Soil is a short word that has many meanings.
Soil can be sweet smelling when freshly plowed and crumbly to touch . It can be black in color and rich in nutrients or pale brown and lacking in nutrients.
Soil has character. It is composed of mineral and organic materials in which
plants and other organisms grow. Soil is the skin of the earth that life on our
planet depends on for sustenance. Soil is not "dirt". Soil is
a complex medium that sometimes is forgotten part of the environmental picture.
Dirt is soil out of place. Our planet depends on soil for its lifeblood,
not dirt. We must protect our soil for the future well being of the
planet just as we have protected our air and water.
For More information on "Soil " go to Basic Soils Web Pages -Univ. of Minnesota
Soils are very different from one part of Minnesota to another. As you travel around Minnesota the soils are going to have different characteristics because of the soil forming factors. (Basic Soils SFF and Soil Science Education SFF). Generally soils in the west and south are going to have a thick dark surface since they were formed under prairie grasses. In the north and east the surface horizon will be thin due to being developed under a forest. Thus the native vegetation has made soils different. This map of Minnesota shows the many different kinds of soils that can be found (Minnesota Soil Map). Besides native vegetation soils are different on this map because of the differences in parent materials. This geology map of Minnesota shows the many parent materials that can be found in Minnesota( Minnesota Geology Map).
In order to verify that soils are different, a measurement technique called a transect is used. Transects are a pre-determined sampling schemes to verify characteristics of soils. ( see Transects- transect- transect) The best way to develop a transect to collect samples from many different soils would be to use a Minnesota Atlas Map (ISBN 0-89933-222-6). This map would allow you to select the points that you are going to sample by determining how many miles apart you samples are going to be.
For example, if you are planning on taking 10 samples, you could space them 10 miles apart or your total transect would be 100 miles. Alternatively you could sample at one mile intervals and your total distance would be ten miles. Using the above two maps on soils and parent materials would help in selecting transects that cross many different soils. A Minnesota highway map would not be accurate enough for you to determine exactly where you are sampling. However, a county map would also work in place of the Atlas Map.
You also can investigate soil differences in small areas. This soil forming factor is called landscape or topography. Soils are different across a landscape because of the depth to the water table and the way erosion has impacted the landscape. In using a transect across a landscape you would start at the top of a hill and collect samples as you cross the different positions on the hillslope. For example you would want to sample the summit, the shoulder, the backslope, the footslope and the toeslope. See the links Chapter 3 - Topography for more information and Using a Landscape to show how soils are different. for setting up a project on hillslopes.
For ideas on sampling soils at the site see Soil Sampling Protocol Link. In general you want to collect samples from the various horizons so you can compare the color, texture and structure of the horizons between the ten soils. You should also try to collect a soil monolith to better describe the visual differences between soils. See the link How to make a soil monolith for assistance.
To Soil Science Lab Units at the University of Minnesota
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Regents of the University of Minnesota, 2003. The University of Minnesota is an
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Prepared by terry.cooper@soils.umn.edu