فصلنامه جنگل و فرآورده های چوب
سال هفتاد و سوم شماره 3 (پاییز 1399)

Hyrcanian forests play an important role in absorbing carbon dioxide and reducing the severity of climate change and global warming. The accurate estimation of actual evapotranspiration can help to plan for conservation and management of these forests and their water resources. Direct measurement methods for evapotranspiration have limitations, one of the most important of them is the pointed measurements. Methods for distance measuring have been developed to address these constraints. The purpose of this study was to prepare and estimate actual instantaneous () and daily () evapotranspiration maps from Landsat 8 satellite imagery and SEBAL model in Hyrcanian forests. For this purpose, Landsat 8 satellite images were prepared in two different dates, i.e. 2014/7/26 and 2016/5/28 in 200 thousand hectares of Hyrcanian forests in the cities of Pol-Sefid and Kiasar, and after processing and calculations, latent heat flux was estimated from images and from that basis,  and  maps were prepared. To evaluate these maps,  and land values were calculated using weather data of Pol-Sefid and Kiasar stations and the FAO Penman Monteith method. The estimated  and  means at the Pol-Sefid station were 0.53 and 5.39 and at Kiasar station, 0.48 and 4.98 respectively. The calculated mean of these two parameters, respectively, were 0.60 and 6.16, at the Pol-sefid station and 0.55 and 5.82, at the Kiasar station. The results showed that the percentage of estimated relative differences for  and is 0.068 and 0.809 respectively, and mean percentage of estimated relative differences for  and is 11.99% and 13.56%, respectively, which in total shows the high ability of the used approach for evapotranspiration maps.

The present study was carried out to investigate the effect of two mycorrhizal fungi and two growth-promoting rhizobacteria on survival and growth traits of Myrtus communis L. in water deficit conditions, as a completely randomized factorial design. Drought stress in three levels: 100% field capacity (without stress), 60% field capacity (mild stress) and 30% field capacity (severe stress) and biofertilizer in seven levels: control (without inoculation); inoculation with mycorrhizals of Funneliformis mosseae, Rhizophagus intraradices, and combination of these two fungi; inoculation with rhizobacterias of Pseudomonas fluorescens, P. putida, and combination of these two bacteria was considered in three replicates. Drought stress reduced and biofertilizers (in particular, composition of fungus, and combination of bacterias) increased the studied traits. In severe water deficit, combined treatments of fungal or bacterial improved height increment by 28-31%, leaf biomass by 51-52%, root biomass by 36-42%, total biomass by 37-41% and survival by 50% compared with the control (non-inoculation) ones. In severe drought stress, almost 50% of the seedlings survived without inoculation and 90-100% of them with inoculation, indicating the high tolerance of this species to drought. Due to the reduction of the destructive effect of water stress on M. communis seedling traits using biofertilizers, the use of these treatments, especially the combination of two fungi of Funneliformis mosseae and Rhizophagus intraradices or two rhizobacteria of Pseudomonas fluorescens and P. putida can be useful to improve seedling's growth characteristics.

It is important to be aware of the spatial dependence structure of different soil properties in natural resources to achieve more production and better management. This study aimed to determine the determining factors controlling spatial variations of macronutrient (NPK) by geostatistics. In the present study, 150 surface soil samples were collected from forests of northern Iran and some variables, including nitrogen, phosphorus and potassium were measured. The half-variance was selected to determine the spatial correlation and the best fitted models on half-variance for variables of nitrogen, phosphorus and potassium were spherical. Also, the effective range for these variables was obtained, which was equal to 530/80, 720/20 and 520/80 meters, respectively. Interpolation was performed using traditional Ordinary Kriging (OK), the inverse distance weighting (IDW) and radial basis function (RBF) techniques using ARC GIS and GS+ software and the accuracy of the distribution map of these variables was calculated using mean absolute error (MAE) and Root Mean Square Error (RMSE). According to the results, the OK technique for the variables of nitrogen, phosphorus and potassium variables was considered as the best interpolation method for estimating the variables in areas where sampling was not performed, because it had the highest accuracy and lowest error.

