Soils, Drainage and Runoff
Goal 1: Classify soils by grain size
Watch this video first to learn how to use plot soil components on a ternary diagram:
Soil has sometimes been called ‘the
humble remains of once proud
bedrock.’ It is created from the
leftovers that remain behind after a rock is
broken down by weathering.
Geologists generally classify soil based
on the grain size of its mineral particles.
These fall into three categories:
Sand: gritty down by weathering.
Silt: dusty
Clay: fine and sticky
1. If a soil survey tells you that you
have a ‘sandy clay loam’ on your property, what does your soil have in most abundance: sand, silt or
clay?
sand
2. If you send your soil out for a test and find out that it contains 75% silt and 25% clay, what kind of
soil do you have?
Silt loam
3. Pure loam is considered to be the best kind of soil for a farm or garden and is often defined as a
soil with roughly equal proportions of sand, silt, and clay. Is that what the diagram shows?
2 yes it does show them to be about equal in pure loam
Goal 2: Run soil drainage experiments
This study source was downloaded by 100000857952895 from CourseHero.com on 01-10-2023 11:41:47 GMT -06:00
https://www.coursehero.com/file/54969689/Copy-of-online-soil-lab/
, This set of questions uses the website located at this address:
http://www.glencoe.com/sites/common_assets/science/virtual_labs/CT02/CT02.html
In this lab, you will simulate the soil type by moving the sliding bars in the “Soil Meter” to the left or
right. The name of the soil will appear as you move the bars. Once you have your soil composition
set, click test soil and wait as soil will be poured into your funnel. Then click “pour water” and wait
until 1 one drop of water falls into your beaker. Record the percentages of each soil component and
the total amount of water (ml) that had to be added before any water was able to drain through the
soil.
Soil Type Percentages Amount of water needed
to drain
Sand Silt Clay
Heavy Clay -- -- 100% 58 ml
Silty Clay 0% 50% 50% 54 ml
Silty Clay Loam 0% 70% 30% 52 ml
Silt -- 100% -- 39 ml
Silt Loam 30% 70% 0% 41 ml
Loam 40% 40% 20% 45 ml
Sandy Loam 60% 20% 20% 37ml
Loamy Sand 80% 10% 10% 27ml
Sand 100% -- -- 26ml
Answer the following questions based on your virtual experiments:
1. Which type of soil drained the fastest (IE, the least amount of water needed to be added in
order for a drip to appear)? Why do you think that soil drained so well?
Sand; it is made up of large particles which leaves a lot of room for water to move through
2. If you were farming on that type of soil, what kinds of problems would you have?
Water would drain out of the soil too fast
3. Which type of soil drained the slowest (most amount of water needed to be added)?
Heavy clay
4. If you were farming on that type of soil, what kinds of problems would you have?
Not enough water would seep into the soil
Goal 3: Find out how soils react to rainfall
The United States Department of Agriculture (USDA) classifies soils in a different way than geologists
do – by looking at how well they hold water or let it drain out after a rainfall event. Farmers need to
know whether their soils will need constant irrigation during dry spells or, on the other extreme, if they
will become waterlogged and cause crops to rot after a lot of rain.
The following table shows how the USDA groups soils by their water retention behavior.
This study source was downloaded by 100000857952895 from CourseHero.com on 01-10-2023 11:41:47 GMT -06:00
https://www.coursehero.com/file/54969689/Copy-of-online-soil-lab/
Goal 1: Classify soils by grain size
Watch this video first to learn how to use plot soil components on a ternary diagram:
Soil has sometimes been called ‘the
humble remains of once proud
bedrock.’ It is created from the
leftovers that remain behind after a rock is
broken down by weathering.
Geologists generally classify soil based
on the grain size of its mineral particles.
These fall into three categories:
Sand: gritty down by weathering.
Silt: dusty
Clay: fine and sticky
1. If a soil survey tells you that you
have a ‘sandy clay loam’ on your property, what does your soil have in most abundance: sand, silt or
clay?
sand
2. If you send your soil out for a test and find out that it contains 75% silt and 25% clay, what kind of
soil do you have?
Silt loam
3. Pure loam is considered to be the best kind of soil for a farm or garden and is often defined as a
soil with roughly equal proportions of sand, silt, and clay. Is that what the diagram shows?
2 yes it does show them to be about equal in pure loam
Goal 2: Run soil drainage experiments
This study source was downloaded by 100000857952895 from CourseHero.com on 01-10-2023 11:41:47 GMT -06:00
https://www.coursehero.com/file/54969689/Copy-of-online-soil-lab/
, This set of questions uses the website located at this address:
http://www.glencoe.com/sites/common_assets/science/virtual_labs/CT02/CT02.html
In this lab, you will simulate the soil type by moving the sliding bars in the “Soil Meter” to the left or
right. The name of the soil will appear as you move the bars. Once you have your soil composition
set, click test soil and wait as soil will be poured into your funnel. Then click “pour water” and wait
until 1 one drop of water falls into your beaker. Record the percentages of each soil component and
the total amount of water (ml) that had to be added before any water was able to drain through the
soil.
Soil Type Percentages Amount of water needed
to drain
Sand Silt Clay
Heavy Clay -- -- 100% 58 ml
Silty Clay 0% 50% 50% 54 ml
Silty Clay Loam 0% 70% 30% 52 ml
Silt -- 100% -- 39 ml
Silt Loam 30% 70% 0% 41 ml
Loam 40% 40% 20% 45 ml
Sandy Loam 60% 20% 20% 37ml
Loamy Sand 80% 10% 10% 27ml
Sand 100% -- -- 26ml
Answer the following questions based on your virtual experiments:
1. Which type of soil drained the fastest (IE, the least amount of water needed to be added in
order for a drip to appear)? Why do you think that soil drained so well?
Sand; it is made up of large particles which leaves a lot of room for water to move through
2. If you were farming on that type of soil, what kinds of problems would you have?
Water would drain out of the soil too fast
3. Which type of soil drained the slowest (most amount of water needed to be added)?
Heavy clay
4. If you were farming on that type of soil, what kinds of problems would you have?
Not enough water would seep into the soil
Goal 3: Find out how soils react to rainfall
The United States Department of Agriculture (USDA) classifies soils in a different way than geologists
do – by looking at how well they hold water or let it drain out after a rainfall event. Farmers need to
know whether their soils will need constant irrigation during dry spells or, on the other extreme, if they
will become waterlogged and cause crops to rot after a lot of rain.
The following table shows how the USDA groups soils by their water retention behavior.
This study source was downloaded by 100000857952895 from CourseHero.com on 01-10-2023 11:41:47 GMT -06:00
https://www.coursehero.com/file/54969689/Copy-of-online-soil-lab/
