What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying...
-
Upload
ashley-french -
Category
Documents
-
view
218 -
download
0
description
Transcript of What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying...
![Page 1: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/1.jpg)
SOIL ANALYSIS
![Page 2: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/2.jpg)
What is Soil?The top layer of Earth’s crust where most
plants growIt contains minerals, decaying organisms,
water, and airIt is divided into horizons, which are layers
parallel to the Earth’s surface in which the soil forms
![Page 3: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/3.jpg)
HorizonsO Horizon: also called humus, it is made up
of decaying organic matter
![Page 4: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/4.jpg)
Horizons (cont.)A Horizon:
also called topsoil, the soil is dark in color; it is made up of humus and minerals; seed sprout and plant roots grow in this layer
![Page 5: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/5.jpg)
Horizons (cont.)E Horizon:
light in color, it is made up of sand and silt
B Horizon:also called subsoil; it is a mixture of clay and minerals
![Page 6: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/6.jpg)
Horizons (cont.)C Horizon:
made up of partially broken rock; no plant roots or humus are found in this layer
R Horizon:layer made up of solid rock
![Page 7: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/7.jpg)
Soil TextureDescribes the size of the mineral particles
that make up soil There are 3 types of grain sizes:
SandSiltClay
Sand describes the largest size and clay is the smallest
![Page 8: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/8.jpg)
SandFormed by the action of wind and water
(weathering)It has a gritty feelFound in deserts, beaches, and riverbedsContains large visible particles and loses
water quickly
![Page 9: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/9.jpg)
Sand (cont.)Sand from different locations contain
different combinations of mineralsThe most common mineral in sand is quartzThere are four basic sources of sand:
Continental sand: made up of quartz, micas, feldspars and dark-colored minerals
![Page 10: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/10.jpg)
Sand (cont.)Volcanic sand: usually dark in color; found in
mid-ocean and hot spot volcanoes; has little or no quartz
Skeletal ( Biogenic) sand: made of the remains or marine organisms; has a high amount of calcium carbonate
![Page 11: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/11.jpg)
Sand (cont.)Precipitate sand: formed when the water
mixed with minerals evaporates and the minerals precipitate out; calcium carbonate will precipitate out of seawater forming layers; the layers eventually form small, round structures called oolites
![Page 12: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/12.jpg)
SiltComposed of medium-sized particlesHas a crumbly, slippery feelFound in sediment in riverbedsHas good drainage
![Page 13: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/13.jpg)
ClayComposed of small particles adhering to each
otherHas a sticky feelClumps and has poor drainage
![Page 14: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/14.jpg)
Soil SubcategoriesLoam: made up of sand, silt and clayPeat: has over 20% organic materialChalk: alkaline soil that contains various-
sized pieces of a solid, but soft, rock called chalk
![Page 15: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/15.jpg)
Collecting EvidencePhotograph and sketch the crime scene and note
where the soil samples were obtainedOnly about one cup of the top layer of soil needs to
be collectedDo not remove soil stuck to shoes, clothing or tools;
package these separately in appropriate containersCarefully remove soil from vehicles and package
these soil samples separatelyCollect additional soil samples from the four
compass points within a few feet of the crime scene and another set 20-25 feet from the crime scene
![Page 16: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/16.jpg)
Soil ProfileSeveral tests and observations are done to
create a soil profile including:ColorTextureOdorPresence of animal or plant debrisDensitypHNitrogen contentPhosphorus content
![Page 17: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/17.jpg)
DensityAll materials have a specific density and as
such, substances can be identified by their density
Density is defined as the mass of a substance per unit volume of :
density = massvolume
Objects will float at the level of their densityBased on this principle, density columns can
be used to find the density of an object
![Page 18: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/18.jpg)
Density ColumnsA density column is created by
placing very dense liquids on thebottom of a column and “floating”
less dense liquids on top of the more dense liquids
An object dropped into the column will sink to the place where its density just equals the density of the surrounding liquid
An object that sinks completely is more dense than the most dense liquid in the column
An object that floats on the surface is less dense than the least dense liquid in the column
![Page 19: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/19.jpg)
pHA measure of how acidic or basic something
isA pH of 7 is neutralA pH of less than 7 is acidicA pH of more than 7 is basic
![Page 20: What is Soil? The top layer of Earths crust where most plants grow It contains minerals, decaying organisms, water, and air It is divided into horizons,](https://reader033.fdocuments.in/reader033/viewer/2022052712/5a4d1b9b7f8b9ab0599c58db/html5/thumbnails/20.jpg)
Nitrogen and PhosphorusNitrogen is important in soil because plants
use it to make chlorophyll, the green pigment needed for photosynthesis
Phosphorus helps plants grow strong and helps in the production of flowers and fruit; phosphorus is especially important for the root part of the plant