جستجوی مقالات مرتبط با کلیدواژه « چرا » در نشریات گروه « جنگلداری »

In today’s urbanized world, the preservation of the environment and urban green spaces has become a major concern for citizens and governments worldwide. This study aims to emphasize the importance of non-governmental organizations (NGOs) and charitable foundations in the reforestation and afforestation of vegetation cover. Using a comparative approach, the study examines global and Iranian experiences and evidence, and reviews executive and functional records in the field of natural environments, vegetation, and green spaces through library surveys, internet research, and inquiries made to domestic and foreign institutions and organizations.

This study introduces some of the most significant charitable foundations and NGOs in the field of nature and environmental protection worldwide. These organizations, mainly based in the United States and England, have completed their education and entered the stage of implementing initiatives for the restoration of local forests, world forests, forestry, environmental protection, increasing biodiversity, climate change, and other related topics. Additionally, the study examines the forest reforestation and afforestation goals and implementation methods of the most important charitable foundations in countries similar to Iran, including Armenia, Turkey, and Lebanon, as well as different countries such as China, South Korea, Norway, Germany, Brazil, and Canada. The study also describes the activities of internal organizations such as Nature, Pama, Roostagol Varjin, and Algan, and analyzes their significant actions and measures taken. Finally, the role of certain charities that have taken action in restoring and developing vegetation in the country is discussed.

The results of this study showed that among the countries similar to Iran, the “Tema” Institute in Turkey, with a 30-year history at the national and international levels, has carried out significant activities in the fields of forest restoration, education, climate studies, and biodiversity. Among different countries, the “Terra” Institute of Brazil has also undertaken important measures in the fields of reforestation, wildlife return, and vegetation restoration, aiming to restore the region’s forests, environment, and promote sustainable rural development over a period of 20 years. Among domestic institutions, Roostagol Varjin has made a significant contribution to the reforestation and afforestation of vegetation and urban green spaces. All these institutions and foundations share common goals in their field of activity, and through the support and participation of these groups together, the great goal of vegetation reforestation and afforestation can be realized. Therefore, it is not possible to determine which activity is superior; all of them are necessary in society. In fact, for the development of this task globally and even within a country, we need a powerful society, and a powerful society requires the participation of more people, and the grounds for this participation must be provided.

To improve the status and activities of NGOs, several measures can be taken, including providing information and training, strengthening environmental advertisements on radio and television, expressing environmental problems, and providing banking and legal facilities for these organizations. Additionally, introducing native species for planting in each region, empowering local communities, establishing research units and experts in the field of reforestation and afforestation, and promoting communication between NGOs, donors, and the government are the most important management measures for restoring and developing vegetation at the national level.

Estimating forest tree structural attributes such as height and diameter at breast height (DBH) is crucial for understanding the structure and management of forest resources. One important method for estimating these parameters is the individual tree detection (ITD) method using appropriate remote sensing data, such as airborne LiDAR data. However, it should be noted that different ITD methods have various limitations and capabilities and react differently to changes in forest tree species and the vertical structure of the canopy.

This study presents a hybrid individual tree detection method that combines raster-based and point-based methods in a multi-scale framework to identify single trees from LiDAR data. In this method, tree crown scale levels are obtained from morphological filters in the canopy height model (CHM). Segmentation is then performed using a multi-scale method, and the results are merged. To better separate adjacent and understory trees, the point cloud inside the segments is analyzed using the probability density function, and tree crown segments are modified. After detecting single trees, DBH and height parameters were estimated using ground control data and extracted features from LiDAR data with machine learning algorithms, including random forest (RF), support vector machine (SVM), and cubist (CB), in the form of 10-fold nested cross-validation (10-fold NCV). The Boruta feature selection algorithm was used to identify the most important metrics based on the LiDAR point cloud, which played an effective role in improving the performance of machine learning algorithms. Due to limited access to LiDAR and ground data from Iran’s forests, this study uses the NEWFOR single tree detection benchmark dataset, collected from forests of the Alpine region with a combination of different tree species and vertical canopy structures.

Although understory trees cannot be extracted with the same accuracy as overstory trees, the results of this study showed that, on average, the developed multi-scale individual tree detection (MSITD) method detected 89% of the tree crowns in the highest height layer and the highest number of small overstory trees with a detection rate of 48% in the lowest height layer (2-5 meters). The analysis of the machine learning algorithms’ results in estimating forest structural attributes showed that, despite slight differences in performance, the SVM algorithm performed better than the RF and CB algorithms in estimating both height and DBH attributes. For the height attribute, the mean values of RMSE, rRMSE, and R2 in the SVM algorithm were 1.75 m, 9%, and 0.85, respectively. For the DBH attribute, the values obtained for RMSE, rRMSE, and R2 were 4.74 cm, 19%, and 0.78, respectively.

The evaluation of the results showed that the methods presented in this study for identifying single trees and estimating forest tree structural attributes have high potential for practical applications.

