فصلنامه پژوهشهای علوم و فناوری چوب و جنگل
سال بیست و نهم شماره 3 (پاییز 1401)

Nanocelluloses have attracted the attention of some countries due to their potential for economic growth. There are two approaches to obtain nanocellulose: bottom-up strategy (bacterial nanocellulose) and top-down strategy (plant-based nanocellulose).

Nano cellulose with Challenges in part production and Consumption is had encounter. That with using of Delphi method criterions and sub criterions very important effective on production and Consumption those were become Identify And 10 questionnaire according Delphi method with gamut likert design that this questionnaire contain criterion and sub criterion be and which of options contain 6 criterion to give scoring very low, low, middle, high and very high, is having. and to aces among professors university expert and Production companies and Private technology and knowledge base in 3 step or (rank) presentation and to has completed. Until position production and Consumption Nano cellulose with using of Delphi technical check and analysis its be made.

According to the results, in the criterion (raw materials and product), 2 sub-criteria (development of approach - access to raw materials inside and outside the province) with an average of less than 3 were removed from the 11 important sub-criteria in the first round, and 9 sub-criteria remained in the second and third rounds. In the criterion (economic and sales marketing) 4 sub-criteria (customer satisfaction - sales system - export opportunities - transportation costs) with an average of less than 3 were removed from 13 important sub-criteria in the first round, and 9 sub-criteria remained in the second and third rounds. In the criterion (competitive and infrastructure), 2 sub-criteria (purchasing power of nanocellulose suppliers - discount power of nanocellulose suppliers) with an average of less than 3 were removed from 9 important sub-criteria in the first round, and 7 sub-criteria remained in the second and third rounds, and 3 sub-criteria (existence of educational, university, technical-professional centers - living and welfare facilities of human resources - human resource management) with an average of less than 3 in the criterion (technical-human) were removed from 10 important sub-criteria in the first round, and 7 sub-criteria remained in second and third rounds. The reliability Cronbach's Alpha of the first round is 0.825, the second round is 0.815 and the third round is 0.845.

Indicators effective on production and Consumption Nano cellulose in 3 step questionnaire be full by aces trend dissection and analysis contain be meaning and too in research coordination coefficient kendal in rank second and third 0.57 is having. that a sign of been effective this factories on production and Consumption Nano cellulose in iran is having that in process production and marketing and supply the products Nano cellulose this factories important and effective must at looking.

Magnetic wood is one of the wood nanotechnology products with a wide range of potential industrial applications. Superparamagnetic wood is generally produced by in situ synthesis of magnetic nanoparticles in the wood structure. Among the various species of wood used for the production of magnetic wood, the fast-growing species are becoming increasingly important. On the other hand, the inherent properties of wood, such as its water absorption, dimensional instability, and susceptibility to biodegradation and weathering, may limit the potential of magnetic wood as an advanced engineering material. This study aimed to evaluate the effect of furfurylation on modifying the physical and mechanical properties of superparamagnetic poplar wood prepared by in situ synthesis of magnetic nanoparticles.

In situ synthesis of magnetite nanoparticles in poplar wood (Populus deltoides) was performed using iron II and III chloride solutions in a 2:1 molar ratio in a vacuum/pressure chamber. Then the treated wood was converted into magnetic wood by draining the solution of iron cations and replacing it with a one-molar solution of sodium hydroxide. After washing the excess alkali solution and drying, the magnetic poplar wood was treated with two different concentrations of a furfuryl alcohol solution under the vacuum/pressure system and converted into wood polymer after performing the necessary heat treatments. The specimens were characterized using a field emission scanning electron microscope, X-ray diffraction, vibrating sample magnetometry, a static bending test, and long-term water absorption and thickness swelling tests.

The conversion of poplar wood to magnetic wood reduced the weight percent gain (WPG) resulting from the furfurylation process. The saturation magnetization of the magnetic wood decreased significantly after furfurylation and conversion to the wood-polymer. Changing the concentration of the furfuryl alcohol solution had no significant effect on the saturation magnetization of the prepared magnetic wood polymers. The furfurylation treatment significantly reduced the specimens' flexural strength and flexural modulus. The flexural properties of magnetic and non-magnetic wood polymer specimens treated with the same concentration of furfuryl alcohol solution showed no significant difference. Microscopic examination of the fracture surface of the cell wall of the wood in the specimens subjected to the bending test showed the effect of furfurylation in transforming the behavior of the cell wall of the fibers from ductile to brittle, which was consistent with the results of the bending test. On the other hand, as the WPG increased, the specimens' long-term water absorption and thickness swelling decreased. Magnetic wood-polymer specimens had higher water absorption values and thickness swelling than non-magnetic wood-polymer specimens.

