Soil
and Water Conservation Programme
Pakistan has a total geographical area of 79.61 mha out of which 35.14 mha are culturable. Of the total culturable land, only 53.9% is irrigated while the rest is rainfed (3.24 mha), culturable waste (9.08 mha) and under forest (4.01 mha). The annual rainfall varies from less than 100 mm in south/south-west (Sindh, Southern Punjab and most of Balochistan) while it steadily increases towards north and reaches to nearly 1200 mm in Himalayan Piedmont region.
In the past, all-out efforts have been focused on improving the agricultural production of irrigated areas and very little attention has been paid to exploit the potential of Barani lands. In order to feed the increasing population of the country, ways and means must be devised to conserve and manage soil and water resources of "Barani" areas for improving agricultural production.
Barani areas are broadly classified on the basis of annual rainfall as:
high rainfall zone
medium rainfall zone, and
low rainfall zone
High Rainfall Zone
The high rainfall zone with annual rainfall above 750 mm lies in the northern hilly tract which serves as watershed with little use for agricultural production. However, this water could be stored in large reservoirs
to be used for irrigation purpose and recharge of
groundwater.
Medium Rainfall Zone
In medium rainfall zone with annual rainfall ranging
450-750 mm, only winter wheat can regularly and economically be grown under
improved soil moisture conservation techniques.
Low Rainfall Zone
In low rainfall zone with annual rainfall below 450 mm, the crop production is negligible and the agricultural use of land is generally limited to grazing.
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Degraded Lands |
Marginal Lands |
MAIN ISSUES
The major issues/constraints of these areas are listed below:
Erratic rainfall causing water loss through run-off
Soil erosion
Degradation of vegetation due to uncontrolled grazing and cutting causing desertification
Low agricultural productivity
OBJECTIVES
To develop, adapt and demonstrate integrated land and water use techniques using sub-watershed/catchment approach.
To improve the productivity and management of land, water and vegetation for cropland, gully-eroded areas and waste land.
RESEARCH ACHIEVEMENTS
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Rainfall-Run-off
Relationship
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Ipil-Ipil on Gully Lands |
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Rain
Water Conservation and Utilization
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| Wheat with Conserved Water | |
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Vegetative
Cover
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Demonstration
of Land and Water Use Model |
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Fruit in Eye-Brow Terraces |
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Steep Slope Afforestation
Plantation of forest plants (Euclyptus, Leucaena, Ailanthus) in the eye-brow terraces on steep slopes increased farmers' income 3-4 times after 3 years
Low-cost Conservation Structures: Developed low-cost structures (brush wood, loose stones) which rehabilitated gullied areas. These structures are easy to install and economical
Plantation in Polyethylene Bags: Plantation of fruit/forest plants in plastic bags (20 kg capacity) increased survival rate upto 90% reducing the water requirement to 1/10th of that planted in the field.
Rod-Kohi System
Major Rod Kohi areas traversed by hill torrents
constitute nearly 65 percent of the total area of Pakistan and encompass entire
Balochistan i.e. (Makran coastal Basin and Kharan closed Desert Basin). The
other major hill torrent areas include D.G.Khan and D.I.Khan, FATA and AJK. In
Sindh province, the systems are spread in Dadu district (Kirthar range). There
are around 17.13 million acres as the potential area under hill torrent / Rod-Kohi
/ Sailaba fanning excluding riverine areas. In these areas major constraint is
the use of flood flow which is highly variable in quantity and distribution,
both in time and space. Annual rainfall is low, uncertain and patchy. Flow is
laden with high silt in each flood. Poverty in these areas is a major issue. The
farming system is characterized by extreme events of floods and droughts. The
Rod-Kohi system usually entails the construction of an earthen diversion weir
with large channel on one or both sides of the river to convey flood water
across large distances. These earthen diversion structures and water conveyance
system are constructed by the communities themselves, making use of traditional
technology. Farmers construct field by making embankments from 3 to 6 feet high
to store the water. The economic significance of Rod-Kohi Irrigation agriculture
is centered around subsistence agriculture and live-stock raising which are the
main sources of income.
The institute initiated a project during 1994-95 based on integrated approach for development and management of Rod-Kohi Irrigation system for varying climatic zones spread in Sulaiman and Kirther ranges. Different types of interventions were tested and adapted with the participation of local communities. Emphasis was given on technologies related to improvement of water conveyance system, distribution, diversion and water application structure. The following interventions were carried out in different climatic zones of Pakistan:
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Water Distribution Structures. Most critical element in managing Rod-Kohi System is diversion and distribution structures, which perform both under low-and high flows and provide water according to their water rights. The structures were constructed using different construction material to allow discharge of around 150 to 230 cusecs. Cost of these structures ranged between Rs. 10000 and Rs. 20000. Farmers shared about 50% costs of these structures. |
Brick Masonary Water Distribution Structure |
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Water Diversion
Structures |
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4 Gated Diversion Structure |
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Remodeling of
Rod-Kohi Conveyance Irrigation. |
Rehabilted Water conveyance Irrigation System |
Water Application Structures
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The cultivated fields in Rod-Kohi areas are large in size (8 - 10 acres or more). The water application to the fields is crucial to control water in the flood season. Cost effective water application structures using brick masonry and pre-casted pipe nacca structure have been developed. The structures were constructed on the basis of feasibility, adaptability and farmers perception. The cost of brick masonary structures ranges between Rs. 1500 to 5000. The structures allow safe flow of 20 to 70 cusecs discharge. Pre-cost pipe Nacca is a control device which is used to divert desired amount of water to the fields. Nacca lids are easy to operate and vandalism is much less compared to wooden planks. The pre-caste Nacca of different diameters were used to construct appropriate structure for |
Water Application Structure |
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spate irrigation systems using brick masonary with number of pipes considering the area to be irrigated and amount of water required. The cost of structure varies from Rs. 1800 to 4000 with a capacity of 10 - 20 cusecs. The farmers are now adapting this technology to irrigate field to field and as water disposal structure. |
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SCIENTIFIC INVOLVED
1- Mr. Zaheer-ul-Ikram PSO
2- Mr. Muhammad Aslam, PSO
3- Mr. Abdul Ghafoor Mangrio, SSO
4- Mr. Matiullah, SSO
5- Mr. Muhammad Saleem, SO
Contacts Details:
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Muhammad Saleem Pomee, SO/ PL SWC |
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WRRI, NARC, Park Road,
Islamabad. Ph. No. 92-519255022, 9255012 / Ext 3636 |
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