List of articles (by subject) Forests and natural resources


    • Open Access Article

      1 - Spatial patterns of trees and height story competition over forest developmental stages in the mixed stands of Guilan
      Maryam Kazempour Larsary Kambiz Taheri Abkenar Reza Akhavan Hassan pourbabaei
      Spatial patterns of trees and their interactions specifically reflect mortality, gap creation, resource use, and also determine population dynamics such as seed dispersal, understory development, initial survival and establishment, growth, and competition. In this study More
      Spatial patterns of trees and their interactions specifically reflect mortality, gap creation, resource use, and also determine population dynamics such as seed dispersal, understory development, initial survival and establishment, growth, and competition. In this study, three one-hectare sample plots in the three stages of early development, maturity and decay were selected in an untouched mixed beech forest in order to consider competition of trees from different height stories along developmental stages and all trees with a diameter at breast height (DBH) larger than 7.5 cm by species were measured based on chest diameter, height and determination of cartesian coordinates using distance-azimuth method. Then, these stems data were first divided into three groups (lower, middle and upper stories) depending on their location in the vertical strata. The spatial patterns and spatial associations were analyzed among different tree height classes using univariate and bivariate Ripley’s K-function. Results showed that spatial pattern varied with canopy strata and scales in different development stages. Positively spatial associations of Fagus orientalis at upper and lower stories in initial and optimal staged and also among F. orientalis at upper and middle stories in decay stages influenced by shade-tolerance characteristics, seed dispersal limitation and the role of larger nurse trees as a shelter of small trees. Competition for resources was observed between Fagus orientalis at the middle story and Carpinus betulus at upper story in the all development stages. Recognizing spatial pattern and natural events guided by nature over time are necessary to carry out targeted forestry operations and In proportion to the evolutionary stages of forest stands. Manuscript profile
    • Open Access Article

      2 - Detection and prediction of forest level changes in Guilan province using satellite images and geomod model
      sahar abdollahi Vahid Nasiri
      Following the rapid economic and social development in recent decades, human activity to use natural resources has been reflected in the form of infrastructure and agricultural activities. This has severely affected forests as an important ecosystem which are considered More
      Following the rapid economic and social development in recent decades, human activity to use natural resources has been reflected in the form of infrastructure and agricultural activities. This has severely affected forests as an important ecosystem which are considered potential environmental resources for future evolution. The purpose of this study is to detect changes of Guilan province forest levels during a period of 20 years (1996-2016), also modeling and predict these changes for the next 15 years using the geomod model. Landsat TM and OLI sensor images were used to prepare land use maps for 1996, 2006, and 2016 periods. Satellite images were classified into forest and non-forest classes using the maximum likelihood method and multiple educational samples. The geomod model was simulated based on the changes made in the period 1996-2006, changes in forest cover using the variables of height, slope, direction, distance from residential, distance from a road, distance from forest, with implementation for 2016. The predicted validation results of the forest cover map in 2016 is indicator the overall accuracy and value of the kappa index equal to 94.19% and 0.9159, respectively. Based on the results of detecting changes during the study period (1996-2016), 1054.97 hectares of forest area in Guilan province has been reduced and with the continuation of this trend and stable conditions in the next 15 years until 2031, another 871 hectares will be reduced from its level. Given the importance role of Hyrcanian forests, it is necessary to conduct multi-time studies to monitor and detect changes. Obviously, the information from such studies can be used in managerial and strategic planning. Manuscript profile
    • Open Access Article

