Weathering and Erosion Study Guide

Vocabulary

______à When chemical reactions dissolve or alter the minerals in rocks or change them into different

minerals

______à When rocks are broken apart by physical processes

______à Process in which surface materials are worn away and transported from one place to another by

agents such as gravity and water

______à Occurs when some materials are exposed to oxygen and water.

______à The removal of minerals that have been dissolved in water.

______à a mixture of weathered rock, decayed organic matter, mineral fragments, water, and air.

______à Method for reducing soil erosion; plant stalks are left in the field after harvesting and the next

year’s crop is planted within the stalks without plowing

______à Occurs in temperate and cold climates where water enters cracks in rocks and freezes.

______à All of the horizons of soil

______àDecayed organic matter that turns into a dark-colored material

______à Planting along the natural contours of the land to reduce soil erosion.

______à Method in which steep-sided, level topped areas are built onto the sides of steep hills and

mountains so that crops can be grown.

Write a P (physical change) or C (chemical change) next to each characteristic.

ü  Change in Color ______

ü  Change in energy ______

ü  Change in shape ______

ü  Change in odor ______

ü  Change in state ______

ü  Ability to dissolve ______

Write a M (mechanical weathering) or a C (chemical weathering) next to each example.

ü  Plant Roots ______

ü  Abrasion ______

ü  Oxygen ______

ü  Acid Rain______

ü  Release of Pressure ______

ü  Living Organisms ______

ü  Water ______

ü  Animal Actions ______

ü  Freezing and thawing ______

ü  Carbon Dioxide ______

Fill in the Blank

ü  The layer of soil that contains the most humus as well as smaller rock and mineral particles than the other horizons is the ______horizon.

ü  The organic material in humus includes ______.

ü  What is the main difference between mechanical and chemical weathering? (think-chemical composition) ______

______

ü  In order for oxidation to occur ______, ______, and ______need to be present.

ü  Litter is found in which horizon ______.

ü  What is the piling of sediment in a new area? ______.

Write A (A-horizon), B (B-horizon), or C (C-horizon) next to each picture and statement about soil horizons.

ü  Contains course sediments and parent material of soil ______

ü  Contains leached material from other layers ______

ü  Dark, fertile coil containing humus ______

ü  ______

ü  ______

ü  ______

Write W (weathering), E (erosion), D (deposition) next to each example

ü  Flood water pounding against a canyon wall and wearing it down ______

ü  Rain washing away soil from a hillside ______

ü  Layers of sediment forming at the bottom of the ocean ______

ü  A mudslide flowing down a steep hill ______

ü  Caves being formed by acid rain dissolving underground limestone ______

ü  Waves dropping sane on the beach ______

Name the five factors that affect soil erosion.

1.  ______

2.  ______

3.  ______

4.  ______

5.  ______

Explain the difference between soil in a desert and soil in a tropical rain forest (think about the pores of the soil).

______

______

______

Evaluate why soil erosion is a serious problem for agriculture

______

______

______