J Paleolimnol (2011) 46:273–289
DOI 10.1007/s10933-011-9538-5
ORIGINAL PAPER
Limnogeology in Brazil’s ‘‘forgotten wilderness’’:
a synthesis from the large floodplain lakes of the Pantanal
Michael M. McGlue • Aguinaldo Silva • Fabrı́cio A. Corradini • Hiran Zani
Mark A. Trees • Geoffrey S. Ellis • Mauro Parolin • Peter W. Swarzenski •
Andrew S. Cohen • Mario L. Assine
•
Received: 17 March 2011 / Accepted: 27 June 2011 / Published online: 13 July 2011
! Springer Science+Business Media B.V. 2011
Abstract Sediment 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
Electronic supplementary material The online version of
this article (doi:10.1007/s10933-011-9538-5) contains
supplementary material, which is available to authorized users.
M. M. McGlue (&) ! M. A. Trees ! A. S. Cohen
Department of Geosciences, The University of Arizona,
1040 East 4th Street, Tucson, AZ 85721, USA
e-mail: mmmcglue@email.arizona.edu
M. A. Trees
e-mail: treesma@email.arizona.edu
A. S. Cohen
e-mail: cohen@email.arizona.edu
A. Silva
Departamento de Ciências do Ambiente, Universidade
Federal de Mato Grosso do Sul—UFMS-CPAN, Av. Rio
Branco, 1270, Corumbá, MS 79304-902, Brazil
e-mail: aguinald_silva@yahoo.com.br
F. A. Corradini
Faculdade de Geografia, Universidade Federal do ParáUFPA, Folha 31, Quadra 7, Lote Especial S/N, Marabá,
PA 68501-970, Brazil
e-mail: f_coradini@yahoo.com.br
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 Gaı́va,
G. S. Ellis
Energy Resources Program, U.S. Geological Survey,
Denver, CO, USA
e-mail: gsellis@usgs.gov
M. Parolin
Faculdade Estadual de Ciências e Letras de Campo
Mourão, Av. Comendador Norberto Marcondes, 733,
Campo Mourão, PR 87303-100, Brazil
e-mail: mauroparolin@gmail.com
P. W. Swarzenski
U.S. Geological Survey, Santa Cruz, CA, USA
e-mail: pswarzen@usgs.gov
M. L. Assine
Departamento de Geologia Aplicada—IGCE,
Universidade Estadual Paulista—UNESP/Campus Rio
Claro, Av. 24-A, 1515, Rio Claro, SP 13506-900, Brazil
e-mail: assine@rc.unesp.br
H. Zani
Divisão de Sensoriamento Remoto, Instituto Nacional de
Pesquisas Espaciais—INPE, Av. dos Astronautas, 1758,
São José dos Campos, SP 12201-970, Brazil
e-mail: hzani@dsr.inpe.br
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Lagoa Mandioré and Baia Vermelha. The lakes are
dilute (CO32- [ Si4? [ Ca2?), 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 C3-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.
Keywords Pantanal ! Limnogeology ! Floodplain
lakes ! Tropical wetlands ! Sedimentary organic
matter ! Freshwater sponges
Introduction
Global estimates indicate that the total land surface
area occupied by wetlands in the humid tropics and
subtropics exceeds 3.3 9 106 km2 (Maltby and
Turner 1983). Prior to the twentieth century, attitudes
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J Paleolimnol (2011) 46:273–289
towards such wetlands were largely negative, fueled
by the desire to reclaim perennially-inundated lands
for agriculture or industry (Mitsch and Gosselink
2000). More recently, international efforts have
demonstrated the value of wetlands conservation,
especially for the protection of numerous aquatic
species and for maintaining hydrologic resources
critical to downstream human populations. Importantly, vast tropical wetlands are now recognized for
the unique role they play in global biogeochemical
cycles, particularly in the production and sequestration of greenhouse gases (Bartlett and Harriss 1993;
Cao et al. 1998; Mitsch et al. 2009). Global changes
in air temperature or increased variability in the water
cycle, such as those predicted by the IPCC AR4, are
thought to place wetland ecotones at substantial risk
for terrestrialisation (Chauhan and Gopal 2001; Bates
et al. 2008). Few in-depth paleo-records from unaltered, tropical wetlands are available, however, to
assess the response of these sensitive systems to wellknown climatic perturbations of the Quaternary
(Donders et al. 2005).
Stratigraphic sequences from large lakes in the
Pantanal may provide a unique lens through which
the response of tropical wetlands to environmental
change can be viewed (Fig. 1). The Pantanal is the
world’s largest freshwater wetland and the hydrologic
basin of the Upper Paraguay River (PR; Heckman
1998). Scientific inquiry into the region was delayed
until the twentieth century, as early attempts at
exploration were deterred by harsh conditions along
the Brazilian frontier (Por 1995). Sixteenth-century
maps depicted the Pantanal as a single large lake,
purportedly because of reports given to Spanish
conquistadors by lakeshore-dwelling Indians (Por
1995). Surveying conducted centuries later revealed
that thousands of lakes dot the Pantanal landscape
(Ab’Saber 1988; Assine and Soares 2004). Limnogeological datasets from the Pantanal are, however,
generally absent, constraining an understanding of
the lakes and their linkages to the PR floodplain.
The purpose of this study is to provide the first
synthesis of modern limnogeological knowledge on
three lakes situated along the floodplain of the PR:
Lagoa Gaı́va, Lagoa Mandioré and Baia Vermelha
(Fig. 1B). Several research groups noted the potentially valuable archive of paleoclimate information
stored within deposits from these and nearby floodplain lakes (Mayle et al. 2004; de Oliveira Bezerra
J Paleolimnol (2011) 46:273–289
275
Fig. 1 A = Regional map of the Brazilian Pantanal, the
world’s largest neotropical wetland and the hydrological basin
of the Upper Paraguay River (adapted from Assine and Silva
2009). Ten large perennial lakes mark the western floodplain of
this river, straddling the border of Brazil and Bolivia. The
rectangle outlines the area of B. B = LANDSAT (2000) image
showing the position of LG, LM, and BV with respect to the
main channel of the PR and the highlands of the Serras do
Amolar. C = bathymetric map and sample grid for LG;
sediment core locations are marked with stars. D = bathymetric map and sample grid for LM. Heavy red lines indicate the
location of high-relief lake margins and rocky shorelines;
orange lines mark sand bars. E = bathymetric map and sample
grid for BV
and Mozeto 2008). Inferences from lake sediment
may likewise be vital for understanding more recent
environmental dynamics in the greater Pantanal. As
tropical wetlands are ecologically sensitive, such
information holds considerable value for conservation and sustainability planning. Before longer sediment core-based reconstructions can be fully
realized, a number of key questions need to be
addressed, including: How do these lakes act as
depositional basins? What are the dominant limnological processes that influence patterns of sedimentation? What baseline variability exists in the
geochemistry of organic matter in modern lake
sediments? What relationships exist between the
lakes and the greater Pantanal wetland system? The
focus of this study is to address these questions using
observations and data acquired from the lakes from
2007 to 2009.
et al. 1988; Por 1995). Estimates from remote sensing
indicate that the surface area of the Pantanal that is
inundated at maximum flood conditions exceeds
130,000 km2 (Hamilton et al. 2002). The region is
particularly renowned for the biodiversity of its flora
and for its role as a natural wildlife sanctuary,
especially for numerous species of fish and aquatic
birds (Heckman 1998; Junk et al. 2006; Lopes et al.
