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  • Fluorescence excitation-emission matrix (EEM) spectroscopy, humification index (HIX) and specific UV absorbance (SUVA) at 254 nm were to characterize depth and seasonal variations of Dissolved Organic Matter (DOM) composition within sediments of a semi-arid floodplain at Rifle, Colorado, USA. It is expected that these relatively simple spectroscopic measurements (e.g., EEM spectroscopy, HIX and SUVA) applied to depth- and temporally-distributed pore-water samples can provide useful insights into transport and humification of DOM in other subsurface environments as well.
    Data Types:
    • Dataset
  • Raw sapflow data from K34 tower site on a plateau near Manaus, Brazil. These are mostly raw data from the data loggers, except in the case of the ICT sensors where the datalogger output was translated using ICT software. One heat ratio sap flow sensor (SFM1, ICT international) was installed per tree. Tree biophysical characteristics for each tree were used with Sap Flow Tool version 1.4.1 (ICT International/Phyto-IT) to calculate sap velocities from raw data downloaded from the SFM1 sap flow sensors in the field. Attached data files include data, sensor manuals, and detailed methods. Related metadata is contained in referenced dataset. This dataset replaces the sapflow data of two retired packages, http://dx.doi.org/10.15486/ngt/1507764 and http://dx.doi.org/10.15486/ngt/1507767
    Data Types:
    • Dataset
  • In this study, the oxidation of 2-methoxyhydroquinone (MH2Q) by ferric iron (Fe(III)) under dark conditions in the absence and presence of oxygen was investigated within a pH range of 4 – 6. While Fe(III) was capable of stoichiometrically oxidizing MH2Q under anaerobic conditions, catalytic oxidation of MH2Q was observed in the presence of O2 due to further cycling between oxygen, semiquinone radicals, and iron species. A detailed kinetic model was developed to describe the predominant mechanisms, which indicated that both the undissociated and mono-dissociated anions of MH2Q were kinetically active species towards Fe(III) reduction, with the mono-dissociated anion being the key species accounting for the pH dependence of the oxidation. The generated radical intermediates, namely semiquinone and superoxide, are of great importance in reaction chain propagation. The kinetic model may provide critical insight into the underlying mechanisms of the thermodynamic and kinetic characteristics of metal-organic interactions and assist in understanding and predicting the factors controlling iron and organic matter transformation and bioavailability in aquatic systems.
    Data Types:
    • Dataset
  • The data included in this data package are a demonstration of an inverse relationship in the early successional species Vismia guianensis in the central Amazon between stomatal conductance (gs) and leaf temperature, while net photosynthesis (Pn) showed an optimum value of 32.6 ± 0.4°C. In contrast to Pn, photosynthetic electron transport rates (ETR) and the QA oxidation state (qL) increased linearly with leaf temperature. Leaf isoprene emissions, a primary product of photosynthesis and strongly linked to plant high temperature stress tolerance, showed strong linear correlations with ETR (ρ = 0.98) and qL (ρ = 0.99). Furthermore, inhibition of isoprenoid biosynthesis repressed Pn at high temperatures through a mechanism that was independent of stomatal closure. Data will be used in the publication, "Stimulation of isoprene emissions and electron transport rates as a key mechanism of thermal tolerance in the tropical species Vismia guianensis." See the below Dataset References field for the full citation.
    Data Types:
    • Dataset
  • This dataset provides the tabular summary of analysis of 14 reaches of 13 Arctic rivers for river bank erosion and accretion rates, as well as, river channel properties such as channel width, bank curvature, and the aspect/orientation of the river banks. These rivers include the: Colville River, Alaska; Indigirka River, Russia; Kolyma River, Russia; Koyukuk River, Alaska; Lena River, Alaska; Noatak River, Alaska; Ob River, Russia; Pechora River, Russia; Selawik River, Alaska; Taz River, Russia; Yana River, Russia; Yenisei River, Russia;, and the Yukon River, Alaska. The dataset was generated from a total of 114 images including: Landsat, higher resolution satellite imagery, and aerial photography over time periods ranging from the 1970s and 2016. A full list of the image dates, row and path (for Landsat), and pixel resolutions is provided in the dataset. The masks were analyzed using the Spatially Continuous Riverbank Erosion and Accretion Measurements (SCREAM) software detailed in Rowland et al. 2016. The masks used in this analysis can be found an accompanying dataset (DOI: ess-dive-cfcff853f5ad92c-20191022T180804907). In files with "summary" in the name, the data is provided at a pixel level, where each mapped bank pixel has an associated erosion or accretion value, a channel width, a curvature value, and an aspect each river and time period will have an individual file. Files with "Segments" in name provide data that is averaged along segments of the rivers. These data are consolidated into a single file each for the erosion and accretion measurements. These segments are approximately 10 channel widths in length. In addition to erosion and accretion rates, the segment-based results include area measurements of erosion and accretion, islands, and channels. The number of islands is also included.Rowland JC, et al. (2016) A morphology independent methodology for quantifying planview river change and characteristics from remotely sensed imagery. Remote Sens Environ 184. doi:10.1016/j.rse.2016.07.005.
