Show simple item record

dc.contributor.authorMcGlue, Michael M.
dc.contributor.authorSilva, Aguinaldo
dc.contributor.authorCorradini, Fabricio A.
dc.contributor.authorZani, Hiran
dc.contributor.authorTrees, Mark A.
dc.contributor.authorEllis, Geoffrey S.
dc.contributor.authorParolin, Mauro
dc.contributor.authorSwarzenski, Peter W.
dc.contributor.authorCohen, Andrew S.
dc.contributor.authorAssine, Mario L. [UNESP]
dc.identifier.citationJournal of Paleolimnology. Dordrecht: Springer, v. 46, n. 2, p. 273-289, 2011.
dc.description.abstractSediment records from floodplain lakes have a large and commonly untapped potential for inferring wetland response to global change. The Brazilian Pantanal is a vast, seasonally inundated savanna floodplain system controlled by the flood pulse of the Upper Paraguay River. Little is known, however, about how floodplain lakes within the Pantanal act as sedimentary basins, or what influence hydroclimatic variables exert on limnogeological processes. This knowledge gap was addressed through an actualistic analysis of three large, shallow (< 5 m) floodplain lakes in the western Pantanal: Lagoa Gaiva, Lagoa Mandior, and Baia Vermelha. The lakes are dilute (CO(3) (2-) > Si(4+) > Ca(2+)), mildly alkaline, freshwater systems, the chemistries and morphometrics of which evolve with seasonal flooding. Lake sills are bathymetric shoals marked by siliciclastic fans and marsh vegetation. Flows at the sills likely undergo seasonal reversals with the changing stage of the Upper Paraguay River. Deposition in deeper waters, typically encountered in proximity to margin-coincident topography, is dominated by reduced silty-clays with abundant siliceous microfossils and organic matter. Stable isotopes of carbon and nitrogen, plus hydrogen index measured on bulk organic matter, suggest that contributions from algae (including cyanobacteria) and other C(3)-vegetation dominate in these environments. The presence of lotic sponge spicules, together with patterns of terrigenous sand deposition and geochemical indicators of productivity, points to the importance of the flood pulse for sediment and nutrient delivery to the lakes. Flood-pulse plumes, waves and bioturbation likewise affect the continuity of sedimentation. Short-lived radioisotopes indicate rates of 0.11-0.24 cm year(-1) at sites of uninterrupted deposition. A conceptual facies model, developed from insights gained from modern seasonal processes, can be used to predict limnogeological change when the lakes become isolated on the floodplain or during intervals associated with a strengthened flood pulse. Amplification of the seasonal cycle over longer time scales suggests carbonate, sandy lowstand fan and terrestrial organic matter deposition during arid periods, whereas deposition of lotic sponges, mixed aquatic organic matter, and highstand deltas characterizes wet intervals. The results hold substantial value for interpreting paleolimnological records from floodplain lakes linked to large tropical rivers with annual flooding cycles.en
dc.description.sponsorshipAmerican Chemical Society (ACS)
dc.description.sponsorshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
dc.description.sponsorshipUA-Exxon Mobil COSA
dc.description.sponsorshipChevron Corporation
dc.description.sponsorshipKartchner Caverns
dc.description.sponsorshipEmpresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
dc.description.sponsorshipUFMS-Campus do Pantanal
dc.description.sponsorshipFazenda Santa Teresa and the citizens of Amolar (MS-Brazil)
dc.relation.ispartofJournal of Paleolimnology
dc.sourceWeb of Science
dc.subjectFloodplain lakesen
dc.subjectTropical wetlandsen
dc.subjectSedimentary organic matteren
dc.subjectFreshwater spongesen
dc.titleLimnogeology in Brazil's "forgotten wilderness": a synthesis from the large floodplain lakes of the Pantanalen
dc.contributor.institutionUniversity of Arizona
dc.contributor.institutionUniversidade Federal de Mato Grosso do Sul (UFMS)
dc.contributor.institutionUniversidade Federal do Pará (UFPA)
dc.contributor.institutionInstituto Nacional de Pesquisas Espaciais (INPE)
dc.contributor.institutionUS Geol Survey
dc.contributor.institutionFac Estadual Ciencias & Letras Campo Mourao
dc.contributor.institutionUniversidade Estadual Paulista (UNESP)
dc.description.affiliationUniv Arizona, Dept Geosci, Tucson, AZ 85721 USA
dc.description.affiliationUniv Fed Mato Grosso Sul UFMS CPAN, Dept Ciencias Ambiente, BR-79304902 Corumba, MS, Brazil
dc.description.affiliationUniv Fed Para UFPA, Fac Geog, BR-68501970 Maraba, PA, Brazil
dc.description.affiliationInst Nacl Pesquisas Espaciais INPE, Div Sensoriamento Remoto, BR-12201970 Sao Jose Dos Campos, SP, Brazil
dc.description.affiliationUS Geol Survey, Energy Resources Program, Denver, CO 80225 USA
dc.description.affiliationFac Estadual Ciencias & Letras Campo Mourao, BR-87303100 Campo Mourao, PR, Brazil
dc.description.affiliationUS Geol Survey, Santa Cruz, CA USA
dc.description.affiliationUniv Estadual Paulista UNESP, Dept Geol Aplicada IGCE, BR-13506900 Rio Claro, SP, Brazil
dc.description.affiliationUnespUniv Estadual Paulista UNESP, Dept Geol Aplicada IGCE, BR-13506900 Rio Claro, SP, Brazil
dc.rights.accessRightsAcesso restrito
dc.description.sponsorshipIdACS: 45910-AC8
dc.description.sponsorshipIdFAPESP: 07/55987-3
unesp.campusUniversidade Estadual Paulista (UNESP), Instituto de Geociências e Ciências Exatas, Rio Claropt
Localize o texto completo

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record