Modélisation stochastique de la sédimentation d'un réservoir dans un bassin versant semi-aride

Sedimentation in large reservoirs is a major concern in semi-arid regions characterized by severe seasonal water scarcity. As a contribution to improved sediment management, this study analyses the real case of the reservoir of Sidi Yacoub in the north of Algeria. First, a dynamic model of the reservoir was set up and used to estimate past water and sediment inflows (period 1990-2010) based on data recorded by the dam operator and measurements at a gauging station located downstream of the reservoir. Second, in a stochastic framework using the statistical characteristics of inflow and outflow discharges, a projection of future sedimentation was performed until 2030, assuming stationarity of the statistical distributions. Third, the model was used to investigate the influence of possible climate change and to quantify the positive effects of soil conservation measures upstream

A relação entre o social e o natural nas abordagens de hazards e de desastres The relation between the social and the natural in the approach of hazards and disasters

O artigo aborda as teorias dos Hazards e dos Desastres. Nos últimos anos estas duas tradições teóricas têm recebido novos impulsos pela renovação de seus marcos de referência conceitual. Construídas em torno de uma longa tradição de pesquisa empírica, estas teorias explicam os impactos provocados por fenômenos como enchentes, terremotos, tornados e epidemias mediante a integração analítica das dimensões natural e social. Neste sentido, seu estudo pode fornecer subsídios para a interpretação destes problemas no Brasil.<br>The article deals with the theory of hazards and disasters. Over the past years, these two theoretical traditions have received new impulse through the renovation of their conceptual foundations. Constructed around a long tradition of empirical research, these theories explain the impacts brought by phenomena like floods, earthquakes, tornadoes and epidemics through the analytical integration of social and natural dimensions. In this regard, its study may provide grants in order to interpret these problems in Brazil