Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Assessing Forest Structure and Biodiversity in Community Forests and the Spatial Distribution of Local Disturbances Assessing Forest Structure and Biodiversity in Community Forests and the Spatial Distribution of Local Disturbances 511 530 212576 10.22034/ijf.2024.413621.1942 FA Sewak Bhatta Student,, Dept. of Wood and Forest Science, Université Laval, Québec, Canada. Rajeev Joshi Assistant Prof., College of Natural Resource Management, Faculty of Forestry, Agriculture and Forestry University, Katari-56310, Udayapur, Nepal. Santosh Ghimire Student, Faculty of Forestry, Agriculture and Forestry University, Hetauda-44107, Nepal. Journal Article 2023 08 27 Understanding forest structure, biodiversity, and local disturbance patterns is critical for effective community forest management, yet such integrated assessments remain limited. This study evaluates forest structure, plant biodiversity, and the spatial distribution of local disturbances in three community forests (Banelpokhari, Okhardhara, and Suntalidada) located in Godawari Municipality, Nepal. Using a systematic random sampling design, 90 circular plots were established to measure trees (500 m²), poles (100 m²), saplings (25 m²), and seedlings (10 m²). Biodiversity indices (Shannon–Wiener, evenness, richness, Importance Value Index) were computed, and Sentinel-2A imagery (2017 and 2022) was analyzed using NDVI to assess land cover changes. Results show that Pinus roxburghii was the dominant species across all forests, with the highest IVI (281.25) in Okhardhara CF. Suntalidada CF exhibited the greatest Shannon–Wiener diversity (H' = 3.52), evenness (0.96), and species richness (25). Forest structure revealed the highest stem density in the 0–10 cm diameter and 0–5 m height classes, and the lowest in >40 cm and >20.1 m classes. Key disturbances included road development, encroachment, soil erosion, and illegal logging. From 2017 to 2022, dense forest cover decreased by 9% (Banelpokhari), 19% (Okhardhara), and 11% (Suntalidada), with concurrent increases in sparse vegetation and infrastructure. These findings underscore the need for targeted conservation interventions, adaptive management, and collaborative approaches to mitigate anthropogenic pressures and sustain biodiversity in community-managed forests. Understanding forest structure, biodiversity, and local disturbance patterns is critical for effective community forest management, yet such integrated assessments remain limited. This study evaluates forest structure, plant biodiversity, and the spatial distribution of local disturbances in three community forests (Banelpokhari, Okhardhara, and Suntalidada) located in Godawari Municipality, Nepal. Using a systematic random sampling design, 90 circular plots were established to measure trees (500 m²), poles (100 m²), saplings (25 m²), and seedlings (10 m²). Biodiversity indices (Shannon–Wiener, evenness, richness, Importance Value Index) were computed, and Sentinel-2A imagery (2017 and 2022) was analyzed using NDVI to assess land cover changes. Results show that Pinus roxburghii was the dominant species across all forests, with the highest IVI (281.25) in Okhardhara CF. Suntalidada CF exhibited the greatest Shannon–Wiener diversity (H' = 3.52), evenness (0.96), and species richness (25). Forest structure revealed the highest stem density in the 0–10 cm diameter and 0–5 m height classes, and the lowest in >40 cm and >20.1 m classes. Key disturbances included road development, encroachment, soil erosion, and illegal logging. From 2017 to 2022, dense forest cover decreased by 9% (Banelpokhari), 19% (Okhardhara), and 11% (Suntalidada), with concurrent increases in sparse vegetation and infrastructure. These findings underscore the need for targeted conservation interventions, adaptive management, and collaborative approaches to mitigate anthropogenic pressures and sustain biodiversity in community-managed forests.

