Nutrient Balance Assessment in the Mekong Basin: Nitrogen and Phosphorus Dynamics in a Catchment Scale

Abstract

Tropical regions are typically rather poorly covered by nutrient enrichment information, despite th eir soaring population, urbanization, industrialization, and intensifying agriculture. We provide an overview of nutrient fluxes and their temporal and spatial patterns in the Mekong River for 1985–2005. Total inorganic nitrogen fluxes increased significantly, while phosphorus fluxes increased less steeply. The majority of fluxes originated from agricultural and from forest and shrubland areas. Although the Mekong is not yet facing severe water quality problems, the concurrent rapid development can be expected to accelerate nutrient enrichment. There is thus an urgent need to improve water quality monitoring and pollution control measures, and to give water quality issues more weight at the policy level.

Acknowledgements

The authors are grateful to colleagues at the Water & Development Research Group at our home institution for their thoughtful comments and inspiration. This work received funding from the Maa- ja vesitekniikan tuki ry (Soil and Water Technology Foundation) and from the Academy of Finland (Project 133748). Matti Kummu also received funding from the postdoctoral funds of Aalto University.