The Ocean Environment Essay examples -- Marine Environment Essays

Ocean Environment     The sea is the most obvious feature of the earths get along.Approximately seventy percent of this surface is covered by urine, in one way oran early(a). Beneath this water are the familiar sands of the beaches, bottoms ofbays, and the inshore ocean. Farther offshore this water covers an amazingsubmarine topography of underwater canyons, trenches, mountains, and plains.Unlike the continents, which are physically separated from one another, theoceans are continuous and interconnected. Since the "world ocean iscontinuous"(M.J. Keen) it has similar characteristics throughout. In the early1870s oceanographers collected seawater samples from all of the seas of theworld at a variety of depths. When analyzed, the samples were found to obligequite similar characteristics. These findings convinced many that a method ofstudy was needed. The study of oceans was named oceanography.     Density, salinity, and temperature are very important concepts in thestudy of oceanography. The salinity and temperature of the water influence itsdensity, and the differences in density are the study factor in understandingthe formation of currents and the positions of water masses in the sea. Inaddition, temperature and salinity play major roles in influencing thedistribution of plants and animals.     The sediments of the sea blow out of the water may be divided into lithogenous,hydrogenous, biogenous, and cosmogenous sediments. Lithogenous sediments arethe major sediments on the ocean floor. They are derived from the chemical andmechanical weathering of rocks. Biogenous sediments are composed primarily ofthe protecting(prenominal) outter covering of small marine animals and plants. If theseremains comprise at least thirty percent of the sediment it is called an "ooze"."Oozes" were named for the types of organisms that formed them. Hydrogenoussediments form as a result of the ch emical reactions that occur in the seawater.These reactions result in the formation of small particles, which are depositedon the sea floor. Currents move these particles and cause them to collide withthe other particles. If many of these collisions occur they may form nodules.Nodules are found on some portions of the deep-sea floor. The sediment typefrequently determines the type of organ... ...discarge of oil fromships, and the growing of emergency response systems to oil pollutionaccidents have contributed to the decline of ship-based souces of oil pollutionover the last two decades. The moratorium on dumping of radioactive pay off atsea under the London Dumping Convention also represents another response toconcerns about the risks posed by such diposal. Some regions have concludedagreement which ban dumping of any radioactive waste at sea. In theMediterranean and Red Sea, all discharge of oily soft-witted from ships is alsobanned.     The differences betw een terrestial regions are well known. Less wellknown are the features that distingush the Atlantic from the Pacific Ocean, orthe coast of South America from those of grey Africa. Regardless of this,the various regions of the worlds oceans are all affected by human activity,with pollution and harvesting of resouces of resouces being common to all seasand oceans. The various marine resources, as well as the extent of humanimpacts on them, are examined region by region, illustrating hos stresses on themarine environmet treatened the very resistance of some habitats and species.