TITLE:
Chemical Composition, Fluxes and Seasonal Variation of Acid Deposition in Carmen Island, Campeche, Mexico
AUTHORS:
R. M. Cerón, J. G. Cerón, C. G. Carballo, C. A. Aguilar, C. Montalvo, J. A. Benítez, Y. J. Villareal, M. M. Gómez
KEYWORDS:
Trace Elements; Acid Deposition; Deposition Fluxes; Critical Loads; Acid Rain; Campeche; Mexico
JOURNAL NAME:
Journal of Environmental Protection,
Vol.4 No.8A,
August
12,
2013
ABSTRACT: Two hundred and seven rain events from April to
October 2012 were collected in Carmen Island, Campeche, Mexico, and the
concentration of 8 major ions with the pH of the rainwater was analyzed. Chemical composition
variations as a result of seasonal patterns, meteorological conditions, and
mixed local and regional sources contribution were assessed. In spite of the
fact that nitrate and
sulfate levels were higher than background hemispheric values, the average pH values were almost
neutral. Carmen Island was under the influence of both,
local and long-range transported emissions. Chemical composition showed a
dilution effect as a result of the monthly rainfall amount. Ca2+ and
Na+ were the most abundant ions, and these ions acted as acid
neutralizers and buffered the acidity of the rain, suggesting that marine and
crustal aerosols played an important role in the acid-base interactions. Wet
deposition fluxes obtained were compared with reference values proposed as
critical loads, fluxes obtained in this study did not exceed the critical
values reported for sensitive ecosystems in Europe, indicating that this site
has yet enough capacity to support acidity, nitrogen and sulfur deposition.
However, it is necessary to obtain reference values characteristics for
tropical regions.