Continental Shelf Biome
Geologically, continental shelves are parts of continents that extend below sea level to depths of 100 to 200 m (325-650 ft) [world average is - 132 m (-430 ft)]. Continental shelves slope gradually seaward toward continental margin, where an abrupt break in slope marks the edge of a continent is and forms a steep escarpment, the continental slope. The continental slope extends to depths of 3,000 m (10,000 ft) or more, where continental rock meets the oceanic rock that composes the sea floor.... The continental shelf biome occurs on and above the shelves from the low-tide mark (or beginning of subtidal zone) seaward to the shelf edge or continental slope. This is the neritic zone of the ocean, and it is positioned between and influenced by the coastal zone and the deep sea. Freshwater and nutrients from the land pass into the waters of the continental shelf directly from surface runoff. Many of the animals of the shelf biome spend part of their life cycle in sheltered coastal waters.... This chapter continues to discuss several biotic aspects of the continental shelf biome.