نشریه علوم و فنون منابع طبیعی
سال هفتم شماره 2 (تابستان 1391)

Quantitative evaluation is an important issue of soil erosion assessment in a watershed basin by which we can plan to solve the existing problems more carefully. Azadrood Watershed, that is located approximately 12 km away from Nashtarood, having 32- year (56-88) sediment survey statistics in its output is a suitable area to evaluate erosion and sediment experimental models. We have chosen this area to assess sediment through common methods, and compare the values obtained. Therefore, we can attain the best model for estimating the erosion and sediment rates. In this study initially we have used basic information (lithology - topography and etc.) The area was divided into 4 units and 41 subunits and all the factors needed to estimate erosion and sediment through the two methods EPM and MPSIAC (using ARC GIS) were applied for them. After that, the amount of deposition manufacturing at the sediment survey station using the existing measurements of flow and suspended sediment was determined. The amount of sediment by the methods of MPSIAC and EPM was respectively,1.8 and 2.3 times the deposition measured in the gauging station. Finally, the values obtained from the models revealed that the MPSIAC method shows the minimal difference and error with the measured sediment in the deposition survey station.

Cadmium is one of heavy metals which causes high toxicity. In addition, it can be accumulated in plants and make anatomic changes in them. Finding out these changes in industrial woody plants exposed to various extends of cadimum are important, as anatomical changes have direct effect on wood quality and quantity. Therefore, in this research we investigated the effect of different soil cadmium concentrations (0, 30, 60, 120 mg/ kg soil) on anatomical characteristics of leaf in Quercus Castaneifolia such as stomatal density and stomatal pore length. The experiment was performed in completely randomized design and each treatment was replicated 5 times. The results showed that the used cadmium levels had no significant (P<0.05) effect on stomatal length and stomatal density. Therefore, it can be concluded that the concentrations of cadmium used were too low to change the anatomical characteristics of leaves in mentioned seedlings.

The purpose of this study was to investigate the influence of tree canopy density, DBH (Diameter breast height), vertical crown classes (upside, amid and beneath), physiographic factors (elevation, aspect and slope) on mistletoe infection intensity in central Zagros forest ecosystems in the north of Ilam, Bankol region (approximately 120 ha). For this study, random systematic method and 62, 1000 square meter plots were selected. Results showed that foothill direction had significant effect on infection intensity, while elevation and slope percentage hadn’t any effect of infection. Most numbers of mistletoes was in southern direction. Results also showed that vertical crown classes had significant effect on infection and upside crown had high infection both for Quercus brantii and Acer monspessulanum. Maximum infection intensity was in region with canopy opening innuendo 0-25%.The results indicated that most infection has happened in middle DBH classes namely 30,35,40.In this region Quercus brantii and Acer monspessulanum with 80% and 16% have had most shrub numbers of mistletoe.

Genetic diversity is important for long time survival of poplar cultivations and will increase their adaptation against environment changes. Therefore, in order to adopt strategies for conservation and development, it is necessary to estimate the amount and distribution of genetic diversity in existing populations of poplar. In this study, for estimating genetic diversity between and within 7 stands of Populus alba established in Esfehan and Zanjan provinces, morphological traits were measured. In order to assimilate environmental conditions, cuttings were planted under randomized complete blocks design with 3 replications. In the middle of growing season, 17 morphological traits were measured and data were analyzed using analysis of variance, t-test and cluster. Results showed significant differences observed between stands. By using cluster analysis, stands were classified in 2 groups on the base of 2 different provinces. Results showed that in homogeneous conditions, morphological traits could reveal diversity and similarity in poplar stands.

In this study the effect of type of overlay on the flexural properties of particleboard (Pb) and medium density fiberboard (MDF) was investigated. For this purpose, Pb and MDF panels with density of 660 and 760 Kg/m3 respectively were supplied by Pars Neopan mill. Then panels were overlaid with beech veneer and melamine laminate and were compared with unlaminated panels. Samples were prepared from the panels by 16×50×370mm dimensions according to ASTM D 1037 while they were equally and longitudinally cut. Static bending tests were performed. The results showed that flexural properties in MDF were better than Pb panels. Type of overlay and direction of panels influenced flexural properties. Furthermore, the results indicated that the veneered panels and parallel direction in panels showed higher bending resistance.

In this study, possibility of particle board production, using residual sunflower seed barks that remains after oil extracting process was investigated. for this purpose, after chemical composition determination, the experimental boards were produced by using urea formaldehyde resin at two levels (8, 10 %) and hardener at three levels (0.5, 1 and, 2%). Mechanical strengths, such as bending strength, modulus of rupture, internal bond and water absorption (after 2 and 24 hours) were investigated. Results show that the amounts of resin and hardener had significant effect on all experimental mechanical and physical properties. Regardless of some minor exceptions, the best production condition were achieved by applying 10% resin and 1% hardener.

