ABSTRACT
Carbon (C) is the principal element in organic matter and its presence is a decisive factor in determining soil quality. From the beginning of time, humankind has attempted to maintain or even increase the level of organic carbon in fields to conserve soil fertility. Soil erosion is selective in terms of preferentially removing the nutrients and colloids that are the essence of soil fertility. A runoff plot is not large enough to study the loss of soil C by water erosion in the context of climate change. Small dams in semiarid areas are very good sediment traps. The dams are of recent construction and are subject to significant siltation. The bathymetry of the reservoir was measured by localized sampling of the bottom of the reservoir, following transverse lines established by stretching a cable between the two shores. The ends of each line were leveled and positioned on the as-built drawing of the reservoir.
