Long-term dynamics of leaf litter decemposition in Western Blacksea beach-chestnut mixed forests

The aim of this study is to determine the long-term (4-year) change of the decomposition of leaf litter in beech (Fagus orientalis Lipsky) and chestnut (Castanea sativa Mill.) forests of Düzce-Akçakoca region of Western Black Sea Region. Data about leaf litter decomposition from different elevations and aspects in beech and chestnut forests where represents the coastal part of the Black Sea, were collected in order to define the parameters explain these variations. The sampling areas were chosen in 4 different elevations between 420-1050 m (Y1: 450-600 m, Y2: 600-750 m, Y3: 750-900 m, Y4: 900-1050 m) within two aspects, east and west. The soil pH varies among 4,5-6,5 and shows predominantly loam and clay loam properties and is among the Inceptisol soils according to the USDA soil classification system. The crown closure in the forests is % 75 and above. Three sampling plots at each elevation stage were selected. In order to determine the leaf-litter decomposition rate, litterbags containing leaf-litter samples collected with litter-traps placed on mineral soil were collected in an area of 20x20=400 m2 and carried to laboratory to calculate mass loss. According to this, % 30 and % 40 of the total mass of chestnut and beech leaves were found to be left behind at the end of 4th year, respectively. In the same period, there was a difference between eastern and western aspects only in beech stands, while there was no for chestnut stands. While the percentage of mass remaining at the end of the fourth year for the beech leaves showed a statistically significant difference between the elevation stages, such a situation could not be detected in the chestnut leaves. At the end of the fourth year, the carbon and nitrogen ratios did not differ between species. All these data show that decomposition can vary between species and also among different aspects and elevations. Therefore, it can be seen that the decomposition can vary depending on the chemical properties of the organic material and also depending on the environmental conditions. This can be used as an effective decision support mechanism in long-term decisions to be taken in the management processes of similar ecosystems.