Soils Benchmark Review Packet

SOILS BENCHMARK ASSESSMENTStudent Review Packet

In the space below, answer questions 1 through 3.

1. What is loam?An agricultural soil that has an optimum combination of different soil particle sizes. It contains 40%

2. What is soil porosity?A measure of the volume of pores or spaces per volume soil and of the average distances between these spaces

3. How does the soil porosity relate to the size of the particles found in that soil?The larger the particles, the more space between them. The smaller the particles, the less space.

MISCDefine (look in the wetlands reading):

1. Anoxic:Without oxygen

2. Hydric:Filled with water

3. Buttressed:The base of the tree is widened for support because the soil is very wet.

Why would farmers apply lime to soils? (remember lime = calcium carbonate)For acidic soil, lime helps raise the pH so that the soil can support plant growth.

List the Macronutrients1. Nitrogen2. Phosphorus3. Potassium

List the Micronutrients: 1. Calcium2. Magnesium3. Sulfur

Use the Soil Texture Triangle below to answer Numbers 4 through 6.

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Soils Benchmark Review Packet

4. What would you classify a soil that is composed of 60% sand, 30% silt, and 10% clay? Sandy loam

5. What would you classify a soil that is composed of 20% sand, 10% silt, and 70% clay? Clay

6. What would be the particle composition of a soil that is classified as sandy clay? 50% sand, 40% clay and 10% silt

Label the following Soil Profile and use it to answer Numbers 7 through 9.

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Soils Benchmark Review Packet

7. Identify the layer(s) of soil in which each soil process occurs.

a. accumulation - Subsoil

b. decomposition - Organic layer

c. leaching - Topsoil

d. weathering - Weathered bedrock and bedrock

8. Identify the layer of soil in which you would expect to see the following soil colors

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Organic LayerTopsoil

Subsoil

Weathered Bedrock

Bedrock/Parent Rock

Soils Benchmark Review Packet

a. Dark brown to yellow - Topsoil

b. Determines the color of the soil - Bedrock

c. Black, dark brown - Organic layer

d. Brown, reddish to orange - Subsoil

9. Where in the soil would you find the highest concentration of plant roots? Why?Most of the roots would typically be found in the topsoil. The topsoil is the layer

that should have the most plant nutrients that the plant needs to grow and the composition of the layer should be loose enough for the roots to grow.

10. As you move down in the soil profile does the color darken or lighten? Why? This is due to leaching. When water moves down the soil layers, it carries minerals

from one layer to another. The soil that loses minerals becomes lighter and the soil that gains minerals becomes darker.

WeatheringList the methods of chemical and physical (mechanical) weathering

Chemical Oxidation Acid rain Acids from plants

Physical Gravity Root action Thermal expansion

What type of erosion do you think created or changed the following landmarks?1. Grand Canyon:

Erosion from water2. Niagara Falls:

Erosion from water

What has the largest impact on the speed of weathering?Changes in climate

Use the following tables to answer Numbers 10 and 11.

SOIL REQUIREMENT FOR SOME PLANTSName of plant Nitrogen Phosphorus Potassium pH requirement

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Soils Benchmark Review Packetnecessary necessary necessary

Strawberry Med Med Low 5-6Sweet corn High High High 6-7

Deciduous trees Med Low Low 5-6Evergreen trees Low Low Low 4-5.5Sweet potatoes Low Med High 4.8-6.5

Peaches Med Low Med 6-8Spinach Very High Very High Very High 6.4-7

Tomatoes Med High High 6-7Watermelons Med Med Med 6-7String beans Low Med Med 6-7.5

SOIL NUTRIENT ANALYSIS RESULTSSoil Sample Nitrogen level Phosphorus

level Potassium level pH level

A Med Low Med 7.5B Med High High 6.5C Low Low Low 4.0D High High High 7.0E Med Low Low 5.0

10. Identify which plant would be best suited for each soil sample?

Sample A - Peaches Sample B - Tomatoes

Sample C - Evergreen trees Sample D - Sweet corn

11. Which nutrient prevents strawberries from growing well in soil sample E?

Sample E would need more phosphorus to support strawberries.

12. Besides testing for nutrients, what else could you look for in the soil to see if it is healthy? Explainwhy these are good soil indicators

Insects, worms or other soil organisms. These are good soil indicators because if they are present it means that the soil is healthy and has a good amount of nutrients in it.

In the space below, answer Numbers 13 through 20.

13. What is erosion?

The movement of soil from one location to another

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Soils Benchmark Review Packet14. Name four agents of erosion.

Wind, water, ice, and gravity

15. How do glaciers contribute to erosion?

Glaciers slowly move down the slope they are sitting on, as they move they pick up soil in the ice and snow. This ends up moving the soil from one location to another.

16. What is deposition?

The process by which weathered materials carried by agents of erosion are dropped in new places

Explain the two methods used by a construction site to minimize the off-site loss of sediment.

21. Perimeter Control - Various devices (basins and traps, straw bales and silt fences) are used to slow the velocity of running water and to capture sediment.

22. Temporary Stabilization -

To control erosion of soil, plants such as trees, shrubs and grass are planted. Also, mulch can be spread out.

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Soils Benchmark Review Packet

Fill in the chart below with the Agriculture BMP that matches the picture.

Best Management Picture Name and description of the Best Management Practice

Contour farming

Description:1. Follows the hillFarming with row patterns level around the hill

Crop rotation

Description:1. 5 Year sequence for planting

Change the crops grown in a field year by year

Cover crop

Description:1. This technique helps fertility

and erosion control2. Small grain used to uptake

nitrogen and prevent soil erosion

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Soils Benchmark Review Packet

Wetlands

23. Explain why wetlands called “nature’s sponge.”

Wetlands catch runoff of rain water as it drains from the land, soaking it up before it reaches open water, such as rivers or lakes. This helps absorb any pollutants that are in the runoff.

24. Which of the following are benefits of wetlands? (Circle all that apply)A. They help control flooding.B. They provide habitats for many animals.C. They filter nutrients.D. They provide many of the foods we eat.A, B, C, and D are all benefits of wetlands.

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