BIOL 317 1st Edition Lecture 8 Outline of Last Lecture - Climate Outline of Current Lecture - Aquatics Current Lecture- Aquatics Hydrologic cycle - Sunlight drives the cycle - Ocean, glaciers, groundwater, organisms are reservoirs for water Oceans and seas- Pacific, Atlantic, Indian - big ocean basins - 71% of earth covered in ocean - 4 miles deep at max- Average depth is 4000 meters- Low surface area to volume ratio - they resist change in temperature - Reduced sunlight - Low productivity Neritic Zone - Area after the intertidal zone Epipelagic Zone - From sea surface to a depth of 200 meters - Zooplankton eat Phytoplankton, which reside in these zones Mesopelagic zone - 200 meters to 1000 meters deep Bathypelagic zone These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- 1000 meters to 4000 metersAbyssal zone - 4000 meters to 6000 meters - Benthic organisms - that live belowHadal zone - 6000 meters and below Marine snow- Organic material falling from the upper layers of the ocean Hydrothermal vent - Pumps up hot sea water that are rich in sulfur and iron compounds, allowing organisms to perform chemosynthesis at such depth 80% of sunlight gets absorbed within the first 10 meters - Below 60 meters is the aphotic zone where respiration exceeds photosynthesis- Above 60 meters to surface is the photic zone where photosynthesis exceeds respiration Warm water floats over cold, because cold water is more dense False Bottom - Assuming one has reached the bottom of the ocean at 1000 meters, which is just the migratory fish coming up from the depths to feed on zooplankton 6 times the amount of plastic than marine organisms in the ocean - nurdles is what plastic is made off 88 billion per year - plastic Gradients - Thermocline o Change in temperature - Pycnocline o Change in pressure - Salinity o Change in salinity o High evaporation areas have water that is more saline Oceanic circulation Clockwise gyres - flow of the ocean currentsNorthern current - flows from east to west- Florida current is the head waters of gulf stream, which is the western boundary current, that is fast Coral reefs - They are species rich ecosystem that harbor ¼ of all marine organisms, found in the tropics - Pan tropical and found in waters where the water temperature ranges around 19 degrees CelsiusKelp forests - Found in temperate zones - Found in cold water that ranges from 12 to 16 degrees CelsiusIntertidal zonation - Tidal fluctuation produces gradient of environment conditions- Foreshore and seashore meet Supertidal fringe - Exposed to least amount of sea water (splashes) and exposed most to atmosphere Upper intertidal zone - Organisms can tolerate most desiccation, tides can be high or low in this sectionMiddle intertidal zone - Least exposure to atmosphere, mostly under waterLower intertidal zone - Organism don’t tolerate desiccation Subtidal zone - Only exposed during a tsunami or hurricane, fully submerged Organisms are in the intertidal zone based on their ability to take on desiccation and degree of exposure High variability - Sun - Salinity - Nutrients - Wave energy - Atmospheric exposureAlong the oceans there are semidiurnal tides, which means there is 1 high tide and 1 low tide a day, caused by the moon, sun, and wind Spring tides have the highest high tides and highest low tides Solar bulge offsets lunar bulge, you get neap tides, you get a high low tide and a low high tide Tidal cycle advances by a 50 minute cycle Estuaries - Mix of fresh and saltwater - Forms salt marsh channels - Variable currents - Lots of oxygen - High light at low tide - Nutrient rich - Lots of micro niches - High funal diversity - Not many