Abstract:
Eutrophication of lakes and seas with algae blooms,
changes in fish stocks and deteriorating swimming
water has been a severe environmental problem in
Sweden for many years. The reason for this is the
increased nutrient losses from arable land due to
intensive agriculture, but also the to man-made changes
of the hydrology and landscape, particularly during the
past two centuries. Community development with the
expansion of settlements and roads, and the
rationalization of agriculture and forestry, among other
things had a major impact on our water and wetland
habitats. The area of wetlands has been drastically
reduced, lakes have been lowered or drained, and many
streams have deepened, straightened or put in tubes.
The water is efficiently transported out of the
catchment, which implies a decrease of the natural
retention capacity of nutrients and an increase of
nutrient loads to lakes and the sea. This has also resulted
in a drastic loss of biodiversity as many wetland
dependent plant and animal species have disappeared.
Also the accessibility of areas for human recreation and
outdoor activities has declined.