In this study, the possibility of using educational office waste papers instead of all or a part of CMP pulp of Mazandaran Wood and Paper Industries (MWPI) was investigated. For this purpose, in addition to preparing initial pulp from educational office waste papers in MWPI laboratory, hand sheets were made from it and its optical and strength properties were measured according to TAPPI standard. Then this pulp was repulped with the following conditions, time: 15 min, temperature: 60oC, consistencies: 0.5% and Na2SO3 chemical. At the beginning a pure pulp was used and then with 15%, 30% and 45% of purity was mixed with CMP pulp of the mill, and from each sample, a hand sheet with 60 gr/m2 basis weight was prepared. Next, the initial pulp was deinked under %1 consistency, 15 min time, 45oC temperature, %2.5 sodium silicate, %0.5 surfactant and %5 Na2SO3. Optical and mechanical properties were measured, and statistical analysis was done by using mean comparisons. All properties improved in comparison the control sample (pulp mill) with Na2SO3 pulping and deinking. All properties improved in Na2SO3 deinked pulp and while with the MWPI pulp mill, too. The results showed that from all treatments, Na2SO3 deinked waste papers have better properties for newsprint production.

According to the role of tourism on various biodiversity indices including diversity, richness and evenness and its impression on biomass and the abundance of creatures living in the area especially earthworm, we have decided to do the present survey considering this issue in chaldare natural forest park for this purpose we divided the area into 3 different zones: low-tourism pressure, mean tourism pressure, and high tourism pressure. After identifying the zones under study we started vegetative sampling. In each zone we chose 5 samples with an area of 100m2 with square shape in square (10×10m) which was randomly and systematically selected then the diversity of wood and seedling species was investigated. In four corners of each piece of land we chose some Micro-plots in 2×2m as big as 4m2 to study the biodiversity of each woody species. Moreover to measure the earthworm biomass in the center of each Macro- plots, a small plot in 0.5× 0.5 m for the earthworm biomass was prepared and the humus weight in the area unit was assigned through harvesting some soils from the surface area. Collection of soil Macro phones was done manually. Then to remove the humus layer we had to do it in some holes as big as 25×50×50cm and then we analyzed them in Lab. The results showed that high-tourism pressure has significant effect on decreasing plant species also making less diversity, increasing evenness and less richness in vegetarian coating, however it didn’t have any effects on trees and seedlings diversity. for sure the reasons would be their ages, high survival, roots perseverance and being less sensitive to tourism pressure in addition to destructive factors. Moreover, the high-tourism pressure could cause ecosystem destruction, soil squashing and density. It didn’t statistically show any significant difference and didn’t have an effect on earthworm biomass.

Ecotourism is a kind of obligatory trip to enjoy natural attractions. Dodangeh wildlife refuge is remarkabley potential for developing ecotourism because of its specific natural situation and a wide variety of fauna and flora. The purpose of this study is to establish an ecotourism management plan and to present strategies to develop ecotourism in this region. Therefore, the most strength, weakness, opportunity and threat points were identified. Then strategies were determined through SWOT method and were scored by using QSPM matrix and the were prioritized. four items of prioritized strategies are listed below:1- WO6: Budget request for allocation of credit in order to develop required infrastructures for developing ecotourism in the area.2- WO2: Promoting public awareness in order to introduce the Dodangeh refuge through appropriate publicity.3- WO5: Presenting health, welfare and residential services such as publicbathrooms, rubbish bins and gazebos, etc. at attractive places in the refuge.4- WO7: Creating job opportunities for local communities through developing ecotourism in this region. Finally some suggestions were presented to use optimum strategies for ecotourism management of Dodange refuge.

According to that the most of Iran is of arid and semi arid rangelands, it is necessary for the plants for this region to be tolerant to drought. Use of draught resistant rangeland species is essentioal for reforming and developing rangelands. Dactylic glomerata species is an important perennial grass for pasture and forage production. Because of the importance of this species in the rangelands and its tolerance to draught; therefore its amount of resistance to drought stress and its effect on germination, radicle length and Plumble length. of Dactylis glomerata from two regions Karaj and Bijar respectively was tested. For creating different potentials of dryness polyethylene glycol (PEG 6000) was used. This study is a factorial design research based on completely randomized design with 4 repeat and 5 drought treatment including (0, -0.2, -0.4, -0.6, -0/8 MP of PEG). The results showed that germination rate, germination percentage and plumble length of the Bijar varieties are more than Karaj varieties. In sum, the seed of Bijar region showed to be more tolerant to drougth than the seed of Karaj region.