In order to evaluate the amount of poplar wood production in traditional poplar farming, an assessment of annual growth in different stands is necessary. In this study 8 Populus nigra stands along margins of different rivers of Kermanshah province were selected for the analysis. A number of 102 variable sample plots were measured by in a systematic random design. In each sample plot growth attributes were measured. The data was analyzed by one-way analysis of variance and Duncan test. In addition, soil samples were measured and the soil data were analyzed by correlation and PCA analysis. Results showed that the annual growth of 6th stand was three times higher than that of 4th stand, with their cumulated annual ranging between 10.3-38 m3. Furthermore, differences were observed in volume, height and diameter growth amongst the stands. Furthermore, differences were observed in volume, height and diameter growth amongst the stands.The conducted PCA analysis of soil samples showed a marginal significant difference amongst the samples, though no significant correlation between volume growth and soil characteristics was observed. For example decreasing EC and pH improved the volume growth, whereas increasing Clay, N and OC budget led to an increase in volume growth. Compared to the previously achieved results in the literature, the amount of poplar growth seems to be rather a function of management operations in farm rather than the genetic and edaphic attributes.

In order to plan and make managerial decisions for the development of wood farming in Guilan province, parameters such as area, distribution, and biometric variables of poplar trees were measured separately for each county. To conduct this research, the field of poplar plantations was located using the Global Positioning System (GPS) and measured with 100% inventory method. In each poplar plantation section, for every 2000 square meters, nine middle trees were measured for the biometric variables. The correlation between the characteristics of area and increment of trees with climatic indicators and soil was also plotted. According to the findings of this project, the total area of poplar plantations in Guilan province was 12,179 ha in 2018, with the highest belonging to Sowme`eh Sara county with 6,944 ha, comprising 11.8% of the county area. This county ranked first in poplar tree cultivation with the highest number and volume of trees. The area of poplar plantation was the lowest in Astara, Amlash, and Fouman counties. The highest mean age of trees was obtained in Rudbar and Tavalesh, while the lowest mean age and number of trees were obtained in Fouman county. The characteristics of the total number of trees, volume, and area of poplar plantation showed the highest correlation coefficient with climatic indicators and total nitrogen. The findings of this research can provide valuable basic information for monitoring the area of poplar plantations, planning and management decisions, and identifying areas suitable to poplar plantations for wood farming in Guilan province and the country.

Background and objectives: Globally, chainsaws are extensively used for motor-manual tree felling and processing, making them a significant part of wood harvesting. However, this can pose a threat to the sustainability of forest operations from an ergonomic perspective. Chainsaw usage in logging operations is recognized as strenuous work, exposing workers to safety risks and harmful factors. The MASHOUF PSI 9700, a new chainsaw model, has gained popularity in the wood harvesting sector. However, the extent of ergonomic effects during its operation remains unexplored. This study aims to evaluate the noise exposure levels during tree felling using this specific chainsaw model in a poplar plantation in the western part of Guilan province, Iran. Methodology: This study was conducted in Tanyan forest district number 2, located around Soumesara, Guilan province. The felling operation was performed using the MASHOUF PSI 9700 chainsaw in a poplar plantation. The forest worker involved had over 20 years of experience in poplar plantations. Field data collection spanned one working day, during which a total of 133 trees were felled. Sound level measurements during the tree felling operations were taken at 5-second intervals using a TESTO 815 sound meter, in accordance with the ISO 1996-1 standard. The sound was measured along the arm and at the height of the worker’s ear using the A-weighting filter with Fast time setting enabled, within the range of 80-130 dB. The sound levels recorded at each stage were averaged to obtain the average pressure level. Results: The majority of the time consumption was attributed to tree felling, accounting for 46.02% of the total production time. The highest average sound levels were observed during the undercut (102.01 dB(A)) and backcut (100.46 dB(A)) work elements. The sound levels during the work elements of walk to tree, quire for felling, chainsaw refueling, technical delays, operational delays, and personal delays were 69.43, 72.62, 69.32, 87.10, 78.19, and 67.20 dB(A), respectively. Additionally, an increase in the diameter of the trees also led to an increase in the felling duration and the forest worker’s exposure to noise. Upon comparing the normal data related to the leveled sound curve and the permitted exposure times to these sound intensities, it was observed that the equivalent sound levels and the duration of exposure, in most cases, were below the allowed limits. This was evident for undercut, backcut, and the overall felling duration. Conclusion: The results of this study indicate that the MASHOUF PSI 9700 chainsaw exposes cutting workers to high noise levels. To mitigate the adverse effects of exposure to chainsaw noise, it is necessary to equip workers with personal safety equipment such as ear protection, consider taking breaks between tasks, and ensure timely maintenance of chainsaws. Furthermore, organizing on-the-job training courses focused on ergonomic topics and subjecting chainsaw operators to regular health checks may be crucial for early identification and prevention of hearing loss.