2007). Vegetation is a mosaic of cerrado (tropical
savanna), Amazon-derived semi-deciduous forest,
Chaco-derived seasonal dry forest and aquatic plants
(Cole 1960; Prance and Schaller 1982). The spatial
distribution of plant communities is heterogeneous and
controlled dominantly by patterns of seasonal flooding, topography and soil type (Pinder and Rosso 1998).
Lagoa Gaı́va (LG), Lagoa Mandioré (LM) and Baia
Vermelha (BV) are located along the western margin
of the PR (Fig. 1). The lakes are amongst the largest
perennial standing bodies of water in the Pantanal and
its Paraguai-Corixo Grande sub-region (Electronic
Supplementary Material Table 1; de Magalhães
1992). The lakes are interspersed within the Serra do
Amolar, a mountain range with[800 m of local relief.
Site description
The Pantanal (16–20"S, 55–58"W) straddles the
borders of Brazil, Bolivia and Paraguay (Fig. 1; Alho
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Geology
The Pantanal sits in a low-altitude (mean elevation
\200 m above sea level), elliptically-shaped, seismically-active basin (Fig. 1; Assine and Soares
2004). Andean tectonics are generally invoked to
explain the presence of the Pantanal basin, although
its position within the foreland remains equivocal.
Horton and DeCelles (1997) argued that the Pantanal
forms the backbulge depozone of the Modern Andean
foreland basin system. More recent research by Chase
et al. (2010) supports this hypothesis, as geoid
anomalies indicate the presence of a flexural forebulge [200 km west of the Pantanal. In contrast,
Ussami et al. (1999) used geophysical data to suggest
that the Pantanal depression formed through extension, set in motion by the interaction of the Andean
forebulge with the Neoproterozoic Paraguai foldthrust belt. Regardless of its tectonic origin, at least
500 m of Quaternary sediments fill the Pantanal basin
(Ussami et al. 1999). Although a number of fault
trends are apparent in the basin, the NE-SW-trending
Transbrasiliano Lineament is most significant, as the
course of the PR is strongly altered by its presence in
a number of locations (Assine and Soares 2004).
Several large rivers draining basin-margin highlands
enter the Pantanal, forming expansive, low-gradient
fluvial megafans north and east of the PR (Assine and
Silva 2009). A wide variety of lacustrine environments are present in association with distal megafan
surfaces, including thousands of saline and fresh
ponds in the Nhecolândia region of the southern
Pantanal (Tricart 1982; Barbiéro et al. 2002).
J Paleolimnol (2011) 46:273–289
net annual loss approaching 300 mm (Alfonsi and
Paes de Camargo 1986; Por 1995). A shift in wind
direction accompanies the change in seasons, as
austral summer winds are from the northwest,
whereas winds in the austral winter are dominantly
from the east-northeast. Over the past 40 years, dry
season wind velocities average 5–6 m/s near the
study lakes, whereas wind speeds during the rainy
season are comparatively slower.
Hydrology and limnology
The hydrology of the Pantanal is controlled by the
flooding cycle of the PR, as well as the combination of
precipitation and evapo-transpiration. A particularly
notable aspect of PR’s annual flooding cycle is the
delayed passage of its flood pulse moving from north
to south, altering stage in the main channel by more
than 5 m over the course of several months (Hamilton
et al. 1997). Small tributary channels connect each of
the study lakes to the PR (Fig. 1A, C, D, E). Exchange
between the lakes and the PR is strongest following
the passage of the flood wave, which commonly
occurs several months after peak austral summer
precipitation. Seasonal retention of the flood waters in
the northern Pantanal results from the different
mechanisms of floodplain inundation, including: (1)
overbank flow of the PR and smaller tributaries,
commonly in association with heavy seasonal rainfall;
(2) a backwater effect, where overland flow on
floodplains becomes impeded by the elevated stage
of the PR; and (3) local ponding of rainfall on heavilyvegetated floodplain soils (Hamilton 1999).
Climate
Tropical latitude and seasonal migration of the
Intertropical Convergence Zone (ITCZ) controls
climate patterns in the Pantanal. Mean annual air
temperature in the region is *25"C. Precipitation is
spatially variable and strongly seasonal. Near the
study area, annual precipitation typically exceeds
1,000 mm, whereas precipitation to the north is
greater, but more seasonally variable (Electronic
Supplementary Material Fig. 1). The majority of
precipitation ([70%) falls during a prolonged wet
season that lasts from late October to early April.
Evaporation exceeds precipitation during most of the
year in the Pantanal, with some areas experiencing a
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Materials and methods
Approach
Tropical wetlands typically house a wide variety of
depositional environments that are linked by prevailing climate and the hydrology of large rivers.
Inundation and passage of the PR flood pulse are
key mechanisms controlling floodplain ecological
interactions and productivity in the Pantanal (Junk
et al. 1989; de Oliveira and Calheiros 2000). However, the implications of flood-pulse dynamics for
limnogeological processes represent a key knowledge
J Paleolimnol (2011) 46:273–289
gap for the region. In order to redress this gap, we
undertook an assessment of modern floodplain lakewater chemistry, bathymetry, morphometry, physical
sedimentology and sedimentary biogeochemistry.
Integrated analyses of limnological processes and
their influence on geological products are vital, as
accurate interpretations of paleoenvironments derived
from sediment cores hinges on robust calibration
datasets that validate the meaning and fidelity of
sedimentary proxy data.
