Iranian Journal of Forest and Poplar Research
Year:2010 | Volume:17 | Issue:4 (38)|Papers Count:18

Wild pistachio (Pistacia atlantica F&M.) trees grow in many arid and semi-arid areas of Iran including Khalkhal rigion in Ardabil province. In order to recognize the site demands of this species in Khalkhal forests, six sites (Bane Khalkhal, Kandarag, Mazrae, Nodeh, Jafarabad and Nimehil) were selected and soil properties, climatic data, topoghaphy and growth of wild pistachio were surveyed. Totally, 109 sample plots, each 400m2 with selective sampling method were established. In each sample plot qualitatives and quntitatives characteristics including number of tree, total height, diameter at breast height, basal area, trunk height and crown diameter were recorded. Results showed that wild pistachio is distributed on sites between 760m and 1880 m.a.s.l. with 320mm to 440mm annual precipitation and mean annul temperature between 10.2ºC and 17.1ºC. The soil of pistachio habitats is shallow, with pH between 7.4 and 8.1, and EC between 0.21 d.s/m and 0.39 d.s/m. Six vegatation types of pure Pistacia, Juniperus-Acer with Pistacia, Rhamnus-Juniperus with Pistacia, Rhamnus-Pistacia, Pistacia-Amygdalus with Paliurus and Juniperus-Pistacia with Amygdalus were recognized. The results of inventory showed that mean dbh of wild pistachio trees varies between 14.6cm in Mazrae and 4.6cm in Nimehil. The mean crown diameter and mean height of trees were calculated of 2.48m and 2.9m, respectively.

Identification of phenological stages is the first step to study the plant response to environmental changes, such as climate, temperature, precipitation, fertilization, irrigation and biological control. In order to identify the phenological stages, 100 seedlings were studied at 5-10 days intervals. Stem and leaf length growth were measured by ruler and caliper to draw growth rate curve. Results showed that annual, biennial and 3-years old and older up to productive age of Pinus sylvestris were classified into 10, 10, 9 and 8 groups, respectively. Time of phenological stages was slightly different between biennial and older seedlings. Sigmoidal growth curve of biennial seedlings revealed that the effect of middle part of last year stem on increased seedling height was more than upper part (apical meristem). Hence any parameter that increases middle part of annual seedling will consequently increase the length growth of biennial seedlings. Stem elongation was affected by phenological stage of lammas shoot at the late growth season. Appearance of leaf buds coincides maximum length growth of seedling stem and young trees.

Wild pistachio species, Pistacia atlantica and P. khinjuk, are xerophyte species in Irano-Toranian region, which are scattered in an area about 3200000 ha in four main open forest types of Fars province including: 1) Acer monpessulanum-Pistacia atlantica, 2) Amygdales spp.-Pistacia spp., 3) Pistacia spp. and 4) Quercus brantii-Pistacia atlantica. Regarding the distribution area, elevation, slope and aspect characteristics of wild pistachio, different maps were produced in 1:250000 scale using GIS. The distribution map of wild pistachio was integrated with the other mentioned maps. Analyze of variance and F-test showed that, 57% of habitats of wild pistachio species are mostly distributed between 1000 and 2000 m.a.s.l, 25.5% between 15% and 30% slope gradient and 66% of habitats in southern and northern aspects.

The aim of this research was to study the effect of seed source on morphology, emergence and early vigor characteristics of Quercus brantii Lindl. acorns. The acorns were collected from 4 forest habitats (seed sources) in southern Zagros (provinces of Kohkilouyeh-Bouyer Ahmad and Fars), located in elevations of 850, 1100, 1500 and 2100 m a.s.l. and planted as randomized completely design with three replications in nursery of Shahid Rousta (Ab-baric of Fars, 1700 m.a.s.l.). Results indicated that seed source significantly affected morphologic characteristics of acorns (length, width and weight), emergence (emergence percentage, emergence rate and mean time of emergence), seedling growth parameters (shoot length, shoot dry weight, leaf dry weight and leaf area) (p<0.01). The greatest shoot length, leaf dry weight, shoots dry weight, leaf area and seedling vigor index were related to low elevation seed source (850 m.a.s.l.). Correlation of seed origin with mean time of emergence was significantly positive (p>0.01) and with other seed traits was significantly negative (p>0.01). Since emergence, emergence rate, mean time of emergence, shoots length and seedling vigor index are considered as assessment criteria for seed vigor index in early growth stages, it can be suggested that low elevation seed source has highest early vigor.

