Hyrcanian Forests Of Iran Research Articles

PaRaVis: An automatic Python graphical package for ensemble analysis of plant beta diversity using remote sensing proxies

The ongoing impacts of climatic changes, coupled with intensified human activities, are leading to a significant loss of plant diversity, prompting urgent calls for comprehensive monitoring of forest ecosystems. This is particularly concerning in regions with the encroachment of human activities into forest zones, and inadequate regulations that primarily view forests as a source of timber without fully accounting for their critical roles in biodiversity. These issues highlight the need for effective geospatial approaches to support conservation strategies and sustained monitoring of plant diversity. The majority of remote sensing studies of plant diversity have focused on alpha-diversity, while beta-diversity plays an important role in providing a comprehensive picture of biodiversity patterns across scales. Among various remote sensing proxies, Rao's Q index stands out as a reliable metric to quantify beta-diversity using multispectral remote sensing indices. However, a holistic approach that can incorporate multiple remote sensing indices and enable comparative analysis using graphical means with computational efficiency is lacking. In response, we developed PaRaVis, an open-source Python-based graphical package for deriving spectral diversity from multispectral remote sensing datasets as a proxy for functional diversity using Rao's Q index. This tool encompasses all the necessary steps for parallelized computation, visualization, and analysis of Rao's index from either single or multiple multispectral indices. It is capable of calculating and visualizing 75 vegetation indices (VIs), from a raster scene, followed by calculating Rao's Q both unidimensionally and multidimensionally in parallel. PaRaVis also offers features for visualizing, analyzing, and comparing Rao's Q outputs using statistical performance diagnostics. It provides a unique means to infer diversity patterns in space and time and is therefore invaluable for researchers or organizations involved with plant diversity monitoring, especially those with limited data analysis or computer programming experience. To demonstrate the tool's effectiveness, we analyzed plant diversity patterns using satellite-derived spectral heterogeneity measures in forest sites within the Hyrcanian Forests of Iran and sites located in Germany. The first case study focused on UNESCO Natural Heritage sites. Our analysis revealed that employing EVI, SR3, and TCI indices as inputs for the multidimensional Rao's Q yielded higher performance in monitoring more heterogeneous forests compared to the unidimensional mode. In the second case study, we utilized field Species Richness and Shannon-Wiener diversity indices to evaluate PaRaVis and our method. We found that using a multi-temporal, multi-index approach enhances the results compared to multi-seasonal and classical Rao based on single time.

Satellite-based ensemble intelligent approach for predicting forest fire: a case of the Hyrcanian forest in Iran.

A machine learning-based approach is applied to simulate and forecast forest fires in the Golestan province in Iran. A dataset for no-fire, medium confidence (MC) fire events, and high confidence (HC) fire events is constructed from MODIS-MOD14A2. Nine climate variables from NASA's FLDAS are used as input variables, and 12 dates and 915 study points are considered. Three machine learning ensemble multi-label classifiers, gradient boosting (GBC), random forest (RFC), and extremely randomized tree (ETC), are used for forest fire simulation for the period 2000 to 2021, and ETC is found to be the most accurate classifier. Future fire projection for the near-future period of 2030 to 2050 is carried out with the ETC model, using CMIP6 EC-Earth3-SSP245 General Circulation Model (GCM) data. It is projected that MC forest fire occurrences will decrease, while HC forest fire occurrences will increase, and that the summer months, especially September, will be the most affected by fire.

Assessment of the phenotypic and genotypic diversity of endophytic strains of Bacillus and closely related genera from Carpinus betulus in the Hyrcanian forests of Iran.

