مجله جنگل ایران
سال هفتم شماره 2 (تابستان 1394)

In country development، the cooperative system is considered as an efficient tool for providing the ground of people participation. For this reason، cooperative forestry in maintaining and restoring forest areas may ultimately be important for rural development. The purpose of this research was to study the impact of forestry cooperatives on forest rural development in Golestan province. The study population consisted of 428 regular members and the board of forestry cooperatives in Golestan province which 156 of them were selected using classified random sampling. A questionnaire was used for data collection. Validity of the questionnaire was confirmed by expert’s insights and its reliability was assessed by calculating Cronbach''s alpha coefficient for the rate of participation of the cooperatives’ members (α=0. 712) and the cooperatives’ impact on rural development (α=0. 783). Results indicated that members'' participation in cooperatives’ affairs varies from too low to medium. Also، the impact of forestry cooperatives on rural development can be assessed as low. However، the relationship between the members’ participation in the cooperatives and the effect of cooperatives on rural development is strong and positive. The results of path analysis showed that among aspects of the members'' participation in forestry cooperatives، participation in benefit sharing has the greatest effect on rural development. But in terms of the total direct and indirect effects of variables، participation in implementation has had the greatest impact on rural development. Using participation of members of cooperatives in all forestry cooperatives’ affairs and more effort to increase the income of cooperatives’ members are the suggestions of present study.

The North forests of Iran play a major role in carbon storage through above-ground biomass، and they are of extreme significance in terms of biodiversity. Therefore، the present study was accomplished in order to specify the relationship between species diversity changes and above-ground biomass in the mixed-beech forests in Sari region، Mazandaran Province، Iran. In order to determine the amount of above-ground biomass، some discs of 2 cm thickness were sampled in return for each felled tree at 2-5 m. The samples were put in the oven for 24 hours (105°C) in order to determine their dry density. In order to determine the tree biomass (volume multiplied by dry wood density) and plant diversity (Shannon- Wiener''s diversity، richness and evenness indices)، a network with grid dimensions of 80 × 100 m was laid on the topographic map and totally 50 400 m2 sampling plots were established in the study area in an area about 46. 4 hectare. For collecting data related to herbaceous cover، a micro sampling plot was established in the center and four other micro plots with the same dimensions were dismounted in each corner of plot. To measure the biomass of litters within plot، micro plots of 50 × 50 cm2 were established. Herbaceous cover and litters were weighted immediately after collecting in the field and were dried in an oven at a temperature of 65°C. The results indicated that tree biomass values، herbaceous and litters were 379/11، 0/213 and 7/65 tons per hectare، respectively. Findings of this investigation indicated that there was no significant relationship between tree layer biomass values، herbaceous and litters with diversity indicators. The results show that we cannot take advantage of biodiversity indicators for proper forest management for correct monitoring the biomass in the study area.

The aim of this study was to compare pH، EC، and chemical concentrations of throughfall (TF) (NO3-، P، k+، Ca2+، and Mg2+) in a natural stand of Fagus orientalis Lipsky and a plantation of Picea abies in Kelardasht forest، Mazandaran province، Iran. Measurements were conducted from July-2012 to October-2013. Gross rainfall (GR) was measured using four manual collectors in a nearby clearing، and twenty manual collectors، similar to the GR collectors، were located in each stand. Duncan tests suggested that there was no significant difference betweenpH means; however، the EC values were significantly different among GR، TFofF. orientalis and TF ofP. abies. There was a significant difference between NO3- concentrations of GR (6. 50 ppm) and TF of F. orientalis (3. 10 ppm). The amount of P+ by F. orientalis (11. 08 ppm) was significantly higher than cf. GR (5. 80 ppm). The concentrations of K+ and Ca2+ were higher in the TF of P. abies stand، 13. 43 and 0. 94 ppm، respectively، cf. TF of F. orientalis، 6. 78 and 0. 49 ppm، respectively، and GR values، 3. 18 and 0. 37، respectively. The average inputs of all elements - except Ca2+- were significantly difference between TF and GR. The average enrichment of elements -except Ca2+- showed no significant changes in the TF of stands and GR. Knowledge of the inputs of nutrients to forest ecosystems is necessary for making a sound and reasonable decision in management and selecting a suitable species for reforestation in derelict areas of the Caspian forests of Iran.