Reproduction (regeneration) is a fundamental process that drives the dynamics of a forest, occurring continuously in a healthy and natural forest with a specific spatial and temporal pattern. Natural regeneration poses significant challenges in Zagros forests, Iran. This research was undertaken to examine and analyze the current state of reproduction of tree and shrub species in the monitoring sample plots of Zagros forests. This study, while scrutinizing the species composition, origin, distribution curves, and health of seedlings and saplings, explores the interrelationship between reproduction and nurse species. It will serve as the foundation for long-term studies that determine the temporal changes in reproduction and its characteristics in the Zagros forests.

This research was conducted in the permanent monitoring plots of Zagros, spanning from West Azerbaijan to Fars province. A total of 120 sample plots of 100 square meters were studied within these plots. Each province had 30 studied sites in the typical forests, with 10 of them located in the protected forests. The variables studied included reproduction density by species, origin and type of reproduction, nurse species, height of seedling, terminal bud, and health status of reproduction. A height of 0.5 meters was set as the criterion to distinguish reproduction. The t-test was used to compare parametric data in two groups, while the Kruskal Wallis and Mann-Whitney U tests were employed for non-parametric data.

In the studied area, the reproduction of 20 forest tree and shrub species was recorded, and the density of seedlings and saplings was calculated to be 366 plants per hectare. However, the reproduction was not uniformly distributed, with 37% of the sample plots lacking reproduction. The abundance distribution diagram in the height classes revealed a decrease in the number of oak (Quercus spp.) and hawthorn (Crataegus spp.) reproduction with a height of less than 5 cm. Of the total number of recorded reproduction, 72.5% originated from seeds and 25% were shoots. Overall, 66% of reproduction was dependent on nurses, with oak, hawthorn, stone, and rock playing the greatest roles as nurses. Stones and rocks played a more significant role in the revival of seedlings. Cerasus microcarpa (C.A.Mey.) Boiss., Q. infectoria Oliv., and Q. libani Oliv. had the highest dependence on the nurse, while Pyrus spp., Daphne mucronata Royle, and Crataegus spp. had the least dependence on nurse species. Reproduction sheltered by nurses was significantly healthier than those without nurses. Also, reproduction sheltered by stones and rocks had a higher health rate than reproduction sheltered by trees, although this difference was not significant. Lonicera nummulariifolia Jaub. & Spach, Fraxinus angustifolia Vahl, and Acer monspessulanum L. had the worst condition in terms of reproduction. Despite the presence of mature trees, they had no reproduction (L. nummulariifolia and F. angustifolia) or had very low reproduction (A. monspessulanum). The results showed that the number of reproduction in protected sites was higher than non-protected sites. Although this difference was not significant, the reproduction in the protected sites was significantly healthier.

The results indicated that the reproduction in the Zagros forests is not in a normal situation. However, given suitable spatial and temporal conditions, reproduction occurs and establishes. Although in conditions of disturbance and overgrazing, reproduction attempts to survive by taking shelter near stones, pits, or under thorny shrubs, the conservation of the forest stand by maintaining the tree canopy (oak, hawthorn, and other species) and the forest’s natural structure provides the best conditions for the establishment and survival of reproduction, thereby ensuring the sustainability of the ecosystem.

Given the significance of investigating and monitoring riparian ecosystems, this study was conducted to identify and map the land cover, including tree and shrub species classes, around the Zarinehroud River in West Azerbaijan province, Iran. Recognizing that the separation of lands with high spectral similarity using single-time images is not precise, this study utilized a time series of satellite images, capitalizing on the phenological differences of plant species.

The research separated the land cover classes into two stages. In the first stage, the time series data from Sentinel 1 and 2 were used to map different classes of tree cover (natural, wood farming, orchard), shrub cover (natural, orchard), grass or pasture, agriculture, residential lands, soil, and water bodies. Given that seasonal changes in the images can provide valuable information about land cover classes, a one-year (2021) time series of Sentinel 2 optical images and Sentinel 1 radar polarizations for 2021, in the form of median in each season, were processed on the Google Earth Engine platform. The data were classified using four composites of input features and four classifiers. In the second stage, to separate the vegetation classes into Tamarix, willows, orchard, and poplar plantation, the trend of one-year changes of normalized difference vegetation index (NDVI), normalized green red difference index (NGRD), normalized difference red edge index (NDREI), and green normalized difference vegetation index (GNDVI) combined with HV polarization of Sentinel 1 radar in the form of median in seasons, was used as an input feature. The land cover map produced contained Tamarix, willows, orchard, poplar plantation, grass or pasture, agriculture, residential lands, soil, and water bodies.

In the first stage of classification, the input feature of NDVI (Monthly)_ Radar (Seasonal)_ Sentinel 2 (Seasonal) and the random forest classifier were the best feature and the most accurate classification algorithm, separating the classes from each other with an overall accuracy and Kappa coefficient of 88% and 0.85, respectively. In the second stage of classification, the NDVI index between the months of April and November enabled the separation of all four tree and shrub covers. GNDVI between December and April was the best indicator for separating willows. Also, between May to November, it effectively separated Tamarix. NGRDI was suitable between May and November for separating Tamarix and also separated the poplar plantations between April and November. The GNDVI index between April and September effectively separated the two categories of orchards and poplar plantations from Tamarix and willows. The map was generated using the mentioned input feature and random forest algorithm. The overall accuracy and Kappa coefficient obtained from the validation relying on ground samples and Google Earth images were 80% and 0.77, respectively. The main diagonal of the error matrix shows the highest separation between water, soil, and urban land classes. Among the vegetation classes, willows and agricultural lands exhibited the best distinction.