Identification and characterization of the endophytic microorganism, is gaining their underestimated significance in influencing health, performance, and other biological attributions of plants in general and forest tree species in particular. Because of the scarcity of information on the endophytic microbiome of the Hyrcanian forests species, including hornbeam (Carpinus betulus L.) trees, as a major constituent thereof, the present study aimed at the identification and partial characterization of the endophytic Bacillus species of Carpinus betulus as the first step in this context. Shoot samples were collected from the Hyrcanian forest locations of Mazandaran and Golestan provinces in Iran. Bacterial strains were isolated from the surface-disinfected shoot segments and subjected to phenotypic characterization. Following assessment of the genetic diversity of the isolates by BOX-PCR fingerprinting, the representative isolates of each of the 15 groups were used for further characterization. Analysis of the nucleotide sequences of the 16S rDNA and HSP60 gene of the isolates led to the identification of 10 species. The predominant species was B. cereus followed by B. subtilis. The other species encountered were B. thuringiensis, Priestia filamentosa, B. velezensis, B. mojavensis, B. amyloliquefaciens, B. safensis, P. aryabhattai, and Gottfriedia acidiceleris. Most isolates possessed characteristics which could contribute to the biocontrol potential of the isolates, including formation of biofilm, production of hydrogen cyanide, tolerant to relatively high concentration of sodium chloride, and antibacterial activity. Ten Bacillus species were identified as the prevailing endophytic species of C. betulus in the Hyrcanian forest of northern Iran, most turned up to possess biological activities involved in biocontrol capability of the isolates against some plant pathogens. These potentially capable bacteria could be implemented in the promotion of plant growth as well as in the biological control of pathogens. This is the first report on the characterization and elucidation of the diversity of the potentially beneficial endophytic species of Bacillus and the closely related genera living in the internal tissues of hornbeam trees.

Fungal decolorization of toxic Triphenylmethane dye by newly isolated Ganoderma fungi: Growth, enzyme activity, kinetics

White-rot fungi have proven their ability to release ligninolytic enzymes for degrading textile dyes. In the present study, ten new strains of the Ganoderma fungi (6001 to 6010) isolated from Hyrcanian forests in Iran were employed to decolorize Malachite Green (MG) as a toxic textile dye. Two isolates, 6009 and 6007, showed the fastest growth and dye decolorization for solid and liquid media, respectively. The strain 6009, identified as Ganoderma resinaceum, completely degraded MG (> 99 %) within two weeks. The results showed that only the laccase enzyme was present in the media, where its activity in the absence and presence of the MG was 2186 and 1787 U/L, respectively. The second-order model was best fitted to the kinetics of the MG dye decolorization. The performance of G. resinaceum in this study showed that this strain could be successfully used for the fungal degradation of MG dye.

Habitat loss of the chestnut-leaved oak (Quercus castaneifolia) in the Hyrcanian forests of Iran: impacts of anthropogenic factors on forest thinning and degradation

Habitat loss of the chestnut-leaved oak (Quercus castaneifolia) in the Hyrcanian forests of Iran: impacts of anthropogenic factors on forest thinning and degradation

Modeling tree species richness patterns and their environmental drivers across Hyrcanian mountain forests

Perception of the way tree species richness distribution varies along the elevational gradient is necessary for applying conservation strategies in favor of biodiversity hotspots. Hyrcanian Mountain Forests of Iran are among the most biodiverse forests in the world and are inscribed in the United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage List. Here, the Bayesian Additive Regression Tree (BART) and Stack-Species Distribution Model (S-SDMs) were used to understand tree diversity patterns of the Hyrcanian Mountain Forests. For all the tree species, we implemented the BART model with nine environmental variables, including six bioclimatic and three topographic variables, to create a habitat suitability map. We used the area under the curve (AUC), True skill statistic (TSS), type I error, and type II error to evaluate the BART model for each tree species. All models were then stacked to estimate tree species richness. Important variables affecting the distribution of tree species in northern Iran were different for each species but, in general, topographic variables such as slope and altitude played a very important role. BART model mapped all the 29 tree species distribution effectively with AUC 0.83–0.98, TSS 0.51–0.92; and low type I and type II errors. A very important point was the high ability of this model to predict species with low presence data. The achievement of this study was identifying the biodiversity hotspots based on the tree distribution pattern along the elevational gradient. We mapped regional richness at 1 km spatial resolution and it was the first effort to predict macroecological patterns in the Hyrcanian forests of Iran. The hotspots were mainly scattered from sea level and areas with 1000 m elevation, which were close to residential areas. In conclusion, these results help forest manager to plan new conservation strategies based on tree richness hotspots.

