Ecology

Cycles of matter

Eutrophic lakeHealthy lake (high primary productivity due to excessive nutrients) What is the Difference Between the Lakes?

What types of processes are occurring in each of these pictures? Which are natural? Which are man-made?

Biogeochemical Cycles “Bio”-Biology “Geo”-Geology “Chemical”-Chemistry Elements, chemical, compounds,& other forms of matter passed from one organism to another. – How is this different from energy flow?

Recycling in the Biosphere  Matter is recycled within & between ecosystems  Biological systems don’t use up matter, they transform it  Inhaling atoms that dinosaurs did!!!

The Hydrologic Cycle All living things require water to survive Where does water come from? -Moves between ocean, atmosphere, & land

Nutrient Cycle Nutrients- all chemical substances that an organism needs to sustain life Every organism needs nutrient to build tissues and carry out essential life functions AKA Carbon, Nitrogen, and Phosphorus cycles

Carbon Cycle Carbon is a key ingredient of living tissue CaCo 3 Animal skeletons also found in rocks CO 2 (Carbon dioxide) – Given off by plants & animals during respiration – Makes up atmosphere – Released into atmosphere by volcanic activity, burning fossil fuels and vegetation – Decomposition of organic matter – Taken in by plants in photosynthesis

4 main processes move Carbon through the cycle: 1. Biological- photosynthesis, respiration, decomposition 2. Geochemical – Erosion & volcanic activity 3. Mixed biogeochemical- burial & decomposition 4. Human Activities-mining, cutting & burning forest, burning fossil fuels

CO 2 in Atmosphere CO 2 in Ocean

Nitrogen cycle All organisms require Nitrogen to make amino acids (which are used to make proteins) N 2 makes up 78% of Earth’s atmosphere (USELESS) Humans add Nitrogen thru Nitrate (fertilizers) Found in waste – -Ammonia (NH 3 ), nitrate ions (NO 3 - ), & nitrite ions(NO 2 - )

More on Nitrogen Cycle Only certain types of bacteria can use nitrogen gas directly They are found in soil and on roots of plants called legumes (“magical fruit”) They convert it to ammonia through Nitrogen Fixation Other bacteria convert ammonia into nitrates & nitrites Producers use it to make proteins Consumers eat producers and reuse nitrogen to make proteins

DEATH!!! When organism die, decomposers return nitrogen to soil as ammonia Ammonia taken up by producers (again) Denitrification -other soil bacteria convert nitrates into nitrogen gas. Releases nitrogen into atmosphere.

Nitrogen Cycle N 2 in atmosphere NH 3 ammonia NO 3 - & NO 2 - Nitrate & nitrite

1.Organic wastes(from plants and animals) add nitrogen to the soil. 2.Bacteria in the soil convert the nitrogen into forms plants can use. 3.Plants use nitrogen in the soil to grow, develop, and produce seeds. 4.Plants are eaten by animals and people. The organic waste (which contains nitrogen) is returned to the soil again. Simplified Nitrogen Cycle

Phosphorus Cycle 1. Reservoir – erosion transfers phosphorus to water and soil; sediments and rocks that accumulate on ocean floors return to the surface as a result of uplifting by geological processes 2. Assimilation – plants absorb inorganic PO 4 3- (phosphate) from soils; animals obtain organic phosphorus when they plants and other animals 3. Release – plants and animals release phosphorus when they decompose; animals excrete phosphorus in their waste products (Phosphorus is required for the manufacture of ATP and all nucleic acids)

Nitrogen Cycle Game Assignment Write a paragraph about your trip through the Nitrogen cycle. Include information about (1) where they went, and (2) how they got to each destination. Bring to class completed tomorrow.

Post Questions How many stops can you make on your trip? Will your journey ever end? Was everyone’s journey the same? Why not? What would happen if excess amounts of fertilizers (high in Nitrogen and Phosphorus) were to leach into our water supply