Filters: Types: Citation (X) > Types: OGC WMS Service (X) > partyWithName: U.S. Geological Survey - ScienceBase (X) > partyWithName: Office of Planning and Programming (X)
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This dataset is comprised of water quality data and benthic macroinvertebrate data collected from basins in Colorado, USA, and Finland. The data includes ancillary water quality characteristics but also a suite of trace metals observed at each site. Also included are modeled outputs that characterize the bioavailability of each trace metal to a biotic ligand. These data were used to explore the importance of metal toxicity and pH as stressors on benthic macroinvertebrates characterized as the number of unique Ephemeroptera + Plecoptera + Trichoptera genera observed at each site. An interpretive summary of the work follows. One of the primary goals of biological assessment of rivers is to identify whether contaminants...
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Benthic Macroinvertebrates,
Bioavailability,
Colorado,
Europe,
Finland,
Widespread nitrate contamination of groundwater in agricultural areas poses a major challenge to sustainable water resources. Efficient analysis of nitrate fluxes across large regions also remains difficult. This study introduces a method of characterizing nitrate transport processes continuously across regional unsaturated zones and groundwater based on surrogate, machine-learning metamodels of an N flux process-based model. The metamodels used boosted regression trees (BRTs) to relate mappable variables to parameters and outputs of a “vertical flux method” (VFM) applied in the Fox-Wolf-Peshtigo (FWP) area in Wisconsin. In this context, the metamodels are upscaling the VFM results throughout the region, and the...
The United States Geological Survey’s (USGS) SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was developed to aid in the interpretation of monitoring data and simulate water-quality conditions in streams across large spatial scales. SPARROW is a hybrid empirical/process-based mass balance model that can be used to estimate the major sources and environmental factors that affect the long-term supply, transport, and fate of contaminants in streams. The spatially explicit model structure is defined by a river reach network coupled with contributing catchments. The model is calibrated by statistically relating watershed sources and transport-related properties to monitoring-based streamflow...
The ascii grids represent regional probabilities that groundwater in a particular location will have dissolved oxygen (DO) concentrations less than selected threshold values representing anoxic groundwater conditions or will have dissolved manganese (Mn) concentrations greater than selected threshold values representing secondary drinking water-quality contaminant levels (SMCL) and health-based screening levels (HBSL) for water quality. The probability models were constrained by the alluvial boundary of the Central Valley to a depth of approximately 300 meters (m). We utilized prediction modeling methods, specifically boosted regression trees (BRT) with a Bernoulli error distribution within a statistical learning...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted Regression Trees,
California,
Central Valley, California,
Domestic Well Water Use,
Drinking Water Use,
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