https://www.ijf-isaforestry.ir/article_212576_3c9fac38445503307b83e0e47e9149ce.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Timber Smuggling Criminology and Environmental Justice: The Perspective of Forest Guards in the Southern Forests of Guilan Timber Smuggling Criminology and Environmental Justice: The Perspective of Forest Guards in the Southern Forests of Guilan 531 547 231273 10.22034/ijf.2025.501658.2034 FA HamidReza Afrand Ph.D. of Forest Law & Policy, Natural Resources and Watershed Management Organization, Tehran, I.R.Iran 0009-0001-6846-160X Ramin Naghdi Prof., Dept. of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, I. R. Iran 0000-0002-6671-0369 Fariborz Daliri M.Sc. Student., Dept. of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, I. R. Iran Iman Khosravi Ph.D. student of Agricultural Extension & Education, University of Tehran, Karaj, I.R.Iran Journal Article 2025 01 25 The importance of the Hyrcanian forests, along with the growing wave of environmental concerns about their protection, as well as certain political orientations, led to the Iran’s Sixth Development Plan law banning any timber utilization of forest trees. This ban, which became known as the Forest Breathing Plan, has been viewed by many forest experts as a disregard for the multiple functions of forests, a weakening of Principle 45 of the Constitution, destruction of national wealth and Anfal, layoffs of workers, forest rangers, and chainsaw technicians, leaving them in the abyss of inaction and unemployment, and sometimes creating or strengthening a sense of revenge against the forests and the Natural Resources and Watershed Organization, manifesting in aiding, accessary or stewardship in the crime of timber smuggling. In contrast, the main arguments of those in favor of the Breathing Plan focused on banning forest harvesting, citing the need to protect the Hyrcanian forests as a biosphere reserve, avoiding encroachment on forests by relying on supplying the required wood through imports and tree plantations, allocating budget for forest protection by Parliament, and similar matters. Either way the cessation of wood harvesting from forest trees has led to a shortage of wood production, increased demand from the wood industry, and rising prices. As a result of local poverty and the greed of some smugglers, the forests have become vulnerable to timber smuggling. This situation undermines the establishment of environmental justice between those who commit smuggling for subsistence purposes compared to professional smugglers. The present study attempts to examine the perspectives of forest guards of the Rostam-Abad Natural Resources Unit in dealing with timber smuggling, using open and semi-structured focus group interview techniques. The interview was recorded and transcribed in Word software and analyzed with NVivo software. From the perspective of the Forest Security Unit, the most important reason for resorting to smuggling is the high profits from selling smuggled timber. Also, the lack of organizational transportation vehicles and the lack of legal protection against smugglers are among the most important challenges for the guards. In their opinion, spreading a culture of respect to environment, seeking help from local people, making a sense of belonging to the forest in forest dwellers, and being aware of the heavy fines for timber smuggling are the most important social and cultural solutions to combat this crime. Additionally, the main policy to combat timber smuggling is stated to be inter-sectoral cooperation between organizations. According to interviewees, the performance of the Natural Resources Organization in combating timber smuggling is considered successful and acceptable, especially after the increase in the number of security companies since 2018. Finally, the research concludes that revising the implementation of the Breathing Plan and the cessation of forest timber utilization, amending laws related to tree felling and formulation of new and positive policies to combat timber smuggling, are among the most important solutions in the southern forests of Guilan province. The importance of the Hyrcanian forests, along with the growing wave of environmental concerns about their protection, as well as certain political orientations, led to the Iran’s Sixth Development Plan law banning any timber utilization of forest trees. This ban, which became known as the Forest Breathing Plan, has been viewed by many forest experts as a disregard for the multiple functions of forests, a weakening of Principle 45 of the Constitution, destruction of national wealth and Anfal, layoffs of workers, forest rangers, and chainsaw technicians, leaving them in the abyss of inaction and unemployment, and sometimes creating or strengthening a sense of revenge against the forests and the Natural Resources and Watershed Organization, manifesting in aiding, accessary or stewardship in the crime of timber smuggling. In contrast, the main arguments of those in favor of the Breathing Plan focused on banning forest harvesting, citing the need to protect the Hyrcanian forests as a biosphere reserve, avoiding encroachment on forests by relying on supplying the required wood through imports and tree plantations, allocating budget for forest protection by Parliament, and similar matters. Either way the cessation of wood harvesting from forest trees has led to a shortage of wood production, increased demand from the wood industry, and rising prices. As a result of local poverty and the greed of some smugglers, the forests have become vulnerable to timber smuggling. This situation undermines the establishment of environmental justice between those who commit smuggling for subsistence purposes compared to professional smugglers. The present study attempts to examine the perspectives of forest guards of the Rostam-Abad Natural Resources Unit in dealing with timber smuggling, using open and semi-structured focus group interview techniques. The interview was recorded and transcribed in Word software and analyzed with NVivo software. From the perspective of the Forest Security Unit, the most important reason for resorting to smuggling is the high profits from selling smuggled timber. Also, the lack of organizational transportation vehicles and the lack of legal protection against smugglers are among the most important challenges for the guards. In their opinion, spreading a culture of respect to environment, seeking help from local people, making a sense of belonging to the forest in forest dwellers, and being aware of the heavy fines for timber smuggling are the most important social and cultural solutions to combat this crime. Additionally, the main policy to combat timber smuggling is stated to be inter-sectoral cooperation between organizations. According to interviewees, the performance of the Natural Resources Organization in combating timber smuggling is considered successful and acceptable, especially after the increase in the number of security companies since 2018. Finally, the research concludes that revising the implementation of the Breathing Plan and the cessation of forest timber utilization, amending laws related to tree felling and formulation of new and positive policies to combat timber smuggling, are among the most important solutions in the southern forests of Guilan province.

