Journal of Renewable Natural Resources Research
Year:2018 | Volume:8 | Issue:2 (SERIAL NUMBER 28) |Papers Count:7

The efficiency of motor-manual groups in process of felling trees is less than expected in some utilization groups, which indicates the needs for improving the performance of these groups. The first step of the efficiency improvement is the evaluation of the current status of these groups. In this study, the felling groups were randomly selected in 12 gropes from the forests of West Mazandaran. Each group included 2 and 3 operator (a total of 24 groups). The characteristics of each group (the number of people, system cost, chainsaw hours-of-operation and the cutting wood volume) were collected for three working days. The required diagrams (number of felled trees, the cutting wood volume, system cost, hours of operation and chainsaw hours-of-operation) were prepared and investigated by GAMS software. The number of people, system cost, chainsaw hours-of-operation as well as the cutting wood volume was designed as input and output variables, respectively. The data were also analysed through data envelopment analysis (DEA). The DEA results indicated that the effectiveness of managerial, technical and inductive were 0/9215, 0/8016, and 0/8671 respectively.

Due to effects on biological processes, deadwoods play an important role on sustainable forest management including biodiversity conservation, forest regeneration, increasing nutrition and nutrition cycle. The aim of this study was to evaluate deadwood effects on biodiversity in Makaroud forest management plan in Jisa and Shahrestan forests. Therefore, the species, diameter, decay degree and slop for each sample were recorded and 90 deadwoods were selected in 3 different heights above sea levels. Biodiversity was evaluated by using Simpson, Shannon Weiner indices as well as species richness index using Margalef, Menhinik indices and evenness index by Hill index. Results showed that biodiversity indices in 150-300 m height above sea level were more than other heights. However, margalef index was lower in 1800 m height than 1000 m and 150-300 m height, and Hill evenness index was higher in 1800 m height than 1000 m and 150-300m. It can be concluded, the diversity index will be decreased, and evenness and richness indices will be increased by increasing height from sea level. There is significant correlation between diameter and height of deadwoods with plant species indices.

Various methods have been suggested for locating areas for ecotourism development by different researchers, which have different strengths and weaknesses according to the conditions of the region. Obviously, using quantitative methods and reducing expert interference in the decision making process and evaluation can provide better results. Therefore, in order to evaluate ecotourism development, a multi attribute evaluation method based on fuzzy logic and hierarchical process (AHP) has been used. For this purpose, one of the northern forest areas of the country that has various capacities in the field of ecotourism, such as the Kelardasht forests, was selected and studied in the region. At first, ecological criteria and indicators were identified and quantitatively and normalized by fuzzy method. Also, the weight of the indices was determined by hierarchical analysis method(AHP) then, using Weighted Linear combination(WLC) method all the information layers were combined and the ecological potential of the area was mapped for ecotourism. The results show that the WLC is the suitable and efficient method for locating recreational areas in the study area. Because the simultaneous use of fuzzy logic and the AHP method for determining the weight of the indices provides one more logical condition for evaluation lands by the WLC method. Meanwhile, in this method. One of the most important results of this study is the effect of forest condition on ecotourism demand. Also, road construction in the region has attracted visitors from the region and has led to an increase in demand for ecotourism. On the other hand, forest and environmental degradation will reduce demand for ecotourism in the area.

In this study was purposed to investigate the absorption of zinc by Acacia victoriae. The one year old shrubs were randomly selected in 3 replications and exposed by Zinc-sulfate in four concentration (0, 50, 250, 500 mg/l). Some of the morphological and physiological properties such as plant height, collar diameter, leaf number and area, green and dry weight of plant, tolerance index, grade of growth inhibition and chlorophyll content as well as bioaccumulations of Zn in different plant tissues were evaluated. Results showed that the properties were significantly affected by Zn. However, the effect of high concentration of Zn slight had as well as tree on effects series any have didn't that, properties the in decreasethe signs of toxicity with zinc, addition In. observed not was the amounts of accumulation of Zn in the roots were higher than aboveground tissues, so that about 80% of Zn (4794. 5 mg/kg), more than 13% of Zn (797. 9 mg/kg), and about 7% of Zn (488. 35 mg/kg) were accumulated in the root tissues, the stem tissues, and the leaves, respectively. The bioaccumulation and transfer factors were also measured to higher one and lower one, respectively. Generally, the result demonstrated that the Acacia victoriae could be affected as a phytoremediation in reduction of soil pollution to Zn.

Changes in the land-use pattern has affected hydrological processes in the watersheds and disrupted the natural balance of water flow. In the present study, changes in hydrological components of Amameh watershed as a result of land-use changes from1988-2013 were studied. Due to lack of the land-use map in past years, the land-use map was prepared and analyzed by Landsat TM satellite images in the ERDAS Imagine software in 1988. Furthermore, the available information were used to provide land-use map in 2013. Land-use maps of 1988-2013 were prepared using ArcGIS software. In existing maps, six land-use classes; class 1, 2, and 3 rangelands, agricultural and garden, arid land, and river-bed were designed. The results showed that Amameh watershed was affected by severe changes in the land-use during the study period, so that the class 1 rangelands to class 2, class 2 to class 3, and even arid land were changed. In addition, the residential areas (villa) were increased from 2. 5% in 1988 to 8. 4 in 2013. The HEC-HMS model was used to investigate the effect of land-use changes on the hydrological flood hydrograph of Amameh watershed. The results of hydrograph study of 1988 and 2013 showed the volume increase of runoff and peak discharge rates during the 25-year period, and also the watershed runoff coefficient was increased from 0. 82 to 0. 89.

The aim of this research was the introducing a method to convert technical data of logging operation damages to economic value to express the investment for improving logging operation. This study was carried out in parcels 228, 231 and 232 in chafroud shanderman watershed-Guilan. After selecting the sample trees, the condition and quality of residual trees after felling and skidding were investigated. The technical data to converted then werethe economic value (Rials) using opportunity missed and replacement cost methods. The market value of different wooden products was used to measure the value per cubic meter of extracted wood in the Caspian forests of Iran. After that, felling and skidding average cost per cubic meter was subtracted from wood value. The results indicated that selective cutting can damage the residual trees to value of 947385000 Rials (6072981Rials/ha) due to the forest logging operations. Therefore, the current logging operations also need to be accompanied with careful monitoring by operation personnel and investigated the site status after the logging operations.

Contamination of seafood products to pathoges like Listeria is a for consumers. The aim of this study was to evaluate the field prevalence and typing of Listeria monocytogenes in the local fish market of Shahr-e Kord, Iran. Antibiotic susceptibility of the isolated Listeria was also carried out by the antibiotic disc diffusion method using 13 different antibiotics. A total of 100 rainbow trout were randomly collected from retail market in Shahr-e Kord for examination of the prevalence and typing of Listeria species using biochemical methods. Four isolates of Listeria were identified; One isolate of L. inovaii and 3 islolates of L. monocytogenes. All four isolates showed the highest antibiotic sensitivity (100 % susceptibility) to five antibiotics including cotrimoxazole, tetracycline, gentamicin, erythromosine, and vancomycin. However, all strains showed resistance to oxacillin. As L. monocytogenesis is of the most important pathogens in humans, fish contamination to different species of Listeria could be a potential risk and requires more attention.