Students have read about the physical geography of North Africa, Southwest Asia, and Central Asia. In this lesson students will learn about desertification, a problem common to the region, and what steps are being taken to resolve this issue.
Students will use information from the Combating Desertification: The Israel Experience Web site to learn about the impact of desertification on the physical geography of the region. They can read how human activity increases the desertification of dryland ecosystems and how people are attempting to reverse and prevent the process. Students will answer four questions and then use what they have learned to create a pamphlet promoting sustainable dryland development methods that can work to prevent desertification.
- Students will understand the desertification process and its impact on the physical geography of the region.
- Students will use what they have learned to create a pamphlet promoting and explaining sustainable dryland development methods.
Applied Content Standards
Standard 7: The geographically informed person knows and understands the physical processes that shape the patterns of Earth's surface.
Standard 8: The geographically informed person knows and understands the characteristics and spatial distribution of ecosystems on Earth's surface.
Standard 14: The geographically informed person knows and understands how human actions modify the physical environment.
Standard 16: The geographically informed person knows and understands the changes that occur in the meaning, use, distribution, and importance of resources.
Student Web Activity Answers
- Desertification is the drying up of previously fertile lands. It is primarily caused by human mismanagement, which is linked to the enormous growth of the world's population and resulting overuse of the fragile resources of dryland ecosystems. Large herds overgraze. Farmers overcultivate and overirrigate. Areas are stripped of trees and shrubs in the quest for fuel and fodder. As more trees are cut down to clear more land for cultivating crops to feed more people, ever widening bands of barrenness are created.
- Dryland ecosystems cover about 47 percent of Earth's land surface. The four types are: 1) hyper-arid lands—7 percent of Earth's landmass; barely productive lands that provide a meager existence to small, usually nomadic, populations; water sources are oases and wells; 2) arid lands—about 12 percent of Earth's landmass, some precipitation, marginally productive, produce enough growth to feed livestock of nomadic pastoralists; 3) semi-arid lands—17.7 percent of Earth's landmass, can sustain pastoralists and subsistence agriculture without irrigation; 4) dry-subhumid areas—10 percent of Earth's landmass, can support a limited amount of rainfed cropland in valleys and plateaus, and pastoralism on hillsides and slopes.
- Human-made savannas on previously barren slopes prevent soil erosion, promote biodiversity, and restore limited productivity. Grasslands sprout around the widely spaced trees, providing pleasant scenery and limited grazing land.
- Allocation of freshwater in Israel is strictly regulated. The development of drip irrigation revolutionized dryland agriculture in the 1970s. New water sources include brackish and geothermal fossil water, recycled waste water, and harvested run-off water.
- Pamphlets should discuss the development of aquaculture, solar energy, tourism, value-added industries, biosphere reserves, and afforestation.
Go To Student Web Activity