Effect of logging wounds on diameter growth of beech (Fagus orientalis Lipsky) trees following selection cutting in Caspian forests of Iran

Background Logging damage to residual trees during selection cutting may lead to serious economic losses in terms of both timber quality and diameter growth reduction. In this study, we investigated the effect of logging operations on residual tree damage and the consequence of injuries on diameter growth in an uneven-aged mixed forest dominated by beech (Fagus orientalis Lipsky)

Qualitative evaluation and optimization of forest road network to minimize total costs and environmental impacts

An efficient and low-cost transportation network is necessary for sustainable management. Roading and log skidding are the most expensive and destructive operations in forest environment, unless carefully planned and evaluated. A transportation network has to be assessed and optimized to minimize the total cost of road construction and its environmental impact. The aim of this study was determining the optimum forest road network density, and evaluating the quantity and quality of the existing forest road network. In order to determine the optimum forest road network density, skidding cost, road construction and maintenance costs, and harvesting volume in each compartment were considered. Then optimum skidding distance was calculated with regard to opti­mum road density and total correction factors. The relative openness and efficiency coefficient of the existing forest road network were determined for the calculated optimum skidding distance, using ArcGIS. The results showed that the optimum road density, relative openness and road network efficiency coefficient were 21.5 m ha-1, 90% and 32%, respectively. As a result, when the quality of a forest road network has to be evaluated, road network efficiency coefficient is more efficient than relative openness, that per se cannot be considered as an appropriate indicator

A GIS-MCDM-based road network planning for tourism development and management in Arasbaran forest, Iran

It is very important for managers to plan a road network that meets all the requirements for tourism development and management. The aim of this study was to evaluate and modify an existing road network for tourism purposes in the Arasbaran protected area. First, the map layers of effective criteria were prepared in GIS and were standardized by a fuzzy logic approach and finally combined considering their relative importance weights obtained through pair-wise comparison technique. A suitability map was then acquired. After that, 14 different scenarios of road network were designed to access the recreational area using PEGGER extension in ArcView. Then, they were evaluated in terms of technical, environmental, and socio-economic criteria to achieve the optimal-designed road network. Moreover, the existing road network was modified according to the optimal-designed road scenario. Finally, a modified version of the existing road network was proposed for tourism development and management in the Arasbaran region. Regarding the results, the slope criterion with a value of 0.289 was identified as the most important factor in providing a suitability map for road planning. The seventh scenario, with a road density of 3.34 m ha−1 and accessibility (hard) of 64.68%, was chosen as the optimal option to modify the existing road network due to the best performances in terms of minimum costs and environmental impacts on the basis of the highest value per unit length (72.26). According to the assessments and chi-square test comparison, the optimal-designed road network and the proposed road network were identified as better alternatives compared to the existing road. Based on this work, it can be concluded that the combination of GIS-MCDM approaches can properly assist in tourism planning and management

Forest road planning to improve tourism accessibility: a comparison of different methods applied in a real case study

Forest road planning with the available tools, e.g. PEGGER and GIS, still requires a lot of time of an expert, and the designed roads are not guaranteed to be efficient in terms of the cost or suitability of the road. In this article, we propose a novel Genetic Algorithm (GA) based method for forest road planning. To do so, each road is represented as a sequence of fixed and variable (control) points. A novel objective (fitness) function is defined based on the length, gradient, and suitability of the roads (individuals). The proposed algorithm is applied to the Arasbaran forest area and the resulted roads are compared with PEGGER-designed roads regarding length, Bachmund index, accessibility, and suitability. The results clearly show the power of the proposed GA algorithm in reducing computation time, road construction costs, and environmental impacts compared to the common road planning approaches