Download presentation
Presentation is loading. Please wait.
Published byKylie Morrow Modified over 10 years ago
2
Our Natural Resources, Then and Now
3
What is a natural resource? Any form of energy which can be used by humans. Those things that people come in contact with that may be used to perform any useful function. Objects, materials, creatures, or energy found in nature that can be put to use by humans.
4
Usefulness Changes A. Things that affect our definition of usefulness. –1. Religion- Hindu- cattle –2. Custom- Dogs as food source. –3. Technology and Science
5
Soil Resources A. Land area –1. U.S. 3,675,545 square miles or 2.26 billion acres –2. Surface ranges from 282 feet below sea level in Death Valley to 20,320 feet above sea level on Mt. McKinley
6
Soil Resources –3. Topsoil- uppermost layer of soil from which we get almost all of our food and natural fibers. –4. Today, almost 1/3 of our land area is not suited for farming; 8% covered by cities, factories, homes and highways; 60% is suited for food and fiber production of that only 17% can be used to grow crops.
7
Soil Resources B. Erosion –1. Since colonial times we have lost 1/3 of our topsoil to erosion. –2. Only 1/4 of our cropland is undamaged by erosion.
8
Soil Resources B. Erosion –1. Since colonial times we have lost 1/3 of our topsoil to erosion. –2. Only 1/4 of our cropland is undamaged by erosion.
9
Soil Resources C. Urban expansion –1. Land is converted to business or home usage. –2. Compaction results from concrete or other paving materials. –3. We must establish priorities for land use to balance food an d fiber production and industrial uses of our land.
10
Water Resources A. Useable Water –1. Earth is 70% water, how much is useable? –2. As a power source water was used to carry logs, float boats, turn water wheels
11
Water Resources –3. Everyday we use 300 billion gallons of water a. 60 billion depleted b. 240 billion return to the hydrologic cycle c. Much is damaged by heat and pollutants
12
Water Resources B. Controlling excess runoff –1. 37 states have average annual runoff of more than 10 inches 2. Much of the rain that falls, runs directly into the sea
13
Water Resources C. Major water problems –1. Control –2. Quality –3. Distribution
14
Fish and Wildlife Resources A. Non-domesticated animals, either game or nongame. –1. Considered renewal - only true while the species is alive and reproducing.
15
Fish and Wildlife Resources A. Since colonial times, 48 vertebrate species have become extinct in our nation. B. 130 regarded rare and endangered by 1970
16
Fish and Wildlife Resources 2. Assets –A. pleasure derived from wildlife –B. meat –C. insect destroying ability, valued at over one billion dollars per year. –D. hunting and fishing brings in more than one billion dollars each year.
17
Fish and Wildlife Resources 3. Wildlife conservation programs –A. programs directed especially for hunters and fishermen. –B. satisfying the demands of the non-hunting and non-fishing public through the use of parks and game preserves.
18
Forest Resources A. Acres of forest land –1. In 1607 half our land was forested, over 1 billion acres. Almost 70% is still forest –1/3 of todays forest land is noncommercial
19
Forest Resources B. Production –1. Since colonial times U.S. forests have produced about 2,700 billion board feet of timber. –2. Each year our forests grow more wood than we harvest.
20
Forest Resources C. Mature Forests –1. Canopy is dominated by mature, slow-growing trees a. produces very little wood
21
Other Resources A. Energy Sources –1. Most energy comes directly or indirectly from the sun –2. Wind- used to move our goods and pull water form the earth. A. Windmills Sailing Ships
22
Other Resources 3.Coal –A. Most widely distributed storehouse of the suns energy. –B. First discovered in America in 1673 in Illinois.
23
Coal –C. 35 billion tons have been produced in the US since mining began. –D. Estimate reserves of 2.5 trillion ton of US coal, but is a one time resource.
24
Other Resources 4. Oil –A. In late 1950s projected that oil reserves would last 14 years. –B. Today we use more oil but have greater store of known oil- is a one time resource.
25
Oil 5. Natural Gas –A. Clean, efficient –B. Proven reserves 260 trillion cubic feet.
26
Other Resources B. Minerals –1. Most widely used are the metals a. Fe, Cu, Al, Mg, Pb, Zn, Sn, (Iron, Copper, Aluminum, Magnesium, Lead, and Tin)
27
Other Resources C. Recreational Resources –1. Forests, lakes, beaches, mountains, parks, game animals and fish
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.