Kermanshah province is one of the main regions of poplar cultivation in Iran. Therefore, in order to study of growth situation and wood production of poplar clones, this research was carried out in Mehregan station of Agricultural and natural Resources Research Center of Kermanshah province. Ten poplar clones (Populus nigra) were selected from selection nurseries and cultivated in a Randomized Complete Block Design (RCBD) layout with 3 replications on 3m×3m distance in station and then studied in the first stage during 1993–2001. After first harvesting operation in winter 2002, we started a new investigation which lasts from 2002 to 2007. All shoots were cut except the most vigorous ones. At the end of each growth season diameter at breast height (dbh), height, diameter and height increment and mean wood volume per hectare and annual volume increment were recorded and calculated. Analysis of variance, combined analysis variance and mean comparisons were conducted for all traits over 6 years. Results indicated that P. nigra 56/75, P. nigra 63/135, P. nigra 56/52, P. nigra 56/32 and P. nigra mehregan revealed the highest productive clones which could be recommended for further cultivation in the Kermanshah province.

Crataegus from Rosaceae family is a tree that has medical and ornamental applications. Seeds of this genus have germination problem and may not germinate for 2 to 3 years. There are limited information about germination of different species. Therefore, study on germination of three native species of Iran, Crataegus aminii, C. persica and C. babakhanloui is conducted and the most effective treatment was determined. To evaluate the germination and breaking seed dormancy of three species, an experiment was carried out as a completely randomized design with four treatments and three replications. Seeds were imposed under physical stimulator treatment, including, scarification and warmth followed by cold stratification. Results indicated that in all treatments, scarification is effective for permeability to water of seed coat and breakage of seed dormancy. Germination rate in treatment 4 (impose to running water for 24h, then 3 month warmth, followed by 4.5 month cold stratification) had the highest rate. The highest percentage of germination and vigor were in treatment 3 (sowing the seeds outdoors at the beginning of summer). The number of the seeds that have embryo in each fruit is determined. More than 80% of fruits have only one embryo.

Populus euphratica Oliv. forests in river floodplains of Khuzestan province are degraded heavily. Tree plantation is one of the methods for restoration of these degraded sites. The plantations of Eucalyptus camaldulensis, Acacia salicina and Dalbergia sissoo were established in randomized complete block design in 1993 with three replications along Dez River. Soil macrofauna were collected by hand sorting, using two randomly located 0.25m2 sampling frames at each plot. All macroinvertebrate organisms (macroscopic organisms) in litter and mineral soil up to 25 cm were collected. Totally, 18 samples were collected. In these treatments, earthworm constituted the largest part of soil macrofauna. Earthworm abundance and biomass were highest in Acacia plantation whereas Arthropods did not show any significant differences. Since soil macrofauna was dominated with earthworm, its variations are in line with earthworm. The abundance and biomass of earthworm and soil macrofauna were negatively correlated with the C/N ratio. Lower earthworm abundance and biomass under Eucalyptus plantation could be as a result of its leaf phenolics or soil nitrogen limitation. Totally, it could be concluded that different tree species had various effects on soil macrofauna (especially earthworm) abundance and biomass. As Acacia species increased the soil macrofauna and improved soil fertility, it could be preferred species for plantation in this area.