We conducted reconnaissance bathymetric and
water sampling surveys in 2007, 2008, and 2009
using a hand-held fathometer. Water chemistry was
determined in situ using a YSI model 85 multi-meter
for dissolved oxygen, conductivity and temperature,
and a Hach Sension1 meter was used to measure pH
(Electronic Supplementary Material Table 2). Major
ions were determined using a Perkin-Elmer Optima
5300 ICP-OES at the University of Arizona.
The upper 2–3 cm of the modern lake floors
(n = 40, 69 and 45 for LG, LM and BV, respectively)
were collected using a Ponar grab-sampler in order to
assess the physical and geochemical attributes of
sediments that have recently accumulated in these
lakes. Sample grids were constructed to provide
maximum coverage of the different environments
encountered in the field. Spacing between individual
sampling stations varied, but in all cases was
\2.5 km. Short (\1.5 m) sediment cores were collected and dated to evaluate rates of sedimentation.
Cores were collected from BV and LM in 2008 and
LG in 2009 using a Livingstone-style square rod corer
or an aluminum-barrel vibracorer system. Sediment
geochronologies and linear sedimentation rates
(cm year-1) were derived for LG cores using the
decay of excess 210Pb (t1/2 = 22.3 year) at the USGS
in Santa Cruz, CA, following the calculations presented in Swarzenski et al. (2006). Precision in the
activity of excess 210Pb was typically better than 10%.
Smear slides were inspected under a petrographic
microscope to estimate sediment components. Concentrations of biogenic silica (BiSi), total organic
carbon (TOC), total nitrogen (TN) and stable isotopes
of C and N were measured to assess productivity and
the composition of organic matter (OM) in the lake
sediments. Biogenic silica analyses were completed
at the University of Minnesota utilizing multiple
extractions of hot alkaline digestions following a
modified protocol of DeMaster (1979). Reported
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values have an analytical precision of *1.0%.
Elemental and stable isotopic analyses of sediment
OM were conducted at the University of Arizona.
Total organic carbon, TN, d13COM, and d15NOM were
measured on a continuous-flow gas-ratio mass spectrometer (Finnigan Delta PlusXL) coupled to a
Costech elemental analyzer. Samples were decarbonated using 1 M HCl at room temperature for 1 h,
washed four times with deionized water, and dried at
40"C prior to combustion in the elemental analyzer.
Standardization is based on acetanilide for elemental
concentration and NBS-22 and USGS-24 for d13Com.
Precision was better than ±0.09 and 0.20 for d13Com
and d15Nom, respectively, based on repeated standard
analyses. d13COM values are given with respect to the
PDB standard and d15NOM values are reported with
respect to air. A select number of decarbonated
samples were analyzed by Rock–Eval pyrolysis at the
University of Houston to further discriminate the
provenance of sediment OM (Espitalie et al. 1977).
Particle size analyses were conducted at the
University of Arizona using a Malvern laser-diffraction analyzer coupled to a Hydro 2000S sample
dispersion bench. Particle size provides key insights
into environmental energy and sedimentation processes (traction flow vs. suspension settling). Samples
were pre-treated according to Johnson and McCave
(2008) to remove BiSi and OM, whereas authigenic
minerals were removed by excess hot 1 M HCl
digestion for 24 h. Following completion of the
digestions, samples were disaggregated using a solution of sodium hexametaphosphate and a mechanical
shaker. Prior to analysis, sediments were examined
optically to ensure the removal of non-terrigenous
particles.
A subset of samples from each lake was processed
for sponge microfossils at the Faculdade Estadual de
Ciências e Letras de Campo Mourão, following the
procedure outlined in Volkmer-Ribeiro and Turcq
(1996). Sample aliquots were suspended in water,
dried on microscopic slides, Entellan-mounted and
permanently sealed with cover slips. Species identification and nomenclature followed Volkmer-Ribeiro
and Pauls (2000) and included: (1) megascleres,
which are spicules that integrate the sponge skeletal
network; (2) microscleres, a smaller spicule within
the sponge skeleton; and (3) gemmoscleres, spicules
that cover the gemmules and which ultimately define
families, genera and species in freshwater sponges.
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Results
Sedimentology and geochemistry
Morphometrics, bathymetry, and water chemistry
Mean siliciclastic particle size trends and the concentrations of BiSi, TOC, and TN vary among LG,
LM and BV (Fig. 2). In LG and LM, dark green silts
and clays are commonly associated with the deepest
areas of the basins, whereas similar sediments in BV
were deposited only west of the headland, where
water depths exceeded 2.5 m. Photomicrographs of
sediment components in these environments are
presented in Electronic Supplementary Material
Fig. 2. Terrigenous grains in the sand fraction
([63 lm) are common in the lakes, especially
proximal to basin sill points. In LG, a broad, sandy
fan emanating from the basin sill occupies the
northern sub-basin (Fig. 2). Likewise, lake floor
substrates at the northern end of the southern subbasin, where the lake receives weak overflow from
Lagoa Uberaba, are dominantly sandy. In LM, axial
margins and cuspate bays are commonly sand-rich
environments. Inflow from the PR at the basin sill
forms a sandy deltaic fan with a surface area
[40 km2, whereas a much smaller sand-rich delta
exists along the northern axis of LM (Fig. 2).
Approximately 3 km offshore from the northern
delta, a 1.5-km-long, partially-vegetated sand bar
creates a pronounced bathymetric shoal; a similar
shoreline-parallel bar exists off a cuspate bay on the
southwestern margin of the lake. Whereas coarsegrained sediment west of the headland in BV is
confined near the shoreline, lake floor sediment east
of the headland is commonly sandy. A northeastoriented, *30-km2, sand-rich fan occupies much of
the center of the basin east of the headland. Along the
eastern lake margin, sandy sediments mark floodpulse connection points with the PR.
Values of BiSi in LG range between 0.0 and 3.5
wt%, with a mean of 1.5 wt% (Electronic Supplementary Material Table 3). Biogenic silica concentrations are highest on the eastern side of southern
LG, where samples exceed 2.5 wt% (Fig. 2). Elsewhere in the basin, lake floor sediment has less BiSi,
with samples generally exhibiting values below 2.0
wt%. Total nitrogen ranges from 0.0 to 0.4 wt%, with
a mean of 0.2 wt%, whereas values of TOC range
from 0.0 to 3.3 wt%, with a mean of 1.5 wt%.
