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  • The synthesized deoxyribonucleic acid (DNA) solution and the DNA-functionalized polyacrylamide hydrogel for the detection of aqueous mercury(II) were tested with batch experiments using simple HDPE vials and centrifuge tubes under various pH, temperature and ionic strength conditions and in the presence of inorganic ligands and Suwannee River Fulvic Acid as a representative organic ligand. This purpose of this study is to evaluate the performance of the two types of aqueous mercury(II) biosensors under variable environmental conditions and to select the better one for natural water bodies. The synthesized DNA sequence was provided by the Integrated DNA Technologies (Coralville, USA). The DNA solution were assembled in Milli-Q water (18.2 MΩ∙cm) prior to the addition of variable volumes of 1 mg L-1 Hg2+ standard solution prepared from a 1000 mg L-1 Hg2+ stock solution. The DNA-functionalized polyacrylamide hydrogels were prepared in 96-well clear microplates and in pH 7 Tris-nitrate buffer solutions. Variables collected in this research include the intensities of fluorescence as functions of solution pH, temperature, individual inorganic ligand (Cl-, SO42-, HCO3-, H2PO4-) concentrations and the Suwannee River Fulvic Acid concentrations. The DNA-functionalized hydrogel sensor was also tested for its response of fluorescence intensities in artificial surface water samples. For the DNA solution, the fluorescence intensities were measured on a Multimode Reader (Infinite 200Pro) equipped with 96-well clear-bottom microplates, at the excitation/emission wavelength of 485/535 nm. For the DNA-functionalized hydrogel, after being stained in 1 mL of 610 nM SYBR Green I solution for 1 hour at 25 ◦C, the fluorescence intensities were determined using a gel documentation system (Alpha Innotech FluorChem FC2) at the excitation wavelength of 365 nm, with a detection limit of 10 nM total Hg2+. Further details on the experimental setup can be found in the Supporting Information for: https://doi.org/10.1016/j.jhazmat.2019.121572. All data were collected in the Ecohydrology Research Group laboratories at the University of Waterloo.

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    This dataset is the definitive set of locality boundaries for the state of Victoria as defined by Local Government and registered by the Registrar of Geographic Names. The boundaries are aligned to Vicmap Property. This dataset is part of the Vicmap Admin dataset series.

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    Major hydrological basins and their sub-basins. This dataset divides the African continent according to its hydrological characteristics. The dataset consists of the following information:- numerical code and name of the major basin (MAJ_BAS and MAJ_NAME); - area of the major basin in square km (MAJ_AREA); - numerical code and name of the sub-basin (SUB_BAS and SUB_NAME); - area of the sub-basin in square km (SUB_AREA); - numerical code of the sub-basin towards which the sub-basin flows (TO_SUBBAS) (the codes -888 and -999 have been assigned respectively to internal sub-basins and to sub-basins draining into the sea)

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    Shapefile detailing classified prairie watersheds (n = 4175) according to physiographic characteristics. These characteristics were assembled from a variety of sources, including remote sensed data and government databases. Variables included climatic (annual precipitation, potential evapotranspiration), physical (slope, elevation), surficial geology, wetland (density, size distribution), and land cover/use data. Watersheds were classified using a hierarchical clustering on principal components analysis. As a result, seven distinct classes of watersheds were identified. The dataset defines two classifications schemes: (1) Integrated Watershed Classification, and (2) Land Cover Watershed Classification. The schemes differ as the latter was performed without climatic variables. As such, the land cover approach is suited for applications where local climate is forced using other data sources (e.g., hydrological modelling). The integrated classification is suited for general applications.The associated manuscript, which includes methods and data sources, can be found here: https://doi.org/10.5194/hess-23-3945-2019

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    During National Science Week on Sunday 26th August 2007, Geoscience Australia opened its doors to the community to showcase a diverse range of work activities. Members of the public had the opportunity to discover how earthquakes are detected, pan for gold, tour the building, view Australia in 3D, become a seafloor detective and talk to the people who work for Australia's national geoscience research organisation. The photographs of that open day have been converted into thumbmail images and are available on the GA web site.

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    Physiographic maps for the CIS and Baltic States (CIS_BS), Mongolia, China and Taiwan Province of China. Between the three regions (China, Mongolia, and CIS_BS countries) DCW boundaries were introduced. There are no DCW boundaries between Russian Federation and the rest of the new countries of the CIS_BS. The original physiographic map of China includes the Chinese border between India and China, which extends beyond the Indian border line, and the South China Sea islands (no physiographic information is present for islands in the South China Sea). The use of these country boundaries does not imply the expression of any opinion whatsoever on the part of FAO concerning the legal or constitutional states of any country, territory, or sea area, or concerning delimitation of frontiers. The Maps visualize the items LANDF, HYPSO, SLOPE that correspond to Landform, Hypsometry and Slope.

