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Öğe Evolution of Modern Forest Management Planning in the Republic of Turkey(Soc Amer Foresters, 2013) Zengin, Hayati; Yeşil, Ahmet; Asan, Ünal; Bettinger, Pete; Cieszewski, Chris; Siry, Jacek P.The Republic of Turkey has a long history of forest management that has undergone considerable change over the last 100 years due to political, economic, and social issues. For the most part, state-owned forestlands (the largest forest owner category) have been managed under plans arising from a conventional process that used classic techniques to regulate activities and allowable harvest levels. However, over the last 35 years, four different types of forest management plans have been developed (conventional and model) and applied universally or to a specific region of the country. Today, a single type of planning process is used, which emphasizes ecological and environmental conditions, multiple uses of the landscape, and social concerns. Although management and planning are evolving, implementation is challenged by a continued focus on wood production rather than on other concerns, a lack of skilled personnel and qualified decisionmakers, and other societal conflicts.Öğe Forest management issues of the southern United States and comparisons with Turkey(Tubitak Scientific & Technical Research Council Turkey, 2013) Bettinger, Pete; Siry, Jacek; Cieszewski, Chris; Merry, Krista L.; Zengin, Hayati; Yeşil, AhmetMost of the forest area in the southern United States has been cleared, regrown, purchased, and sold several times over the last 200 years, and forest management practices generally focus on wood production. Agricultural expansion, use, and the abandonment of land have been the major forces behind land use change, and now human population expansion is a major issue. The land tenure system of the United States has allowed individuals and companies to acquire, use, and sell land since the time of European colonization; thus, private ownership of land dominates the southern region. However, new private, corporate, nonindustrial entities have arisen in the last 20 years, mainly as a result of tax policies and changes in industrial business organizations. While in Turkey planning systems are centralized, these systems vary by landowner group in the southern United States. They range from those that are relatively absent (nonindustrial private landowners) to those that are very formal (national forests). The management of forests in the southern United States is also guided by a number of federal, state, and local policies rather than a single enterprise plan, and these policies affect the direction of both public and private forest management. Specifically with regard to public land, the mission and objectives of forestry are similar to those in Turkey, except when considering the needs of local citizens, which has been given greater emphasis in Turkish forest management and planning.Öğe MODELING HARVEST SCHEDULING IN MULTIFUNCTIONAL PLANNING OF FORESTS FOR LONGTERM WATER YIELD OPTIMIZATION(Wiley-Blackwell, 2015) Zengin, Hayati; Asan, Ünal; Destan, Sinan; Ünal, Murat Engin; Yeşil, Ahmet; Bettinger, Pete; Değermenci, Ahmet SalihIn this study, wood production and hydrologic functions of forests were accommodated within a planning procedure for separate working circles (areas dedicated to certain forest functions) that were delineated according to an Ecosystem-Based Functional Planning approach. Mixed integer goal programming was used as the optimization technique. The timing and scheduling of a maintenance cutting (partial harvest) was the decision variable in the modeling effort, and an original formulation was developed as a multiobjective planning procedure. Four sample planning strategies were developed and model outputs were evaluated according to these strategies. Spatial characteristics of stands were considered, and used to prohibit the regeneration of adjacent stands during the same time period. Because of the positive relationship between qualified water production and standing timber volume in the forest, the model attempts to maximize qualified water production levels by increasing standing volume stocks in the forest through the delay of regeneration activities.Öğe Spatial harvest scheduling for oak coppices conversion into high forest involving wood production management(Univ Austral Chile, Fac Ciencias Forestales, 2018) Çağlayan, İnci; Yeşil, Ahmet; Zengin, Hayati; Ünal, Murat EnginOak forests in northern Turkey have been largely managed as coppice. Nevertheless, in parallel with the decrease in demand of firewood and charcoal, the coppices, having no social demand or regional pressure, have been converted into high forests since 2006. Because of this new regulation, a potential need has arisen to schedule forest harvests activities, which is based on the natural regeneration in those forests. The objective of this research was to develop a spatial forest planning process to schedule new harvests activities in coppices conversion into high forests. In the proposed study, four different planning strategies were used to estimate the most appropriate period for regeneration. Constraints essentially included those related to the need for an even flow, adjacency and to adhere to a maximum opening size. The scheduling process employed a mixed integer linear programming to schedule harvest activities and to maximize amount of harvested volume in planning horizon. The process was employed for the development of 100-year planning horizon for a Sergen forest range in the Thrace region of northern Turkey that was 3,448.8 ha in size. For obtaining various spatial data and solving the mathematical model, ArcMap and GAMS programs were used, respectively. Results showed that the value of the objective function in the case study forests could significantly increase when there is no constraint under the proposed harvesting plans in strategy 1 (3,652,072.8 m(3)). The amounts of wood production were similar in strategy 2 (3,547,613.5 m(3)) and strategy 4 (3,547,393.5 m(3)).
