Using this graphic and referring to it is encouraged, and please use it in presentations, web pages, newspapers, blogs and reports.
For any form of publication, please include the link to this page and give the cartographer/designer credit (in this case Philippe Rekacewicz)
United Nations Environment Programme (UNEP) - Global Environment Monitoring System (GEMS), Freshwater Quality Programme, United Nations Environment Programme (UNEP), 2001; National Water Research Institute Environment Canada, Ontario, 2001.
Uploaded on Thursday 16 Feb 2012
Nitrate levels: concentrations at river mouths
Nutrients are essential to life. In aquatic systems, nitrogen and phosphorus are the two nutrients that most commonly control the growth of aquatic plants, algae and bacteria. Nitrogen and phosphorus are considered to be the primary drivers of eutrophication of aquatic ecosystems, where increased nutrient concentrations lead to increased primary productivity. Some systems are naturally eutrophic, whereas others have become eutrophic as a result of human activity, such as runoff from agricultural areas and the discharge of municipal waste into rivers and lakes.
Considering the data for all the rivers at a continental level, there has been little change in nitrate (NO3-N) concentrations between the two decades under comparison. Changes in the median value were not statistically significant.
European rivers showed the highest nitrate loads transported to the marine environment. Comparing data from the two decades, North American and European rivers have remained fairly stable, while major river basins in south-central and south-east Asia have recorded higher nitrate concentrations.
Municipal waste (12)
, Productivity (35)
, Nitrate (8)
, Eutrophication (14)
, Lead (40)
, Nitrogen (21)
, Phosphorus (6)
, Marine environment (12)
, Runoff (25)
, Nutrient (26)
, River (110)