What is the Thornthwaite method?
The Thornthwaite (1948) equation is a widely used empirical method for estimating potential evapotranspiration (PET). The equation only requires mean monthly air temperature and mean daily daylight hours for each month, which can be calculated from latitude.
What is water balance model?
Water balance models describe computational aspects of water movement through the water cycle, thus can indeed be considered as a subgroup of hydrological models.
What is soil water balance method?
The soil-water balance model uses a simple accounting scheme to predict soil-water storage, evaporation, and water surplus. Surplus is precipitation which does not evaporate or remain in soil storage and includes both surface and sub-surface runoff.
What is the use of lysimeter?
A lysimeter (from Greek λύσις (loosening) and the suffix -meter) is a measuring device which can be used to measure the amount of actual evapotranspiration which is released by plants (usually crops or trees).
What is water balance analysis?
The water balance analysis reveals the percentages of precipitation made up by surface flow, evapotranspiration, groundwater recharge and the change of soil storage, all of which are considered useful to the further understanding of the hydrological processes in the Xitiaoxi catchment.
How do you calculate soil water budget?
In its simplest form:
- Change in Soil Water = Inputs of Water – Losses of Water.
- Change in Soil water = (P + I + C) – (ET + D + RO)
- S = P + I -ETc (SMa / t)
How does a lysimeter work?
The sampling lysimeter (Figure 1), also known as a pore water sampler, is an apparatus for the sampling of moisture from the soil. Moisture moves from the soil through a porous ceramic cup into some container for later collection. The movement of water occurs due to a vacuum being pulled on the ceramic cup.
How do you find potential evapotranspiration?
the FAO+56 IS THE BEST AND ACCURATE FORMULA FOR CALCULATING THE ET0. Potential evapotranspiration (ETP), expressed as the evaporated water slice, is the sum of the amounts of water that can evaporate and transpire on a given surface and for a well-defined period of time, considering inputs from sufficient water.