Iowa Soil Property Maps (gSSURGO) – Geospatial Laboratory for Soil Informatics
Available Water Capacity
Volume of water held by the soil matrix available for plant uptake.
Available Soil Water Storage
Cumulative supply volume of water held by the soil matrix.
Soil Organic Matter
The concentration of humified organic material in the soil matrix.
Soil Bulk Density – one-third bar
The mass of soil at one-third bar (wilting point) suction per unit bulk volume.
Soil Water Content – minus one-third bar
Volume of water held by the soil matrix at negative one-third bar (field capacity) suction.
Soil Water Content – minus fifteen bar
Volume of water held by the soil matrix at negative fifteen bar (wilting point) suction.
Soil Sand Content
Percent of the sand particle size fraction (0.05-2 mm) in the soil matrix.
Soil Silt Content
Percent of the silt particle size fraction
(0.05-0.002 mm) in the soil matrix.
Soil Clay Content
Percent of the clay particle size fraction (<0.002 mm) in the soil matrix.
Soil Saturated Hydraulic Conductivity (Ksat)
The rate of saturated water flow through the soil matrix.
Soil pH (1:1 suspension)
The concentration of hydrogen ions in a 1:1 soil-water suspension.
Depth to Water Table
The depth to permanent saturation of the soil matrix.
Soil Drainage Class
The frequency and duration of wet periods under conditions similar to those under which the soil formed.