“Oceans, Coasts, and Fisheries” Unit 3 “Oceans, Coasts, and Fisheries”

Oceans on the Earth 71% of Earth’s surface is covered by oceans Composition of ocean water is as follows: 96% water 3.5% salt (mostly NaCl – sodium chloride) .5% consists of trace amounts of Sulfate, Mg, Ca, K, and Bicarbonate

Oceans on the Earth As depth increases, pressure _________. Why? As depth increases, temperature __________. Why? As depth increases, salinity _________. Why? As depth increases, light penetration decreases

Movement of Ocean Water Currents – large volume of ocean water that flows due to changes in density, temperature, gravity, and wind Horizontal currents: usually due to wind Vertical currents: due to density, temperature, and gravity

Movement of Ocean Water Upwelling - vertical flow of cold, dense water to the surface; occurs in areas where horizontal currents diverge Downwelling – vertical flow of warm, less dense water toward the ocean bottom; occurs in areas where horizontal currents converge

Movement of Ocean Water It is important to understand the interconnectedness of air currents (wind) and ocean currents Air currents affect horizontal ocean currents and horizontal ocean currents affect vertical ocean currents Therefore, a change in meteorological conditions can affect/change ocean conditions

Ocean’s Vertical Zones

Ocean’s Zones Continued

Ocean Currents Summary http://www.youtube.com/watch?v=Hu_Ga0JYFNg&feature=related http://www.youtube.com/watch?v=L9zjmC8InKA&feature=related http://www.youtube.com/watch?v=FuOX23yXhZ8&feature=channel

Marine Habitats The ocean contains a great variety of species that include invertebrates and vertebrates There are two categories of marine habitats: Benthic: the ocean bottom in either shallow or deep water Pelagic: the open ocean

Marine Habitats The majority of marine ecosystems are Benthic, but there are also a few found in the Pelagic habitat Coral Reef Tide Pool Salt Marsh Mangrove Forest Deep Ocean Kelp Forest

Human Impact on the Ocean The ocean is used in much the same way as is the lithosphere Transportation, Resource Extraction (both biotic and abiotic), Tourism etc. are all ways in which people use oceans As a result of the above-mentioned ocean usage, pollution and overexploitation occurs

Pollution and Overexploitation Pollution – any unwanted substance that is released into the ocean as a result of resource extraction, transportation, or tourism Overexploitation – is the taking of too many individuals of a marine species thereby making it impossible for those remaining to replenish the numbers lost through fishing Bycatch – non target marine species are killed as a result of becoming entangled in nets meant to catch another marine species https://oceantoday.noaa.gov/reducingbycatch/

Examples of Pollution & Overexploitation http://www.upi.com/Top_News/International/2010/02/14/Canada-to-close-ports-due-to-over-fishing/UPI-74111266192280/ http://marine-conservation.suite101.com/article.cfm/what_is_bycatch http://www.buzzle.com/articles/ocean-pollution-causes.html

MPA’s & MR’s Marine Protected Area (MPA): Geographic area with discrete boundaries that has been designated to enhance the conservation of marine resources. This includes MPA-wide restrictions on some activities such as oil and gas mining and the use of zones such as fishery and ecological reserves to provide higher levels of protection. Marine Reserve: A zone in which some or all of the biological resources are protected from removal or disturbance; encompasses both fishery and ecological reserves.