Soil profiles: their significance and production.

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Carefully contrast the profile make-up of young vs. mature soils.

What causes a soil's profile to change with age?

• continued breakdown of parent rock due to shifting, freeze fracturing and other physical forces
• increasing/decreasing levels of humic material and other organic material
• increasing biota

What else?

Consider the profile make-up in the next set of ecosystem pages.

Down South, the O and A layers no longer exist? why? how can agriculture change the face of our soils?
How long will it take to develop a new O & A layer?

  Water dynamics ...........Soil life..................Profile of the soil............Soil particle size & effects..
.............soil pH.....ecosystems soils........introduction