Why is it important that nutrients cycle? Agenda for Tuesday Jan 17th Cycles notes

Cycles in Earth Law of Conservation of Mass Biogeochemical cycles – exchange of matter through biosphere Reservoirs/sinks – places where matter & nutrients stored

Water Cycle Evaporation – liquid water becomes a gas Transpiration – evaporating off plants Condensation – water changing from gas to liquid

3. Precipitation – water falling to Earth from atmosphere 4. Run-off – water running over the land collect in the oceans, lakes or rivers 5. Infiltration – water seeping into the ground Ground Water- stored in underground caverns and porous rock Provides water for the soil, streams, rivers, and oceans

Human impacts on water cycle Removing forests and vegetation – increases runoff and erosion, reduces transpiration and lowers water tables Damming rivers increases evaporation and infiltration Emitting pollutants = acid precipitation Most threatening : overdrawing groundwater Agriculture, watering, etc. Lake Mead White Bear Lake http://www.wblcd.org/wl/images/articles/PDF/Million_dollar_question_meansWBP102616.pdf http://www.wblcd.org/wl/images/articles/PDF/TheupsanddownsofWBL_ST052216.pdf 7 7

What is transpiration? Agenda for Wednesday Jan 18th Carbon cycle Human affects of carbon cycle activity

Carbon and Oxygen Cycles

Where is the carbon? Stored in oceans, plants, air Fossil fuels Many animals pull carbon from water to use in shells, etc. Oceans contain earth’s largest store of carbon Photosynthesis – plants Fossil fuels Oil, coal, natural gas

Ways carbon moves Photosynthesis – moves from environment to plants 6 CO2 + 6 H2O C6H1206 + 6 O2 Respiration- moves from living things back to the environment Decomposition/Decay- moving from dead organisms back to the environment Combustion- Burning releases carbon back into the atmosphere Sunlight

Carbon Movement Photosynthesis

Carbon in the Atmosphere Greenhouse effect Trapping of heat by molecules (water, methane, CO2,)

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

Human Impact Fossil fuels Releases stores of carbon Burning anything releases more carbon into atmosphere Deforestation and Habitat Destruction Fewer plants mean less CO2 removed from atmosphere Methane release Agriculture and animal, wetlands, leakages during natural gas extraction, transportation, use

Humans affect the carbon cycle Today’s atmospheric carbon dioxide reservoir is the largest in the past 800,000 years

Photo from IPCC

The Keeling Curve

Effects of Climate Change Ecosystem change Ranges being shifted Some butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas Flowering earlier Loss of species Polar Bears, penguins, golden toad Climate Change: marine ecosystems

Why artic sea ice matters It reflects sunlight Glaciers are melting Why artic sea ice matters It reflects sunlight It influences ocean and air currents Keeps methane locked away It limits severe weather It supports native people and wildlife IPCC (2007) 21

Other Effects Sea Level Rise Spread of diseases Melting of ice sheets Expansion of heated (warm) sea water Flooding of coastal communities Spread of diseases Increase of extreme weather events Precipitation (rain and snowfall) has increased across the globe, on average http://news.nationalgeographic.com/2015/12/151229-before-after-earth-features/

Nitrogen Cycle Nitrogen is found in atmosphere and is unusable Nitrogen is used for proteins, DNA Nitrogen is found in atmosphere and is unusable Converted to a useable form through nitrogen fixation Special organisms/bacteria that convert legumes Lightning Animals get nitrogen from eating plants Returned to soil when animals urinates/dies Denitrification – nitrogen is converted back to gas

Humans affect the nitrogen cycle Fertilizer animal waste Excess Nitrogen can cause Eutrophication causes aquatic life to die due to low levels of oxygen

Decreasing Nitrogen Pollution Decrease fertilizer use Using new farming methods MN Buffer law Maintaining wetlands