Biogeochemical Cycles What is a biogeochemical cycle? What things cycle? (Which will you be responsible for?) What does NOT cycle? Chapter 13.5 in text

What is a biogeochemical cycle? Minerals (including the things you are made of) exist in set quantities on Earth, and are repeatedly recycled. The ones we will look at travel through food webs (bio), and have significant non- bio forms (geo). All your atoms have been parts of other organisms before you, many (many) times over. http://www.rps.psu.edu/probing/graphics/earth2.jpg

ALL of the atoms in living systems cycle. What things cycle? (Which will you be responsible for?) ALL of the atoms in living systems cycle. Some spend a lot of time out of the cycle (in a sink… reserve). We will look at water, carbon, nitrogen, and phosphorus, but there are cycles for potassium, vanadium, oxygen, sodium, chlorine, iron, calcium, hydrogen, etc….

water We will look at several images depicting this cycle: note condensation precipitation percolation runoff evaporation transpiration Do you know each of these? http://www.carillionplc.com/sustain/images/water-cycle.gif

evapotranspiration? sublimation? groundwater water (cont.) http://wetlab.coralhead.com/wp-content/uploads/2008/04/water_cycle.png

Equivalent depth (meters) water (cont.) How long does water sit around in the stages of the hydrologic cycle? (This is called its residence time.) also called aquifer→ Water Equivalent depth (meters) Residence Time Oceans/Seas 2500 ~4000 years Lakes/Reservoirs 0.25 ~10 years Swamps 0.007 ~1-10 years Rivers 0.003 ~2 weeks Soil moisture 0.13 ~2 weeks-1 year Groundwater 120 ~2 weeks-10000 years Ice caps/Glaciers 60 10-1000 years Atmospheric water 0.025 ~10 days Biospheric water 0.001 ~ 1 week http://www.spokaneaquifer.org/aq.htm Biospheric water? (The water in living things on Earth.) →

Water is not actually a mineral… it is a compound; water (cont.) note Water is not actually a mineral… it is a compound; but it is very important to living systems. Things live in water, as well as having water in them: freshwater, marine, and terrestrial ecosystems are all defined by water. The cycle includes three phases: gas, liquid, and solid Not much of this cycle is in living things! It enters via roots/drinking and leaves via evapotranspiration. What do the letters represent?→ http://www.bcscience.com/bc8/images/0_quiz_water_cycle.jpg

Carbon There is carbon in the air, in rock, in water, and you are made largely of it. note photosynthesis respiration combustion phytoplankton lithosphere Carbon reservoirs: Less CO2 dissolves as water temp rises… http://www.lbl.gov/Science-Articles/Archive/images2/sea-carbon-cycle.jpg

This shows the relative amounts of carbon in different places: carbon (cont.) This shows the relative amounts of carbon in different places: Most in sediments Lots of exchange with seas.

-Carbon enters the food chain through photosynthesis. carbon (cont.) -Carbon enters the food chain through photosynthesis. It leaves via respiration and decomposition. Increasing levels of CO2 add to global warming although the greenhouse effect itself is vital to life. zooplankton http://oceanworld.tamu.edu/students/forams/images/arctic_marine_food_web_90.jpg

Homework: Do research to find out - Carbon Footprint Homework: Do research to find out - - What is meant by carbon footprint? - What are the implications? i.e., why might we care? - Give some things that could be done individually to reduce your footprint. - What are some things you are doing well? ↓ Find an on-line resource to calculate yours. - Evaluate your confidence in said resource. - Cite your sources, making sure they are authoritative. This is the scoring rubric. http://www.earthday.org/footprint-calculator  site for carbon footprint calculator

nitrogen Nitrogen is in all proteins (amino acids) and nucleic acids (nitrogenous bases) nitrogen note Atmospheric N2 must be fixed, as by bacteria, to enter food chain… It then is assimilated through plant roots. Decomposers play a key role in re- cycling organic N. Bacteria also do denitrification (sending nitrogen back into the atmosphere). http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/earth_system/nitrogen_cycle_EPA.jpg

Artificial fertilizers upset the nitrogen balance… nitrogen (cont.) Lightning can also fix nitrogen Artificial fertilizers upset the nitrogen balance… http://www.h2ou.com/h2images/NitrogenCycle-lgr-F.jpg

Industry adds nitrogen compounds to air (contributing to acid rain) Agriculture adds excess N and P to waterways (eutrophication; kills lakes) nitrogen (cont.)

What do we need phosphorus for? Phosphorus cycle What do we need phosphorus for? It is part of every nucleotide in your body → www.geneticengineering.org/.../DNA.htm The energy for most of your body functions is carried in the last phosphate bond in adenosine triphosphate (ATP) ↑

uplifting weathering detritus detritivores Any obvious differences Phosphorus cycle the natural scheme uplifting weathering detritus detritivores Any obvious differences between this and the other cycles? (hint: look up) bioh.wikispaces.com/More+Elemental+Cycles?f=print

note: - no “volatile” form - “suspended particulates” Phosphorus cycle agriculture added note: - no “volatile” form - “suspended particulates” - loss due to harvest - this is also often a limiting nutrient: fertilizers applied leaching erosion big problems in rain forests nutrients.ifas.ufl.edu/.../Phosphoruscycle.htm

RECAP Matter is recycled through the ecosystem in biogeochemical cycles. - Water, carbon and nitrogen enter the food chain in different ways. - They spend different amounts of time in various reservoirs. All components of an ecosystem must remain in balance. However, energy…?

How are water and these 3 nutrients used in living systems? Which cycles have which phases: solid, liquid, gas? How does each enter the food web? How does each leave the food web? How are we dependant on other organisms in each cycle?

through biological systems impact you? Enduring Understandings All biological life is interconnected and [inter]dependent. Essential Questions How does the movement of matter and energy through biological systems impact you?

biogeochemical cycle residence time nitrogen food webs aquifer fixation sink biospheric assimilate water carbon denitrification condensation photosynthesis acid rain precipitation respiration eutrophication percolation combustion phosphorus runoff phytoplankton uplifting evaporation lithosphere weathering transpiration decomposition detritus evapotranspiration global warming detritivore sublimation greenhouse effect limiting nutrient groundwater zooplankton leaching hydrologic cycle carbon footprint erosion carbon cycle nitrogen cycle phosphorus cycle biogeochemical cycle carbon footprint limiting nutrients