مجله پژوهش و توسعه جنگل
سال پنجم شماره 2 (تابستان 1398)

Apple (Malus orientalis) has been distributed throughout the Hyrcanian forest from lowland regions to steep and mountainous areas. For evaluation of genetic diversity, leaf materials were collected from 60 individuals of 6 populations. DNA was extracted and studied by six SSR primers: (GD142), (GD12), (GD147), (GD96), (GD100) and (GD162). The results showed that 45 alleles with 0.39 heterozygosity were detected for six primers. The mean of heterozygosity was 0.39 and the lowest (0) and highest amount (1) were observed for (GD100) in “Afratakhte”, “kodir”, “Sourdar”, “Yoush bala”, “Yoush paein” population and for GD162 in “kodir”, “asalem”, “yoush miani” and “yoush paein” populations, respectively. The maximum Nei genetic distance was belonged to “asalem” and “sourdar” populations and the minimum was related to “Yoush bala” and “asalem”. The result of AMOVA indicated that the intra and inter population diversity were 97% and 3%, respectively that indicated significant diversity within population of this species. Because of different habitat conditions and long geographical distance among populations, The low genetic differentiation and similar heterozygosity within populations show high gene flow among populations of Malus orientalis in north of Iran.

The aim of this study was to study effect of fire on vegetation and natural regeneration in Shanderman forests, Guilan province 7 years after burning. For this purpose, two burned and unburned areas were selected. Within each of the study areas, we used a random systematic 150 m × 150 m sampling grid to locate 40 circular plots of 1000 m2 for tree and shrub species (20 plots in burned area and 20 plot in control area). In each plot, density and DBH of tree species and density of shrub species were measured. Regeneration density was studied by 100m2 plots. Regeneration was studied in three classes as height < 1.3 m, DBH < 2.5 cm, and 2.5 cm < DBH < 7.5 cm. The results showed that density, the DBH and basal area of tree species and density of shrub species significantly deceased after burning. Also, density of regeneration significantly increased after burning. In tree layer, density of Quercus castaneifolia, Carpinus betulus, Zelkova carpinifolia and Parrotia persica significantly increased after burning. In shrub layer, density of Prunus divaricate, Mespilus germanica, Crataegus microphylla and Ruscus hyrcanus significantly decreased after burning. Forest structure was uneven-aged with a reverse J distribution in each two areas. Composition and pattern of dominance didn’t changed in tree, shrub and regeneration layers.

This research was performed in order to survey quantitative characteristics of Pistacia atlantica trees on gum production in the forests of Chaharmahal & Bakhtiari Province. At the first step, two elevation classes (1200-1600 m and 1600-2000 m) were choosen and trees selected in different DBH classes. Biometric characteristics of wild pistachio trees such as DBH, crown diameter, total height and bole height were used to assess the impact of gum production on wild pistachio trees. The gum was extracted from selected trees separately and weighted. The results showed that the mean of gum production is 571.9 g in each pistachio tree. Also, significant difference at 5% level between the factors of DBH and total height and at 1% level between crowns diameters were seen. The tree gender also showed a significant effect on the amount of gum production, so that the average production of gum in male and female trees were 608.1 and 354.8 g respectively. The results showed that there is no significant difference between amounts of gum production in different bole height.

By paying little attention to the process of organizational growth, the reason of the fall and end of the life-cycle of most organizations, non-update knowledge and data and lack of consistency with the world’s recent condition and on the other side, employees resistance against the change, carelessness of organization's Senior Managers about human capabilities for acquisition and application of up-to-date knowledge and exit of huge part of valuable and practical organizational knowledge because of experienced employee retirement, can be realized. This research aimed for studying factors influencing knowledge management of West Azerbaijan Province Natural Resources Administration. This research has been done in a survey and descriptive-analytical method using random sampling. 74 questionnaires based on The APO model (Its validity was proved by other studies) with Likert's five-option spectrum, were distributed and Reliability Analysis test and Cronbach's alpha statistic were used to determine reliability of the questionnaire. Data like: Information Technology infrastructure, funds, education and learning and innovation, key work processes, knowledge sharing incentives, organizational training, career development programs and etc, were asked by the questionnaire. The statistical population of this research includes employees of West Azerbaijan Province Natural Resources Administration. To determine the contribution of factors affecting knowledge management, multiple linear regression (stepwise) and SPSS23 software were used. Results showed that “employees” and “learning and innovation” are factors affecting knowledge management results and employees have positive and significant effect on learning and innovation. Also, from the point of view of knowledge management maturity, West Azerbaijan Province Natural Resources Administration is in the development phase.

Improvement of the irrigation water efficiency through irrigation management is one of the most effective ways to save water use in the agriculture. The experiment was conducted to evaluation of different irrigation levels on various indicators of growth in ash in 2016 and 2017. The experiment treatments were included irrigation (50, 75, 100 and 125% water requirements) as main factor and time as sub factor that was accomplished in a split plot replicated in time at randomized complete block design with four replications. Irrigation was done with estimated value of irrigation water requirements using FAO equation and WUCOILSIII method. The results showed that in both years irrigation with 50% of plant water requirements resulted in significant decrease in height, shoot length, crown diameter, leaf abundance, succulence and leaf area index in comparison with the control treatment. Results indicated that water demand varied from 50% to 100% basic water requirement due to the growing season (based on time and growth stage of the seedling) and air temperature. Generally, by examining the growth index and succulence of plants under irrigation and considering effective rainfall and irrigation efficiency, irrigation at 75% of basic water requirement in studied field was recommendable as optimal irrigation.