Ectomycorrhizal fungi can increase the quality and quantity of seedlings by increasing plant resistance to environmental stresses, and increasing growth and nutrient uptake in forest nurseries. In order to study the effect of ectomycorrhizal fungi on phosphate (P) uptake and growth of Alnus glutinosa seedlings, an experiment was conducted in a completely randomized design with four treatments including ectomycorrhizal fungi: Cenoccum geophilum, Lactarius sp, 150 kg/ha phosphate and control in three replications. A soil with low available P content were collected from Shalman Forest Seed and Seedling Research Station, and after sterilization by autoclave, was distributed in pots. In each pot, one seedling of Alnus glutinosa were planted and inoculated with the desired treatment. After ten weeks of inoculation, seedlings were harvested and their growth and nutritional characteristics were measured. The results showed that fungi inoculations significantly increased diameter, height and dry weight of seedlings by 30% compared with the control. In addition, ectomycorrhizal fungi increased nitrogen, phosphorus and potassium concentration in alder seedlings by 18, 82 and 61%, respectively. There was a significant difference between the percentages of alder root colonization between two fungi, but there was no significant difference in the efficiency of inoculation between the ectomycorrhizal fungi. It looks like that Lactarius is more effective compared with Cenococcum geophilum. Therefore, it can be concluded that ectomycorrhizal fungi improve growth and nutrition of alder seedlings, but further studies are needed to identify more efficient ectomycorrhizal fungi.

In nature, Leaf litter of different plant species is typically mixed and the mixtures decompose together. Leaf litter mixing effects may be caused by chemical interactions between the component leaf litters, by changes in the microenvironment in which the litter is decomposed or by changes in the diversity of associated microorganisms. The purpose of this study was to evaluate the interactions between black pine needles and tree of heaven litters using the litterbag method in Shahed's forest park of Malayer. For this purpose, 120 litterbags placed in the study area and incubated for 180 days at 30, 60, 120 and 180 days. In this study, mass loss was measured and non-additive effects of litter composition was studied regarding the nutrient dynamics and release. The results showed that tree of heaven litter had a higher quality than black pine needles (nitrogen values and C: N ratio of tree of heaven litter were 6.42 mg/g and 0.33 while the values for pine needles were 3.31 mg/g and 0.71, respectively). The non-additive effects of litter mixtures regarding the rate of decomposition and nutrient dynamics of black pine needles such as nitrogen, phosphorus and calcium were positive and neutral for potassium and magnesium. In addition, the non-additive effects of pine needles on the tree of heaven litter was negative in terms of nitrogen dynamics and were neutral regarding phosphorus, potassium, calcium and magnesium. According to the results of the study, no positive non-additive effects was observed on nutrient release. Overall, the results of this study confirmed the positive non-additive effects of tree of heaven litter on black pine needles in terms of the decomposition, dynamics of nitrogen, phosphorus and calcium concentrations of the needles.

In this study, flexural reinforcement of 3-layer screwed CLT made of poplar (Populous alba) and polyurethane glue was investigated. Static bending test was performed by Instron according to ASTM D4761. The variables of this study were types of reinforcing (aluminum sheet and glass fiber reinforcement polymer (GFRP) wrap) and arrangements of reinforcers (no.1: bonded on the bottom (tension) side; no.2: bonded on the bottom and top (tension and compression side); no.3: bonded on the bottom, top and between two bottom layers; no.4: bonded on the bottom, top and among layers). The results showed that the higher MOR and MOE were related to major direction of CLT reinforced with aluminum with configuration of no.1. The lower MOR and MOE were observed in minor direction of CLT reinforced with GFRP with configuration of no.1. The increasing percentage of the MOR and MOE in minor direction of CLT reinforced with aluminum were 195.1 and 344.6% and in major direction of them were 89.3 and 50.8%, respectively in comparison with control specimens. When CLT panel were reinforced with GFRP, the increasing percentage of MOR and MOE in the minor direction of CLT were 42.8 and 21.3% and in major direction of CLT were, respectively 46.1 and 12.7% in comparison with control specimens. The results showed that MOR and MOE of CLT reinforced with aluminum sheet were higher than those reinforced with GFRP wraps. Failure modes of CLT were changed by reinforcing from brittle to ductile and consequently increased their flexural strength.