Based on the results of this study, it is recommended that magnetic poplar wood, if it must be used in high-humidity environments, be converted to magnetic wood-polymer with furfuryl alcohol, provided it has the required mechanical properties.

The reduction of forest wood resources has increased the necessity of using alternative primary resources including weedy non-wood plants, wood of fast-growing trees and agricultural residues in papermaking industries. On the other hand, most of the country's agricultural waste is consumed in animal husbandry industries, and wood farming also faces many challenges due to costs such as removing the roots after cutting the tree. Hence the need to use a weedy non-wood raw material seems essential. terjin (Saccharum ravennae) is one of the native weedy non-wood resources of the country, which has a good distribution in the country, and so far, its potential for use has not been evaluated. Therefore, the purpose of this research is to investigate the chemical and morphological characteristics of terjin, as well as the production and evaluation of refined and unrefined soda-anthraquinone pulp from it as a raw material to offer to papermaking industries.

In this research, terjin leaves were obtained from Gorgan region located in Golestan province. In order to measure the biometric characteristics of terjin, the samples were cut using the Franklin method, and then the dimensions of its fibers were measured using an optical microscope, and then their biometric coefficients were calculated. In order to measure the chemical properties of the fibers, the samples were first grinded and then their chemical properties, including the percentage of ash, extractives, lignin (klason) and cellulose were also measured based on the TAPPI standard. In order to prepare pulp from terjin, the samples were cooked at different levels of time (30 and 60 minutes) and chemical (alkalinity 14, 16 and 18%) under a temperature of 160 °C and 0.1% anthraquinone consumption, and then their yield, freeness and kappa number was measured. In the following, the pulps were refined to freeness of 350 ± 20 ml CSF, and then handsheet paper with a grammage of 60 g/m2 was prepared from refined and unrefined pulps, and their physical, optical and resistance characteristics were measured by TAPPI standards. Finally, the results were evaluated and analyzed using one-way analysis of variance and Duncan's test in SPSS software environment.

The results showed that the length, diameter, lumen diameter and wall thickness of the fibers were 1.85 mm, 10.82 µm, 5.32 µm and 2.75 µm, respectively; and biometric coefficients including Slenderness ratio, Flexibility coefficient and Runkel ratio were 171.14, 49.12 and 103.60 respectively. Its chemical composition included percentage of ash, extractive, lignin and cellulose were 5.75, 2.53, 26.73 and 44.63 respectively. The results of pulping showed that with the increase of alkalinity percentage and cooking time, yield, kappa number and freeness of pulp decreased. Also, the results showed that refining and increasing the alkalinity percentage and cooking time increase the density, decrease the opacity and increase the resistance characteristics of pulp. According to the results, the brightness increased with the increase in alkalinity percentage, while the increase in cooking time and the use of refining treatment did not have a significant effect on the brightness of the soda-anthraquinone pulp obtained from terjin. According to the results, the best characteristics were obtained after refining the pulp obtained from cooking at 18% alkalinity for 30 and 60 minutes, and also at 16% alkalinity for 60 minutes.

In general, terjin has better morphological and chemical characteristics than many non-woody plants, and in some cases, such as fiber length, its characteristics are comparable to hardwood. Also, refined and unrefined soda-anthraquinone pulp of terjin has relatively good and acceptable papermaking characteristics, and it can be suggested to the papermaking industry as a part of the raw material for the production of pulp.

Forests are the main part of renewable resources and play an influential role in economic change and sustainable development. Therefore, sufficient knowledge of these resources is essential for the appropriate management of forests. A forestry plan must guarantee the production of goods and services without seriously damaging the values of the forest and the future of forest production. In this way, a management plan will be successful in the various aspects such as scientific, ecological, executive, economic, and social dimensions that can be achieved together. The balance between these aspects will be predicted and implemented, although it is hard to achieve this balance. The general purpose of this study was to identify the components affecting the performance of forestry projects in Iran and rank them from the perspective of experts to stop the implementation of forestry projects based on these criteria.

For this purpose, Fuzzy Delphi method based on the data from experts opinions at the three criteria level, 1- scientific criterion (included 7 component), 2- managerial-executive criterion (included 18 component) and 3- legal criterion (included 9 component) and Finally, based on the final weight, the highest to the lowest value of the importance of the factors were used, respectively. Fuzzy Delphi is a method in which the mental data of experts is transformed into almost objective data using statistical analysis. This method leads to a consensus in decision-making and reaching a stable point. In this method, experts were first asked to enter their predictions in the form of triangular fuzzy numbers in the form of a minimum and maximum importance in the questionnaire. Then a group of fuzzy numbers is formed and calculated by the aggregation of ideas.

