certain regions of the planet, mainly due to human factors related to the occupation of land, pollution and the contamination of both the superficial and the underground bodies of water.
