The use of black locust (Robinia pseudoacacia L.) in restoration practices of degraded forest lands located in Duzce province of Western Black Sea region

This study was conducted in five-year-old black locust plantations established in degraded forestland in northern Black-Sea region of Turkey. In 2009, all woody and herbaceous vegetation were scarified with a bulldozer equipped with a brush rake in a degraded forestlands located in three different sites in northern part of Duzce valley. The plantation site was ripped to 80-90 cm soil depth with the same bulldozer. Then 2 +0 bare root black locust seedlings were planted in late fall of 2009 and early 2010. Following four year after establishment manual vegetation control were applied in all experimental sites. In July and August 2015 30 seedlings from each site were uprooted for analysis. Soil samples were taken around each sampled trees from three directions and four distance (0, 50, 100 and 200 cm) at 30 cm soil depth. Soil samples were analyzed for pH, bulk density, total N and C. Trees growing on northwestern aspect had accumulated about 64 % more biomass then that on southeastern site in five years. Soil C (2.4 %) and N (0.15 %) rate were similar in 200 cm periphery of the tree base. Data indicate that black locust can be used as part of restoration practices in degraded forestlands as a N-fixing species to facilitate the site for the later species.