Abstract:
Inland salinity is caused due to practice of surface water irrigation without consideration of ground water status. The gradual rise of ground water levels with time has resulted in water logging and heavy evaporation in semi arid regions lead to salinity problem in command areas. Inland salinity in ground water is prevalent mainly in the arid and semi and regions of Rajasthan, Haryana, Punjab and Gujarat and to a lesser e xtent in Uttar Pradesh, Delhi, Madhya Pradesh Maharashtra, Karnataka, Bihar and Tamil Nadu. In India, the problem of salinity and alkalinity increases every year as a result of secondary salinisation.
In South West Punjab areas which include districts of Firozepur, Faridkot, Bhatinda, Mansa, Muktsar and Sangrur are affected by water logging due to seepage of water from canal and salinity due to salts on the surface appeared as a white salt encrustation. In the southern part of Bhatinda district lajjal and Bagi bander are showing a maximum rise in water level around 0.05 to 0.13m/yr. because of negligible withdrawal of ground water and recharge through Bhatinda and Kotla branch canal irrigation water. In some parts of Muktsar district, waters are likely to cause both sodium and salinity hazards. Such sorts of salinity problems in irrigated agriculture prevail in some parts of Firozpur, Faridkot, Mansa and Sangrur districts also.
In order to arrest the rising trend and to save the area becoming water logged, the phreatic aquifer system is to be exploited and used the water in the conjunctive use of ground water and surface water for irrigation purpose. Cropping pattern may be changed. Drip irrigation system may be embodied which will reduces the recharge to ground water. The canal system may be monitored and breaching of canal may be repaired to decrease the ground water recharge from the canal.
Emphasis should be given on construction of multiple well point systems in linear or triangular grid pattern in massive scale to exploit maximum quantity of fresh quality of groundwater with regulated pumping for irrigation purpose, which do not mix floating good quality groundwater with the underlying saline groundwater avoiding up coning of fresh-saline water interface and create more subsurface storage for fresh ground water lenses formed from rainwater, canal seepage and return flow in the salinity affected plains of Punjab state.
An in depth study was carried out during the year 2009 at Sundarbans to investigate coastal salinity. A few of the lessons have been incorporated in this paper to aid the salinity situation in Punjab. Salt tolerant crops have been listed to improve the socio economic conditions of the farmers.
