MULTIVARIATE ANALYSIS TO EVALUATE GEOCHEMISTRY OF GROUNDWATER IN VARAHI RIVER BASIN OF UDUPI IN KARNATAKA (INDIA)

Water is very vital for nature and can be a limiting resource to human and other living beings. Without a well functioning water supply, it is difficult to imagine productive human activity be it agriculture or livestock. Groundwater is the main source of irrigation in arid and semi-arid regions in the world. The quality of water is of at most importance to quantity in any water supply planning and its quality is influenced by natural and anthropogenic effects including local climate, geology and irrigation practices. The quality of any groundwater is a function of the physical, chemical and biological parameters, and could be subjective, since it depends on a particular intended use (Tatawat and Chandel, 2008). Over the few decades, competition for economic development, associated with rapid growth in population and urbanization, has brought in significant changes in land use, resulting in more demand of water for agriculture, domestic and industrial activities. Irrigated lands contribute significantly to the world agriculture output and food supply. India is one of the agriculture based countries. Water used for irrigation can vary greatly in quality depending upon the type and quantity of dissolved salts. Salts present in irrigation water in relatively small but significant amounts, usually originate from dissolution or weathering of the rocks and soil, including dissolution of lime, gypsum and other soil minerals. These salts are carried with the water to wherever it is used. In the case of irrigation, the salts are applied with the water and remain behind in the soil as water evaporates or is used by the crop. In irrigated agriculture, the hazard of salt water is a constant threat