Effect of Water pollution on Ecosystems

Water pollution can severely affect or outright destroy ecosystems, especially aquatic ones. Two distinct ecosystem-level effects are described. First, destruction of ecosystems: pollutants affect the niches and habitats organisms depend on and threaten their survival directly; soil fertility can also be affected where water pollution reaches land, making the system progressively uninhabitable. Second, disruption of food chains: water pollution disrupts natural food chains and food webs directly. Pollutants such as lead and cadmium are taken up by primary consumers, where they can be immediately lethal or simply get stored in tissue; when these primary consumers are then eaten by secondary consumers, the food chain can be disrupted at any trophic level, or the pollutant's concentration can become progressively enhanced as it passes up the chain -- the biomagnification process covered in detail later in the chapter. A further ecosystem-scale effect noted here is thermal: hot water released fr …