3.4.2 Ecological changes
Creation of a reservoir produces ecological changes not only to the area of the reservoir itself, by destroying the natural vegetation, but also upstream and downstream of the reservoir. The gradient of a river upstream of a reservoir may be reduced, so the water will slow down, changing the character of the river, causing deposition of sediment, and changes to the natural vegetation and animal life. Downstream of the reservoir the discharge will change, as well as the sediment load, also affecting the plants and animals. For example, annual flooding may cease.