<descriptor thcode="62"><thesaurus thcode="62" name="Coastal and Marine Ecological Classification Standard" scope="Categories of ecosystems for coastal, estuarine, and marine environments." creator="FGDC" rights="public domain" date="2017-05-10" codetype="alpha" prefix="cmecs" uri="https://www2.usgs.gov/science/CMECS" tblname="cmecs" root_code="root" contact="pschweitzer"><category><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/></category><altlabel><altlabel>CMECS</altlabel><altlabel>CMECS</altlabel><altlabel>Coastal and Marine Ecological Classification Standard (CMECS)</altlabel><altlabel>Coastal and Marine Ecological Classification Standard (CMECS)</altlabel></altlabel></thesaurus><term thcode="62" code="WC-C011" name="Layer" parent="WC-C001"/><bt><term thcode="62" code="WC-C001" name="Water Column" parent="root"/><term thcode="62" code="root" name="CMECS" scope="Coastal and Marine Ecological Classification Standard: Category terms encompassing waters from the head of tide or inland incursion of ocean salinity to the splash zone of the coasts to the deepest portions of the oceans and the deep waters of the Great Lakes."/></bt><nt><term thcode="62" code="WC-598" name="Estuarine Coastal Lower Water Column" parent="WC-C011" scope="Water Column Layer: Estuarine waters below the pycnocline (or mid-depth) and between the shore and the 4 meter depth contour."/><term thcode="62" code="WC-597" name="Estuarine Coastal Pycnocline" parent="WC-C011" scope="Water Column Layer: Estuarine waters within the pycnocline, between the shore and the 4 meter depth contour."/><term thcode="62" code="WC-595" name="Estuarine Coastal Surface Layer" parent="WC-C011" scope="Water Column Layer: Estuarine waters between the shore and the 4 meter depth contour at the surface of the water column to a depth of a few centimeters."/><term thcode="62" code="WC-596" name="Estuarine Coastal Upper Water Column" parent="WC-C011" scope="Water Column Layer: Estuarine waters above the pycnocline (or the mid-depth) between the shore and the 4 meter depth contour."/><term thcode="62" code="WC-602" name="Estuarine Open Water Lower Water Column" parent="WC-C011" scope="Water Column Layer: Estuarine waters below the pycnocline (or mid-depth), at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-601" name="Estuarine Open Water Pycnocline" parent="WC-C011" scope="Water Column Layer: Estuarine waters within the pycnocline, at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-599" name="Estuarine Open Water Surface Layer" parent="WC-C011" scope="Water Column Layer: Estuarine waters at the surface, at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-600" name="Estuarine Open Water Upper Water Column" parent="WC-C011" scope="Water Column Layer: Estuarine waters above the pycnocline (or mid-depth), at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-606" name="Estuarine Tidal Riverine Coastal Lower Water Column" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters below the pycnocline (or mid-depth), from the land-water interface up to the 4 meter depth contour."/><term thcode="62" code="WC-605" name="Estuarine Tidal Riverine Coastal Pycnocline" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters within the pycnocline, from the land-water interface up to the 4 meter depth contour."/><term thcode="62" code="WC-603" name="Estuarine Tidal Riverine Coastal Surface Layer" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters at the surface, from the land-water interface up to the 4 meter depth contour."/><term thcode="62" code="WC-604" name="Estuarine Tidal Riverine Coastal Upper Water Column" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters above the pycnocline (or mid-depth), from the land-water interface up to the 4 meter depth contour."/><term thcode="62" code="WC-610" name="Estuarine Tidal Riverine Open Water Lower Water Column" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters below the pycnocline (or mid-depth), at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-609" name="Estuarine Tidal Riverine Open Water Pycnocline" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters within the pycnocline, at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-607" name="Estuarine Tidal Riverine Open Water Surface Layer" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters at the surface, at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-608" name="Estuarine Tidal Riverine Open Water Upper Water Column" parent="WC-C011" scope="Water Column Layer: Tidal fresh waters above the pycnocline (or mid-depth), at or beyond the 4 meter depth contour."