Interception refers to

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravitational pull from clouds. The main forms of precipitation include drizzle, rain, sleet, snow, ice pellets, graupel and hai ...

that does not reach the soil, but is instead intercepted by the leaves, branches of plants and the forest floor. It occurs in the

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an ...

(i.e. canopy interception), and in the

forest floor The forest floor, also called detritus, duff and the O horizon, is one of the most distinctive features of a forest ecosystem. It mainly consists of shed vegetative parts, such as leaves, branches, bark, and stems, existing in various stag ...

or litter layer (i.e. forest floor interception ). Because of evaporation, interception of liquid water generally leads to loss of that precipitation for the

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, ...

, except for cases such as fog interception, but increase flood protection dramatically, Alila et al., (2009). Interception types text small

Intercepted

snow Snow comprises individual ice crystals that grow while suspended in the atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet ...

fall does not result in any notable amount of evaporation, and most of the snow falls off the tree by wind or melts. However, intercepted snow can more easily drift with the wind, out of the watershed.

Conifer Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All ex ...

s have a greater interception capacity than

hardwood Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes fro ...

s. Their needles gives them more

surface area The surface area of a solid object is a measure of the total area that the surface of the object occupies. The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the definition of ...

for droplets to adhere to, and they have foliage in spring and fall, therefore interception also depends on the type of vegetation in a wooded area. Mitscherlich in 1971 calculated the water storage potential as interception values for different species and stand densities. A storm event might produce 50 – 100 mm of rainfall and 4 mm might be the maximum intercepted in this way. Grah and Wilson in 1944 did sprinkling experiments where they watered plants to see how much of the intercepted is kept after watering stops. Trees like Norway maple and a small-leaved lime have an interception of approximately 38% of the gross precipitation in temperate climate. The interception depends on the leaf area index and what kind of leaves they are. Interception may increase erosion or reduce it depending on the throughfall effects.

References

External links

The Experimental Hydrology Wiki Forest Floor Interception
* Gerrits (2010
The role of interception in the hydrological cycle
PhD thesis, Delft University of Technology, The Netherlands {{DEFAULTSORT:Interception (Water) Hydrology Forest ecology

See also

References

External links