Rising water table on earth surface is called waterlogging. The word salinity is deduced from saline/ salt. The surplus of salt present on earth surface is known as salinity.

Waterlogging and salinity are major obstruction to the sustainability of irrigated lands and bread and butter of the farmers, particularly the small farmers in the affected areas of Indus Basin. They are eroding the valuable agriculture lands and posing a life- threatening to the country’s food security. It is roughly estimated that everyday about 500 million acres of farm lands are taken out of agricultural lands for non agricultural activities. Vast agricultural lands, particularly the poor farmers in the district, remain barren due to waterlogging and salinity.

The water table has gone very deep in the Indus Basin. The wide spread seepage water from the irrigation canals not lined and without sufficient drainage system has created serious threat of waterlogging and salinity of soil. This nuisance has further worsened due to semi- arid climatic condition, flat topography and inefficient irrigation management. It has been estimated that about 40,000 hectares of irrigated lands are wiped off due to waterlogging and salinity every year. Latest figures released by the Ministry of Environment on the “World Day to combat desertification”, show that Pakistan has lost 38 percent of its irrigated land due to waterlogging and the productivity of soil has been lost due to salinity and sodicity. 

Experts are of the firm opinion that affect of waterlogging on crop yield is astonishing. A decline in the depth of water level within five feet shows root growth and causes yield of all major crop to decrease swiftly. About 40 percent of irrigated land which produces 90 percent different kinds of agricultural crops has become under waterlogging. According to social scientists, that during every five minutes one acre fertile land is ousted from agriculture. 

Salinity is a growing problem in developing agriculture. One third of the total 20 million hectares available land for agriculture in the country has become salt affected. The affect of salinity has been serious on agricultural productivity. It alone has been causing a loss of Rs900 million every year to the national exchequer. Pakistan every year has been losing approximately 25 percent of its potential production of major crops. Nearly, 70 percent of tube wells were pumping poor quality and the percentage was higher in Sindh. According to the estimation of United Nations Environment Programme approximately 20 percent of agricultural lands and 50 percent of cropland in the world are salt-stressed.

Water deficit and salinity are affecting agricultural crops. Of the 135 million acres feet of water that flows annually to the rivers only 12 million acres feet water reach farmland. This is added by 14 million acre feet of sufficient rainfall and 45 million acre feet from tube wells. Shortage of irrigation water has been found to be the most limiting factor to solve the problem of waterlogging and salinity.

The extent of waterlogging and salinity is exhibited more in Sindh than elsewhere in Pakistan. Being near to the Arabian Sea it is also vulnerable to the salinity of ground water. Waterlogging has affected 57 percent of the agriculture cultivable land and 41 percent is under the influence of salinity. Salinity is generally responsible for about 25 percent reduction in crop production.

Since the last several years the accelerating diversion of river flows has impressively changed the hydrological balance of the irrigated areas. Initially, the irrigation system was developed without any provision for drainage, seepage from irrigation canals and water courses, and the deep infiltration of the water have slowly raised the water table, causing waterlogging and salinity. The installed drainage system in the beginning was rather successful in scaling down the water table and reducing salinity in the affected areas. However, due to negligence, poor functioning and maintenance of this system and provision of insufficient facilities for the disposal of saline drainage effluent resulted in limited success.  

Pakistan has 5.7 million hectares of land affected by salinity. The land can be reclaimed if NDP (National Drainage Programme) produce a complete and workable system to remove excess salt and water from the soil surface. Research findings reveal that some plants least affected by salinity on these lands can be easily grown and can be used as animal fodder. Biomass produced from saline lands by growing salt tolerant plants, especially kallar grass could be used directly as fodder for animals, fuel green manure or it could be converted to useful products like composite fertilizer, paper/ board, bio gas, fuel, alcohol and other products. In Sindh the Eucalyptus plants tolerate the saline lands and so these may be grown. This will make the soil fertile and will make it feasible for other crops to grow.

The Centre of Advanced Study in Applied Genetics and Saline Agriculture University of Faisalabad, has initiated a breeding programme for studying the genetic behavior of salty resistance in wheat and useful information has been obtained. The information implemented will go a long way in boosting quality production of wheat.  

In Western Australia farmers are using permanent bed technology and as a result of this they are getting high yield between 30 to 50 percent on waterlogged soils under crops such as cereal and canola. Multan farmers have used raised bed technology in 200 acres of agricultural lands for several years and as a result of this they were able to increase yield to 50 percent. Therefore permanent raised bed technology in Pakistan would have good impact to enable produce crops productively.