The results of scientific component showed that the coordination and communication between the scientific, executive and legal factors with a final weight of 0.181 had the highest degree of importance. The component of the high dependence of forest dwellers' livelihoods on the utilization of natural resources with a final weight of 0.866 was the first priority among management-executive component. The specificity of the project supervisor and the observer's activity and attention to the reports, as well as the forest destruction and wood smuggling with a final weight of 0.150 had the highest final weight as the legal component.

Although there is no single method for evaluating and determining the criteria and indicators for the effectiveness of forest management, research on identifying priorities, especially for forestry projects in different parts of the country, has significantly helped to evaluate, improve performance, deciding on the future period of implementation or stop or change procedures to protect activities.

Ecotourism is a concept which has attracted global attention in recent years and is usually associated with the concepts of natural resource conservation and rural development. Studies show that ecotourism has the capacity to improve the livelihood of the local people in a participatory management method. Therefore, a tool should be used to analyze the cooperative behavior of the host community as an environmental behavior in the natural ecosystems conservation. The purpose of this study is to investigate the conservation behavior of the host community of forest based ecotourism in forest conservation using the value-belief-norm model.

A questionnaire was used to collect research data. The questionnaire was prepared based on the value-belief-norm model and in consultation with a group of experts including forestry, rural extension, ecotourism and natural resources experts. After confirming the integrity and reliability of questionnaire, the data were collected via the face-to-face interviews. 278 completed questionnaires were used in the analysis process. Data analysis was conducted for descriptive statistics using SPSS23 software and for inferential statistics (to examine the correlation between independent and dependent variables in the form of structural equation modeling) using Smart Pls software.

Comparing the obtained values of the fit indices in Stern's value-belief-norm model with the desired values shows that these values are within the standard range. Therefore, based on the values of the presented indicators, it can be concluded that the model used to investigate the intention of the host villagers to participate in forest conservation has a good fit. Also, the findings of the research indicated that all research hypotheses were confirmed in the value-belief-norm model. The results showed that the research variables in this model are able to explain 71/8% of the host community's intention for forest conservation behaviors.

The results of the research showed that biosphere values, altruistic values, sense of responsibility and awareness of the consequences have an effect on the cooperative behavior of the host community for forest protection. Considering the relationship and interaction of people with natural resources and strong religious beliefs and teachings about the value of natural resources and respect for them among people, this issue can be used to strengthen the pro environmental behavior of forest protection and carry out protective behavior. The study highlighted a strong moral belief among the tourism host community. This issue can be used as a ecotourism based conservation tool for zagros forests.

Identification and mapping of tree species at single-tree levels using remotely sensed data is important in sustainable forest management. On the other hand, UAVs provide possibilities to acquire remotely sensed data with high spatial and temporal resolution that facilitate monitoring single tree and assessing quantitative and qualitative characteristics of trees such as species types. Methods based on machine learning can identify species types on UAV colour images but not with high accuracies. Additionally, similarity of trees in visible wavelengths registered on UAV colour images causes errors in species recognition. Therefore, this study was aimed to evaluate combination of UAV-based colour imagery and digital surface model (DSM) and deep learning algorithms in species recognition of a Pistacia-Amygdalus stand.

A part of Pistacia-Amygdalus stands in the wild pistachio research forest with an area of 24 ha was selected for this study. The study area was covered by 649 colour images with spatial resolution of 3.5 cm in 16 flight lines acquired by a Phantom 4Pro UAV. In addition to orthophoto, the DSM with similar spatial resolution was obtained by inverse distance weighted (IDW) method. The colour images and the combination of colour images and DSM were then used by Convolutional Neural Networks (CNNs) to identify Pistacia trees and Amygdalus shrubs. Results were evaluated by indices of accuracy assessment (e.g., accuracy, area under curve (AUC) of receiver operating characteristics).

The results on colour images showed that Amygdalus shrubs (accuracy=0.77, AUC=0.82) were identified with slightly higher accuracy than Pistacia trees (accuracy=0.76, AUC=0.80). Moreover, the results on combination of colour images and DSM showed that Pistacia trees (accuracy=0.85, AUC=0.85) were identified with higher accuracy than Amygdalus shrubs (accuracy=0.81, AUC=0.83). The final map was consisted of 455 Pistacia trees and 1951 Amygdalus shrubs. In addition, the visual interpretation of results revealed that species recognition on the combination of colour images and DSM had higher accuracy despite almost similar values of the indices of accuracy assessment.