/><term thcode="62" code="WC-614" name="Marine Nearshore Lower Water Column" parent="WC-C011" scope="Water Column Layer: Marine waters below the pycnocline (or mid-depth), from the land-water interface up to the 30 meter depth contour."/><term thcode="62" code="WC-613" name="Marine Nearshore Pycnocline" parent="WC-C011" scope="Water Column Layer: Marine waters within the pycnocline, from the land-water interface up to the 30 meter depth contour."/><term thcode="62" code="WC-611" name="Marine Nearshore Surface Layer" parent="WC-C011" scope="Water Column Layer: Marine waters at the surface, from the land-water interface up to the 30 meter depth contour."/><term thcode="62" code="WC-612" name="Marine Nearshore Upper Water Column" parent="WC-C011" scope="Water Column Layer: Marine waters above the pycnocline (or mid-depth), from the land-water interface up to the 30 meter depth contour."/><term thcode="62" code="WC-625" name="Marine Oceanic Abyssopelagic Layer" parent="WC-C011" scope="Water Column Layer: The region of the water column that is generally in contact with the abyssal seafloor, except in deep basins and trenches and represents the bottom layer of the ocean, generally from 4,000 meters to 6,000 meters depth. ..."/><term thcode="62" code="WC-624" name="Marine Oceanic Bathypelagic Layer" parent="WC-C011" scope="Water Column Layer: The region where light does not penetrate, rendering the water column totally dark except for bioluminescence, generally from 1,000 meters to 4,000 meters depth. ..."/><term thcode="62" code="WC-622" name="Marine Oceanic Epipelagic Lower Layer" parent="WC-C011" scope="Water Column Layer: Within the Epipelagic Layer, the region below the Epipelagic pycnocline if present (or below mid-depth [100 meters]). ..."/><term thcode="62" code="WC-621" name="Marine Oceanic Epipelagic Pycnocline" parent="WC-C011" scope="Water Column Layer: Within the Epipelagic Layer, the Marine Oceanic Epipelagic Pycnocline is the zone of maximum vertical change in density of the water normally due to a salinity or temperature gradient, which segregates the water column into two distinct layers that are of relatively homogeneous density. ..."/><term thcode="62" code="WC-620" name="Marine Oceanic Epipelagic Upper Layer" parent="WC-C011" scope="Water Column Layer: The Epipelagic Layer is the upper 200 meters of the oceanic water column. ..."/><term thcode="62" code="WC-626" name="Marine Oceanic Hadalpelagic Layer" parent="WC-C011" scope="Water Column Layer: The deepest waters of the globe occur in trenches and deep basins generally at depths greater than 6,000 meters. ..."/><term thcode="62" code="WC-623" name="Marine Oceanic Mesopelagic Layer" parent="WC-C011" scope="Water Column Layer: The region where light is vertically attenuated to below the level required for photosynthesis, generally between 200 meters and 1,000 meters in depth. ..."/><term thcode="62" code="WC-619" name="Marine Oceanic Surface Layer" parent="WC-C011" scope="Water Column Layer: The interface between the atmosphere and the water column, extending to a depth of several centimeters. ..."/><term thcode="62" code="WC-618" name="Marine Offshore Lower Water Column" parent="WC-C011" scope="Water Column Layer: Marine waters below the pycnocline (or mid-depth), between the 30 meter depth contour and the shelf break."/><term thcode="62" code="WC-617" name="Marine Offshore Pycnocline" parent="WC-C011" scope="Water Column Layer: Marine waters within the pycnocline, between the 30 meter depth contour and the shelf break."/><term thcode="62" code="WC-615" name="Marine Offshore Surface Layer" parent="WC-C011" scope="Water Column Layer: Marine waters at the surface, between the 30 meter depth contour and the shelf break."/><term thcode="62" code="WC-616" name="Marine Offshore Upper Water Column" parent="WC-C011" scope="Water Column Layer: Marine waters above the pycnocline (or mid-depth), between the 30 meter depth contour and the shelf break."/></nt></descriptor>