This research aimed to investigate carbon sequestration and biomass of Acer monspessulanum stands in Ghale Gol region. For this purpose, 30 Acer monspessulanum trees were selected using random sampling method, and quantitative characteristics including big and small crown diameters, tree height, crown height and DBH of them were measured and recorded. Then, of all geographical aspect 5 leaves at a height of 1.5 meters of crown tree were collected. At first wet weight of leaves were measured, then dried leaves were weighted again. Amount of carbon was obtained after burning leaves and weighing ash of dry leaves. Also, amount of carbon dioxide absorbed by the leaves after applying 3/67 in the amount of organic carbon stored in the leaves was estimated. The results showed that biomass average, carbon sequestration and the average amount of carbon dioxide absorbtion, were measured 8.17, 8.57 and 31.45 kg per ha respectively, and the leaf area was estimated 0/868 m2 / ha. Probability level, there is a significant difference between the average of carbon sequestration and biomass, in four geography tree crown aspects. However, at 95% probability level there isn’t significant difference between the average leaf areas, at four geography aspect. Amount of leaf biomass in the east aspect and amount of carbon sequestration in the western aspect were higher than other aspects.

This research was carried out with the aim of investigating the effect of mass density on woody and herb diversity in oak stands in Sardasht forests of West Azerbaijan province. For this purpose, the effect of density on the diversity and richness of tree and grass cover in three populations with Sparse, Completely sparse and relatively dense populated densities was investigated. 30 square plots were arranged in a randomized manner in the forests of the region, The distance between the sample units was 100 meters and the distance between the transects was 200 meters. Types and characteristics of tree species and shrubs were recorded in each sample. The frequency and species of herbaceous species were recorded in 5 micro particles with a dimension of 1.5 × 1.5 m in each sample. The correlation between stand density, richness and diversity indices of herbaceous species and tree species diversity was investigated by Pearson method. Tokay test was used to compare the mean of richness and species diversity between thinness, thinness and fairly massive densities. The results showed that 117 species of plants (5 tree species and 112 grass species) are present in the region. Correlation between grassland characteristics and tree specification showed that the Shannon uniformity index is correlated with the number of spikes, mean diameter and cross-section, and the Simpson species diversity and Margalof species richness with the average diameter and cross-sectional area is correlated. Also there was no significant difference between the diversity and richness of herbaceous and tree species in different densities.

Destruction of forest areas to meet the fuel needs of forest dwellers has caused irreparable damage to these resources. The use of new energy, especially the use of solar energy, is an effective solution for replacing fuel wood in the country's forest villages. One of the tools used to heat water through solar energy is solar water heaters that their use are increasing day by day. In this research, the effect of using solar water heaters on reducing the dependence of forest households of Lordegan Township in Chaharmahal-o- Bakhtiari province has been studied and analyzed. A total of 40 households using solar water heater for three years were surveyed in the three villages of Lahderaz, Lirabi and Sarpoot in the central part of Lordegan city. According to the results of this study, before the installation of solar water heaters, the average annual consumption of wood for heating water was 19.17 cubic meter per household, which was reduced to 2.72 cubic meters after installation of the water heater. This 86% reduction in fuelwood consumption is indicative of the success of the solar water heater project.

In this study, firstly, the process of changes in land coverage/usage was determined through satellite image analysis in the Dohezar and Sehezar forested landscape in Tonekabon County, Mazandaran Province during the years of 1984-2016 .Then, impacts of changes in land coverage/usage on the quantity of carbon sequestration and storage were mapped, quantified and valued using InVEST carbon model within the same time period. The result showed that dense and low-dense forest cover have been decreased by 18 and 55 percent, respectively during three decades, while semi-dense forest has been increased by 63 percent. It was also found that the effects of these structural changes in forest cover have reduced carbon sequestration capacity by 1927474 tons. This reduction has caused a loss of 53,137,258.80 US $ (equivalent to 568,568,699,160 billion rials) over three decades.

Until now, many pests associated with the common ash and its outbreaks from Europe have been reported including the ash sawfly, Tomostethus (Blennocampinae). The present study was carried out in spring of 2017 following the severe outbreak of the ash sawfly in West Azarbayjan, north Zagros forests. The collected specimens were identified using molecular methods and sequencing of a partial COI. The Blast results showed a sequence of the present study is related to the genus Tomostethus and the species, T. nigritus with 92 percent similarity. The ash sawfly is dispersed as calmly on the margin of the Zab River in West Azarbayjan province. The current primary study on the existence and prevalence of this pest in northern Zagros should be considered seriously and details of the aspects of intense control and monitoring should be determined for the management of the invading pest in the attention of forestry conservation officials.

In addition to investigate effects of physiography factors including of slope (3 classes), aspect (4 classes), height above sea level (3 classes) on decline of oak trees, the aim of this study was decline modelling of Quercus brantii under effects of physiographic factors in Dalab forests of Ilam province. For this purpose, 509 hectares of Dalab forests of Ilam province were selected. Based on systematic-random sampling method with 200 × 250m dimensions, 100 circular plots (2000 m2) were measured. In each sample, physiography factors and percentage of decline were measured. ANOVA and Duncan tests were used to compare of oak decline in different physiography factors. Logistic regression model was used for modelling of oak decline. Omnibus test, log-likelihood and pseudo r-square coefficients were used to evaluate the logistic regression model. The results of ANOVA test showed that physiography factors had a significant effects on the oak decline. Also the results showed that with increasing slope and altitude, decline of oak trees was increased. The results showed that the lowest and highest of tree decline were belong to east and south aspects respectively. The results of this study can conserved areas that have oak decline, to be effective.