فصلنامه پژوهشهای علوم و فناوری چوب و جنگل
سال بیست و نهم شماره 4 (زمستان 1401)

despite occupying a relatively small space, the border forests have the potential to accumulate more and faster carbon, are centers of biodiversity and provide many valuable ecosystem services. Riverine forests also affect plant biodiversity patterns, soil characteristics, and habitat quality. Despite having high environmental and conservation values, the riverine forests have been paid less attention as forest covers, and most of the studies related to the distribution pattern of species and characteristics of the animal community It was their soil. The aim of this research was to investigated the effect of different types of land use on the physical, chemical and carbon deposition characteristics of the soil along the Karkhe River. In this research, the effect of natural forest uses, forestry, agriculture and barren lands on the banks of the Karkheh River on some physical and chemical characteristics and soil carbon deposition was done. Thus, by random method, 30 points were selected in each field and soil samples were taken from a depth of 0-20 cm in the center of each plot. The characteristics of moisture percentage, texture, specific gravity, pH, electrical conductivity, organic carbon, total nitrogen, absorbable potassium and phosphorus, and calcium carbonate were calculated in the measuring laboratory and the amount of carbon deposition. Data were analyzed using one-way analysis of variance (ANOVA) and SNK mean comparison test. All statistical analyzes were performed using SAS 9 software. The results showed that agricultural use with 18.45% clay, natural forest and agricultural use with 46.29 and 43.92% silt, respectively, and forestry and barren land use with 60.47 and 56.86% sand, respectively. They showed a significant difference. Apparent specific mass increased during forest use change. The highest value of electrical conductivity with 3.17 decisiemens/meter was observed in barren lands, which had an increase of 71.35% compared to the natural forest. In agricultural use, absorbable potassium reached the lowest level with a decrease of 62.04% compared to the natural forest. According to the results, the change of use has a significant and decreasing effect on the amount of carbon sequestration, so that the natural forest has the highest amount of carbon sequestration with 63.37 tons per hectare, and the lowest carbon storage related to agricultural use with 41.53 tons. It was per hectare. In general, the forests along the river have more quality and soil carbon deposition, and the change of land use causes damage to these habitats. Investigating carbon sequestration in coastal ecosystems may help determine baseline conditions and can be used to strengthen restoration plans or address the impact of climate change on carbon stocks in these areas.

Quercus brantii L. is classified as vulnerable species that mostly spreaded out in the middle and southern Zagros as pure stand. Due to the elimination of natural regeneration in Zagros oak forest by overgrazing, fruit picking by human, forest decline, and habitat distruction, different researches were carried out to address natural regeneration problem. Yet, lack of regeneration in these forests still exist. Therefore, in this research we examined some simple approaches based on soil moisture preservation and implementation to find out a practical protocol to establish oak regeneration.In our country, also due to intense exploitation and destruction, forest areas are not in a proper condition. Zagros forest is one of our forest resources that turned to the disturbed forest by over grazing, increasing demand for agricultural land, and population growth is Zagros forest. Due to the high rate of oak tree dieback in the Zagros forest and its specific role in soil and water protection, the rehabilitation of these forests is necessary. The objective of this study is to determine the best method for restoration of Quercus brantii L. forests by sowing seed. this study was conducted in is Alamdar Strait in Behbahan. To this Oak seeds with five replications were planted during the winter in different treatments including by rocks, under oak tree canopy, open ground with super absorbent, open space, and curved pits in different slope, altitudes, and geographical directions. Seeds were washed by tap water to remove soil and other particles. After that they were stilled by 70 percent ethanol and placed in the distilled water 48 hours prior to plant for absorbing water. At the end of the growing season survival rate and height of the seedling was measured and their correlation with environmental factor determined. The results indicated that 25.24 percent of the seeds were able to survive the harsh environmental conditions to the end of growing season (end of the summer). Super absorbent treatment has the highest germination rate (82%) and the lowest survival rate of the seedling (6%). While rocks treatment had the least and highest germination (38%) and survival rates (31%) respectively. The west facing slope has the highest germination (77%) but at the end of the season only 29 percent of the seedling remains alive. Although, the north facing slope 71.4 percent of seed start growing but only 31 percent of the remain alive at the end of the summer. On the other hand the lowest germination (50%) and survival (14%) rates belonged to the seed planted on the ridge. The results also showed that the slope and altitude did not affect the survival of seedlings in the present study. The highest seedlings height was recorded for seedling that growth under canopy tree, while the lowest recorded for the curved pits. In conclusion direct oak seed sowing in the natural habitat provided reasonable results for rehabilitation of Zagros oak forest. Using the result of the present study in different treatment would help to gain better results in survival and growth of direct oak seed sowing.

