The effects of stand establishment features and climate change on bay (Laurus nobilis L.) production in bartin region within the scope of sustainable forestry

Within the scope of sustainable forestry, there are two main objectives in this study, which is to determine the stand characteristics of Laurel (Laurus nobilis L.), which spreads naturally within the borders of Bartın Forest Sub-District Directorate, and to reveal its changes due to climate change. The first aim is to determine the most suitable stand establishment by associating it with the factors affecting the productivity and quality of laurel under different stand establishments and to prepare basic data for silvicultural practices to be carried out. The second aim is to determine the effects of global climate change on the development, dynamics and natural boundaries of the bay laurel and to provide some basic and applied information on the subject as a preliminary evaluation for practitioners and future academic studies. The study was carried out on Çmc3 stands in Esenpınarı village, Knbc3 in Kaman village and Çzbc2 stands in Topluca village, within the borders of Bartın Forest Sub-District Directorate affiliated to Bartın Forestry Operations Directorate. In the study, measurements were made in 27 sampling stands from a total of 9 compartments, with 3 replications. In addition, using WorldClim data, SSPs 245 and SSPs 585 scenarios of the research area for the years 2060 and 2100 were studied and annual average temperature and annual average precipitation scenario maps for the research area for the years 2060 and 2100 were obtained. Using these maps, it was revealed how the laurel might spread in the future. According to the findings obtained in the study regarding stand establishments; Of the sampling stands, 23 are equal-aged establishments, 4 are differently-aged establishments, 12 are mixed stands, 15 are pure stands, 20 are single-layered stands, 7 are two-layered stands, 2 stands with canopy class 1, 18 stands with canopy class 2, 7 stands with canopy class 3 were determined. In the study, separate statistical analyzes were made according to stand type and canopy and different statistical relationships were revealed. From here, according to the statistical analyzes performed in all sampling stands to determine the effects of stand type and canopy, which are the basic components of stand establishment, on the development and change of laurel; 1- The interaction between the number of laurel patch and stand type and stand canopy was significant. 2- The number of shoots and stand type were significant. Accordingly, while the number of shoots was low in areas where beech formed the primary stand, the number of shoots was found to be high in areas where red pine and maritime pine formed the primary stands. 3-The number of resting bud and stand type were significant. Accordingly, while the number of resting bud was low in areas where beech formed the primary stand, the number of resting bud was found to be high in areas where red pine and maritime pine formed the primary stands. 4- Leaf width and stand type were found to be significant. Accordingly, while the leaf width was large in areas where beech formed the primary stand, leaf width was found to be small in areas where red pine and maritime pine formed the primary stand. As a result of the analyzes made based on global climate scenarios in the study, it was revealed that laurel was affected by climate change. In this context, within the scope of the data collected from the digital maps of the years 2060 and 2100 regarding the temperature and precipitation variables obtained in the region containing an elevation zone of approximately 500 m, especially according to the Lauretum, Lauretum-Castanetum and Castanetum zones, the distribution area of the laurel is today a total of 166509.09. ha, and it has been determined that this area will decrease to 157075.98 ha in 2060 and to 146882.72 ha in 2100 according to the SSPs 245 climate change scenario. On the other hand, according to the SSPs 585 climate change scenario using the same indexes, it has been revealed that the semi-humid and humid regions and growing environments containing suitable ecological conditions for the natural growth of laurel have decreased to 106804.02 ha in 2060 and to 11046.47 ha in 2100. It has been revealed that natural structures must be protected first in order to maintain the population of the laurel in the region and increase its productivity within the scope of sustainable forestry. In this context, appropriate silvicultural interventions should be made to meet the desired qualities and quantities in laurel production. In addition, other non-wood forest products, especially laurel, need to be protected by in-situ and ex-situ methods.