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Energy pyramid Bioaccumulation/Biomagnification

• Definitions

Bioaccumulation/Biomagnification Biogeochemical cycles

• Water, nitrogen, carbon, phosphorous, etc…

• Involve geological (atmosphere, lithosphere, hydrosphere) and biological (trophic levels) components

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Nitrogen cycle Nitrogen cycle

Cycling in ecosystem- nitrogen and phosphorous

Biotic

Abiotic

Energy Heat/Motion

Uptake by producersMineralization (decomposition)

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Carbon Cycling in ecosystem: carbon

Biotic

Abiotic

Energy Heat/MotionBiotic

Abiotic

Heat/Motion

Uptake by producersRespiration

Water cycle Direct values

• Private goods or commodity values• Harvested

– Meat– Fuelwood/timber– Edible/medicinal plants

• Consumptive and productive use

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Overexploitation

• Direct commercial exploitation

Overexploitation

• Direct commercial exploitation• The environmental side effects of

collecting nonliving resources

Overexploitation

• Direct commercial exploitation• The environmental side effects of

collecting nonliving resources• Unintentional mortality of nontarget

organisms

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Overexploitation

• Direct commercial exploitation• The environmental side effects of

collecting nonliving resources• Unintentional mortality of nontarget

organisms• Overhunting

Overexploitation

• Direct commercial exploitation• The environmental side effects of

collecting nonliving resources• Unintentional mortality of nontarget

organisms• Overhunting• Global trade of wildlife

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~30,000

7-8 million

2-3 million

500-600 million• Birds: 2-5 million

9-10 million

Overexploitation

• Population size• Technology• Self imposed

restrictions • Typical pattern• Difficulty in regulation

• Remember MSY??

Indirect values

• Public goods, non-consumptive use value• Benefits from biodiversity not involving

harvesting or destroying– Ecosystem productivity– Water quality– Soil protection– Climate– Flood control– Waste treatment and nutrient retention

Example: River vegetation

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Ecosystem productivity

• Primary productivity-energy

• Terrestrial and aquatic

• Diversity-productivity relationship

Soil and water resources

• Buffering ecosystems– Flood – Drought– Water quality

• Logging, farming, development affect soil erosion– Useless for farming– Kill aquatic life– Water undrinkable– Loss of electrical output

Climate regulation

• Local: shade, water transpiration, windbreaks

• Regional: deforestation -> lower rainfall, lower uptake of CO2 (global warming)

Waste treatment/nutrient retention

• Aquatic communities (fungi and bacteria)

• Break down/immobilize pollutants (2.4 trill)

• Store sewage and nutrient runoff for photosynthetic organisms & nitrogen fixing

• New York Bight

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Species relationships

• Predation (bottom-up and top-down)

• Pollination• Microorganisms

Recreation and ecotourism

• Enjoyment!• Hiking, fishing, camping, rock climbing,

bird watching• Ecotourism- to experience unusual

communities