Journal of Forest and Wood Products
Year:2019 | Volume:72 | Issue:1|Papers Count:8

This experiment was conducted to survey the effect of desiccation and storage temperature on Balkan maple (Acer hyrcanum Fisch & Meyer) seed viability. The seeds were hermetically stored at three moisture content levels (12%, 8% and 4%) and stored in three storage temperatures including-20 ° C (freezer), 4 ° C (refrigerator) and 25 ° C (room) up to 48 weeks in order to record the loss variability in viability. Results showed that the effects of seed moisture contents, storage temperatures and their interactions on seed viability was significant. Seeds were viable (98%) at refrigerator until week 48. Viability at freezer reduced to 80% on week 8 and was constant till week 48. At room temperature, viability sharply decreased from week 24, so that on week 48 all of the seeds (12% and 8% moisture content) were found dead, but the seeds with 4% moisture content had weak viable (18%). This research revealed that Balkan maple seed with 4-12% moisture content can be successfully stored up to 6 months at room temperature and up to a year at refrigerator and freezer. Continuing the experiment in refrigerator and freezer will reveal the storage capability of this seed for longer periods.

This research aims at studying the ability of Mondell pine tree )Pinus eldarica( in decreasing the heavy metal contaminants within the environment by determining the concentration of heavy metals in the leaves and bark of P. eldarica and comparing their concentrations with falling dust. After preparing the falling dust and plant samples, their heavy elements have been extracted by acid digestion method and then measured by flame atomic absorption spectrophotometry. The results showed that the concentration of iron, manganese, zinc, lead, and cadmium in falling dust were the highest to the lowest, respectively. Concentrations of cadmium, iron, cobalt, and nickel, increased with increasing the distance from the road due to multi-directional winds and the presence of other contaminants. The Pearson correlation coefficient among the heavy metals found in the falling dust and Mondell Pine tree showed that the input and controlling factors of these elements in the Mondell Pine tree are probably the same as the dust. The results showed that the P. eldarica bark with the amount of accumulation index of 7261 mg/kg has more ability to simultaneously absorb different metals. As a result, it is expected that significant amount of heavy metals will be absorbed by these trees in the green belt surrounds the Yazd urban area.

By determining the environmental factors affecting the plant species in a particular site, the presence of the species in a site can be predicted, or indirectly, the environmental conditions in a site can be found by species presence. The aim of this research was to study the response of Buxus hyrcana Pojark to some environmental variables individually and to extract its ecological optimum and amplitude in relation to the most important environmental factors by using HOF function. This study has been done in the major sites of Buxus hyrcana in the Hyrcanian forests. 834 sample plots (400 m2) were established by systematic-selective method and within each plot, the presence of this species, topographic factors (altitude, slope and aspect) and some soil variables (soil texture, nitrogen, carbon and pH) were recorded and measured. Fitting the response curve to the environmental variables with HOF function showed that pH, altitude, and clay were the most important predictors on the performance of box tree. The results of this study showed that the response curves of Buxus species relative to the elevation and clay are unimodal and right-skewed, for sand variable, it is left-skewed, for nitrogen the curve is symmetric and for the remaining variables, the response are monotonically increasing or decreasing. The general conclusion based on the ecological optimum amount for each variable showed that the Buxus tree is lime-and moisture-demanding species, which is present in low altitudes, steep slopes and light soils with high nitrogen content. Since more than one factor affects the behavior of species simultaneously, it is recommended that the shape of the Buxus response curve is studied by taking into account the environmental variables in combination and by using other models.

The aim of this study was to provide a multi-factor ecological power model based on the ecological factors of hydrological response units in order to assess the ecological potential of different uses in the Zailakirood Basin, northern Iran. First, by employing ArcSWAT, 608 units of hydrologic responses in 39197 independent polygons were found in the study area. Then, by measuring the hydrological response units using special ecological capability models, the yield of the studied lands was measured in terms of production, quality of vulnerability and management requirements. In the next step, the final vulnerability of the hydrological response units to the degradation caused by the forest utilization was quantified by hydrological indicators. In order to evaluate the hydrologic indices, using the SWAT model, calibration and sensitivity analysis, the effective parameters for runoff and sediment simulation were obtained. In each hydrological response unit, the numerical value of the hydrologic indices was estimated, then the hydrological response units with the capability of producing sediments more than the determined limit of the index was changed to protective and supportive usage. So that, the usage of potential of utilization 1 of forestry and centralized ecotourism capacity 1 remained without changing in the area, potential of utilization 2, 3 and 4 of forestry and centralized ecotourism capacity 2 decreased in the area. Finally protection and supportive function with an area of 14083 ha increased. Since slope, soil and land use have the highest variations in the region and cause the most limitations, application of hydrological response units for classifying the ecological capacity usage and simulating the parameters of management allow quantitative vulnerability assessment is considered as a perfect tool for assessing the capacity of the land.

