Chemical behavior of the Salí River, Province of Tucumán, Argentina

Major ionic composition and other chemical parameters were determined at five sampling stations on the Salí River (Province of Tucumán, Argentina). The heavy human usage of the river causes increased levels of dissolved ions, from the dissolution of halite and gypsum, and from the weathering of basic sediments. Correlations demonstrate that sodium chloride and sulphate, and calcium carbonate are the main contributors to dissolved ions in the river. In the polluted region, south of the Celestino Gelsi dam, the main source of calcium and sulphate is the dissolution of gypsum. Large amounts of halite are also dissolved. Weathering of biotite, K-feldspar and albite are suggested by the data. Conductivity, dissolved oxygen and organic matter all indicate severe contamination by organic matter (mainly from sugar-cane processing) in the lower course. The data also demonstrate a substantial improvement in water quality before the discharge of the river at the Río Hondo dam. Data from the Colorado (a tributary of the Salí River) and Medina rivers are also analyzed and compared.     

Evaluation of a multi-model approach to estimate leaf wetness duration: an essential input for disease alert systems

Theoretical and Applied Climatology - Disease alert systems (DAS) of the AgroClimate platform are intended to facilitate grower decision-making when planning fungicide applications. These DAS...     

Correction to: Evaluation of a multi-model approach to estimate leaf wetness duration: an essential input for disease alert systems

Theoretical and Applied Climatology -     

Natural and anthropic perturbations to the chemical composition of the Colorado River (Tucumán,Argentina)

Economic and urban development in the province of Tucumán is closely associated with its hydrological network. In spite of the regulatory efforts to preserve the quality of the water resources, the lower basins of the majority of the rivers are contaminated with organic effluents derived from sugar-mill and citrus industry. In this paper, the conditions of the Colorado River basin are described. At its headwater, the lithology and geology determine the chemical composition. Calcite and gypsum dissolution and silicate influence water composition, which is slightly perturbed a few kilometers downstream by geothermal waters discharged by a tributary. Close to the discharge into the Salí River, the Colorado River receives a high organic matter load from the highly polluted Calimayo stream, which produces an increase in the organic matter and depletion of dissolved oxygen with redox conditions that promote the reduction of sulfate to sulfide.