Bell Work What are 4 reasons why it is important to recycle?

Intro – Lecture 32 (Yesterday’s Lecture number should have been 31 not 34) Ecological Threats

Threats to species Many different factors threaten the survival of species. These factors can lead to extinction.

Most Extinctions are From Human Related Behaviors Exploiting natural resources, such as the world's oceans, faster than they can be renewed Draining wetlands and clearing forests and grasslands for agriculture and towns and cities Ruining habitat by fragmenting it with roads and development Over-harvesting trees to make building supplies and paper products and for use as fuel Introducing harmful species into foreign ecosystems Releasing toxic pollutants Poaching, unsustainably hunting or illegally trading wildlife

Major Ecological Threats Overfishing Climate Change (Global Warming) Poaching, Illegal Trading Deforestation Loss of Habitat (Over-Population) Pollution

Overfishing Overfishing occurs when more fish are caught than the population can replace through natural reproduction. This wipes out a link in the food web.

Bicatch The incidental capture of non-target species such as dolphins, marine turtles and seabirds. Marine life of all types is hauled up with the catch, and then discarded overboard dead or dying.

Climate Change This problem is partly due to carbon pollution. Sea levels are rising and oceans are becoming warmer. Longer, more intense droughts threaten crops, wildlife and freshwater supplies. Thinning polar ice endangers polar bears Tropical amphibian diseases threaten rainforest

Illegal Wildlife Trade Unregulated hunting and trading, especially in biodiversity-rich countries, poses grave threats to both humans and animals.

Illegal Wildlife Trade Run by dangerous international networks, wildlife and animal parts are trafficked much like illegal drugs and arms. Examples: poaching of elephants for ivory, tigers for their skins and bones, marine turtles, and even timber trees.

Habitat Destruction Destruction or ecosystems can cut off migration routes and access to resources, leading to decline of species populations or even extinction.

Deforestation Many of the world’s most threatened and endangered animals live in forests. Deforestation comes in many forms, including fires, clear-cutting for agriculture, ranching and development, unsustainable logging for timber, and degradation due to climate change.

Forests play a role in climate change because they trap all the carbon dioxide and other greenhouse gases that would be released into the atmosphere and turn it into oxygen.

Pollution Pollution is the introduction of contaminants into the natural environment that cause adverse change

Pollution Examples Streams full of toxic chemicals from industrial processes Rivers overloaded with nutrients from farms Trash blowing away from landfills City skies covered in smog

Effects of Pollution Pollution may muddy landscapes, poison soils and waterways, or kill plants and animals. It can also cause and spread diseases.

Three Main Types of Pollution Land Pollution Air Pollution Water Pollution

Sources of Land Pollution Chemical and nuclear plants Industrial factories Oil refineries Human sewage Oil and antifreeze leaking from cars Mining Littering Overcrowded landfills Deforestation Construction debris

Facts About Land Pollution Every year one American produces over 3285 pounds of hazardous waste Land pollution causes us to lose 24 billion tons of top soil every year Americans generate 30 billion foam cups, 220 million tires and 1.8 billion disposable diapers every year We throw away enough trash every day to fill 63,000 garbage trucks Every day Americans throw away 1 million bushels of litter out their car window Over 80% of items in landfills can be recycled, but they’re not

Sources of Air Pollution Automobile emissions Tobacco smoke Combustion of coal Acid rain Noise pollution from cars and construction Power plants Manufacturing buildings Large ships Paint fumes Aerosol sprays Wildfires Nuclear weapons

Facts About Air Pollution Almost 232 million different types of vehicles are driven by U.S. citizens every day, adding greenhouse gases into the air U.S. vehicle emissions contribute 45% to global warming The average adult consumes 3,000 gallons of polluted air every day Vehicle exhaust contributes to 60% of carbon monoxide emissions in the U.S. and up to 95% in large cities Every year 335,000 Americans die of lung cancer, which is a direct result of air pollution

Sources of Water Pollution Factories Refineries Waste treatment facilities Mining Pesticides, herbicides and fertilizers Human sewage Oil spills Failing septic systems Soap from washing your car Oil and antifreeze leaking from cars Household chemicals Animal waste

Facts About Water Pollution Over two-thirds of U.S. estuaries and bays are severely degraded because of nitrogen and phosphorous pollution Every year almost 25% of U.S. beaches are closed at least once because of water pollution Over 73 different kinds of pesticides have been found in the groundwater that we eventually use to drink 1.2 trillion gallons of sewage, storm-water and industrial waste are discharged into U.S. waters every year 40% of U.S. rivers are too polluted for aquatic life to survive Americans use over 2.2 billion pounds of pesticides every year, which eventually washes into our rivers and lakes