فصلنامه پژوهشهای علوم و فناوری چوب و جنگل
سال بیست و چهارم شماره 3 (پاییز 1396)

The Zagros forests, mostly located in semi-arid regions, are not safe from fire hazards, and fire affects these coppice forests continuously. Studying the change in the composition and quantity of vegetation in the areas exposed to fire can determine the extent of damage, and the potential of the region for reclamation. The aim of this study was to investigate the composition, diversity, and response of understory herbaceous plants to fire in the Persian oak forests in the Tulgahi region of Kohgilouyeh and Boyer-Ahmad province.
The fire took place in the summer of 2010. Four years after the fire, the characteristics of herbaceous vegetation, including composition and biodiversity of plants, were measured. Sampling of herbaceous plants was carried out within each main plot of 1000 square meters (designed to measure the forest parameters with systematic random sampling in a 50 by 100 meter grid), five subplots of one square meter were sampled in the center and four angles of main plots and the species type and cover percentage were recorded. In total, 200 subplots were measured in the fire and control regions (100 subplots at each region). The diversity indices were calculated in the PAST software, and plant species response to fire was determined with redundancy analysis (RDA) using Canoco 4.5.
The results showed that out of 72 herbaceous species identified, 22 species were exclusively found in the fire region, 9 species exclusively in the control region, and 41 species were shared between the two regions. The results of mean comparisons showed that among the study species, 17 species had a significant response to the fire in terms of canopy cover percentage. The fire caused the canopy cover percentage of Rubiaceae and Gramineae to increase significantly compared to control. The results of biodiversity indices revealed that no significant difference was found between the two regions in terms of biodiversity indices. The redundancy analysis (RDA) results showed that herbaceous species had different responses to fire, so that canopy cover species of Onobrychis sativa, Orobanche sp., Hordeum glaucum, Pimpinella sp., Bellevalia sp., Bromus donthoniae, Bromus tectorum and Chardinia orientalis were increased in the regions where fire occurred.
The results of this research showed that fire was an important and effective factor, causing to increase of grasses and annual forbs significantly after four years of its occurrence. In contrast, the presence of perennial grasses and forbs was decreased significantly by fire in the understory of Persian oak forests.

Considering decreasing trend in wood harvesting potential of Hyrcanian forests, we need to plan for utilization of other ecosystem services, such as ecotourism, more than past. For ecotourism planning, comprehensive information of ecological beauty and natural landscape structure should be summarized. On the other hand, accurate evaluation of different landscapes in a region requires comprehensive information of affective criteria, and its impact on user perception of landscape quality. Locating lookouts, which have high quality in landscape structure, is known as the first step to promote aesthetic quality of landscape and protection of natural ecosystems. This research aims to evaluate aesthetic quality of forest landscape using quantitative comprehensive approach and artificial neural network modeling for determination of the most effective landscape visual parameters in subjective aesthetic quality promotion of landscape.
The study area is three districts (with high diversity in landscape quality) of Khyrud research educational forest managed by Natural Resources College of University of Tehran which are named Patom, Namkhaneh and Gorazbon. In study forest, totally 200 landscapes, with different structure of tree cover and view composition, were selected to record landscapes characteristics. Landscape quality which is in the eyes of beholder, was evaluated in 200 studied landscapes.
In this study, in order to model the aesthetic quality evaluation of forest landscape, structural features and landscape parameters were recorded and aesthetic quality of landscape was classified in three classes of weak(1), desirable(2) and extremely desirable(3). Multilayer Perceptron network was used to data processing with artificial neural network.
Considering network coefficients of determination (Test samples) which is 0.88, 0.896, 0.969 in 1 to 3 classes, the accuracy of artificial neural network in aesthetic quality evaluation of landscape is assessed in extremely desirable level. Sensitivity analysis prioritizes landscape composition, tree diversity and thick trees view respectively to achieve class 1 and 2 in quality of forest landscape. On the other hand, tree diversity, landscape composition and view point respectively play a significant role in class 3 in quality of forest landscape.
results of the most effective variables on aesthetic quality of forest landscape, proved that landscape composition with higher diversity in its scenes, diversity in tree views with higher tree species and also thick and old trees in landscape should be a priority for forest landscape planning and management to achieve lookouts with higher quality of landscape in the eyes of beholders. This research prepared a new method for aesthetic quality evaluation of forest landscape and the introduced model is known as an environmental decision support system in forest ecosystems with an application in similar forests. Also practical criteria in aesthetic quality evaluation of forest landscape were introduced.

