7
| Date post: | 19-Jun-2015 |
| Category: |
Technology |
| Upload: | sakil-ahmed |
| View: | 83 times |
| Download: | 1 times |
Introduction According to The USDA system of Soil Taxonomy Twelve soil soil orders are recognized. Andisols is one of them.
Globally, Andisols are the least extensive soil order and only account for >1% of the ice-free land area.
Parent materials Andisols, also known asVolcanic soils, are formed from volcanic ash and cinder deposits.
Most of the world’s volcanic soils are not highly weathered.
Mineralogy
Volcanic soils largely consist of non-crystalline minerals, such as allophone and imogolite.
These minerals form strong bonds with organic matter. As a result, organic matter generally accumulates in the surface horizon.
In addition to organic matter, volcanic soils may also contain high amounts of volcanic glass material with the possibility of amorphous iron and aluminum minerals.
Physical Traits Andisols are usually light.
Fluffy and are easily tilled.
Like a sponge
These soils also hold a lot of water.
Fertility
When not highly weathered, volcanic soils are typically very fertile soils. However, volcanic soils form strong complexes with phosphorus.
When poorly managed, phosphorus can be limiting.
Fertility problems may be corrected with additions of organic matter, lime and/or fertilizer amendments.
