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Y. Govender, E. Cuevas, L. D. S. Sternberg, and M. R. Jury

the next sampling period. A subsample of the rainwater samples was tested for salinity using a Brix refractometer at the time of collection. Vacutainers were stored in a refrigerator (4°C) in the laboratory until analysis at the Laboratory of Stable Isotope Ecology in Tropical Ecosystems (University of Miami). A total of 49 rainwater samples were analyzed in triplicate for δ 18 O and δD by mass spectrometry using methods described by Vendramini and Sternberg ( Vendramini and Sternberg 2007

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A. P. Ballantyne, P. A. Baker, J. Q. Chambers, R. Villalba, and J. Argollo

from the Volcan Granada subpopulation. From this subpopulation, we selected one long-lived individual for our isotopic analysis that was highly correlated with the regional climate reconstruction ( R 2 = 0.90), suggesting that this individual was representative of the larger population. Unfortunately, because of the thin annual growth bands in Polylepis , there was only enough material for δ 18 O cx analysis and not δ 13 C cx . The single Tachigali sample from Manaus was thinly sliced

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Vincent Bustillo, Reynaldo Luiz Victoria, Jose Mauro Sousa de Moura, Daniel de Castro Victoria, Andre Marcondes Andrade Toledo, and Erich Colicchio

to inputs and outputs. By comparing the outputs of many different models designed for different purposes, the nature and the magnitude of processes linking water and biogeochemical budgets of the Amazonian floodplains were clarified. Each one provides a specific insight on the soil–river system dynamics by coupling hydrological, sedimentary, and biogeochemical budgets. The comparison of the model outputs, and the analysis of their reciprocal consistency, enabled us to decipher much more assuredly

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Jason A. Hubbart and Chris Zell

aquifers in dissected till plains (north-central Missouri) . Ground Water , 22 , 683 – 689 . Sidle , W. , and P. Lee , 1999 : Urban stormwater tracing with the naturally occurring deuterium isotope . Water Environ. Res. , 71 , 1251 – 1256 . Smith , R. , and R. Hebbert , 1979 : A Monte Carlo analysis of the hydrologic effects of spatial variability of infiltration . Water Resour. Res. , 15 , 419 – 429 . Sophocleus , M. , 2002 : Interactions between groundwater and surface water

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Vincent Bustillo, Reynaldo Luiz Victoria, Jose Mauro Sousa de Moura, Daniel de Castro Victoria, Andre Marcondes Andrade Toledo, and Erich Collicchio

contributive runoff in a continuous way and at a sufficient number of locations is practically impossible ( Tardy et al. 2004 ; Bustillo 2005 ). Hydrograph separation methods can be divided in two main categories: tracer-based and nontracer-based separation methods. Nontracer-based separation methods are based on the analysis of hydrographs, including a large variety of procedures, including graphical analysis of recession curves, low-pass filtering, unit hydrograph modeling with extrapolation to rising

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Tomas F. Domingues, Joseph A. Berry, Luiz A. Martinelli, Jean P. H. B. Ometto, and James R. Ehleringer

Dried subsamples (1–2 mg) of each leaf collected for LMA determinations were used for δ 13 C and N area determinations by continuous-flow isotope ratio mass spectrometry (IRMS Delta Plus Finnigan Mat) coupled with an elemental analyzer (Carlo Erba). Analyses were performed at the Laboratório de Ecológia Isotópica, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil. Carbon isotope ratios are expressed in delta notation relative to PeeDee Belemnite (PDB) standard

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E. T. A. Mitchard, S. S. Saatchi, F. F. Gerard, S. L. Lewis, and P. Meir

and soil carbon isotopes ( 13 C/ 12 C, 14 C) along two transects in eastern Cameroon to show both significant expansion of the forest and that increased woody cover of the savanna has occurred over the past century. Nangendo et al. ( Nangendo et al. 2005 ) used a combination of field studies and vegetation index–based satellite change detection to find a 14% increase in woody vegetation over a 14-yr period in the woodlands of the Budongo Forest Reserve, Uganda. However, all the African studies

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Kevin G. Harrison, Richard J. Norby, Wilfred M. Post, and Emily L. Chapp

of the “missing sink.” Using measurements of stable carbon isotopes in the atmosphere, Ciais et al. ( Ciais et al.1995 ) have shown that the terrestrial biosphere removed about half of fossil fuel emissions in 1992 and 1993, or about 3.5 Gt C yr −1 from the atmosphere. Using atmospheric oxygen measurements, Keeling et al. ( Keeling et al. 1996 ) have shown that the terrestrial biosphere sequestered about 2.0 ± 0.9 Gt C yr −1 (about one-third of fossil fuel input) from 1991 to 1994. Because

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Michael Garstang, David R. Fitzjarrald, Kurt Fristrup, and Conrad Brain

) used isotopes of carbon, nitrogen, and oxygen in ivory from tusks of known place and time of origin to determine the possible role of climate, vegetation, and water quality in the elephant’s diet in the Etosha National Park (ENP). Oxygen isotopes indicating differences in water quality in the dry season reflect the spatial distributions of the elephants. The area served by the two primary water holes, Mushara and Kameeldoring, lies within one of four regions in the ENP identified by the isotopic

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Marcello Gugliotta, Jonathan G. Fairman Jr., David M. Schultz, and Stephen S. Flint

and Dashtgard 2012 ; Johnson and Dashtgard 2014 ) and may be recognized in the geologic record using techniques such as isotope geochemistry ( Allen et al. 2007 ), fossilized trees ( Morgans et al. 1999 ), pollen studies ( Dark and Allen 2005 ), trace fossils ( Gingras et al. 2002 ), and sedimentology ( Gugliotta et al. 2015 , 2016 ). Another technique that can be applied to determine seasonal fluctuations in river discharge is paleoclimate modeling, whereby a climate model is set up with

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