Nitrogen Loads, Yields, and Associated Field Data Collected During Baseflow Conditions and Site Attributes for Small Basins Draining to Long Island Sound

Dates

Publication Date: 2023-10-30
Time Period: 2022-04-24
Time Period: 2022-04-25
Time Period: 2022-06-30
Time Period: 2022-07-01

Citation

Barclay, J.R., Laabs, K.L., and Mullaney, J.R., 2023, Nitrogen loads, yields, and associated field data collected during baseflow conditions and site attributes for small basins draining to Long Island Sound: U.S. Geological Survey data release, https://doi.org/10.5066/P99IAXUI.

Summary

During the spring and summer of 2022, the U.S. Geological Survey collected water-quality samples for nutrient analysis at 45 stations across the state of Connecticut and adjacent areas of New York and Rhode Island to better understand the groundwater discharge component of nitrogen loading to the Long Island Sound. The targeted stations were located in small drainage basins (less than 50 square kilometers) in the southern portion of the Long Island Sound watershed. Sites were selected randomly from groups based on expected drivers or controls on baseflow nitrogen loads. Factors used in the grouping included four metrics calculated for the upstream watershed: percent impervious cover, septic system density, percent agricultural or turf [...]

Summary

During the spring and summer of 2022, the U.S. Geological Survey collected water-quality samples for nutrient analysis at 45 stations across the state of Connecticut and adjacent areas of New York and Rhode Island to better understand the groundwater discharge component of nitrogen loading to the Long Island Sound. The targeted stations were located in small drainage basins (less than 50 square kilometers) in the southern portion of the Long Island Sound watershed. Sites were selected randomly from groups based on expected drivers or controls on baseflow nitrogen loads. Factors used in the grouping included four metrics calculated for the upstream watershed: percent impervious cover, septic system density, percent agricultural or turf grass land cover, and percent coarse-grained stratified sediments. The water-quality samples and instantaneous discharge measurements were collected under baseflow conditions during two separate synoptic sampling events, one in the nongrowing season (April 2022) and one in the growing season (June and July 2022). Instantaneous discharge measurements were collected in addition to water-quality samples to enable the calculations of nitrogen loads and yields. The water-quality samples were analyzed for physical properties and concentrations of chloride, nutrient species, and dissolved organic carbon; some analyses were performed past analytical method holding times. This data release includes site characteristics and geospatial data for potential and final (selected) sites, as well as field data, analytical results, and calculated nitrogen loads and yields for the final sites. Column names, units and descriptions are provided in data_dictionary.txt and a lookup table for method codes is provided in MethodLookupTable.txt. Note that many station identifiers (site_no) have a leading "0" that should be retained.

Contacts

Point of Contact :: Janet R Barclay
Process Contact :: Janet R Barclay, Kaitlin L Laabs
Originator :: Janet R Barclay, Kaitlin L Laabs, John R Mullaney
Metadata Contact :: Janet R Barclay
Publisher :: U.S. Geological Survey
Distributor :: U.S. Geological Survey - ScienceBase
SDC Data Owner :: New England Water Science Center
USGS Mission Area :: Water Resources

Attached Files

sorting

Metadata First

Recent First

Alphabetical

Click on title to download individual files attached to this item.

data_dictionary.txt		20.58 KB	text/plain
FieldLabData.txt		559 KB	text/plain
FinalSiteAttributes.txt		5.59 KB	text/plain
HoldingTimes.txt		1.62 KB	text/plain
LoadsYieldsData.txt		20 KB	text/plain
LongIslandSound_Baseflow_metadata.xml Original FGDC Metadata	View	49.9 KB	application/fgdc+xml
MethodLookupTable.txt		3.85 KB	text/plain
PotentialSiteAttributes.txt		40.72 KB	text/plain
QC_Data.txt		28.08 KB	text/plain

Shapefile: FinalSiteWatersheds.zip
FinalSiteWatersheds.dbf		11.28 KB
FinalSiteWatersheds.prj		167 Bytes
FinalSiteWatersheds.shp		109.9 KB
FinalSiteWatersheds.shx		460 Bytes

Shapefile: PotentialSites.zip
PotentialSites.dbf		146.17 KB
PotentialSites.prj		167 Bytes
PotentialSites.shp		10.87 KB
PotentialSites.shx		3.18 KB

Shapefile: FinalSites.zip
FinalSites.dbf		11.28 KB
FinalSites.prj		167 Bytes
FinalSites.shp		1.33 KB
FinalSites.shx		460 Bytes

Shapefile: PotentialSiteWatersheds.zip
PotentialSiteWatersheds.dbf		62.52 KB
PotentialSiteWatersheds.prj		167 Bytes
PotentialSiteWatersheds.shp		8.76 MB
PotentialSiteWatersheds.shx		3.18 KB

Purpose

The purpose of this data release is to present data on growing and non-growing season nitrogen loads and yields under baseflow conditions, as well as site characteristics, for small watersheds within the lower Long Island Sound watershed. These data are useful for identifying broad spatial and temporal patterns of nitrogen inputs to freshwater and coastal ecosystems.

Nitrogen Loads, Yields, and Associated Field Data Collected During Baseflow Conditions and Site Attributes for Small Basins Draining to Long Island Sound

Dates

Citation

Summary

Summary

Contacts

Attached Files

sorting

Metadata First

Recent First

Alphabetical

Purpose

Map

Spatial Services

Communities

Tags

Provenance

Additional Information

Identifiers

Shapefile Extension

Shapefile Extension

Shapefile Extension

Shapefile Extension

Item Actions

Use Item

View Item as ...

Save Item as ...

View Item...

Dates

Citation

Summary

Summary

Contacts

Attached Files sorting Metadata First Recent First Alphabetical

Purpose

Map

Spatial Services

Communities

Tags

Provenance

Additional Information

Identifiers

Shapefile Extension

Shapefile Extension

Shapefile Extension

Shapefile Extension

Item Actions

Use Item

View Item as ...

Save Item as ...

View Item...

Attached Files

sorting

Metadata First

Recent First

Alphabetical