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Soil
APES
Question | Answer |
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Define Soil | relatively thin surface layer of the Earth's crust consisting of mineral and organic matter that is affected by agents such as weather, wind, water, and organisms |
What are the 4 types of soil? | mineral particles (45% of "typical" soil), organic matter ( about 5%), water (about 25%), and air (about 25%) |
List some reasons why soil is important to the environment. | 1. organisms, mainly microorganisms, inhabit the soil and depend on it for shelter, food and water 2. plants anchor themselves into the soil, and get their nutrients & water. terrestrial plants couldn't survive w/out soil, so humans couldn't exist either |
How is the parent material of soil formed? | it is a rock that has slowly broken down into smaller particles by biological, chemical, and physical weathering. |
Example of physical weathering | erosion (wind, water, ice, etc.) |
Example of chemical weathering | a plants roots or animal cells undergo cell respiration and the CO2 produced diffuses into soil, reacts with H2O and forms carbonic acid (H2CO3). This eats parts of the rock away |
What is Texture | the percentages (by weight) of different sized particles of sand, silt, and clay that it contains. |
What is Structure | how soil particles are organized and clumped together (sand, silt, clay) |
What is Friability | how easily the soil can be crumbled. |
What is Porosity | a measure of the volume of soil and the average distances between the spaces |