2 25 14 Oceans 9 5 of all water on earth is saltwater Salt input comes from land runoff Salt levels are maintained overtime o Salt removal Pore water Binding minerals o Plate tectonics recycle land to reproduce salt Distribution of Marine Life Ocean life is not evenly distributed Most ocean is like a watery desert Most of life in the ocean is found near the continents o Above continental shelf Life Above Continental Shelf Nutrients are limiting factor o Stirred up from the bottom by currents and storm o Richest area of life are in the temperate climates Life strongly fluctuates with the seasons o Nutrient availability stimulates entire food web The Phonic Zone Where light first enters the water o Where all photosynthetic organisms live Sun goes down 100 meters Take into account clarity of the water 90 of all ocean life is found here o High productivity It is the area where light penetrates through water Extends 100 200 meter below the surface o Depending on water clarity Marine Plant Adaptions Plants must be able to float to remain with in the photonic zone to photosynthesize Most are unicellular and microscopic o Small size facilitates transfer of nutrients into wastes out of cell Temperature Adaptions Fish o Cold blooded same temperature as surrounding areas Don t require as much oxygen or food as warm blooded animals Mammals o Warm blooded Generate internal body heat o Insulates bodies with blubber Fat and connective tissue o Arctic bowhead whale has blubber layers 2 feet thick Dealing with Salt Water Sea water is saltier than animal body fluids o It pulls water from body tissues Osmosis Movement of water molecules through a semipermeable membrane from higher to lower concentrations Marine Vs Freshwater Fish Marine fish regulate salt because body fluids are less salty than the water o They drink salt water excrete salt water and have low urine production Freshwater fish their body fluids are more salty than the water and have high urine production Salt Water Adaptations Fish Sea birds through nose Whales mammals o Drink sea water eliminate salt through gills o Drink salt water remove salt with salt glands and sneeze out salt o Don t drink salt water o Blubber forms barrier to osmosis o Get both salt and water from organisms they eat Acquiring oxygen Oxygen dissolved in sea water is 50X less than that in air Marine animals need oxygen to survive Fish have gills that work by countercurrent exchange o An exchange between 2 flows going in opposite directions Marine Mammal Oxygen Adaptation Use oxygen more efficiently o Exchange 90 of the air in each breath and their blood chemistry high red blood cell counts allows greater oxygen retention Have a high tolerance to lactic acid and carbon dioxide o Their muscles can work anaerobically without oxygen while they hold their breath Can tolerate tremendous atmospheric pressure at great depths o Lungs and ribs are collapsible minimizing air spaces Adaptation to Water Pressure Pressure increases rapidly with depth Adaptations o Most marine organisms lack large compressible air pockets inside their bodies o Water filled bodies exert the same amount of pressure Too much of a good thing Dead Zones A high influx of nutrients from land use agriculture is called Eutrophication o Started around the 1970 s in 2008 there were over 400 of them 2 27 14 Life on Plastic Earth What are plastics made from How much new plastic does each person on earth use How much plastic is recycled in the US Where does most of the plastic remain and for how long 7 Landfills Gyre floats below surface Video Ocean Acidification How does it happen What are the consequences for Why is it difficult to clean out the plastic from the pacific Plastic gets stuck in the current and they convert and create a vortex pacific Clams and marine food web Shells and skeletons are getting weaker They molecules are making the ocean more acidic Shells could dissolve Coral reefs ocean species live in coral reefs Humans we would not get nutrients from seafood if there s none left Transpiration plants get water from the ground and bring it to top of the leaves and then aspire Condensation change from gas to liquid phase creating water vapor that condenses Transports to the clouds and creates Precipitation Creating Snowmelt Runoff off mountains and onto the Surface Runoff Then Infiltration goes into Groundwater where Groundwater Flow goes into Plant Uptake Water Distribution on Earth 95 of Earth s water is salt water 2 of fresh water is ice Most of the rest of fresh water is underground 007 of water is found in rivers lakes etc Rivers and Streams Abiotic factors Water flow Light community Oxygen o Constantly moving water sweeps nutrients through the system o Affects the amount of algae that can grow which affects the rest of the o Diffuses in through the water surface o Solubility in water decreases as temp increases o Cool fast moving streams are high in oxygen o Can be limiting if there is a large amount of animal respiration Water follows a predictable pattern as it moves from headwater streams to Gradual changes in the biological community as energy sources and physical The River Continuum large rivers conditions change Nutrient Spiraling 1 Nutrient is dissolved into water 2 Nutrient is taken up by living organisms 3 Organism dies nutrient is released back into water during decomposition River Continuum Stages Headwaters Forested small streams Primary nutrient input is forest leaves have different nutrients Leaf shredders and collectors o Shredders shred and eat leaves o Collectors Filter particles from water Mid reaches Predator abundance remains the same but prey mixture changes Larger stream less trees algae grows Collectors grazers predators o Grazers eat algae Lower Reaches Much less algae due to river sediment Primary nutrient input is organic with carbon in it particles Collectors and predators River continuum ecology moving on Any time organic material is added it is used or stored with a small portion o Resources are constantly moving downstream Constantly moving resources stimulate the system to stay at equilibrium o Because there is never a huge influx of nutrients communities have a uniform use of every available resource so disturbances and fluctuations are usually corrected very quickly DAMS Human Impact Changes natural cycles o Seasonal flooding Vegetation and aquatic organisms depend on this Dam floods scour downstream land Eliminate habitat o Changes the river food web