Combined effects of traffic intensity, skid trail slope, skidder type, and soil moisture content on soil degradation in the Hyrcanian forest of Iran

ABSTRACT Skidding operations affect soil physical properties, which may impact soil sustainability and forest productivity. While the relationship among harvest machine traffic, slope gradients, and increased soil damage has been well-investigated, it is still unclear how soil damage due to repeated passes of different skidder types is interacting with soil moisture and slope conditions. We examined dry bulk density (BD), total porosity (TP), and rutting depth (RD) of skid trail soil in an Iranian temperate forest. The study took into consideration a combination of five different traffic intensities (TI) (1, 4, 8, 12, and 15 passes), two levels of slope gradients (SGs) (≤20% and > 20%), two rubber-tired skidder types (STs) (Timberjack 450C and TAF E655), and two soil moisture contents (SMC) (18% and 31%). Results showed that changes in BD and TP were mainly related to TI regardless of the ST and the skid trail slope. Regardless of TI, SG, and SMC, the TAF E655 skidder caused a higher dry BD increase and soil porosity reduction than the Timberjack 450C. Furthermore, the higher the SMC, the deeper the ruts at all combinations of TI, SG, and ST. Our findings highlighted that ST, SMC, TI, and SG strongly affect rutting and physical properties of soil.

Seasonal variations of triterpene acid contents in Viscum album L. on typical host trees of Hyrcanian forests

Viscum album L. (mistletoe) is a semiparasitic plant of the Santalaceae family. A valuable group of bioactive compounds in mistletoe are triterpene acids (TTAs), which possess anti-inflammatory and anticancer properties. Parrotia persica and Carpinus betulus are the most common hosts of mistletoe in the Hyrcanian forests of Iran. This study was performed to compare the content of oleanolic acid (OA), betulinic acid (BA), and ursolic acid (UA) in the mistletoe foliage (stems and leaves) from P. persica and C. betulus in various seasons for the first time. The results showed that OA was the prevailing TTA in all samples, while UA was found in none of them. The maximum amount of OA (12.38 mg/g dry weight [DW]) and BA (1.68 mg/g DW) was detected in V. album from P. persica in summer. The minimum amount of OA (5.58 mg/g DW) and BA (0.72 mg/g DW) was observed in that growing on C. betulus in winter. However, the mistletoe from C. betulus showed the greatest level of OA in spring (9.06 mg/g DW) and BA in summer and autumn (0.92 and 0.97 mg/g DW, respectively). The data collected in this study complement existing research on this subject from around the world.

Ecophysiological responses of individually and group reared Cydalima perspectalis (Lepidoptera: Crambidae) to alkaloid-containing host plants.

The box tree moth, Cydalima perspectalis (Walker), is an invasive pest of Hyrcanian forests in Iran. In the current study, the effects of two boxwood species, Buxus hyrcana Pojark and B. microphylla Sieb. and Zucc. (Buxales: Buxaceae), were examined on ecophysiology of the pest. The demographic parameters were evaluated based on the age-stage, two-sex life table theory. The physiological characteristics of C. perspectalis were considered through fresh/dry weights and individually/group rearing methods. The results showed that C. perspectalis larvae were able to develop, survive and reproduce on both boxwood species. The developmental times were 41.62 and 41.46 days on B. hyrcana and B. microphylla, respectively. The total lifespan did not differ on boxwood species. However, the difference of fecundity on B. hyrcana (412.82 eggs/female) and B. microphylla (286.06 eggs/female) was significant. The intrinsic rate of increase (r) and finite rate of increase (λ) were significantly higher on B. hyrcana than B. microphylla. The nutritional indices showed that the consumption index (CI) on B. hyrcana were significantly lower than on B. microphylla based on fresh/dry weights in both rearing methods. Conversely, the efficiency of conversion of digested food (ECD) and the efficiency of conversion of ingested food (ECI) on B. hyrcana were significantly higher than on B. microphylla. Despite nonsignificant differences in leaf nutrient contents (except calcium), total protein, triglyceride, and alkaline phosphatase activity were inversely different in larvae compared to adult stage on boxwood species. These findings could help to comprehensively understand the performance of the pest on boxwood species.

