Soil Flashcards
What is soil made of?
Disintegrated rock, broken down organic matter, gas, water, nutrients, and biological organisms
1 teaspoon of soil can contain up to _ bacteria, _ fungi, _ algae, and _ protists.
100 million; 500,000; 100,000; 50,000
Soil is a _, but slowly _.
Renewable resource; regenerated
What are 3 things that soil does?
Supports plants, holds water, and brings us food
Because of the biodiversity, soil is actually considered a _.
Microecosystem
Starts with _, the geological material that breaks down and forms sediment.
Parent material
Parent material could be…
Mountainous rock, lava, sand dunes, glacier, river sediment, or bedrock
Parent material is broken down by either chemical or physical processes called _.
Weathering
The weathering of parent material is just the first step of soil formation. The second step of soil formation is erosion, which is…
The movement of particles from one location to another
Once broken down and carried away, rock debris will combine with organic matter, microbes, and other materials to form soil. However, it will still exist in different _, or layers.
Horizons
What are the different horizons?
O Horizon: Organic little layer A Horizon: Topsoil B Horizon: Subsoil C Horizon: Parent material R Horizon: Bedrock
_ is the most important layer with respect to plants as this is where they gain their nutrients and food from. The nutrient content, ability to hold water, and depth will ultimately determine how well the plant will grow.
Topsoil
Organic matter decreases as you travel down the horizons. The movement of nutrients through layers is known as _.
Leaching
There are 12 classifications of soil that soil scientists use that derive from where they originated. However, there are easier ways to classify soils…
Soil color: Can sometimes indicate infertility
Soil texture: Size of parent material particles
Soil structure: The “clumpiness” of soil
Soil pH: The acidity of the soil
Ultimately soil is affected by its regional characteristics. Some areas allow for more _, how plants uptake nutrients. Finer texture and more organic matter make for better _.
Cation exchange
Which has better soil, the Amazon rainforest or the Kansas plains?
Kansas plains
_ is a huge problem in American agriculture. Almost equally as important is _, or the arrival of the eroded material at a new location.
Erosion; deposition
We have increased erosion by the following practices…
Overcultivating fields, overgrazing rangelands, and clearing forests
There are 3 main types of soil erosion…
Splash erosion, gully erosion, and rill erosion
After a long time of erosion, the end product is the removal of topsoil and loss of nutrients of plants. As this happens, plants and vegetation die, driving erosion even deeper. This process is called _, because ultimately, you are forming a desert looking area.
Desertification
There are 6 different ways that farmers can fight soil erosion…
Crop rotation, contour farming, terracing, shelterbelts, intercropping, and no-till farming
Whenever we water our crops artificially, we call it _.
Irrigation
Ultimately, over-irrigation can deposit salt and excess nutrient sediments on the soil’s surface as the water evaporates. Over time this builds up the salt levels on the surface and leads to a process called _, that ultimately kills plants.
Salinizaton
You can stop salinization by…
Not over-watering, ya dingus!
_ generally happens faster than soil formation can occur.
Erosion
Soil texture consists of three categories…
Sand, silt, and clay (arranged from largest particles to smallest particles).
There are 3 different kinds of soil in Denton County…
Texas Blackland Prairie (East), Cross Timbers (Central), and Grand Prairie (West)
Some soils you should know…
Oxisols: Rainforest Vertisols: Denton soil Aridisols: Desert Ultisols: Deciduous forest Mollisols: Plains (most nutrient-rich)
