Search results
Results from the WOW.Com Content Network
The distinction between demersal species of fish and pelagic species is not always clear cut. The Atlantic cod (Gadus morhua) is a typical demersal fish, but can also be found in the open water column, and the Atlantic herring (Clupea harengus) is predominantly a pelagic species but forms large aggregations near the seabed when it spawns on banks of gravel.
Demersal zone – the zone at or near the bottom of a sea or lake. Inhabitants of the demersal zone feed off the bottom or off other demersal fish. See also pelagic zone. Demersal fish – fish that live in the demersal zone. Examples are cod, flounder and snapper. Compared to pelagic fish, demersal fish contain little oil. See also bottom feeder.
Similarly, an organism living in a demersal habitat is said to be a demersal organism, as in demersal fish. Pelagic habitats are intrinsically ephemeral, depending on what ocean currents are doing. The land-based ecosystem depends on topsoil and fresh water, while the marine ecosystem depends on dissolved nutrients washed down from the land.
Ocean surfaces occupy 72% of the Earth's total surface. They can be divided into surfaces of the relatively shallow and nutrient rich coastal areas above the continental shelves (light blue), and surfaces of the more expansive and relatively deeper but nutrient poor ocean that lies beyond (deep blue).
Territorial waters and claimed exclusive economic zone of Indonesia The Indonesian archipelagic baselines pursuant to article 47, paragraph 9, of the UNCLOS. The territorial waters of Indonesia are defined according to the principles set out in Article 46 of the United Nations Convention on the Law of the Sea. Their boundary consists of ...
It is part of the larger Indo-Pacific, which includes the tropical Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia. The Western Indo-Pacific may be classified as a marine realm , one of the great biogeographic divisions of the world's ocean basins, or as a subrealm of the ...
The design requirements of a bottom trawl are relatively simple, a mechanism for keeping the mouth of the net open in horizontal and vertical dimensions, a "body" of net which guides fish inwards, and a "cod-end" of a suitable mesh size, where the fish are collected.
What links here; Related changes; Upload file; Special pages; Permanent link; Page information; Cite this page; Get shortened URL; Download QR code