1) Explain three ways that people use and change land. forests are cleared, wetlands drained, and deserts irrigated to create farmland. People mine resources from within the ground. development also changes the land.

2) Describe the structure of fertile soil. Soil has four layers: litter- leaves and grass Topsoil- rocks, air, water, decaying animals and plants, and roots. subsoil- rocks, air, water, less decaying animals and plants Bedrock- erosion processes

3) Why is soil so important to human beings? soil is vital to human beings, because most life on earth could not exist without it. soil contains the minerals and nutrients that plants need to grow. it also absorbs, stores, and filters water.

4) How do erosion, nutrient depletion, and desertification damage or destroy soil? erosion: Water, wind, or ice sweep soil away. nutrient depletion: soil is robbed of nutrients if the same crops are planted every year. desertification: Plants die, soil blows away, and the area becomes a desert

5) What are the effects of deforestation and urbanization? soil becomes less fertile; flooding and erosion increase; wildlife population decreases; water and air pollution increase; less land is available for farming.

6) _____________ Deforestation is the process of people moving to city areas. False: Urbanization is the process of people moving to city areas

7) _____________ Because it can take one year to form just a few centimeters of new soil, it is important to protect Earth’s soil. False: hundreds of years

8) _____________ If a farmer plants a field with different crops each year, the soil becomes less fertile, a situation called nutrient depletion. False: the same crop

9) _____________ Without soil, most life on land could not exist. True

11. Strip mining exposes soil and causes _____________ 10) The structure of fertile soil contains layers including litter, topsoil, _____________, and bedrock. Subsoil   11. Strip mining exposes soil and causes _____________ 12. When soil becomes depleted, farmers usually apply fertilizers, which include _____________ that help crops grow better. Erosion Nutrients

Drought Topsoil Land reclamation One cause of desertification is _____________, a period when less rain than normal falls in an area. _____________ is the layer of soil where the most water and nutrients are absorbed by plant roots. 15. The process of restoring an area of land to a more productive state is called _____________. Drought Topsoil Land reclamation

l Destruction of woodlands ___ litter: ___ deforestation: l Destruction of woodlands ___ litter: f Top layer of soil containing dead leaves and grass ___ topsoil: b. layer of soil in which water and nutrients are absorbed by plant roots b ___ subsoil: h. layer of soil above bedrock

22.___ nutrient depletion ___ bedrock: e.the rock that makes up Earth’s crust ___ erosion: j .the process by which water, wind, or ice moves soil or particles of rocks 22.___ nutrient depletion d. a process in which soil becomes less fertile 23.___ fertilizer a.material that includes nutrients that help crops grow better

24. ___ desertification i. the advance of desert-like conditions into areas that were fertile 25.___ drought c. a period when less rain than normal falls in an area 26.___ land reclamation g. restoring an area of land to a more productive state 27.___ urbanization k. the process of people moving to cities