Biogeochemical Cycles. Nutrient cycling at its finest!

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1 Biogeochemical Cycles Nutrient cycling at its finest!

2 Four Criteria for Sustainability Sustainable Ecosystems Need: Reliance on Solar Energy High Biodiversity Population Control Nutrient Cycling This note set aligns with this concept.

3 What is a Biogeochemical Cycle? Bio - = life / living Geo - = Earth Chemical = chemical These are cycles in which elements or chemicals move through biotic (living) and abiotic (nonliving) parts of an ecosystem

4 Examples of Biogeochemical Cycles Carbon cycle Nitrogen cycle Phosphorus cycle Oxygen cycle Water cycle Sulfur cycle Rock cycle Mercury cycle

5 What Are Reservoirs/Sinks? A reservoir/sink is a place where the chemical of a cycle may be stored. There are 3 general places that chemicals in biogeochemical cycles are stored: Atmosphere the air Hydrosphere the water Lithosphere the land

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7 Carbon Cycle Processes Label the processes on your carbon cycle diagram. The 6 processes are: Photosynthesis Decomposition Cellular Respiration Combustion Sedimentation Diffusion

8 #1 = DIFFUSION #4 = PHOTOSYNTHESIS #2 = SEDIMENTATION #5 = CELLULAR RESPIRATION or #3 = DECOMPOSITION or DECOMPOSITION CELLULAR RESPIRATION #6 = COMBUSTION

9 Prompt Make the definitions in this form: When carbon in the form of and found in is converted into the form of and found in.

10 Carbon Cycle Processes Photosynthesis = when CO 2 from air is converted into food/sugar found in biomass of autotrophs (plants/algae) Decomposition = when decay of organic carbon biomass by decomposers releases carbon gases (like CO 2 ) into air Cellular Respiration = when CO 2 is released into air from breakdown of food/sugar Combustion = when carbon gases (like CO 2 ) is released into air after burning materials with organic carbon compounds Sedimentation = when carbon based materials are buried and combined with other elements to create sedimentary rock Diffusion = when CO 2 from air dissolves into water as CO 2 and vice versa

11 Forms That Carbon Comes In CO 2 = Carbon Dioxide - found in air and water CO 3 2- = Carbonate found in water & shells of aquatic organisms HCO 3 - = Bicarbonate -- found in water & shells of aquatic organisms H 2 CO 3 = Carbonic Acid found in water when CO 2 mixes with H 2 O Organically Bound Carbon in Biomass Much of biomass is made of or uses food/sugar. Most commonly used sugar in food use and production is glucose = C 6 H 12 O 6 Sediments/Rock - Limestone is made of fossilized shelled creatures Fossil Fuels coal and oil are made from fossilized plant and animal remains

12 Terrestrial Carbon Reservoirs/Sinks Carbon can be stored in: Plant Biomass Sedimentary Rocks (Limestone!) Fossil Fuels Soil Organic Matter Wetlands

13 #1 = DIFFUSION #4 = PHOTOSYNTHESIS #2 = SEDIMENTATION #5 = CELLULAR RESPIRATION or #3 = DECOMPOSITION or DECOMPOSITION CELLULAR RESPIRATION #6 = COMBUSTION

14 Aquatic Carbon Reservoirs/Sinks Carbon can be stored in: Aquatic Producer Biomass Coral Marine Organisms Shells/Skeletons Water Sedimentary Rocks (Limestone!)

15 Human Influences On The Carbon Cycle Increased Air Temperatures (Global Warming) Burning fossil fuel = more CO 2 in air Cutting/burning forests = less plants This means less photosynthesis = more CO 2 in air CO 2 traps heat; temperatures go up

16 Human Influences On The Carbon Cycle Ocean Acidification More CO 2 is in air so more is diffusing into ocean This makes more carbonic acid, lowering the ph Lower ph kills organisms and restricts shell formation in organisms (coral bleaching)

17 Organize the Nitrogen Cycle Place a form of nitrogen into each box/rectangle in the diagram. Use the information given about each form to select where each form could go. Use each form once, except for N 2, which is used twice!

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19 N 2 N 2 N 2 O Organically bound Nitrogen NO 2 NO 3 NH 4 Wastes with Organic Nitrogen

20 Forms of Nitrogen (Full Names) NH + 4 Ammonium NO - 3 Nitrate N 2 Nitrogen gas NO - 2 Nitrite N 2 O Nitrous Oxide

21 Keep Organizing the Nitrogen Cycle! There are 5 nitrogen cycle processes. Label each one on your diagram from the definitions that are given to you. Then jot down the definitions for your records!

22 N 2 N 2 N 2 O Organically bound Nitrogen NO 2 NO 3 NH 4 Wastes with Organic Nitrogen

23 Nitrogen Cycle Processes AMMONIFICATION conversion of nitrogen from waste materials into ammonium ASSIMILATION uptake of usable nitrogen forms into nitrogen-containing molecules in organisms (protein, DNA) DENITRIFICATION conversion of nitrate into gaseous forms of nitrogen NITRIFICATION conversion of usable ammonium into nitrite and then to usable nitrate NITROGEN FIXATION conversion on inert nitrogen gas into usable ammonium

24 N 2 N 2 N 2 O NITROGEN FIXATION Organically bound Nitrogen ASSIMILATION NO 2 NO 3 DENITRIFICATION NH 4 Wastes with Organic Nitrogen AMMONIFICATION

25 Facts on Nitrogen Cycle All chemical transformations in the nitrogen cycle are performed by bacteria. Legumes (type of plant) are well known to house nitrogen fixing bacteria. If farmers plant legumes, they will also have bacteria in the soil that perform nitrogen fixation. Types of legumes are: beans, peanuts, clover, alfalfa This helps reduce fertilizer use! Farmers who use manure for fertilizer are trying to promote ammonification to get more usable ammonium in the soil.

26 N 2 N 2 N 2 O NITROGEN FIXATION All parts of this cycle except for assimilation are performed by bacteria. Legumes are plants with nitrogenfixing bacteria. They live in nodules on the roots. Examples are soybeans, peanuts, clover, alfalfa. Farmers will rotate crops and grow legumes to naturally replenish soil nitrogen NH 4 Organically bound Nitrogen ASSIMILATION NO 2 NO 3 AMMONIFICATION Wastes with Organic Nitrogen DENITRIFICATION Farmers will lay down manure (organic wastes) to allow it to go through ammonification and replenish soil nitrogen

27 Human Alteration of Nitrogen Cycle The Haber Process Method to make inorganic (synthetic) fertilizer Chemically, N 2 is put through many high energy chemical reactions to make NH 3 or NH 4 Positives: More fertilizer We use the common nitrogen form of N 2 Negatives: Fossil fuels are used to make the high energy chemicals in the process. Fertilizer is a water pollutant. More fertilizer = more water pollution.

28 Phosphorus Cycle Forms of Phosphorus Phosphate ion (PO 4 3- ) Found in rock, water Organically bound phosphorus in living things What is phosphorus used for? Building block of DNA, RNA, ATP, cell membranes

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30 Phosphorus Cycle Reservoirs/Sinks of Phosphorus Organisms Lithosphere Hydrosphere How Can Humans Impact This Cycle? Phosphate can be mined from rocks to use in fertilizers. This means more phosphates get into water quicker, when fertilizers are used.