Vaccinium arctostaphylos L. is a forest shrub that has a great role in the formation, evolution, and improvement of the beech forest stands structure. Currently, the irregular collection and harvesting of the fruit of this species (due to its medicinal properties and high economic value) even before the fruit fully ripens in the study area, has endangered the existence of this species. Vaccinium arctostaphylos is a recalcitrant plant and therefore its propagation by conventional asexual methods is almost impossible. The aim of this research is to determine the effect of auxin and inoculation of growth promoting rhizobacteria on callus formation, root formation and growth traits cuttings.

The semi hardwood cuttings of V. arctostaphylos were collected at the end of August from the natural habitat of this species (Soha forest) located in the south-east of Ardabil Fandoghlou Forest. For surface sterilization cuttings were washed with water and 2% Benomyl fungicide solution for 15 minutes. In order to stimulate root induction, the bottom of the cuttings was scratched with a sharp knife to a length of one centimeter and a depth of approximately 2 mm. Cuttings were treated with concentrations of 0, 500, 1000, 2000, 3000 and 4000 mg/ L of Indole -3-butyric acid and then were inoculated with two bacteria including Pseudomonas putida STRAIN 169 and Enterobacter cloacae STRAIN 3, alone and together. Cuttings were planted in perlite - sand medium and then they were kept in a mist system-equipped greenhouse. After 90 days from planting, the percentage of callus formation, root formation, number of roots, root length, root dry weight, root volume, leaf area, and seedlings height were recorded.

In the control cuttings (without the application of hormones and bacteria) and the cuttings treated with 500 mg L-1 of IBA with and without P. putida and E. cloacae were treated, callus and root formation were not performed. The highest callus formation (50.20 %), root formation (41.10 %), root number (3.22), root length (3.55 cm), root dry weight (0.355 g), root volume (0.358 cm3), leaf area (8.88 cm2) and height cutting (14.07 cm) was observed in cuttings that treated by Indole -3-butyric acid 3000 mg/L and inoculated with both P. putida and E. cloacae.

The present study showed that V. arctostaphylos is one of the recalcitrant species, then, for more succeed in cuttings root induction, it is suggested that semi-woody cuttings should be collected in August and cuttings should be treated by a concentration of 3000 mg/L of Indole -3-butyric acid along with inoculation of both P. putida and E. cloacae bacteria.

Soil respiration is carbon dioxide emission from soil surface which controls the primary carbon cycle in ecosystems. Recently, soil respiration has become an important ecological process in the global carbon balance and has an important impact on global climate change. Measuring soil respiration is important for quantifying the CO2 flux from soils to the atmosphere. The aim of this study is to compare the soil respiration rate at different hours of the day between five forest types (Pure Quercus infectoria) (Quercus infectoria-Quercus libani) (Pure Quercus libani) (Quercus libani- Quercus brantii- Quercus infectoria) (Quercus libani- Quercus infectoria) in the four seasons of the year (spring, summer, autumn, and winter) and to identify the effect of environmental factors (temperature and moisture) that cause changes in soil respiration rate were analyzed by using different models. Also, the correlation between respiration and soil chemical properties was evaluated.

The five dominant forest types of the region were selected after forest walking and review of resources, and samples of 20 x 20 square meters were selected in each types of plot (so that it is representative of the desired types). In order to measure soil respiration, 8 PVC pipes with specific size and diameter were installed at a depth of 5 cm in the selected sample piece and measured using Anderson's method at different hours of the day. Soil temperature and moisture were recorded with a thermometer and a TDR device, respectively, simultaneously with the measurement of soil respiration. In order to conduct chemical tests, 5 soil samples from each type were taken in the growing season and transferred to the laboratory.