https://www.ijf-isaforestry.ir/article_231273_4369596fa19924f663ad29c25de2364e.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Evaluation of the Lack of Implementation of Maintenance Operations on Forest Road Pavements Evaluation of the Lack of Implementation of Maintenance Operations on Forest Road Pavements 549 558 243803 10.22034/ijf.2025.472555.2004 FA Yaser Zare Ph.D. Student in Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. Ramin Naghdi Prof., Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. 0000-0002-6671-0369 Ismael Ghajar Assistant Prof., Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. Journal Article 2024 08 22 The cost of maintaining forest roads is an important factor in forest management and is related to pavement deterioration and the identification of factors affecting the pavement. The aim of this study was to evaluate the deterioration of forest road pavements over a four-year period in watershed 25 of Shenroud in Guilan Province. For this purpose, 213 sample plots were selected through systematic random sampling and measured. In each sample plot, the pavement deterioration index was measured based on seven indicators: deteriorated cross-section, deteriorated drainage, dust production, corrugation, potholes, ruts, and soil mass loss. Friedman test, analysis of variance, and Duncan’s test were used to analyze the data. The results showed that over time, deterioration caused by cross-section, roadside drainage, dust production, corrugation, and soil mass loss increased, and there was a statistically significant difference between the beginning and the end of the study period. The mean depth (from 4.57 to 4.77 cm), area (from 4.44 to 4.50 cm²), and number of potholes (from 1.23 to 2.20), as well as the mean depth (from 1.95 to 2.00 cm), area (from 1.22 to 1.24 cm²), and number of ruts (from 0.43 to 0.45), showed an increasing trend. The statistical results showed that there was a significant difference between the number of potholes in different years, while there was no significant difference among pothole area and depth or rut area, depth, and number across the different study periods. The results of Duncan’s mean comparison test also showed that there was a significant difference between the average number of potholes created at the end of the study period (2023) and at the beginning of the period (2020). In general, the results of this study show the importance of carrying out continuous maintenance operations and the need to use evaluation indicators in planning forest road pavement maintenance. The cost of maintaining forest roads is an important factor in forest management and is related to pavement deterioration and the identification of factors affecting the pavement. The aim of this study was to evaluate the deterioration of forest road pavements over a four-year period in watershed 25 of Shenroud in Guilan Province. For this purpose, 213 sample plots were selected through systematic random sampling and measured. In each sample plot, the pavement deterioration index was measured based on seven indicators: deteriorated cross-section, deteriorated drainage, dust production, corrugation, potholes, ruts, and soil mass loss. Friedman test, analysis of variance, and Duncan’s test were used to analyze the data. The results showed that over time, deterioration caused by cross-section, roadside drainage, dust production, corrugation, and soil mass loss increased, and there was a statistically significant difference between the beginning and the end of the study period. The mean depth (from 4.57 to 4.77 cm), area (from 4.44 to 4.50 cm²), and number of potholes (from 1.23 to 2.20), as well as the mean depth (from 1.95 to 2.00 cm), area (from 1.22 to 1.24 cm²), and number of ruts (from 0.43 to 0.45), showed an increasing trend. The statistical results showed that there was a significant difference between the number of potholes in different years, while there was no significant difference among pothole area and depth or rut area, depth, and number across the different study periods. The results of Duncan’s mean comparison test also showed that there was a significant difference between the average number of potholes created at the end of the study period (2023) and at the beginning of the period (2020). In general, the results of this study show the importance of carrying out continuous maintenance operations and the need to use evaluation indicators in planning forest road pavement maintenance.

https://www.ijf-isaforestry.ir/article_243803_365a597a7850e5e042d68d80f9cf8646.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Evaluating Timber Volume Discrepancies in Teak Plantations of the Sagarnath Forest Development Project, Nepal: A Comparative Study Evaluating Timber Volume Discrepancies in Teak Plantations of the Sagarnath Forest Development Project, Nepal: A Comparative Study 559 569 231425 10.22034/ijf.2025.492785.2023 FA Anish Baral Tribhuvan University, Institute of Forestry, Pokhara Campus, Pokhara. Rajeev Joshi College of Natural Resource Management, Faculty of Forestry, Agriculture and Forestry University, Katari-56310, Udayapur, Nepal. Santosh Ghimire Faculty of Forestry, Agriculture and Forestry University, Hetauda-44107, Nepal. Aman Prabhakar College of Natural Resource Management, Faculty of Forestry, Agriculture and Forestry University, Katari-56310, Udayapur, Nepal. Pramod Subedi Faculty of Forestry, Agriculture and Forestry University, Hetauda-44107, Nepal. 