Information and data flow analysis for forestry sector in Iran as a basic requirement for designing a forest information system (FIS)

The aim of this study was to evaluate the status of information on forest and data transfer and to identify the gaps in information and data flow in forestry sector in Iran. The study evaluated the data and information flow in three levels (control offices level, provincial offices level and organizational offices level) using the document analysis and questioning (interviews and questionnaire). It has a major outputs; identification of the gaps in information and data flow to sustainable forest management and also can be used as a prerequisite to designing a forest information system

Processes of forest products and production costs in Guilan forests, Iran

This research was conducted in the west forest of Guilan, northern Iran. Data from various harvesting methods for 20 years were collected. Results showed that, productivity rate of round wood, pulp wood and fuel wood has had an upward trend, while rate of traditional products (lumber, sawn wood, charcoal, etc.) has had a downward trend. Production cost has been investigated in this research. The results showed that, the main cost is the opportunity cost. Due to the disability of competition between the domestic wood price with the imported wood price, domestic wood industries will face serious investment difficulty in the future

Comparison of Sampling Methods Used to Evaluate Forest Soil Bulk Density

The objective of this study was to compare forest soil bulk density values obtained through conventional sampling methods such as the volumetric ring (VR: diameter 5 cm, length 10 cm) and paraffin sealed clod (PSC), with a variation of the VR, where rectangular boxes (RB) of four different dimensions were used. Sampling transects were established on a machine operating trail located in a beech (Fagus orientalis Lipsky) stand in Northern Iran. At each transect, three soil samples were collected at three different locations. Samples from different methods were spaced by a 50 cm distance to avoid direct interactions. The soil class of our study area was Combisols according to the WRB classification with a clay texture. Soil bulk density differed significantly between the three sampling methods. The lowest values were obtained with the RB (average 1.25 g cm-3), followed by the VR (average 1.40 g cm-3), and lastly the PSC (average 1.52 g cm-3). The values obtained with four variations of the RB method ranged from 1.22 to 1.28 g cm-3 and were not found significantly different. When soil bulk density was calculated after the removal of the weight and volume of roots included in the samples, the values were determined to be higher than before but with the same range of magnitude. The lowest coefficient of variation was found for RB4 (CV=2.3%), while the highest values were observed for VR and RB1 (CV=5.7%)

Optimal Forest Road Density Based on Skidding and Road Construction Costs in Iranian Caspian Forests

Information on the productivity, costs and applications of the logging system is a key component in the evaluation of management plans for the rehabilitation and utilization of Caspian forests. Skidding and road construction costs are expensive forest operations. Determining the optimum forest road network density is one of the most important factors in sustainable forest management. Logging method is an important factor to determine the optimum road network density. In this research, in order to determine the optimum road network density, skidding cost and road construction cost were calculated. Linear programming model was used in order to reduce the skidding costs and to determine the optimal forest road network density. Our aim was to determine the minimum skidding cost for Timber Jack and Clark skidders for different average skidding distance. The results showed that it is less costly if Clark skidder is used for skidding. Then the optimal road network density at this manner was 8 m/ha

Evaluation of Different Best Management Practices for Erosion Control on Machine Operating Trails

Ground-based mechanized forest operations often lead to increased runoff and soil loss on unbound forest roads and machine operating trails, which in turn can impede the technical trafficability of machines and cause negative impacts on the environment. The aim of this study was to evaluate the effectiveness of three Best Management Practice (BMP) treatments used to control erosion occurring on machine operating trails. The treatments included water bar, water bar and hardwood brush (H-brush), and water bar and softwood brush (S-brush). For a more comprehensive assessment of both brush treatments, two levels of brush thickness were tested; 0.5 m and 1.0 m. Results indicate that the most effective BMP treatments were the water bar and softwood brush followed by the water bar and hardwood brush and finally the least effective was the water bar. The average runoff rates and soil loss from the machine operating trails with the water bar treatment (52.64 l per plot, 8.49 g m-2) were higher than runoff and soil loss at the trails protected with hardwood brush (23.75 l per plot, 4.5 g m-2), and the trails protected by the hardwood brush had higher runoff and soil loss compared to trails covered by softwood brush (15.83 l per plot, 2.98 g m-2). Furthermore, results of this study showed that regardless of the treatment, the amount of runoff and soil loss decreased consistently as the thickness of the brush mat increased. Overall, erosion control techniques similar to either H-brush or S-brush that provide direct soil coverage should be used for erosion control, and final selection should be based on costs, availability of material, or landowner objectives

Green and energy-efficient methods for the production of metallic nanoparticles

In the last decade, researchers paid great attention to the concept of “Green Chemistry”, which aims at development of efficient methods for the synthesis of nanoparticles (NPs) in terms of the least possible impact on human life and environment. Generally, several reagents including precursors, reducing agents, stabilizing agents and solvents are used for the production of NPs and in some cases, energy is needed to reach the optimum temperature for reduction. Therefore, to develop a green approach, researchers had the opportunity to investigate eco-friendly reagents and new energy transfer techniques. In order to substitute the harmful reagents with green ones, researchers worked on different types of saccharides, polyols, carboxylic acids, polyoxometalates and extracts of various plants that can play the role of reducers, stabilizers or solvents. Also, there are some reports on using ultraviolet (UV), gamma and microwave irradiation that are capable of reducing and provide uniform heating. According to the literature, it is possible to use green reagents and novel energy transfer techniques for production of NPs. However, these new synthesis routes should be optimized in terms of performance, cost, product quality (shape and size distribution) and scale-up capability. This paper presents a review on most of the employed green reagents and new energy transfer techniques for the production of metallic NPs

