مجله پژوهش و توسعه جنگل
سال نهم شماره 1 (بهار 1402)

The quantitative status and probability distribution functions of crown classes of Brant's oak (Quercus brantii) stands were investigated in the Qala Gol region of Khoramabad city in this study. The number of two classes of degraded and less degraded forest was selected for this purpose by identifying the forest and obtaining samples in a selective manner, and then a square sample plot of one hectare with dimensions of 100×100 meters was planted in each class. The crown diameters of 72 coppice trees of Brant's oak in the less degraded region and 52 coppice trees of Brant's oak in the degraded area were measured. In this study, statistical distribution models such as Weibull, Gamma, Normal, Log-Normal, Beta, and Johnson Sb were utilized, and the Anderson-Darling test was used to determine the goodness of fit. The results indicated that the canopy percentage in the degraded region (11.9%) is lower than the canopy percentage in the less degraded area (37%), and the average canopy area in the less degraded stand (51.46 m2) is considerably greater (P≤ 0.01) than the canopy area in the degraded stand (22.89m2).  Based on the goodness of fit test results in the less degraded stand, the Johnson SB, Weibull, Gamma, and Beta functions were proposed as the best fit functions for the canopy classes in the degraded region, respectively. The current study demonstrates that the rate of degradation has a significant influence on the probability distribution functions of tree crown cover in coppice Brant's oak stands in the Zagros forests.

The absence or lack of improved seeds with high genetic variety has long been one of the most major obstacles to forest regeneration and growth. In addition to supplying replicable seeds and excellent seedlings, seed orchard creation is critical in providing enough genetic variety for future research. In a forest covering around 100,000 hectares, 18 maternal trees were discovered in three groups. The DNA was extracted using a modified CTAB technique, and the polymerase chain reaction was carried out with SSR markers. The allelic features of amplified markers, as well as genetic indices, were determined using GenALEx software, and the similarity matrix of Jaccard coefficients, as well as the clustering of 18 chosen trees, were performed using the UPGMA technique and NTSYS software. Fragment amplification was done in 10 SSR markers based on the findings of vertical electrophoresis of PCR products from 15 pairs of SSR markers. In all, 57 polymorphism alleles were discovered in 18 chosen ash for 10 SSR markers, with the FE3 marker having the most (ten polymorphic alleles) and the FE5 marker having the fewest (two polymorphic alleles). Each SSR marker had an average of 5.7 polymorphic alleles. The clustering of 18 distinct trees using the UPGMA algorithm revealed that the chosen trees were divided into three major clades. The P1, P2, P3, P4, P8, P9, P10, P15, P17, and ultimately P18 plants can be utilized to build a seed orchard based on the results.

The goal of this descriptive-survey study is to examine the situation and categorize the level of livelihood resilience of agroforestry system users in Paveh city in the face of drought. The statistical population of agricultural grove system stakeholders in Paveh city was 270 persons, of whom 156 were chosen using the stratified sampling method. A questionnaire created by the researcher was used to collect information. The data was coded in SPSS software and examined in four dimensions of vulnerability, learning capacity, self-organization, and diversity utilizing human, social, financial, physical, and natural capital. Finally, this community was shown to be more resilient than normal. The Kruskal-Wallis test was performed to assess the difference in average resilience among plantation grove subsystems. The results revealed that the gardener-pasture-farmer subsystem had a greater average resilience than the other two subsystems. The findings of this study may be of interest to the Agricultural Jihad Organization and the Environmental Organization in order to promote agroforestry systems and develop the components influencing resilience levels in order to support sustainability and boost livelihood resilience.

The goal of this study is to see how well the forest canopy density (FCD) model and the GLAMA mobile ‎app estimate the canopy cover density of Zagros forests in Sardasht province. Landsat 9 Operational Land ‎Imager-2 (OLI-2) in 2022 was employed for this purpose. Four indices were created to run the model: 1- Advanced ‎Vegetation Index, 2- Bare Soil Index, 3- Shadow Index, and 4- Thermal Index. The Scaled Shadow Index and Vegetation Density index were then computed by integrating and synthesizing indices one and two, as well as indices three and four, and the FCD model map was created by combining these two indices. The created model was validated using GLAMA mobile app and ‎hemispherical photographs. For this purpose, 100 square sample plots in Sardasht city with varying canopy ‎cover were chosen, and photographs of the canopy cover were taken at five positions on each sample ‎plot. The overall accuracy of the FCD model generated for Sardasht Province was 76%, with a Kappa ‎coefficient of 0.697. Furthermore, the correlation results demonstrate a strong (R2‎ = 0.985) and significant ‎‎(p-value = <0.0001) correlation between the average canopy cover index values estimated by ‎hemispherical photography using GLAMA software and the values acquired by the FCD model. According ‎to the findings of this study, the FCD model developed using Landsat 9 satellite data and the GLAMA ‎mobile app performs very well in estimating forest land canopy density in Zagros forests.

Myzocallis coryli (Goetze) (Hemiptera: Aphididae) is a major hazelnut pest in Iran. This aphid attacks the stems and leaves of Corylus avellana L. hazelnut trees, and as the population grows, it causes the leaves of hazelnut trees to dry and fall, reducing the quality of the nuts. The use of entomopathogenic fungi in the management of hazelnut aphid has been prioritized in order to reduce negative environmental consequences. The isolates IRAN 715C, DEMI001, M14, and V245 from the fungus Metarhizium anisopliae were employed in this work to assess on the adults of M. coryli. To assess the toxicity of four isolates, the Probit tool in SPSS 21 software was employed with a fatal dose of 50% of the LC50. The LC50 values for DEMI001, IRAN715C, M14, and V245 isolates on adults of M. coryli in laboratory and field settings were 1.9×106, 2.34×106, 0.469×106, 1.79×106 and 7150×106, 101000×106, 4860×106, 14700×106 con/ml, respectively. According to the findings of this investigation, isolated M14 is particularly efficient on adult filbert aphids. In addition, a larger concentration of fungal suspensions is required in the field to suppress adult aphids than in the laboratory. The additive or synergistic effects were not seen when assessing the interaction between two effective isolates. As a result, the use of isolate M14 in the hazelnut aphid integrated management program (IPM) is suggested.

