Assessing the Global Water Productivity of Some Irrigation Command Areas in Iran
The great challenge of the agricultural sector is to
produce more crop from less water, which can be achieved by
increasing crop water productivity. The modernization of the
irrigation systems offers a number of possibilities to expand the
economic productivity of water and improve the virtual water status.
The objective of the present study is to assess the global water
productivity (GWP) within the major irrigation command areas of
I.R. Iran. For this purpose, fourteen irrigation command areas where
located in different areas of Iran were selected. In order to calculate
the global water productivity of irrigation command areas, all data on
the delivered water to cropping pattern, cultivated area, crops water
requirement, and yield production rate during 2002-2006 were
gathered. In each of the command areas it seems that the cultivated
crops have a higher amount of virtual water and thus can be replaced
by crops with less virtual water. This is merely suggested due to crop
water consumption and at the time of replacing crops, economic
value as well as cultural and political factors must be considered. The
results indicated that the lowest GWP belongs to Mahyar and
Borkhar irrigation areas, 0.24 kg m-3, and the highest is that of the
Dez irrigation area, 0.81 kg m-3. The findings demonstrated that
water management in the two irrigation areas is just efficient. The
difference in the GWP of irrigation areas is due to variations in the
cropping pattern, amount of crop productions, in addition to the
effective factors in the water use efficiency in the irrigation areas.
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