0009-0004-0608-8346 Journal Article 2024 12 07 Accurate forest biomass estimation, productivity, yield regulation, and carbon stock rely on precise volume prediction at both the individual tree and stand levels. This study, titled “Comparison of Standing and After-Felled Volume of Timber in Teak Plantation in the Sagarnath Forest Development Project, Nepal,” was conducted in the Sagarnath Forest Development Project (SFDP) in Sarlahi District. The primary objective of this research was to calculate the disparity in timber volume before and after harvesting in a teak forest. The 2D felling site provided 150 sample trees for data collection. Before felling, the diameter at breast height (DBH) of standing trees was measured using a diameter tape, tree height was measured with a range finder, and tree quality class was determined based on community forest inventory guidelines. After felling, the total length of the log, girth at the mid-length of the log, and the length and diameter of hollowness and the depth of the buttress were measured using a measuring tape. To compute timber volume before felling, the formula defined in the Community Forest Resource Inventory Guideline, 2061 was utilized, while the quarter-girth formula was employed to calculate timber volume after felling. The findings indicated an overestimation of 696.80 cubic feet of timber before harvesting. A 95% confidence interval F-test demonstrated a significant difference in timber volume before and after felling. There was a loss of 14.58 cu. ft of timber volume due to hollowness in the tree, and 83.10 cu. ft of timber was lost due to buttresses. Likewise, a difference in volume was observed based on quality class due to inaccurate classification. Accurate forest biomass estimation, productivity, yield regulation, and carbon stock rely on precise volume prediction at both the individual tree and stand levels. This study, titled “Comparison of Standing and After-Felled Volume of Timber in Teak Plantation in the Sagarnath Forest Development Project, Nepal,” was conducted in the Sagarnath Forest Development Project (SFDP) in Sarlahi District. The primary objective of this research was to calculate the disparity in timber volume before and after harvesting in a teak forest. The 2D felling site provided 150 sample trees for data collection. Before felling, the diameter at breast height (DBH) of standing trees was measured using a diameter tape, tree height was measured with a range finder, and tree quality class was determined based on community forest inventory guidelines. After felling, the total length of the log, girth at the mid-length of the log, and the length and diameter of hollowness and the depth of the buttress were measured using a measuring tape. To compute timber volume before felling, the formula defined in the Community Forest Resource Inventory Guideline, 2061 was utilized, while the quarter-girth formula was employed to calculate timber volume after felling. The findings indicated an overestimation of 696.80 cubic feet of timber before harvesting. A 95% confidence interval F-test demonstrated a significant difference in timber volume before and after felling. There was a loss of 14.58 cu. ft of timber volume due to hollowness in the tree, and 83.10 cu. ft of timber was lost due to buttresses. Likewise, a difference in volume was observed based on quality class due to inaccurate classification.

https://www.ijf-isaforestry.ir/article_231425_9baa786212825523d38541fcfeb8e813.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Genetic diversity in Quercus petraea Liebl. of North West of Iran based on SCoT markers Genetic diversity in Quercus petraea Liebl. of North West of Iran based on SCoT markers 571 580 243806 10.22034/ijf.2025.490673.2020 FA Yousef Mohammadi Assistant Prof., Research institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran. 0000-0001-5231-1546 Shiva Gheytaranpour -Sehrigh Ph.D. Faculty of Agriculture, University of Tabriz, Tabriz, Iran. Sajad Ghanbari Prof., Ahar Faculty of Agriculture and Natural Resources, University of Tabriz, Tabriz, Iran. 0000-0002-6568-1025 Journal Article 2024 12 07 The Arasbaran forest is one of the genetic hotspots of the biosphere due to its high species diversity, and the white oak species plays a special role in the composition and diversity of the biological elements of Arasbaran forests. In this regard, it is necessary and important to evaluate the genetic diversity of the identified seed production area of white oak. In this research, the genetic diversity within and between seven different white oak populations, including 49 different trees, was investigated using the SCoT molecular marker. A total of 129 alleles were observed for these markers, and 100% of the produced alleles were polymorphic. The number of alleles varied from 16 to 29, with marker SCoT41 having the highest number at 29 alleles and marker SCoT7 having the lowest number at 16 alleles. Analysis of molecular variance (AMOVA) showed that 90% of the observed genetic diversity was distributed within populations, while 10% occurred among populations, suggesting that genetic variability within populations was more significant than that among populations. Based on the UPGMA dendrogram, individuals were partitioned into six distinct clades, and according to the UPGMA and PCA patterns, geographical proximity has not played an important role in the formation of the genetic structure of these populations. This research has provided initial insight into the genetic diversity within and between different populations of the Arasbaran white oak species. As a result, it is suggested that, by studying other markers, useful information for conservation and management measures for this valuable species can be obtained. The Arasbaran forest is one of the genetic hotspots of the biosphere due to its high species diversity, and the white oak species plays a special role in the composition and diversity of the biological elements of Arasbaran forests. In this regard, it is necessary and important to evaluate the genetic diversity of the identified seed production area of white oak. In this research, the genetic diversity within and between seven different white oak populations, including 49 different trees, was investigated using the SCoT molecular marker. A total of 129 alleles were observed for these markers, and 100% of the produced alleles were polymorphic. The number of alleles varied from 16 to 29, with marker SCoT41 having the highest number at 29 alleles and marker SCoT7 having the lowest number at 16 alleles. Analysis of molecular variance (AMOVA) showed that 90% of the observed genetic diversity was distributed within populations, while 10% occurred among populations, suggesting that genetic variability within populations was more significant than that among populations. Based on the UPGMA dendrogram, individuals were partitioned into six distinct clades, and according to the UPGMA and PCA patterns, geographical proximity has not played an important role in the formation of the genetic structure of these populations. This research has provided initial insight into the genetic diversity within and between different populations of the Arasbaran white oak species. As a result, it is suggested that, by studying other markers, useful information for conservation and management measures for this valuable species can be obtained.