The variations in the number of six parameters of the landscape metrics in Arasbaran forests were explored in this study. Landsat 8 images from August 2015 were utilized for this purpose. For both protected and non-protected regions, forest and non-forest land use maps (kappa coefficient 0.9) were created, and necessary values were estimated using this map. According to the results, forest covers 34.98% of the protected area and 48.33% of the non-protected area, based on the index of the ratio of the area of the forest class to the surface of the land. In terms of the index of the larger patch of forest class, it was discovered that the largest patch of forest covers 22.0207% of the land in the protected region, while 41.3870% of the area in the unprotected area. In addition, the value of the index of the average area of a patch of the forest class in the non-protected area (8.4947 hectares) is more than twice that of the protected area (18.2241 hectares), and the value of both indicators patch density and edge density in the protected area is higher than in the non-protected area. According to the findings, the presence of processes of forest surface fragmentation is more visible in the protected area than in the non-protected region.

Prosopis cineraria Druce (L.) was utilized in this study to assess the environmental contamination in Bandar Abbas. The experimental community encompasses the ecosystems of Dasht Tazian, Bird Garden in the east of Bandar Abbas, Tal Siah and Gachin villages in the west of Bandar Abbas, and the industrial region in order to achieve this strategy. Twenty P. cineraria shrubs were chosen from each community. Heavy metals Zn, Pb, Cd, Mn, and Ni were tested in leaf samples, substrate soil, and industrial dust deposited on leaves. Following the determination of metal concentrations in the samples, the Igeo, CF, MAI, BCF, PLI, and mPELq indices were used to assess the extent of contamination and the ability of P. cineraria shrubs to accumulate metals. The concentrations of Zn, Pb, and Cd in leaves, soil, and industrial dust were found to be greater than the norm. Metal concentrations were higher in the substrate soil samples. The biggest level of heavy metal pollution was found in Tal Siah village, Getchin, Dasht Tazian, and Bird Garden, which are the least and most remote from the industries west of Bandar Abbas. According to the Igeo and CF index, nickel and manganese are unpolluted, however cadmium is a major polluter of ecosystems. The PLI index indicates that Bandar Abbas' ecosystems are contaminated. According to the bioaccumulation index (BCF), mesquite shrubs are intermediate pollution accumulators. The pollutant transfer coefficient from soil to plant in Bandar Abbas habitats ranges between 0.23 and 0.65. It may be inferred that the lands around the factories in Bandar Abbas' west are extremely polluted, but Iranian mesquite shrubs have the potential to accumulate and eliminate industrial pollutants from Bandar Abbas' natural ecosystems and can be employed as a plant technique. Treatment should be applied to safeguard the environment.

In this study, the structure of Zagros forest stands was analyzed using neighborhood-based indices such as Clark and Evans, uniform angle, mingling, diversity of dimensions, diversity of combined structure, and distance to the nearest neighbor in two one-hectare (unprotected) sample plots in Chaharzebar and Barzeh forest areas (as a sample of the majority of Kermanshah province's forests). Clark and Evans index values of 0.87 and 0.88 for quadrupeds and ridges, respectively, and uniform angles of 0.51 and 0.5, respectively, revealed a spatial distribution pattern in both hilly areas and a species distribution pattern in random quadrants and the Barzeh region. The average mingling index values of 0.13 and 0.005 revealed that the Barzeh region had substantially lower species mixing than the Chaharzebar region. In addition, the mean diameters of differentiation indices with values of 0.55 and 0.38, and height differentiation with values of 0.2 and 0.19, were determined for Chaharzebar and Barzeh, respectively, indicating a minor height difference and the diametric superiority of Chaharzebar trees over Barzeh. In general, the structure of the forest in the analyzed regions has been significantly altered, and the findings of the hybrid diversity index revealed a low level of biological, species, and dimensional variety in the two studied forest stands.

This study was carried out to determine the effects of the entomopathogenic fungus, Beauveria bassiana (Bals. Criv.) Vuill, on survival and population growth parameters of the Myzocallis coryli Goetze one of important pest of hazelnut. Effect of LC30 on development, reproduction and life table parameters of the Filbert aphid were studied under laboratory conditions. The LC50 values of IRAN429 and Z-1 isolates were 9.86×104 and 1.03×106 conidia ml-1. The fungal treatment significantly (P<0.005) reduced nymphal period, life span and fecundity of the aphid in comparison with control. The rm values of IRAN429 and Z-1 in LC30 were 0.15 and 0.16 female/female/day respectively which was significantly reduced in comparison with control aphid (0.18 female/female/day). The lifelong of IRAN429 (31.75 day) and Z-1 (39.45 day) treatments were had significant difference with control (43.50 day). The fecundity value of IRAN429, Z-1 and control were 31.75, 39.45 and 78.41 (nymph/ female) that have significant difference with each other. Finite rate of increase (λ) was significantly reduced in treated aphids (IRAN429= 1.17 and Z-1=1.17 female/female/day) compared to control (1.19 female/female/day) treatment. The results of the present study showed that due to the significant effect of pathogenic fungi in sub-lethal concentration on the survival and reproduction indicators of aphids, it can be used in the integrated and biological management program of target pests.