Wetland loss in Turkey over a hundred years: implications for conservation and management

Abstract

The aims of this study are to provide a complete inventory of wetlands in Turkey including their past status (1910-1930) in comparison to the present time (2014), and also recommendations for conservation and management. The types of wetlands and their area sizes were determined by using cartographical maps of 1/200,000 in scale made between 1910s and 1920s vs. 2006 CORINE Land Cover data, which was updated with Landsat 8 satellite images in 2014. Long term rainfall pattern for these wetlands during these two periods were determined using the North Atlantic Oscillation index (NAO). A hundred years ago, the total number of natural wetlands was 1299 with a total surface area of 1,376,505 hectares (ha). In 2014, the total number of natural wetlands had decreased to 900, with a total surface area of 1,085,936 ha, so that 21.2% of the original wetlands were lost (291,339 ha). NAO was negatively correlated (p<0.01) with the mean annual amount of precipitation in Turkey, but statistically explained 14% of the variability in the mean amount of annual rainfall. It can be concluded that the observed changes in the number of wetlands and their relative sizes cannot be attributed directly to changes in climate. Wetland drainage is largely responsible for observed wetland losses but regional changes in precipitation regimes partially contributed to this loss. Urgent conservation and restoration of wetlands are recommended to avoid further loss of wetlands in Turkey.