<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="BC-433" name="Benthic Macroalgae" parent="BC-394" scope="Biotic Subclass: Aquatic beds dominated by macroalgae attached to the substrate, such as kelp (Figure 8.14), intertidal fucoids, and calcareous algae. ..."/><bt><term thcode="62" code="BC-394" name="Aquatic Vegetation Bed" parent="BC-389" scope="Biotic Class: This class includes subtidal or intertidal bottoms and any other areas characterized by a dominant cover of rooted vascular plants, attached macroalgae, or mosses, which are usually submersed in the water column or floating on the surface. ..."/><term thcode="62" code="BC-389" name="Benthic/Attached Biota" parent="BC-C002" scope="Biotic Setting: This biotic setting describes areas where biota lives on, in, or in close association with the seafloor or other substrates (e.g., pilings, buoys), extending down into the sediment to include the sub-surface layers of substrate that contain multi-cellular life. ..."/><term thcode="62" code="BC-C002" name="Biotic" 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="BC-558" name="Calcareous Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by calcareous algae that incorporate calcium carbonate into their tissues, support their own weight, and have an upright growth form. ..."/><term thcode="62" code="BC-559" name="Canopy-Forming Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by canopy-forming algae that have complex growth forms with holdfasts and well-defined stipes and blades. ..."/><term thcode="62" code="BC-560" name="Coralline/Crustose Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by coralline or crustose algae that incorporate calcium carbonate into their tissues and form crusts on the substrate in many marine environments. ..."/><term thcode="62" code="BC-561" name="Filamentous Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by filamentous algae that have a growth form consisting of fine filaments or strands with no blades or stipes. ..."/><term thcode="62" code="BC-562" name="Leathery/Leafy Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by leathery/leafy algae have a variety of specialized tissues (including thalli) that resemble stems and leaf-like blades. ..."/><term thcode="62" code="BC-563" name="Mesh/Bubble Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by mesh or bubble algae that form small, generally spherical masses attached to the benthos. ..."/><term thcode="62" code="BC-564" name="Sheet Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by sheet (thallose) algae that form thin, undifferentiated, membranous sheets with no stipe or blades. Growth in these algae occurs in two directions. The sheets can be as thin as a single cell."/><term thcode="62" code="BC-565" name="Turf Algal Bed" parent="BC-433" scope="Biotic Group: Areas dominated by turf algae that represent a multi-specific assemblage of diminutive, often filamentous, algae that attain a canopy height of only 1 - 10 millimeters (see Steneck 1988 for review). ..."/></nt></descriptor>