Gypsic Haplosalids, aquic
(Classification by UAE Keys to Soil Taxonomy)
Gypsic Haplosalids, aquic are the Haplosalids that have a gypsic horizon that has its upper boundary within 100 cm of the soil surface and are saturated with water in one or more layers for 1 month or more in normal years at a depth of more than 100–200 cm from the soil surface.
Haplosalids are the arid soils that have a high concentration of salts but do not have the saturation that is associated with the wetter Aquisalids. Haplosalids may be saturated for shorter periods than Aquisalids or may have had a water table associated with a past climate.
Salids are most common in depressions (playas) in the deserts or in closed basins in the wetter areas bordering the deserts. In North Africa and in the Near East, such depressions are referred to as Sabkhas depending on the presence or absence of surface water for prolonged periods. Under the arid environment and hot temperatures, accumulation of salts commonly occurs when there is a supply of salts and a net upward movement of water in the soils. In some areas a salic horizon has formed in salty parent materials without the presence of ground water. The most common form of salt is sodium chloride (halite), but sulfates (thenardite, mirabilite, and hexahydrite) and other salts may also occur.
Salids are Aridisols that are unsuitable for agricultural use, unless the salts are leached out. Leaching the salts is an expensive undertaking, particularly if there is no natural outlet for the drainage water.
Aridisols, as their name implies, are soils in which water is not available to mesophytic plants for long periods. During most of the time when the soils are warm enough for plants to grow, soil water is held at potentials less than the permanent wilting point or has a content of soluble salts great enough to limit the growth of plants other than halophytes, or both. The concept of Aridisols is based on limited soil moisture available for the growth of most plants. In areas bordering deserts, the absolute precipitation may be sufficient for the growth of some plants. Because of runoff or a very low storage capacity of the soils, or both, however, the actual soil moisture regime is aridic.
Gypsic Haplosalids, aquic
(Classification by UAE Keys to Soil Taxonomy)
Gypsic Haplosalids, aquic are the Haplosalids that have a gypsic horizon that has its upper boundary within 100 cm of the soil surface and are saturated with water in one or more layers for 1 month or more in normal years at a depth of more than 100–200 cm from the soil surface.
Haplosalids are the arid soils that have a high concentration of salts but do not have the saturation that is associated with the wetter Aquisalids. Haplosalids may be saturated for shorter periods than Aquisalids or may have had a water table associated with a past climate.
Salids are most common in depressions (playas) in the deserts or in closed basins in the wetter areas bordering the deserts. In North Africa and in the Near East, such depressions are referred to as Sabkhas depending on the presence or absence of surface water for prolonged periods. Under the arid environment and hot temperatures, accumulation of salts commonly occurs when there is a supply of salts and a net upward movement of water in the soils. In some areas a salic horizon has formed in salty parent materials without the presence of ground water. The most common form of salt is sodium chloride (halite), but sulfates (thenardite, mirabilite, and hexahydrite) and other salts may also occur.
Salids are Aridisols that are unsuitable for agricultural use, unless the salts are leached out. Leaching the salts is an expensive undertaking, particularly if there is no natural outlet for the drainage water.
Aridisols, as their name implies, are soils in which water is not available to mesophytic plants for long periods. During most of the time when the soils are warm enough for plants to grow, soil water is held at potentials less than the permanent wilting point or has a content of soluble salts great enough to limit the growth of plants other than halophytes, or both. The concept of Aridisols is based on limited soil moisture available for the growth of most plants. In areas bordering deserts, the absolute precipitation may be sufficient for the growth of some plants. Because of runoff or a very low storage capacity of the soils, or both, however, the actual soil moisture regime is aridic.