Environmental impacts on Greek wetlands

Abstract

This study identified the possible impact of anthropogenic activities on the ecological character of Greek wetlands. The objectives of this project were a) to record the anthropogenic activities that caused change in a wetland’s ecological character and assess their intensity for each wetland site and b) to identify the most significant environmental impact on each type of Greek wetland. Nineteen factors of degradation (intensive human activities) were identified and grouped in one of the impact categories according to their most significant direct impact. These degradation factors were grouped into four categories for impact evaluation: change in water regime, depletion of wetland resources, change in water quality, and loss of wetland area. To inventory anthropogenic activities and their possible impact on the ecological character of Greek wetlands, more than 1200 questionnaires were distributed, selected, and processed to compile information. These data for 291 wetlands were compiled into a data base GRIN (GReek INventory) that provides information on the factors of degradation of different kinds of wetlands (deltas, estuaries, lagoons, lakes, reservoirs, rivers, marshes, and springs). The following factors most frequently impacted Greek watlands: a) construction of irrigation schemes and diversion of water courses, causing changes in water regime (12%); b) overpumping, land clearing, and illegal hunting, causing depletion of natural resources (26%); c) agricultural and municipal pollution, causing changes in water quality (54%); and d) establishment of housing facilities and expansion of agriculture, causing loss of wetland area (32%). Change in water regime affected 50% of the springs and 40% of the rivers, natural resources depletion affected 42% of the deltas and 41% of the reservoirs, loss of wetland area affected 60% of the marshes and 52% of the estuaries, while all deltas and 75% of rivers had their water quality impacted.