Characteristics of different policy plans and areas force specific requirements for each area. Thus، providing a model is necessary to test the basic features of relations among different structures، service delivery mechanisms and patterns of policy implementations. The aim of this research was to provide a network model for natural resources policies in Iran، despite a lot of efforts; numerous cases of failures are observed due to the lack of a specified policy pattern to manage these resources. Studies revealed that policies and management practices of institutions were the most important factors influencing the natural resources of this region. Natural resources areas and the amount of surface water and groundwater resources is decreasing in this region which indicate the inefficiency of former policies. Results showed that one of the most important factors determining the efficiency of policies and management practices of institutions is quality of relations and arrangement of institutions and agencies in the text of policy- legal documents which has led to an unbalanced distribution of power among them. Unbalanced distribution of power is removable by creating a network approach in codification of these documents and changing the relations and arrangement of responsible institutions and agencies. Finally، a network model for Iran’s natural resources policies was proposed including five main policies including conservation of water and soil، support of forest and pasture، rehabilitation and conservation of forests and pastures، social support of public institutions and providing social services، and the development of exploitation.

In order to investigate the tolerance and impacts of lead and zinc absorption on Acacia victoria three months old seedlings were exposed to Pb (NO3) 2 (in five different concentrations: 0، 50، 250، 500 and 1000 (mg/ L) and ZnSO4 (in 4 different concentrations: 0، 50، 250 and 500 (mg/L) for 45 days. Then، the samples were harvested and some morphological attributes and bioaccumulations of Pb2+ and Zn2+ in different plant tissues were assessed. Results for lead showed that some attributes were affected by lead. Morphological symptoms of lead effects on the leaves were appeared with thin، yellow and brown spots on the leaves in high concentration (1000 mg/L) and more than 70% of total accumulated lead (2518 mg/kg) were accumulated root tissues. Results for zinc indicated that most of attributes were affected by zinc. Morphological symptoms of zinc effects were observed with decreasing in root diameter، height and biomass in high concentration (500 mg/L) and almost 80% of zinc (3046/2mg/kg) was accumulated in root tissues. With respect to bioaccumulation factor، transfer factor and a strong root system، A. victoriae can be suggested as lead and zinc stabilizing and according amount of accumulated lead in above ground parts in high concentration (1000 mg/L) can be considered as lead hyperaccumulators species. Therefore، A. victoriae can be used as a suitable species for remediation of lead and zinc contaminated areas after complementary studies.

Walnut has a high economic value because of the good quality of wood and fruits. So this species has been harvested since many years ago till today and has been introduced as a protected species. The performance of Juglans regia increases in wet years، but reduces in dry years، hence paying attention to physiological and morphological parameters in order to identify the genomic regions related to drought resistant is important for breeding programs in walnut. In this study، genetic diversity by SSR markers has been evaluated. Also، the association of used primers with physiological and morphological traits were analyzed before and after drought stress. 10 SSR primer pairs generated 53 alleles in 62 walnut seedlings. All locies showed significant difference (p≤0. 01) from the Hardy-Weinberg. Dendrogram of the Neighbour-Joining method showed that 62 walnut seedlings divided to four main groups. Analyses of population structure by Structure 2. 3. 1 software identified two sub populations (k=2). Based on association mapping analysis، by using MLM (mixed liner model) method، transpiration، conductance and photosynthesis have been controlled by WGA9 and WGA69 locies in normal condition. In stress condition WGA1 loci showed relationship with CO2 concentration that was covered %75 of variations of this trait. The results of this study can be used in breeding programs of Juglans regia to identify drought resistant varieties.

