Consecuencias de la variación de la disponibilidad hídrica en la cuenca del arroyo El Belisario, Buenos Aires, Argentina.

The study area corresponds to the basin of "El Belisario" stream, a small valley among mountains with a surface of 26 km², located in the Ventania System. The location determines the presence of social and physical elements which constitute a high environmental vulnerability facing different kinds of threats such as massive fires and avenue phenomena of a cyclic character and marked seasonal concentration. The aim of this work is to establish links between the occurrence of avenue processes and the variation of water availability in "El Belisario" basin. Newspaper articles were gathered, annual and interannual water balances were made and environmental characteristics, which favour the occurrence of these events, were analyzed. It should be mentioned that the frequency of these phenomena is low; however, its magnitude has highly harmful consequences for the population. Important economical losses are generated, owing to the negative impact on resources-risking human lives and facilities. That is why understanding the dynamics of occurrence of these phenomena is necessary for improved local development and management of resources as well as for the watering process. [ABSTRACT FROM AUTHOR]