https://www.ijf-isaforestry.ir/article_243806_87ec1bbb4e0533c348ad45224564c86f.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 GIS-Based Evaluation of Fire Station Accessibility in Zawita, Duhok GIS-Based Evaluation of Fire Station Accessibility in Zawita, Duhok 581 596 243808 10.22034/ijf.2026.543401.2065 FA Aree Abdulkhaleq Abdulqader Ph.D. student of Forest Sciences, Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Iraq 0009-0002-1872-2020 Abdulkhalik AL Taei Prof., Dept. of Civil Engineering, College of Engineer, University of Mosul, Iraq 0000-0002-6413-1478 Mohammedamin Yassin Taha Assistant Prof., Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Iraq 0000-0002-6828-0665 Journal Article 2025 08 26 Wildfires present a major threat to the ecologically valuable forests of the Zawita District in northern Iraq, where anthropogenic activities (human-caused) and limited firefighting capability create additional threats. While there is an actual fire station (F1) in the district, its coverage is limited. Thus, this study sought to test whether the addition of a new fire station (F2) in the center of the district would improve suppression efficiency. Using GIS-based network analysis software (ArcGIS 10.8), we modeled road accessibility and travel time to 33 forest zones based on assumptions regarding asphalt and forest road conditions. Travel times for firefighting trucks were calculated for both F1 and F2 conditions under a critical response time of 15–20 min. We developed a third-degree polynomial regression model and validated the relationship between response time and burnt area, with excellent fit (R² = 0.9999 calibration; R² = 0.9984 validation). Predicting burnt areas for both F1 and F2 scenarios for all forest zones enabled quantifying their relative effectiveness. F1 covered 72% (305 km²) of the study area over the 20-minute time frame, while F2 covered 70% (293 km²). While F1 had one more zone in the critical time frame compared to F2 (27 vs. 26), our regression model shows that F2 produced quicker responses in the key central zones, which led to a net reduction of 288000 m2 of burnt area in the district. The polynomial model demonstrated that brief delays in response time had an exponential effect on fire damage, emphasizing the need for better and strategically placed stations. The suggested model incorporates both stations (F1 + F2) to achieve the best trade-off in overall geography and improved accessibility from a central location. This recommendation corresponds to increased capacity for wildfire suppression, less loss of forests, and serves as a precedent for disaster planning in similar ecologically sensitive, resource-poor areas. Wildfires present a major threat to the ecologically valuable forests of the Zawita District in northern Iraq, where anthropogenic activities (human-caused) and limited firefighting capability create additional threats. While there is an actual fire station (F1) in the district, its coverage is limited. Thus, this study sought to test whether the addition of a new fire station (F2) in the center of the district would improve suppression efficiency. Using GIS-based network analysis software (ArcGIS 10.8), we modeled road accessibility and travel time to 33 forest zones based on assumptions regarding asphalt and forest road conditions. Travel times for firefighting trucks were calculated for both F1 and F2 conditions under a critical response time of 15–20 min. We developed a third-degree polynomial regression model and validated the relationship between response time and burnt area, with excellent fit (R² = 0.9999 calibration; R² = 0.9984 validation). Predicting burnt areas for both F1 and F2 scenarios for all forest zones enabled quantifying their relative effectiveness. F1 covered 72% (305 km²) of the study area over the 20-minute time frame, while F2 covered 70% (293 km²). While F1 had one more zone in the critical time frame compared to F2 (27 vs. 26), our regression model shows that F2 produced quicker responses in the key central zones, which led to a net reduction of 288000 m2 of burnt area in the district. The polynomial model demonstrated that brief delays in response time had an exponential effect on fire damage, emphasizing the need for better and strategically placed stations. The suggested model incorporates both stations (F1 + F2) to achieve the best trade-off in overall geography and improved accessibility from a central location. This recommendation corresponds to increased capacity for wildfire suppression, less loss of forests, and serves as a precedent for disaster planning in similar ecologically sensitive, resource-poor areas.