Many forest residents in Zagros forests rely on fuel wood to meet their energy needs. Nowadays، firewood consumption in Zagros forests plays an important role in forest degradation، because of the limited capacity of the forest ecosystems and intensity of uses. This research was done for understanding fuelwood uses and their amount in Cheshmeh-Ali village and nomads living in the customary land area of this village in southeast of Khorramabad، Lorestan province، west of Iran. The methodology of this research was ethnography and semi-structured and non-structured interviews. Also meter and diameter tape tools were used for measuring diameters of woods. The results showed that each rural household consumes 24. 18 cubic meters of firewood annually. This volume included heating (74%)، baking (13%)، charcoal making (7%) and bath (6%); also each nomad household in six months accommodation in the area، consumed 10. 5 cubic meters of firewood، which included heating and boiling milk and buttermilk (30%)، cooking (26%)، baking (20%)، charcoal making (13%)، bath (6%) and heating the butter to make ghee (4%). The percentage of fuel wood varies between rural and nomad communities، which is related to lifestyle of these communities. Making natural gas distribution network in the area and promoting renewable energy usage like solar and wind energies could reduce the amount of forest woods used for energy.

Carbon dioxide، methane and nitrous oxide are the most important greenhouse gases. The changes of these gases are mainly affected by the variability of carbon and nitrogen ecophysiology indices. In order to study the effect of deforestation and land use change on ecophysiology indices of soil carbon and nitrogen، three land uses including forest area (a less-destroyed stand covered by hornbeam and Persian iron tree species)، rangeland area (bare area covered by sparse herbaceous cover) and agricultural lands (cultivated by rice) were considered. Soil sampling was carried out as random systematic method (ten samples for each land use) from 0-10 and 10-20 cm depths. Soil bulk density، texture، moisture، pH، organic carbon، total nitrogen and ecophysiology indices (microbial respiration، carbon and nitrogen microbial biomass، metabolic quotient) were measured and calculated at the laboratory. The result of ANOVA indicated that the greater amounts of soil microbial respiration، carbon and nitrogen microbial biomass were found in first (1. 22، 665. 66 and 71. 32 mg/kg) and second (1. 10، 508. 44 and 56. 72 mg/kg) soil depths of forest area. The most values of metabolic quotient were devoted to first and second (4. 11 and 6. 23 μg CO2-C mg-1 MBC day-1) soil depths of agricultural area. The findings of this study cleared the effects of different land use on biological indices of soil quality. Following the forest land use change to other land uses، the soil biological qualities decreased.

Urban forests donate many environmental and economic benefits to the cities. The main benefits are reducing indoor heat by shading buildings، absorbing sunlight، reducing ultraviolet rays، cooling the air، and reducing wind speed. In this study different pattern of tree planting as a green belt around an office building (simulation of railway building) was examined for reduction of energy consumption. For this purpose، tree planting (as single and two storied rows) with distance of 5 m and 10 m from the building were considered. Design Builder software was used for modeling. Pinus eldarica and Spartium janceum morphological characteristics such as canopy diameter، height and diameter at breast height of trees measured and were included in the models. Results showed that there are significant differences between the different models and both one and two stories in terms of energy consumption in the building. Tree planting in all directions of building showed the highest reduction in energy consumption than one-side model. Among the one-sided model، tree planting on the west side of building was more suitable while tree planting on the south side of the building did not significantly reduce energy consumption. At both distances، 5 and 10 meters، from the wall in all models، two storied tree planting showed better efficiency than one-storied. The simulation results showed that there is a positive correlation between tree distance from the building and energy consumption.

To investigate the variation between and within same populations of Diospyros lotus based on fruit morphological characteristics، five populations (A، B، C، D، E) were selected along two altitude transects (populations A، B and C with a height of 300، 500 and 700 meters from the sea level، respectively in eastern Band pey forests of Babol and populations D and E with an elevation of 300 and 500 meters in Shastklateh، Gorgan). From each site 10 genotypes were randomly selected and some fruits of each genotype was collected in mid-October. After mixing the fruits، five fruits with three replicates were randomly separated and totally five traits measured. The results indicated that the difference between the populations for all traits was significant (p≤ 0. 01). The mean comparison between populations also showed that in general، population A has the highest amount of trait mean. The analysis of variances within population also indicated that except population A، in other populations for all studied traits، there was significant difference between genotypes. Based on the results of this study، this species has high morphological diversity in fruit characteristics among and within studies populations and the best genotypes in order to gather fruit، were 5 and 6 from population A، 2 and 6 from population B، 3، 4 and 5 from population C، 4 and 5 from D and 5 and 4 from population E.