Contours of TN and TOC are simple and concentric
in the southern sub-basin. Geochemical analyses of
OM from LG indicate relatively narrow ranges of
Figure 1 and Electronic Supplementary Material
Tables 1 and 2 present morphometrics, bathymetry
and water chemistry data for LG, LM and BV. The
lakes share a number of limnological characteristics
in common after the passage of the PR flood pulse,
including: (1) dominant CO32- [ Si4? [ Ca2? hydrochemistries; (2) well-oxygenated water columns;
(3) low (freshwater) conductivity values; (4) weaklybasic pH values; (5) elongate basin shapes with fetch
distances \25 km; (6) shallow mean water depths
(\3.5 m); and (7) maximum water depths proximal
to high relief lake margins. Complete thermal
stratification was not detected in any of the lakes,
but confirmation of mixing state awaits future
studies.
Recent satellite imagery indicates that LG has a
surface area of *100 km2 during passage of the
flood. The basin sill is located along the eastern
margin of the northern sub-basin of the lake, at an
altitude of *95 m a.s.l. Proximal to the sill, LG is
very shallow, with water depths B2.5 m at a distance
of *2 km from shore (Fig. 1C). A bathymetric low
exists \3 km from the eastern high-relief margin of
the southern sub-basin; water depths were routinely
[4.5 m in this area. Lagoa Mandioré has a surface
area [150 km2 during the passage of the flood pulse.
The basin sill is on the southeastern lake margin at an
altitude of *93 m a.s.l. Water depths generally
increase with distance from the shoreline in LM. An
exception to this trend occurs\1 km from the basin’s
northeastern high-relief margin, where measurements
of water depth were C4.0 m (Fig. 1D). Baia Vermelha exhibits a highly variable surface area
(B150 km2), resulting from an expansive, low-gradient plain on the northern lake margin (Fig. 1E).
Several intermittent channels (*91–92 m a.s.l.)
connect BV with the PR on the eastern side of the
basin. The bathymetry of BV is complicated by the
presence of a circular headland *3.5 km offshore
from the northwestern axial lake margin. West of the
headland, bathymetric contours are approximately
concentric and reach a maximum depth of *3.1 m
(Fig. 1E). Baia Vermelha is deepest (*3.5 m) east of
the headland, *2 km from its southern, high-relief
lake margin.
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Fig. 2 Concentration maps of mean particle size, biogenic
silica, total nitrogen and total organic carbon for LG, LM, and
BV. Top row = LG. Middle row = LM. Bottom row = BV.
The contour interval is the same for each of the lakes,
illustrating the elevated productivity and burial of OM in LM
versus the other lakes
C/N, d13COM, and d15NOM values (Fig. 3). Values of
C/N and d13COM typically plot within known fields
for lacustrine algae mixed with C3-pathway terrestrial
plant matter (Meyers and Ishiwatari 1993). Values of
d15NOM range from ?1.8 to ?3.3%, with a mean of
?2.5%. Hydrogen index values for LG sediments are
\200 mg HC/gm TOC and plot near the Type II–
Type III kerogen boundary (Fig. 3).
Lake floor sediments in LM exhibit BiSi values
between 0.0 and 12.9 wt%, with a mean of 4.3 wt%
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Fig. 3 Cross plots of key biogeochemical indicators in the
surface sediments of LG, LM, and BV. A = TN versus TOC.
Sediments in LM are particularly rich in carbon and nitrogen,
suggesting elevated rates of primary productivity. B = d13C
versus C/N. Note the elevated C/N values exhibited by BV
sediments, probably due to an increased role of vascular plant
material in the basin’s carbon cycle. Sediments from LG fall
within well-defined ranges for mixed algal and C3-terrestrial
vegetation. C = d15N versus d13C. Low d15N values in some
LM sediments likely results from the presence of nitrogenfixing cyanobacteria in the basin. D = HI versus OI. Rock–
Eval pyrolysis data support a mixed organic provenance
interpretation for lakes in the Pantanal
(Electronic Supplementary Material Table 3). Axial
concentrations of BiSi are high ([7.0 wt%) in LM,
especially \2.5 km from the western lake shore
(Fig. 2). Sediments deposited near the basin sill have
less BiSi (B2.0 wt%). Total nitrogen ranges from 0.0
to 1.0 wt%, with a mean of 0.5 wt%, whereas values
of TOC are particularly high, ranging from 0.0 to 8.5
wt%, with a mean of 4.9 wt%. Contours of TN and
TOC indicate elevated concentrations on the western
side of the basin axis, away from fluvial point sources
(Fig. 2). Total nitrogen and TOC demonstrate statistically significant correlations with water depth in
LM (r2 = 0.51 and 0.46, respectively). Sediment OM
in LM exhibits the broadest range of d13C and d15N
values, whereas the range of C/N values (10.0–13.6)
is comparable to the other lakes (Fig. 3). The mean
d13COM isotopic composition (-24.0%) is at least
2.5% more positive than the means of LG and BV. In
contrast, values of d15NOM are the smallest in the
study area, with a range of -0.1 to ?3.2% and a
mean of ?1.4% (Electronic Supplementary Material
Table 3). Hydrogen index values for LM surface
sediments range from 206 to 357 mg HC/gm TOC
and fall within the Type II kerogen field (Fig. 3).
Lake floor sediments in BV exhibit BiSi values
between 0.0 and 4.3 wt%, with a mean of 1.6 wt%
(Electronic Supplementary Material Table 3). The
highest concentrations of BiSi are located west of the
headland and near the southeastern lake margin; most
of the lake floor substrates between the axial margins
are \2.0 wt% BiSi (Fig. 2). Total nitrogen ranges
from 0.0 to 0.4 wt%, with a mean of 0.2 wt%,
whereas values of TOC range from 0.0 to 4.4 wt%,
with a mean of 2.0 wt%. The patterns of TN and TOC
contours are similar to BiSi, with elevated concentrations along the axial margins (Fig. 2). C/N values
on BV samples are slightly higher (mean = 12.5)
than those measured in the other lakes, whereas
d13COM sample means are comparable to LG (-26.5
and -27.0%, respectively). Sediment OM in BV
exhibits d15NOM values that range from ?0.3 to
?4.4%, with a mean of ?3.1%. Hydrogen index
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values for BV sediments range from 123 to 287 mg
HC/gm TOC and plot near the Type II–Type III
kerogen boundary (Fig. 3).
Sedimentation rates were developed on two cores
from LG using 210Pb (Fig. 4). The upper 20–30 cm of
both cores contain massive, dark-green, silty clay
with OM, diatoms and sponge spicules commonly
present. Linear sedimentation rates vary spatially
within the southern sub-basin. Recent sedimentation
has been relatively slow (0.11 cm year-1) at core site
GVA09-3A, which is situated near the northern end
of the southern sub-basin (Fig. 1). At the southern
core site (GVA09-2A) recent sedimentation has
progressed more rapidly, at a rate of 0.24 cm year-1.
