No abstract

Coastal dunes are particular ecosystems because they include different vegetation types and have high environmental heterogeneity. Plant biodiversity in coastal dunes vary along the seashore to inland environmental gradient. In the present study, plant biodiversity along the coastal dune zonation of Central Black Sea Region of Turkey (upper beach or drift line, embryonic or primary dune, main dune, transitional and fixed dune zone) is evaluated using different diversity indexes (Evenness, Functional diversity, Plant biodiversity and Rarity). Plant biodiversity increases from seashore to the inland. In particular evenness and rarity indexes tend to increase from the drift line to fixed dunes as functional diversity is high in the upper beach and drift line.

Coastal erosion resulted in dramatic changes in the structure of coastal dune communities for example many characteristic species may be removed from dune zones. The effects of coastal erosion on coastal dune communities in north of Turkey were investigated along seashore-inland gradient. It has been found that the severity of erosion caused to increase the differences among coastal dune communities. Our results also implied that embryonic shifting dunes represented by Achilleo maritimo-Elymetum farcti (EU Habitat 2110) and shifting dunes along the shoreline with Ammophila arenaria (white dunes) represented by Medicagini marinae-Ammophiletum arundinacea (EU Habitat 2120) were more prone to coastal dynamics. It has been found that the severity of erosion caused to increase the differences among coastal dune communities.

Plant co-occurence patterns were studied in coastal dunes in Central Black Sea Region of Turkey (North of Turkey) by the help of the checkerboard score (C-score), and the checkerboard score for abundance data (CA-score) along climatic and local gradients. There were significant differences along the local and climatic gradients with respect to both standardised C-and CA-scores. Standardised C-scores were found to be significantly different along sea-inland gradient except for fixed dune zone, while standardised CA-scores were significantly different in embryonic and main dune zones. Our results were supported HBR (humped-back relationships) hypothesis in studied coastal dunes because standardised scores were usually found to be [0. In other words, segregation was prevailed in studied species rather than aggregation. Keywords Central Black Sea Region Á Coastal sand dunes Á Humped-back relationships (HBR) hypothesis Á Species aggregation Á Species seggregation Á Stressgradient (SGH) hypothesis & Burak Surmen

In the present study, the rare species of the city Samsun which distributed in sand dune ecosystem were investigated. The study was carried out in the localities Çobanyatağı (Terme), Sindel, Hürriyet and Costal (Çarşamba), Cernek, Sahilkent (Bafra) and Doyran (Alaçam) of Samsun sand dune. Sand dune communities were sampled from April 2010 to July 2012 by using minimal area method in 16 m 2 plots. The coastal sand dunes of Çobanyatağı, Sindel, Cernek, Sahilkent (Bafra) and Doyran (Alaçam) is consist of upper beach/driftline, primary/embryonic, main, transitional and, fixed dune zones) while the fixed zone is totally disappeared and transitional zone is significantly interrupted in the localities Costal and Hürriyet especially due to the building settlement. Rare species on each coastal dune zones in all localities were determined according to the rarity index formula. As a result, each locality was assessed independently, and it is indicated that the rarity index of 47 species is low.

No abstract

Coastal dunes are very prone to environmental changes and they are very vulnerable ecosystems. Coastal dune vegetation in the north of Turkey cover a comparatively wide area (149 km) and they include most of the characteristic coastal dune zones. However, they are threatened by disturbance factors and most significant of these are inundation and dune erosion especially in drift line. In the present study, the relationships between some chemical and physical traits and coastal dune species in characteristic dune zones were investigated in Central Black Sea Region of Turkey. Soil reaction (pH), sodium adsorption ratio (SAR), organic matter content (% OM), potassium ion (K +) concentration, bicarbonate ion (HCO 3 −) concentration and coarse and very fine sand contents were found to be the most significant abiotic factors along seashore to inland gradient in studied coastal dunes. Medium sand and OM contents were associated with main and transitional dunes, while pH and SAR were associated with drift line and embryonic dune zones.