Flows & Underground Water

What is throughfall?

Throughfall occurs when leaves and twigs become saturated, causing water to drip from them.

What is stemflow?

Stemflow is the movement of intercepted precipitation down the branches and main trunk of vegetation.

What is overland flow?

Overland flow happens when soil is saturated, or precipitation exceeds the infiltration rate, causing water to flow over the surface as runoff.

What is Hortonian flow?

Hortonian flow is shallow, fast-moving water that occurs when precipitation exceeds both the infiltration and depression storage capacity.

What is channel flow?

Channel flow is the movement of water in defined channels, such as streams and rivers.

What is infiltration?

Infiltration is the process by which precipitation soaks into or is absorbed by the soil.

What is infiltration capacity?

Infiltration capacity is the maximum rate at which soil can absorb precipitation under specific conditions.

What factors affect infiltration?

Infiltration depends on rainfall duration, antecedent soil moisture, soil porosity, slope angle, and vegetation cover.

What is percolation?

Percolation is the slow downward movement of water from the soil into bedrock under gravity.

What affects the rate of percolation?

Percolation rate depends on the permeability and porosity of bedrock.

What is throughflow?

Throughflow is the movement of water through soil via natural pipes and percolines, occurring above the bedrock.

What is groundwater?

Groundwater is water that has infiltrated the ground and entered the phreatic zone.

What is the phreatic zone?

The phreatic zone is the part of an aquifer below the water table where all pores are permanently saturated.

What is baseflow?

Baseflow is the slow movement of groundwater into riverbeds, contributing to river discharge.

What is the water table?

The water table is the upper layer of the phreatic zone.

What is the aeration zone?

The aeration zone lies above the water table and is seasonally wetted and dried.

What causes groundwater recharge?

Groundwater recharge occurs through infiltration from precipitation and seepage from riverbanks, lakes, and puddles.

What causes groundwater loss?

Groundwater is lost through evapotranspiration, natural discharge, and artificial abstraction.

What are aquifers?

Aquifers are permeable rocks that hold significant amounts of water.

What are springs?

Springs form when water reaches the surface after percolating through the ground.

What is the water budget equation?

The water budget equation is S = P - Q - E.

What does the water budget equation S = P - Q - E stand for?

In the water budget equation, S represents soil moisture storage, P is precipitation, Q is river discharge (runoff), and E is evapotranspiration.