Two natural forces are continuously at work on the landscape—the forces of destruction and the forces of construction. In locations of destruction, the material that is lost through natural events must go somewhere else, and landforms are constructed. When humans work the land, for agriculture, home building, and road construction, the landscape is changed to fit these purposes. Land use involves manipulating the landscape and its components—the soil, rocks, and vegetation. Humans change the land but differently than how nature changes it. In this section, students learn about habitats and the characteristic animals and plants of these habitats, they consider other important uses for land besides food production, and they conduct experiments with growing conditions and raise their own plants.