Environmental Concerns CH 6.4
Global Warming
Definition: Overall rise in Earth’s temperature Cause: Increase in CO 2 other greenhouse gases Effect: Melting of ice caps and glaciers & ocean acidification How do we manage: Decrease amount of CO2 in atmosphere from combustion
Acid Rain
Definition: Precipitation that carries acid back to Earth Cause: Nitrogen and Sulfur compounds mixed with H2O that originate from smokestacks and car exhaust Effect: Damages crops and forests, limestone/marble and increases acidity of ponds, lakes & rivers How do we manage: clean up combustion reactions and switch to alternative fuels
Eutrophication
Definition: the ecosystem response to the addition of artificial or natural substances Cause: High levels of Nitrogen and Phosphorus in water Effect: Dead zones in water (no available O2) due to overgrowth of phytoplankton How do we manage: Decrease the amount Nitrogen and Phosphorus runoff (fertilizer, sewage and detergents)
Biological Magnification
Definition: Pollutants become more concentrated up the food chain Cause: Toxins are fat/lipid soluble and NOT excreted Effect: Top predators near endangerment due to reproductive challenges How do we manage: decrease use of certain chemicals/pesticides
Deforestation
Definition: clear cutting of forests for agriculture, lumber, etc Cause: Human demand for lumber, space for agriculture or other goods Effect: More CO2 in atmosphere, less H2O in atmosphere, and habitat destruction How do we manage: timber responsibly, recylce paper products
Ozone Layer Depletion
Definition: loss of gas (O3 - ozone) that protects Earth from UV radiation Cause: CFC’s from aerosols & refrigerants deplete O3 from atmosphere Effect: increase in skin cancer & cataracts; harm crops and producers. increase in UV increases DNA mutations How do we manage: decrease use of CFCs and responsible disposal products containing CFCs
Overexploitation
caution!!! next slide is a bit graphic!!
Overexploitation - bushmeat
Overexploitation Definition: harvesting or hunting a population too intensely Cause: commercial overfishing & hunting (bushmeat) Effect: extinction, serious alteration of food webs, and lack of biodiversity How do we manage: responsible harvesting of oceans, manage hunting, aquaculture, helping impoverished nations such that bushmeat is not an option
Why is it important to conserve biodiversity? - Species are highly interconnected - Rely on others for resources & materials (medicines) - Genetic diversity for evolution - All agriculture depends fundamentally on Biodiversity, as do marine and freshwater food resources. - (humans rely on agriculture….just a bit)
Why is it important to conserve biodiversity? - Ecosystems (no need to write all of this down) - regulate climatic processes - breakdown wastes and recycle nutrients - filter and purify water - buffer against flooding - maintain soil fertility, purify air, and provide natural resources such as wood, textiles, and of course food. All agriculture depends fundamentally on Biodiversity, as do marine and freshwater food resources.
What is sustainable development and how does it protect ecosystems? - economic development that is conducted without depletion of natural resources. - Developing natural resources so that they can renew themselves and be available in the future - protects biodiversity - ultimately protects humanity