The present project was implemented with the aim of identifying the characteristics of local poplar plantations in Markazi province and determining their area, growth and wood production during 2018-2019., 47 sample plots were selected by random sampling in 6 cities of the province and site characteristics and quantitative and qualitative variables of trees were measured and recorded. For the vegetative variables of trees, 30 trees in each plot were randomly measured and the data were analyzed based on nested design with city factors and poplar plantations within the city and for qualitative traits, their frequency percentage was calculated. 70. 21% of poplar plantations in Markazi province were black poplar (Populus nigra L. ) and 29. 79% were white poplar (P. alba L. ). About 63. 83% of trees had narrow pyramidal crown, very elongated and elongated, 65. 96% of trees had very right and right trunk shape, 82. 98% of trees planted through cutting, 72. 34% of trees irrigated by flooding, 61. 7% of the trees planted in a dense group (stand) and 74. 47% of the trees had the main structure (single trunk). The mean annual volume increment of poplar plantations in Markazi province was 29. 13 m3ha-1y-1and the mean annual volume increment range of the province was between 4. 6 to 74. 67 m3/ha due to stands different age and differences among vegetative state. The highest number of trees, plots and poplar plantations area was obtained for Shazand (38064 trees, 19 plots and 156959 m2) and Saveh region was in the second place in terms of these characteristics.

Background and objectives: Populus alba L. is the dominant poplar species grown in Chaharmahal and Bakhtiari Province, Iran, typically planted using traditional methods. These methods result in trees with small diameters and tall heights, which are unsuitable for use in large-scale wood industries. There is a lack of comprehensive information regarding species type, tree age, current growth, annual yield, and harvest volume in the poplar plantations of the province. The primary objective of this research was to monitor and evaluate both quantitative and qualitative data on the current status of poplar cultivation in Chaharmahal and Bakhtiari Province. Methodology: This study was conducted in Farsan and Kiyar counties, which contain the largest areas of poplar plantations in the province. A total of 39 sample plots, ranging in size from 2, 500 to 4, 900 m², were selected based on plantation density. In group plantings, 9 trees were sampled at the beginning, 9 in the middle, and 9 at the end of each plot. In strip cultivation, linear sampling was conducted in two directions, east-west and north-south, selecting at least 15 trees along each line. Quantitative and qualitative variables of standing trees were recorded, including species type, age, planting density, propagation method (cuttings or seedlings), production system type (group, stand, or strip planting), planting location (field edges or windbreaks), diameter at breast height, height, and volume growth. Economic and social factors, such as harvest age and felling time, were also examined. Management practices, including irrigation, soil enhancement, and pest and disease control, were documented. Data were analyzed using random sampling classification methods. Results: A comparison of tree age between group and strip planting methods showed that increasing tree diameter is limited in group plantings due to higher planting density. As a result, traditional group plantings lead to early harvesting of smaller-diameter trees. In contrast, strip planting allows for greater tree age and diameter, owing to wider spacing and lower density. In group plantings, with an average tree age of 8. 5 years, the mean diameter at breast height was 8. 3 cm, the average height was 12. 2 m, and the mean volume per tree was 0. 0427 m³. In strip plantings, the average tree age was 15. 5 years, with a diameter of 18. 86 cm, height of 16. 1 m, and volume per tree of 0. 227 m³. Three planting spacing types were identified across the province. The most common spacing was 1. 5×1 m², used in 64. 9% of plantations, while 1×0. 5 m² spacing accounted for only 8. 1%. The 1×1 m² spacing represented 27%. The highest and lowest planting densities were recorded in Farsan and Kiyar counties, with 6, 214 and 5, 275 trees per hectare, respectively. Conclusion: Maximum wood production in Chaharmahal and Bakhtiari Province can be achieved by integrating traditional knowledge with scientific cultivation methods. Based on the findings of this study, a poplar development program can be implemented, involving increased planting spacing to 2×2 m², soil enhancement according to soil analysis, regular pruning, and effective pest and disease management.  

The effects of some soil properties on growth of three-year poplars (Populus nigra L. ) were investigated in two poplar stands in south of Tehran. For this purpose, at the end of growth period, in each poplar stand, three sample plots (3×4 m) were chosen using technique of systematic random sampling. Diameter at breast height and height parameters of trees were measured and then basal area and volume computed. In order to study soil properties (texture, organic matter, pH, EC and NPK), in each plot, three soil samples were taken in depths of 15-30 and 30-60 cm. Results demonstrated that some soil properties (sand, silt and clay percent, K content and EC) of two poplar stands had significant differences, as a consequence growth parameters of two poplar stands also showed significant differences. So that, in stand 1 volume of three-year poplar tree was 3 times volume in stand 2. In general, loamy-clay soil with higher absorbable K (415/16 mg/kg) and lower EC (1/36 ds/m) (stand 1) provided better growth conditions for poplar trees compared with loamy-silty soil with medium absorbable K (219/43 mg/kg) and higher EC (4/43 ds/m) (stand 2). Also, positive correlation between growth parameters of poplar trees with sand and clay percent and K content and negative correlation with silt percent and EC were observed. The results of current study demonstrated that attention to soil properties before poplar plantation is necessary to achieve maximum wood production.

