Environmental and Soil Degradation in Farsala Catchment Area.
Telemachus Lelentjis Sr., NAGREF - Institute for Soil Classification and Mapping, Theophrastou 1, Larissa, Greece and Christos GianakopoulosI Sr., National Observatory of Athens - IERSD, I. Metaxa, Vas. Pavlou, Athens, Greece.
The International Standards Organization defines land degradation as “the process in which the land due to natural processes or human activity is no longer able to sustain properly an economic function and/or the original natural ecological function” (ISO, 1996). Soil degradation is expressed by the decline in soil qualities commonly caused through improper use by humans (ISSS, 1996). Land degradation of Farsala catchment area, in an area of about 85000 ha, includes soil erosion by water (sheet erosion, rill erosion, gully erosion in moderate or strong slopes 6-18 %), deterioration of the (physical, chemical and biological or economic) properties of soil and the long-term loss of natural vegetation. In order of magnitude and intensity, the land degradation factors are reported as follows: soil erosion, desertification, and scarcity of water resources, reduction of soil fertility and of organic matter content. In the area, the precipitation is less than 600 mm (436 mm) annually, so calsic horizons are formed. The soil of Farsala area was formed in alluvial deposits of quaternary and tertiary period. The last decades, the severe environmental conditions like drought, desertification, and soil erosion has highlighted the need to develop effective monitoring tools and to pursue research on the immediate and long-term impact of these events. Much of the land is mismanaged. Sloping lands are under the increasing threat of erosion and overgrazing. Flat lands are being explored continuously without little inputs added to the soil, however, the biggest threat is the alarming urbanization by home construction, building highways and business, which are “swallowing” enormous areas of very fertile land. The dominant land degradation factor is soil erosion (irreversible aspect), which is accelerated by the removal of natural vegetation from the slope lands and the conversion of these areas for cultivation of crops. This is particularly the case of the hilly tertiary deposits in Enipeus river basin, which are characterized by long slopes, soft geologic material (marl) and severe climatic conditions. The implications of environmental degradation and constraints on agricultural productivity can be listed as follows: Soil erosion is a menace of the cultivated slope lands, principally on the widely extensive sloping lands with shallow soils of the area. Land resource consumption by factory buildings and infrastructure, is more evident the last years. Overgrazing, cultivation and stubble burning cause the destruction of soil organic matter (slowly reversible aspect). The future global climate change scenarios suggest that these events will cause more serious environmental and socio-economic implications. All above, are worse than the “clash of civilizations”, a theory devoid of substance compared to the environmental degradation.