The flora of Hasanlar Dam Lake (Düzce) and its surroundings

This study was prepared under the title ?The Flora of Hasanlar Dam Lake (Düzce) and its Surroundings? as a master thesis at the Department of Forest Engineering, Institute of Natural Science, University of Düzce.The Hasanlar Dam Lake is situated at the northestern part of Düzce, in the northern part of The Western Black Sea Region. The total research area is 5000 ha and the elevation of the area varied between 100 and 1200 metres above the sea level. The study area is located the transition zones between two different phytogeographyc regions namely the Euro-Siberian and the Mediterranean Flora.1300 specimens were collected during 48 field trips in the research area in 2007 and 2008. 93 families, 295 genus and 537 taxa were identified. The study area is in the A3 square according to the Flora of Turkey?s grid system. 62 of the identified specimen were the new record for the A3 square. The 16 of the collected specimen were endemic, and endemism ratio is % 2.98. The rates of taxon belonging to the certain phytogeographical regions are as follows: Euro-Siberian elements: % 25.33, Irano-Turanian elements: % 1.67, Mediterranean elements: % 14,15 The rates of cosmopolitan and phytogeographycally unknown species are % 58.85.The largest family was Asteraceae (Compositae) with 34 genus, the family including the most species was Fabaceae (Leguminosae) with 66 species and the largest genus is Trifolium with 12 species.The plant life froms of Raunkiaer systems that were identified in the study area included 79 (% 14.71 ) Phanerophytes, 19 (% 3.54) Chamaephytes, 232 (% 43.20) Hemicryptophytes, 55 (%10.24) Cryptophytes [48 (% 8.94) Geophytes + 7 (%1.30) Hydrophytes] and 139 (% 25.88) Therophytes. 13 (% 2.43) taxa life forms were unknown.Key Words: Flora, Raunkiaer, Hasanlar Dam Lake, Yığılca, Düzce