Abstract
The water resources of the Indus Basin, Pakistan are mostly exploited, however the demand for water is on apermanent rise due to population growth and associated urbanization and industrialization process. Owing torapidly increasing population, the available surface water resources are not able to cope up with people's needs.The cropping intensities and cropping patterns have changed for meeting the increased demand of food and fiberin the Indus Basin of Pakistan. Cumulative effect of all sources water i.e rainfall, irrigation and groundwaterresulted in the high cropping intensities in the Basin. Presently rainfall, surface irrigation and river supplies havebeen unsuccessful to convene irrigation water requirements in most areas. Such conditions due to high croppingintensities in water scarce areas have diverted pressure on groundwater, which has inconsistent potential acrossthe Indus Basin both in terms of quality and quantity. Farmers are over exploiting the groundwater to meet thehigh crop water demand in addition to surface water supplies.The number of private tubewells has increased more than four-fold in the last 25 years. This increasingtrend of tubewell installation in the basin, along with the uncontrolled groundwater abstraction has startedshowing aquifer stress in most of the areas. In some parts, especially along the tail of canal systems, waterlevels are showing a steady rate of decline and hence - the mining of aquifer storage. Fresh groundwater areashave higher tubewell density as compared to saline groundwater zones. Even in fresh groundwater areas, uncontrolledgroundwater abstraction has shown sign of groundwater quality deterioration. Under such aquifer stressconditions, there is a need to understand groundwater usage for sustainable irrigated agriculture on long term basis.In this paper the contribution of groundwater in the irrigated agricultureof Lower Chenb Canal (LCC)East, Punjab, Pakistan is explored using a nodal network approach and water balance. Also, crop water demands,rainfall, and surface water are calculated to estimate the groundwater abstraction in different districts of LowerChenb Canal East to understand its usage patterns in year 2008-09. Crop water demand has been estimated usingSAM-ET (spatial algorithm for mapping evapotranspiration) algorithm which is based on surface energy balance.Landsat 5 TM satellite images are used to estimate actual crop water demand and the results are comparedwith Penman Monteith method. The irrigation supplies are calculated from real time data collected by ProjectMonitoring and Implementation Unit (PMIU), Punjab Irrigation Department. The PMIU envisaged for efficientand optimal canal operations oriented towards equity and transparency.Initial results from nodal network water balance model also provide the spatial variation in crop water demandfor each node in LCC East. This work is also aimed at evaluating surface water availability and theassessment of spatial distribution of groundwater abstractions by considering the present crop water demand.
| Original language | English |
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| Title of host publication | General Assembly 2010 |
| Place of Publication | Austria |
| Publisher | EGU General Assembly |
| Pages | 1 |
| Number of pages | 1 |
| Volume | 12 |
| Publication status | Published - 2010 |
| Event | European Geosciences Union General Assembly 2010 - Vienna, Austria Duration: 02 May 2010 → 07 May 2010 https://meetings.copernicus.org/egu2010/home.html (conference website) |
Conference
| Conference | European Geosciences Union General Assembly 2010 |
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| Country/Territory | Austria |
| City | Vienna |
| Period | 02/05/10 → 07/05/10 |
| Internet address |
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