Resources and Conservation 4.3-4.4

The Water Planet 71% of Earth is water Oceans: Most saltwater Oceans: 1. Help regulate and moderate Earth’s climate 2. Vital part of the water cycle 3. habitat

The Water Planet Freshwater = needed in order for humans to live Less than 1% of water on Earth is useable fresh water Drinking, cooking, bathing, growing food

Water Pollution Two types of water pollution sources 1. Point source 2. Nonpoint source

Point Source Pollution Point source pollution = pollution that comes from a known and specific location Factory pipes Leaking landfill or storage tanks

Nonpoint source pollution Nonpoint source pollution = pollution that does not have a specific point of origin Runoff = water that flows over the land and does not seep into the ground Can carry nonpoint source pollution (ex: oil from streets) Pesticides from farms

What happens when water is polluted? Damage body’s organs Birth defects Infectious diseases Cancers Kill organisms and ecosystems

The Atmosphere Nitrogen, oxygen, water vapor, other gases Maintains life on Earth Oxygen essential for humans/animals Part of oxygen/carbon cycles During photosynthesis plants take in carbon dioxide from atmosphere and use it to make sugar During respiration, organisms return carbon dioxide to atmosphere

The Atmosphere Protects Earth from damaging solar radiation Ozone = protects Earth from 95% of UV radiation Some greenhouse gases (carbon dioxide, methane, and water vapor) help keep Earth warm

Air Pollution Burning of fossil fuels = major source of air pollution Vehicles, coal and oil-burning power plants Pollutants combine with water = acid precipitation

Air Pollution Burning of fossil fuels Creates carbon dioxide = greenhouse gas Amount has increased since industrialization Global warming = unnatural warming of the lower atmosphere Melting of glaciers --> rise in sea level and flooding

Air Pollution Chlorofluorocarbons (CFCs) = destroy ozone More of sun’s UV radiation would reach Earth’s surface Cataracts Skin cancers

Land Resources Provides soil and forests, mineral and energy resources Ex: lumber, petroleum, copper

Damage to Land Resources Mining = destroys Earth’s surface and vegetation Soil erosion Creates pollution --> contaminates soil and water

Damage to Land Resources Agriculture = farmers producing more food Pumping for irrigation = depleting groundwater Irrigation causes the build up of salts in soil (salinization) -->water evaporates--> salty crust --> can’t farm land anymore

Damage to Land Resources Clear-cutting = removal of all trees in an area of a forest Soil erosion Destroys ecosystems Disposal site = landfills, waste facilities Old landfills leak wastes that get into soil and undergound water

Protecting Our Resources Conservation = careful use of resources Pollution prevention = stopping pollution from entering the environment

Clean Water Act 1972 Industries required to reduce or eliminate point source pollution into surface waters Increase in sewage treatment plants 1990’s = 62% of US surface waters were safe for fishing and swimming

Safe Drinking Water Act 1974 Maximum contaminant levels of pollutants Public water resources cleaner today

Clean Air Act 1970 Established standards of 6 pollutants known to cause health problems Carbon monoxide, ozone, lead, sulfur dioxide, nitrogen oxides, particulates Low-sulfur coal, clean energy sources, hybrid cars, energy conservation

Protecting Land Resources Preventing pollution Managing land resources Soil conservation = contour plowing, strip cropping Selective cutting Less pesticide use Resource Conservation and Recovery Act = decreased illegal and unsafe dumping of hazardous waste