History of forest management planning in Zagros indicates that forest management goals have not been achieved. Lack of social acceptance of these plans by local communities is considered as the main reason of this problem. Public participation can help to solve this problem. This paper aims to determine barriers of public participation in Nameshir district of Baneh in Zagros forests. For this goal, 186 of local people were surveyed by a questionnaire method. Analyses of data showed majority of households are dependent on forestry products. Analysis of Local people opinions indicated that lack of local people involvement in forest management, ignoring of traditional knowledge in planning, high dependence of people on forest and willing to manage forest are more affecting factors that limit participation of people in forest management. Statistical analysis revealed a positive significant correlation between willing to participation and some factors including confidence level (p

Skid trails are considered as a completion of wood transport network and are closely related to the condition of road network, silviculture practices, logging methods, topography, slope, soil mechanical capabilities and other factors. The purpose of this study was to design skid trails in parcels No. 22 and 23 in Darabkola forest using GIS with AHP in order to cross paths on sustainable areas and a convenient access to the forest area. For this purpose, maps of slope, inventory per hectare, stream density, inaccessible areas (outcrop and regeneration), pedology, aspect, geology, forest type, and altitude, which are important factors in designing of skid road network, were used as layers of information and Evaluation of designed skid trails. The results of AHP showed that slope with a relative weight of 0.301 and altitude a relative weight of 0.029 had the most and least effects on designing of skid road network; the acceptable incompatibility was 0.08 in this case. Finally, two variants were designed for the study area. The first variant had a length of 2957.51 m and a density of 25.06 m/ha; the second variant had a length of 3853.85 m and a density of 32.66 m/ha. The situation of variants passes through different areas showed that 83.54% and 84.81% of the length of the skid trail was passed from very proper and proper areas in the first and second variants, respectively; 16.46% and 15.27% was passed from poor and very poor areas in the first and second variants, respectively. Compare designed variants using the nearest route showed that the average distance of each node to the track for the first variant was 64.77 meter and for the second variant was 45.56 meter. The results of this study showed that by considering the skidding distance of 140 m and with a maximum longitudinal slope of skid trail (% upward and -35% downward) the second variant was preferred due to the more passing percentage (84.81) on proper and very proper areas and lesser passing percentage (15.2) on poor and very poor areas and a cover percentage of 48.47% than the first variant with a passing percentage of 83.54% on proper and very proper areas and 16.46% on poor and very poor areas and a cover percentage of 32.18%. The evaluation results of the nearest path showed that the second variant had the best distribution because the average distance between each node to its path was lower.

Wych elm is one of the most invaluable native species in Hyrcanian forest. But due to Dutch elm disease outbreak in several decades ago, and illegal cutting of this species, its dominance in these forests has been significantly decreased. Hence, it must be adequately preserved from extinction. Therefore, maintaining and restoring this invaluable species is essential. Habitat suitability models could constitute a good tool for decision-making within the framework of applied forest ecology. They have mainly been used in strategies for conservation, planning and forest management. Habitat suitability or species distribution models are defined as statistical analysis algorithms that relate species’ field observations species data to environmental predictor variables. The aime of study is predicts the distribution of Wych elm species in Kheyroud forest using GLM and GAM models and Provide habitat suitability map with the best models.. Using digital elevation models and extracted primary and secondary topographic attributes from DEM, the habitat suitability of Wych elm was prepared in Kheyroud forests, Nowshar by using two common modeling techniques i.e. GLM and GAM. Due to the extent of the study area and being dispersed in the area, the locations of Wych elm individual trees with DBH > 10 cm were recorded by Global Positioning System by selective sampling. The primary and secondary topographic attributes calculated from digital elevation model with 12.5 m resolution along with soil characteristics, soil fertility and geology maps were then derived at each Wych elm location. Results showed that GAM outperforms GLM based on AUC, Kappa and TSS criteria. The results also indicated altitude and valley depth were the most important variables in determining the habitat suitability of Wych elm species. The results also showed that 62% of study area has acceptable potential for presence of Wych elm species. The results of this study showed that due to the optimal moisture, thermal, light and topographic conditions in mid-lands and also the high potential of this region for the presence of the Wych elm species, this area is the best habitat for this species. The results and methods used in this research can be used to assist the management decisions to conserve and restore the Wych elm and other rare and endangered species.

