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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Rainwater chemistry and bulk atmospheric deposition in a tropical semiarid ecosystem: the Brazilian Caatinga

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Deusdara, K. R. L. ; Forti, M. C. ; Borma, L. S. ; Menezes, R. S. C. ; Lima, J. R. S. ; Ometto, J. P. H. B.
Total Authors: 6
Document type: Journal article
Source: Journal of Atmospheric Chemistry; v. 74, n. 1, p. 71-85, MAR 2017.
Web of Science Citations: 3

We assessed the rainwater chemistry, the potential sources of its main inorganic components and bulk atmospheric deposition in a rural tropical semiarid region in the Brazilian Caatinga. Rainfall samples were collected during two wet seasons, one during an extremely dry year (2012) and one during a year with normal rainfall (2013). According to measurements of the main inorganic ions in the rainwater (H+, Na+, NH4 (+), K+, Ca2+, Mg2+, Cl-, NO3 (-), and SO4 (2-)), no differences were observed in the total ionic charge between the two investigated wet seasons. However, Ca2+, K+, NH4 (+) and NO3 (-) were significant higher in the wetter year (p < 0.05) which was attributed to anthropogenic activities, such as organic fertilizer applications. The total ionic contents of the rainwater suggested a dominant marine contribution, accounting for 76 % and 58 % of the rainwater in 2012 and 2013, respectively. The sum of the non-sea-salt fractions of Cl-, SO4 (2-), Mg2+, Ca2+ and K+ were 19 % and 33 % in 2012 and 2013, and the nitrogenous compounds accounted for 2.8 % and 6.0 % of the total ionic contents in 2012 and 2013, respectively. The ionic ratios suggested that Mg2+ was probably the main neutralizing constituent of rainwater acidity, followed by Ca2+. We observed a low bulk atmospheric deposition of all major rainwater ions during both wet seasons. Regarding nitrogen deposition, we estimated slightly lower annual inputs than previous global estimates. Our findings contribute to the understanding of rainfall chemistry in northeastern Brazil by providing baseline information for a previously unstudied tropical semiarid ecosystem. (AU)

FAPESP's process: 12/01138-3 - Hydro-climatic conditions and dynamic response of nitrogen and carbon in an area of caatinga, Pernambuco
Grantee:Karinne Reis Deusdará Leal
Support Opportunities: Scholarships in Brazil - Doctorate
FAPESP's process: 09/52468-0 - Climate change impacts on the land cover and use in Pernambuco: data generation to subside public decisions
Grantee:Jean Pierre Henry Balbaud Ometto
Support Opportunities: Research Program on Global Climate Change - Thematic Grants