A 137Cs-derived geochronology for GVA09-3A of
0.1 cm year-1 supports the sedimentation rate
obtained from the excess 210Pb distribution.
Sponge microfossils
Figure 5 and Electronic Supplementary Material
Table 4 illustrate the variety of sponge microfossils
in the modern sediments of LG, LM and BV.
Megascleres and gemmoscleres of two lentic species
are common to all three lakes: Radiospongilla
amazonensis Volkmer-Ribeiro and Maciel 1983 and
Trochospongilla variabilis Bonetto and Ezcurra de
Drago 1973. In BV, spicules of the lentic sponge
Corvoheteromeyenia sp. range from common to
abundant in lake floor sediments west of the headland, but are much less common proximal to
connection points with the PR. Modern sediments
in the southern sub-basin of LG contained spicules of
Metania spinata Carter 1881 and Heteromeyenia sp.
sponges; both are commonly associated with lakes
and wetlands in the cerrado biome (Volkmer-Ribeiro
1992).
Notably, all three lakes contain the robust megascleres and gemmules of Corvospongilla secktii
Bonetto and Ezcurra de Drago 1966, a sponge known
to colonize rocky substrates and channel-margin
vegetation in large neotropical rivers (Fig. 5; Batista
et al. 2003). These spicules are found in sediments
across LG and BV, but are more localized in LM.
Lagoa Mandioré also contains abundant spicules of
the lotic sponge Oncosclera navicella Carter 1881 in
sediments deposited near the basin sill; such spicules
were not detected in the center and northern axis of
the basin. In LG, spicules of lotic sponges are present
281
across the basin, and include gemmoscleres of
Uruguaya corallioides Bowerbank 1863.
Discussion
Any discussion of limnogeological processes in the
floodplains of the Pantanal must consider the downstream variability exhibited in the passage of the PR
flood pulse. A key characteristic distinguishing LG,
LM and BV from floodplain lakes in many other
tropical watersheds is the near anti-phasing of the
dominant rainy season with the arrival of riverine
flood waters (Veloso 1972; Heckman 1998). The 2- to
4-month time lag associated with the passage of the
PR flood pulse from the north to the central Pantanal
is important to lake hydrochemistry, morphometrics,
and sedimentation processes. The arrival of the PR
flood pulse following the austral summer causes lake
surface areas, fetch distances and bathymetric gradients to reach their maxima as wind speeds begin to
reach peak velocity (Electronic Supplementary Material Fig. 1). This combination has implications for
wave development, sediment re-suspension and the
temporal continuity of stratigraphic records. Because
of its tapered shape and short effective fetch, the
deepest regions of LG likely escape the influence of
waves (critical depth = 4.1 m), whereas the potential
for wave reworking and sediment re-suspension is
much higher in LM and BV due to their morphometries. This difference provides a plausible explanation for the ‘‘well-behaved’’ decay of excess 210Pb
in the uppermost sediments in LG (Fig. 4). Shortterm stratigraphic records from the deepest parts of
LG are continuous, whereas those from LM and BV
appear to be more punctuated. Unsupported 210Pb in
LM is confined to the upper 2–3 cm of sediment
cores, and is interpreted to result from recent wavedriven re-suspension of sediments at the core site.
The impact of waves on LM is further illustrated by
shoreline-parallel sand bars and cuspate sandy
beaches. Such features are well known from lakes
with high-energy coastlines (Adams and Wesnousky
1998). In BV, erratic downcore concentrations of
excess 210Pb suggest that bioturbation may impact the
continuity of the stratigraphy of this basin (Sharma
et al. 1987). Feral cows and gregarious water birds in
the central Pantanal make the potential for shallowwater bioturbation high (Por 1995). Highly variable
123
282
J Paleolimnol (2011) 46:273–289
Fig. 4 210Pb profiles for sediment cores from LG; location of
cores shown in Fig. 1. Continuity of sedimentation among the
study lakes is highly variable, probably due to differences in
morphometries and bathymetry. Fairly linear decline of log
excess 210Pb with depth in LG due to the lake’s water depth,
which at many locales exceeds the critical wave depth. Dpm/
g = disintegrations per minute per gram. Dark symbols =
mixed layer samples, grey symbols = samples used in age
model
sedimentation rates could produce a similar downcore
210
Pb decay pattern, but massive lithologic units
bounded by irregular bedding planes in the BV
sediment core suggest this alternative is less likely.
123
Another key difference between the Pantanal lakes
and other floodplain lakes is the mechanism of
riverine inundation. The water cycles of many
tropical floodplain lakes rely on groundwater seepage
or overland flow when bankfull conditions are
exceeded (Cohen 2003). In contrast, LG, LM and
BV are silled basins linked to the PR by channels.
Tributaries connecting the lakes to the PR not only
influence water cycling, but also impact lake sedimentology. Channels impart a first-order control on
flow velocity and the routing of bed-load into the lake
basins, whereas unconfined overland flows are more
diffuse, allowing vegetated levees and floodplain
soils to act as sediment traps. Terrigenous particlesize contours show the impact of fluvial tractionflows on the lakes (Fig. 2). Fan-shaped sand bodies
occupy broad areas of the lake floors and are key
components of the modern facies architecture that are
genetically linked to the passage of the flood pulse.
The orientation of fan apices confirms that flows
originating at basin sills are the source of these
deposits. Another hallmark of ‘‘fill-phase’’ sedimentology is the presence of lotic sponge microfossils,
which reflect at least seasonal connectivity between
the lakes and the PR. The ecological characteristics of
sponge remains are well known, and the spicules of
lotic species are typically well preserved, albeit with
some taphonomic overprint from transport (Batista
et al. 2003; Volkmer-Ribeiro and Pauls 2000). Prior
research in Brazil has demonstrated the utility of
spicule analysis to discriminate between fluvial and
lacustrine environments in sediment cores (Parolin
et al. 2007). Results from the present study show that
down-core variability in lotic versus lentic assemblages could provide an important ecological perspective on fluvial-lacustrine connectivity for the
floodplain lakes of the Pantanal.
In our study lakes, mean particle sizes are
generally in the silt range. Coarser (sandy) sediments
are most prominent near sill points, although this
J Paleolimnol (2011) 46:273–289
Fig. 5 Common fluvial and lacustrine sponge spicules encountered in lake-bottom sediments from the study lakes. A = gemmosclere of the lotic sponge Corvospongilla secktii. B =
gemmosclere of the lotic sponge Oncosclera navicella. C = gemmosclere of the lentic sponge Radiospongilla amazonensis.
