By: parc.gov.pk
Introduction
The Indus Basin irrigated
agriculture is backbone of national economy and is the largest single user of
water (> 93%) in Pakistan. The level of agricultural production is
directly related to the availability and efficient use of water. With increased
water demand for domestic and industrial uses, water availability for
agriculture is decreasing, necessitating its efficient use for sustaining crop
production. Thus, the consumptive use of water (CUW; evapotranspiration)
information is essential for estimating irrigation water requirements in arid
and semi-arid regions of the country. Such information is crucial for planning,
development and management of water resources. The CUW information is also
crucial while negotiating contracts and treaties for water distribution of
major river systems.
Technology Development
The Water Resources scientists at
NARC carried out this research during 1975-1986 in collaboration with six
provincial institutes in different agro-ecological zones of the country: (i)
Arid Zone Research Institute, D.I. Khan; (ii) Agricultural Research Institute
(ARI), Tarnab, Peshawar; (iii) Sindh Agri. University, Tandojam; (iv) MRE
Project, Bhalwal; (v) LRD, Lahore; and (vi) ARI, Sariab, Quetta. The crops
studied were wheat, maize, soybean, cotton, sugarcane berseem, sorghum, barley,
rapeseed, mash-bean, gram, pea, potato, onion, tobacco, citrus and guava.
Factors affecting water use efficiency (fertilization, soil moisture stress,
irrigation level, etc) and crop water use were studied. Measured values of crop
water use/CUW were correlated to potential evapotranspiration (computed crop
evapotranspiration using climatic data) and crop coefficients were developed.
These coefficients can be used for estimating water requirement of crops for
areas where actual measurements are not available or are costly and
time-consuming. This information is used by planners, policy makers,
researchers, university students and teachers while dealing with the subject of
water.
Technology Dissemination
The findings were compiled in two
widely circulated reports. These reports summarize crop growing seasons, actual
crop evapotranspirations, moisture stress yield functions and crop coefficients
for 17 selected crops grown in major agro-ecological regions of Pakistan.
Key References
Ahmad, M., S. Mehmood, S. Ahmad
and R. Amin. (1989). Consumptive use of water for wheat in southern NWFP.
Journal of Engineering and Applied Sciences, 8:81-84.
Ahmad, S. (1989). Irrigation
scheduling as affected by planting dates for three major crops. Pakistan
Journal of Water Resources, 2:12-18.