The variation in a plant’s phenology, encompassing leafing, blossoming, fruiting, fall, and sleep cycle, leads to changes in the values of vegetation indicators during the seasons, which can be utilized in mapping vegetation to enhance separability. Consequently, if tree and shrub stands are pure and exhibit a different phenological behavior from their neighbors, they can be distinguished with higher accuracy using time series of satellite images.

Different plants from different climates are collected according to the objectives of botanical gardens. Climate is one of the important ecological factors that has the greatest impact on the longevity of plants. Changing the location of the plant from a dry to a humid climate may cause stress and change in vegetative behavior. Therefore, the selection of plants for each region should be based on climate knowledge. The objectives of this research included investigating the effect of climate and nutritional treatments on the growth of wild almond (Prunus scoparia Schneider).

This research was conducted by two related experimental methods. One of which included investigating the effect of climate on the growth of wild almond in Nowshahr Botanical Garden in Nowshahr county in north of Iran and the other one was the nutritional treatments on the seedlings of the wild almond in the Garden. The investigated factors in the climate effect test included the species of wild almond, environmental indicators and soil. The nutritional treatments were carried out as a completely randomized factorial design in three replications in the nursery section that the test factors were three levels of calcium nitrate as foliar spraying with a concentration of zero (control), 5 and 7.5 mM and two levels of potassium sulfate as foliar spraying with a concentration of zero (control) and 6 mM. The time of conducting this research was from 2017 to 2022. The seeds of the wild almond species were collected from the heights of Ghatour valley from Rahal village to Ghatour district located in Khoy county, Iran with an altitude range of 1492 to 1873 meters above sea level. Some parameters related to soil, plant and climate were evaluated at the same time as the experiment started in Nowshahr and Khoy counties. After the seeds germinated and the seedlings emerged from the soil, nutrition treatments were carried out by spraying potassium sulfate and calcium nitrite.

The results of the experiments showed that Nowshahr's climate had a significant effect on the growth indicators of almond species from temperature, humidity, evaporation, sunny hours and ice days. The highest photosynthesis rate of 2.45 mg/fresh weight and the highest plant transpiration rate of 1.35 mmol/square meter per second were observed in Khoy climate. The lowest root length in Nowshahr Botanical Garden was 63.32 cm with the highest share of leafless branches at 60.98%. Correlation relationships of root length in the soil and the intensity of leaf fall (leafless branches) show a significant positive correlation at the 1% level with the amount of plant transpiration. The results of the test data showed that the use of potassium sulfate compared to the control seedlings, led to an increase in the amount of plant growth and, as a result, expanded the canopy width. In this research, the relationship between calcium absorption and transport in the plant showed that the reduction of calcium in the leaf tissues in the control seedlings decreased the resistance of the plant to maintain the leaves. Calcium foliar application increased the amount of calcium in leaf tissue in almonds. One of the effects of this phenomenon is the increase in the durability of almond seedlings to about 30%.

Foliar treatments of potassium and calcium nutrients, although to some extent increased the durability of almond seedlings during the experiment, but the growth disorders caused by the effect of climatic factors prevailed over the nutritional treatment. Therefore, the seedlings could not successfully adapt to the new environment even with the help of nutritional behavior.

Forest roads are essential infrastructures for accessing and managing forest units. Sustainable road management requires accurate spatial information from the road network. Various methods, differing in accuracy, precision, efficiency, and cost, are available for providing the location of roads. Given the remote location of forest roads, the lack of reference stations, potential inaccessibility to online networks, and conditions affecting positioning error, it is necessary to investigate the efficiency of existing positioning methods.

In this research, we studied the accuracy of PPK, RTK, online platforms such as Shamim, GPS, and mobile apps in positioning 34 points on 5 km of forest roads in watershed No. 30 in the Hyrcanian forest. The coordinates were first extended to the study area using the rapid static method. After post-processing and determining reference points, the exact coordinates of all ground control points on the road were obtained through the direct method. Then, the coordinates of all points were measured three times using various methods.

The health survey's statistical results showed that the highest mean differences were 2.53 m and 2.38 m for GPS and mobile apps, respectively. The least mean difference was 0.048 m, 0.049 m, and 0.092 m for PPK, RTK, and Shamim, respectively. The RMSE amount showed that the results from GPS and mobile apps had the least accuracy, and the methods PPK, RTK, and Shamim had the highest. Based on the one-sample T-test and Wilcoxon’s analysis, the amount of differences was not the same within each method through the 34 investigated points. Accuracy analysis indicated that GPS, with a distance mean of 1.14 m, had the least precision, and Shamim and RTK, with 0.0621 m and 0.063 m, were the most precise methods. The analysis of variance showed that the mobile app, Shamim, and PPK had the highest convergence.

The results of this research indicate that the PPK method was the most accurate, and the Shamim method was the most precise. Therefore, these methods can be used for purposes such as optimizing the forest road plan and longitudinal profile that require accurate location information.