283
D = gemmosclere of the lentic sponge Trochospongilla variabilis. E = gemmosclere of the lotic sponge Uruguaya corallioides.
F = megasclere of the lentic sponge Heteromeyenia sp.
G = megasclere of the lentic sponge Corvoheteromeyenia sp.
I = megasclere of the lentic sponge Metania spinata
123
284
relation is complicated in BV given its low-relief
eastern margin, which likely receives inflow from the
PR at several points. Particle sizes tend to be finest in
deep-water regions, which in most cases are located
proximal to margins with coincident topography;
suspension settling and organic sedimentation are
common in these locales. Although sub-surface
datasets from the lakes are unavailable, the correlation of bathymetric lows and high-relief rocky
margins suggests the potential for neotectonic controls on accommodation space in the basins (Fig. 1).
In the Pantanal, structural influences on fluvial
channel patterns are not uncommon and shallow
earthquakes have been recorded in the region (Assine
and Soares 2004). Por (1995) suggested that karst
plays an intimate role in large lake formation in the
Pantanal, but our data suggest that this is not likely
for LG, LM and BV. Hydrochemical datasets show
that the lakes are extremely dilute, whereas karst
basin waters are typically rich in divalent metals due
to dissolution of carbonate aquifers (Electronic
Supplementary Material Table 2). During sampling,
the lake waters broadly reflected the chemical
composition of the PR, especially for conservative
cations; these waters are undersaturated with respect
to calcite (Hamilton et al. 1997).
We interpret a three-phase seasonal evolution that
links lacustrine hydrochemistry, morphometrics and
sedimentology to stage of the PR, which is strongly
modulated by regional climate (Electronic Supplementary Material Fig. 3). Seasonal evolution of the
large lakes of the Pantanal shares a number of
similarities with lakes on the floodplain of the
Orinoco River in Venezuela described by Hamilton
and Lewis (1987). Channelized linkages to the PR
may serve as conduits for reversing flows following
the passage of the flood pulse, during a transient
‘‘draining-phase’’ leading to full isolation of the lakes
from the river (Electronic Supplementary Material
Fig. 3). In the central Pantanal, the stage height of the
PR drops by C5 m in the austral summer, when the
flood pulse is retained in the north and evaporation
increases due to elevated air temperatures. Theoretical estimates of lake level decline due to evaporation
alone indicate lake surfaces drop by at least 0.6 m
annually. At peak inundation, lake-surface altitudes
for LG, LM and BV are typically 5, 4, and 6 m below
their sill heights, respectively. As a result, short-lived
reversed flows are probable for LG and LM, and
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J Paleolimnol (2011) 46:273–289
possible, but likely rare, for BV. Complete isolation
of the lakes generally occurs in the austral summer,
suggesting direct rainfall and groundwater inputs are
less important to morphometrics and bathymetry than
the PR flood pulse.
Both fluvial and lacustrine processes control
organic facies development in the large lakes of the
Pantanal. River-borne solutes probably provide a key
source of nutrients that help control algal productivity
in LG, LM and BV. Junk et al. (1989) were among
the first to recognize the importance of flood pulse
dynamics for nutrient delivery and productivity in the
tropics, whereas Hamilton et al. (1997) noted that the
floodplains of the central Pantanal are sinks for flood
pulse-derived OM and sites of inorganic nutrient
transformation. Concentrations of N, P and suspended solids, however, are lower in the PR than in
other rivers draining tropical savannas (Hamilton
et al. 1997). As a consequence, local allochthonous
sources of nutrients may likewise be important.
Macrophyte decomposition and internal recycling
are two possible local sources of phytoplanktonlimiting nutrients. Floating macrophytes and marsh
vegetation are commonly encountered along the
margins of each of the lakes, and dry-season decomposition of such vegetation is a known source of
dissolved nutrients in other floodplain lakes (Furch
et al. 1983). Likewise, mixing-driven re-suspension
of lake bottom sediments can lead to the release of
nutrients, but this process also prolongs the exposure
of labile organic compounds to degradation by
aerobic respiration (Forsberg et al. 1988; Henrichs
1992). Ultimately, OM-rich facies development
across broad regions of the lakes is mediated by
dilution during ‘‘fill-phase’’ sedimentation.
Biogeochemical signals in LM samples are complex and appear to reflect elevated productivity and
subsequent degradation (Fig. 2). Organic sediments
from LM are relatively rich in 13C (Fig. 3). The
factors that can influence d13COM values include: (1)
the isotopic composition of the carbon source (commonly lake water DIC); (2) phytoplankton assemblage and metabolic rates; (3) the proportion of C3 and
C4 terrestrial vegetation within particulate organic
matter; and (4) diagenesis (Meyers and Teranes 2001;
Talbot and Johannessen 1992). At present, d13CDIC
measurements on lake or river water samples are
unavailable, but we assume that the concentration of
aqueous CO2 is relatively low due to LM’s pH (8.3).
J Paleolimnol (2011) 46:273–289
Therefore, utilization of HCO3- during photosynthesis may partially contribute to the enriched carbon
isotopic signature observed in these samples (Fig. 3).
Hamilton et al. (1997) noted that C/N values for
particulate organic matter (POM) in the PR averages
8.5, but that algae comprised only a small portion of
this OM. Wantzen et al. (2002) reported a range of
-26.0 to -32.0% for d13C values in POM in the
northern Pantanal. These values are consistent with
geochemical characteristics of both C3 terrestrial
plants and algae. Smear slides show that LM
sediments contain abundant green algae and diatoms,
with cyanobacteria, including Anabaena sp., common
in some samples (Electronic Supplementary Material
Fig. 2). Algae blooms were observed during our
sampling and the relatively high d13C values can at
least be partially accounted for by the preferential
uptake of 12C during photosynthesis, thus depleting
the residual DIC reservoir in the lake (McKenzie
1985; Amorim et al. 2009). Given its long fetch
(*22 km), wind-driven internal nutrient fertilization
provides a compelling explanation for algal blooms
and elevated carbon burial in LM. Intriguingly,
samples with anomalously high d13C values generally
exhibit nitrogen isotope ratios below 2.0% (Fig. 3).
The presence of nitrogen-fixing cyanobacteria in these
samples provides one viable explanation for these
d15N values, as well as the high TN concentrations
(Talbot 2001). However, HI values from LM are
below 400 mg HC/gm TOC, suggesting that cyanobacteria do not dominate the phytoplankton assemblage and local allochthonous sources may also
contribute to the lake’s carbon cycle (Talbot and
Livingstone 1989). Importantly, oxygen index values
exceeding 200 mg CO2/gm TOC indicates that diagenesis also affects the geochemistry of OM in LM.
