Properties of Natraqualfs in the Upper Coastal Plain of Mississippi

AbstractNatraqualfs were studied on poorly drained, silty, fluvial terraces in the humid Coastal Plain region of Mississippi. They are underlain by contrasting geologic formations of different ages. The soils have fine‐loamy and fine‐silty textural families. Soil reaction of pedons ranges from extremely acid to strongly alkaline. Acid Natraqualfs are dominant on older geomorphic surfaces, and they are deeper to natric horizons than alkaline pedons. Argillic subhorizons have a SAR > 13 and an exchangeable sodium percentage (ESP) > 15 to qualify as natric horizons. Exchangeable Ca + H is greater than Mg + Na in the acid Natraqualfs. Soil extracts have relatively low electrical conductivities and electrolyte concentrations. Sulphate and chloride are the dominant water‐soluble anions. Barite is a common mineral constituent of the natric horizons.