Global Anthropogenic Phosphorus Loads to Freshwater and Associated Grey Water Footprints and Water Pollution Levels: A High-Resolution Global Study

Authors

• Mesfin Mekonnen, University of Nebraska - LincolnFollow
• Arjen Y. Hoekstra, University of Twente & National University of Singapore

ORCID IDs

http://orcid.org/0000-0002-3573-9759

http://orcid.org/0000-0002-4769-5239

Date of this Version

1-24-2018

Document Type

Article

Citation

Mekonnen, M. M., , & Hoekstra, A. Y. (2018). Global anthropogenic phosphorus loads to freshwater and associated grey water footprints and water pollution levels: A high- resolution global study. Water Resources Research, 54, 345–358. https://doi.org/10.1002/ 2017WR020448

Abstract

We estimate the global anthropogenic phosphorus (P) loads to freshwater and the associated grey water footprints (GWFs) for the period 2002–2010, at a spatial resolution of 5 3 5 arc min, and com- pare the GWF per river basin to runoff to assess the P-related water pollution level (WPL). The global anthro- pogenic P load to freshwater systems from both diffuse and point sources is estimated at 1.5 Tg/yr. More than half of this total load was in Asia, followed by Europe (19%) and Latin America and the Caribbean (13%). The domestic sector contributed 54% to the total, agriculture 38%, and industry 8%. In agriculture, cereals production had the largest contribution to the P load (31%), followed by fruits, vegetables, and oil crops, each contributing 15%. The global total GWF related to anthropogenic P loads is estimated to be 147 3 1012 m3/yr, with China contributing 30%, India 8%, USA 7%, and Spain and Brazil 6% each. The basins with WPL > 1 (where GWF exceeds the basin’s assimilation capacity) together cover about 38% of the global land area, 37% of the global river discharge, and provide residence to about 90% of the global population.