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Issue Info: 
  • Year: 

    2018
  • Volume: 

    26
  • Issue: 

    1
  • Pages: 

    209-218
Measures: 
  • Citations: 

    0
  • Views: 

    340
  • Downloads: 

    0
Abstract: 

KuhSefid Flourite deposit is located about 110 km south east of Mashhad. Geological units of the region related to Kashafroud Formation with Jurassic age. Most of fluorite mineralization can be seen along the faults with direction of north west-south east. Fluorite veins are differente in diameter of 2 to 2. 5 m and length of 50 m. Hydrothermal solutions with maximum and minimum temperatures of 181⁰ C and 125⁰ C with the average temperature of 152⁰ C in protraction of faults, cracks and fragments, have created mineral substance. Geological evidences, petrography, mineralization and homogeneous temperature of fluids inclusion, are the evidences that concluded the Fluorite mineralization as Epithermal.

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Issue Info: 
  • Year: 

    2022
  • Volume: 

    24
  • Issue: 

    2 (117)
  • Pages: 

    101-118
Measures: 
  • Citations: 

    0
  • Views: 

    167
  • Downloads: 

    0
Abstract: 

Background and Objective: Porcupine (Hystrix indica) is the largest rodent found in Iran and causes a lot of damage to protected areas and forest plantations every year. Material and Methodology: investigation of the environment and damage to trees in Sefidkouh forest of Doureh Chegini city of Lorestan province was performed using transect method and marking damaged trees between 2011-2015, which finally, damage to damaged trees with different criteria and characteristics were determined. Also, three conventional methods of fencing, hedging and crimping were used to control the porcupine damage. Findings: The study of porcupine damage to trees showed that it had an increasing trend during the years under study and among the existing tree species (Persian oak, fig and almond) only oak trees were damaged. The highest damage of porcupine was observed in spring on trees with a diameter class of 25-50 cm. Also, the most damage to tree trunks was observed at a height class of 40-60 cm, and the thickness of the bark of tree trunks fed by porcupine was between the two classes of <1 cm and 1-1. 5 cm. Among the direct and indirect damages caused by porcupine, peeling the tree has caused the most damage to the stems. The results of Spearman correlation between the variables of degree of damage with tree form, diameter class, bark thickness, time of damage showed a positive and significant relationship between the degree of damage caused by porcupine to Quercus brantii trees with diameter class, time of damage and there was negative and significant relationship between the degree of damage with the thickness of the bark and the form of the tree. The results of mechanical control of the porcupine had significant difference in the three methods of hedge fencing and crimping, so that the fencing method was effective in controlling this rodent. Discussion and Conclusion: Porcupine causes damage to oak trees, especially in the protected areas of Zagros forests due to the conservation and protection conditions of these forests and mechanical control methods are effective in controlling the damage of this rodent.

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Issue Info: 
  • Year: 

    2018
  • Volume: 

    8
  • Issue: 

    18
  • Pages: 

    83-102
Measures: 
  • Citations: 

    0
  • Views: 

    626
  • Downloads: 

    0
Abstract: 

Selseleh and Delfan counties located in the North and North West of Lorestan are very important with having Sites and remains of Parthian period. Abundance and dispersion of these Sites is the demonstrative of this area in Parthian period. The studied area is located in the divide of Sefidkouh and Garrein which is a part of central Zagros and its environment appearance includes Valleys, Mountain plains and mountainous with a land – measurement amount to 4000 Km square. According to Archaeological studies and surface data there have been found about 519 ancient monument and sites from Paleolithic to recent Islamic period in this area which 307 of them had remains of Parthian period. Although a number of temporary Sites are probably nameless. Dating of These Sites is generally accomplished based on the surface data (Clinky-painted – glazed and simple) and acquired results from archaeological studies allude to Parthian settlements and their different living methods that it can be acquired very important documents to reconstructing economic and living methods of their aboriginal according to digging in the main Sites. In addition, in the present paper, it has been attempted to address several questions including: how have the settlements been distributed during the Parthian period in these regions? What could have been the reasons for the increase of Parthian settlements compared to the previous and later periods in these areas? How can the lack of large-scale settlements of the Parthian period in these regions be explained? Dispersion appearance of these ancient Sites also indicates that the most of the settlements in this area have been in the form of relatively small rural units. Although in this area there are not any evidences of urban centers – but acquired results from the study demonstrates the continual and effective presence of Parthians in the area.

