Environmental impacts derived from the construction of retention sediments dikes in the catchment of the Quipar river (Southeastern of Spain) : effects of the approach roads

Abstract

In this paper the environmental consequences derived from the construction of retention sediments dikes in the basin of the Quipar river are studied. The approach roads to the point of construction of the dikes have an environmental cost that, in some cases, is opposite to the purpose of the above mentioned constructions and that doesn't justifies their construction because the scanty capacity of accumulation of sediments of the dike in question, or small rate the erosion of the ravine where it is constructed. The study realized in 6 ravines of the basin of the Quipar river, indicates that the relation between the mobilized soil in the approach roads and the retained soil by the dikes is 10 %, though the range of this one is between 7 % and 36 %. On the other hand, the plowed surface with bushes and pines elimination is of 40 hectares in the six studied ravines (0.7 hectares for dike), being to 1.6 hectares in one of the ravines.