https://www.ijf-isaforestry.ir/article_243808_05f57dfbcb8a28ddea924dcb1080c7ed.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Allometric Equations for Leaf Carbon Sequestration and Leaf Area Index in Anagyris foetida L.: Implications for Conservation in Zagros Forests Allometric Equations for Leaf Carbon Sequestration and Leaf Area Index in Anagyris foetida L.: Implications for Conservation in Zagros Forests 597 610 243810 10.22034/ijf.2026.547702.2072 FA Ali Mahdavi Prof., Dept. of Forest Sciences, Faculty of Agriculture and Natural Resources, Ilam University, P.O. Box, 69391-77111, Ilam, I.R. Iran. 0000-0002-5867-3457 Eham Parvaneh 2Assisstant Prof., Dept. of Statistics and Mathematics, Faculty of Basic Sciences, Ilam University, P.O. Box, 69391-77111, Ilam, I.R Iran. Mehdi Omidi Assisstant Prof., Dept. of Statistics and Mathematics, Faculty of Basic Sciences, Ilam University, P.O. Box, 69391-77111, Ilam, I.R Iran. Journal Article 2025 08 25 Zagros forests play a significant role in carbon sequestration; however, the contribution of rare species such as Anagyris foetida L. (Ghareh Ghaj)—with unique traits such as thick leaves and summer dormancy—has been less studied. This research developed, for the first time, species-specific allometric models for this endangered tree to provide a non-destructive estimation of leaf carbon storage and LAI1. The study was conducted in the pure habitat of the species within the Sardasir Chaleh basin (Gilan-e-Gharb). Using systematic line sampling, 30 healthy trees were selected, and biometric parameters (height, crown diameter, and crown area) were measured. Leaf samples were collected from three crown sections and analyzed in the laboratory to determine dry biomass (gravimetric method), organic carbon percentage (combustion in a furnace), and leaf area (leaf area meter). LAI and SLA2 were calculated and scaled up to the forest stand level using the "Mean Tree" method and a density of 253 trees per hectare. Allometric relationships were analyzed using linear, logarithmic, and power regression models. Results showed that mean LCS3, CO₂ uptake, and leaf dry biomass per hectare were 468.13 kg of carbon, 1718.03 kg, and 975.27 kg, respectively. The average LAI at the individual-tree and per-hectare levels was 1.6 and 0.302, respectively. Statistical analyses revealed a strong and significant correlation between crown area and both leaf biomass and LCS, with the linear model based on crown area providing the best fit for predicting LCS (R² = 0.719). In contrast, LAI was only significantly correlated with leaf dry biomass. Overall, the results indicate that, despite its prolonged dormancy period, this species contributes considerably to leaf carbon storage in Zagros forests due to its relatively high density and distinct crown architecture. The simple, crown area-based models presented offer a practical and cost-effective tool for carbon monitoring, ecosystem service valuation, and the development of conservation strategies for this endangered species and similar Mediterranean ecosystems, representing a significant step toward sustainable forest management. Zagros forests play a significant role in carbon sequestration; however, the contribution of rare species such as Anagyris foetida L. (Ghareh Ghaj)—with unique traits such as thick leaves and summer dormancy—has been less studied. This research developed, for the first time, species-specific allometric models for this endangered tree to provide a non-destructive estimation of leaf carbon storage and LAI1. The study was conducted in the pure habitat of the species within the Sardasir Chaleh basin (Gilan-e-Gharb). Using systematic line sampling, 30 healthy trees were selected, and biometric parameters (height, crown diameter, and crown area) were measured. Leaf samples were collected from three crown sections and analyzed in the laboratory to determine dry biomass (gravimetric method), organic carbon percentage (combustion in a furnace), and leaf area (leaf area meter). LAI and SLA2 were calculated and scaled up to the forest stand level using the "Mean Tree" method and a density of 253 trees per hectare. Allometric relationships were analyzed using linear, logarithmic, and power regression models. Results showed that mean LCS3, CO₂ uptake, and leaf dry biomass per hectare were 468.13 kg of carbon, 1718.03 kg, and 975.27 kg, respectively. The average LAI at the individual-tree and per-hectare levels was 1.6 and 0.302, respectively. Statistical analyses revealed a strong and significant correlation between crown area and both leaf biomass and LCS, with the linear model based on crown area providing the best fit for predicting LCS (R² = 0.719). In contrast, LAI was only significantly correlated with leaf dry biomass. Overall, the results indicate that, despite its prolonged dormancy period, this species contributes considerably to leaf carbon storage in Zagros forests due to its relatively high density and distinct crown architecture. The simple, crown area-based models presented offer a practical and cost-effective tool for carbon monitoring, ecosystem service valuation, and the development of conservation strategies for this endangered species and similar Mediterranean ecosystems, representing a significant step toward sustainable forest management.

