Search results
Results from the WOW.Com Content Network
The Doña Ana County Flood Commission in the U.S. state of New Mexico defines an arroyo as "a watercourse that conducts an intermittent or ephemeral flow, providing primary drainage for an area of land of 40 acres (160,000 m 2) or larger; or a watercourse which would be expected to flow in excess of one hundred cubic feet per second as the result of a 100 year storm event."
Another commonly encountered term is the Special Flood Hazard Area, which is any area subject to inundation by a 100-year flood. [25] A problem is that any alteration of the watershed upstream of the point in question can potentially affect the ability of the watershed to handle water, and thus potentially affects the levels of the periodic floods.
A satellite image of the Sahara, the world's largest hot desert and third largest desert after Antarctica and the Arctic. Desert greening is the process of afforestation or revegetation of deserts for ecological restoration (biodiversity), sustainable farming and forestry, but also for reclamation of natural water systems and other ecological systems that support life.
In the Paraguay River portion of the Pantanal, water levels rise between two meters to five meters seasonally; water fluctuations in other parts of the Pantanal are less than this. [3] Flood waters tend to flow slowly (2 to 10 cm (0.79 to 3.94 in) per second [3]) due to the low gradients and high resistance offered by the dense vegetation.
Urban flooding is the inundation of land or property in cities or other built environment, caused by rainfall or coastal storm surges overwhelming the capacity of drainage systems, such as storm sewers. Urban flooding can occur regardless of whether or not affected communities are located within designated floodplains or near any body of water. [1]
A common example is the cactus, which has a specific means of storing and conserving water, along with few or no leaves to minimize transpiration. [8] In addition to the protection provided by spines, chemical defences are also very common. Desert plants grow slowly as less photosynthesis takes place, allowing them to invest more in defence. [8]
Farmers annually plant flood recession crops, where the land is cultivated after floods recede to take advantage of the moist soil. Dams generally discourage this cultivation and prevent annual flooding, creating a dryer downstream ecology while providing a constant water supply for irrigation.
Instead, the ground in a wet meadow fluctuates between brief periods of inundation and longer periods of saturation. Wet meadows often have large numbers of wetland plant species, which frequently survive as buried seeds during dry periods, and then regenerate after flooding. [1] Wet meadows therefore do not usually support aquatic life such as ...