quantitative characteristics

Correct performance to reduce the sensitivity of forest stands to environmental hazards requires knowledge and proper understanding of its effects on the trees. The tree height-diameter ratio is a tool that is known as an index of tree resistance and stand stability. The present study evaluated the tree's height-diameter ratio in a mixed species natural forest stand in a protected forest in Arasbaran to obtain basic information about the stand stability.

500 sample trees (DBH ≥ 7.5 cm) were randomly selected from the most abundant species present in the region to include all types of diameter classes from the lowest to the highest that are present in the stand. Each tree is one sample in this method. The diameter at breast height and the tree height were measured to calculate the height-diameter ratio. The height-diameter ratio of the stand and every tree species was calculated by dividing the tree's height by the diameter.

The results of this research showed that the value of the height-diameter ratio was 54.31 at the stand level. In addition, this ratio value was 54.93 for maple, 55.04 for hornbeam, 54.63 for ash, and 52.64 for oak at the species level. The result showed that the trees were in the stable category in terms of this ratio. The changes in the height-diameter ratio in different diameter classes showed that the value of this ratio decreased with the increase of the diameter classes. The correlation analysis showed a high, positive, and significant correlation with the tree’s height. Oak and hornbeam species had the highest significant correlation between height and height-diameter ratio (0.718 and 0.729, respectively).

Computing the value of the height-diameter ratio is considered necessary in quantifying the resistance against adverse environmental factors (snow, storm, and wind) and is considered a management issue. Estimating the value of this coefficient determines the diameter class in which instability occurs for any tree species, and it is valuable and practical in future silvicultural and protection planning because of the tree's proper spatial arrangement in the dbh classes in the stands, the density of the stand, and the critical values of the heigh-diameter coefficients are regulated such that the stability of the stand was not threatened.

In a proper planning of the forest sector, the preparation of quantitative and qualitative maps is a management requirement and is unavoidable for sustainable development. For this effective planning, the latest information on the types of characteristics that are important in decisions regarding the optimal use and protection of forests are needed. This study conducted in order to the modelling spatial estimation of some quantitative characteristics forest using topographic features and its spatial mapping in District-3 of Sangdeh Forests.

Characteristics of number, basal area and volume per hectare were calculated by surveying 150 sample plots (1000 m2). Primary topographic features of altitude, slope, aspect, profile curvature, flat curvature and tangential curvature and secondary topographic features including wetness index and solar radiation were extracted from digital elevation model with 10m resolution. Then, the relationships between forest quantitative characteristics and topographic features were analyzed and modeled using non-parametric method random forest, support vector machine and also parametric multiple linear regressions. Models were evaluated using 30% of the samples.

Bias and root mean square error percentages were calculated to select the appropriate model and the results showed that the support vector machine method had the best results for estimating all three measured characteristics. In estimating number per hectare, the polynomial-3 function with mean square error values ​​and skewness is RMSE = 9.59 and Bias = 1.62, ground cover with radial base function (RBF) and values ​​of 53.5, respectively. 30% RMSE and 1.32 - =% Bias and volume per hectare with polynomial function of third degree and values ​​of RMSE = 37.62 and Bias = -0.51 were selected as the most appropriate model. The results also showed that the topographic variables of aspect, altitude, solar radiation and tangential curvature had the most influence on the modeling process.

The selected model in this study was able to provide some of the necessary information for forest management, but the model alone cannot explain all the reasons affecting the characteristics, so it is recommended to combine other factors such as climatic conditions, latitude, geology, and remote sensing techniques, which play a major role in explanation and interpretation, to improve the accuracy of the forecast.

The fagus orientalis lipesky species includes around one-third of width and correspondingly, the standing volume in the mixed and partly pure stands of northern forests of Iran.. Present research has been carried out to investigate the effects of topographic factors on quantitative characteristics of oriental beech species in Nav Asalem forestry plan. According to purpose of the research, breast height diameter and height of the oriental beech trees were measured in three altitude levels (800 to 1650 m), five slope classes (0 to 50) and four main geographical classes and recorded on the corresponding forms. The results of one-way variance analysis test showed that two factors of slope and the sea-level altitude had significant effects on quantitative characteristics of oriental beech species wherein Dunkan’s test was used to compare the means and eventually, the results showed that the lowest and highest rates of quantitative characteristics existed respectively in heights of 1300-1440m and 1440-1650m. Also, studying the slope, the highest diameter, cross-section and height of the beech trees were obtained in a slope of 40-50 percents. Thus, due to the nature and ecological characteristics of oriental beech and since the best habitats for the trees of this species to have the greatest diameter and height are the upstream and sloping regions, the results of this research show that Nav Asalem forest habitat is one of the best habitats of the target species.