Bacground and Since the Long-term forest ecosystems sustainability is related to soil quality, forest soils study and evaluation of soil physico-chemical properties is necessary for soil forming process. This study was designed to compare the environmental characteristics and ordination of woody plant species and their relation in Ilam forest. For this purpose in Cercis griffithii, Cerasus microcarpa, Amygdalus Arabica, Amygdalus elaeagnifolia, Daphne mucronata Royle, Crataegus puntica, Lonicera nummularifolia and Acer cinerascen stands 4 Sampling location were randomly selected. In each location, three soil samples were taken from the depth of 0-30 cm and pooled. Samples were transferred to laboratory and Soil physico-chemical properties including: pH, EC, P, N, K, Cao3, C, bulk density, saturation humidity and soil texture were determined.
Resuits: Our result indicted that the highest and least values of nitrogen and organic carbon were observed in Lonicera nummularifolia and Amygdalus arabica respectively. The highest phosphorus, potassium, saturation moisture, electrical conductivity and pH were observed in Acer cinerascens stand. Cercis griffithii had the highest bulk density value. The least and highest cao3 were belonged to the Lonicera nummularifolia and Cercis griffithii respectively. Furthermore, the most and least amount of sand were observed in Amygdalus Arabica and Amygdalus elaeagnifolia stands. The highest and least value of clay belonged to the Cerasus microcarpa and Lonicera nummularifolia stands respectively. Lonicera nummularifolia had the most and Amygdalus arabica olivler had the least amount of silt. Also, Amygdalus elaeagnifolia was in the higher elevation above sea level rather than other species. Acer cineracens and Lonicera nummularifolia were located in steeper slopes. The result of CCA (Conical Correspondence analysis) revealed that there are significant correlation between environmental factors and studied woody plants species. Soil organic Carbon, total nitrogen, phosphorus, potassium, calcium carbonate, electrical conductivity, clay, silt, sand, elevation and aspects have great impact on the presence or absence of studied woody plants species. Presence of Lonicera nummularifolia and Amygdalus elaeagnifolia together in a habitat with a similar conditions indicated the similarity of these two species for the site demands. Furthermore, higher phosphorus, potassium, total nitrogen, organic carbon, soil moisture and silt were observed in higher elevation. Also, the similarity of Daphne species, Crataegus puntica, Cerasus microcarpa and Cercis griffithii habitat might be interpreted by higher values of calcium carbonate and sand in these habitats. soil physico-chemical properties and environmental factors were significantly different in studied stands and these factors effects on presence or absence of species.

At recent decades, Non-wood forest products (NWFPs) have been considered as one of the important components in sustainable forest management and poverty reduction of local communities. These products are a sustainable income source for local people beside of other income source such as agriculture and animal husbandry. This factor create engagement and incentive to protect forests as sources of sustainable. Understanding the importance of these products without knowing the species and characteristics of quantity and quality of production of these species will be impossible. The aim of this study was to estimate the amount of production, the economic importance of these products in household’s income in three forest villages at Rudsar county of Guilan province. In this study, two methods were used. At first, inventory was used for estimating of fruit production and at second the socio-economic survey was done using questionnaire. Inventory was done systematically randomly with 30 samples with dimensions of 100 by 100 meters (one hectare). Within each sample, the nearest tree to the plot center was selected to measure the amount of production fruit. At the socio economic surveying 120 households at three villages was censed by the semi-structured interviews and direct observations in summer 2015. The results showed that the fruit production of each tree was about 25 kg. Based on the number of Diospyros lotus species per hectare (17 trees), about 425 kg fruit per hectare was produced. Total fruit collected by households of three villages of Lusara, Nurmash, and Siyahgal Chal was 3880 kg. The average annual harvest of households was 32 kg. Gross annual household income from fruit harvested varied from 230 to 2100 thousand Rials. The expected value of forest from fruit sources was 6050000 Rials per hectare. The fruit collection create employment for 15 person’s day annually. These products create a good income for households. But at the current situation, the share of income of these products was relatively low. In addition to income, it is led to creating the employment opportunities. According to high addition value of processing operations, processing has been stated as a main income source. Establishing the local cooperative, holding educational courses, setting up the processing factories can increase income of households from these products.

