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Water management is the management of water resources under set policies and regulations. Water, once an abundant natural resource, is becoming a more valuable commodity due to droughts and overuse.
Agricultural Water Management Program (AWMP) earlier it was as Irrigation Systems and Water Management Program (ISWM) which was established in 1991 under WRRI. It was initiated with the collaboration of International Institutions like USAID (USA). At present the low water availability is one of the main constraints in increasing per acre yield and bringing more area under cultivation. The per capita availability of water has reduced from 5650 m3 in 1951 to 1200 m3 in 2003 against the international standard of 1500 m3. It will decrease to 800 m3 in 2025. Moreover, competition for water is also increasing with the rise in population, urbanization and industrialization. The domestic and industrial water uses will increase to 15% by 2025 of the available water resources against 3% in 2000. Agriculture is the major user of good quality water (93%) but its share is decreasing because of competing non-agricultural demands. The productivity of water is very low in Pakistan. Such as for cereal it is 0.13 kg m-3 of water in Pakistan against 1.56 kg m-3 in USA, 0.82 kg m-3 in China and 0.39 kg m-3 in India. This low water productivity is due to low water use efficiency as a result of conventional irrigation methods and poor agronomic practices. Under this situation there is need to utilize the available water more efficiently and wisely along with introducing innovative and high efficiency irrigation systems.
Furrow irrigation system
Furrow-bed irrigation system was tested in irrigated maize-wheat cropping system at Mardan. Research and demonstration sites were developed all over the country at 30 sites; farmers and technicians were trained in all provinces for operation of furrow-bed machinery. Irrigation performance evaluation using IPARM and SIRMOD models guided that irrigation water application effeciency in the furrow bed can be improved by optimizing the water management practices which can led to increased water use efficiency and net benefit of the farm. Moreover, wetting front movement into the centre of wide bed during normal irrigation periods can be increased by applying different rennovation methods of furrow-bed and managing higher furrow water head.
The raised bed planter designed in collaboration with Australian Centre for International Agricultural Research (ACIAR) is capable of planting five rows of wheat on wide bed (132 cm), two rows of wheat on narrow bed (66 cm), two rows of maize on the shoulders of wide beds and a single row of maize on narrow bed. The planter can maintain uniform row to row and plant to plant distance of maize crop. Results showed higher wheat (5-15%) and maize (10-26%) yield on beds than the conventional flat basin. The narrow beds used 3-7% less water while the wide beds used 16-17% less than the basin. The lower water application in the furrow-bed compared to flat basin treatments was found to be closely related to bed width. However, the middle rows on wide beds may be susceptible to poor lateral water movement which also depends on the soil type.
Sprinkle irrigation system
The centre pivot is a sprinkler irrigation system that applies small amounts of water at frequent intervals to a unit area of crop. It consists of a span of pipe which is supported on wheeled A-frame towers and is self-propelled around a central pivot point. The pipe delivers the water to the sprinklers. Water is usually delivered to the pivot point through a buried mainline pipe. The system may vary in length from approximately 60 m to 790 m (200 to 2,600 ft.) and is capable of irrigating a circular area up to 200 ha (500 ac.). Pressure required at the pivot may vary from approximately 70 kPa (10 psi) when low-pressure spray nozzles are used, to 550 kPa (80 psi) when high-pressure impact sprinklers are used. Center pivot applications have also expanded into the realm of applying not only water but also nutrients and chemicals to the crop via fertigation and chemigation. Today a grower can apply water and chemicals with precision uniformity and high irrigation efficiency. Pakistan Agricultural Research Council through its Agricultural Water Management Program, Climate Change, Alternative Energy and Water Resources Institute, National Agricultural Research Centre, Islamabad installed centre pivot systems (CPS) in all provinces for research and demonstration purposes at following sites;
National Agricultural Research Center (NARC), Islamabad 50 acres
Arid Zone Research Institute(AZRI), Bahawalpur, Punjab 19 acres
WRRI, Field Station, Thana Bula Khan, Jamshoro, Sindh 92 acres
Arid Zone Research Center (AZRC), Quetta, Balochistan 8 acres
Arid Zone Research Institute (AZRI), D.I. Khan, KPK 19 acres
Competition for water supplies
Competition for water supplies among agriculture, industry, domestic and environment is a worldwide phenomenon and same is true in Pakistan. In Pakistan there is decreased water availability reported up to 30 %. Small water streams, uneven topography, soil with low/ high infiltration rate, unreliable water supplies are constraints in efficient utilization of irrigation water. Drip irrigation system provides an opportunity to utilize irrigation water in an efficient way under these set of conditions.Drip Irrigation Systems for Fruit, Vegetables and Nurseries
Drip irrigation is a planned irrigation system in which all necessary facilities are installed for efficiently applying water directly to the root zone of plants by water emitters operated under low pressure. Two types of dip irrigation system; micro sprinklers for nurseries and over head micro sprinkler for vegetables in tunnels were designed and installed at National Agricultural Research Centre, Islamabad under water component of PAK-China collaboration project. The area covered by each micro sprinkler is 113 ft2 with a discharge of 93 Liters per hour. These systems are working with 90 % water application uniformity at pressure head of 15 psi. Micro irrigation systems are capable to apply irrigation water along nutrients to crops grown in tunnels. Under the stressed environment of D.I. Khan drip irrigation systems were designed and installed at ten different locations on farmers’ fields for orchards and vegetables. 25% water saving and 30% yield increase attracted the attention of NGOs and Progressive farmers for adaptation of these systems in the area.
The officers/staff of various agricultural extensions/water management and educational institutions are trained in basics/applied water management practices for water conservation and water productivity enhancement in irrigated and rain fed areas of Pakistan. Moreover, the program has capacity to train national manpower in sprinkler and drip irrigation systems design and management. Tailored trainings are offered in drip irrigation systems design and management, surface irrigation systems design and evaluation, hydraulic performance of sprinkler systems, Rod Kohi (spate Irrigation Systems) Management, Farm level water productivity and Trouble shooting of drip/sprinkler systems. Students from various national universities/institutions do their research work/internship as a part of their M. Phil degree program. Academic support is being provided to the students of PARC Institute of Advanced Studies in Agriculture (PIASA), National Agricultural Research Centre, Islamabad.
The program has a field hydraulic laboratory for testing and evaluation of surface, drip and sprinkler systems. There is a testing facility to evaluate various emission devices at specific pressure head. Moreover, demonstrations were developed in real life situation related to; Furrow-bed system, Micro sprinkler for nurseries and vegetables, Drip irrigation system for fruit plants, Portable sprinkler system for small farm, Solid set sprinkler system, Centre pivot irrigation system. The facilities of the program are open to any government, non-government, Private organizations, and International organization for training, research and development.