La míneria aurífera sostenible: Análisis preliminar del sistema fluvial del Río Nechí, Colombia

The present work focuses on a preliminary analysis of the fluvial system of the rio Nechi in order to identify and analyze the external forcing factors, as a first step towards developing research and tools that allow systematic analysis of the process of alluvial gold extraction and its relation with fluvial dynamics, with an emphasis on sustainability and efficient use of water and soil resources. We identified trends in patterns of erosion and sedimentation along the rio Nechf as a result of possible forcing factors of fluvial dynamics by means of an analysis of the stage-discharge relations in cross-sections at hydrometric stations ("discharge rating curves"). We present graphs of the development in time of water levels for selected discharges. We thus obtained for the San Juan station (Nl) on the rio Nechi that in the periods 1985-1989 to 2000-2004 low flow levels are presented for lower discharges, associated to a possible continuous process of degradation of the main channel. The specific gauge analysis of the El Retiro station (N2) located on the Tigui river exhibits more or less a dynamic equilibrium in the flow levels for the great majority of the flows selected from the 1996-2000 period.