The highest amount of soil respiration during the day was observed at 14:00 in the afternoon, also the Pure Libani type showed the highest rate of soil respiration with an average

Forests are subject to a variety of disturbances that adversely affect their health. There are a number of disturbances that cause trees to become weak and dry in the long run. One of them is the stress caused by burning leaves, which typically takes place during very hot summers. The identifying and monitoring of the expansion of its level is therefore very important. As one of the important information sources, remote sensing data can be used to identify it. It is possible to capture UAV images quickly and at desired times, but they have limitations such as the captured surface and the sensor's spectral range. In identifying and preparing a map of leaf burns, tree crowns, and other damages, the combined use of UAV images and satellite images with a high resolution can be helpful. The purpose of this research is to investigate and identify leaf burn of the canopy of trees using UAV images in a part of Deland Forest Park in Golestan province and combining it with Sentinel 2 images to prepare a classification map of the percentage of leaf burn in the tree canopy of the area in a wider area.

RGB UAV images were taken in Deland Forest Park and processed appropriately. Also, Sentinel 2 images were prepared and analyzed geometrically and radiometrically. Ground truth of trees with leaf burn and healthy trees was done in September 1400 selectively and with high precision differential global positioning device. The support vector machine algorithm was used to classify UAV images into three categories: trees with leaf burn, healthy trees, and clear trees. The classification of the main UAV images along with vegetation indices obtained from UAV spectral bands and with selected spectral indices was also repeated. Finally, the prepared maps were evaluated for accuracy. In the second step, for preparing a map of the classes of leaf burn percentage of the canopy cover on a wider level and in the whole park, using the image of Sentinel 2, based on the classified map of the UAV, which has the highest accuracy, as a training example in the regression model of the random forest and calibration. Finally, a map of leaf burn intensity classes of the entire Deland Forest Park area was prepared using the prepared model.

UAV image classification results indicated that UAV visible spectrum bands are able to distinguish healthy trees from trees with leaf burn with an accuracy of 89.62% and a Kappa coefficient of 0.84 for the classification of UAV images. By combining the main bands and 9 vegetation indices, the results of the research decreased slightly (overall accuracy 87.40% and kappa coefficient 0.81); however, when the main UAV bands were combined with the best vegetation indices (EGMRI, EGI and

The functions of human resource management include all the tasks that human resource management applies to the administration of its human resources. These functions may be presented in one or all areas of human resources. Considering the gradual evolution and expansion of the role of human resources management over time, experts have listed several functions for it. Due to the high dependence on the import of raw materials, the wood-based panels industries in Iran are less competitive with foreign products. Therefore, paying attention to production factors and raising productivity, especially through human resource management, can help improve the situation. Focused technology is one of the effective features of human resource management in this industry. The aim of the present research is to investigate the current situation of human resources management with emphasis on core technology and to identify the factors affecting it in the wood-based panels industries of Golestan province.

The research method is a descriptive survey. The statistical population of the studied managers and supervisors working in the wood-based panels industries of Golestan province is 37 people and the whole number sampling method was used. A questionnaire tool was used to collect the research data, the human resource management questionnaire includes seven dimensions of recruitment, selection, training, payment, reward, performance evaluation and work relations and 73 questions, and the core technology questionnaire also includes two dimensions of diversity. The task and analysability of the task and 17 questions are on a five-point Likert scale. In order to confirm the reliability and validity of the data collection tool, Cronbach's alpha and experts' opinions were used.

The results showed that the core technology has an effect on all the components of the human resource management system in the wood-based panels industries and there is a significant and positive relationship between human resource management and core technology in the wood-based panels factories of Golestan province (at the level of 95%) that the coefficient Its correlation is equal to 0.346. Descriptive examination of core technology scores showed that the average score of task versatility is 3.27 and the average score of task analysability is 3.53.

Core technology is effective in promoting human resources management, the effect of its task diversification is mostly seen in the dimensions of recruitment, selection, training and payment of human resources management, and the effect of task analyzability is seen more in the evaluation of the performance and work relations of human resources management. It can be based on Perrow's typology, engineering technology was determined as the core technology type in Golestan province's wood-based panels factories.

Bio-nanocomposites are a group of polymer nanocomposites constructed from the combination of biodegradable polymers and inorganic solids, in which at least one of their dimensions is in the nanometer range. Aerogels are materials with 3D porous interconnected structures, consisting of various polymer components. Regarding their spectacular features such as high specific surface, high porosity, and very low density, aerogels have interesting and broad potential applications in various sciences. In this research, biocompatible nanocomposite aerogels are produced from non-toxic, sustainable, and renewable materials, which are mostly by-products of the dairy industry and agricultural wastes. These nanocomposite aerogels contain large amounts of polysaccharides and proteins. These aerogels have properties of non-toxic nature, renewability, and biodegradability and can be broadly applied in various fields.