Aim and Beech is one of the most valuable industrial species in the Iran's Hyrcanian forests that has varieties of crown compositions with different species and soil fertility. Several studies have examined the role of canopy composition on biogeochemical cycles, and different results have been addressed. Different combinations of canopy covres create heterogeneity in different scales. Regarding to quantity and quality of input and output for flow of water and nutrients, the biogeochemical cycles will be so different. The aim of this study is to determine the revenue of pure and mixed crown of Hyrcanian beech in changes of biogeochemical cycles. In the above stratum of Experimental Forest Station of TMU, four crown compositions of beech spcies (i.e. beech-hornbeam, beech-maple, mixed beech including beech-hornbeam-maple and pure beech) were considered. Five replicates were selected for each composition and a total of twenty sample plots were set up in the forest. In the growth season (summer), litter and soil samples (50×50×10 cm) were collected from the neasrest location to main stem of beech trees. The samples were taken from four sides of trees and a composite sample was transferred to the laboratory. Litter’s (C and N) and soil (bulk density, texture, water content, pH, organic C, total N, microbial biomass C, microbial biomass N, earthworm density/biomass, emission of carbon dioxide, methane and nitrous oxide) features were measured.
Findings: Litter quality differed among the crown compositions, with the highest total N concentration and lowest organic C under mixed crown cover. Soil bulk density and water contents were respectively lower and higher under pure beech when compared with the other crown compositions. Soil texture was not significantly different among studied treatements, whereas greater amounts of pH and total N were detected under mixed crown covers. Soil organic C and C/N ratio were found to be significantly higher under pure beech than in the others. Pure beech showed the highest values of microbial biomass C (707.80 mg kg-1), microbial biomass N (50.79 mg kg-1), emission of carbon dioxide (0.54 mg CO2 m-2 d-1), nitrous oxide (0.38 mg N2O m-2 d-1) and the mixed composition showed the greater amounts of earthworm density (2.60 n m-2) and biomass (11.29 mg m-2). Methane emissions did not differ for the studied sites. Our findings showed that pure beech has more effects on C and N cycles in compred to the other crown compositions. Among different litter and soil characters, the water contens and organic C had more highlights roles in changes of these cycles.

In the Zagros forests, borer beetles will outbreaks after recent year's drought stress and physiological weakness in host tress and they causes accelerate mortality trend. In other hands charcoal disease outbreaks and then continue on oak decline has become one of the main problems of Iran oak forests. The aims of this research is studying the relationship between borer beetle damage and charcoal oak disease in the Kakasharaf forests of Khorram Aabad. The study area is the Kakasharaf forest of Khoram Abad is located on the Zogros forests in the west of Iran. This forest region is one of the infection focuses of charcoal disease. Inventory grid with dimensions 200 m × 150 m in the GIS software was drawn and placed randomly on the study area. To study the infected trees in the intersection grid sides, circular plots being 15-are (1500 sq m) in area were used. All the trees that were the hosts to Biscogniauxia mediterranea and borer beetles were considered. Used the linear regression for study of the relationship between charcoal disease and borer beetles damage and anowa test was used to investigate extent and damage intensity of charcoal disease and borer beetles in the sprouts of infected trees. The results showed that trees in the study area with the severity of 92.96 % and 47.04 % respectively to charcoal disease and borer beetles had been infected. Linear regression showed a strong relationship between the borer beetles damage with percentage of dieback (R2= 94.5), and the borer beetles damage with charcoal disease percent (R2= 85.9). The number of sprout showed significant differences at a confidence level of 99% for infected trees to charcoal disease and borer beetles. Cutting and pruning branches and twigs showed a significant impact on infected trees to borer beetles and charcoal disease, cuted trees more by borer beetles (41.43 %) and pruned trees more by charcoal disease were infected. In the study area human interferences such understory planting, fire, overgrazing livestocks, deforestation by man, cutting and pruning branches to make fuel and livestock feed and as well as ocurence environmental stresses are causses trees weakness and infected to pests and diseases. According to the results about two-thirds of trees to had cut and prune branches were infected to borer beetles and charcoal disease. Borer beetles can be important factor to charcoal disease transport between trees. So that this research showed there is strong relationship between damage borer beetles and charcoal disease.

