What is meant by runoff and how is it produced?
Runoff is the part of the water cycle in which the water flows over the land as surface water rather than be absorbed into groundwater or evaporating. Runoff appears in uncontrolled surface streams, rivers, drains and sewers.
What is run off process?
Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity toward a stream channel (always above the main groundwater level) and eventually empties into the channel.
What is runoff in the water cycle?
Runoff is nothing more than water “running off” the land surface. Just as the water you wash your car with runs off down the driveway as you work, the rain that Mother Nature covers the landscape with runs off downhill, too (due to gravity). Runoff is an important component of the natural water cycle.
What causes overland flow?
Saturation Excess Overland Flow occurs when the soil becomes saturated, and any additional precipitation or irrigation causes runoff. … Increased interflow levels due to precipitation inputs. Elevated water table due to increased water inputs. Exceeded water holding capacity in shallow soil.
How does runoff cause erosion?
Rain falling on bare soils can cause erosion and create storm water runoff carrying soil particles called sediment. … When sediment settles out of the water, it gradually fills in the stream, lake bed, or wetland and can destroy fish spawning areas and other aquatic habitats.
What does a runoff do?
Runoff: Surface and Overland Water Runoff
A portion of the precipitation seeps into the ground to replenish Earth’s groundwater. Most of it flows downhill as runoff. Runoff is extremely important in that not only does it keep rivers and lakes full of water, but it also changes the landscape by the action of erosion.
What are examples of runoff?
Runoff is defined as excess water draining away from land or buildings. The overflow of water that drains off of your driveway is an example of runoff.
What is runoff and groundwater?
Runoff is the water that is pulled by gravity across land’s surface, replenishing groundwater and surface water as it percolates into an aquifer or moves into a river, stream or watershed.
What is runoff in agriculture?
noun. the portion of rainfall that runs over agricultural land and then into streams as surface water rather than being absorbed into ground water or evaporating. pollution of the lagoon from pesticides contained in agricultural runoff from the surrounding area.
What is runoff and where does it go?
And now when it rains, the water (often called runoff or stormwater) runs off roofs and driveways into the street. Runoff picks up fertilizer, oil, pesticides, dirt, bacteria and other pollutants as it makes its way through storm drains and ditches – untreated – to our streams, rivers, lakes and the ocean.
What is overland flow in geography?
Overland flow transfers water through the basin either as sheetwash, across the surface, or in tiny channels called rills. Beneath the surface, water is transferred via throughflow, which is the movement of water through the lower soil towards rivers, and groundwater flow. Groundwater flow is typically very slow.
How does runoff affect crop production?
As agricultural runoff enters bodies of water it can have negative impacts on the environment. Not only can it contaminate sources of drinking water but the chemicals in the fertilizers can be absorbed into aquatic plants, contribute to algae blooms and effect animals’ ability to find food and reproduce.
What does runoff of pesticides and fertilizers cause?
Rain water carries soil particles (sediment) and dumps them into nearby lakes or streams. … In addition, other pollutants like fertilizers, pesticides, and heavy metals are often attached to the soil particles and wash into the water bodies, causing algal blooms and depleted oxygen, which is deadly to most aquatic life.
What are examples of agricultural runoff?
6 Examples of Agricultural Runoff
- Sediment. Soil that is washed away from fields. …
- Nutrients. Nitrogen, phosphorus and potassium from chemical fertilizers and manure. …
- Pathogens. Bacteria, viruses and other harmful organics from sources such as animal waste. …
- Pesticides & Herbicides. …
- Metals. …
- Salts.
How does vegetation affect runoff?
Trees and other vegetation in urban areas considerably reduce urban-water runoff. As rain falls upon vegetation, it clings to the rough surfaces of leaves, branches, and trunks. … By intercepting and slowing precipitation hitting the ground, vegetation substantially reduces the volume and rate of stormwater runoff.
How does runoff affect the ocean?
As the rainwater enters the ocean, its speed slows and the sediment particles eventually settle out onto the seagrass beds and coral reefs and rocks lining the bays. … Sediment can also deliver pollutants to the water, bringing attached heavy metals or pesticides more swiftly into the ocean than perhaps otherwise.
What is the definition of infiltration in geography?
Infiltration – Water soaks or filters into the soil. Surface runoff – Water moves across the surface of the earth becoming a stream, tributary or river. … Percolation – Water moving from the soil into the spaces (pores) in the rock.
How do trees reduce runoff?
Trees are increasingly recognized for their importance in managing runoff. Their leaf canopies help reduce erosion caused by falling rain. They also provide surface area where rain water lands and evaporates. Roots take up water and help create conditions in the soil that promote infiltration.