Environmental Issues The earth’s biodiversity (number of different species that live in an area) is facing a new crisis due to a dominant new animal – MAN!!

3 Main Threats to Biodiversity Habitat Loss – biggest threat!! Habitat Degradation – damage by pollution, acid precipitation, pesticide use, ozone depletion, etc. Habitat Fragmentation – separation of wilderness areas

What is the big deal about biodiversity? Life depends on life (food chains, webs) Many medicines yet to be discovered (improving health) Importance to humans (diet, drugs) Losing biodiversity means organisms may become threatened, endangered, or even worse….EXTINCT!

Acid Precipitation Cause – air pollution from the burning of fossil fuels releasing sulfur & nitrous oxides into atmosphere Effect- deterioration/degradation of forests and lakes- change soil chemistry-release toxic elements Solution – alternate sources of energy

LAND POLLUTION Cause – dumping refuse/solid waste on land Effect – habitat degradation (damage to habitat by pollution) Solution – Refuse, Replace, Reduce, Reuse, Recycle

Thinning of Ozone Cause – Chloroflourocarbons (CFC’s) – chemicals that break down the ozone layer (in refrigerants, aerosols) Effect – increased ultraviolet radiation, skin cancer, damage to crops, etc. Solution – quit using CFC’s!

GLOBAL WARMING Cause – cutting down trees and burning fossil fuels & releasing CO2 into the atmosphere Effect – Greenhouse effect – increased CO2 acts like a blanket, trapping heat, increase in global temp. – melting polar ice caps, flooding, increased droughts, etc.

WATER POLLUTION Cause – runoff from agriculture (fertilizer), oils spills, industrial waste (sewage), heat (thermal) , pathogens, etc. Effect – habitat degradation (due to pollution), disease transmission

OVERPOPULATION Cause – High birth rate, low death rate, improved technology, etc. Effect – Root cause of all of the other environmental issues! Solution – lower fertility rates, education of women, etc.

PESTICIDE USE Cause – spraying/applying pesticides on fields, in yard, etc. Effect – habitat degradation, affects the entire food web also…biological magnification!!! Solution – biological control!!! Ex. Use lady-bugs to control aphids

Conservation biology is a new field that studies methods and implements plans to protect biodiversity! Habitat preservation (nature preserves) Reintroduction programs/captivity (zoos) Legal protection of species (U.S. Endangered Species Act of 1973)