This study prepared several nanocomposite aerogels composed of various cellulose nanofibrils, chitosan, and protein nanofibrils using the freeze-drying method. The obtained aerogels were evaluated via multiple techniques to verify their components and evaluate their compatibilities. Consequently, an anionic dye was chosen as a model dye to investigate the efficiency of these aerogels in removing azo dye from water.

Ultralight (15 mg cm-3) and highly porous (98.91%) aerogels were produced. Cellulose nanofibers reinforced the structure and chitosan and protein nanofibrils added extra functional groups to the aerogel. The results obtained from the evaluation of Thioflavin-T confirmed the presence of protein nanofibrils (PNF) in composition. Overall, by reducing the cellulose fraction and increasing the protein proportion, the stability of hybrid aerogels of cellulose nanofibers/chitosan decreases up to 90% in a wet state. In contrast, the wet strength of composite aerogel containing cellulose nanofiber/chitosan/protein increased, even though the protein fraction was at its highest value, and these aerogels revealed the highest efficiency in removing anionic dye from water as well.

The results of this research study show that adding natural fillers such as cellulose nanofibers has a striking effect on promoting the mechanical stability of composite aerogels. The highly porous structure of three-component aerogel consists of optimum fractions of cellulose nanofibrils, chitosan, and protein nanofibrils perfectly prepared via establishing ionic and hydrogen bonds after the drying process in freeze-drying. Comparing the results of dimensional stability and water absorption of composite aerogels, it can be claimed that, nanocomposite aerogel containing 50% cellulose with equal proportions of chitosan/protein nanofibrils can be regarded as the optimum sample for further studies. Notably, all three-component aerogels containing PNF exhibited a maximum absorption capacity of 70 mg g-1 and the highest 100% removal efficiency for Congo red anionic dye.

One of the disadvantages of recycled fibers is the significant loss of mechanical strength of the paper due to the decrease in the bond between the fibers. So far, many types of research have reported the application of cellulose nanofibers in the production processes of paper products. The results of previous research show that the use of cellulose nanofibers strengthens paper products. However, the amount of this reinforcement is different according to the type of cellulose nanofibers used. Nano lignocellulosic fibers of paulownia fortune (Nano wood) consist of nanoscale fibers with the same chemical composition as wood, which is produced mechanically without the use of chemicals from lignocellulosic biomass at ambient temperature. This material is a brown gel, which has a completely environmentally friendly production process. The objective of this study was to investigate the effect of adding Paulownia nano-wood on the improvement of pulp from old corrugated containers (OCC).

The pulp was prepared from OCC collected and after refining and obtaining a flow rate of 380 ± 20 ml, different amounts of paulownias nano-wood (1, 2, and 3%) and cationic polyacrylamide (0.1, 0.2, and 0.3%) was added to it. Finally, standard hand sheet papers were made from these treatments, and their physical and mechanical properties were measured according to the TAPPI standards.

Using nano wood and cationic polyacrylamide simultaneously causes a significant increase in resistance properties. The results show that the simultaneous addition of cationic polyacrylamide-nano wood to the pulp obtained from old corrugated containers increases the resistance to air permeability and density due to the improvement of the content of the bond and also the reduction of the porosity of the paper structure. According to the results, the highest strength in the nano lignocellulosic fibers -cationic polyacrylamide system among different treatments was observed in samples containing 1 % of nano wood and 0.3 % of cationic polyacrylamide. The results of evaluating the physical properties of the papers showed that the density and air resistance of paper (Gurley method) increases with the addition of lignocellulosic nanofibers - cationic polyacrylamide in the paper. The results show that the simultaneous addition of lignocellulosic nanofibers - cationic polyacrylamide to the pulp obtained from Old corrugated container (OCC) increases the air resistance of paper and density due to the improvement of bonds and also the reduction of the porosity of the paper structure.

Due to its positive charge, cationic polyacrylamide improves the bonding between fibers and restores lost bonds, and also prevents the wastage of fine nano wood particles and thus improves the properties of the paper. The statistical analysis showed that 95 % confidence in accuracy between treatments in the mechanical strengths (burst, RCT, and tensile strengths) is different. Using optimum levels of nano lignocellulosic fibers improves these strengths. According to the results, the best’s amount of strength among different treatments in the lignocellulosic nanofibers-cationic polyacrylamide system is observed in samples containing 1% lignocellulosic nanofibers and 0.3% cationic polyacrylamide.