A STUDY ABOUT THE EFFECTS OF IRRIGATION SCHEMES OF BUYUK MENDERES BASIN ON RIVER WATER QUALITY AND ENVIRONMENT

Ebru Yilmaz, Cengiz Koç

Abstract
    In this study, it was researched the effects of irrigation schemes that took place in Buyuk Menderes River basin on river water quality and environment. About 220,000 hectares in Buyuk Menderes basin are irrigated with irrigation scheme built sequentially. The main water source of the basin is the Buyuk Menderes river. The water, stored in dams built in the basin is given to irrigation schemes in terms of basin irrigation scheduling. The quality of water in the storage facilities is used in the irrigation scheme built along the river and after that it returns to the river again. The water returning from an irrigation scheme in river basin irrigation system becomes the source of irrigation water for other scheme. Therefore, the quality of the water released from storage facilities (dams) shows considerable differences in both irrigation schemes and along the river. On the river and at the entry points of irrigation schemes, stations were determined and water samples were taken these stations in order to research water quality along the river and to determine negative effects of irrigation areas on water quality and environment. After that these water samples were analyzed in the laboratory and changes were examined. In the water samples, changes on EC, pH, Na, K, Ca, Mg, Cl, NO₂-N, NO₃-N parameters were examined, the effects of the water samples on river water quality and environment were researched and some recommendations were presented about the study.

Key words: Menderes River, water quality, irrigation schemes, environment, Turkey