Widespread, but less than assumed: Populations of Euphorbia amygdaloides (Euphorbiaceae) from western Asia represent two new cryptic species

The Hyrcanian forests positioned along the southern and south-western shores of the Caspian Sea and the Euxine-Colchic forests along the southern and eastern shores of the Black Sea (western Asia) are renowned as hotspots of biodiversity and represent major refugia of Eurasian Tertiary relict forest species. One of them was considered to be Euphorbia amygdaloides (Euphorbia sect. Patellares), a forest species with wide distribution from northern Africa across Europe to western Asia. Using nuclear ribosomal ITS and plastid ndhF–trnL sequences we here show that the western Asian populations previously treated as E. amygdaloides are clearly divergent from European E. amygdaloides and actually pertain to two new species, which are also morphologically different. The newly described E. sylvicola is widespread in the Hyrcanian and Euxine-Colchic forests and is morphologically most similar to E. amygdaloides, with which it also shares its genome size. On the other hand, E. caspica is endemic to the Hyrcanian forests in Iran and is most closely related to another western Asian species, E. macroceras, with which it partly overlaps in distribution. Both species have also similar genome size, slightly lower from that of E. amygdaloides and E. sylvicola, but morphologically E. caspica resembles more E. amygdaloides than E. macroceras. Our study uncovered cryptic diversity in the forests of western Asia that had remained hidden due to slow rates of morphological evolution, i.e. morphological stasis, commonly observed in other Tertiary forest relict species, and highlights the Euxine-Colchic and especially the Hyrcanian forests as important centres of biodiversity and endemism.

Challenges Facing the Improvement of Forest Management in the Hyrcanian Forests of Iran

We address two main challenges facing the implementation of sustainable forest management (SFM) in the Hyrcanian forest of Iran: inconsistent forest policy and the use of outdated science and techniques. We propose the Sustainable Hyrcanian Forest Management Model (SHFMM) as the best currently available solution to achieve improved management of the northern forests of Iran. The management of the Hyrcanian forests suffers from a lack of scientific knowledge and state-of-the-art technologies. There is a pronounced difference in the mindsets of older and new-school forestry scholars regarding how to approach these deficiencies: the old-school mentality prefers conventional forestry despite its limitations, whereas more recently trained scholars believe that the adoption of 21st-century technological advances would lead to improved management. The lack of trust between policymakers and local communities is another significant challenge and has resulted in conflicts over management practices in the Hyrcanian forests. We suggest that the Hyrcanian Sustainable Forest management model (SHFMM) would provide a hierarchical framework for making decisions. Using this model, each sector—whether state or private—is empowered to make decisions. Further, it encourages all sectors to work together in its holistic implementation. The SHFMM is based on the outcomes of several independent studies of forest management in the Hyrcanian forest. Despite its site specificity, many lessons learned during its development could be applied elsewhere.

