Influence of Hudiara Drain Water Irrigation on Trace Elements Load In Soil And Uptake By Vegetables

摘要

The rapid urbanization in the cities and increasing load of population generating lot of problems formaintaining environment. The sewage and industrial effluent generated by human settlement are disposed of directly into nearby rivers / water bodies and agricultural fields. This polluted water not only contains organic matter and cropnutrients but also some toxic metals. The water of these channels may become a potential source of diseases andcontaminate our natural resources. In Pakistan it is a common practice to use industrial and sewage effluents for raisingcrops. Continuous use of such effluent could result in accumulation of metals to such a concentration that may becomephytotoxic and eventually hazardous to animal and human health. One such example is the Hudiara drain; atransboundary channel originates from India and enters in Pakistan at village Laloo. Farmers of nearby locality are usingthe untreated waste water for raising the crops and vegetables. This practice is being done at more than 4000 acres ofcultivated area along the Drain by lifting the drain’s water through electric pumps, peter engines and tractor drivendevices. The density of tubewells is 7 pumps per kilometres for irrigating the farmer’s fields and it is increasing day byday. Three points were selected for sampling the vegetables along the 54.6 km stretch of drain, each at head, middle andtail. Soil samples were taken before sowing and after the harvesting of crops. Plant samples were collected at maturityfrom all the monitoring points. At each location samples were collected at four nearby sites for detail and representativeanalysis. During the growing period of crop regular monitoring of Hudiara drain was done for water quality parameters.It was found that metal ions concentration in the vegetables was higher as specified in the standards. Similarly waterquality of drain showed increasing level of Residual Sodium Carbonate (RSC), Sodium Adsorption Ratio (SAR) andElectrical Conductivity (EC) as recommended in the water quality criteria. Dissolved Oxygen (DO), Chemical OxygenDemand (COD) and Biological Oxygen Demand (BOD) requirements of Drain water were also found higher than theNational Environmental Quality Standards (NEQS) established under the Pakistan Environmental Protection Act, 1997.It was concluded that continuous use of untreated drain’s water is not suitable for raising agricultural crops due to itsconsequences on human health and soil environment.