BUSTAMANTE, M. M. C.

CHAVES, J.

FIGUEIREDO, R. de O.

JOHNSON, M. S.

KRUSCHE, A. V.

LAMON III, E. C.

MARKEWITZ, D.

NEILL, C.

SILVA, J. S. O.

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  Search  Print PageBrowse by DayBrowse by AuthorBrowse by ProgramMeeting Home96th ESA Annual MeetingESA HomeCOS 97-6 - Discharge–calcium concentration relationships in streams of theAmazon and Cerrado of Brazil: Soil or land use controlledThursday, August 11, 2011: 9:50 AM12B, Austin Convention CenterDaniel Markewitz , Warnell School of Forestry and Natural Resources, The University of Georgia, Athens, GAE. Conrad Lamon III , Statistical Ecology Associates LLC, Canyon Lake, TXMercedes MMC Bustamante , Universidade de Brasilia, Brasilia, BrazilJoaquin Chaves , Brown UniversityRicardo O. Figueiredo , Embrapa Meio Ambiente, Jaguariúna, BrazilMark S. Johnson , Institute for Resources, Environment, and Sustainability, University of British Columbia, Vancouver,BC, CanadaAlex V. Krusche , Laboratório Ecologia Isotópica, CENA/USPChristopher Neill , Ecosystems Center, Marine Biological Laboratory, Woods Hole, MAJosé S. O. Silva , Department of Ecology, Universidade de Brasilia, Brasilia, BrazilBackground/Question/MethodsStream discharge-concentration relationships are indicators of terrestrial ecosystem function. Throughout the Amazonand Cerrado regions of Brazil rapid changes in land use and land cover may be altering these hydrochemicalrelationships.  The current analysis focuses on factors controlling the discharge-calcium (Ca) concentration relationshipsince previous research in these regions has demonstrated both positive and negative slopes in linear log10discharge-log10Ca concentration regressions.  The objective of the current study was to evaluate potential factors controllingstream discharge-Ca concentration relationships including year, season, stream order, vegetation cover, land use, andsoil classification.  It was hypothesized that land use and soil class are the most critical attributes controllingdischarge-Ca concentration relationships. A multilevel, linear regression approach was utilized with data from 51stations on 28 streams throughout Brazil.  These streams come from three distinct regions and varied broadly inwatershed size (<1 to >106 ha) and discharge (10-5.7 to 103.2 m3 sec-1).  Results/ConclusionsLinear regressions of log10Ca versus log10 discharge in 13 gauged streams have a preponderance of negative slopeswith only two streams having significant positive slopes.  A multilevel model based ANOVA decomposition suggests theeffect of discharge on Ca concentration is large but variable.  Vegetation cover, which incorporates aspects of land use,explains the largest proportion of the variance in the effect of discharge on Ca (slope) followed by season and year.   Incontrast, stream order, land use, and soil class explain most of the variation in stream Ca concentration (intercept). Inthe current data set, soil class, which is related to lithology, has an important effect on Ca concentration but land use,likely through its effect on runoff concentration and hydrology, has a greater effect on discharge-concentrationrelationships.  The multilevel model for the discharge concentration relationship, in concert with a multilevel model fordischarge in locations without gauges allowed assessment of slope sign (+/-) at all 51 stations.See more of: StatisticsSee more of: Contributed Oral Papers1990 M STREET, NW | SUITE 700 | WASHINGTON, DC 20036 | PHONE 202-833-8773 | FAX 202-833-8775 | EMAIL ESAHQ AT ESA.ORGCopyright © . All rights reserved.Banner photo by Flickr user greg westfall.<< Previous Abstract | Next Abstract >>96th ESA Annual Meeting (August 7 -- 12, 2011) http://eco.confex.com/eco/2011/webprogram/Paper30803.html1 de 1 1/3/2012 16:42ERROR: syntaxerrorOFFENDING COMMAND: --nostringval--STACK:/Title ()/Subject (D:20120301164245-03’00’)/ModDate ()/Keywords (PDFCreator Version 0.9.5)/Creator (D:20120301164245-03’00’)/CreationDate (Gutzlaff)/Author -mark- 

Discharge calcium concentration relationships in streams of the Amazon and Cerrado of Brazil: soil or land use controlled.

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http://www.alice.cnptia.embrapa.br/alice/bitstream/doc/919663/1/2011RA099.pdf

Discharge calcium concentration relationships in streams of the Amazon and Cerrado of Brazil: soil or land use controlled.

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