Terms of Hydrology (L)

labelling; labeling (A) :

Adding a tracer to water or to sediment to follow their movement.

lagoon :

Shallow body of water which has a shallow, restricted inlet from the sea.

lag-time :

Time from centre of mass of rainfall to centre of mass of runoff, or to the ...

lake :

Inland body of water of considerable size.

lake ice :

Floating ice formed in lakes.

lake percentage :

Proportion of river basin covered by lakes, in percent.

laminar flow :

Flow of a fluid in which the viscous forces are predominant. In channel flo ...

land ice :

Ice which forms from rain or snow on land.

Laplace equation :

Second-order partial differential equation of the elliptic type. In groundw ...

laser :

Instrument which permits (intense) pulses of light waves to be directed in ...

lateral inflow :

Inflow of water to a river, lake or reservoir along any reach from the part ...

Leaching :

(1) Removal of salts from upper soil layers by relatively salt-free water. ...

leaching requirement :

Fraction of the water entering the soil that must pass through the root zon ...

Lead :

Navigable passage through floating ice.

leakage :

In groundwater, the flow of water from or into an aquifer through an underl ...

leakage coefficient :

Quantity of water that flows across a unit area of the boundary between the ...

leakage factor :

Characteristic length for a leaky aquifer (large for little leakage and vic ...

leaky aquifer :

Aquifer overlain and/or underlain by a relatively thin semi-pervious layer, ...

lethal concentration :

Concentration of a toxic substance at which 50% of the fish, or any other t ...

levee :

Water-retaining earthwork used to confine streamflow within a specified are ...

limnograph :

Continuous record of stages on a chart made by a water level recorder (limn ...

Limnology :

Science that deals with the study of lakes and open reservoirs, including h ...

lipids :

Collective name for oils, fats and waxes.

Litter :

Uppermost layer of organic debris, composed of freshly fallen or slightly d ...

live storage :

Volume or cubic capacity of a lake or reservoir between the maximum and min ...

local inflow :

(1) Water entering a stream between two gauging stations. (GHP) (2) Flow in ...

log-normal distribution :

Transformed normal probability distribution in which the variate is replace ...

longitudinal section :

Vertical section along a channel at its centre line.

long-term hydrological forecast :

Forecast of the future value of an element of the regime of a water body fo ...

loop rating curve :

Double-valued part of the rating curve in which the higher values of the di ...

losing stream :

Stream or reach of stream that is losing water to the ground, and contribut ...

low water :

(1) State of the tide when the water level is lowest for any given tide (ti ...

lower reach :

Part of a stream channel in the lower region of a drainage basin.

low-flow channel :

Stream channel occupied during periods of low flow.

Lysimeter :

Vessel containing local soil placed with its top flush with the ground surf ...