      3 - Studying the Spatial Distribution Pattern using Distance and Quadratic Methods in the Zagros Recreational Areas
      koroush nazarpoorfard Hassan pourbabaei
      Studying the spatial pattern in plant communities is necessary for understanding the many issues in forest ecology and management. The purpose of this study is investigating the effect of recreation on Spatial patterns of trees in Zagros oak forests. Sampling methods we More
      Studying the spatial pattern in plant communities is necessary for understanding the many issues in forest ecology and management. The purpose of this study is investigating the effect of recreation on Spatial patterns of trees in Zagros oak forests. Sampling methods were fixed-area plots and T-square methods. In each region, there are 40 sample plots and 40 sampling points were taken to measure the distances in the distance method in each region. To quantify and analyze the distribution patterns in the sample method, Green, Morissita and Standardized Morisita indicators were used and The Hopkins, Eberhardt, Heinz, C, Johnson and Zimmer indicators were used in the distance methods. C, Hopkins and Heinz indicators showed a clumped pattern in the area. But the Johnson Zaimer and Eberhart indicators showed a regular pattern in the control area. The results showed that among the Sample plot indicators the Morissita and Morissita standardized indicators expressed a clumped pattern in the recreational and the control area, and the Green indicator showed a regular pattern in the recreational area and the control area. The values obtained from the distance indicators showed that the degradation in the recreational area caused a change in the spatial pattern and the spatial pattern in the recreational area was changing so that most indicators in this area showed a regular pattern. Among the distance indicators used, C and Hines indicators and among the sample method, the Green indicator showed these differences well and the species of the two regions were identified suitable to describe the spatial pattern. Manuscript profile
    • Open Access Article

      4 - Investigation of Loss of Extracted Wood, Biomass and Carbon Storage of Commercial Trunk of Hornbeam and Date-plum Species in Astara Forests
      Seyede Nasrin  Ghaznavi
      In current study, in order to accurately estimate of the volume, loss of extracted wood, biomass, carbon sequestration and extraction of allometric equations of hornbeam and date-plum species, 17 trees from each of the mentioned species in parcel 729 of the series seven More
      In current study, in order to accurately estimate of the volume, loss of extracted wood, biomass, carbon sequestration and extraction of allometric equations of hornbeam and date-plum species, 17 trees from each of the mentioned species in parcel 729 of the series seven of the watershed number one of Astara forests were selected and after measuring the diameter and height their volume measured, using volume equation. The selected trees were then fallen and the volume of trees measured again. Finally, after converting trees trunk into smaller portable parts by mules, the volume of extracted wood was measured again and statistically compared with analysis of variance. Also, after weighing the fresh weight of the total parts, 4 cm disc samples were taken from the diameter in breast height of the trees and after weighing the initial weight and drying the samples in the oven at 80 ° C, the samples biomass were calculated. Carbon stock of the samples was measured by burning method in an electric kiln and the amounts of biomass and carbon sequestration were generalized to all trees. The allometric equations of the biomass of the two species were also extracted using the exponential function. Based on the results, the average loss of hornbeam and date-plum wood was estimated to be 42% and 32%, respectively. The total reserves of carbon and carbon dioxide deposited by the two species were estimated at 60 and 220 tons per hectare, respectively. In addition, the extracted allometric equations provided a high coefficient of explanation (>0.9) for both species. The results of the present study show the high loss of extracted wood and the high accuracy of the extracted allometric equations in estimating the biomass of the studied species. Manuscript profile
    • Open Access Article

