فهرست مطالب سیدمصطفی مسلمی سیدمحله

This study focused on vegetation classification of Darabkola forest in the middle part of Hyrcanian forests in north of Iran. For this purpose, 139 releves were sampled using systematic- selective method in 400 m grid dimensions by the consideration of indicator stands concept. Based on modified TWINSPAN method and Braun-Blanquet phytosociological method, five associations (Parrotio persicae-Carpinetum betuli, Zelkovo carpinifoliae-Quercetum, Solano kieseritzkii-Fagetum orientalis, Aceri velutini-Parrotietum persicae and  Euphorbio amygdaloidae-Fagetum orientale) and four sub-associations (Zelkovo carpinifoliae-Quercetum castaneifoliae subasso a typical subasso Quercetosum, Zelkovo carpinifoliae-Quercetum castaneifoliae subasso Fagetosum orientale, Aceri velutini-Parrotietum persicae subasso Carpinetusum betuli and Aceri velutini-Parrotietum persicae subasso Pteroetosum fraxinifoliae) were distinguished. Demonstration of plant communities along the first two axes of detrended correspondence analysis (DCA) showed that these associations had almost distinct pattern. Also, results of multiple regression of topographic factors with the two first ordination axes of DCA indicated that elevation was the most important topographic factor in distribution of the associations in the Darabkola forests. In addition, the results of this study can lead to the more efficient management and better protection of Darbakla forest.

Persian honey locust(Gleditsia caspica Desf.) is an endemic tree in the northern forests of Iran and southeastern Azerbaijan, which has low seed germination because of water impermeability of seed. In this research, effects of hot water at 70 °C and 100 °C (5, 10, 15 and 20 minutes), dry heat at 60 °C, 80 °C and 100°C (15, 30 and 60 minutes) and sulphuric acid treatment at two concentrations of 70% and 98% (at immersions of 5, 20, 40 and 60 minutes) were studied on the characteristics of seed germination of this species. Experiment was carried out based on completely randomized design in three replicates. No germination was observed in the seeds treated with hot water (100 °C), dry heat and control, while the seeds treated with semi-hot water (70 °C), sulphuric acids of 70% (60 minutes) and 98% (20 and 40 minutes) obtained 20, 84 and 100 percent of germination, respectively. In general, hot water, warm water and dry heat are not good treatments for seed germination of Persian honey locust seed. It suggests that for seed dormancy breaking as well as seedling production of Persian honey locust,sulfuric acid 98% (with immersion of 20 or 40 m.) to be used.

In this study we evaluate the effects of different types on soil Physical and chemical Properties and plant species biodiversity in the hyrcanian forests of Iran. For this porpuse 33 sample plots were established in 5 vegetation types consist of pure beech (Fagus orientalis), Ash plantation (fraxinus excelsior), spruce plantation (Picea abies), mixed forest and degraded forest. In each vegetation type, a square-shaped surface area of 4 hectares (200 × 200 m2) was separated and the sample plots with an area of 400 m2 (20×20 m) to evaluate the herbaceous community and regeneration of woody vegetation were implemented by systematic random sampling method. A soil sample was taken from a depth of 10-0 cm to assess physical and chemical characteristics of the soil in each plot. The results showed that there was a significant difference between the understory diversity indices in 5 vegetation types based on Simpson and Shannon Wiener diversity indices, and the mixed  and degraded forest have the highest values. Also, the results of the comparison of vegetation biodiversity indices in the regeneration part showed that Margalef, Menhinick, Simpson and Shannon Weiner indices had significant difference among the vegetation types and the mixed forest had the highest values. The results of analysis of variance of soil characteristics showed that only soil moisture content, acidity and carbon percentage had significantly different among the vegetation types. Totally, the results of this study clearly showed that the mixed forest had the best performance in terms of plant biodiversity indices and physical and chemical of soil characteristics than other vegetation types.

In 2005, there were 54 extremely large fires in the forests of Neka, Mazandaran province. This study was carried out to evaluate the effect of physiographic conditions and ecological factors on fire intensity of the above mentioned areas. For this purpose, 19 fire fires were selected from the above mentioned fires with a total area of 250 to 25000 square meters. Quantitative and qualitative data of all trees in each of the selected fire spots including tree diameter at breast height, trunk quality, crown health and the frequency of trees were investigated separately in different spots. The univariate analysis of variance showed that tree type has a significant effect on the extent of fire in the forest. The largest spots of fire were belonged to vegetative types of Hornbeam – Persian parrotia and hornbeam - oak. The CCA and DCA analysis groups hornbeam- hazel and hornbeam- oak forests in one group, beech - hornbeam in the second group and other forest types in the third group. In general, the types of oak-elm zelkova and beech-hornbeam have burned more frequently than other vegetation types during the period. In addition to the tree type, other environmental factors affecting the extent of the fire in these areas were included annual precipitation, annual average temperature and altitude.

Cold stratification is widely used to break dormancy of ash (Fraxinus excelsior L.) seeds. In this study, two groups of seedlings produced by two treatments of ash seeds, one and two-years cold stratification of seeds were investigated with three replications in a completely randomized design in samples of one m2 per plot. Some quantitative characteristics of seedlings including collar diameter, leaf area, stem length, root length, crown height and its biomass and leaves chemical characteristics including organic carbon, nitrogen, phosphorus, potassium and relationship between carbon to nitrogen are examined. The results showed that seedlings density from the two-years old seeds (average of 157.67 seedlings per m2) was significantly higher than that of one-year treatment seeds (average of 61.67 seedlings per m2). Also significant difference between two stratification treatments was recognized for collar diameter, crown diameter, crown height, total height, root length and leaf area index; which were higher values in two years’ cold stratification treatment. Among the chemical characteristics of leaves, only potassium content showed significant difference which was higher in the two years’ cold stratification treatment. In general, we conclude that cold stratification on seed of ash for two years ensure the successful production of ash seedlings in nurseries.

Tending Operation is one of the most important methods to improve equality and quantity of forest stands. In this study, two stands including non-managed (in parcel No.2) and managed stands (in parcel No.13) at the second series of "Berenjestanak" are selected to investigate the structural followed by tending operation. Thirty hectare of each parcel was selected, the statistic method was systematic and random, the netdimensions were 100×100 m and area of each sampling plot was 4000 m. The quantitative and qualitative variables of Acer Velutinum were measured in both stands. Age plantation was 20 years old and distances of each planted trees were 2 × 2 m. Thinning method was positive selection and rotation and thinning also was 3 to5 years. Thinning intensity in each rotation was14% approximately.Thinning operations was createda suitable atmosphereto select the trees. Results of this study show that the mean number in one hectare in sample stand was1365and in managed stand were 977.The average diameter of trees increased from 13.45 cm in sample stand up to 16.40 cmin managed stand. Also the volume average in one hectare increased from non-managed (164.2 m3) up to 188.5m3 in managed stand. The stability coefficient of control stand and managed stand were estimated 105.5 and 99.4 respectively. The statistical tests showed that there was a reasonable difference between the averages of quantitative parameters of two stands in 95% confidence level and equality of averages (zero hypothesis) are rejected regarding to quality, the managed parcel trees are in better conditions comparing tosample stand trees. It is concluded that tending operation had great effects on quantity, quality and stability of stand.