Properties and erosional response of soils in a degraded ecosystem in Crete (Greece)

Abstract

To study desertification processes relating to soil erosion, a climatological and altitudinal gradient from south to north was selected in Crete (Greece) and four locations were selected along the gradient. At the locations precipitation ranged from 1400 mm/year at the highest location to 400 mm/year at the lowest. All locations are affected by the actual land use: intensive grazing, small controlled fires, and abandoned agricultural terraces. Representative soil profiles were described in the field and analyzed in the laboratory, and rainfall simulation experiments in the field measured soil erosion over different soil surfaces and land uses. Data on physical and chemical properties were obtained from the soil profiles and soil hydrology, and erosion data were obtained from the rainfall simulation experiments. Soil aggregation was studied with samples taken from the soil in the rainfall simulation plots and special attention being paid to the aggregate size distribution and the water-stable microaggregation. The interaction between climatological conditions and land use seems to be the main factor controlling soil erosion. This paper describes how the expected erosion along the gradient (from the most humid to the driest site) can be affected and disturbed by specific processes derived from land use.

Hydrological response of abandoned agricultural soils along a climatological gradient on metamorphic parent material in southern Spain

“…Another ratio has been calculated between the source runoff area (the sum of the areas with embedded RF, crusts and rock outcrops) versus sink runoff area (the sum of the areas with vegetation and areas without embedded RF). In this case, the climatic gradient is even less fulfi lled, and AB has higher values of source areas, followed by CO, with an indicative result for the values of soil degradation because, despite having the greatest rainfall, the soil conditions and vegetation cover, depleted as a result of grazing, have given rise to the greatest number of surface components that are a priori favourable to the production of runoff and therefore water erosion; similar results were obtained by Boix et al (1995) on calcareous hillslopes. Furthermore, CO is characterized by a large area of rock outcrops, localized in the lower zone of the hillside due to the steep slope (>50%) and the compact situation of the gully.…”

“…Extensive study has been carried out into soil erosion by water in the Mediterranean mountains, mainly in calcareous substratum where a combination of both the climatic gradient approach and rainfall simulation on surface components on the hillslopes were used to establish a hydrological response Boix et al, 1995;Cerdà et al, 1996;Bergkamp et al, 1999;Calvo et al, 2003).…”

Effects of cattle grazing during the dormant season on soil surface hydrology and physical quality in a moist‐temperate region

“…For example, in the Southern Piedmont, Franzluebbers et al (2000Franzluebbers et al ( , 2008 reported that cattle grazing did not adversely affect aggregate size and stability. In contrast, other studies indicated that grazing reduced stability of microaggregates (Boix et al, 1995) and macroaggregates (Proffitt et al, 1995). In the present study, the effect of grazing treatment on soil aggregation was somewhat mixed.…”

Spatial and temporal variation in two rainfall simulators: implications for spatially explicit rainfall simulation experiments

“…This is the case in the majority of published descriptions of rainfall simulation experiments, where all that is usually described is the mean rainfall intensity applied to the soil surface for a specified length of time (e.g. Boix et al, 1995;Bergkamp et al, 1996;Bergkamp, 1998;Cerda Á 1998a;Eldridge, 1998;Chappell et al, 1999). Occasionally the mean kinetic energy and drop size of the simulated rainfall are also described (Morgan et al, 1997;Cerda Á 1998b).…”