Light intensity is one of the most important environmental factors affecting the growth, yield and quality of fruits and vegetables. Salicylic Acid (SA) alleviates the negative effect of high and low light intensity. In order to evaluate the effect of interaction between light intensity and SA  on physiological properties, yield and fruit quality of tomato (Solanum lycopersicum L. cv. Super Beta F1), a split plot based on randomized complete block design experiment with three replications was carried out at Moghan College of Agriculture and Natural Resources located in Ardabil province, Iran in 2015. The treatment were included differentlight intensity levels (100, 75 and 50% light intensity) and SA (0 and 2 mM). Results revealed that the plant fresh and dry weight was decreased significantly with decreasing light intensity, especially without SA treatment. The leaf stomatal conductance and Fv/Fm ratio were increased with decreasing light intensity. The application of SA improved leaf stomatal conductance and Fv/Fm ratio. The application of SA caused increase in truss number and fruit number per truss under different light intensity levels. Tomato yield in full light intensity treatment and treated with SA was 116% higher than tomatoes yield grown in 50% light intensity and without treatment with SA. The highest and lowest value of total soluble solid, fruit firmness, EC and pH of fruit juice were obtained in full light intensity and 50% light intensity, respectively. In general, it is concluded that tomatoes grown in full light intensity has better yield and quality. SA application improves the quantitative and qualitative properties of tomato in different light intensities.

The effect of foliar application of zinc sulfate and seaweed on qualitative and quantitative characteristics of local Kermanshah cantaloupe (Cucumis melo L., Cantalupensis Group) cv. Kalak was investigated. After sowing seeds in the field, the plants were sprayed in three stages including the 4-6 leaf stage, flowering and after the fruit set. The experiment had a factorial design based on the randomized complete block design with 9 treatments including various concentrations of zinc sulfate (0.5 and 1 g L-1) and seaweed (0.5 and 1 g L-1) and was repeated three times. The results of analysis of variance showed that zinc sulfate at 0.5 g L-1 and seaweed at 1 g L-1 had significant effects on the weight, length and diameter of the fruit, the weight of the fresh fruit, fresh and dry weight of the plant, and fruit firmness. The highest amount of vitamin C was observed in zinc sulfate at 1 g L-1 and seaweed at 0.5 g L-1. The highest total seed weight was obtained in zinc sulfate at 0.5 g L-1 and seaweed at 1 g L-1. Foliar application of zinc sulfate and seaweed did not have a significant effect on total soluble solids (TSS). However, zinc sulfate at 0.5 g L-1 increased the amount of titratable acid (TA) in the fruit juice. The highest amount of the TSS/TA ratio of the fruits was observed in application of seaweed at 1 g L-1. Overall, the findings of the present study indicated that simultaneous application of zinc sulfate and low concentrations of seaweed extract has a significant effect on many qualitative and quantitative characteristics of “Kalak” Cantaloupe and can be recommended as a biofertilizer.

This research was started in 1995 in order to investigate the effect of thinning on the young plantations of velvet maple (Acer velutinum Boiss.). The silvicultural interventions comprised three main treatments (medium and heavy thinning), two secondary treatments (3-year and 5-year rotations) in the fully randomized design with three replications. There were 9 sample plots in the experimental design with an area of 0.3-0.4 hectare each. A full calipering of the future trees was done after 20 years and 6 thinning operations. The results for DBH, total height, trunk height and trunk diameter showed significant differences between the control treatment and thinning intensities. However, no significant difference was observed between the secondary sub- treatment (circulation 3 years and 5 years) and the intersection between the main and sub plots treatments for DBH, total height, trunk height and trunk diameter. For the intensive thinning treatment, the largest value of 32.95 cm was observed for the DBH, while the lowest value of 27.39 cm was observed for the slight thinning. In addition, the largest height of 24.42 m was observed for intensive thinning, whereas the lowest rate of 23.63 m was observed for the control treatment.

