『Abstract
　The total iron (TFe) concentrations in five rivers to a Galician Ria (averages 10.-4.5 μM) was within the pristine range, but in rainwater it was higher (14μM). TFe values of small sewage treatment plants (STP) ranged between 3 and 4μM, whereas in the largest was 11μM. Particulate iron in rivers was five times more abundant than dissolved iron, except in the Lagares where it was 20 times higher, but in the STDs the dissolved/particulate coefficients varied from 0.1 to 1.1 and in the rainwater it was lower than 0.4. Equations of water flow versus iron flux were obtained to quantify the iron contribution from the freshwater sources to the Vigo Ria. It receives annually 490 tons of iron (6％ in dissolved form) and 90％ of this comes from industries focused on metal processes. The contaminated Lagares River accounts for the main input of TFe (327 t a^-1), followed by rainwater (78 t a^-1), the Oitaven（eの頭に´） River (28 t a^-1) and Vigo STP (33 t a^-1). Anthropogenic activities have increased the amount of iron flowing into the Ria by roughly ten times and this could upset the biogeochemical cycle in similar coastal systems.

Keywords: Dissolved; Freshwater; Iron; NW Spain; Particulate』

Introduction
　Study site
Materials and methods
Results
　Iron concentration in waters
　Freshwater iron fluxes
Discussion
　Natural sources of iron in the freshwater flowing into the Ria
　Low anthropogenic enriched sources of iron in the freshwater flowing into the Ria
　High anthropogenic enriched sources of iron in the freshwater flowing into the Ria
Conclusion
Acknowledgements
References