Wood industry creates the direct and indirect jobs, and has an added value, also requirements of Iran can be eliminated and then the trade balance is positive. The wood industry performed added value to other materials such as plastic, glasses and building materials, and also, wood products have revenues to Rial and foreign currency even without reliance on forest resources. The import, production and employment, exports and trade balance reflects the status of wood industry. The methodology of the research was analytical and descriptive, and the number of employments and productions values and also, tariffs and trade of various wood products were investigated by using the published data. Basic information is gained through library research, databases and interviews with entrepreneurs based on cluster sampling, and then quantity values of products, employment and trade calculated for each manufacturing section, province and Iran. The results of the research is showe that employments quantity of wood industry is 100513 man in 4204 firm, and furniture section has a 59026 man in 2197 firm that more than half of total employment in this industry, and the employments quantity of other sections are 41487 man in 2007 firm. In there, sections of composites doors and veneered panels have 16385 man in 685 firm and 6358 man in 250 firm, respectively. Provinces of Gilan, Tehran, Mazandaran, West Azarbaijan and Khorasan Razavi have the most employment and firm in this industry. The most of employment rate is performed at province of Gilan with 18030 man in 835 firm. Often, furniture sections of wood industry have a negative trade balance. But, some of furniture subsections are related to local technology such as inlay and woodcarving have a revenues and positive trade balance. The section of furniture with 27 man in each firm is relatively small. Production of wooden flooring has a employment rate in wood industry, only but 0.7 percent of the internal demand is produced in within country and other demend values imported. The government performed the proper import duty, a ban on exports of raw materials, the products exports with persuasive duties. In this way, wood industry has supported to creation of added value and employment, but the trade balance is negative in the most parts of the wood industry. The endemic productions and adding countries with Preferential Tariff will develop the efficient markets for Iran. The government performed the proper import duty, a ban on exports of raw materials, the products exports with persuasive duties. In this way, wood industry has supported to creation of added value and employment, but the trade balance is negative in the most parts of the wood industry. The endemic productions and adding countries with Preferential Tariff will develop the efficient markets for Iran.