https://www.ijf-isaforestry.ir/article_243810_2dd654c9b596ce9a7ee01871ef35b23a.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 A New Method for Development of a Competition Index Using Crown–Diameter Relationship of Naturally Grown Pinus brutia Ten. in Iraq A New Method for Development of a Competition Index Using Crown–Diameter Relationship of Naturally Grown Pinus brutia Ten. in Iraq 611 631 243812 10.22034/ijf.2026.550576.2078 FA Abdulaziz J Younis Ph.D. Student, Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Duhok, Iraq. 0009-0005-6550-7800 Tariq K. Salih Assistant prof., Dept. of Forestry, College of Agricultural Engineering Sciences, University of Duhok, Duhok, Iraq. 0009-0004-6136-1560 Journal Article 2025 10 04 Introduction: Forests cover about 30% of the Earth’s land surface, but in Iraq they are limited, mainly confined to the northern region, totaling around 1.26 million hectares, or 2.9% of the country’s land area. Forests in this region include coniferous and broad-leaved types. Coniferous forests are dominated by pines, which make up approximately 80% of the stand. Calabrian pine (Pinus brutia), native to the Duhok governorate in northern Iraq, covers an area of approximately 50,000 ha in Zawita, Atrush, and Belkaf. This study deals with the regression of crown width on diameter at breast height to be used in the development of a competition index. Crown width is important for forest dynamics, biodiversity, carbon sequestration, and overall ecosystem health. Materials and Methods: Field data were collected from three distinct locations within Duhok Province, Kurdistan, Iraq. In total, 480 trees were sampled from both open-grown and stand-grown trees. A total of 160 trees were selected from each location (80 open-grown trees, which were free from all competition, and 80 stand-grown trees, where there was inter-tree competition regarding resource access). Of these, 50 trees were used for calibration, while 30 trees were used for validation, resulting in a balanced and robust dataset for analysis. Using Statgraphics Centurion 19 software, separate regressions of Crown Width (CW) against Diameter at Breast Height (DBH) were developed for both tree types. Six groups of allometric regression equations were evaluated using criteria that included the coefficient of determination (R²), bias, mean absolute error (MAE), Ohtomo’s unbiased test, and additional proposed metrics. Results: Crown width was regressed on diameter at breast height using different types of functions; among them, linear, nonlinear, and logarithmic models with different forms of dependent variables were used. Upon statistical analysis of the developed models, the linear model of the form, Cw = b₁ + b₂ DBH, was selected as the most appropriate one that fit the study data in both tree types across all locations. As a result, there was no major difference between the regression slopes for open-grown trees and those for trees growing within a stand. In addition, this study presented a new method for calculating the competition index. Conclusion: From the analysis of the samples collected, certain key conclusions can be drawn. First, in all the study sites, the relationships between crown width and diameter at breast height (DBH) did not show any statistically significant differences between open-grown and stand-grown trees. This indicates a relatively low stand density, resulting in minimal competition for resources among stand-grown trees. Second, given the improvement of overall forest structure and productivity, it is advisable that replanting strategies should fill the existing canopy gaps in all sites, since this will make better use of available resources, promote the long-term health of forests, and maintain biodiversity. Lastly, the present study confirmed a strong linear relationship between crown width and DBH for Calabrian pine in Iraq. Introduction: Forests cover about 30% of the Earth’s land surface, but in Iraq they are limited, mainly confined to the northern region, totaling around 1.26 million hectares, or 2.9% of the country’s land area. Forests in this region include coniferous and broad-leaved types. Coniferous forests are dominated by pines, which make up approximately 80% of the stand. Calabrian pine (Pinus brutia), native to the Duhok governorate in northern Iraq, covers an area of approximately 50,000 ha in Zawita, Atrush, and Belkaf. This study deals with the regression of crown width on diameter at breast height to be used in the development of a competition index. Crown width is important for forest dynamics, biodiversity, carbon sequestration, and overall ecosystem health. Materials and Methods: Field data were collected from three distinct locations within Duhok Province, Kurdistan, Iraq. In total, 480 trees were sampled from both open-grown and stand-grown trees. A total of 160 trees were selected from each location (80 open-grown trees, which were free from all competition, and 80 stand-grown trees, where there was inter-tree competition regarding resource access). Of these, 50 trees were used for calibration, while 30 trees were used for validation, resulting in a balanced and robust dataset for analysis. Using Statgraphics Centurion 19 software, separate regressions of Crown Width (CW) against Diameter at Breast Height (DBH) were developed for both tree types. Six groups of allometric regression equations were evaluated using criteria that included the coefficient of determination (R²), bias, mean absolute error (MAE), Ohtomo’s unbiased test, and additional proposed metrics. Results: Crown width was regressed on diameter at breast height using different types of functions; among them, linear, nonlinear, and logarithmic models with different forms of dependent variables were used. Upon statistical analysis of the developed models, the linear model of the form, Cw = b₁ + b₂ DBH, was selected as the most appropriate one that fit the study data in both tree types across all locations. As a result, there was no major difference between the regression slopes for open-grown trees and those for trees growing within a stand. In addition, this study presented a new method for calculating the competition index. Conclusion: From the analysis of the samples collected, certain key conclusions can be drawn. First, in all the study sites, the relationships between crown width and diameter at breast height (DBH) did not show any statistically significant differences between open-grown and stand-grown trees. This indicates a relatively low stand density, resulting in minimal competition for resources among stand-grown trees. Second, given the improvement of overall forest structure and productivity, it is advisable that replanting strategies should fill the existing canopy gaps in all sites, since this will make better use of available resources, promote the long-term health of forests, and maintain biodiversity. Lastly, the present study confirmed a strong linear relationship between crown width and DBH for Calabrian pine in Iraq.

