Infiltration and Surface Runoff Quiz

The maximum rate at which the ground can absorb water.

The maximum volume of water that the ground can hold.

A thin layer of saturated soil forms at the top during infiltration.

Beneath Zone 1, a zone where soil moisture is increasing as infiltrated water moves downward.

This zone has higher moisture content than field capacity, but isn't fully saturated. Water moves downward.

The bottom zone where soil moisture is close to field capacity, becoming less saturated as you go deeper.

An occurrence where water is absorbed into the ground, like during rainfall.

The downward movement of infiltrated water through the soil.

A device used to measure infiltration rate by creating a controlled area of water infiltration. It uses two concentric rings to prevent lateral water movement and maintain a constant depth.

The process by which water enters the soil from the surface.

Water flowing across the land surface before entering a channel.

Water flowing within a defined channel, like a stream or river.

The total water flow across the land surface, including both overland flow and channel flow.

A device designed to mimic rainfall conditions in a controlled experiment. It uses nozzles to produce artificial raindrops of various intensities.

The rate at which rainfall occurs, measured as millimeters per hour (mm/hr) or inches per hour (in/hr).

The water flow that occurs when precipitation exceeds infiltration and storage capacity.

The amount of moisture present in the soil before a rainfall event. It significantly affects how much water infiltrates the ground and how much runs off.

There are three AMC types: I, II, and III. They describe how dry or wet the soil is at the start of a rainfall event. AMC-I is the driest, AMC-III is the wettest.

The soil is relatively dry, but not completely wilted. It has been cultivated, meaning it's loose and can absorb more water.

The soil is saturated, meaning it's very wet and has absorbed as much water as it can. This occurs after a period of heavy rainfall.

The Curve Number (CN) is a measure of the soil runoff potential depending on the Antecedent Moisture Condition (AMC). CNII is specifically used when the AMC is II (average).

The relationship between rainfall and the amount of water flowing in a river or stream.

A stream that flows continuously throughout the year, even during dry seasons.

A stream that flows only during certain times of the year, usually during periods of rainfall.

A stream that flows only for a short period after rainfall, often only during the rainy season.

A graph that shows the flow rate of a river or stream over time.

The sustained flow of water in a stream that is not directly from rainfall, typically from groundwater.

A statistical measure that indicates the strength and direction of the relationship between two variables, like rainfall and runoff.

Graphs showing the flow rate of a river or stream over an entire year.

Base flow is the portion of a stream's flow that comes from groundwater seepage. It's the sustained, slow flow that doesn't depend on recent rainfall. It's like a constant drip, replenished by underground sources.

Surface runoff is the water that flows over the land, not through the ground, after rainfall. It's the initial surge you see during a storm, flowing quickly over the surface.

The DRH is a graph showing the volume of water flowing in a stream after the base flow has been removed. It represents the direct effect of rainfall on the stream's flow.

Base flow is separated from the total storm hydrograph to isolate the surface runoff. It's done using different methods, like extending the recession curve of the base flow until it intersects the ordinate at the point of inflection.

Interflow is a type of subsurface flow that moves through the upper soil layers and reaches the stream quickly, making it considered part of the surface flow. It's essentially a faster groundwater flow.

The initial part of a hydrograph which shows how the discharge rises due to water accumulating in channels and across a catchment area.

The part of the hydrograph containing the peak flow, where all the runoff reaches the basin outlet simultaneously.

This represents the decrease in flow as the water stored during the event drains out.

A method of separating the surface runoff from the base flow on a hydrograph by drawing a straight line from the start of direct runoff to a point on the recession limb.

The point on a hydrograph that marks the start of surface runoff, recognizable by an abrupt change in flow rate.

The point on a hydrograph where the direct runoff ends and the recession limb begins.

This method separates base flow by extending the pre-runoff base flow line until it intersects with a vertical line through the peak flow.