Rivers are also at the forefront of climate change impacts. Changing precipitation patterns and melting glaciers from climate change both increase peak river discharge and reduce extreme low water flows. This increases flood risk and salinisation in the deltas, reduces freshwater supply, and can hamper navigation conditions. This combination of factors is severely damaging rivers and leaving the ecosystems and human populations dependent upon them vulnerable. Rivers such as the Po and Mississippi, have recently experienced severe drought threatening food production, navigation, and causing negative impact on fisheries. The recent example from Pakistan of excessive flooding is now not the exception but the norm.
The consequence of these changes to rivers, including climate-driven impacts, has been an alarming loss of freshwater biodiversity and a reduction in the ability of these systems to provide important services to humans and to function as the natural lifeblood of the landscape. While occupying only 0.8% of the Earth’s surface, rivers and deltas are immensely important to humanity and sustainability. They provide water, fish, fertile soils, transportation routes and energy for humankind, and host around 40% of all described fish species.
Over 1/3 of the world’s freshwater biodiversity is threatened from extinction. Over 50% of all fish species are found in
rivers. The recent Living Planet report has noted that monitored freshwater species populations have suffered an 83% fall
since 1970. This loss of freshwater biodiversity and natural river habitats impedes our efforts to achieve sustainable development. In fact, there can be not sustainable development without healthy rivers.