QUICK! Why is it important to living organisms that nutrients cycle? A: Cycling makes nutrients available for other organisms to use.

Cycles Transforming energy into usable forms Biogeochemical cycle- exchange of matter through the biosphere. *Matter cannot be created or destroyed!!!* Cycling of nutrients in the biosphere involves: Matter in living organisms Physical processes found in the environment Transforming energy into usable forms

Water cycle Who remembers the water cycle from last year? What processes are involved?

Water Cycle Water is constantly evaporating into atmosphere (water vapor) Vapor rises, cools, forms clouds (condensation): 90% of water vapor evaporates from ocean, 10% from surface of plants (transpiration). Water falls from clouds in form of precipitation

Water cycle

Nitrogen Cycle *Nitrogen enters the food web when plants absorb nitrogen compounds from soil* Consumers get nitrogen by eating plants or animals that contain nitrogen. 6

Atmospheric nitrogen (N2) Nitrates (NO3) Nitrogen – needed to make proteins Conversion of nitrogen into a form that is useable by plants is called nitrogen fixation. -animals and plants cannot use nitrogen directly from the atmosphere -nitrogen gas captured by bacteria, convert into usable form THE GOAL! Atmospheric nitrogen (N2) Nitrates (NO3) 7

Nitrogen Cycle (cont.) Nitrogen is returned to the soil in several ways: 1. Animals urinate 2. Organisms die (decomposers!) 3. Lightning Organisms convert ammonia into usable nitrogen compounds. (Nitrification) Fixed nitrogen converted back to gas and reenters atmosphere (Denitrification) In the soil

Nitrogen Fixation http://www.youtube.com/watch?v=4NKGS4bj7cc 9

The Carbon Cycle Carbon Contained within… Major part of organic molecules Carbohydrates, proteins, fats, and nucleic acids. Contained within… animal skeletons rocks the atmosphere (CO2) dissolved in oceans fossil fuels (coal, natural gas, oil)

Carbon Cycle http://blogs. dickinson

Human Impact Fossil fuels release carbon stores very slowly Burning anything releases more carbon into atmosphere — especially fossil fuels Increased carbon dioxide in atmosphere increases global warming Fewer plants mean less CO2 removed from atmosphere

https://www.youtube.com/watch?v=2D7hZpIYlCA

Phosphorous Cycle Phosphorous essential to organisms as it is part of molecules such as DNA and RNA. Remains mostly on land and in the ocean as inorganic phosphate- usually in rocks or soils. Rocks and sediments release phosphate as they wear down

* Plants bind phosphate into organic compounds when they absorb it from the soil or water. * Organic phosphates make their way through the food web to the rest of the ecosystem

Phosphorus Cycle