water movement in soil

describe water movement in unsaturated soils

hydraulic conductivity (k) is unsaturated soils is DIRECTLY dependent on matric potential gradient the lower water content, lower hydraulic conductivity

is hydraulic conductivity higher in sandy or clayey

hydraulic conductivity is higher in sandy than clayey. sandy has larger pores and water is loosely held together

hydraulic conductivity (K)

indicates the ease of water flow through a specific soil

what is saturated flow

all pores (macro and micro) full of water lower horizons poorly drained soils upper horizons after irrigation or heavy rain

what is biopores vs Preferential flow

biopores: made by soil organisms- worms-help flow preferential flow: nonuniform water movement through cracks and biopores. transports contaminants to groundwater

what is unsaturated flow?

only smaller pores are filled with water, tightness with which water is held (water potential) is highly variable

What is stratification?

overlying texture (clay texture on sand or vice versa)

three types of water movement

saturated flow: soil pores are completely filled with water unsaturated flow: larger pores are filled with air, leaving only the smaller pores to hold and transmit water vapor movement: occurs as vapor pressure differences develop in relatively dry soils

what two things does hydraulic conductivity rely on?

soil texture: lower (K) in fine textured soils (clay) soil structure: macropores account for nearly all water movement in saturated soils