Elevational shift of endangered European yew under climate change in Hyrcanian mountain forests: Rethinking conservation-restoration strategies and management

Prioritizing new areas for conservation in the Hyrcanian mountain forests is important because future climate change is an immediate threat to endangered species in these areas. Taxus baccata L. (European yew) is one of the most important coniferous species of the Hyrcanian forests that is endangered today for various reasons; therefore, the conservation and restoration of this valuable species is essential. The present study was conducted in order to identify areas with high potential for restoration and conservation of yew with consideration of future climate change. Maximum Entropy (MaxEnt) was used to model the current and future distribution of yew in Hyrcanian forests of northern Iran. VIKOR fuzzy model applied to prioritize conservation and restoration areas. The results showed that MaxEnt model has high efficiency in modeling the distribution of yew with area under curve (AUC) = 0.98 in the study area. Importance analysis of explanatory variables showed that distance from rivers, geology, slope, precipitation of warmest quarter (bio18), and annual precipitation (bio12) were more important than other variables in the potential distribution of yew. The results showed that at current condition, suitable areas for yew in the Hyrcanian forests of Iran are distributed along an elevation gradient from sea level to 2600 m, and under the future climate change (2050 and 2070) this species will shift to higher elevations and lose the lower elevation habitats. The findings of this study predict that the desired habitats of yew in Hyrcanian forests will be severely affected by climate change. Given these cases, it is necessary to make management and conservation decisions in relation to this species, taking into account the effects of climate change and adaptation in the Hyrcanian forests.

A preliminary checklist of saproxylic beetles (Coleoptera) in the Hyrcanian forests of Iran, with distributional data

Saproxylic beetles play a vital role in conservation as indicators of the status of unmanaged forests. In light of the concern regarding the adverse impact of anthropogenic pressure on biodiversity, an essential step in forest conserva-tion strategy is the identification of saproxylic beetles. The Hyrcanian forests are a unique remnant of natural broadleaf temperate forests, with an evolutionary history that can be traced to the Tertiary and a high diversity tree species. Here we present the first checklist of saproxylic beetles in the Hyrcanian forests, including 398 species of saproxylic beetles, belonging to 207 genera and 46 families, identified by us. Based on our results and literature data, at least 670 saproxylic beetles occur in the Hyrcanian forests. The bias in our results towards some families supports the view that the detection of additional species can be expected, particularly from the forests with a greater diversity of tree species.

Effects of plot size on assessment of tree species diversity in Caspian forests of Iran

Abstract. Mirzazadeh A, Pourbabaei H, Daryaei MG, Bonyad A. 2022. Effects of plot size on assessment of tree species diversity in Caspian forests of Iran. Biodiversitas 23: 4879-4886. Tree species diversity is important to forest managers because any management that reduces tree species diversity may greatly reduce commercial benefits. Therefore, control over tree species diversity is an important aspect of hardwood forest management. An efficient and quick survey method is needed to facilitate the assessment of tree species diversity in forest stands. In this study, the effects of plot size on the assessment of tree species diversity were compared in the uneven-aged hardwood stands in the Hyrcanian forests of Iran. There were selected 50 hectares of these forests representing the regional forests. Sampling procedures were carried out on concentric lozenge plots with different sizes, including 400, 800, 1000, 1200, 1600, 2000, 2500, and 5000 m2 in the dimensions of 150×150m. For each plot, the type of the species and the number of trees were recorded. Shannon-Wiener (H’), Simpson (1-D), Mc-Arthur (N1), Hill (N2), Camargo (E'), Simpson (E1/D), Nee (EQ), Smith-Wilson (Evar), Menhinick (R2), Margalef (R1) indices were used to estimate of tree species biodiversity. The precision and cost criteria (E%2× T) were applied for a better evaluation of different plot sizes. The obtained inventory error values showed that Hill (diversity), Camargo (evenness) and Menhinick (richness) indices had the lowest inventory error in the different plot sizes. Also, the lowest value of inventory error in diversity, evenness and richness indices were related to plot sizes of 2500, 5000, and 5000 m2, respectively. Based on the obtained results of diversity and evenness indices, there was a significant difference between the different plot sizes and different indices. The results showed that the lowest value of E%2×T for diversity, evenness and richness was related to Hill (800 m2), Camargo (1000 m2), and Menhinick (400 m2). The finding results revealed that plot size had a significant effect on tree species’ evenness.

