2. A. How Land is Used
1. Land is a natural resource used by man.
2. Used for agriculture, logging, garbage disposal, urban
development, and as a fuel source.
a. These activities often impact Earth’s land resources.
B. How Agriculture affects our environment
1. How much land can be used for agriculture?
a. About 16 million square kilometers of Earth’s total land surface is
used as farmland.
b. The Earth has about 145 million square kilometers of land.
c. Only about 11% is used for food.
3. B. How Does Agriculture Affect Our Environment?
2. Feeding the growing population.
a. Farmers use higher yielding seeds and chemical fertilizers.
b. These methods help increase the amount of food grown on each
square kilometer.
c. The use of these chemicals can contaminate the soil and local drinking
water.
3. The use of Herbicides and Pesticides.
a. These chemicals help reduce weeds, insects, and other pests that can
damage the crops.
b. The use of these chemicals can damage the crops and the water table.
4. B. How Does Agriculture
Affect Our
Environment?
4. Organic Farming
a. Use of natural fertilizers,
crop rotation, and biological
pest control methods.
b. Help farmers grow crops
without using chemicals.
c. Unfortunately this type of
farming CANNOT currently
produce enough food to
feed all of Earth’s people.
5. B. How Does Agriculture Affect Our Environment?
5. Removing Vegetation for Crops
a. Exposes soil to wind, water, and gravitational erosion forces.
b. In some areas it can take up to 1000 years for topsoil to be
replaced.
6. C. How Can We
Reduce Erosion?
1. No-Till Farming,
Cover Cropping, and
Strip Cropping.
2. Terracing, Retaining
Walls, Planting
Vegetation.
3. Windbreaks and
Shelter Beds.
a. All of these are a
review!!
7. D. Does the Land Affect Livestock?
1. Land used for feeding livestock.
a. Livestock used as source of food for humans.
2. Farmers use corn and hay as livestock crops.
a. Used to feed their cattle/livestock.
b. These crops provide nutrients for cattle and improve the
quality of the meat.
c. Stop notes here.
8. E. What are Forest
Resources?
1. Resources found in
forests for medicine,
fuel, and other
materials.
2. ¼ of land on earth is
covered with forests.
3. 55% in developing
countries; 45% in
developed countries.
9. F. What is Deforestation?
1. Deforestation is the clearing of forests for
agriculture, grazing, development, or logging.
2. Amount of forested land in the world decreased by
0.24% (94,000 km2) each year between 1990 and
2000.
a. Most of this deforestation has occurred in tropical climates.
10. G. Why the Concerns about Deforestation?
1. Tropical rain forests contain diverse populations of
plants and animals that don’t live in other places.
2. Many of these plants might be important for
developing new medicines.
3. Some worry that removing too much of these forests
could lead to the extinction of some animals.
4. Cutting too many trees down could have a regional
affect on climate.
a. Water from tree leaves evaporates into the atmosphere where it
can condense to form rain.
b. If too many trees are cut down, less water enters the atmosphere
and the region receives less rainfall.
11. H. How Does Development of Land Change Our World?
1. From 1990 to 2000 the amount of urban roadways in the
United States increased by more than 13%
2. Paving land prevents water from soaking into the soil.
a. Instead it runs off into sewers or streams.
b. This increases the STREAMS DISCHARGE.
3. Stream Discharge is the volume of water flowing past a
point per unit of time.
4. During heavy rainstorms in paved areas, rainwater flows
directly into streams, increasing stream discharge and the
risk of flooding.
12.
13.
14.
15. H. How Does Development of Land Change Our World?
5. Many communities use underground water supplies for
drinking.
6. Covering land with roads, sidewalks, and parking lots
reduces the amount of rainwater that soaks into the ground
to refill underground water supplies.
a. This increases the chance and rate of flooding.
16. H. How Does
Development of Land
Change Our World?
6. Some businesses,
communities, and
private groups now
preserve areas rather
than pave them.
a. Preserving space
beautifies the
environment, increases
area into which water
can soak, and provides
space for recreation and
other outdoor activities.
b. See Figure 8
17. I. Sanitary Landfills
1. A waste-disposal area that is excavated and lined
with plastic, concrete, or clay; and filled with layers
of waste and dirt.
a. Because of this design, the landfill is able to prevent liquid
wastes from draining into ground water below.
2. About 60% of our garbage goes into Sanitary
Landfills
3. Since many materials do not decompose in
landfills, or they decompose slowly, landfills fill with
garbage and new ones must be built.
a. Type of soil, depth of groundwater, and neighborhood concerns
must be considered when choosing an acceptable location for a
landfill.
18.
19. A. Hazardous Wastes
1. Wastes that are poisonous, cause cancer, or that can
catch fire.
2. Previously, everyone-Industries and individuals-put
hazardous wastes into landfills along with household
garbage.
a. EPA passed laws banning hazardous wastes into sanitary
landfills.
20. B. How are some Household Wastes Hazardous?
1. Unlike Industries, individuals discard hazardous
wastes in the trash.
a. Insect Sprays, batteries, drain cleaners, bleaches,
medicines etc.
b. This garbage remains unchanged for many years and
pollutes the land and water.
2. Hazardous wastes can also cause cancer and other
disorders.
a. Affects humans and animals that interact with the land.
21. C. What is Phytoremediation?
1. Hazardous substances can contaminate the soil.
a. These contaminants may come from nearby
industries or leaking landfills,
b. Water filters into the ground and leaves toxic
substances in the soil.
2. Some plants can help fix this problem in a
method called PHYTO-REMEDIATION.
a. Phyto- means plant
b. Remediation- means to fix or remedy a problem.
22. C. What is Phytoremediation?
3. During phytoremediation, roots of certain plants
such as alfalfa, grasses, and pine trees can
absorb metals, including copper, lead and zinc
from contaminated soil just as they absorb other
nutrients.
23. C. What is Phytoremediation?
4. What happens to these plants after they absorb
metals?
a. If livestock were to eat the contaminated alfalfa, the
harmful metals could end up in your milk or meat.
b. Contaminated plants must be harvested and either
composted to recycle the metals or burned.
c. If the plants are destroyed by burning, the ash residue
contains the hazardous waste that was in the plant
tissue and must be disposed of at a hazardous waste
site.
25. D. How are organic pollutants broken down?
1. Living things also can clean up pollutants other
than metal.
a. Substances that contain carbon and other elements
like hydrogen, oxygen, and nitrogen are called organic
compounds.
i. Examples include gasoline, oil, and solvents.
26. D. How are organic pollutants broken down?.
2. Organic pollutants can be broken down into simpler,
harmless substances, some of which plants use for
growth.
a. Some plants release enzymes into the soil.
i. Enzymes are substances that make chemical reactions go
faster.
b. Enzymes from plant roots increase the rate at which
organic pollutants are broken down into simpler substances
used by plants for growth.
27. E. Natural Preserves
1. Not all land is used to
produce materials or
for storing wastes.
2. Some land remains
mostly uninhabited by
people.
3. National Forestlands,
Grasslands, and
National Parks in the
United States are
protected from many
problems stated in this
chapter.
a. Many other countries
also have Nature
Preserves.