Remote sensing-assisted mapping of quantitative attributes in Zagros open forests of Iran

The Zagros forests come as one of the most valuable ecosystems in western Iran. Therefore, accurate and up-todate information on basal area, canopy cover, and stem number per hectare of these forests are the important factors in the context of forest management and conservation. The main objective of this study was to estimate quantitative forest attributes using Landsat 8-OLI image data and Random Forest, a well-known machine learning technique. The results were shown the lowest out of bag error with the combination of 800 trees and 8 variables in each node as the optimal model parameters to classify forest canopy cover with overall accuracy and Kappa coefficient of 83% and 0.73 respectively, while those of classified mapping of basal area were 78% and 0.72, and also those of stem number per hectare were 75% and 0.69 respectively. All in all, the Random Forest classifier algorithm provided comparatively successful mapping results of quantitative attributes in Zagros open forests of Iran from Landsat 8-OLI image data

Survey of Directional Felling and Analysis of Effective Factors on Felling Error (Case Study; Iranian Caspian forests)

Economic and environmental logging is important for sustainable wood production in the Caspian forests, north of Iran. Predetermination of the skid trail network and directional felling is a usual recommended method to reduce logging impact. The aim of this study was evaluation of directional felling and finding factors effective on felling error. Totally 135 trees were selected randomly for directional felling in mountainous forest in Nav watershed in the Caspian forest. Felling error was calculated for each observation in relation to lay deviation of ground slope, tree length, tree lean, the extent of rot on stump, and tree volume using multiple regression models. Tree volume, interaction of tree volume and terrain slope, and extent of rot in the stump were the most influencing factors on felling error. Results suggest that felling workers should be enough trained for proper use of tools and equipments. The most common tools and devices for manual felling are wedge and hydraulic jack which should be provided in advance

Impact assessment of skidding extraction: Effects on physical and chemical properties of forest soils and on maple seedling growing along the skid trail

Several studies investigated soil disturbances caused on skid trails by forest logging. However, there is still a lack of knowledge about the severity and the distance of disturbances along both sides from the trails. The aims of this study were: i) to investigate the changes in physical and chemical properties of soil along the sides of skidding trails; ii) to measure the effects of soil compaction on of maple seedlings growth. Two levels of trail gradient ( < 20% and > 20 %), four levels of traffic frequency (3, 8, 15, and 30 passes) and four distance buffer strip zones (0.5 m intervals from 0 to 2 m in distance) on both sides of skid trail edges were analyzed. Each treatment included three replicate plots. In order to investigate the effect of compaction on seedlings emergence and growth, maple seeds were sown after logging. The results highlighted significant changes in physical and chemical properties of soil for each traffic frequency in the closest buffer strip (from 0 to 0.5 m from the skid trail edges). The largest changes in soil properties were identified at 0.5 m distance zones for a slope gradient > 20% after 3, 8, 15, and 30 skidding cycles. The highest changes were recorded on slope category > 20%. The higher the soil compaction the lower the germination rate, root length, and stem height of seedlings

Evaluation of Factors Affecting Water Erosion along Skid Trails (Case study; Shafarood Forest, Northern Iran)

Water erosion causes severe soil damage in northern forests of Iran which is associated with different rut depths in skid trails. The aim of this study was to assess rutting and soil displacement on skid trails to mitigate water erosion. Therefore the research was carried out in eight parcels of district No 3 of Shafarood Forest in the North of Iran. In order to evaluate the amount of erosion in skid trails, 30 lateral profiles in three slope classes (0-15, 15-25 and >25%) were randomly chosen from 10 skid trails. The amount of soil displaced and ruts were measured using lateral profile of skid trail. Then the effective factors on soil disturbances such as longitudinal slope, soil texture, crown canopy and forest floor cover were separately measured in the studied plots. The results of regression analysis showed that there were significant differences between amount of soil erosion and longitudinal slope, soil texture, crown canopy and forest floor cover. The results from Pearson test showed that there was significant correlation between amount of soil erosion and longitudinal slope of skid trails, soil texture and forest floor cover (α= 0.01 and α= 0.05), but there was no significant correlation between amount of soil erosion and crown canopy. The results of this research showed that by increasing longitudinal slope of skid trail, displaced soil volume and rutting depth increased. The sample plots in longitudinal slope class of >25% and average displaced soil volume of 5.3 m3 had maximum disturbance. Mean comparison test also showed that there were no significant differences in the displaced soil volume in the two longitudinal slope classes (0-15 and 15-25%), but with an increase in longitudinal slope (more than 25%), the average displaced soil volume increased