بررسی ویژگیهای مورفولوژیکی و کمی و کیفی توده های راش ایران از دیدگاه حفاظت ژن

گونه راش یکی از فراوانترین و از نظر اقتصادی مهمترین درختان جنگلهای شمال ایران است. تعیین ساختار هر توده و ترکیب آن با خصوصیات جنگل شناسی که شامل آمیختگی، سن، ساختار عمودی یا اشکوب بندی، ساختار افقی، وجود یا عدم وجود روزنه، تاج پوشش، انبوهی، وجود و یا عدم وجود زادآوری یا زیراشکوب درختی و درختچه ای است می تواند ما را در دستیابی به یک مدیریت مناسب و فراگیر، یاری نماید. در این پژوهش خصوصیات مورفولوژیکی و ویژگیهای ژنتیکی در 14 قطعه نمونه نیم هکتاری در راشستانهای شمال ایران مورد بررسی قرار گرفته است. هم چنین سعی شده است نقش عوامل انسانی و مدیریت راشستانهای مورد نظر (شیوه های جنگل شناسی بکار رفته) بر این خصوصیات مطالعه شود.   تنوع ژنتیکی بالای راش در راشستانهای ایران (هتروزیگوزیتی مورد انتظار= 191/0) حاکی از توان سازگاری این درخت در جنگلهای خزری می باشد. از آنجایی که رابطه مثبتی بین تنوع ژنتیکی و درصد پایه های چند شاخه و غیرمستقیم (بد فرم) وجود دارد، بنابراین از لحاظ نظری انتخاب و حفظ درختان خوش فرم برای زادآوری در توده ها که در اثر فعالیتهای مدیریت تحت شیوه تدریجی پناهی اعمال می گردد می بایست با احتیاط با آن برخورد شود. زیرا انتخاب برای حفظ برخی ژنوتیپها از مهمترین فرایندهایی است که در طی عملیات مدیریت جنگل باعث تغییر در گوناگونی ژنتیکی درختان می گردد. در طی این فرایند میزان برخی ژنها به شدت کاهش می یابد و بنابراین، باعث کاهش گوناگونی ژنتیکی می شود که می تواند روی سازگاری آینده تأثیر بگذارد. بنابراین یک شیوه جنگل شناسی مناسب می بایست ضمن حفاظت توده ها، همزمان با برداشت و استفاده از محصولات و خدمات جنگل در حال حاضر، کوششی برای تأمین محصولات، کالاها و سایر خدمات در آینده نیز باشد. به این ترتیب میزان و چگونگی استفاده از منابع موجود در حدی خواهد بود تا تأمین مناسب و مستمر آنها در آینده تضمین گردد. همان گونه که مطالعات اخیر نشان داده اند در میان شیوه های جنگل شناسی دو شیوه تک گزینی و شیوه گروه گزینی با ساختار توده های طبیعی راش شمال ایران همخوانی بیشتری دارد. در این پژوهش نیز توان سازگاری بالای برخی مناطق (نکا در ارتفاع 900 متر و خیرود در ارتفاع 600 متر از سطح دریا با 14 آلل نادر و مختص به محل) در مقایسه با سازگاری محدود برخی دیگر (مثل خیرود در ارتفاع 1200 متر و گرگان در ارتفاع 2000 متر از سطح دریا با 2 آلل نادر و مختص به محل) تأکیدی بر حفاظت راشستانهای شمال ایران و انتخاب شیوه جنگل شناسی مناسب با هدف تولید مستمر و حفاظت از تنوع ژنتیکی توده های راش می باشد. determination of beech (fagus orientalis lipsky) seeding cycle in ziarat forest   s. z. mirkazemi1 and a. r. mirbadin2   abstract the trail was conducted at ziarat forest (longitude: 54º 25´ east, latitude: 36º 43´ north, altitude: 650-2350. asl) of caspian region of iran in order to identify the seedling cycle of f. orientalis. twenty seven dominant beech trees were selected for quantitative and qualitative measurment. after soil and ground cover sampling and tree measurment, the trees were cut down and a disc sample was taken from each tree&apos;s stump. the discs were analyzed to study the annual rings. the results showed that: 1-fagus orientalis has two seeding types, heavy and light. 2- the minimum age of seeding is about 49 year when is often associated with light seeding. 3- the heavy seeding begin at age of 57 year. 4- at a same site, different seeding cycles were observed during the living period. 5- the light and the heavy seeding repeat at 2-6 and 3-27 year period, respectively. 6- natural regeneration depends on the light seeding cycles due to their frequent occurance. 7- there was a relationship between the averag decerese of annual ring growth rate and seeding types as follows: a. if decrease of annual ring growth rate is more than 1mm, there will be a heavy seeding cycle. b. if decrease of annual ring growth rate is between 1mm and 0.31mm, then there will be alight seeding cycle. c. if decrease of annual ring growth rate is less than 0.31mm, there will not be a seeding cycle.   key words: forest, beech, fagus orientalis, seeding cycle, growth, age. effects of eucalypt plantation on understory plant cover and some soil parameters in comparison to next natural forest in astara of iran   f.moraghebi1, s. a. a. korori2, b. khanjani-shiraz3, m. teimouri2  and a. hemmati3   abstract about 30 years ago, a eucalypt species trial was conducted in caspian coastal forest of iran at astara, after clear felling the natural querco – carpinetum forest type. the aim of the study was investigation the effect eucalypt plantation on understory plant cover component and soil properties .for this purpose, the understory species and their frequency was determined in both eucalyptus plantation and next natural forest. the sorenson method was used to