Industrialisation and urbanisation have led to the rapid deterioration in the water quality of rivers, lakes and reservoirs. Heavy metal pollution in aquatic ecosystems has become the most important point for discussion in recent years. The problem of heavy metal pollution is emerging as a matter of concern at local, regional and also at global scales. Heavy metal pollution in aquatic ecosystems pose serious threats to aquatic biodiversity, and drinking of contaminated water pose severe health hazards in humans. Therefore, the focus of attention has been shifted from mere monitoring of environmental conditions to the development of alternative means to solve the environmental problems at local and global levels. This new book discusses how economic aspects and side effects of conventional treatment technologies in aquatic ecosystems paved way to phytoremediation technology.