Uzay Karahalil

Estimation of Crown Closure and Tree Density Using Landsat TM Satellite Images in Mixed Forest Stands

The objective of this study was to investigate the relationship between crown closure and tree density in mixed forest stands using Landsat Thematic Mapper (TM) reflectance values (TM 1- TM 5 and TM 7) and six vegetation indices (SR, DVI, SAVI, NDVI, TVI and NLI). In this study, multiple regression analysis was used to estimate the relationships between the crown closure and tree density (number of tree stems per hectare) using reflectance values and vegetation indices (VIs). The results demonstrated that the model that used SR and DVI had the best performances in terms of crown closure (R2 = 0.674) and the model that used the DVI and SAVI had the best performances in terms of tree density (R2 = 0.702). The regression model that used TM 1, TM 3 together with TM 4 showed the performances of the crown closure (R2 = 0.610) and the regression model that used TM 1 showed the performances of the tree density (0.613). Results obtained from this research show that vegetation indices (VIs) were a better predictor of crown closure and tree density than other TM bands.

The effects of land cover changes on forest carbon storage in 40 years: a case study in Turkey

In this study, forest biomass carbon storage changes were estimated for a case study area of Caykara planning unit based on forest inventory for the years 1971 and 2010 using tree species dependent biomass expansion factors. The outputs were handled in the context of forest dynamics represented by temporal and spatial changes of land cover. Quantitative evidence showed that there were drastic changes of carbon storage in above and below ground forest ecosystems from 2.34 Tg carbon to 3.91 Tg carbon between two periods. Carbon sequestration rate was 1.37 Mg carbon yr–1 ha–1 for living biomass due mainly to the increase of forest area and growing stock and its quality. On the other hand, such a rate of increase in carbon storage was not influenced negatively by an almost tripling in the total number of patches from 406 to 1,445 in the same period.

Harvest scheduling and operational planning for mountainous areas: A case study for Ikisu planning unit

Harvest scheduling has emerged as time consuming and difficult activity especially when includes operation plans in the absence of decision support systems. In this study, the level of allowable cut and timber extraction system for every stand was determined for spruce management unit of a mountainous İkisu planning unit in Turkey using linear programming model designed for 50 year planning horizon. First, different considerations such as maximization of timber cut with non-exceeding more than a certain distance between the centroids of compartments and the nearest forest roads were taken into account in determining the level of harvest. Approximately 68,728 m3 annual allowable cut was determined for the first period of planning horizon. Then, six different timber extraction systems were incorporated during the designation of timber extraction method for the first 10 year period of the planning horizon. These are man power, animal power, skidder, small size cable crane, medium size cable crane and sledge yarder. Different factors such as transport direction, slope, distance to forest road, efficiency or cost were also taken into account in decision making. Various planning strategies were developed, including maximization of profit, minimization of timber loss, under time restrictions and solved with LINDO software. One of the strategies was selected based on the availability of the machineries, legal arrangements, staff and economic conditions of the forest enterprise. According to the selected strategy (STR2), with the maximal total profit from timber production including time constraints less than 2,000 hours for cable cranes and sledge yarders, 6,365,205 € would be earned, 19,055 hours would be spent, and 1,697.8 m3 timber would be lost, while 91.77 damage would occur. As a result this determination could bring us benefits especially in environmental awareness, time, labor and money when compared to the classical approaches. KEy wORdS: forest management, harvest scheduling, operational planning, timber extraction systems, İkisu planning unit, Blacksea region HARvEST SCHEdULING ANd OPERATIONAL PLANNING FOR MOUNTAINOUS AREAS: A CASE STUdy FOR IKISU PLANNING UNIT PLANIRANJE SJEČE I OPERATIVNO PLANIRANJE ZA PLANINSKA PODRUČJA: STUDIJA SLUČAJA PLANSKE jEDINICE IKISU Erhan ÇALIŞKAN* Uzay KARAHALI . L