Stemflow: The water which trickles along the stems and branches and down the main stem or trunk to the ground surface. Interception Storage: The ability of vegetation surfaces to collect and retain Precipitation, capacity will be highest at the onset of rainfall when the vegetation is dry, when water is held by surface tension. Evaporation: Even when the interception storage capacity is exceeded water may be lost by evaporation off leaf surfaces, which increases in windy conditions, though the interception storage capacity may be reduced with increased windspeed.
Duration of Rainfall: Influences interception by determining the balance between reduced storage of water on vegetation surfaces and increased evaporative loss over time. Total interception losses increase with duration of rainfall but only gradually , though the relative importance of interception decreases with time.
The importance of interception decreases with time, due to duration of rainfall and changes in the interception storage capacity. Rainfall Frequency: The highest levels of interception loss occur when the leaves are dry and interception storage is large, so the frequency of re-wetting is more significant than the duration and amount of rainfall. Precipitation Type: The contrast between rain and snow. Snow clings to leaves and branches more, but interception loss is limited due to low temperatures and evaporation rates.
May be a contrast between coniferous and deciduous trees. Type and Morphology of the Vegetation Cover: Different vegetation types have:. Different interception storage capacities. Different aerodynamic roughness characteristics. Different rates of evaporation from their surfaces.
Interception losses are generally greater from trees than other types of vegetation grasses and agricultural crops due to the greater aerodynamic roughness of trees in promoting increased evaporation in wet conditionsor to their higher interception capacities in some cases especially when wetted and dried frequently. Interception losses are greater from coniferous forests than from deciduous woodlands. Depression storage is the term applied to water that is lost because it becomes trapped in the numerous small depressions that are characteristic of any natural surface.
When water temporarily accumulates in a low point with no possibility for escape as runoff, the accumulation is referred to as depression storage. The amount of water that is lost due to depression storage varies greatly with the land use.
A paved surface will not detain as much water as a recently furrowed field. The relative importance of depression storage in determining the runoff from a given storm depends on the amount and intensity of precipitation in the storm. Typical values for depression storage range from 1 to 8 mm 0. As with evaporation and transpiration, depression storage is generally not directly calculated in highway design.
If the soil surface has a low infiltration capacity and low hydraulic conductivity, and if the topography allows for surface storage, then water may be stored at the surface in small pools or depressions. These water-filled depressions, called vernal pools, are often seasonal features that form because of perched water tables. These depression storage areas may become hydrologically connected during high water conditions and develop a flow network to deliver water to streams or other surface water bodies.
Depression storage refers to small low points in undulating terrain that can store precipitation that otherwise would become runoff. The precipitation stored in these depressions is then either removed through infiltration into the ground or by evaporation. Depression storage exists on both pervious and impervious surfaces. The volume of water in depression storage at any time during a precipitation event can be approximated as Linsley :.
V is the volume of water in depression storage. S d is the maximum storage capacity of the depression. P e is the rainfall excess, and. Empirical Estimates of Depression Storage for storms. Sand 0. Loam 0. Clay 0. Impervious areas 0. Pervious urban 0. Singh, V. Elementary Hydrology. Prentice Hall of India Private Limited. Suggested Reading. Subramanya, K. Engineering Hydrology.
Raghunath, H. New Age International P Ltd. Site news. The difference between potential evapotranspiration and precipitation is used in irrigation scheduling. Transpiration: The process by which water taken in by tree roots from the soil is evaporated through the pores or stomata on the surface of leaves. Interception: The process by which water held on the surface of leaves, branches and trunk during and after rainfall is directly evaporated back to the atmosphere.
At the same time, total runoff, surface runoff, interflow and base flow increased by Depression major depressive disorder is a common and serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Meteorological factors affecting runoff: Type of precipitation rain, snow, sleet, etc.
Rainfall intensity. Rainfall amount. Rainfall duration. Distribution of rainfall over the watersheds. Direction of storm movement. Antecedent precipitation and resulting soil moisture. Storage — water stored in the system Interception — this is when precipitation lands on buildings, vegetation and concrete before it reaches the soil. Interception storage is only temporary as it is often quickly evaporated. Vegetation storage — this is water taken up by vegetation.
It's for automatic whereas for standard rain gauge the non-recording rain gauge is used. This discussion on In India the recording type rain gauge generally used, isa weighing typeb tipping typec float recording typed none of these.
Correct answer is option 'C'. Most precipitation reaches the ground, but not all of it, as some is stopped by vegetation, a process known as interception. The proportion of the precipitation that does not reach the ground , the interception loss, depends on the type of vegetation, its age, density of planting and the season of the year. Forest canopy interception rate IR is the ratio of canopy inter- ception divided by total rainfall measured above the canopy at certain time intervals.
Rainfall interception is the fraction of rain that falls onto vegetation but never reaches the ground , instead evaporating from the wet canopy. Evapotranspiration is the sum of evaporation from the land surface plus transpiration from plants. The typical plant, including any found in a landscape, absorbs water from the soil through its roots.
In general, evapotranspiration is the sum of evaporation and transpiration. The movement diagonally downslope of water through the soil , as opposed to the vertical movement known as percolation. It may follow natural percolines in the soil. Throughflow is a major factor in the hydrology of a drainage basin where the rocks underlying the soil are impermeable. Does interception decrease during a storm? Asked by: Tressa VonRueden.
What are the 3 types of interception? How do you calculate interception loss? What is depression storage? Where is water stored when it is intercepted? What causes water to soak into the earth? What is interception gain? How does interception affect transpiration?
Why is evapotranspiration higher in summer?
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