      5 - Evaluation of forest road characteristics and comparison with environmental and technical standards (Case study: Tang-e-Sulk Bahmii Protected Area, South Zagros)
      Seyed Ata ollah Hosseini
      The aim of the study is to compare road geometric characteristics with standard road construction values. The study area is Tang-e-Sulak, protected area located in Bahmiy (Kohgiluyeh and Boyerahmad), at the southern Zagros forests. First, the existing road location was More
      The aim of the study is to compare road geometric characteristics with standard road construction values. The study area is Tang-e-Sulak, protected area located in Bahmiy (Kohgiluyeh and Boyerahmad), at the southern Zagros forests. First, the existing road location was taken using GPS and then placed on a topographic map. In the next step, the slopes were graded (from 0-10, 10-20, 20-30, 30-40, 40-50, 50-60 and > 60 percent), then 11 samples were randomly selected on each slope. In the next step, the size of the samples was compared with the standard values (Booklet No. 131 and 161). The width of the running surface and path of the way were analyzed on the basis of analytical and other road geometric characteristics based on descriptive statistics. Soil samples were taken from each of the slopes’ grades. Data analysis was done by T-test and Pearson correlation in SPSS 22. The results show that the width of the road and the construction area of the road on the slopes 10-20, 40-50, 60-50, and 60 were less than the standard values and it is statistically significance (P<0.01), and in other slopes wasn’t significant differences. Analytical descriptive statistics showed that the average slope of excavation and embankment walls is 15% higher than the standard value. The results of soil texture analysis by unified classification method showed silty- clay texture.Analytical descriptive statistics showed that the average slope of excavation and embankment walls is 15% higher than the standard value.The results of soil texture showed siltyclay texture. Manuscript profile
    • Open Access Article

      6 - Investigation of Diameter and Height Growth of Willow and Alder in Road Fill-Slope Landslide Bioengineering Stabilization (Surdar-Watashan District Chamestan, Mazandaran)
      Seyed Ata ollah Hosseini
      The aim of this study was to evaluate the diameter and height growth of two native species of alder (Alnus glutinosa L. Gaertn.) and willow (Salix alba L.) planted in three treatments including natural mulches of straw, wood chips and bare soil without mulch (as control More
      The aim of this study was to evaluate the diameter and height growth of two native species of alder (Alnus glutinosa L. Gaertn.) and willow (Salix alba L.) planted in three treatments including natural mulches of straw, wood chips and bare soil without mulch (as control) treatments. The design of the experiments was in the form of split plots and in the form of completely random blocks located in Chamestan, Mazandaran. The results showed that the regression relationships between diameter and height in alder species were better than those of willow species completely randomly. The study area was in parcels 5 of series 3 district of Surdar -Watashan forestry plan in watershed 49 of forests in the north of the country. The regression coefficient for the independent variable of diameter and dependent variable of height was 0.65 in alder and 0.42 in willow. The results showed that the regression relationship between diameter and height in alder was better than willow species. According to the results of variance analysis, the blocks and treatments did not have a statistically significant difference. The wood chips treatment created the best situation, and after that, the straw treatment and finally the control treatment (bare soil) had a more unfavorable situation than the other treatments. Finally, alder had more favorable conditions for adaptation to the applied bioengineering conditions of the present study vs. willow. Manuscript profile
    • Open Access Article

      7 - Study on flora, life form and chorotype of Kandoleh, Kermanshah province
      Rasoul Bagherabadi
      The study of the flora is important in management and development of natural resources because it shows the plant species presence and vegetation cover condition. The aim of this research was to identify the plant species, introducing the flora, determination of life fo More
      The study of the flora is important in management and development of natural resources because it shows the plant species presence and vegetation cover condition. The aim of this research was to identify the plant species, introducing the flora, determination of life forms, and plant geographical distribution of Kandoleh, in Kermanshah province. During vegetation growth, from 2020 we collected and identified plant species in the study region, and floristic list was provided. The results showed the collected species belong to 78 genera and 21 species in the region. The most important families were, Graminae (15.51%), Compositae (13.79%) and Leguminosae (10.3%) and Campanulaceae (9.48%) and Labiatae (8.6%). Life forms of plant species included hemicritophytosis 41.3%, tetrophytes 33.6%, chamaephytes 11.2%, Geophytes 8.6% and phanerophytes 5.1%. The high percentage of hemicritopathitis species indicated that the area has cold climate. The plants geographical distribution is related to Irano-touranian(75.57%), European- Mediterranean (15.51%), Irano-touranian/ Europe–Siberean (7.75%), cosmopolitan (3/34%), plural (3/4%), touranian (3.34%), Europe – Siberean (2.58%), Irano-touranian/ Mediterranean/ Europe – Siberean/ (1.72%), Irano-touranian/ Sahara-Sindian (0.86) Sahara-Sindian (0.86). Manuscript profile
    • Open Access Article