The present study aims at assessing the effect of canopy combination of beech trees and associated species (beech-hornbeam-maple, beech-hornbeam, beech-maple and pure beech) on the basis of litter and soil characteristics in Mazandaran Province, northern Iran. Litter and soil sampling were taken at each beech stand composition using litter bags and plastic bags (30 × 30 × 30 cm), respectively with five replicates under the canopy of central beech trees. In order to study the effect of different seasons on the presence and activity of fauna, sampling was done in spring, autumn and winter. Characteristics of litter quality (carbon, nitrogen, carbon to nitrogen ratio), physicochemical and biological properties of soil (water content, pH, organic carbon, total nitrogen, carbon to nitrogen ratio, earthworm density and biomass, nematodes and microbial respiration) was measured. The results showed that the total nitrogen of soil (0. 48%) and pH (7. 43), biomass (56. 88 mg m-2) and density (57. 05 nm-2) of earthworm, total nematodes (55. 02 in 100 gr soil) in beech-hornbeam-maple stand was higher than other studied stands. In all of the canopy combinations, density (45012) and biomass (46. 08) of earthworms and nematodes (56. 78) had the maximum activities in autumn while the highest microbial respiration of soil (58. 5) was recorded in summer season. Based on the results, beech-hornbeam-maple stands have a great influence on the soil organic and mineral characteristics. The applied results of this research can be used to select the broad-leaved species for restoring the degraded areas in the north of the country.

Due to the fact that the furniture industry in Iran is mainly composed of small and medium enterprises, cluster development can be used to promote it. This study aimed to prioritize the furniture industry products for eight known furniture clusters in Iran. In the first stage, criteria and sub-criteria of ANP model were identified, and then the decision model was prepared based on ANP in the superdecitions software. After weighing the criteria and the sub-criteria, the results received from questionnaire were used to determine the weight of the alternatives for each cluster separately. The weighting results of the criteria indicated that the most important criterion influencing decision making was the supply with a weight of 0. 46, followed by the sales and product criteria with weights of 0. 31 and 0. 23, respectively. The results showed that in the furniture clusters of Tehran and Islamabad cities, the option of decorative projects is about 0. 35 and 0. 334, respectively. In furniture clusters of Shandiz, Babolsar, Tabriz, and Rudsar, the furniture and office furniture options with the weights of 0. 271, 0. 287, 0. 284 and 0. 293 were the first priority respectively, and in furniture clusters of Qom and Malayer classic furniture with a weight of 0. 32 and 0. 304 respectively. The prioritized results showed that each of the studied clusters has more competitive ability to produce which products.

In this study, the effect of alkyd coatings on the color changes and adhesion strength in parallel and perpendicular to fibers of date palm trees was investigated. For this purpose, the boards with the dimensions of 2 × 7 × 15 mm (parallel) and 5 × 5 × 5 (perpendicular) were prepared. Then, acid catalyzed and nitrocellulose lacquers (SC) and polyester (SP) coatings were applied and all specimens were then transferred to conditioning room (20± 1 º C, and 65 ± 1 % RH) for 15 days. Also, the quality of coatings was evaluated by colorimetric and adhesion strength with pull-off test in parallel and perpendicular to fibers. The results of colorimetric showed that, after coating with acid catalyzed and nitrocellulose lacquers the brightness of the sample was decreased while the redness and yellowness compared to the control sample increased. In addition, coating in the parallel direction caused a greater change in color than the perpendicular direction. Furthermore, the results showed that the color saturation and hue parameters of coated samples compared to the control one were increased and decreased respectively. In addition, the transparency and gloss increases and the color tends to redshow have given. The results of pull-off test illustrated that the adhesion resistance of the acid catalyzed and nitrocellulose lacquers (SC) was less than the polyester (SP) coating and the adhesion resistance in the perpendicular to the fibers was generally 2 times higher than the parallel to the fibers. Increasing adhesion resistance in the cross section than the longitudinal section is due to better penetration of the coating into the fibers of palm, but in the longitudinal section it is due to the separation of the palm tissue.

The current study was carried out to investigate the possibility of improving the strength properties, especially the impact resistance of plastic wood composites (bagasse/polypropylene) by adding the carbon nanoparticles (GNPR) for using in the automotive industry. For this purpose, the nanocomposite must have a low density and high impact resistance. In this research, the 40% and 55 wt% of bagasse particles with 40 meshes, four GNPR content (0, 0. 25, 0. 5 1%), polypropylene (PP), and 2% maleic anhydride polypropylene were used. The nanocomposites were produced by using an internal mixer and then samples were produced for density, impact, and flexural strength test by twostage hot and cold press. The physical and mechanical results showed that by increasing the bagasse particles content in the obtained nanocomposite, the density, flexural modulus, and water absorption of the product were increased while the impact resistance and bending strength were decreased. In addition, by increasing the carbon nanoparticles content the impact strength and flexural strength of the nanocomposite were improved. The SEM microscopic images revealed the uniform distribution of the carbon nanoparticles (GNPR) at the fracture surface of the impact specimens and improved bonding between bagasse and PP particles. Furthermore, by increasing the use of carbon nanoparticles (GNPR), the glass transition temperature of nanocomposites improved. The DMTA results indicated that the modulus of resulting nanocomposite was increases with increasing the bagasse quantity.