In USDA soil taxonomy, andisols are soils formed in volcanic ash and defined as soils containing high proportions of glass and amorphous colloidal materials, including allophane, imogolite and ferrihydrite. [1] In the World Reference Base for Soil Resources (WRB), …

Andisols form from weathering processes that generate minerals with little orderly crystalline structure. These minerals can result in an unusually high water- and nutrient-holding capacity. The central concept of Andisols is that of soils dominated by short-range-order minerals.

Andisols (from Japanese ando, "black soil") are soils that have formed in volcanic ash or other volcanic ejecta. They differ from those of other orders in that they typically are dominated by glass and short-range-order colloidal weathering products such as allophane, imogolite and ferrihydrite.

Andisols are defined by the single property of having volcanic-ash parent material. Although these soils exist in all climatic regions, they account for less than 0.75 percent of all the nonpolar continental land area on Earth .

Andisols are defined by the presence of volcanic glass in the soil. These soils are least weathered and the soils forms after breaking of cinders (pyroclastic material) and volcanic ash close to the proximity of downwind of a volcanic activity. They are younger in age forming in deposits from geologically recent events.

Key Characteristics: Andisols. Form in regions of recent volcanism; Volcanic parent materials; Generally high in natural fertility ‘Light’ soils that are easily cultivated. Potentially very productive soils; Limited geographic distribution; Extent of world ice-free land area: 1%

Parent Material: Volcanic soils, also known as Andisols, are formed from volcanic ash and cinder deposits. While most of the world’s volcanic soils are not highly weathered, there are notable exceptions on Maui. Mineralogy: Volcanic soils largely consist of non-crystalline (amorphous) minerals, such as allophone and imogolite.

2012年1月1日 · The central concept of Andisols is one of deep soils commonly with depositional stratification developing mainly from ash, pumice, cinders (scoria), or other explosively erupted, fragmental ...

2016年1月1日 · Andosols are soils of active volcanic areas. They exhibit unique soil properties that place them apart from other soils. The term ‘andosol’ is derived from Japanese, ‘an’ meaning dark, and ‘do’ connotating soil (Figure A22). Andosols are also found outside active volcanic regions when environmental conditions favor their formation.

Andisols are a unique soil order formed from volcanic ash and tephra, characterized by their high fertility and specific physical and chemical properties. These soils typically develop in areas with significant volcanic activity and are known for their ability to retain moisture and nutrients, making them ideal for agriculture.