نشریه علوم و فنون منابع طبیعی
سال چهارم شماره 2 (تابستان 1388)

Identification of regions having potential occurrence, is one of preparing landslides hazard zonation the basic measures in natural resources management. In this Study, in order to preparing landslides hazard zonation map in Safaroud watershed, by using geographical information system software (ArcGIS9.3), topographic maps (1:25000), field observations and interpretation of aerial photo, basic maps such as geographical map, hypsometry, slope classification, slope aspect, the average annual rainfall, maximum 24-hour rainfall with return period 100 years, the maximum earthquake acceleration and the distance of roads, rivers and faults, is produced. Then using logistic regression method, landslides hazard zonation map of this watershed prepared. The results showed that 52.28 percent area of Safaroud watershed had high and very high classes of hazard, and that located on formations content layer of silt stone, sheyl, sandstone, conglomera and coal, on Slope from 15 to 35 degrees, close to roads, rivers and faults and in the average of elevation (1000 to 1500 meters asl.) that have large amount of rainfall (more than 850 mm).

Dead woods are importance in forest sustainable management and have a significant role in conservation of forest biodiversity and regeneration. They have affect conservation of nutriment material and recycling of nutriment elements. Other functions of dead woods effect on forest product potency, different formation slope Geomorphologies and floodway. considering management of forests that on synchronous with nature management method superintendence, not enough data, in this study endeavor recognition voluminosity schema dead woods types in virgin forests on the ground of indicator of this site for use forest managers for conservation of biodiversity and sustainable management. This study done in permanent survey plot of Shast- Kollate forest with 16.9 hectare and with census inventory method. Result shows in this virgin forest, the dead wood mean volume was 66.81 m3/ha and the percentage of dead wood that was sang 63 and remain dead wood was standing that was 37% formation. Ratio of dead wood volume on Living Wood volume 0.13 determined. Density of dead wood 25.56 n/ha that maximum proportion was for beech with 46.58%. Results, in comparison with other studies in Iran and European beech (Fagus Sylvatica) forests and reduce site product potency.

In order to investigate the effect of slenderness coefficient (SE) on growth characteristics of Quercus castaneifolia seedling, the seedlings with small SE (52 ± 20) and big SE (133 ± 42) were planted as completely randomly design in a degraded plain forest. The results of independent-T test indicated that at the end of second growth season, survival rate of seedlings with small SE (%82) and big SE (%58) was differently significant. The seedlings with small SE had greater increment in collar diameter, stem length and apical shoot than those with big SE. It can be deduced that Q. castaneifolia seedlings with small SE have higher ability to absorb nutrient, due to their bigger collar diameter and stronger roots. Therefore, Q. castaneifolia seedling with small SE can be useful for reforestation in Northern forests of Iran.

In this research, beech (fagus orientalis ) lumbers at 5 cm thickness were rondomically selected and commercially cut down from sari region(Neka choob company), with three schedule namely T5-C3, T5-C4, T6-C4 were adapted for drying the lumbers down to the final moisture content of 8% to evaluation the effect of kiln schedule on warp and surface checking. primary dry bulb temperature each three schedules was adjusted at 49 °C and the final dry bulb temperatures was adjusted at 71 , 71, 82°C respictively. Basic specific gravity and dry specific gravity were measured 0.52, 0.61 respectively. Longitudinal, radial, tangential and volumetric shrinkage were measured 0.46%, 5.8%, 10.2%, 16.46% respectively. Quantity of defects including crook, bow, twist and three longest surface checks of the lumber were measured before and after the drying process in each stage. In order to analysis the lumber defects for estimating the best schedule, quality control graph were used. In the end, results of investigation indicated that drying of beech lumber by using of the three schedules was desired. However the third schedule (T6-C4) had better drying characteristics than the other schedules.

In this study the important mechanical properties of the particleboards produced from kiwi pruning particles and industrial wood particles were investigated. For this the effect of the mixing persentage of the Kiwi prunings and the industrial particles (four levels: 10 to 90, 20 to 80, 30 to 70 and 40 to 60 percent respectively), press time (two times: about 4 or 6 minutes) and hardner content (two contents: 1 or 2 percent) on the mechanical properties of produced boards were studied. After manufacturing the experimental boards, their mechanical properties were measured, according to DIN-68763. Results showed that adding up the kiwi particles to the industrial wood particles to 95 persent has not any significant effect on modulus of rupture (MOR); however the highest modulus of elasticity (MOE) in boards was obtained while using 40 percent kiwi particles in mixture. By increasing in adding up the kiwi particles from 10 to 30 percent, the internal bond (IB) decreased, but it was increased while the kiwi particles rose to 40 percent. Results indicated that the boards made by employing 6 minutes press time and 2 percent hardner, benefited from a higher MOR and IB than boards made using 4 minutes press time and 1 percent hardner. In general, results showed that adding up the kiwi particles to the industrial wood particles caused to improve some of the mechanical properties of particleboard.