The implementation of the forest restoration plan in the northern region of Iran has led to an increase in efforts to enhance wood production through the cultivation of poplar seedling. Particularly, poplar trees hold a significant position among wood producers due to their distinctive features. The key consideration revolves around identifying suitable and cost-effective lands for planting fast-growing species. Purpose of this study focuses on assessing the land suitability for poplar (Populus nigra L.), a prevalent forest species in the country, through a quantitative land evaluation method based on the FAO approach.
The research gathered and classified the edaphic and climatic requirements of poplar tree by utilizing various library resources, data from the soil laboratory of the Research Institute of Forests and Ranglands, and field survey (Soil Profiles). The climatic and soil characteristics were quantitatively classified into five categories: highly suitable (S1), moderately suitable (S2), low/critically suitable (S3), The Quantitative Classification of soil and climate properties was done in five classes: suitable (S1), moderate suitability (S2), low or critical suitability (S3), currently not suitable (N1) and permanent not suitable (N2). For validation, a quantitative assessment of land suitability for poplar cultivation was performed across six soil types, including Nowshahr forest brown, Nowshahr gray brown pedzolic rich in organic matter, Chamestan alluvial regosol, Chamestan Rendezina, Chalous  Pseudogley , and Karaj alluvial cambisol, using a parametric method (second root).
Results indicate that spruce thrives in wet and semi-humid regions in a dry-type manner, with ideal conditions found in areas receiving 1500-1800 mm of rainfall. In drier, semi-arid zones, irrigation is essential for meeting water requirements. Optimal growth temperatures for spruce range from 11-16 degrees Celsius in moderate climates. Poplar flourishes in soils with a light to medium texture, granular or cubic structure, good to fast drainage, and low underground water levels with adequate calcium and magnesium cations.
The study showed that the most suitable soils for poplars have a light to medium texture with a granular or crumb structure, with adequate drainage, the absence of high groundwater and the sufficient amount of calcium and magnesium cations in the soil. Soils with incomplete drainage and heavy texture do not provide suitable conditions for poplar plantations. In terms of quantitative evaluation, Mollic Udifluvents soils with medium texture had the highest score for poplar plantations.

The aim of this study is to investigate the performance of various algorithms in enhancing the accuracy of land cover maps using Sentinel images.

The study area is a sheet (1:25000) encompassing an area of 15782.6 hectares. The land cover map was created using a range of algorithms - Mahalanobis distance, maximum likelihood, minimum distance, neural network, parallelepiped, support vector machine, spectral angle mapper, spectral information divergence, and binary encoding - applied to the optimal band composition derived from 12 bands (2, 3, 4, 5, 6, 7, 8, 8a, 11, 12, NDVI, SAVI). The training area was obtained from field information and satellite images. 70% of the samples were used for classification and 30% for evaluating the accuracy of the classified maps.

The results indicate that the support vector machine, neural network, and maximum likelihood classifications have the highest accuracy. The support vector machine classifier is slightly more accurate than the other two classifiers. To improve the classification, support vector machine kernels (linear, polynomial, radial basis function, and sigmoid), spectral angle mapper settings (6 modes), and parallelepiped (2 modes) were utilized. The results show that the support vector machine classifier, using the 6th degree polynomial function method, has the highest accuracy. Following this, the map was post-processed with the highest accuracy, resulting in an overall accuracy of 96.63 and a kappa coefficient of 0.9393.

An examination of 21 classification modes on Sentinel images in this study provides a comprehensive review of classification algorithms compared to previous studies.

The mechanical characteristics of roots can serve as a significant factor for selecting trees in the plantation of arid regions for soil bioengineering. This research aims to evaluate the mechanical characteristics of Tehran pine roots at various vegetative ages (one-year-old, three-year-old, and five-year-old seedlings) and under different water stress levels (light, medium, and severe) in Robat Karim. The mechanical properties of the roots were studied after estimating the water requirement of the studied seedlings at different ages for one year and based on the water stress levels. Then, five seedlings from each treatment (equal to 9 treatments) were selected and coded completely randomly to evaluate the water stress on the mechanical characteristics of the roots of Tehran pine. Initially, some root parameters such as root diameter, length of the whole root, length of thin roots, and length of the longest root were measured. Then the tensile force, tensile strength, and Young's modulus of the roots were measured and recorded using a standard Centam device. The results showed that with the increase in root diameter, the tensile force of the root changes based on the positive power relationship, and the tensile strength and Young's modulus of the root changes based on the negative power relationship. Furthermore, laboratory examinations showed that at any age, the length of the whole root and the root length densities are higher with the increase in water stress. The use of covariance analysis showed that the results of the average comparison between one-year-old age and mild drought stress, three-year-old age and moderate stress, and five-year-old age and severe stress are significant with a probability of 95%. The results of this research show that the mechanical characteristics of the root can be used as an important factor for the selection of pine seedlings in the afforestation of arid areas for soil bioengineering purposes. Therefore, it is recommended that these properties be considered in soil reinforcement modeling.

