IWRA Proceedings

AbstractWith the objective to carry through a space evaluation of the characteristics of used waters for irrigation in the Irrigated Perimeter Cachoeira II, together with the survey of the quality of these waters, had been carried through quarterly samplings, in a total of four samplings between the months of June of 2006 and March of 2007 in the different sources used for irrigation in the perimeter (Stream Waterfall, River Pajeú and wells). Analyses had been carried through physicist-chemistries of these waters (CE, pH, cations and anions), analyzing the results by means of descriptive statistics. It was observed independently that it has sodic chloride water predominance, of the level of salinity, the places and the sources of origin, and that the waters used for irrigation had presented increasing risk of salinization and it contains high levels of sodium and chloride. The waters of wells present values of Cl- superior the 3 mmolc L-1, arriving the average values of 19,53 mmolc L-1. The carbonate concentration presented inferior values the 0.1 mmolc L-1 in the evaluated water sources, not presenting restriction how much to its use in agriculture, keeping the values of pH inside of the normal limits (6,5 the 8,4). The biggest average values of the SAR for all the water sources had been found in the third collection (December of 2006). The waters of the wells had been the ones that had presented higher values of CE in all the collections, inside of the band of risk for many cultures of economic value. The Na+ presented as cation dominant in all the water sources despite the joined values of Ca2+ surpassing the limits praised for the irrigation (2,0 mmolc L-1). The lesser average texts of Mg+ had been found in the third collection for the different water sources.