exorheic
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GC: adj

CT: The minimum amount of runoff that must be preserved in order to maintain basin salt balance is conceptually calculated. The alternative, the conversion of all runoff into evapotranspiration, is unsustainable, because it will cause salts to accumulate without limit. Nature intended exorheic drainage basins to be in salt balance by means of runoff. Therefore, to preserve this natural function, a limit must be imposed on the consumptive use of runoff through irrigation.

S: http://ponce.sdsu.edu/sustainable_runoff_for_basin_salt_balance.html (last access: 11 January 2015)

N: 1. exo– + Greek rhein, rhe-, to flow; see sreu- in Indo-European roots + –ic.
2. Of or relating to a drainage basin whose surface water runs into the ocean or into another body of water having a connection to the ocean.
3. Hydrologic basins can be either exorheic or endorheic, depending on their drainage properties. Exorheic basins have an outlet to the sea; endorheic basins do not. Exorheic basins have finite V/Q ratios, with a global average of 2. Conversely, in an endorheic basin, runoff is zero; therefore, V/Q = ∞; i.e., all precipitation is converted to vaporization.
Typically, exorheic basins feature rivers and estuaries, and drain outwards, while endorheic basins feature lakes and wetlands and drain inwards. However, some apparently closed basins (lakes) may not be fully endorheic, featuring small percentages of runoff, for instance, Lake Titicaca, in Peru. Therefore, these basins are termed semi-endorheic. Similarly, some apparently open basins (rivers) may not be fully exorheic, featuring small percentages of forced loss to vaporization (through small lakes), for instance, the saline bogs in the Upper Paraguay river, in Mato Grosso, Brazil. Therefore, these basins are termed semi-exorheic.
Fully exorheic drainages do not accumulate salts and other solids. Semi-exorheic and semi-endorheic drainages accumulate small quantities of salt. Fully endorheic drainages accumulate great quantities of salt.

S: 1 & 2. http://www.yourdictionary.com/exorheic (last access: 15 January 2015). 3. http://ponce.sdsu.edu/sustainable_runoff_for_basin_salt_balance.html (last access: 11 January 2015).

OV: exoreic

S: TERMIUMPLUS

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CR: endorheic