The capability of soft and fibrous tissues of plants to absorb noise; has been paid attention to be replaced with synthetic insolation boards. The use of lignocellulose materials has been widely considered because of some important factors like porous structure, high quantity availability, renewability as well as friendly environmental impacts (in contrast with fiber glasses). The lack of raw materials needed for industry also has diverted the attention to other new lignocellulose sources in Iran. So, in the present paper, the possibility of use of date palm (Phoenix dactylifera) as a leftover abundant source in south of Iran was studied in order to control and reduce acoustic pollutions. Two date palm trees with approximate diameters of 40 cm were freshly cut. Then, a disk with the average diameter of 12 cm was taken from every tree. The cubic experimental samples with dimensions of 12×12×2 were prepared from every disk and kept in plastic covers at freezing temperature. Before testing, cross section of samples were covered with epoxy adhesive and dried smoothly using a program. Finally the circular disks were prepared with two different diameters of 3 and 10 cm. To reach equilibrium moisture content, all samples were kept in a temperature-controlled room at 21°C and 65% relative humidity. Then disks were faced with two kinds of paperboards made with original date palm fibers (cortex and leaves fibers). Paperboards were provided in different basic weight of 130, 300 and 500 gr/cm2. Noise reduction coefficients (NRC) measurements were conducted on experimental samples in frequency range of 125 to 8000 (Hz) using impedance tube at the acoustic lab. The results showed that the insulation boards made from date palm had a high potential to absorb sound waves. In addition, their ability to dissipate acoustical waves were more pronounced when faced with a single layer of paperboard. A critical point was observed for NRC values at frequency of 2000 Hz. To compensate the given loss, applying a light paperboard (130 gr/cm2) of cortex fiber as well a heavy cover of leaves fiber (500 gr/cm2) could significantly increase NRC values. The high damping capacity of date palm samples was due to its particular anatomical structure. The vascular bundles embedded in parenchyma tissue provided a soft and porous surface to trap sound waves. An additional improvement on NRC values were obtained while facing disk samples with a layer of paperboard from low to high frequency range.

Background and scope Biometrical, physical and chemical properties of various wood species are important factors for determination, identification and their applications. Persian oak (Quercus brantii Lindl.) from Fagacea family is the most abundant and important tree species in west and southwest provinces of Iran that its biometrical, physical and chemical features is not studied so far. In this study, the mentioned properties of Persian oak from Lordegan township of Charmahal va Bakhtiari province were measured. The properties are included the biometrical (fiber length, fiber diameter, lumen and cell wall thickness), physical (density and volumetric shrinkage and swelling) and chemical properties (cellulose, hemicellulose, lignin and ash content). By measuring and investigating of these characterizes could be obtained valuable information in terms of cell elements and their relationships with natural durability.
Material and Methods This study was carried out in the forest of Atashgahe village in 55 kilometers from southwest of Lordegan Township. Lordegan Township is one the most important forest stands in Charmahal va Backtiari.
In this study, three normal trees with the diameter about 35cm were chosen to determine the biometrical (fiber length, fiber diameter, lumen and cell wall thickness), physical (density and volumetric shrinkage and swelling) and chemical features (cellulose, hemicelluloses, lignin and ash content). Form each tree; three disks were prepared at breast height of tree and testing samples were prepared along radial direction (pith, middle and bark) and then the mentioned properties were measured. Defiberation was done according to Franklin method. Determination of density was carried out based on ISO-3131standard. Cellulose, lignin and ash content were measured in accordance with TAPPI T-264-om-88 and T-222-6m-88 respectively. The content of ash was evaluated based on ASTM D1107-84.
Results The results indicated that fiber length, fiber diameter, lumen and cell wall thickness in radial direction were 967.67, 17.14, 3.67 and 6.41 micron, respectively. Results also showed that dry and basic density were 1.01±.10and 0.91 g/cm3, respectively. Volumetric shrinkage and swelling were 10.12 and 11.29 percent, respectively. The chemical results showed that content of cellulose, hemi cellulose, lignin and ash in sap- and heartwood were 37, 25, 1,19, 3,13, 41, 23, 2,6, 3,56 %, respectively.
Conclusion In general, the results of the present study showed that the biometrical and physical properties increased along radial direction from the pith to the bark. On the other hand, Persian oak with fiber length 0.97 mm is considered as moderate fibers. Chemical analysis indicated that cellulose, extractive and ash content in the heartwood were higher than the sapwood. There was no statistical significant different at 5 percent level between the cellulose content values in heartwood and sapwood. According to the measured dry density (1.03 g/cm3), Persian oak is categorized as heavy wood species.

