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ŠUMARSKI LIST 7-8/2017 str. 37     <-- 37 -->        PDF

especially information about salvage logging planning after fire, logging practices, and workforce were recorded. The study area was investigated by field reconnaissance and visual data were taken for office evaluations. Besides, forest activities which were implemented based on “Rehabilitation of Burnt Forest Areas and a Fireproof Forest Facility Project” were examined in the field.  This project, in fact, was initiated by GDF after Serik-Taşağıl forest fire and firstly implemented in this region (GDF, 2008). Salvage logging reports and extraordinary timber extraction data obtained from FEC were reorganized by using MS Excel program. One of the methodologies used and studied is the Analytic Hierarchy Process (AHP) proposed by Saaty (1980) in the early eighties. AHP significantly helps decision makers on multi-criteria and multi-alternative problems to finalize the decision process. The first step in the AHP is to develop a graphical representation of the problem in terms of a goal, criteria, and alternatives. Then, data were managed in order to be imported and run in mathematical optimization programs such as LINDO, MATLAB, WINOSB, and CPLEX. Among those, LINDO is mostly used mathematical program with key tools for analysis of stochastic and global optimizations,  linear and nonlinear optimizations, linear-integer and nonlinear-integer optimizations, and infeasible linear, integer and nonlinear models (LINDO, 2010).
2.3. Operational Planning Approach – 2.3. Pristup operativnog planiranja
Forest managers usually aim to extract fire-damaged timber from the stand in the shortest amount of time possible in order to initiate post-fire regeneration activities and to prevent deterioration of timber caused by fungus and insects. In this study, operational planning approach was implemented for removing salvage timber in a timely manner after large scale forest fires, while considering economic, environmental, and social (i.e. employment condition) constraints. For this purpose, a Post-fire Action Planning (PFAP) model was developed based on operational planning approach. Figure 4 indicates methodology of PFAP model.
In order to develop an objective function that minimizes total time spent on work stages of post-fire salvage logging operation, each work stage was evaluated separately. Thus, objective function aims to minimize total time spent on damage assessment (DA), felling (F), timber extraction (TE), hauling (H), and road construction (RC). The effects of different forest compartments (c), seasons (i.e. high density and low density seasons) (s), and alternative forest operation techniques (t), and damage assessment groups (g) were evaluated in solution process. Following equations indicates the objective function:  
DAcs    = Damage assessment time per unit area (min/ha) per hectare by group “g”, at “c”   compartment, during “s” season 
Acst       = Fire damaged area (ha) at “c” compartment during “s” season
Fcst    = Felling time per unit volume (min/m3) at “c” compartment during “s” season by using “t” forest operation technique
Vcst    = Volume of fire damaged timber (m3) at “c” compartment during “s” season by using “t” forest operation technique
TEcst     = Timber extraction time per unit volume (min/m3) at “c” compartment during “s” season by using “t” forest operation technique
Hcst       = Hauling time per unit volume (min/m3) at “c” compartment during “s” season by using “t” forest operation technique
RCcst    = Road construction time per unit length (min/m) at “c” compartment during “s” season by using “t” forest operation technique
Lcst     = Road length constructed (meters) at “c” compartment during “s” season by using “t” forest operation technique
The constraints of the mathematical model are listed below:
1)  The volume of extracted timber (TYcst) from each forest compartments is limited to extraordinary timber yield of the compartments (EXTYcst): 
 
where Wcst = 1 if damaged timbers are extracted, or it is equal to “0” otherwise
2) The volume of total extracted timber from the study area after fire is limited to total extraordinary timber yield (TEXTYcst):
 
3) Each forest compartment damaged by fire must be subject to timber extraction: