مجله جنگل ایران
سال ششم شماره 2 (تابستان 1393)

In traditional methods، measurement of tree height in broad-leaved forests، particularly in uneven-aged، high density and multi-storey stands is difficult and time-consuming. In the growing season of 2011، airborne laser scanner system was used to acquire Light Detection and Ranging (LIDAR) data by a sampling density of 4-5 points/m2 in a broad-leaved forest، northern Iran (Shast-Kalate forest located in southwest of Gorgan). LIDAR data was used to estimate the height of individual trees. Hundred individual tree samples belong to two species، Acer velutinum and Carpinus betulus، were selected. The trees were located in dominant storey and/or without overlay with adjacent trees. Heights of trees were measured using Vertex 1V. Center coordinates of the sample trees were determined using DGPS system and Total Station with distance and angle. Sample trees were detected in laser point clouds using their center coordinates and crown diameter. The heights of sample trees were extracted directly from laser point clouds. Linear regression model between the heights of trees in the field measurement and laser point clouds was yielded coefficients of determination (R2) (0. 96، 0. 95)، RMSe (1. 05m (6%)، 1. 48m (6%)، and relative error (4%، 3%) for A. velutinum and C. betulus، respectively. Mean differences between tree height of laser point cloud and field measurement were achieved 1. 04m and -1. 53m for A. velutinum and C. betulus، respectively. The results clarified that considering the acceptable of LIDAR height data، rapid prevail of data and its easy access for users، the employment of LIDAR data for estimating tree height in other places of northern forests of Iran is advised.

In order to survey some phenological phenomena of Kair with climate and physiography properties, this study was carried out in the south-east of Iran from 2008 to 2011. In the first step, distribution of species was recognized in Hormozgan and Balochestan provinces and then 13 habitats were chosen. These habitats were visited in 2-3 week intervals annually. Three trees were marked in each site and were monitored during four seasons and its phenological stages (time of bud break, flowering, fruiting, ripening, fruit, and leaf shedding) and other characteristics were recorded. Climatic data were gathered and phenological stages were analyzed. The results of phenological and meteorological data indicated that the growth patterns of Capparis decidua may alter with fluctuations of drought, annual temperature and precipitation. The phonological stages are repeated two or three times every year. Kair phonological stages are long, Flowering starts during March and continues up to October. It flowers in three seasons: March–April (spring), June-July (summer) and September-October (Autumn). Flowers become fruits within 70 to 90 days and simultaneously, both flower and fruit appear on new shoots. In the northern and western habitats, phonological stages are limited and only occur once or twice a year. But in all conditions, amount of growth degree days (GDD) required for ripening seed is the same and equal to 931ْ C.

The aim of this study was to measure the allocative- economical efficiency of joint-stock company of Shafaroud Forest using Data Envelopment Analysis. In this study, data during period of 10 years (2002 to 2011) with two inputs (production prices, total cost) and two outputs (sales of forest products, total revenue) was collected from the company financial balance sheets. Due to the importance of this company for supplying wood products in the Guilan province, advanced models were used to estimate the cost, revenue and profit efficiency. Results indicated that this company in terms of allocative- economical efficiency was completely efficient (100% or scored 1) in (2006), (2008) and (2010) by all of these models, but the company did not have high productivity in other years. This result can be due to the nature of theses input oriented advanced models that focus on optimal inputs allocation, and could be known as a result of optimal usage and resources management.

The aim of this research was to estimate the ecohydological parameters of the canopy covers including canopy storage capacity (S) using the Pereira method and the direct throughfall coefficient (p) of individual trees of Pinus eldarica planted in the Chitgar Forest Park with a semiarid climate. To measure GR, six rain-gauges were installed in an open area neighboring to the trees. Throuhgfall (TF) was measured using the twenty rain gauges randomly located underneath the crown of the five individual trees. Rainfall interception (I) was calculated as the difference between GR and TF. From January 2011 to January 2012, 224 mm of cumulative GR in fifty-one rainfall events was recorded. P. eldarica trees intercepted 35.9% and 47.5% of the incident rainfall on cumulative-based, and event-based (each GR), respectively. The mean value of S estimated by the Pereira method, and p were found to be 0.77 mm (SE ± 0.08), and 0.44 (SE ± 0.07), respectively. The results indicated that I allocated a considerable portion of GR in P. eldarica trees in arid and semiarid regions. Hence, I should be considered while calculating the water budget for P. eldarica plantations. S which is a critical parameter for controlling I can be usefully estimated by a sole newly proposed method by Pereira for individual trees.

Identifying the best attributes of seedlings for evaluation of quality of them has an important role in successful reforestation projects. In this study, some morphological characteristics were used for evaluation of quality of oak seedlings. Seedlings were sampled by method of systematic-random from the planting bed in nursery in late February. Statistical analyses were done after measurement of morphological characteristics. Results of correlation analysis showed that the root collar diameter (RCD) had the strongest correlation with other morphological characteristics. Parameters of leaf area, root volume, number of first order lateral roots, stem height, and length of the main root, respectively, had lower correlations with others, then had less important in seedling quality evaluation. Therefore, in according to this study the RCD is the best characteristic for seedlings quality evaluation of this species in nursery.