study the heterogeneity homogeneity of plant communities .furthermore, the soil na+, k+, organic matter and electrical conductivity (ec) were measured. results showed that there was only 54% homogeneity between the understory plant cover of two sites according to sorenson index that indicated the significant effects of eucalypt plantation on kind and frequency of species. the amounts of na+, k+, organic matter and ec was less in eucalypt plantation site  than the natural forest site. the results showed that there was only 54% homogeneity between the understory plant cover of the two sites according to sorenson index and significant effect of eucalypt plantation on flora. the amount of na+, k+, ec and organic matter in eucalypt plantation site was less than the natural forest site. it was concluded that eucalypt plantation on natural forest sites should be limited due to its significant effects on sol and flora.   key words: forestation, eucalyptus, natural forest, plant understory. effects of using aquasorb polymer on irrigation of pinus eldarica, olea europea and atriplex canescens   a. pourmeidani1 and h. khakdaman1   abstract this experiment was carried out in 2001 in order to determine the effect of aquasorb polymer on irrigation of three plant species in hossein abad station of sand stabilization of qom province. the factorial statistical method under randomized compete blocks design whit three replicates was used. there were two factors: species (atriplex canescens, pinus eldarica medw. and olea europea l.) and aquasorb polymer (0.0%, 2.0%, 4.0% with irrigation interval three times were than normal interval) and control irrigation with normal interval). the variables were: soil water content (%) before and after irrigation (at depths of 25 and 50 cm) and survival % one, three and six months after plating. the anova and duncan tests were used to analyze the data. the results showed that there were significant differences (p<0.01) in respect to survival% between the planted species. the species atriplex canescens p., olea europea and pinus eldarica obtained the greatest survival percentage, respectively. the effects of aquasorb polymer treatments on the measured variables (except soil water content ratio of after irrigation to before irrigation at 50 cm depth) were significant (p<0.01). there was a not significant differences between the levels 2.0 and 4.0% of aquasorb polymer on one hand and between these levels and control irrigation regime on another hand. it is suggested to apply aquasorb at level of 2.0 instead of normal irrigation for planting three species at similar climate and soil conditions as the studied site.   key words: aquasorb; irrigation, polymer, pinus, olea, atriplex distribution of different species of pistachio in markazi province of iran   h. zahedipour1, m. fattahi2, h. r. mirdavoodi akhavan1, gh. r. godarzi1 and z. azdoo3   abstract considering appropriate adaptability of different wild species of pistacia in different arid and semi-arid environments of the country, as well as their high value from point of view of resin and other chemical production; oil; and pharmacological use of their seeds, studying their habitats in different areas of markazi province, (as a sub-project of the national project under the title of “the study of pistacia distribution and related influencing factors in iran) seems to be important. in this project the basic maps including topography, soil, climate, geology, and landuse of the area (1:50000 scale) were purchased and digitized. then the areas which were covered by the wild species were visited, recorded by gps and digitized. in order to study the quantitative and qualitative characteristics of the species, five sample plots (1600m2) the tree parameters were: density, total height, stem diameter, crown height, crown diameter, type of regeneration, stem and crown health, number of male and female pistachios, amount of seed production and seed quality. after establishing the dem of the areas, aspect and slope maps were also produced using dfdx and dfdy filters of ilwis academic program package. on the basis of this investigation the following results were obtained. -twenty polygons of wild pistacia species of (areas of 2216 ha) were recognized in markazi province. - the species - environment relationships including: slop, aspect, climate, landuse and soil were determined, using maps integrating and data overlying methods.   