Large portions of the region are still in the process of being occupied by humankind and developed, thus providing new opportunities for sustainable development. In addition to being the source of the region's water supply, they prevent and regulate floods, prevent saline water intrusion, ameliorate erosion impacts by retaining sediments, provide nutrient retention and toxicant removal, offer micro-climate stabilization, act as a global carbon sink, serve as a means of transport and are excellent sites for tourism. Much of what freshwater ecosystems provide, including forest, wildlife, fisheries, forage, agricultural and energy resources, is available for human use. For example, the use of genes from wild species occurring in wetlands is an important way of improving cultivated varieties of plants. The value of these products is often measured in millions of dollars annually for any given locality, representing an important source of income for rural and urban communities alike.
Some wetlands also have social, cultural and historical significance.
Despite their importance, many freshwater ecosystems are frequently considered useless. Widespread ignorance about their importance has contributed to this notion and has promoted their destruction and degradation. Conservation of freshwater biodiversity has been seriously neglected throughout the world, and entire ecosystems are threatened with extinction. The primary cause of resource loss is habitat alteration, fueled by rapid population growth and unwise development, both planned and unplanned. Erosion and deforestation of the catchment basin forests has reached dramatic intensity along the eastern slopes of the Andes, from Colombia to northern Argentina.