In general, the present study explored that combination of colour images and DSM can facilitate species recognition of Pistacia trees and Amygdalus shrubs. Furthermore, this study confirms the capability of CNN in mapping of species at the individual level.

The consequences of global climate change that Iran and other countries are now facing are the pressures and stresses that have been placed on terrestrial ecosystems, especially forests. This is a serious threat to the extinction of many species. Evaluation of plant functional traits changes along height from sea level gradient is very useful in order to understand the adaptation of communities and their response to the environment in climate change. The purpose of this study was to understand the trend of changes in leaf morphological traits and also to investigate the segregation of populations of three important broadleaf species of Hyrcanian forests in the altitude gradient.

For this purpose, five populations at altitudes of 300, 600, 1200, 900 and 1500 m above sea level in the forests of Neka region were selected according to the natural distribution of the studied species. Leaf sampling was performed in four directions and in the middle of tree canopies and seven leaf morphological traits were measured and calculated. Data were processed using analysis of variance, Duncan multiple comparisons and diagnostic analysis.

The results of analysis of variance showed that all leaf traits of all three species have significant differences between different classes of altitude. The trend of changes in the traits of the three species in the altitude gradient was different. Diagnostic analysis of traits in altitude classes performed grouping of the individuals with high accuracy for all three species. The results of this study showed that among the leaf morphological traits of all three species of oak, hornbeam and beech in response to altitude, the traits of leaf area, perimeter, length and width are considered as the best traits.

In general, considering the trend of changes in leaf morphological traits of species in the altitude gradient based on the nature of the species in the study area and good detection of phenotypic differences of populations by Diagnostic analysis concludes that the forces of natural selection in order to adapt and develop the populations of these three species in the altitude gradient of this region, have a good effect on leaf characteristics and have caused the separation of populations. Also, the leaf area trait was introduced as the most effective applied trait and the difference in height of 300 meters was proposed as hypothetical boundaries of the separation of altitude provenance of all three species. Therefore, with the help of the findings of this study, the stability of separate populations of all three species against some consequences of climate change can be evaluated and also in choosing the optimal forest management method to protect the genetic resources of species and improving risk prevention management can be used.

The climatic conditions governing the Hyrcanian forests and also the decrease in the income of forestry projects due to the cessation of forest exploitation caused the protection and maintenance of forest roads to be almost stopped and as a result, the deterioration of the roads especially in steep slopes. In this situation, the dense surface of the forest roads during heavy rains causes the production of runoff and the washing of loose and fine-grained materials, which leads to the formation of sediment.

In this research, the effects of three treatments including type of open-top culverts, installing distance of open top culverts and amount of rainfall on road materials loss from steep sections (6-9%) were investigated and then the economic efficiency was evaluated. Open top culverts including grooved and ridged culverts and rubber culverts with three repetitions up to the depth of the road bed and at an angle of 40 degrees to the road axis and at distances of 30 and 60 meters from the top of the dome arches (where the runoff originates), parts of the network The roads of Dr. Bahramnia's forestry plan were installed and implemented. Several road segments with a length of 60 meter and without installation of open-top culvert were determined as control plots. The amount of sediment coming out of the drains after 3 rainfall events (27, 33 and 70 mm) was measured in the sampling traps. Then the amount of material wastage was calculated.

The results showed that the type of open-top embankments, the installation distance and also the mutual effects between them did not have a significant effect on the amount of soil loss or surface materials of forest roads. The highest amount of top material loss was related to the control treatment and also the third rain event. The increase in the distance between the installation of the beams did not have any significant effect on the amount of material wastage, but in general, the amount of material wastage slightly increased with the increase of the installation distance of the beams. The average loss of materials at the installation distances of 30 meters and 60 meters was 183.5 and 184.9 grams per square meter for the furrow and ridge treatment, respectively, and 171.8 and 188.3 grams per square meter for the rubber treatment, respectively. The evaluation of the costs of construction, installation and implementation of the treatments showed that the groove and stack has a more favorable economic function than the rubber one.

Considering the similar performance of the two open culverts and also the cost-effectiveness of the groove and pile culverts, it is necessary to introduce this type of culvert to the executive bodies for the management of runoff and sediment in road segment of 6-9% in study area. Also, at both distances of 30 and 60 meters, the surface flow was directed outside the crossing width at the right time before it caused the washing and channelization of the road surface. Therefore, it is possible to increase the installation distance of the culverts to assess the runoff and sediment behavior.