Andisols from four different regions of Iceland

Four soils that formed in 1- to 3-m thick tephra and eolian materials of various origins were studied. The soils have low bulk density, and Atterberg limits characteristic of field-moist Andisols. Soil reaction ranges between pH 5.6 and 6.7. Organic C contents are high but erratic. The cation-exchange capacity is generally high. These Andisols developed from sediments of complex history consisting of tephra layers deposited during episodic volcanic events that are interstratified with eolian polycycled materials of glacial-fluvial and andic origin. All the pedons were classified as Haplocryands. More than 60 000 km² of Andisols may occur in Iceland, which would constitute 5 to 6% of all Andisols in the world. -from Authors