Ecology: Biogeochemical Cycles study of the interaction between abiotic and biotic components of……

Energy Energy passes through biological systems –Organisms transmit energy through food chains/webs –2 nd Law of Thermodynamics means that organisms that feed higher on the food chain have less energy available to them Therefore, as we move up food chain there is less and less energy and thus biomass

Movement of Matter Unlike photosynthetic organism which make their own chemical energy, non-photosynthetic organisms must use other energy transport mechanisms (e.g. conduction and convection) to gather matter. The food that they eat contains matter, but does matter move through food webs the same way that energy does? Answer: Yes and No We’ve discussed energy movement but we also must discuss matter movement. Matter is anything that has mass and occupies space. –The matter that we observe most commonly takes the form of compounds, polymers, alloys, or pure elements.

Matter to Matter Matter from one organism is moved and converted into matter in another organism in much the same was as we saw energy move in the food chain. Direction of Matter Flow If grass obtained it’s energy from the sun, where did it acquire it’s matter from?

Where is the matter? CO 2 H 2 0 C 6 H 12 O 6 O 2 Where does it come from? Atmosphere Light energy Carbon dioxide Water Photo- synthesis Glucose Oxygen gas

Where does atmosphere get CO 2 ? Respiration of living animal Respiration of plants But where did it come from? Well, a better question to ask may be, where did Carbon or Oxygen come from?

Sink Amount in Billions of Metric Tons Atmosphere 578 (as of 1700) (as of 1999) Soil Organic Matter1500 to 1600 Ocean38,000 to 40,000 Marine Sediments and Sedimentary Rocks 66,000,000 to 100,000,000 Terrestrial Plants540 to 610 Fossil Fuel Deposits4000 Estimated major stores of carbon on the Earth.

Energy and Elements within a biological system

Oxygen Cycle Largely tied to the carbon cycle

Consumers Producers Detritivores Nutrients available to producers Abiotic reservoir Geologic processes Generalized scheme for biogeochemical cycles

Other biologically important cycles Nitrogen Phosphorous Hydrogen Sulfur etc. These are the basic elemental building blocks of biological organisms (CHONPS)

Nitrogen Cycle Soil Nitrogen Consumers Plants Detritivores Clays, rocks, sediment Nitrogen fixing bacteria Denitrifying bacteria Atmospheric N 2

What you should be able to do: Trace the flow of energy and/or matter through food webs and biogeochemical cycles. Identify what happens to pools of matter when rates of change between pools change. Explain the effects (actual and potential) of man made changes in these rates. Identify and explain the biological, geological and chemical processes important to the Carbon and Nitrogen cycles.