      8 - Effects of Fire on Vegetation in the shanderman Forests
      Nasrin Hajatpour shekari Hassan Pourbabaei Mehrdad Ghodskhah Daryaei Hamed Asadi
      This study was conducted with the aim of investigating the effects of fire on the vegetation in Shanderman forests (Guilan province). For this purpose, 60 sampling plots of 400 m2 were taken in a random-systematic Method in the areas of burned and control. The plant sp More
      This study was conducted with the aim of investigating the effects of fire on the vegetation in Shanderman forests (Guilan province). For this purpose, 60 sampling plots of 400 m2 were taken in a random-systematic Method in the areas of burned and control. The plant species present at the level of the samples were collected and identified, and their Life forms determined based on the Runkaeir's method. The results showed that 60 plant species were identified in the studied forest, 13 species (22%) only in the fire area, 5 species (8%) only in the control area, and 42 species (70%) were observed common in the both regions. The highest frequency belonged to Rosaceae and Poaceae families. In the study of the life forms of plant elements in the burned and control area, phanerophytes and hemicryptophytes were the most present in both regions. The results of the investigation of plant biodiversity indicators showed that the values of species diversity indicators in the burned area were higher than in the control area. DCA analysis showed that the composition of the vegetation in the burned area is not significantly different from the control area. Therefore, it can be concluded that after 12 years of the fire, the vegetation composition of the area has been restored and has become the same as the control area. Manuscript profile
    • Open Access Article

      9 - Investigating the effect of soil conditioners on the germination rate and percentage of Fraxinus excelsior seeds
      Hamed Asadi salime rahimnezhad Seyed Mohammad Hojjati Hameid jalilvand Mojtaba Mahmoudi
      Different fertilizers such as green, animal, chemical, biological and biochar are used in different nurseries to improve germination and growth. The purpose of this research is to investigate the effect of soil conditioners on the germination rate and percentage of Frax More
      Different fertilizers such as green, animal, chemical, biological and biochar are used in different nurseries to improve germination and growth. The purpose of this research is to investigate the effect of soil conditioners on the germination rate and percentage of Fraxinus excelsior seeds in forest nurseries. This experiment was carried out in Nursery Lajim, located in Sarjangalbani Kaslian, General Department of Natural Resources and Watershed of Swadkoh city. In this research, 20 soil conditioning treatments include rice husk to amount of 0.5% and 1% of soil volume, rice husk biochar to amount of 0.5%, 1% and 2% of soil volume, 150 and 300 grams of cow manure, minimum and maximum chemical fertilizer (minimum chemical fertilizer for super triple phosphate 0.6 grams, for ammonium sulfate 0.45 grams and potassium sulfate 0.45 grams and chemical fertilizer for triple superphosphate 1.2 grams, for ammonium sulfate 0.9 grams and potassium sulfate 0.9 grams) and the control treatment was considered with three repetitions. The seeds selected for the experiment were cultivated in the appropriate soil depth, by observing the first young seed on the 10th of April, counting of seeds has started. The quality of seed germination was leaf emergence. For statistical analysis, after checking the normality of the data and the homogeneity of variances using the Shapiro Wilk and Loon tests at the 95% probability level, one-way analysis of variance was used. If the data were significant, comparisons were made using Duncan's test. The results showed that the effect of soil conditioners on the speed and percentage of seed germination has a significant effect. The highest germination rate and percentage were observed in the treatments of 1.25% cow manure and 1% rice husk, 1% maximum chemical fertilizer and rice husk, 2% rice husk biochar and 1% rice husk biochar, and in general, the use of these materials had the greatest effect on seed Fraxinus excelsior. it is suggested to use organic materials such as rice husk and cow dung to increase the germination of Fraxinus excelsior seeds in forest nurseries. Manuscript profile