Glossary of NAWQA Terminology

ALMN

- Official abbreviation of the Allegheny and Monongahela Study Unit.

Basic Fixed Site

- Sites on streams at which streamflow is measured and samples are collected to assess to the broad-scale spatial and temporal character and transport of inorganic constituents of streamwater in relation to hydrologic conditions and environmental settings. Data from these sites are the primary source of information for meeting water-column assessment objectives for temperature, salinity, suspended sediment, major ions and metals, nutrients, and organic carbon. Three types of water-column sampling activities -- continuous monitoring, fixed-interval sampling, and extreme-flow sampling -- are conducted for 2 years during each cycle of investigation. Reach assessments of ecological conditions and bed-sediment and tissue sampling also are conducted at these sites.

Bed-Sediment and Tissue Studes

- Assessment of concentrations and distributions of trace elements and hydrophobic organic contaminants in streambed sediment and tissues of aquatic organisms to identify potential sources and to assess spatial distribution. Studies are divided into two-phases -- the Occurrence Survey and the Spatial Distribution Survey.

DTH (depositional-targeted habitat)

- See Semi-quantitative sampling. Abbreviated as a "D" in the invertebrate tables.

Environmental setting

- Land areas characterized by a unique, homogeneous combination of natural and human-related factors, such as row-crop cultivation on glacial till soils.

DMS

- Degree (2-digit) Minutes (2-digit) Seconds (2-digit), used for Latitude and Longitude.

Fixed-Site Reach Assessments

- One-time assessments of biological communities and habitat conditions of a stream reach at all Basic and Intensive Fixed Sites.

Indicator Site

- Stream sampling sites located at outlets of drainage basins with homogenous land use and physiographic conditions. Basins are chosen to be as large and representative as possible while still encompassing primarily one environmental setting (typically 19-193 mi²)

Integrator Site

- Stream sampling sites located downstream of drainage basins that are large and complex and often contain multiple environmental settings. Most Integrator Sites are on major streams with drainage basins that include a substantial part of the Study-Unit area.

Intensive Fixed Site

- Basic Fixed-Sites with increased sampling frequency during selected seasonal periods and analysis of dissolved pesticides for one year.

Land-Use Studies

- Investigations of the concentrations and distibution of water-quality constituents in recently recharged ground-water (generally less than 10 years old) associated with the most important regionally significant environmental settings of land use and hydrogeologic conditions in each Study Unit.

NAWQA

- Official abbreviation of the National Water-Quality Assessment Program.

Netcodes

- National NAWQA study-type codes (used to compare equivalent studies between Study Units).

Netdesc

- National NAWQA standard definition for study types, defines the Netcodes.

Occurrence Survey

- The first phase of study of trace elements and hydrophobic organic contaminants in streambed sediment and tissues of aquatic organisms to determine which target constituents are comment and important to water-quality conditions in each Study Unit. Typically all Basic and Intensive Fixed Sites and 5-10 additional sites are sampled.

QMH (qualitative multihabitat sampling)

- See Qualitative sampling. Abbreviated as a "Q" in the invertebrate tables.

Qualitative sampling (qualitative multihabitat (QMH) sampling)

- Qualitative sampling involves collecting invertebrates from as many different instream habitats as possible and is intended to provide a list of taxa present in the sampling reach.

Reach

- The communities and habitat conditions associated with a site are characterized within a defined length of the stream referred to as the "sampling reach." This approach provides a common spatial scale upon which to assess community and habitat characteristics.

RTH (richest-targeted habitat)

- See Semi-quantitative sampling. Abbreviated as a "R" in the invertebrate tables.

Semi-quantitative sampling

- Semi-quantitative sampling is intended to provide a measure of the relative abundance of each taxon present in two contrasting habitat types within the sampling reach. The two habitat types for sampling benthic invertebrate communities include: (1) a habitat supporting faunistically richest community of benthic invertebrates (richest-targeted habitat, RTH), usually a fast-flowing, coarse-grained riffle; and (2) a fine-grained, organically rich depositional habitat (depositional-targeted habitat, DTH), usually a pool.

Spatial Distribution Survey

- Extension of the Occurrence Survey for bed sediments and tissues to improve geographic coverage with particular emphasis on assessment of priority constituents identified in the Occurrence Survey.

Study Unit

- A major hydrologic system of the United States in which NAWQA studies are focused. Study Units are geographically defined by a combination of ground- and surface-water features and usually encompass more than 10,000 km² of land area. The NAWQA design is based on an assessment of 59 Study Units, which collectively cover a large part of the Nation, encompass the majority of population and water use, and include diverse hydrologic systems that differ widely in natural and human factors that affect water quality.

Study-Unit Survey

- Broad assessment of the water-quality conditions of the major aquifer systems of each Study Unit.

Sucodes

- Study Unit codes derived from combining the Study-Unit abbreviation and the appropriate Netcode.

Synoptic Studies

- Short-term investigations of specific water-quality conditions during selected seasonal or hydrologic periods to provide improved spatial resolution for critical water-quality conditions compared to Fixed-Site sampling. For the period and conditions sampled, they assess the spatial distribution of selected water-quality conditions in relation to causative factors, such as land use and contaminant sources, through mass-balance analysis or sources and transport.

The below listed codes are necessary to compare equivalent data between National NAWQA Study Units and were established on the national level to provide a consistent framework with which to compare the individual NAWQA basins. See the above listed definitions for explanation of the table headers.

Return to the Water Resources of Pennsylvania Home Page
or go directly to:





The URL for this page is http://pa.water.usgs.gov /almn/almn_glossary.html
Please note our privacy statement and disclaimer
Accessibility

Answers to many common questions can be found on our
Frequently Asked Questions (FAQ) page. Please direct content comments
or questions to:

Information Specialist U.S. Geological Survey 215 Limekiln Road New Cumberland, PA 17070-2424	Phone: (717) 730-6916 FAX: (717) 730-6997 Email: is_pa@usgs.gov
or contact:
Director, USGS Pennsylvania Water Science Center U.S. Geological Survey 215 Limekiln Road New Cumberland, PA 17070-2424	Phone: (717) 730-6960 FAX: (717) 730-6997 Email: dc_pa@usgs.gov

Please direct web related comments to webmaster@pa.water.usgs.gov

caww51