Monitoring the nutrients of tree leaves is crucial for understanding their physiological responses to environmental stresses. This study monitored the status of leaf nutrients in Persian oak trees (Quercus brantii Lindl.) affected by crown dieback during the years 2019-2021.

Two sites, one northern and one southern, were selected in the Mele-Siah area. Five healthy trees and five declining trees were identified at each site. From each tree, 20 mature and healthy leaves were collected and taken to the laboratory to measure the concentration of nitrogen, phosphorus, potassium, calcium, and magnesium elements. Leaf sampling was conducted annually in August over three years. Soil sampling was also conducted during the growing season over three years, with a hole dug on the southern side of each tree crown to measure soil moisture in two horizons.

The results showed that the amount of leaf nitrogen was highest (1.48%) in 2019 and lowest (1%) in 2020, and it was higher in healthy trees (1.30%) than in declining trees (1.22%). The amount of phosphorus was higher in the northern site in all years. The amount of potassium was highest (2.22%) in 2019 and lowest (0.58%) in 2020. The amounts of leaf calcium and magnesium were highest (1.8% and 2.36% respectively) in 2019 and lowest (0.57% and 0.69% respectively) in 2021. Furthermore, the amount of calcium was higher in the northern site (1.29%) than in the southern site (0.99%). The highest amount of calcium was found in declining trees (1.465%) in the northern site and in healthy trees (1.241%) in the southern site. The results also showed that soil moisture was higher in the northern site in all sampling years and was associated with annual changes, which affected the changes in leaf nutrients over different years.

Considering the differences in soil moisture, soil acidity, and salinity of the studied sites, as well as temporal changes in the concentration of leaf elements caused by climate changes, it can be concluded that the crown dieback of Persian oak trees is related to the physiological mechanisms involved in water and nutrient absorption.

Deadwood, at various stages of decay, serves as a diverse habitat for a wide range of species. This study investigates the diversity of macrofauna orders on fallen hornbeam deadwood with different decay classes (four classes) in district one of the Shast Kalate forest in Gorgan, Iran.

Samples were collected from 108 deadwood logs across three altitudinal ranges (200-450, 450-700, and 700-950 m a.s.l.) with three replicates for each decay class and diameter class (less than 40, 40-80, and more than 80 cm). Macrofauna were manually extracted from the deadwood and weighed to the nearest 0.001 g after identification using systematic keys. The diversity of macrofauna orders was assessed using diversity (Shannon-Wiener), evenness (Simpson), and richness (Margalef) indices.

The results revealed significant differences in mean richness, biomass diversity, and abundance of macrofauna among the different decay classes of fallen hornbeam deadwood, with higher decay intensity associated with increased macrofauna richness and diversity. The highest number of macrofauna was found in decay class four and in the 70-100 and 40-70 cm diameter classes. Macrofauna order frequency was highest in the 200-450 m altitudinal range and lowest in the 700-950 m range, with no significant difference between the first two altitudinal classes. A significant negative relationship was observed between deadwood length and macrofauna order frequency.

As altitude increased, biomass evenness increased while biomass richness decreased, suggesting that these factors counteracted each other, resulting in no significant difference in macrofauna order biomass diversity across the different altitudinal ranges.

Nitrate (NO-3) is an important compound in plant nutrition. However, the leaching of large amounts of it can reduce soil fertility and endanger environmental health and quality of life.

This study was conducted to investigate the effect of rice husk biochar and different types of pure and mixed fertilizers on nitrate leaching from the soil of one-year-old potted saplings of Acer cappadocicum Gled (with an average collar diameter of 17.3 mm and a height of 19.72 cm). This research was conducted in Lajim nursery, north of Iran, using 19 treatments with three replications in a completely randomized design. The treatments included rice husk at 0.5% and 1% by volume, biochar of rice husk at 0.5%, 1%, and 2% by volume, cow manure at 0.75% and 1.25% by volume, and chemical fertilizer at two levels: 1) triple superphosphate 25, ammonium sulfate 18.75, and potassium sulfate 18.75 mg per kilogram of soil and 2) triple superphosphate 50, ammonium sulfate 37.5, and potassium sulfate 37.5 mg per kilogram of soil. The soil treatment of the planting bed (control) and the combination of treatments were also included. To collect drainage water for measuring the amount of nitrate leaching, potted seedlings were irrigated 20% more than the normal irrigation amount, and samples were taken in five stages (from April to September, once before adding ammonium nitrate fertilizer and four times after its addition). In the laboratory, nitrate concentration was measured by the spectrophotometric method. Statistical analysis was performed using R software, and a comparison of means was performed using Duncan's test.

According to the results, in the first stage of sampling, the highest concentration of nitrate in drainage water was observed in the chemical fertilizer level 2. In the second and fourth stages, it was observed in the combination of chemical fertilizer level 1 and 0.75% cow manure by volume, and in the third stage, it was observed in the treatment with 0.75% cow manure by volume. The highest pH value of the drainage water in the first stage of sampling was observed in the combination of chemical fertilizer level 1 and 0.5% biochar. In the second and third sampling stages, the control showed the highest pH value. In the fifth stage, the result was the same as the first stage. Also, the combination of chemical fertilizer level 1 and 0.75 percent cow manure caused an increase of 204, and 0.5% biochar caused a total decrease of 39.4 mg/liter of nitrate leaching.