Re-suspension and oxidation of buried sediments can
alter primary geochemical signals, due to selective
loss of N and 12C (in the latter, due to oxidative
fractionation that may increase d13COM values by
1–2%). Therefore, elevated C/N and d13COM may in
part reflect the influence of oxidation in some samples.
Biogeochemical data from LG and BV lack the
variability of samples from LM and suggest lower
primary productivity. Sediment OM samples from LG
and BV have low d13C values and C/N values \20,
commonly thought to reflect admixtures of lacustrine
algae and vascular plants (Meyers and Ishiwatari
1993). Values of lake-water pH suggest that dissolved
285
CO2 in isotopic equilibrium with the atmosphere is
likely the DIC source for primary producers in these
lakes. Hydrogen index values below 300 mg HC/gm
TOC for both LG and BV support the interpretation of
a mixed organic provenance. Examination of smear
slides confirms the presence of algae and terrestrial
plant fragments in both lakes (Electronic Supplementary Material Fig. 2). In general, the nitrogen isotope
composition of OM from LG and BV is consistent
with d15N values associated with lake sediments
composed of both algae, which commonly preserve
the isotopic signature of lake-water dissolved inorganic nitrogen, and terrestrial vegetation, which
utilize atmospheric N2. The data are also consistent
with common aquatic macrophytes and flood-pulsederived POM in the Pantanal. Several BV samples,
collected west of the headland, exhibit high d13C
values and low d15N values (\2.6%); lake-margin
marshes, dominated by C4-pathway Paspalum repens
likely contribute to the isotopic composition of these
samples (Fellerhoff et al. 2003). Rock–Eval data
suggest that post-depositional alteration of OM is less
pronounced in LG and BV when compared with LM,
likely the result of differences in wave development
and sediment re-suspension.
Figure 6 presents a conceptual model of sedimentation derived from the observed modern seasonal
sedimentation cycle and its linkages to the PR flood
pulse. Data described in this study provide constraints
on the processes that influence modern lithofacies
patterns and geochemical baselines. With caution,
these inferences can be used to predict facies
migrations during intervals of major environmental
change, such as those that might be preserved in
sediment core records. Evidence of meaningful
alteration of climate is already well established by
relict landforms (dunes, lunettes, and deflation pans)
in the southern Pantanal (Soares et al. 2003). Thus,
over short intervals of time, climate change in the PR
headwaters is clearly an important mechanism that
could lead to significant change in sedimentation in
LG, LM and BV. Climatic conditions that promote a
stronger flood pulse and deeper lakes, such as
sustained southerly advance of the ITCZ, are likely
to: (1) create additional fluvial entry points into the
lakes, leading to ephemeral marginal fans; (2) backflood existing incipient river channels, creating
highstand deltas; (3) increase primary productivity
and algal OM deposition due to enhanced riverine
123
286
J Paleolimnol (2011) 46:273–289
Fig. 6 Conceptual model of sedimentation in the floodplain
lakes of Pantanal, based on modern inferences. Solid line
around lake perimeter in B indicates modern shoreline, and
broken lines in A and C denote position of modern shoreline
relative to hypothetical lake highstands and lowstands. See text
for details
nutrient supply; (4) enhance the accumulation of
sponge spicules from lotic species assemblages; and
(5) develop fine-grained organic facies where suspension fall-out processes dominate, possibly with
higher temporal continuity due to increased water
depths. In contrast, sustained lake level lowstands
associated with reduced effective precipitation in the
PR headwaters will serve to magnify ‘‘isolationphase’’ processes and sedimentation, including: (1)
incision of incipient river channels, with the potential
for lowstand fan deposition; (2) sporadic deposition
of lotic sponges; (3) possible precipitation of reduced
metals and carbonate as isolated lake waters concentrate and mix; (4) reworking of sub-aerially exposed
lake-bottom deposits, through deflation or bioturbation; (5) greater deposition of terrestrial OM from the
local watershed; and (6) oxidation of labile biogenic
sediments and diagenetic evolution of elemental and
stable isotopic values on OM (Fig. 6). A space-fortime substitution with large lakes in the southern
Pantanal, e.g. Lagoa Cáceres (Fig. 1), provides
insights into chemical sedimentation during lowstands. This region experiences lower yearly precipitation and delayed passage of the flood pulse; minor
calcite precipitation occurs in these lakes today
(Electronic Supplementary Material Table 5).
Clearly, changes in sediment accumulation rates can
be expected as major hydrologic thresholds are
crossed, especially during lowstands when sedimentation is more discontinuous.
The processes described herein are likely common
to many floodplain lake systems, often resulting in
low-to-intermediate-resolution records with highly
variable sedimentation rates (Cohen 2003). Importantly, neotectonic alterations of drainage patterns are
an alternative mechanism that could substantially
alter the PR and its connection to floodplain lakes in
the Pantanal. For example, faulting of the shallow
crust has been implicated in the capture and redirection of large rivers in tropical Africa, which in some
cases have influenced sedimentation processes in
wetlands and lakes (Gumbricht et al. 2001; McGlue
et al. 2006). Similar tectonic processes could affect
the position of the PR, cutting the lakes off from the
flood pulse and leading to ‘‘isolation-phase’’ sedimentation. Likewise, crevasse splay development and
channel migrations have been documented in the
central Pantanal over the past several decades (Assine
2005). Avulsion of the PR could spur meaningful
changes in the magnitude of the flood pulse on LG,
LM and BV without coeval climate change. Independent constraints on fluvial geomorphic evolution
are therefore necessary for interpreting paleoenvironments in the Pantanal and similar wetlands.
123
Conclusions
Owing to their role in biogeochemical cycles, biodiversity and as a water resource, understanding the
J Paleolimnol (2011) 46:273–289
response of large tropical wetlands to global change
is critically important. A potentially rich paleolimnological archive of Quaternary environmental
dynamics for tropical wetlands exists in the sediments
of floodplain lakes. Interpreting these records effectively, however, requires a highly nuanced understanding of how these lakes act as depositional
basins. The results of this actualistic assessment yield
new insights into these limnogeological processes for
three large floodplain lakes in the Brazilian Pantanal.
1.
2.
3.
Situated along the western margin of the PR and
strongly influenced by its flood pulse, LG, LM
and BV are freshwater, well-oxygenated, weakly
basic, dilute limnological systems with elongate
shorelines and shallow maximum water depths
(\5 m). Correlation of bathymetric maxima and
coincident margins suggests a neotectonic control on lake formation, likely modulated by
channel migrations of the PR.
