Keywords
irrigation delivery systems, environmental risk assessment, seawater intrusion
Start Date
1-7-2008 12:00 AM
Abstract
The cumulative effects of irrigation delivery schedule on aquifer and onagricultural soils were analysed in a study conducted on a large-scale irrigated area locatedin southern Italy. These effects likely result from the inadequate operation of the largescaleirrigation delivery system. Agriculture in the study area is market-oriented and tightlydependant on irrigation, due to hot and dry climatic conditions and to the poor distributionof seasonal rainfall. The study area is characterized by fairly high levels of groundwatersalinity likely due to intensive exploitation of the aquifer by farmers especially during peakirrigation demand periods. The concentration of groundwater pumping during these periodsresults most likely in seawater intrusion. Rising of salinity levels are in fact noted in thegroundwater from the start of irrigation season up to the months of July and August. Theeffects of alternative irrigation distribution schedules to groundwater salinity were assessedin a previous study by simulating water deliveries through a soil-water budget approachunder different combinations among crops, soils and climatic conditions. The waterdistribution currently carried out by the local managing authority poses risks both to theaquifer and to agricultural soils. The present work aimed at conducting a generic RiskAssessment and Risk Management of the soils and aquifer degradation in the study area.Risk generating processes for the major environmental hazards were clearly identified andrisks significance was also estimated. Some feasible management options were tentativelyevaluated by using different criteria such as the social acceptability, the effectiveness inrisk alleviation and the necessary costs for implementation. The Risk Assessment and RiskManagement procedures were carried out in view of eventual new agricultural/territorialplanning as well as of potential counter-measures for mitigating the existing environmentalproblems and for reducing the potential risks.
Assessment and Management of Environmental Risks Resulting from Operation of Large-scale Irrigation Delivery Systems: a Case Study in Southern Italy
The cumulative effects of irrigation delivery schedule on aquifer and onagricultural soils were analysed in a study conducted on a large-scale irrigated area locatedin southern Italy. These effects likely result from the inadequate operation of the largescaleirrigation delivery system. Agriculture in the study area is market-oriented and tightlydependant on irrigation, due to hot and dry climatic conditions and to the poor distributionof seasonal rainfall. The study area is characterized by fairly high levels of groundwatersalinity likely due to intensive exploitation of the aquifer by farmers especially during peakirrigation demand periods. The concentration of groundwater pumping during these periodsresults most likely in seawater intrusion. Rising of salinity levels are in fact noted in thegroundwater from the start of irrigation season up to the months of July and August. Theeffects of alternative irrigation distribution schedules to groundwater salinity were assessedin a previous study by simulating water deliveries through a soil-water budget approachunder different combinations among crops, soils and climatic conditions. The waterdistribution currently carried out by the local managing authority poses risks both to theaquifer and to agricultural soils. The present work aimed at conducting a generic RiskAssessment and Risk Management of the soils and aquifer degradation in the study area.Risk generating processes for the major environmental hazards were clearly identified andrisks significance was also estimated. Some feasible management options were tentativelyevaluated by using different criteria such as the social acceptability, the effectiveness inrisk alleviation and the necessary costs for implementation. The Risk Assessment and RiskManagement procedures were carried out in view of eventual new agricultural/territorialplanning as well as of potential counter-measures for mitigating the existing environmentalproblems and for reducing the potential risks.