To assess the changes in qualitative and quantitative attributes at the end of a period of forestry plan implementation, a portion of the Jojadeh zone with an area of 1270 ha was selected. Data were collected from 265 permanent plots in a systematic random design (1000 m2 plots and150 × 200 m grid size) in 2004 and 2014 to facilitate a comparison. In each plot diameter, species, quality grade, height of control tress and quality of regeneration (in 100 m2 microplots) weree measured. During the ten-year period, approximately 14000 silve of growing stock was marked within a single tree selection cutting system. The results showed following figures for 2004: the average number of trees per ha=173, volume per ha=318.36 silve, basal area per ha= 25.87 m2, diameter of basal area= 43.93 cm and Lorey’s mean height= 25.31 m. The values in 2014 were 175, 360.24 silve, 28.31 m2, 43.39 cm and 26.40 m, respectively. Apart from number of trees per ha, significant differences were observed between the two measurement times for the other attributes. Furthermore, the species specific regeneration frequency was affected by a significant reduction in seedling and saplings in 2014. However, tree percentages increased in 1st and 3rd quality grade classes, whereas it decreased 2nd class andd remained unchanged in 4th class. All in all, the results showed that the average values of quantitative and partlyy qualitative characteristics were not far from favorable conditions during the period of forestry plan, which indicated the conducted silvicultural practices served the defined goals of the close to nature forestry method.

Survey and monitoring of forest areas in which silvicultural interventions were conducted over at least one decade and comparing of quantitative and qualitative characteristics of them with untouched stands could be a useful guide for planning the next interventions considering the goals of close to nature silviculture. Present research was carried out with the aim of studying the natural structure of oriental beech stands with emphasis on stem number in the first diameter class in order to obtain continued stability and adopting an appropriate silvicultural method in accordance with their structure and optimal management by better recognition of them especially surveying number of the trees in first diameter class (n10) as a sign of long-term sustainability of stands and planning for existence of enough numbers of this class in forest areas.
This study aims to compare the silvicultural characteristics between compartments 127 (managed) and 128 (unmanaged=control) in district one of Jahan-nama water catchment, Gorgan. Five sample plots, each one ha (100 x 100m), were laid out in each compartment, a total of 10ha, in random-systematic network.All of the trees with diameters above 5 centimetres inside the sample plots were harvested using the one hundred percent inventory method. To study the structure and regeneration rate of the stand, transects with a size of 100×10 metres were embedded in the middle of each plot in two directions. The heights of all existing trees in each compartment and other features such as canopy cover and quality of tree trunks were recorded in the related forms. Then, a 3×3 m micro plot was inserted inside each transect in 15m distances in order to study regeneration and the seedlings.
The results showed statistically significant differences of mean diameter and height of trees as well as regeneration number between the two studies compartments. Also, the frequency of stem number in the first diameter class (N10) of the managed compartment was 7 times higher than that of the control compartment. This difference was statistically significant. The results show that the highest difference in diameter classes is less than 15 cm, such that frequency of oriental beech species in the first diameter class (N10) in managed compartment is 4.5 times more than reserve compartment.
Hence, the silvicultural interventions have led the managed stand to uneven-aged structure with sufficient stem number in N10, that with executing of silvicultural tending we could obtain sustainable stands. It will bring continued stability of forest stands with a wide presence of climax species (such as oriental beech) in the long term.

In order to determine the most appropriate amount of exposure and irrigation for the breeding of wild pistachio (Pistacia atlantica zohary) seed plants in the nursery, the effect of three light treatments (100, 50, and 20%) with four replications (0, two, five, and ten days irrigation) on seed plants was explored in the first year of planting, in a split-plot design in which light comprised the main plot and the irrigation treatments formed the sub-plots. The results obtained at the end of a growing season indicated that the impact of different light treatments was significant for the seed germination (at 5% level), the height and diameter growth traits, and the number of seedling, subsidiary branches, and leaves (scattered at 1% level). The effect of different irrigation treatments on germination traits, subsidiary branches, leaves, the collar diameter (at 1% level), and the growth height (at 5% level) was significant. Furthermore, the interaction effect of light and irrigation was significant for the buds, subsidiary branches, and diameter and height growth yields (at 1% level) as well as the number of leaves (at 5% level). The maximum number of buds, leaves, subsidiary branches, and diameter and height growth belonged to 100% light and two days irrigation treatments. The study was carried out on wild pistachio seed plants during the first year of growth. To monitor the changes in the results, the study should continue until the seedlings are planted in the field.

