DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 7-8/2017 str. 34 <-- 34 --> PDF |
et al., 2004). Besides, fire damaged trees become more vulnerable to deterioration agents such as insects and fungus (Akay et al., 2007). Forest fires result in important amount of economic value loss on forest products and this loss tends to increase as they stay longer in the forests before salvage logging operation starts. Therefore, in order to reduce these negative effects after forest fires, post-fire salvage logging operations should start immediately to extract fire damaged timber and make the site ready for regeneration activities. The time spent on planning and implementation of salvage logging operations is mainly limited by the urgency of necessary revegetation activities at the site, value loss of forest products as time passes after fire, and expected attacking time of deterioration agents. To minimize the time spent on salvage logging operations especially after large scale forest fires, Post-fire Action Planning (PFAP) model can be used to overcome these types of complex problems, while considering various economic and environmental constraints. Operational planning approach and decision support systems are common methods to efficiently develop such models for optimal usage of forest products. In the previous studies, operational planning approaches and decision support systems have been widely used in forest operation planning studies. Eker (2004) developed an operational planning method in which mathematical model was developed by using linear programming and integer programming techniques to plan forest harvesting activities. In another study, Akay (2009) used dynamic programming based stem-level optimum bucking algorithm to investigate the effects of forest harvesting techniques (manual skidding vs. ground based mechanized skidding) on optimum bucking method by considering the maximum allowable log lengths. Operational planning approach and decision support systems have been also used in post-fire salvage logging operation studies. Akay et al. (2006) developed a computer programming based model to evaluate productivity and cost of helicopter logging system for extraction of fire damaged trees after forest fire. The decision variables in the model included tree diameters, log position within the tree stem, yarding distance, and time since tree death. They stated that salvage logging operation should be planned and performed promptly to recover the maximum economic value of fire damaged trees. In order to determine the management and strategies in forestry, decision support systems are often used in previous studies. Reynolds (2005) used simulation for small private holdings to cooperative management across multiple ownerships. Zeng et al. (2007) used simulation method assessing the short- term and long-term risk of wind damage in boreal forests (i.e. stand and regional level). Lineer Programming and Mixed Integer Programming were used for strategic and tactical forest planning applications by Andersson and Erikssonn (2007). In another example, fuzzy set theory was employed for effective fire management planning (Kaloudis et al. (2008). Drosos et al. (2008) conducted a study where post-fire data were evaluated by using geoinformatic models. They organized post-fire salvage logging operations by generating optimized road network based on Digital Terrain Model. Karantzidis et al. (2008) analyzed environmental effects of logging operations after forest fires. They stated that post-fire salvage logging operations cause reduced impact on forest ecosystem especially during skidding activities which are more suitable with environmental conditions. Eker and Çoban (2009) introduced general framework of logging and transportation planning model for post-fire forest operations. They also described system structures and capabilities of the model. In a follow up study, they tested effectiveness of new roads and existence roads during post-fire forest operations (Çoban ve Eker, 2010). Öztürk et al. (2011) conducted a study where performances of modern harvesting equipment were evaluated during post-fire salvage logging operations. It was reported that using modern equipment potentially improves working conditions and increases productivity comparing with traditional logging methods. In this study, A Post-fire Action Planning (PFAP) model was developed to determine optimum operation techniques that minimize the time spent on extraction of salvage timber and reduce environmental impact after forest fires. Multi-criteria analysis was used to evaluate many work stages of salvage logging operations, while considering ecological, economic, and social constraints. Then, the model was implemented in Taºağıl Forest Enterprise Chiefs (FEC) of Antalya Forest Regional Directorate in Mediterranean region of Turkey. 2. Material and Methods 2. Materijali I Metode 2.1. Study Area – 2.1. Podruèje mjesto istrazivanja In order to select the most appropriate study area, large forest fire incidents taken place in Turkey were evaluated within the archive of General Directorate of Forestry (GDF). Serik-Taºağıl fire, in which 15795 ha forested area was burned in 2008, was selected as the study case (Figure 1). This fire was the second largest forest fire in the history of Turkish Forestry and caused serious damages on four FECs including Akbaº, Karabük, Sağırın, and Taºağıl in the city of Antalya (Figure 2). The forests are sensitivity to fire at the first degree level and the dominant tree species was Brutian pine (Pinus brutia T.) in the region. The forest stand characteristics in these FECs are listed in Table 1. |