  • The stable isotope signatures of walleye will be analyzed to compare food web structure, at different sites above and below the Dunnville dam, located in southern Grand River. The lengths and weights of walleye will be measured to compare the condition factor of walleye at different sites above and below the Dunnville dam. Walleye were caught in the southern Grand River at three sites using a boat electrofisher, and their lengths and weights were measured on shore using a ruler and a scale respectively. Muscle tissue samples for future stable isotope analysis were also collected on shore. Stable isotope signatures (that is delta15N and delta13C) will be measured using mass spectrometry at the University of Waterloo Environmental Isotope Lab.

  • The water quality data for downstream of Maumee River (Waterville station) has been collected from the National Center for Water Quality Research housed at the Heidelberg University. Data obtained from United States Census Bureau websites include; population of county, detergent use, fertilizer use, land use, crop area, and livestock count. These data have been used as inputs for the parsimonious model.

  • The Weather Research and Forecasting model Version 3.6.1 ( the model source code is accessible from http://www2.mmm.ucar.edu/wrf/users/downloads.html) was used to simulate the historical (2000-2015) and projected climate (RCP8.5) over western Canada with a convection-permitting resolution of 4 km. The WRF model is fully compressible and nonhydrostatic and uses the Advanced Research WRF (ARW) dynamical solvers. The model domain is composed of 699 x 639 grid points with 4-km horizontal resolution to cover western Canada. The atmospheric simulation consists of hourly historical climate scenario (ctl-wrf-wca) from 2000-10-01 to 2015-09-30 at 4km spatial resolution. The model simulations employed several parameterization schemes, including Thompson microphysics scheme (Thompson et al., 2008), the Yonsei University (YSU) planetary boundary layer scheme, the Noah land surface model (Chen and Dudhia, 2001), and the CAM3 radiative transfer scheme (Collins et al., 2004). The deep cumulus parameterization was turned off because with a 4-km horizontal resolution the model can explicitly resolve deep convection and simulate convective storms. The convection-permitting model produces precipitation more realistically by directly resolving convections. Subgrid cloud cover was also disabled. The control experiment (CTL), a retrospective/control simulation, aimed to reproduce the current climate statistics in terms of variability and mean state from October 1, 2000 to 30 September 2015. This control simulation was forced using 6-hourly 0.7 degree ERA-Interim reanalysis data (Dee et al., 2011) directly. The following atmospheric variables are currently available for western Canada: grid scale precipitation, temperature, latent heat flux, upward heat flux, upward moisture flux, downward long wave flux, downward short wave flux, surface pressure, mixing ratio, U component of the 10-m wind ( along grid x axis) and V-component of the 10-m wind ( along grid Y axis). These data are in NetCDF format and can be downloaded via the Cuizinart Platform (http://cuizinart.io).

  • The proposed study uses document analysis, policy Delphi surveys, and interviews as data collection methods to qualitatively analyze water governance in the western Lake Erie basin and identify drivers of eutrophication. Documents related to nutrient management in the western Lake Erie basin will be analyzed to understand the existing water governance system. Documents reviewed may include legislation, agreements, guidance documents, progress reports, assessments of progress, and action plans from the Canada, Ontario, U.S., and state governments. These documents will be collected using internet and library sources, and through requests to appropriate bodies when necessary. The document analysis will inform the development of questions for the policy Delphi surveys and the semi-structured interviews. The policy Delphi survey will consist of two rounds of surveys with experts to identify and understand the drivers of eutrophication in the western Lake Erie basin, and whether they are considered by the water governance system. Participants of the policy Delphi survey will be selected with purposive sampling, based on identifying experts on nutrient management and water governance in the western Lake Erie basin. The results of the policy Delphi surveys will inform the development of questions for the semi-structured interviews, as well as potential participants. The interviews will be an in-depth investigation of selected external drivers of eutrophication in the western Lake Erie basin, and how they are accounted for (or not) by the governance system, and to explore opportunities for innovation in the water governance system. Semi-structured interviews will be conducted with the individuals involved in or associated with water governance in the western Lake Erie basin, and individuals identified through the policy Delphi surveys as being, or associated with, an external driver of eutrophication in the western Lake Erie basin. Participants may include representatives from government agencies, non-governmental organizations, and academia.