Introduction and Objective: Due to the scattering of poplar plantations in the city of Sowme`eh Sara, Gilan province and the lack of timely, documentary and scientific information from the current status, it is necessary to determine the exact location of the distribution, area and volume of its poplar plantations. In the present study, area, distribution and status of poplar plantation and biometric statistics of poplar trees in Sowme`eh Sara city and their wood production were measured separately for each village. Materials and Methods: First, through field operations, the field of poplar plantations with the Global Positioning System (GPS) and the use of GPS Fields Area Measure PRO application was located and uploaded to Google Earth and the poplar cultivation pattern was determined. After drawing the poplar plantation polygons on Google Earth, they were transferred to ArcGIS and converted to an integrated polygon layer in shp format. After the completion of the map each village, the field control was performed and the biometric information of each section was recorded, including the measuring diameter at breast height and height of trees and then their volume was calculated, and then the distribution map and the total location of the existing poplar plantations in the city were prepared. Also, climate maps of temperature and precipitation this city were drawn by receiving data from three meteorological stations related to the ten-year period (2008-2017) and some soil characteristics of Sowme`eh Sara city were prepared separately for each village related to 0-30 cm depth with 138 harvest points. Results: The results showed that the total area of poplar plantations in Sowme`eh Sara city is 6, 944 ha and Ziaber village with 29. 65% is the first grade in the percentage of land allocation to poplar plantation with maximum area of poplar plantation section and the highest number and volume of trees. There are a number of 99 poplar plantations fields with an area of less than 500 m2 and 1584 poplar plantations fields with an area of more than 1 ha, which include 3. 22 ha and 5471 ha of poplar plantations areas in this city, respectively. The wood obtained from about 91% of the total area of poplar plantation in the city is dedicated to concentrated cultivation and industrial uses. The highest average diameter at breast height and height of trees in Tolmat village and the lowest of them in Hendukhaleh village were obtained. The results of soil properties showed that the soil texture of the studied villages was mainly loamy-clay texture that is suitable for poplar cultivation and development, but the pH of the soil showed different values in each village. Conclusion: Considering the total volume of trees in Sowme`eh Sara city with the amount of 3411884 m3, this amount of wood volume can provide about a quarter of the country's annual wood consumption.

Introduction and Objective: Density is a determinant and key factor in the development of a forest stand. In dense stands, competition is high, development occurred late due to limited access to resources, and are highly vulnerable to natural events such as insect infestation, fire, and drought. In contrast, low-density stands will not use the resources available in the habitat efficiently and the return of invested capital will decrease. Therefore, optimal density in forest stands is effective in the optimal use of resources in the habitat and maintaining health and growth in a stand. The present study was conducted to determine the optimal density in the afforestation stands of Populus deltoides in Guilan province and by selecting four pure stands of this species at different ages that had good distribution in the province. Material and Methods: The characteristics of the density (number per hectare of all trees) were counted and the diameter at breast height and the total height of trees were measured within one hectare (100 × 100 meters) area sampling plots. Stand Density Index (SDI) was calculated in order to evaluate the optimal amount of density based on allometric equations. Results: The results indicated that the existing density in Langrood (22 years of age with 5×5 m planting distance), Siahkal (29 years of age with 3×5 m planting distance), Shaft (38 years of age with 3×3 m planting distance), and Talesh (37 years of age and 5×3. 5 m planting distance) regions were 129, 216, 325, and 190, respectively,and the optimal density was 188, 259, 379, and 337 respectively in these areas. The results indicated that the existing density in Langrood, Siahkal, Shaft, and Talesh regions were 129, 216, 325, and 190, respectively,and the optimal density was 188, 259, 379 and 337 respectively,and having no significant difference (except in Talesh area) with existing density in these areas (p<0. 05). The existing density and the optimal density diagrams relative to the diameter classes showed that the diameter classes have a good density in lower classes, the two diagrams were very close to each other and there was overlap in the low classes. The 25 cm diameter class was observed as an intersection between the two diagrams. But, there was a greater difference between the optimal density and the existing density in the higher diameter classes. Conclusion: The results of this study will be a suitable guide for easy and fast comparison between the existing and ideal density according to the species growing condition in the habitat, evaluation, and decision-making of appropriate management of trees density in afforestation.

Poplar is very important as a fast-growing species in the country's industry. So far, popular information such as level ٬ volume and harvest has been obtained using unscientific and weak methods. Due to the lack of comprehensive, up-to-date, and reliable information in the country about poplars, the study of identifying potential and actual facilities of poplar cultivation from different aspects such as area, volume, harvest, distribution, and species in four provinces (East Azerbaijan, Zanjan, Ardabil and Kermanshah) which have a great potential for poplar plantation was done. The cluster sampling method was used in two steps. The first stage was the collection of library information and semi-open interviews in the rural areas and the second stage was the field survey in the villages of these four provinces. The data obtained from the field survey were items such as poplar cultivation area, poplar stand volume, dominant species in each region, and volume estimation through volume and weight tables. The results show that the average annual harvest volume in the four studied provinces is 43156 cubic meters with the average error obtained based on the comparison between the two methods of interview and field method is 15%. The area of poplar in the four above-mentioned provinces (18039 hectares) is about 10% of the total area of poplar in the country, which shows an 8% decrease in poplar in these four provinces compared with previous years.