https://www.ijf-isaforestry.ir/article_243812_2f2dea22c5d9e870f71925a65709c09f.pdf

Iranian Society of Forestry Iranian Journal of Forest 2008-6113 17 4 2026 02 20 Structure analysis of non-protected forest stands in Boyer-Ahmad County Structure analysis of non-protected forest stands in Boyer-Ahmad County 633 646 227249 10.22034/ijf.2025.511864.2048 FA Yousef Askari Assistant Prof., Research Division of Forest, rangeland and watershed, Kohgiluyeh and Boyerahmad Agriculture and Natural Resources Research and Education Center, AREEO, Yasouj, I. R. Iran Sayed Kazem Bordbar 2ssistant Prof., Research Division of Natural Resources, Fars Agriculture and Natural Resources Research and Education Center, AREEO, Shiraz, I. R. Iran Mehdi Pourhashemi Prof., Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, I. R. Iran Journal Article 2025 03 16 Quantitative descriptions of forest structure are recognized as one of the most effective tools in modern forest management. As such, obtaining accurate and comprehensive information about the structure of tree species is crucial for the sustainable management of forest ecosystems. This study, conducted as part of a comprehensive monitoring plan for the Zagros forests using place-based monitoring, evaluates the structure of two forest stands: Sarabtaveh on the northern slope and Parikadan on the southern slope in the forests of Boyer-Ahmad County, Kohgiluyeh and Boyer-Ahmad Province. In each stand, a one-hectare square sample plot was randomly established, and quantitative variables related to tree stems were measured. The findings revealed that the dominant tree form in both stands was coppice or branch-derived. The spatial distribution pattern of the dominant species, Persian oak, was clumped in both regions. The mingling index was calculated as 0.23 for Parikadan and 0.14 for Sarabtaveh, indicating higher species diversity in Parikadan compared to Sarabtaveh. However, the mingling index for both regions (study areas) was relatively low, which aligns with the fact that Persian oak is the predominant species in the studied areas. The Clark-Evans index was 0.61 for Parikadan and 1.13 for Sarabtaveh. The diameter differentiation index was 0.33 for Parikadan and 0.32 for Sarabtaveh, suggesting no significant difference in the average diameter at breast height (DBH) and highlighting the homogeneity of trees in terms of diameter. Additional measurements and calculations included the uniform angle index, diameter dominance indices, canopy cover, neighborhood distance index, and structural diversity index, among others. The results of these indices provide a valuable foundation for comparing the studied forests with other similar ecosystems and identifying deviations caused by natural processes and human activities. Such comparisons will contribute to the development of effective management models and appropriate forestry methods tailored to the region's forests. Quantitative descriptions of forest structure are recognized as one of the most effective tools in modern forest management. As such, obtaining accurate and comprehensive information about the structure of tree species is crucial for the sustainable management of forest ecosystems. This study, conducted as part of a comprehensive monitoring plan for the Zagros forests using place-based monitoring, evaluates the structure of two forest stands: Sarabtaveh on the northern slope and Parikadan on the southern slope in the forests of Boyer-Ahmad County, Kohgiluyeh and Boyer-Ahmad Province. In each stand, a one-hectare square sample plot was randomly established, and quantitative variables related to tree stems were measured. The findings revealed that the dominant tree form in both stands was coppice or branch-derived. The spatial distribution pattern of the dominant species, Persian oak, was clumped in both regions. The mingling index was calculated as 0.23 for Parikadan and 0.14 for Sarabtaveh, indicating higher species diversity in Parikadan compared to Sarabtaveh. However, the mingling index for both regions (study areas) was relatively low, which aligns with the fact that Persian oak is the predominant species in the studied areas. The Clark-Evans index was 0.61 for Parikadan and 1.13 for Sarabtaveh. The diameter differentiation index was 0.33 for Parikadan and 0.32 for Sarabtaveh, suggesting no significant difference in the average diameter at breast height (DBH) and highlighting the homogeneity of trees in terms of diameter. Additional measurements and calculations included the uniform angle index, diameter dominance indices, canopy cover, neighborhood distance index, and structural diversity index, among others. The results of these indices provide a valuable foundation for comparing the studied forests with other similar ecosystems and identifying deviations caused by natural processes and human activities. Such comparisons will contribute to the development of effective management models and appropriate forestry methods tailored to the region's forests.

https://www.ijf-isaforestry.ir/article_227249_d7aeb068fdc7e862a1b4cb3394e6ee02.pdf