Background and goals: This research changed into achieved with the intention of manufacturing dissolving pulp or alpha-cellulose from bagasse. Alpha-cellulose is generally used for making cellulose derivatives with advantage of being soluble in commonplace solvents in recognize to cellulose. Dissolving pulps have high alpha-cellulose and brightness, but very low hemicelluloses, ash, and extractives, with uniform molecular weight distribution.
Substances and Bagasse chips were pretreated beneath slight acidic situation the use of acetic acid at most temperature of a hundred 165 ºC, to obtain yield loss stages of approximately 20 and 30 percent in pre-extraction level. Bleachable pulps at kappa wide variety decrease than 12 had been created from each the pre-extracted samples, the usage of soda-AQ pulping technique at most cooking temperature of a hundred 165 ºC. The pulp samples produced under optimum situations, have been bleached by chlorine free bleaching (ECF) with AD0EpD1P bleaching sequence. The properties have been decided on the basis of policies TAPPI. In the end, a statistical evaluation of the effects of exams finished on dissolving pulps created from SPSS software program and t-test two samples become used. in this look at, dissolving pulp carries numerous alpha-cellulose from depithed Bagasse with acid pre-extraction and the soda-AQ pulping procedure turned into prepared. While that within the acid pre-extraction yield loss improved from 20 to 30, the alpha cellulose production increased but the degree of polymerization declined. In produce dissolving pulp, in addition lignin, hemicelluloses are also undesirable impurities, so the more material will be removed from the purity cellulose pulp increases, but with increasing destruction of the hemicellulose in the pre-extraction, may be cellulose chain additionally damaged, although alpha-cellulose to increase the degree of polymerization to be associated with high drop. Bagasse dissolving pulp having ninety two percentage alpha-cellulose with DP of 870, can also have restrained packages in making derivatives such as cellulose acetate and cellulose nitrates, however it is able to be used to supply decrease demand products such as viscose rayon and carboxymethyl cellulose. But, the yield and ash dissolving pulp were first-class. The outcomes of this studies evaluation with other research inside the discipline of dissolving pulp manufacturing and additionally considering that the bagasse produced in massive quantities inside the south of the united states, imparting a number of the pulp or alpha cellulose the used inside the manufacture of viscose rayon, as a minimum, can be planned based on bagasse as uncooked cloth.

Heavy metals such as Lead are toxic, stable and non-biological and causing numerous harmful effects on the environment and animals. Due to their mobility in natural water ecosystems and toxicity, the presence of heavy metals in surface water and ground water has become a major inorganic contamination problem. Discharge and treatment of industrial wastewater containing heavy metals are important issues in environmental protection. There are several methods to remove the heavy metals from aqueous solutions that adsorption is one of the best one. The aim of this study was to evaluate the efficiency of Bacterial Cellulose Nano Fibers Gel as adsorbent for the removal of Pb2 ions from aqueous solutions.
Material and Firstly, Bacterial Cellulose Nano Fibers Gel as a natural bio-nanomaterial was purchased with diameter in nanometer scale and length of a few microns. Secondly, the stock solution of Pb was prepared by dissolving Pb(NO3)2.6H2O in deionized water. The test solutions of various concentrations were prepared from the stock solution. The solution pH was adjusted using 0.1 M HNO3 and 0.1 M NaOH at the beginning of the experiment and not controlled afterwards. Batch experiments were conducted to study the effect of solution pH, temperature, contact time, absorbent amount and initial metal concentration and repeated on several occasions. Solution containing adsorbate and adsorbent was taken in 250 mL capacity conical flask and agitated at 120 rpm in a shaker at predetermined time intervals. Samples putted on the centrifuge with 4000 rpm for 5 minutes. Lead ions were determined spectrophotometrically by atomic absorption spectrophotometer. Finally, adsorption isotherm models and kinetic models were studied. Excel software were used for the analysis of data. The results of this study showed that the highest uptake was observed in condition of pH=5, contact time 50 minutes and temperature 25℃. Metal uptake capacity of adsorbent was very high so adsorption was done on favorable conditions. The batch isotherm studies showed that the adsorption data could be described by Freundlich model and kinetic model of the sorption were pseudo second order equation. Based on the results, it can be concluded that, Bacterial Cellulose Nano Fibers Gel could be successfully used as an adsorbent for the removal of heavy metals from aqueous solutions, especially for the industrial wastewaters. This bio-nanopolymer has high specific surface area and also is easy to use, renewable, and environmental friendly material. Comparing with other similar studies, this material was found to be an excellent adsorbent and can be successfully used by industries for removal of heavy metals.