    Data Types:
    • Dataset
  • Data tables used in Arora et al. 2016b Influence of hydrological, biogeochemical and temperature transients on subsurface carbon fluxes in a flood plain environment. Biogeochemistry, 127(2-3), 367-396. Files include reactive transport model parameters describing soil physical and thermal parameters, geochemical reaction network and rate laws, as well as initial and boundary conditions. The last table documents modeling results with respect to annual carbon fluxes from the site to the river.
    Data Types:
    • Dataset
  • This data package contains a set of Functionally Assembled Terrestrial Ecosystem Simulator (FATES) history files and parameter values for the set of model simulations used in Koven et al. Manuscript "Benchmarking and Parameter Sensitivity of Physiological and Vegetation Dynamics using the Functionally Assembled Terrestrial Ecosystem Simulator (FATES) at Barro Colorado Island, Panama." It includes several ensembles of FATES runs, where each ensemble is comprised of a set of 576 runs that have different values of PFT traits. The ensembles include 1 PFT, 2 PFT, 3 PFT, and 10 PFT simulations. Different ensembles also have different values of disturbance and height sorting parameters, and structural differences including running FATES within different LSMs.
    Data Types:
    • Dataset
  • Raw and processed data from K34 tower site on a plateau near Manaus, Brazil including automated and manually collected time series data on leaf surface temperature (thermocouples, IR radiometer, thermocamera), leaf gas exchange fluxes of CO2, isoprene emissions, and H2O, sap flow, leaf water potential, soil moisture, and ambient concentrations of volatile organic compounds. IR radiometer data from the B34 tower in the nearby valley is also included.
    Data Types:
    • Dataset
  • This package is part of the Watershed Function SFA Data Collection and contains remote sensing data and geophysical measurements acquired at the Pumphouse hillslope-floodplain site, in the East River, Colorado. The remote sensing dataset includes: a) a WorldView-2 (WV-2) pan-sharpened multi-spectral remote sensing image, and b) LiDAR derived products. The WV-2 image was acquired on September 24th, 2015, and it is composed of eight spectral bands (coastal, blue, green, yellow, red, red edge, NIR1, and NIR2) with a spatial resolution of 0.5 m, covering an area of 750x750 m. The LiDAR products are a digital surface model (DSM), representing the top-of-canopy elevation, and a digital terrain model (DTM), representing the bare-ground elevation, at the spatial resolution of 0.5 m. Such data are extracted from the LiDAR point-cloud dataset acquired over the entire watershed on August 2015 (http://dx.doi.org/10.21952/WTR/1412542). The geophysical dataset is composed of the electrical resistivity tomography (ERT) data acquired along a 158.75 m long transect, spanning the hillslope topographical gradient with 1.25 m electrode spacing. The dataset also includes soil water content measured with a TDR system. The package provides also polygons of different vegetation communities, which were used as reference data for mapping plant community distributions. The spatial polygons are based on plant locations acquired during the field campaign of June-July 2017 using an RTK DGPS system. The reference dataset is composed by 11 vegetation classes, namely, deciduous forest, evergreen forest, riparian shrubland, sagebrush, shrubland, potentilla, frasera, lupine meadow, veratrum, bunchgrass meadow, and forb, as well as four non-vegetation classes, such as water-river, water-lake, man-made, bare area, and shadow. The vegetation classes are determined based on distinct spectral and/or structural signatures of dominant species. The package includes products derived by these datasets, such as: a) a plant height map, computed by subtracting the DTM from the DSM, and b) a plant community distribution map, obtained by using a data-fusion machine-learning-based framework that exploit the WV-2 image and plant height information.
    Data Types:
    • Dataset
  • This is the first dataset submission of ongoing measurements of sap flow, soil water content, and leaf surface temperature at San Lorenzo, Panama starting in 2015. The files include raw data output from data loggers, as well as files compiling some of the raw data together into single files.
    Data Types:
    • Dataset
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