Deadwood is commonly known as an essential structural and functional element in forest communities. Thus it is important to understand its role and natural dynamics to improve the forest management strategies in both managed and unmanaged forests. This study analyzed both qualitative and quantitative characteristics of deadwoods asindicatorsof stand developmental stages in the unmanaged forests of Kheiroud in Mazandaran province, northern Iran. Three sample plots were established in the initial, optimal and decay stages, in which attributes such as diameter at breast height, height of all standing and dead trees as well as the decomposition stage of dead trees were recorded. Results showed differencesin the amount of deadwood per ha as well as in volume, type andsizeofthe coarse woody debris (CWD) in all the three stages. The frequency of snags was higher than logs in initial and decay stages, whereasthe proportion of logs was greater than snags in the optimal stage. Moreover, maximum and minimum volume ofthe CWD was observed in the initial and optimal stages. Amongst the species, beech returned the highest number and volume of deadwood in all three stages. In addition, the entire deadwood showed diameter

In this study, the effect of water salinity accompanied by organic and inorganic fertilizer was examined on the growth, quantitative characteristics and photosynthetic pigments in borage plants. The experimental was split plot based on complete block design with three replicates. Treatments were two irrigation sources: irrigation with fresh and saline water (EC: 4.18 dS m-1) as the main plots, and four fertilization systems: application of NPK at 80:40:30 kg ha-1, 40 t ha-1 of manure, NPK at 40:20:15 kg ha-1 plus 20 ton of manure ha-1 and no soil fertility as sub-plot. The experiment was conducted in 2012 at the Zabol University Research Farm, Zabol, Iran. The results showed that irrigation with saline water significantly reduced plant height, flowering stem height, inflorescence height, number of flowers per inflorescence, number of branches, content of chlorophyll and carotenoid. Application of fertilizer significantly increased all studied traits compared with the control. Combination of organic and inorganic fertilizer was more effective than sole application and increased inflorescence height, number of lateral branches, number of flowers per inflorescence, chlorophyll a, total chlorophyll and carotenoids by 19.4, 30.9, 31.5, 25.6, 24.8 and 25.3 percent over control, respectively. Interaction of water quality and fertilization was significant on plant height, inflorescence height, chlorophyll b, plant dry weight and flowering shoot weight and fertilization protect economic yield against saline water. It is concluded that fertilization, especially combination of organic and inorganic fertilizer, could be recommended for economical production of borage under saline condition in Zabol.

Yield increasing and also the introduction of new varieties of cotton is one of the main goals of researchers. The important goal of this research was recognition of superior varieties in terms of yield. New and cultivated cotton genotypes including new varieties B557, T3, T2, SB35 and commercial cultivars like Moghan, Golestan and Sahel were evaluated in a randomized complete block design in Karkandeh Cotton Research Station. The results showed that T2 variety with 2160 kg/ha had the highest yield and SB35 variety with 1806 kg/ha had the lowest yield. Variety of B-557 with 75.8 % and varieties of T2 and T3 with 73.5 and 74.6 % were the earliest genotypes, respectively. Late maturity among varieties belonged to Armaghan and SB35 varieties with 53.8 and 55.7 %, respectively. The highest and lowest bolls weight were related to Golestan cultivar with 183.2g and T3 genotype with 153/8g, respectively

