Degradation of Cultivated Soils in a Semiarid Area of Greece

摘要

The soil loss, which results from the erosion processes, will be very serious, if conservation measures are not going to be undertaken very soon in central Greece. The main causes, which induce erosion in the study area, are (1) Irrigation water, (2) Torrential rainstorm, (3) Slope inclination (4) Land use and agricultural practices. The rain erosivity which was estimated using the Foumier index (FI) after analyzing the meteorological dada of the studied area is low (class 1), which means the rain induced erosion is generally low. In fact this is not exactly the real situation. Very often torrential rainstorms of usually short duration cause intense erosion (120-150 ton · ha~(-1) · y~(-1)) with heavy damages to agricultural fields and infrastructure and must be taken seriously into consideration. The estimated volume of erosion in relation to slope degree is from 21 to 310 ton · ha~(-1) · y~(-1) for inclinations 3.5% - 25%. The interpretation of aerial photography and satellite imagery] together with image analysis and GIS helped in recognizing and mapping areas with soils of higher erodibility and thus more susceptible to erosion.