The results of this research showed that the application of biochar causes a decrease in electrical conductivity and nitrate concentration and an increase in the pH of drainage water. Therefore, considering the beneficial effect of biochar in reducing nitrate leaching and soil salinity, which will definitely bring positive environmental effects, it is recommended to use rice husk biochar to produce seedlings in forest nurseries.

Accurate digital elevation models (DEMs) are crucial for effective forest planning and management. Various methods exist for generating DEM data, with handheld mobile laser scanners being the most efficient and precise approach. The raw point clouds obtained from these scanners require several preprocessing steps, one of which involves separating ground and non-ground points. Errors in this part of the process can lead to the generation of an inaccurate digital model with high uncertainty and errors. Various algorithms, such as voxel-based segmentation, simulation filters, and deep learning-based approaches, have been developed for this purpose. This study evaluates the performance of the OBS algorithm in automatically separating ground points from non-ground points in handheld laser scanner data. The study area comprised five different sections within the Karaj Botanical Garden, covering a total area of 7.2 hectares. These areas contained forest stands characterized by heterogeneous structures and multi-story tree layers. Data were acquired using a handheld GeoSLAM laser scanner. To generate a reliable reference for evaluating the algorithm's results, ground points were manually separated. The performance of the algorithm was evaluated by comparing it with the manually separated ground truth using statistical metrics, including Matthew's correlation coefficient, Kappa coefficient, and Intersection over Union (IoU). The statistical metrics across the five study areas demonstrated the effectiveness of the OBS algorithm in separating ground points from non-ground points, with Matthew's correlation coefficient, Kappa coefficient, and IoU values of 0.895, 0.891, and 0.902, respectively. Additionally, the optimal voxel size for the algorithm was determined to be within the range of 15 to 22 centimeters.We conclude that the OBS algorithm, when configured with optimal input parameters, provides high performance in automatically separating ground points from non-ground points, especially in heterogeneous forested environments. The importance of configuring the optimal input parameters is also highlighted.

Cytogenetic investigations in plant species, particularly wild and native plants, are crucial for understanding their evolutionary history, establishing species relationships, and determining karyological features. This study delves into chromosome counting and evaluation of karyotypic characteristics of five woody species belonging to three families: Ulmaceae, Cornaceae, and Rhamnaceae within the Hyrcanian Forests. Root tip meristem was used for chromosomal studies by classical methods. The results revealed that all studied species were diploid. The chromosome numbers of three species, Cornus australis (2n=2x=22), Rhamnus sintenisii (2n=2x=26), and Zelkova carpinifolia (2n=2x=28) were documented for the first time in the world. Additionally, two species of Ulmus glabra and U. minor with a chromosomal number (2n=2x=28) were reported for the first time in Iran. Concerning chromosomal length, R. sintenisii displayed the smallest chromosome length (0.9 µm), while U. glabra exhibited the largest (2.34 µm). The chromosomes in three species, R. sintenisii, U. glabra, and Z. carpinifolia were of the metacentric and sub-metacentric types. U. minor presented sub-telocentric chromosomes in addition to the mentioned types, and C. australis displayed metacentric chromosomes in two forms, M and m. Regarding symmetry, chromosomes in three species, R. sintenisii, U. minor, and Z. carpinifolia were classified as 2A, C. australis as 1A, and U. minor as 3A. Given the scarcity of similar studies on forest species, this research significantly contributes to identifying the cytogenetic characteristics of the examined species.

Chestnut (Castanea sativa Mill.) is one of the native species of Guilan province. Due to fungal diseases and animal grazing, as well as the high amount of unhealthy seeds, native chestnut in vitro culture is one of the effective methods for mass production of this endangered plant. The aim of this research is to determine the optimal culture medium for chestnut tree regeneration through tissue culture. The culture medium used in this research includes GD (Gresshoff & Doy), DKW (Driver and Kuniyuki Walnut) (1 mg/liter BA*) and (Murashige Skoog) MS (half nitrogen concentration) with three different hormone combinations (1 mg/liter + BA 0.1 mg per liter TDZ), (0.5 mg/liter TDZ), and (1 mg/liter + GA3 0.1 mg/liter BA). For in vitro culture of chestnut, lateral buds of one-year-old plants grown in the greenhouse were used. One-way analysis of variance (ANOVA) was performed to investigate the effect of culture media with plant growth regulators on explant length, number of leaves, and stems. The results showed that the length of explants has a significant difference in culture media. No significant difference was observed in the number of stems and leaves. The results of the comparison of means using Tukey's test showed a significant difference between the length of explants in DKW medium and other media. DKW medium with 1 mg/liter BA was found to be the best medium for regeneration and longitudinal growth of chestnut explants. In the present study, in vitro culture of Chestnut is introduced an effective method for mass production of this species.

