From: kiran (Kiran R)
X-URL: http://www.nhq.nrcs.usda.gov/land/meta/m2163.htmlct/EIan0002.htmt.htmltmlm
Subject: Changes in wetlands acreage on non-federal land - m2163.html
Status: R
[USEMAP]
[LINK]
Product Title:
Changes in Wetland Acreage on Non-Federal Land, by Region, 1982 to
1992
Description:
This graphic includes bar diagrams and pie charts for the U.S. and
NRCS regions. The bar diagrams represent gains and losses of
wetland acres on non-Federal land from 1982 to 1992, and the pies
break out the wetland losses into four major land uses --
development, agriculture, deepwater conversions, and other
miscellaneous causes. Deepwater is conversion of wetlands to
reservoirs, ponds, rivers (meanders), open water estuaries, or
open water marine habitats; Development refers to urban, suburban,
and industrial developments, but does not include farmstead and
agribusiness (barns, sheds, silos, etc.) development in rural
locations. Agriculture includes cropland, pastureland and
farmsteads. Wetlands include all palustrine system categories, all
estuarine vegetated categories, all marine, estuarine none/other,
riverine and lacustrine with cover/use codes less than 900, all
estuarine none/other and lacustrine none/other with less than 2
acres, and all emergent nonpersistent less than 40 acres.
Palustrine wetlands made up 93.9% and estuarine wetlands made up
4.6% of all wetlands.
Uses of this Product:
This graphic is useful as a quick picture of the U.S. regions
which experienced larger or smaller changes in wetland acreages
between 1982 and 1992 and, of those that lost wetlands, to what
land use category they are being lost.
Cautions for this Product:
The pies represent wetland losses only and disregard gains made in
each region. Regional pies are proportionately scaled to each
other, but the U.S. pie is not scaled to the regional pies.
_________________________________________________________________
SOURCES
Source:
National Resources Inventory, 1992
Distributor:
USDA-NRCS-RID
Reliability:
NRI sample data are generally reliable at the 95% confidence
interval for state and certain substate geographic level analyses.
When provided, refer to the estimated margins of error to
determine suitability of the data for a particular purpose. NRI
maps reflect national patterns rather than site-specific
information.
_________________________________________________________________
LAYERS
Aggregate Layer
Layer Type
NRCS Region Polygons
Polygon
Other Layers Displayed
Layer Type
State
Polygon
_________________________________________________________________
DEFINITIONS
Deepwater habitat :
Any open water area in which the mean water depth exceeds 6.6 feet
in nontidal areas or at mean low water in freshwater tidal areas,
or is covered by water during extreme low water at spring tides in
salt and brackish tidal areas, or covers the deepest emerging
vegetation, whichever is deeper [USFWS]
Estuarine system :
Deepwater tidal habitats and adjacent tidal wetlands that are
semienclosed by land but have open, partly obstructed, or sporadic
access to the open ocean, and in which ocean water is at least
occasionally diluted by freshwater runoff from the land. [USFWS]
Lacustrine system :
Wetlands and deepwater habitats with all of the following
characteristics: (1) situated in a topographic depression or a
dammed river channel; (2) lacking trees, shrubs, persistent
emergents, emergent mosses or lichens with greater than 30 percent
area coverage; and (3) total area exceeds 8 ha (20 acres). [USFWS]
Land cover/use :
A term that includes categories of land cover and categories of
land use. Land cover is the vegetation or other kind of material
that covers the land surface. Land use is the purpose of human
activity on the land; it is usually but not always related to the
land cover. The NRI uses the term (land cover/use) to identify the
categories that account for all the surface area in the United
States [BS-1982; NRI-92]
Marine System :
The open ocean overlying the continental shelf and its associated
highenergy coastline. Marine habitats are exposed to the waves and
currents of the open ocean and the water regimes are determined
primarily by the ebb and flow of oceanic tides. [U.S.FWS]
Non-Federal land :
Includes all land and water areas where the ownership is by
private, municiple, county or parish, state, Indian tribal,
individual trust, the Tennessee Valley Authority, or areas under
temporary control of a Federal, state, county or municiple agency
or government for foreclosure or nonpayment of taxes.
NRCS Regions :
The six geographical areas of the U.S. by which the National
Resources Conservation Service administers itself. The states
included in each region are as follows: East Region: Connecticutt,
Deleware, Maryland, Maine, Massachusetts, New Hampshire, New
Jersey, New York, Pennsylvania, Rhode Island, Vermont, West
Virginia; Midwest Region: Iowa, Illinois, Indiana, Michigan,
Minnesota, Missouri, Ohio, Wsconsin; Northern Plains Region:
Colorado, Kansas, Montana, North Dakota, Nebraska, South Dakota,
Wyoming; South Central Region: Arkansas, Louisiana, Oklahoma,
Texas; Southeast Region: Alabama, Florida, Georgia, Kentucky,
Mississippi, North Carolina, Puerto Rico, South Carolina,
Tennessee, Virginia, US Virgin Islands; West Region: Alaska,
Arizona, California, Hawaii, Idaho, Nevada, New Mexico, Oregon,
Utah, Washington, US islands of the Pacific Basin
Palustrine system :
All non-tidal wetlands dominated by trees, shrubs, persistent
emergents, emergent mosses, or lichens, and all such wetlands that
occur in tidal areas where salinity due to ocean derived salts is
below 0.5 percent [U.S.FWS]
Wetland :
Areas that have a predominance of hydric soils and that are
inundated or saturated by surface or ground water at a frequency
and duration sufficient to support, and under normal circumstances
do support, a prevalence of hydrophytic vegetation typically
adapted for life in saturated soil conditions. [NFSAM]
_________________________________________________________________
PRODUCT INFORMATION
Product ID:
2163
Production Date:
7/30/97
Product Type:
Arc/Info Map
Geographic Coverage:
Contiguous US, HI, PR, US VI
Key Words:
Wetland, Change, Palustrine, Estuary
_________________________________________________________________
For additional information contact the Resource Assessment and
Strategic Planning Division. Please include the Product ID you are
inquiring about. rasp@nhq.nrcs.usda.gov or 1400 Independence Avenue
SW - Room 5210 - P.O. Box 2890 - Washington D.C. 20013