New records of Empididae and Hybotidae (Insecta: Diptera) from Hyrcanian forest in Iran and Azerbaijan

The genus Dolichocephala Macquart, 1823 of the family Empididae is recorded for the first time from Iran and Azerbaijan, including one species D. monae Joost, 1981. A neighbour-joining tree based on genetic divergences on the CO1 gene within nine species of Dolichocephala is provided. In addition, the genus Oropezella Collin, 1926 of the family Hybotidae (one species O. sphenoptera (Loew, 1873)) and two species of the subgenus Empis s. str. of the genus Empis Linnaeus, 1758 (E. (E.) earina Collin, 1960 and E. (E.) temryukiensis Kustov et Shamshev, 2013) of the family Empididae are reported for the first time from the territory of Iran. The female of E. (E.) temryukiensis is described for the first time.

Susceptibility of Cydalima perspectalis (Lepidoptera: Crambidae) larvae to some reduced-risk insecticides in laboratory bioassays

Box tree moth (BTM) Cydalima perspectalis (Walker, 1859) is the most harmful pest of different boxwood species in Europe and Asia including Caspian boxwood Buxus hyrcana in the Hyrcanian forests of Iran. Accessible and effective eco-friendly insecticides are required for the pest control. Thus, susceptibility of 2<sup>nd</sup> and 4<sup>th</sup> instar larvae of BTM to commercial formulation of Bacillus thuringiensis (Bt), two plant extract formulations, Bio1<sup>®</sup> and Matrine<sup>®</sup>, and three insect growth regulator (IGR) insecticides, chlorfluazuron, chromafenozide and diflubenzuron were investigated in laboratory bioassay. Except for diflubenzuron, significant mortality of both instar larvae was observed. At the endpoint of the experiments (96 h), 75.2–90% of second and 80–85% of fourth instar larvae had already died, as a result of feeding on leaves treated with the highest concentration of the insecticides. Furthermore, based on Probit analysis, Matrine<sup>®</sup> exhibited the highest efficiency (lethal concentration LC<sub>50</sub> = 2.87 μL·L<sup>–1</sup>) on 2<sup>nd</sup> instar larvae and followed by Bio1<sup>®</sup> (8.07 μL·L<sup>–1</sup>), chlorfluazuron (173.3 μL·L<sup>–1</sup>) and Bt (326.3 mg·L<sup>–1</sup>). The LC<sub>50</sub> of Matrine<sup>®</sup> and Bt for 4<sup>th</sup> instar larvae were 1.75 μL·L<sup>–1</sup> and 335.8 mg·L<sup>–1</sup>, respectively. Our study revealed that Matrine<sup>®</sup> and chromafenozide could be alternatively used against BTM in situations where there is a permission and need to use insecticides.

Viscotoxin and lectin content in foliage and fruit of Viscum album L. on the main host trees of Hyrcanian forests

Mistletoe (Viscum album L.) is a hemiparasitic plant that absorbs water and nutrients from the host tree. Mistletoe contains two groups of cytotoxic, immunomodulatory and antitumor proteins, viscotoxins and lectins. This study evaluated the quantity and quality of viscotoxins and total lectins in the stems with leaves (foliage) and fruit of mistletoe on Parrotia persica and Carpinus betulus in September with immature green berries and in December with mature white berries. Viscum album L. plants were harvested from host species located in the Hyrcanian forests of Iran in 2019. The highest level of viscotoxins was detected in the December foliage of V. album settled on C. betulus (9.25 mg/g dry weight [DW]), and the highest content of lectins was found in the December foliage of V. album settled on P. persica (0.79 mg/g DW) and C. betulus (0.73 mg/g DW) respectively. The immature green berries of V. album from both host species contained much higher concentrations of viscotoxins and lectins than the mature white berries. Four isoforms of viscotoxins, viscotoxin A1, A2, A3 and B could be identified in all samples of both host species. Viscotoxin A3 was the predominant viscotoxin isoform followed by viscotoxin A1.