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Issue Info: 
  • Year: 

    2024
  • Volume: 

    12
  • Issue: 

    1
  • Pages: 

    63-72
Measures: 
  • Citations: 

    0
  • Views: 

    14
  • Downloads: 

    0
Abstract: 

Extended Abstract Background: Sustainable management and fundamental planning of forest resources require efficient and high-quality information about the current and future states of forests. Investigating the current and future states of forest stands, describing the structure of the forest stand, and the response of the stand to tending operations are among the capabilities of statistical distributions in forest management. Frequency distribution modeling is the distribution of people in a population in different classes. Since natural phenomena include continuous and discrete types, their distribution will also be different and diverse. The use of statistical distributions in the forest has a long history, and some researchers have considered its history as long as two centuries. Zagros forests, as one of the most important vegetation areas of Iran, have a special importance from the socioeconomic and ecological points of view. The dominant species of these forests is the Iranian oak (Quercus brantii Lindl). According to geographical and environmental conditions, this species has various habitats in the vegetation zone of the middle Zagros. It is expected that this species has different probability distribution functions in different habitats. Therefore, the probability distribution functions of the characteristic height in habitats with different vegetative structures of Iranian oak in the forests of Khorramabad city were investigated in this research to select the best models in different habitats. This study also seeks to provide useful information on the authority of forest managers and planners to preserve and improve these valuable forests. Methods: To carry out this research, two areas with different structures, including coppice with standard (Sefidkoh area) and standard with coppice (Qala-Gol area) were determined in the forests of Khorram Abad city through numerous excursions in the forest. A forest stand with an area of approximately 3 ha was selected in each of these areas. This forest stand was chosen in such a way to represent the forests of the region. The subsoil was semi-deep and north direction in the Qala-Gol forest stand at an altitude of 1850 m above sea level and with an average slope of 20%. In the SefidKoh forest stand, the subsoil was semi-deep and located in the north direction at an altitude of 1900 m from sea level with an average slope of 30%. In each of these two selected forest stands, the height of all Iranian oak trees, with a height of > 1.5 m, was counted 100%. In total, the heights of 458 and 348 Iranian oak trees were measured in the two SefidKoh and Qala-Gol regions, respectively. A TruPulse 360 laser device was used to measure the height of trees. To investigate the distribution of height classes, the most widely used continuous probability distribution models in biological research were used due to the continuousness of the height variable, including two-parameter Weibull, two-parameter gamma, normal, log-normal, beta, and Johnson. The goodness of fit of the data was also examined using the Anderson-Darling test, which has a higher power than other tests. Easy Fit 5.6 software was used to analyze all data and draw graphs. Results: The statistical errors were 4.45% and 2.82% in the Sefidkoh and Qala-Gol regions, respectively. The average height of trees was 6.76 m in the Sefidkoh region (between 1.8 and 18 m) compared to that of 7.54 m (between 1.53 and 14.04 m) measured in the Qala-Gol area. The values of skewness and Kurtosis were positive in the two forest areas, with higher values in the Sefidkouh region than in the Qala-Gol area, indicating the concentration of data in lower-height classes in the Sefidkouh region. The results of Anderson-Darling's goodness of fit test in the Sefidkoh area (coppice with standard) showed that the most suitable probability distribution functions (with a 5% error level) for modeling the distribution of trees in height classes were Johnson sb and beta, respectively. In the Qala-Gol region (standard with coppice), the most appropriate distribution functions were identified as beta and normal, respectively. Conclusion:  The results of this research show that the forest has an uneven-aged structure in the areas where the oak forest has a coppice with standard form, according to the form of distribution (decreasing distribution). In contrast, the forest has moved toward a single-stemmed and even-aged forest in areas where the forest form is standard with coppice. This is mainly caused by the destruction through grazing, the cutting of branches for livestock and fuel consumption, and the indiscriminate use of byproducts that have occurred in this region. In the Sefidkoh region, the effects of destruction and less human intervention were observed at the regional level in field observations. According to the shape of the distributions obtained in the two sites, the vegetative forms of the trees affected the distribution functions of their heights, which can provide useful information for managers, planners, and researchers to maintain and control these valuable forests.

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