 |
 |
|
Considering the data for all the rivers at the 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 Southeast Asia have recorded higher nitrate concentrations. |
A comparison of the major watersheds between the two decades showed that Northern Europe and North America had lower phosphate concentrations, while the Ganges and Brahmaputra watersheds in South Central Asia had higher concentrations. Nutrient control programmes in municipal and agricultural activities may be key factors in the observed reductions in phosphate concentrations. |