Remote sensing systems especially hyperspectral remote sensing for recognizing tree species and mapping forest type requires fundamental knowledge of spectral reflectance of desired tree species. A field of remote sensing named field spectrometry dealing with determination of these spectral characteristics tries to provide the spectral libraries for different objects. The main objective of this study was to prepare the spectral signature of the most important forest tree species of the northern forests of Iran. With this respect for the first time, field Spectroradiometric measurements were carried out using a full range spectrometer with Wageningen University of the Netherlands Corporation during the summer 2007. The spectral fingerprint of five tree species namely Fagus orientalis, Quercus castaneifolia, Carpinus betulus, Alnus subcordata and Parrotia persica located in the Experimental Forest of Tehran University was prepared. A total of 321 leaf pile spectral curves were acquired of 107 trees of the mentioned species in altitude gradients between 400m and 2100m under clear and cloudless sky. A total of 100 scan for each leaf pile sample have been performed and averaged. After quality control and noises remove, the spectral fingerprint of the species was prepared along 350-2500nm. In order to investigate the spectral reflectance differences, five important vegetation indices related to leaf chlorophyll content were calculated and statistically analyzed. We conclude that the Vogelmann index and Simple Ratio is more sensitive to chlorophyll content in comparison to the other indices. It shows that hornbeam is significantly different in spectral signatures compared to beech, oak, and alder as well as ironwood with alder and oak being statistically different (p<0.0001, a=0.01). For further investigation of spectral reflectance differences, we propose to make a correlation with extracted chlorophyll content and investigate the suitable vegetation indices related to other biochemical constituents and water content.

The aim of this study was to survey vegetation in relation to some edaphic and physiographic conditions in Arasht catchment (approximately 510 ha) of Kabirkuh protected area in Ilam province. For this purpose, 67 sample plots (20m×20m) in a systematic grid established in the study area. Some factors, including tree and shrub species type, number and canopy coverage were recorded by measuring their small/large crown diameters in each sample plot. In order to record the herbaceous species, cover percentage for each herbaceous species were recorded in four micro–plots (1.5m2) that were defined with Domin criterion. The Canonical Correspondence Analysis (CCA) and TWINSPAN methods used for the site classification and definition of ecological species groups, respectively. Results showed that there are six ecological species groups in the study area. Some soil physicochemical properties and physiographic factors play an important role in recognizing of ecological species groups. The most important factors affecting the establishment and distribution of ecological species groups were soil texture, lime, nitrogen, organic carbon, elevation and slope.

In order to evaluate and compare the capability of ETM+ and LISS III data for forest type mapping in the Zagros forests, a small window of panchromatic and multispectral images of Landsat-ETM+ and IRS-P6-LISS III satellite data were selected from Ghalajeh forests in the Kermanshah province. No radiometric error was found using the quality investigations. Orthorectification of ETM+ was done using 55 ground control points with RMS error of 0.39 for X axis and 0.46 for Y axis and for LISS-III imagery with 34 ground control points with RMS error of 0.67 for X axis and 0.58 for Y axis. Some suitable image processing functions such as principal component analysis, tasseled cap transformation and appropriate vegetation indexes were applied for classification processes. In order to assess the classification results, a sample ground truth was generated using a systematic network with 60m×60m sample area. By computing the canopy cover percent of species, four forest types were determined in the study area. By selecting 25% of samples for each class as training samples, the best band sets were selected using transformed divergence separability index. Classification was performed by supervised method using minimum distance (MD), maximum likelihood and parallel epiped (PPD) classifiers. Results of classification showed that overall accuracy and kappa coefficient for 5 classes for ETM+ images were obtained %44.57 and 0.18 and for LISS III Images %50.6 and 0.32, respectively. After merging the classes of 1 and 2 due to spectral overlapping, the overall accuracy and kappa coefficient for 4 classes using ETM+ images were obtained %61.08 and 0.21 and for LISS III Images, %71.44 and 0.33, respectively. Finally, by merging the classes of 3, 4 and 5, classification was done with two types and the overall accuracy and kappa coefficient obtained %74.1 and 0.37 for ETM+ and %77.7 and 0.41 for LISS III, respectively. Being open canopy cover as well as conflicts between soil and vegetation reflectance caused preventive of obtaining the more favorite results. Result showed fairly more capability of LISS III data in compare to ETM+. Similar research in other regions and using of higher multispectral resolution data is suggested.

