Natural Resources Overview

Natural Resources

• Natural resources are provided by Earth, including organisms, nutrients, rocks, water, and minerals
• They come from soil, air, water, or Earth's crust

Renewable Resources

• A renewable resource can be replaced quickly by nature
• Examples include fresh air, fresh surface water (lakes, rivers, streams), most groundwater, and fertile soil (if used properly)
• Sunlight is a renewable resource, expected to be available for at least 5 billion years

Non-Renewable Resources

• Non-renewable resources exist in a fixed amount in Earth's crust
• They are replaced only by geological, physical, and chemical processes over millions of years
• Examples include fossil fuels (crude oil, coal, natural methane), diamonds, other gemstones, gold, copper, and silver

Land

• Land provides living space for humans and other organisms, as well as space for growing crops, forests, grasslands, and wilderness areas
• Topsoil can be lost through erosion (wind or water)
• Plowing and lack of plant cover increase topsoil loss
• Topsoil loss makes soil less fertile and less able to hold water, impacting crop production

Desertification

• Desertification is the process of productive land becoming desert
• It occurs in hot, dry climates due to topsoil loss
• Factors include grazing animals in arid lands, and cutting down trees/shrubs for fuel
• Prevention includes reducing overgrazing and planting vegetation to anchor soil and retain water

Air

• A pollutant is a substance that negatively impacts living things or their activities by entering geochemical cycles
• Air pollution can be from natural or human sources, impacting both outdoor and indoor air quality
• Natural air pollutants include volcanoes (sulfur, causing acid rain and smog), fires, and radon

Water

• About 71% of Earth's surface is water
• Oceans regulate climate, provide habitats, and dilute pollutants
• Freshwater is important for agriculture, transportation, recreation, and numerous human activities
• Liquid water stores thermal energy without significant temperature increase, protecting aquatic life and regulating Earth's climate

Energy

• Human and organism energy mostly comes from the sun
• Fuels are materials used to produce energy
• Biomass is the total living matter in an ecosystem
• Biomass fuels come from living things, are renewable
• Ethanol is a liquid produced by fermenting crops, mixed with gasoline to reduce fossil fuel consumption
• It burns more cleanly than pure gasoline
• Biodiesel can be made from vegetable oils, animal fats, or recycled greases
• It's safe, biodegradable, and reduces air pollution

Fossil Fuels

• Fossil fuels are energy sources formed from compressed and incompletely decomposed plants and other organic matter (over millions of years)
• Examples include crude oil, coal, and natural methane
• Fossil fuels are non-renewable because formation takes a very long time and we use them faster than they are made

Alternative Energy

• The sun is the source of most Earth's energy
• Solar energy is free and does not pollute
• Hydroelectric power converts falling water's energy to electricity
• Nuclear fission involves a large nucleus splitting into smaller ones, releasing a large amount of energy