In this study, has been investigated specific modulus, radial and tangential shear moduli as well as the specific gravity in timbers from Iranian beech were measured, using free vibration on a free-free bar and their effects on quality and damping factors. Sampling was done in accordance with ISO3129 and the non destructive evaluation was followed using the system of ndt-lab on 26 clear and mc stabilized specimens. As it could be predicted, there were no significant differences between radial-longitudinal and tangential-longitudinal vibrations to evaluate the longitudinal modulus of elasticity. Meanwhile there were no significant differences between radial and tangential damping that could be defined due to radial and tangential relative homogeneity in such a diffused porous species. Comparisons between specific modulus and damping factor showed a power correlation. Such power correlation was also observed between acoustical coefficient and damping factor. None of shear moduli or elasticity modulus individually had significant effect on damping but to optimize the vibration properties of these timbers and decreasing the damping one must find a solution to increase the acoustical coefficient and specific modulus. On the other hand this concept could be followed by increasing the modulus of elasticity or decreasing the specific gravity.

In this study, investigated the effect of type and lignocellulosic filler content on the mechanical properties of biocomposites made of agricultual wastes and biodegradable polymer. For this case, wheat straw and powdered beech separately mixed with polybutylene succinate (CPBS) at four level weight of 10, 20, 25 and 30 percent in a HAAKE set. Test specimens were made through injection molding method. The tensile, notched impact and hardness strength of laboratory biocomposites were evaluated by ASTM standards. The results showed that between two types of lignocellulosic filler, maximum strength and modules were applied in powdered beech specimens, whereas, the composite with wheat straw had maximum hardness and notched impact strength. With increasing content of lignocellulosic filler in matrix, strength, modulus and hardness increased and elongation at yield and notched impact strength decreased. The simultaneous effect of type and percent of lignocellulosic fillers on the mechanical properties showed that the biocomposites from 30 percent of powdered beech had optimum performance and the specimens from 10 and 30 percents of wheat straw had maximum hardness and notched impact strengths respectively.

In this study, the effect of site index on biometrical and physical properties of populus wood. For this reason, three regions of Malayer, Shazand and Borujerd in Markazi provience were selected ,and the characteristics of each region such as soil type, geographical direction and climate coditions were determined. In each region, 5 normal populus nigra species were selected and from each stand on specimen ( totally 5 samples) in breast hieght prepared and transferred to the laboratory. Then, biometrical characteristics: Fiber length, fiber diameter, cell wall thickness and physical properties in cluding: Dry-density, critical-density and volumetric shrinkage were measured. The results showed that, site index has significantly effect on all biometrical and physical properties of populus wood in 95% confident levels. Also Borujerd site as mentioned to biometrical and physical properties has highest value compared with Malayer and Shazand sites.

Solid waste land fill has constantly been considered as one of the basic problems for attendants of city services. The environmental living and healthy perils of solid waste land fill due to relation with the life of human being require control and specific application of managing system will be more complex in development and population growth. In respect of the problem erroneously driving away of rustic solid waste land fill in kojor area, Nowshahr, and decreasing of various results, in addition due to the area being touristic basically site selection has been regnired. Nevertheless, Geograplic Information System (GIS) has been used with taking into consideration of environmental living standards to choose a suitable plance for solid waste landfill. In this study topology, land steepness, soil quality, geology and geological structure, hydrology and hydro geology, the farness from flowing water resources, rustic population center, available paths, producing center of solid waste land fill and using a statistical method have been the main factors in site selection for solid waste landfill. Suitable places have been provided on the basis of priority on the map, based on final analysis results and determining acceptable area.

Iran has desirable plant species variety due to it,s echological diversity ; so, has an important situation in global biodiversity. This variety has led to unique attractions for tourism as an outstanding universal values. In regard to the effect of tourism on conversions of ecosystem conditions, can effect on various biodiversity indices. As a result this study paid on this case in Namak Abroud frosted tourism region. For this aim the study area based on tourism abuses, divided into 2 zones including: Low-tourism pressure and High-Tourism pressure. In each zone ten sample plots with an area of 100m2 and two microplots and area of 4m2 had been selected systematical random for concentration of woody and vegetative species, and at the same time in every sample plot, also soil sample plots were collected. In order to compare and test the variety between two zones various biodiversity, reachness and evenness indices has been used and in order to compare the meaning ful average indices. T-test is used. The collected soil samples were analyzed in lab to examine the physical qualities. The results has shown the rate of variety indices in Low-tourism pressure zones is more than High – tourism pressure zones the soil humidity in Hightourism pressure zones was extremly influenced by tourism, and growth coudition was under its negative effect. Overall that High-tourism pressure has significant effect on decreasing little material, soil humidity, number of plants species, reachness, diversity, increasing soil density and evenness index.