WARM UP What can make up a population? 1
ECOSYSTEMS: Cycles www.swpc.noaa.gov/ 2
Biochemical Cycling Cycling of nutrients called biogeochemical cycling Move nutrients from nonliving world to living organisms and back. Without recycling, life could not exist Four biogeochemical cycles Carbon Oxygen - Nitrogen - Phosphorus http://upload.wikimedia.org/wikipedia/commons/thumb/2/21/cno_cycle.svg/300px-cno_cycle.svg.png 3
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Carbon Cycling Photosynthesis removes carbon dioxide from the atmosphere and turns it into biomass. Respiration returns carbon dioxide to the atmosphere when food is burned by cells. Carbon is also returned to the environment when an organism dies through the action of detrivores. 5
Carbon Cycling Some organisms die and accumulate. Forms large layers of limestone rock Store carbon in rocks for millions years Known as carbon reservoir 6
Carbon Cycling Alternate path plants and animals are buried Exposed to heat and pressure beneath Earth s surface Causes chemical changes Produces fossil fuels oil and coal Oil once living plankton Coal remains of plants buried in swamps http://www.mii.org/minerals/minpics1/coalanthracite.jpg 7
Carbon Cycling Fossil fuels known as hydrocarbons Composed of hydrogen and carbon Burning returns to atmosphere as carbon dioxide http://www.ust.hk/~webpepa/pepa/ways_of_protection/air_general.jpg 8
Carbon Cycling Creation of methane gas (CH4) Mud of rice paddies in Asia Anaerobic bacteria release methane gas Cows produce methane in their digestive systems. http://www.palacesandtigers.com/images/gallery/sri_lanka/vil%20uyana%20rice%20paddy.jpg 9
Oxygen Cycling One of most important interactions Photosynthesis and respiration reactions Photosynthesis consumes carbon dioxide and releases oxygen Used during respiration and carbon dioxide is released Vital link between plants and animals on Earth www.rps.psu.edu 10
Oxygen Cycling The Earth s crust is also a reservoir for oxygen storage. http://lasp.colorado.edu/~bagenal/3720/class21/co2cycle.jpg 11
Nitrogen Cycling - Nitrification Begins with bacteria in soil and roots Combine ammonia with other atoms Nitrogen compounds absorbed by roots of plants Used to make proteins http://www.thisland.uiuc.edu/50ways/images/5b.jpg 12
Nitrogen Cycling - Nitrogen Fixation Legumes harbor bacteria that fix nitrogen in small nodules in their roots. Convert atmospheric nitrogen to plant-available nitrogen Nodules on Clover roots http://overton.tamu.edu/clover/cool/nodcrimw.jpg 13
Nitrogen Cycling - Denitrification Bacteria in the soil break down dead organisms, releasing nitrogen gas into the atmosphere. Denitrification filter, part of wastewater treatment plant. http://www.tampagov.net/dept_wastewater/information_resources/advanced_wastewater_treatment_plant/virtual_tour/images/denit_filter.jpg 14
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Phosphorus Cycling Major source of phosphorus is not the atmosphere Found in rocks Phosphate-containing rocks become weathered (break down) Main source of phosphorus for ecosystems of Earth http://content.answers.com/main/content/wp/en/thumb/b/b9/180px-phosphaterockusgov.jpg 16
Phosphorus Cycling Animal wastes contain large amounts of phosphorus Helps to recycle back through food chain Rare in some ecosystems Called a limiting factor http://www.gardening.cornell.edu/lawn/almanac/images/fertilizer3.gif 17
Phosphorus Cycling Human activity raises phosphorus levels Waste disposal and use of fertilizer Causes rapid growth in aquatic plants and algae Result is algae bloom Chokes waterway with overgrowth http://www.waterencyclopedia.com/images/wsci_01_img0017.jpg 18