key words: pistachia atlantica, pistachia khinjuk, amygdalus, tree parameter. survival and growth of 10 broadleaved and needleleaved tree species in fars province   m. r. negahdar - saber1, m. hamzehpour1 and l. joukar1   abstract importance of wood as a basic material in industry, along its broad uses and diverse by-products leads us to change our direction from exploitation of natural forests towards artificial forest plantation. this is done mainly by selecting suitable and fast-growing species. understanding the adaptation and the growth potential of forest trees in different environments is one of the earliest steps in approaching this great goal. in this study, growth and survival trend of ten forest tree species including pinus brutia, cupressus sempervirens var. horizontalis, cupressus arizonica, pinus eldarica, elaeagnus angustifolia, robinia pseudoacacia, quercus brantii, ailanthus altissima, fraxinus rotundifolia and pinus nigra in a three hectare forest area in kamfirooz, fars province were investigated under rcbd** (four replicates) for ten years (1993-2003). the area is located at longitude of 52º 10&apos; e and latitude of 32º 22&apos; n. seedlings were planted at spacing of 3×3m (44 seedling at each) the seedlings survival, collar diameter and height were measured twice a year, at beginning and at end of growth period. the spss program, and anova and duncan tests were used to analyze the data. the results showed that there were significant differences (p<0.05) between the species performances and there were significant relationship between the species height and diameter and between the species growth parameters and the growth periods. p. brutia and c. arizonica had significantly better growth and survival compared to other species. on the other hand, pinus nigra showed the least survival, and q. brantii showedthe least height and diameter growth. overall, it seems that the needleleaved species, except p. nigra,are more successful than thebroadleaved species in respect to their survival, diameter and height parameters.   key words: diameter, height growth, elimination, species trial, zagros effects of different chemical and livestock fertilizers on growth of caucasian oak seedlings in two nurseries at caspian region of iran   a. rahmani1 and m. khoshnevis1   abstract two experiments were conducted to determine the effects of n, p and manure fertilizers on growth of quercus castaneifolia c.a.meyerin shahrposht and koloudeh nurseries (north of iran). the trial was conducted under factorial statistical method, randomized complete blocks design and three replicates. the factors were ammonium sulfate at three levels: 0, 40 and 80 kg/ha), triple superphosphate (at three levels: 0, 80 and 120 kg/ha) and manure (at two levels: 0 and 30 t/ha). the shoot (height and collar diameter) and the root (length, diameter and dry weigh) parameters were measured at each plot, using 15 and tree seedlings, respectively. in shahrposht nursery the height and the collar diameter of the seedlings were not affected significantly by any of the fertilizers. seedlings growth in koloudeh nursery was improved in fertilized plots, especially with manure application. the results clearly show that there was significant difference between koloudeh and shahrposht nurseries in response to fertilizers.   key words: nursery, fertilization, growth, caucasian oak, seedling, rootshoot. 1- member of scientific board, research center of agriculture and natural resources of golestan province, gorgan, i. r. iran. e- mail: zaidmirkazemi@ yahoo.com 2- member of scientific board, research institute of forests and rangelands, tehran, i.r. iran. e-mail: alirezamirbadin@ rifr- ac.org 1- member of scientific board of azad university. e-mail: [email protected] 2- member of scientific board of research institute of forests and rangelands. p.o.box. 13185-116. tehran- i.r. iran. 3- researchexperts of research center of agricultural and natural resources of gilan province, gilan, i. r. iran. 1- members of scientific board of qom agriculture and natural resources research center. 1- member of scientific board of agriculture and natural resources research center of markazi province, e-mail: [email protected] 2- member of scientific board of research institute of forests and rangelands, tehran. p. o. box: 13185-116., tehran, i. r. iran. 1- members of scientific board, fars research center of agriculture and natural resources. e-mail: [email protected] *- randomized complete blocks design   1- member of scientific board, research institute of forests and rangelands, iran. emaol: [email protected]