Chainsaws, which are widely used in tree felling operations, create vibrations. Long-term and intense exposure to vibration may lead to the development of vascular, neurosensory, and musculoskeletal disorders in the upper limbs of chainsaw workers, known as Hand-arm vibration syndrome. This study investigates the vibration levels during tree bucking operations on poplar trees with the MPTMGS5803 chainsaw model, one of the most widely used chainsaws in forest operations in the western part of Guilan province. Simultaneous vibration measurements in three directions (x, y and z) were carried out using the SVANTEK 106A vibration meter, aiming to determine the total amount of chainsaw vibration and the daily exposure period. The results show that the highest amount of vibration was measured in the x (1.61±0.62), (2.01±0.90) direction and the lowest in the y (1.48±0.17), (0.73±0.09) direction both in the rear handle and front handle of the chainsaw. The rear handle of the chainsaw had a higher overall vibration acceleration (3.05±0.54 m/s2) compared to the front handle (1.94±0.53 m/s2). In terms of the daily exposure period, the level of vibration exposure inflicted on the chainsaw operator during a  three-hour and 70 second working period amounted to 1.19 m/s2 in the front handle and 1.87 m/s2 in the rear handle, with both values falling within the permissible vibration range.

Different methods have been developed for the heat treatment of wood. Oil heat treatment (OHT), as a unique method, can provide a dry and oxygen-free heating medium. This study used a pilot-scale oil heat treatment to treat poplar wood at different temperatures to enhance its weathering resistance. Poplar timber was subjected to oil heat treatment using a specific heating program at three target temperatures (180, 190, and 200 °C), each held for two hours. The specimens were prepared and subjected to 1000 hours of accelerated weathering with a Gardner wheel. Water absorption and volumetric swelling were also determined during seven days of soaking in water. Contact angle measurements of water droplets, colorimetry, and ATR-FTIR analysis were also conducted before and after weathering. The dimensional stability of treated wood increased with higher processing temperature. Although the water absorption values of treated wood were lower than those of the control specimens, the difference was not significant. The samples exhibited an obvious color difference before weathering due to oil heat treatment, but their color changed to silver-gray tans after weathering. The maximum ∆E value after weathering was observed in the samples treated at 200 °C. Weathering increased the wettability of wood surfaces, but the treated samples still had a higher water droplet contact angle than those of the control sample. ATR-FTIR results determined that oil heat treatment is not an effective method for preventing the degradation of lignin in wood surface exposed to weathering factors.

The paper is a thin, wide sheet formed from the entanglement, flocculation, and bonding of fibers, filaments, and cellulose components. It is produced in various dimensions for numerous applications. Building on a previous study on the fluorescent staining methods of cellulose fibers, the present research investigates the microscopic structure of the sheet and its components in three dimensions (length, width, and depth) using a confocal laser scanning microscope. This study also examines the distribution of cellulose fibers and components within the paper structure's three dimensions using fluorescent properties and confocal microscopy. The cellulosic components of the paper structure exhibited a green fluorescent reflection (420-500 nm) in the visible light region when excited at a wavelength of 405 nm. Beyond the two-dimensional analysis of paper planes, the confocal laser scanning microscope provided a wide array of intriguing images, revealing how fibers or cellulose fiber fractions are distributed within the paper's thickness without the need for layer-by-layer slicing. Depth imaging of paper was successful for samples with basis weights of both 20 and 60 g/m². The resulting images showed increased flocculation and accumulation of fiber elements and segments with depth. Overall, images obtained from the confocal laser scanning microscope demonstrated that the apparatus is suitable for investigating the distribution of labeled fibers and fiber fractions in all three dimensions of the paper structure.

The beneficial characteristics of endophytic bacteria in general and environmental safety features of Bacillus spp. in particular, have made them potentially efficacious bacteria for plant growth promotion as well as plant defense elicitation against biotic and abiotic stresses. Given that the preservation of biodiversity and sustainability of the Hyrcanian forests in Iran is of utmost importance ecologically and environmentally, proper management of this ecosystem demands considerable attention and care. Studying the microbiome structure and activities, including determination of microorganisms living as endophytes or commensals can be regarded as the starting steps in this context. This study was aimed at the molecular identification and physiological characterization of endophytic Bacillus isolates recovered from the roots of hornbeam (Carpinus betulus L.) trees in some different locations of Hyrcanian forests.

Samples of hornbeam roots were randomly collected from Mazandaran and Golestan provinces, Iran, in the early spring of 2020. Root segments were surface-disinfected, washed in sterile distilled water (SDW) and crushed in drops of SDW using a sterile mortar and pestle. Isolation of bacteria was done by spreading drops of the suspension on plates of tryptic soy agar (TSA). Single colonies were selected after 3-4 days of incubation at 28˚C and restreaked on TSA to obtain pure cultures. Initial identification of the isolates was based on colony morphology, Gram-stain reaction, position of endospores, and production of catalase and oxidase. The isolates were characterized phenotypically and their diversity was assessed by comparing their DNA fragment patterns following their amplification by REP-, BOX- and IS50-PCR and electrophoresis on agarose gels. The data were converted into a binary matrix using TotalLab TL120 software, where the digits 1/0 represented the presence/absence of a DNA band. The similarity matrix and clustering were generated by the use of NTSYS 2.02e software based on the unweighted pair group method with arithmetic average (UPGMA) clustering algorithm. A representative isolate was selected for each of the DNA profile groups and a fragment of the 16S rRNA and HSP60 genes of each was amplified by PCR. PCR products were sequenced by Microsynth company (Switzerland) through the Sanger sequencing method. The nucleotide sequences were aligned and compared with those of a collection of Bacillus species retreived from GenBank using the BLASTn program. Phylogenetic trees were constructed using the Maximum-Likelihood and Neighbor-Joining methods with 1000 bootstraps in MEGA X software package. Antibacterial activity of Bacillus isolates against Brenneria roseae, the causal agent of hornbeam wetwood disease, was investigated using sterilized blank paper disk impregnated with extracts prepared in dichloromethane. The isolates were assessed for their capacity to produce Indole acetic acid (IAA), hydrogen cyanide, protease, and biofilm.

