How does scientists classify soil

Discuss the defining characteristic s of each of the 12 soil orders. Apply the concept of Soil Forming Factors to the formation and occurrence of each of the 12 soil orders. Identify regional scale occurrences of soil orders in the USA. Thinking questions to prepare for the lesson: Question 1: a. How would your life be different without these everyday classification schemes? Question 2: How could a map of soil types and properties be useful to: a land developer?

These levels, in order from most general to most specific, are: Order Suborder Great Group Subgroup family Series This system of Soil Taxonomy is comparable to the Linnean system used in biology to classify living things kingdom, phylum, class, order, family, genus, and species. These levels, in order from most general to most specific are: Order, Suborder, Great Group, Subgroup, family, and Series. How do scientists classify soils? You just studied 13 terms! The USCS has three major classification groups: 1 coarse-grained soils e.

The USCS further subdivides the three major soil classes for clarification. The 12 soil orders all end in "sol" which is derived from the Latin word "solum" meaning soil or ground. Most of the orders also have roots that tell you something about that particular soil.

For example, "molisol" is from the Latin "mollis" meaning soft. Explore more about each soil order. Find your state soil! Texture - The particles that make up soil are categorized into three groups by size: sand, silt, and clay. Sand particles are the largest and clay particles the smallest. Although a soil could be all sand, all clay, or all silt, that's rare. Instead most soils are a combination of the three. The relative percentages of sand, silt, and clay are what give soil its texture.

A loamy texture soil, for example, has nearly equal parts of sand, silt, and clay. Structure - Soil structure is the arrangement of soil particles into small clumps, called "peds".

Much like the ingredients in cake batter bind together to form a cake, soil particles sand, silt, clay, and organic matter bind together to form peds. Ped shapes roughly resemble balls, blocks, columns, and plates. Glacial till is material ground up and moved by a glacier.

The material in which soils form is called "parent material. Sediments along rivers have different textures, depending on whether the stream moves quickly or slowly.

Fast-moving water leaves gravel, rocks, and sand. Slow-moving water and lakes leave fine textured material clay and silt when sediments in the water settle out. Soils vary, depending on the climate. Temperature and moisture amounts cause different patterns of weathering and leaching. Wind redistributes sand and other particles especially in arid regions. The amount, intensity, timing, and kind of precipitation influence soil formation. Seasonal and daily changes in temperature affect moisture effectiveness, biological activity, rates of chemical reactions, and kinds of vegetation.

Slope and aspect affect the moisture and temperature of soil. Steep slopes facing the sun are warmer, just like the south-facing side of a house. Steep soils may be eroded and lose their topsoil as they form. Thus, they may be thinner than the more nearly level soils that receive deposits from areas upslope.

Deeper, darker colored soils may be expected on the bottom land. Biological factors. Plants, animals, micro-organisms, and humans affect soil formation. Animals and micro-organisms mix soils and form burrows and pores. Plant roots open channels in the soils.

Different types of roots have different effects on soils.