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NOAA Coral Reef Conservation Program, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
A massive structure composed of clusters of oval, table-like mounds constructed by marine polychaete worms in the family Sabellariide. They consist of all sorts of sediments consolidated by a mucoprotein cement produced by the worm. This reef may start in the intertidal zone and extend into the subtidal zone. Some are in deeper water. Unlike the colorful and ornate coral reefs, worm reefs are drab, monotonous and rounded clusters, mounds and platforms that grow upward and outward from the durable substrate from which their colonies develop. Worm reefs offer several ecological benefits. They provide feeding and browsing grounds for a diverse community of marine organisms and an ideal home for attaching plants, sponges and shelter-seeking animals. Also, unlike coral reefs, worm reefs are not restricted to the tropics.
Industry:Natural environment
A statistical technique used to establish the relationship of a dependent variable and one or more independent variables .
Industry:Natural environment
Brown algae belong to the Division Phaeophycophyta, whose approximately 1,500 species are almost exclusively marine. They include the largest of the seaweeds and the kelps. The brown algae have chlorophyll a and c, as well as carotenes and xanthophylls, but the green chlorophyll coloration is masked by the brown and yellow pigments. Brown algae are among the largest photosynthetic organisms on earth. The largest kelps may grow to more than 60 meters in length, forming dense underwater forests in colder waters. Many microscopic brown algae grow as epiphytes on underwater vegetation, forming networks of branched filaments, or broad encrustations. All species are multicellular and do not form colonies. Their life cycles are complex, involving alternation of generations. In general, they are not free-floating organisms, but are attached to rock, coral, or other firm surfaces. Sargassum weed, however, is a floating brown algae that stays afloat by producing gas-filled bladders.
Industry:Natural environment
Having separate sexes. Individuals within the species contain only one or the other of male and female reproductive systems.
Industry:Natural environment
In taxonomy, the nominal species that is the name-bearing type of a nominal genus or subgenus.
Industry:Natural environment
Speciation when a single, widespread population is divided by (1) the emergence of an extrinsic barrier, (2) extinction of intervening populations, or (3) migration of some individuals into a separate region.
Industry:Natural environment
The elimination of undigested food materials from an organism.
Industry:Natural environment
The total amount or weight of organic matter created by photosynthesis over a defined time period (total product of photosynthesis).
Industry:Natural environment