Thirty bacterial strains were isolated from hornbeam roots on TSA medium and subsequently characterized. The absence of bacterial colonies on the TSA plates inoculated with the final rinse water from the uncrushed bark fragments indicated the effectiveness of the surface disinfection procedure. The isolates were grouped into three clusters based on their phenotypic and genotypic characteristics. Comparison of the nucleotide sequences of the 16S rDNA and HSP60 with the sequences obtained from GenBank (NCBI) led to the identification of Bacillus thuringiensis, B. subtilis, and B. mycoides as the species constituting the three clusters, with B. thuringiensis being the predominant group. B. subtilis was the most populated and B. mycoides the least encountered species. Phylogenetic analysis based on the HSP60 gene sequence proved to be a reliable approach for determining the Bacillus species. IAA production level varied from eight to 75 mg/L among the species, with B. mycoides isolates producing the highest and B. subtilis the lowest levels of IAA. Most of the isolates had the capability to produce lipase, gelatinase, lecithinase, protease, and amylase. The isolates of B. thuringiensis produced higher levels of protease than the rest of the isolates. Biofilm production was particularly prominent in isolates of B. subtilis. The dichloromethane extract of B. subtilis isolate rAqa2 exhibited the highest growth inhibition (18.3 ± 0.25mm in diameter) of Brenneria roseae.

A high level of genotypic and phenotypic heterogeneity existed among the endophyte isolates recovered from the roots of C. betulus, despite their isolation from a common source species. This could be partly justified by viewing the Hyrcanian forests as a mixed-species ecosystem and a source of microbial consortia that could protect plants against stresses. This study is the first investigation on the molecular identification and characterization of endophytic Bacillus isolates from hornbeam roots in Iran.

Future studies, an essential knowledge domain, can aid in creating a better future for ourselves and our society. This study investigates the factors affecting forestry projects in central Zagros, Iran, using a Future Studies Approach. This applied research utilizes analytical approaches and exploratory techniques over a 25-year horizon.

This research was conducted in the central Zagros forests, specifically in Chaharmahal and Bakhtiari province. The data collection method employed in this research encompassed document analysis and questionnaire implementation. Initially, documents and guidelines for monitoring and evaluating natural resource management plans were utilized to collect the required information. Subsequently, a set of factors affecting the implementation of forestry projects were identified. From these factors (68 in total), 18 effective factors were selected through interviews with forest experts (academics and practitioners) and input into the MicMac software as a matrix of reciprocal effects. This was done by 15 experts with over 10 years of experience in implementing forestry projects in the central Zagros. These experts included those from the Department of Natural Resources and Watershed Management of Chaharmahal and Bakhtiari Province, the Office of Forests Outside the North in the Organization of Natural Resources and Watershed Management of Iran, and professors from the Department of Forestry at Shahrekord University. They were selected by targeted sampling. The degree of relationship between the variables, based on influence and effectiveness, was scored from zero to three. The scores were then averaged and entered into the MikMak software as a cross-impact matrix.

The results obtained showed a matrix density of 89.19%, indicating that the selected variables had a significant and diverse impact on each other, resulting in an unstable system. Out of a total of 324 relationships, 35 had zero influence, showing no cross-impact between the variables. There were 82 relationships with low impact, 132 with medium impact, and 75 with high impact. The matrix analysis of direct influence revealed that the coordination of officials with local people and the use of pioneer species were among the regulatory variables. Factors such as restoration, breeding operations, understory agriculture, grazing, and identification of local users were among the independent variables. The selected effective factors were categorized into four components: economic, social, forestry, and management. Based on the analysis of direct effects, factors such as income, livelihood, employment, public protection, public trust in officials, use of non-wood forest products, empowerment of local communities, participation of local communities, provisioning services, and regional development were identified as effective factors in the implementation of forestry projects. Based on the analysis of indirect influences, the participation factor had a very strong effect on development and people’s trust in officials. The local people’s participation factor had a strong effect on empowerment, and the development factor had a strong effect on livelihood.

The most significant problems in the forestry projects of Zagros are socio-economic issues, primarily because the implementation of these projects has not yielded economic benefits for the forest dwellers. The success or failure of activities related to the implementation of the forestry plan in any region depends on the economic level of local communities, their level of trust in officials, and the participation or non-participation of stakeholders in the same region. This is achieved when the role of local communities is clearly defined and assigned.