H43B-1479
Influence of land use on the hydrobiogeochemistry of the Camanducaia and Jaguari watersheds, Brazil
Thursday, 17 December 2015
Poster Hall (Moscone South)
Cristiane Formigosa Gadelha da Costa1, Ricardo de Oliveira Figueiredo2, Plinio Barbosa de Camargo3, Marisa C Piccolo4, Edmar Antonio Mazzi5, Lucas de Camargo Reis6, Maria Lucia Zuccari2, Timothy R Green7 and Vera Lucia Ferracini2, (1)CENA Center for Nuclear Energy in Agriculture, Piracicaba, Brazil, (2)EMBRAPA Brazilian Agricultural Research Corportation, Embrapa Meio Ambiente, Campinas, Brazil, (3)University of Sao Paulo, Sao Paulo, United States, (4)Universidade de São Paulo, CENA, Piracicaba, Brazil, (5)Universidade de Sao Paulo, Piracicaba, Brazil, (6)Universidade de São Paulo, São Paulo, Brazil, (7)USDA ARS, Pendleton, OR, United States
Abstract:
Two medium-sized watersheds of the Piracicaba river basin, the Camanducaia and Jaguari sub-basins, are being studied to evaluate the effects of land use change on the basin’s hydrobiogeochemistry. The Jaguari basin is an important provider the Cantareira reservoir system that supplies around six million inhabitants of the Metropolitan Region of São Paulo, Brazil. A one-year hydrological study began on January 2015 to monitor some water quality parameters such as pH, electric conductivity (EC), dissolved oxygen (DO), dissolved organic and inorganic carbon (DOC and DIC), nitrate (NO3-), ammonium (NH4+) and total nitrogen (TN). For that purpose we established 19 sampling stations along the Camanducaia (8 stations) and Jaguari (11 stations) river channels; two stations at their main tributaries Mosquito and Camanducaia Mineiro, respectively; and another two stations at small streams in headwater areas of the Jaguari and Camanducaia watersheds. Preliminary results show that DOC concentrations are correlated DIC (r=0.81 at Jaguari; r=0.70 at Camanducaia; p <0.05). We observe that DOC tends to increase by multiples of 2.5 and 3.5 times from forested headwater areas to the most downstream stations of Jaguari and Camanducaia, respectively. Regarding DIC these multiples are 4.4 and 1.9 times greater. The four most downstream stations at Jaguari show urban area effects with higher DIC monthly values ranging from 28.7 to 33 mg L-1. Also DIC correlated with EC values (means around 160 µS) at two of these stations. We expect that at the end of this monitoring year results will show stronger relations between hydrobiogeochemical parameters and land use change.
