The causes of piping in a set of abandoned agricultural terraces in southeast Spain

摘要: This study aims to identify some of the factors contributing piping process in abandoned terraces seven sites located Murcia Region (southeast Spain). The local landscape has appearance badland geomorphology, possessing deep valleys which until 1970s were terraced and cultivated. have now been process. research focuses on relationship between size position pipes physical geochemistry properties highly dispersive marl lithology; extent reworking materials for terrace cultivation exacerbated erosion. Morphologically, terracing stream beds resulted a series gentle benches separated by steeper risers with variable ‘drop’, (riser height). A flat infiltration surfaces result, because resculpting produces reduced bulk density infill enhanced throughflow, infiltrating water is forced along steep hydraulic gradients low outfall at base riser. Paralleling studies land levelling abandonment similar elsewhere, area shown be closely related chemical characteristics its sodicity character. Considerable differences structure, texture, mineralogical composition material's surface crust subsoil geochemical emerged from ‘site signature’ plots, these results suggest that agricultural processes affect character materials, presumably activity increases buffering effect organic acids dispersed clay. supported observation one site was levelled but not used agriculture, stable organically-distinct like formed. changes aggregate stability when occurs examined, insufficient evidence available data collected unpick causes plots. way enhance discussed, role ‘drop’ influencing pipe development illustrated. possible index describe evacuated material volumes controlling parameters discussed above tested. It concluded intended as conservation practice has, actually piping, leading farming.