This study was conducted to determine the increment and wood production of 22-year-old cypress plantation in Kordkuy region in the north of Iran. Thirty sample plots, each 200m2 area were selected at 101 ha of Cypress man-made forest which was planted in 2m×2m spacing. The samples were taken by systematic random method. In each sample plot, diameter at breast height (DBH) of whole trees and height of witness trees were measured. Moreover, 53 trees were selected as sample trees based on classified diameter in sample plots and felled trees. The data were analyzed with SPSS and Excel softwares. Results showed that the survival rate was 58.72%. The quantitative parameters were calculated and revealed that mean DBH, mean height, basal area, volume and annual volume increment were 15.2cm, 14.02m, 24.35cm2 ha-1, 157.31 silve and 7.15 silve ha-1 y-1, respectively. Results showed the studied plantation compare to Cypress plantations in other parts of the country is promising.

This study was performed in order to consider the effect of management plans on forest, through comparison between qualitative and quantitative characteristics of managed and unmanaged forests. Compartment No. 149 from Shourab district (52.8 ha) and compartment No. 218 from Jamand district (68.7 ha) were selected as managed and unmanaged forests, respectively and were inventoried using a systematic rectangular grid of 80m×125m by 1000m2 sample plots; diameter at breast height, height and stem quality were measured. Results showed that forest type in managed forest has changed from beech-hornbeam to hornbeam-beech. Respecting to species diversity and quality degrees, managed forest was changed negatively in comparison to unmanaged forest. In managed forest, it's appeared that hornbeam populations have increased and as a result society movement toward climax has been slowed down or even prevented. In managed compartment comparing to unmanaged one, hornbeam lost advantage of density in diameter classes, posterior to beech. Also the result of statistical test showed that difference in stock volume between beech and hornbeam species in two compartments is significant.

The aim of this study was to investigate the possibility of cryopreservation of Eucalyptus microtheca seeds at -196ºC, using Liquid Nitrogen (LN). Before transferring the seeds into LN, three pre-treatments including Plant Vitrification Solution 2 (PVS2), Desiccation and Glycerol 30% was applied. The treated seeds transferred into LN for period of one week. The seeds removed from the LN, subjected to heat shock (+42ºC) for 2 minutes, blotted and transferred both onto moist paper in petri dishes and pots, filled with soil and pit moss. The petri dishes and pots, transferred into germinator (+24ºC) or greenhouse (+20ºC), respectively. Subsequent of cryopreservation period, seed germination and recovery was high, there were no significant differences between cryopreserved and control seeds in germinator and greenhouse conditions. Furthermore, there were no adverse effect or abnormality observed in seedlings developed from cryopreserved seeds. Results showed that, long-term preservation of E. microtheca seeds under LN (cryopreservation) is promising.

Vast areas of Iran are located in Irano-Touranian phyto-geographical region. Exploitation of forests within this region during past decades has changed these valuable forests to fragile ecosystems. Considering the most important ecological function of these forests, namely soil and water protection, the Sarsakhti oak forest was declared as protected area. In order to study the changes within last 50 years, crown canopy of forest has been studied as main factor using aerial photographs of 1955, 1995 and full callipering of the whole 20 ha stand in 2007. Results showed that the crown canopy density was decreased 6% (from 41% to 35%) between 1955 and 1995 but increased again in 2007 to 40%.

World increasing demand for wood production, caused the increasing impact to natural forest. Short term exploitation and improvement of wood production have been reduced these impacts. Considering the special characteristics of poplars, plantation of these fast growing species could be a proper solution to solve the problems. This research was carried out with the aims of increasing wood production by collection of better and more adaptable poplar clones to climatic and edaphic condition in Markazi province. In this research, 21 poplar clones were compared using the complete experimental block design in 3 replications. ِDiameter at breast height and height of trees were recorded and total volume and volume increment were calculated. Based on results, we concluded the following results: higher diameter, height and volume increment were found in Populus nigra 56.72 with 20.7 cm, 17.57m and 36.55 m3/ha/years, respectively. Other promising clones are P.nigra 72.19, P.nigra 72.5 and P.nigra betulifolia. The poorest results were observed on different clones of populus alba.