Climate change and stream water quality in the multi-factor context

Abstract

Availability of fresh water of adequate quantity and quality is essential to life. Water quality problems turn up as a result of both intensive land use and intensive water use by people. Rivers have been treated worldwide as a convenient recipient of waste that was subsequently transported to the sea. As a result, rivers, lakes and coastal zones became polluted, with harmful consequences for biota and human health, and reduction of the biodiversity of many rivers and water bodies. Besides, due to close linkage of climatic and freshwater systems, water quality is influenced by many climatic factors, such as air and water temperature, precipitation and occurrence of extreme events. Many different water pollutants can be distinguished, such as nutrients, heavy metals, toxic organic pollutants and pathogens. Sources of water pollution are either point or diffuse. The former are represented by easily identifiable, lumped inputs, such as a pipe, where polluted water is discharged to a water body. Much of industrial and municipal wastewaters are discharged to rivers in this way, either with or without treatment. At present, despite improvements in some regions, water pollution is on