The purpose of this study was to fabricate nano filters to adsorb particulate matters less than 2.5 μm using phthalimide modified cellulose nanofibers. Modification of cellulose nanoparticles with phthalimide was performed on acetic acid with the cellulose to phthalimide nanofiber ratios of 1:0, 1:0.5, 1:1 and 1:1.5 wt%. Modified cellulose nanofibers were evaluated by various techniques including SEM and ZP (zeta potential). Finally, cellulose nanofibers, both pure and unmodified, were evaluated for the adsorption of particulate matters and compared with the control filter (HEPA). SEM analysis showed no significant change in the size and structure of cellulose nanofibers due to modification, but with increasing phthalimide content, the specific surface area increased while porosity and pore diameter decreased. The results of the effect of temperature on the adsorption of particulate matters showed that the highest adsorption of particulate matters less than 0.1 μm was related to 1.5% phthalimide-modified cellulose nanofibers and 65°C (76%). However, the adsorption of particulate matter was above 0.3 μm for all purified and modified cellulose nanofibers.

In this research,the effect of alkali treatment and different amounts of resin on the physical and mechanical properties of particleboard made from bagasse were investigated. Bagasse particles were treated with 5% hydroxide sodium for 120 minutes. In this research, bagasse (with and without alkali treatment) and Urea formaldehyde resin in three different levels (8, 10, 12 percent of dry weight of raw material) as well as ammonium chloride was used as a catalyst at 2 percent level of the dry weight of adhesive. The results showed that with increasing resin amounts, bending strength, modulus of elasticity and internal bonding of boards increased. The mechanical properties of the particleboards made from treated bagasse were superior to the relevant untreated bagasse. Water absorption and thickness swelling after 2 and 24 hours immersion in water decreased with alkali treatment. Compared with the properties of the boards produced by EN standard, bagasse (without alkali treatment) and the maximum amount of urea formaldehyde resin can be used for general purpose boards (Type P1). But when bagasse is treated with alkali even with the minimum amount of urea formaldehyde resin, it can be used for general purpose boards (Type P1) to be used in dry conditions.

Despite the importance of Arasbaran forests, no dendrochronological research has been conducted in this region, yet. In this study, for the first time, the potential of two juniper species, Juniperus foetidissima and J. oblonga was evaluated to be used in dendroecology. The first and the second species are respectively in the form of trees and shrubs in Arasbaran forests. Twenty-five trees of each species were samples and the sample preparation, ring width measurements, cross-dating, and construction of tree-ring chronology were performed according to the standard procedures. Developed tree-ring chronologies for juniper tree and shrub covered around 60 and 40 years, respectively. The statistics for evaluating the qualities of chronologies i.e. mean sensitivity (MS), signal-to-noise ratio (SNR), and expressed population signal (EPS) proved the capability of both species to study climate-growth relationships and reconstruction of climate. The relations between radial growth and climatic factors showed that both species have similar responses to climate: high temperature before the growing season promoted the growth while a warm spring reduced growth rate. Rainfall before the growing season had no meaningful effect on growth while spring precipitation strongly stimulated the radial growth. Overall, given the good distribution of juniper species in Arasbaran forest, the success of the developing ring-width series for studied junipers and its strong relationship with climate factors, these species can be used for dendroecological studies. For extending the length of tree ring chronology, juniper logs of old local buildings can also be used.

This study aimed to study the effect of using paper making activated sludge, cationic starch and nano-chitosan on physical and strength properties of old newspaper recycled pulp (ONP). For this purpose, the activated sludge was pre-treated for 30 min in 3% furfural and then treated with it in a water bath at 75 and 100 ° C for 45 and 90 min. Afterwards, it was mixed and refined with waste newsprint paper pulp at different mixing ratios. Finally, cationic starch 1.5% and nano-chitosan 2% were added. The test specimens were prepared from pulps with 120 gr/m2 basis weight according to TAPPI standard and the physical and strengths properties were measured and compared. The results showed that the strengths properties (tear, ring crush test, burst, folding strength) decreased and the physical properties (water absorption) increased with the increase of untreated sludge in ONP. Chemical treatment with furfural sludge showed a tangible increase in tear strength, ring crush test, burst strength and folding strength and a decrease in tensile strength and water absorption. Also, the addition of cationic starch and nano-chitosan significantly increased the strengths properties and decreased water absorption of the samples. FT-IR spectrum of the treated samples showed that treatment with furfural strengthen and activate the functional groups on the surface of sludge fibers.The most appropriate mixing ratio of sludge was at 5% level at 100° C, and 90 min.