Evaluation of the Efficiency of CROPWAT Model for Determining Plant Water Requirement in Arid Regions

Document Type : Research Paper


1 Assistant Professor, University of Tehran, Tehran, Iran

2 MSc. Graduate of Combating Desertification, Zabol University, Zabol, Iran

3 Ph.D. Student , Zabol University, Zabol, Iran


Shortage of water resources and increasing demand to consumption of this scarce resource, leads to some
noticeable limitations. On the other hand, population growth and consequently, increasing demand for water in arid
and semi arid regions , needs production in exchange of little amount of water consumption. To approach this
objective, an experiment in the complete randomized blocks carried out in four replications for cumin plant growing
in Zabol, southeastern Iran. Experimental treatments included irrigation periods at three levels. Then using
CROPWAT model, the water requirement of the plant is met. Analyzing the data resulted from production gathered
in different times of irrigation and consumption of water in the three times irrigation case with sound efficiency (1750
m3/ha), is more little than the water amount which is simulated by the CROPWAT model in 2003 (6070 m3/ha) and
(5363 m3/ha) in 2004. It then showed that this model is not effective in determining the water requirement of cumin at
this region.