Search results
Results from the WOW.Com Content Network
Pores (the spaces that exist between soil particles) provide for the passage and/or retention of gasses and moisture within the soil profile.The soil's ability to retain water is strongly related to particle size; water molecules hold more tightly to the fine particles of a clay soil than to coarser particles of a sandy soil, so clays generally retain more water. [2]
Water retention curve is the relationship between the water content, θ, and the soil water potential, ψ. The soil moisture curve is characteristic for different types of soil, and is also called the soil moisture characteristic. It is used to predict the soil water storage, water supply to the plants (field capacity) and soil aggregate stability.
The process of infiltration can continue only if there is room available for additional water at the soil surface. The available volume for additional water in the soil depends on the porosity of the soil [7] and the rate at which previously infiltrated water can move away from the surface through the soil. The maximum rate at that water can ...
A water balance states that the amount water entering the soil must be equal to the amount of water leaving the soil plus the change in the amount of water stored in the soil. The water balance has four main components: infiltration of precipitation into the soil, evapotranspiration, leakage of water into deeper portions of the soil not ...
Water moves in soil under the influence of gravity, osmosis and capillarity. [7] When water enters the soil, it displaces air from interconnected macropores by buoyancy, and breaks aggregates into which air is entrapped, a process called slaking. [8] The rate at which a soil can absorb water depends on the soil and its other conditions.
No-till farming improves water retention: crop residues help water from natural precipitation and irrigation to infiltrate the soil. Residue limits evaporation , conserving water. Evaporation from tilling increases the amount of water by around 1/3 to 3/4 inches (0.85 to 1.9 cm) per pass.
The nominal definition of field capacity (expressed symbolically as θ fc) is the bulk water content retained in soil at −33 kPa (or −0.33 bar) of hydraulic head or suction pressure. The term originated from Israelsen and West [ 1 ] and Frank Veihmeyer and Arthur Hendrickson.
Soil water can refer to: Soil#Soil moisture - water in soil; Soil water (retention) - water-holding phenomenon inside soil; Blackwater (waste) - wastewater related to effluent from water closets, toilets and urinals