IMPORTANCE OF GEOLOGICAL CHARACTERISTICS AT DETERMINING BASIN CONSERVATION BORDERS: SAMPLE OF LAKE BEYŞEHİR (KONYA) BASIN Fadim YAVUZ ÖZDEMİR * Research Assistant, Selcuk University, Engineering & Architectural Faculty. Department of City and Regional Planning Address: Selcuk University, Engineering &Architectural Faculty. Department of City and Regional Planning, Campus (42075) KONYA-TURKIYE Tel: +90.332.223.21.74, Fax: +90.332.241.06.35 E-Mail: fadimyavuzozdemir@gmail.com Özden (SOĞUCAKLI) ÖZKAN** Research Assist ant, Selcuk University, Engineering &Architectural Faculty. Department of Geology Engineering Address: Selcuk University, Engineering &Architectural Faculty. Department of Geology Engineering, Campus (42075) KONYA-TURKIYE Tel: +90.332.223.21.80, Fax: +90.332.241.06.35 E-Mail: ozdens@selcuk.edu.tr ABSTRACT Watersheds are based on hydrological borders instead of managerial or politic divisions. Watersheds are the most suitable units to conserve water resources and ecosystems and to plan the sustainable usage of them. Until now borders of river and dam basins’ are determined considering geomorphologic borders. Watersheds are supported out of geomorphologic borders; consequently detailed geological and hydro-geological characteristics of the region should be recognized while determin- ing the conservation borders. Because of its natural beauty, of bio-diversity and being the biggest fresh water source in its region Lake Beyşehir is one of the most important wetlands in Turkiye. Lake is threatened by fishing, cutting of the rushes and ensuring planting and drink- ing water. Despite the fact that ground-drainage area has a very different drainage area from surface waters in Basin of Lake Beyşehir, surface water infiltration basin was selected as border of the Lake Beyşehir Management Plan. The aim of this paper is to display the importance of watershed border, conse- quently conservation area border factor at conserving wetlands within the water- shed scale. After consulting the relevant literature and observations, The Lake Bey-