The flood pulse of the PR impacts the limnogeology of each of the study lakes through delivery
of terrigenous grains, lotic sponge spicules,
POM, nutrients and through modulation of lake
shape, depth, and water chemistry. Sediment
biogeochemistry (BiSi, TN and TOC) suggests
that production and burial of biomass is highest
in LM and somewhat lower in LG and BV.
Stable isotopes of carbon and nitrogen and HI
values indicate a mixed (lacustrine algae, macrophytes and vascular plants) organic matter
provenance for the lakes. Post-depositional resuspension of lake-bottom sediments by waves
and bioturbation influence geochemical signals
and depositional continuity in these shallow
basins. Sites of uninterrupted sedimentation were
only encountered in the deepest regions of LG,
where the decay of short-lived radioisotopes
indicates that sedimentation rates ranged
between 0.11 and 0.24 cm year-1.
Sensitivity of the PR flood pulse to climate
change, neotectonics and fluvial autocyclicity has
important implications for floodplain limnogeology. Our conceptual depositional model suggests
that intensification of the PR flood pulse is likely
to be represented by higher lake levels and a
concomitant decrease in grain size, an increase in
the burial of aquatic OM due to elevated
productivity, depositional continuity, and lotic
287
sponge assemblages. Weakening of the flood
pulse promotes chemical and sandy lowstand fan
sedimentation, terrestrial OM deposition, oxidation and bioturbation as the lakes become
isolated and contract on the floodplain. Actualistic datasets and space-for-time considerations
developed herein provide a predictive framework
for facies migrations that can be captured and
dated in sediment cores from these or similar
lakes with linkages to large tropical rivers with
sustained seasonal flooding.
Acknowledgments The title for this contribution was
adapted from: The Pantanal—Brazil’s Forgotten Wilderness
by Vic Banks (1991). The research presented in this paper was
supported by the American Chemical Society (PRF program
grant 45910-AC8), the São Paulo Research Foundation
(FAPESP grant 2007/55987-3) and the UA-Exxon Mobil
COSA project. Generous grants to MM from Laccore, the
Chevron Corporation, Kartchner Caverns, and PAGES assisted
the completion of this project. Research in Brazil would not
have been possible without logistical and scientific support
from ECOA-Brazil, EMBRAPA-Brazil, UFMS—Campus do
Pantanal, the Fazenda Santa Teresa and the citizens of Amolar
(MS—Brazil). We are extremely grateful to K. Wendt, F. dos
Santos Gradella, S. Kuerten, B. Lima de Paula, D. Calheiros,
R. Lins, A. Lins, and T. Matsushima for their assistance.
C. Gans and E. Guerra de Lima provided vital support at UA
during our 2009 field season. L. Helfrich, C. Landowski, X.
Zhang, C. Eastoe, J. Ash and the staff of the Limnological
Research Center at the University of Minnesota provided
support in the laboratory. Critical reviews by S. Harris, C.
Turner, S. Ivory, M. Blome, M. Brenner and two anonymous
reviewers substantially improved the quality of the text.
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J Paleolimnol
DOI 10.1007/s10933-011-9545-6
ERRATUM
Erratum to: Limnogeology in Brazil’s ‘‘forgotten
wilderness’’: a synthesis from the large floodplain
lakes of the Pantanal
Michael M. McGlue • Aguinaldo Silva • Fabrı́cio A. Corradini • Hiran Zani
Mark A. Trees • Geoffrey S. Ellis • Mauro Parolin • Peter W. Swarzenski •
Andrew S. Cohen • Mario L. Assine
•
! Springer Science+Business Media B.V. 2011
Erratum to: J Paleolimnol (2011) 46:273–289
DOI 10.1007/s10933-011-9538-5
The caption for Fig. 5 is incorrect. It should read:
Fig. 5 Common fluvial and lacustrine sponge spicules encountered in lake-bottom sediments from the
study lakes. A = gemmosclere of the lotic sponge
Corvospongilla secktii. B = gemmosclere of the lotic
sponge Oncosclera navicella. C = gemmosclere of
the lentic sponge Radiospongilla amazonensis.
The online version of the original article can be found under
doi:10.1007/s10933-011-9538-5.
M. M. McGlue (&) ! M. A. Trees ! A. S. Cohen
Department of Geosciences, The University of Arizona,
1040 East 4th Street, Tucson, AZ 85721, USA
e-mail: mmmcglue@email.arizona.edu
G. S. Ellis
Energy Resources Program, U.S. Geological Survey,
Denver, CO, USA
e-mail: gsellis@usgs.gov
M. A. Trees
e-mail: treesma@email.arizona.edu
M. Parolin
Faculdade Estadual de Ciências e Letras de Campo
Mourão, Av. Comendador Norberto Marcondes, 733,
Campo Mourão, PR 87303-100, Brazil
e-mail: mauroparolin@gmail.com
A. S. Cohen
e-mail: cohen@email.arizona.edu
A. Silva
Departamento de Ciências do Ambiente, Universidade
Federal de Mato Grosso do Sul—UFMS-CPAN, Av. Rio
Branco, 1270, Corumbá, MS 79304-902, Brazil
e-mail: aguinald_silva@yahoo.com.br
F. A. Corradini
Faculdade de Geografia, Universidade Federal do ParáUFPA, Folha 31, Quadra 7, Lote Especial S/N, Marabá,
PA 68501-970, Brazil
e-mail: f_coradini@yahoo.com.br
P. W. Swarzenski
U.S. Geological Survey, Santa Cruz, CA, USA
e-mail: pswarzen@usgs.gov
M. L. Assine
Departamento de Geologia Aplicada—IGCE,
Universidade Estadual Paulista—UNESP/Campus Rio
Claro, Av. 24-A, 1515, Rio Claro, SP 13506-900, Brazil
e-mail: assine@rc.unesp.br
H. Zani
Divisão de Sensoriamento Remoto, Instituto Nacional de
Pesquisas Espaciais—INPE, Av. dos Astronautas, 1758,
Saõ José dos Campos, SP 12201-970, Brazil
e-mail: hzani@dsr.inpe.br
123
J Paleolimnol
D = gemmosclere of the lentic sponge Trochospongilla variabilis. E = gemmosclere of the lotic sponge
Uruguaya corallioides. F = gemmosclere of the
123
lentic sponge Heteromeyenia sp. G = gemmosclere
of the lentic sponge Corvoheteromeyenia sp.
H = megasclere of the lentic sponge Metania spinata