Equilibrium moisture content of wood is a condition in which the world has at least an exchange of moisture with the environment. Wood moisture effects on most properties of wood. This feature is a function of relative humidity and temperature so that with increasing relative humidity, EMC increase and also with increasing of temperature EMC is decreased. There are many research regarding wood EMC in different places of the world and Iran. Also the annual trend of EMC was investigated. The objective of this study is trend analysis of EMC in a 25 year period of country. For this purpose, EMC was calculated from relative humidity and average annual temperature at 88 meteorological stations. Then by using the non-parametric Mann-Kendall method, the trend of temperature, relative humidity and EMC were analyzed. In this study the variation map of significant coefficients was drawn with the reverse of square distance by weight method regarding climate conditions. Finally the difference of first year amount with the last one and also the difference between first and last decade of the period were investigated in order to compare EMC. The results showed that in most studied stations the trend of temperature is increasing while the relative humidity and EMC in north beach, plane of Khouzestan and a major part of south-east have negative trend, significantly. The average of EMC in first and last decades changed from 0.35 % to 2.59 % and also between the first and last year of study period changed from 0.33 % in the first to 5.33 %. The main reason for this decline is related to the increasing temperature and decreasing of relative humidity. With respect to significant negative trend of EMC in North and Northern west forest of Iran and probable intense of this positive trend in the future, it seems that the wood quality and growth rate of forest trees in these regions will be changed. Furthermore, the decreasing trend of EMC, make environment drier for using the wooden furniture and products that need more attention to wood drying process and final EMC of products. Also the negative trend of EMC is an alarm for import wooden products and raw materials and export of wood products. With respect to significant negative trend of EMC in North and Northern west forest of Iran and probable intense of this positive trend in the future, it seems that the wood quality and growth rate of forest trees in these regions will be changed. Furthermore, the decreasing trend of EMC, make environment drier for using the wooden furniture and products that need more attention to wood drying process and final EMC of products. Also the negative trend of EMC is an alarm for import wooden products and raw materials and export of wood products.

In global scale, newspaper, printing and writing paper production from agriculture residues pulp such as bagasse fiber due to wood resource constraints and access to appropriate production process technology has been considered seriously. Nowadays, bagasse sugarcane could be the most important and the most suitable criteria into account as agricultural residues to Iran for use in new investments with appropriate and novel technology considered. The objective of this study was to investigate the comparative characteristics of pulp prepared from bagasse fiber by sulfur dioxide- ethanol- water (SEW) and soda process. Using by soda and SEW processes under different process conditions such as maximum cooking temperature (135 °C) and various pulping time (from 30 to 100 min), several cooking achieve a kappa number about 20 were performed. For soda pulp, purified water was used to remove black liquor and then pulps again by water pressure washed. In the SEW process, pulp collected after complete drainage of liquor on the 200 mesh, based on method using 40 v/v.% ethanol – water solution at 60 °C and then wash by water. After selecting the pulping process in terms of kappa number, pulps were refined up to 380 ml, CSF freeness. Finally the characteristics of pulp and paper prepared by SEW process evaluated according to TAPPI standard and with traditional processes (soda) in terms of physical, mechanical and optical characteristics were compared. Results showed that the density and caliper of the SEW paper is more than soda paper, bulk and air permeability is lower. SEW papers has poorer burst, tear and tensile strength than soda papers. The evaluation results of the optical properties showed that the SEW papers has higher brightness and low yellowness in comparison with soda papers. SEW papers has poorer opacity than soda papers Regarding to that the chemical delignification of SEW process is similar to that of acidic sulfite; It is expected to feature similar to the acidic sulfite pulp and paper. Therefore, due to low pulp fibers strength obtained from SEW process and requires far less refining the dough seems the process of the potential for a range of pulp and paper production such as special (dissolving pulp, paper greaseproof, Nano-cellulose) in other products with value-added. High brightness before bleaching is a clear advantage of the SEW solid residues which allows avoiding long bleaching sequences and reduce the use of chemical bleaching in order to sustainable development of pulp industry.