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A correction to the article "Scale-dependency of sediment yield from badland areas in Mediterranean environments" that was published in the 2011 issue is presented.

While much attention has been given to erosion processes in badlands, an integrated analysis of sediment production and export rates in badland areas at various spatial scales is currently lacking. This study reviews area-specific sediment yield (SY) from badlands in the Mediterranean measured at different spatial scales, using various measuring techniques, in order to investigate the relationship between size of study area (A) and SY. A database representing 16 571 plot-year and catchment-year data on SY at 87 Mediterranean study sites was compiled. The most commonly reported lithologies associated with badlands are marls, clay rocks and mudstones, and to a lesser extent shales. A high variability of SY from badlands in the Mediterranean region is observed. The relation between A and SY for Mediterranean environments with badlands is significantly different from that reported for Mediterranean environments without badlands. A complex A-SY relationship is identified: for areas < 10 ha, SY is very high (mean SY=475 t ha—1 y—1), whereas for areas > 10 ha, SY decreases non-linearly (power law) with increasing A (mean SY=75 t ha—1 y— 1 and drops from 164.5 t ha—1 y— 1 for 10 ha 100 000 ha). This difference is explained by several factors. For A < 10 ha there is little or no sediment storage within badland areas, while for A > 10 ha progressively more sediment can be trapped in different sinks. Further, for A > 10 ha, area-specific erosion rates do not increase (or even decrease) due to decreasing average hillslope gradients and a decreasing fraction of erosion-prone (bare/badland) area. No significant relationships between SY, lithology, and mean air temperature nor mean annual precipitation were observed. [ABSTRACT FROM AUTHOR]

This study investigates the geomorphological dynamics of badland areas in the Araguás catchment (0.45 km²) in the Central Pyrenees. The genesis and development of badlands in the Central Pyrenees is favoured by the presence of Eocene marls and a markedly seasonal climate. The Aragu²s catchment has been monitored since 2004. Analysis of weathering processes and regolith dynamics showed that alternating freeze-thaw and wetting-drying cycles are the main causes of regolith development and weathering, and effectiveness and intensity of these processes is maximum in winter and summer. Evolution of the badland surfaces is related to regolith moisture level and temperature, closely associated with the season and slope exposure, which cause cyclical variations in regolith physical conditions. The most important effect associated with regolith dynamics is the temporal delay between maximum rainfall erosivity and variation in maximum surface runoff generation, reflected in seasonal differences in sediment transport. The dynamics of weathering and erosion processes affecting badland areas are the principal factors controlling geomorphological development, and the extreme hydrological and sedimentological responses of badlands are the main effects of such morphologies. From a hydrological point of view, badlands increase water production, and flood frequency relative to neighbouring areas; from a sedimentological point of view, suspended sediment transport from badland areas can reach amounts two or three orders of magnitude higher than other nearby environments. Given these results, possible responses of badland dynamics to altered hydroclimatic regime are briefly discussed. [ABSTRACT FROM AUTHOR]