To identify petrified tree remains from Upper Pliocene of NE Tabriz, we prepared thin sections from transversal, radial and tangential surfaces, according to specific methods. Whereas possible the slides were examined by optical microscopy. Data related to vessels, rays, parenchyma and other wood elements were determined. Following IAWA list of microscopic features, we made the elementary descriptions and via Inside wood list of fossil woods of Angiosperms, the identification was completed. Results showed that the structure of fossil sample was the same as Angiosperms. Growth ring boundaries indistinct, wood diffuse-porous, ground tissue consists of thin walled fibers, rays abundant, and solitary vessels, were common. The material has been referred to Ash fossil species of Oleaceae at this stage.

The study area with 170 hectares is located in the north of Rudbar and between 1010-1560 m a.s.l. There is not any harvesting in the study area due to a lack of a road network. This research has been carried out to identify the floristic composition, life forms and chorology of all plants in this area. The final results of the studies on floras showed that 47 plant species belonged to 46 genera and 37 families. The dicots with 34 taxa were the richest group of flora followed by monocots with 7 taxa, and Pteridophytes with 6 taxa. Dominant life forms include geophytes (49%), followed by phanerophytes (23.4%). From the chorological point of view, the largest proportion of the flora belongs to the Euro-Siberian elements (42.6%) followed by Pluriregional elements (14.9%), Euro-Sibirian/ Mediterranean/ Irano-Turanian and Euro-Sibirian/ Mediterranean (10.6%).

This study extracts diagnostic species of plant communities of Khybus protected forest based on statistical analysis of phytosocilogical data. The affinity of vascular plants was calculated using a statistically defined coefficient of fidelity. Additionally, with the development of Total Phi Fidelity Index, TPFI, as a new criterion in fidelity attention with sharpness and uniqueness indices the evaluation of plant communities was created. It is shown that there are 33 diagnostic species in the plant communities without box tree (Buxus hyrcana Pojark.) based on Φ coefition in which the contribution of herbaceous species were 76.7% (22 species) and the contribution of woody species were 33.3% (11 species), while in the list of diagnostic species in the box tree plant communities (with 7 species) the herbaceous species were never presented. Chi- square goodness of fit test (χ2= 234.97, df= 25) in reviewing the consistence of TPFI and TWINSPAN are not independent and they are applicable together with 99% probability. In this case, conformity and correlation between the two mentioned methods were assessed 78.9% and 93.5% from basis of Kappa index and Spearman correlation coefficient. Also, quality assessment of TPFI and TWINSPAN results based on sharpness and uniqueness showed that the mean values ​​of these two indices in the provided vegetation units by the TPFI method (Sh=33.76, U=88.74) is consistently higher than the submitted plant communities by TWINSPAN (Sh=29.98, U=71.51). Totally, we are concluded that TPFI method can be used as a new approach in improvement of TWINSPAN results in plant community classification.

Smoke-tree(Cotinus coggygria Scop.)is one of the endemic valuable shrub species of Iran which has only distributed in the Arasbaran Forests. Natural regeneration of this specie is mostly asexual with the shape of root-sucker, and its sexual reproduction is rarely possible. Considering the importance of this specie as well as difficult germination of the seeds naturally, an effort was made through the present study, for the first time in Iran, to examine the effects of several treatments on the improvement of seed germination of this specie, and to introduce the best treatment. In order to break the physical and physiological dormancies, the seeds were soaked in 98% concentration sulphuric acid for 5 and 50 minutes and cold stratified at 4°c for 30 and 60 days. In addition, both of the mentioned treatments, soaking in 98% concentration sulphuric acid for 5, 20 and 50 minutes with cold stratified at 4°C for 60 days, were simultaneously utilized to break both physical and physiological dormancies. The experimental design was completely randomized design (CRD) with three replications in which 30 seeds were planted per replicate. The results of analysis of variance showed that the selected treatments had significant effects (p < 0.01) on all the traits including germination rate, germination speed, and seed vigor index. Furthermore, comparison of the means resulted by the Duncan tests revealed that the best results were obtained by simultaneously application of both the treatments of soaking in 98% concentration sulphuric acid for 20 minutes and cold stratification at 4°C for 60 days. Totally, the results of this study demonstrated the positive effects of the selected treatments on breaking the seed dormancies of this shrub, and the results may be considered in reforestation programs.

Cryopreservation by storing explants in liquates nitrogen (LN) at -196°C is a new and most important method of preserving plant species for a long period. Most of seeds, vegetative organs, cells and pollens can be preserved for a long time, by cryopreservation. Cryogenic conditions stop much of the metabolic processes of the cells and, period of preservation dramatically increases.Three pretreatments including vitrification (PVS2), desiccation and 30% glycerol were applied on the seeds of Robinia pseudoacacia L. collected from Chitgar Park at west of Tehran, before transferring them into LN. After one month storage in LN the seeds transferred into warm water bath at +42 °C as a postreatment. Then they were germinated under laboratory and greenhouse conditions. Different attributes including seed germination percentage, root and shoot lengths, germination speed, root/shoot length ratio and seed vigor index (VI) were recorded. The attributes were significant at 1% level of probability revealed the cryotolerance of the seeds. In greenhouse experiments, plants developed from cryogenic seeds grew normally and did not show any abnormality compared to those of the control plants and desiccation showed the best effects on survival rate and other attributes of the cryopreserved seeds. The results indicated that the cryopreservation (-196 °C) technology can be used for long-term preservation of the Robinia pseudoacacia seeds.