Projection Matrix Models: A Suitable Approach for Predicting Sustainable Growth in Uneven-Aged and Mixed Hyrcanian Forests

The Hyrcanian forests of Iran are mainly managed with the single-selection silvicultural technique. Despite significant ecological benefits associated with selection cutting, this type of forest management leads towards more challenging situations where it is difficult to maintain and practice successful forestry than in even-aged systems. Therefore, this study provides relevant management tools in the form of models to estimate low growth levels in Hyrcanian forests. In the present study, estimation of the population growth rate and then the allowable cut rate of these forests using a matrix model have been calculated in the Gorazbon district. For this purpose, the data of 256 permanent sample plots measured during the years between 2003 and 2012, as well as the data recorded about the trees harvested according to the forestry plan, have been used. As a first step, the most frequently occurring tree species were divided into four groups (beech, hornbeam, chestnut-leaved oak, and other species). Compartments of the district were divided into two groups of logged and unlogged compartments. The purpose of this division was to estimate the allowable cut and compare its volume with the volumes of observed and predicted allowable cuts obtained from forestry plans. The results showed that the total operated allowable cut (OAC) in logged compartments was more than the estimated allowable cut (EAC). In unlogged compartments, the total predicted allowable cut (PAC) was more than EAC. A comparison of EAC and OAC showed that hornbeam has been harvested more than its potential. However, chestnut-leaved oak and other species group have depicted opposite trends. Our models provide important advancements for estimating allowable cut that can enhance the goal of practicing sustainable forestry.

Cut slope stability assessment along forest roads using the limit equilibrium approaches and Slide software

Calculating the factor of safety (FS) as slope stability factor is necessary to prevent environmental damage. Therefore, this paper aims to (i) calculate FS using the limit equilibrium approaches and Slide software and (ii) investigate the stability of slopes according to calculated FS (Janbu and Bishop methods) and status of different sites in the study area (Hyrcanian forest of Iran). Six landslides were selected along the forest road by a field survey. Landslide dimensions including length, width, and height were measured using meters. Slope gradients were measured using the Suunto clinometer. The Slide software was used to evaluate the stability analysis of slopes. According to laboratory tests on soil samples the average of the liquid limit was recorded as 58%. The results of the direct shear test showed that the rate of soil cohesion (c) and coefficient of friction angle (φ) decreased with an increase in moisture content. According to the results, the factors of safety for landslide sites (Sites 1–6) were calculated to be 1.3, 0.65, 0.76, 0.55, 1.19 and 1.51, respectively. These calculated FS can accurately determine the slope status in terms of slope stability. According to the software classification, the status of Site 1 is “susceptible to landside”. Sites 2, 3 and 4 are “very high risk”. Also, the status of Sites 5 and 6 are “high risk” and “stable”, respectively. The instability of the slopes in studied sites is related to the drainage system (lack of culverts or ditches) as well as marlstone as bedrock. According to the calculated FS in different sites and comparison of the obtained results with the real conditions of sites, it can be concluded that the slope stability analysis in the Slide software is very accurate and it can be used to determine the factor of safety under different conditions in terms of morphology, hydrology and soil mechanics.

Multiple streams framework and logging policy change in the Hyrcanian forests of Iran

ABSTRACT The 2017 logging ban in Iran’s Hyrcanian forests represents a considerable forest policy change, which was proposed following the development of other major policies to improve natural resource management. The aim of this paper is to explain the development of the logging ban policy using Kingdon’s multiple streams framework (MSF). Qualitative methods – interviewing and document review – were used for data collection and analysis. The problem, politics and policy streams are shown to be linked in framing the policy change. We investigate how participants in the development of the policy used interlinkages between the problem, politics and policy streams to develop their proposals and how this simplified the change process. Despite some limitations, the MSF is helpful in explaining and analysing outcomes of natural resource management policy development processes.