Study of Cypress (C. sempervirens) trees in Zagros region of Iran is of vital importance due to its rare occurrence in the region as well as its functional، socioeconomic and ecological values. In this study، quantitative and qualitative characteristics of this species have been studied across on of its native habitats in Khuzistan province. To accomplish the study، a portion of Cypress – dominated area of 100 ha near Baghmalek was inventoried by full callipering. One-way ANOVA and Duncan test were used to compare the means of Diameter at Breast Height (DBH)، height and percentage of canopy. Similar ANOVA was used to quantify the effect of humidity and aspect on seedlings height. The tests indicated a significant difference between means of DBH، height and percentage of canopy in all geographical aspects. The Duncan tests also showed a significant difference between Western slopes and a range of others (South، South-West، South-East and North-West) for DBH. It also indicated the South-East aspect to be significantly different that all other aspects for height. For the percentage of canopy، South-Eastern and Western aspects were different than South ern and North-Western aspects. Furthermore، the qualitative analysis showed that 53. 1%، 34. 6%، and 12. 21% of C. sempervirens trees were of 4، 3، 2 quality degree، respectively. The Univariate test for the effect of humidity and aspect on the height of seedlings showed a significant effect. However، aspect as well as their interactions did not indicate any significance. As a conclusion، this study suggests a biological enhancement of soil moisture which in turn improves the natural regeneration of Cypress trees in this and similar areas.

Self-incompatibility is one of the most important difficulties in almond production which reduce fruit set drastically and makes orchard management difficult. Therefore, breeding of almond to produce self-compatible genotypes is very important. In this research, level of self compatibility in 50 selected genotypes of different crosses was studied using linked markers through PCR analysis and fruit set. Result showed that 31 genotypes had band with length of 450 bp which were identified as self-compatible genotypes. Study of fruit set after self pollination showed that 31 genotypes with fruit set more 5% identified as self-compatible. The most fruit set after self pollination observed in genotypes number 42, 45 and 24 to rate 26.94, 25.1 and 25 percentages, respectively. Comparing fruit set percentages after self pollination with open pollination showed that selfing reduced fruit set percentages but the decrease of the fruit set in some genotypes was very low. The result of investigation of fruit qualitative and quantitative characteristics showed, in total, very self compatible genotype number 24, was better than other genotypes. This genotype produced fruit, nut and kernel with medium size. Fruit, nut and kernel weight was 10.80, 3.98 and 1.41 g, respectively. Nut and kernel color of this genotype was bright and its kernel taste was sweet. The beginning of flowering in this genotype was later than other genotypes and fruit harvest dater was sooner than other genotypes. In total in this research, genotype number 24 identified as suitable genotype.

In order to study the effect of CPPU growth regulator on qualitative characteristics of cut rose (Rosa hybrida cv. Avalanche)، an experiment was performed as factorial، based on a completely randomized design، with four replications. In this experiment، the first factor included four concentrations of CPPU (0، 25، 50 and 100 mg/L) and the second factor was two application positions of CPPU (on the stem، and on the bud with a half cut ring 1 cm above the bud). The results showed that bud break، flowering time، length and diameter of flower shoot، flower diameter، number of internodes and fresh and dry weight of flowering stem were significantly (P< 0. 01) affected by CPPU treatments. The earliest bud break and flowering، longest stem، highest shoot and flower diameter and the highest stem fresh and dry weight were observed in the 50 mg/L CPPU treatment. However، application position of CPPU on the stem did not show any significant effect on the studied traits. Based on the results of this experiment، using CPPU growth regulator can increase growth of basal buds and enhance qualitative properties of the cut roses.

In order to study the qualitative، quantitative characteristics of a pure common Populus alba stand in Polkalleh & a mixed stand of Populus alba & Populus nigra in Karchegan، two 30-year-old stands were selected with a plantation interval (spacing) of 2. 5 × 1. 5 m in each of which 30 pcs of 2 are samples were randomly selected. In each sample pc all the trees diameters were measured using a diameter gage tape and relevant heights were measured using a Sonto gradiometer. The measurement results of quantitative variables showed that average diameter for the pure Populus alba stand 26. 36 cm، for the mixed stand of Populus alba & Populus nigra 22. 02 cm، for the Populus alba trees in the mixed stand 22. 44 cm and for the Populus nigra trees in the mixed stand 20. 98 cm obtained. Also the average height for the pure Populus alba stand 23. 09 m، for the mixed stand of Populus alba & Populus nigra 21. 05 m، for the Populus alba trees in the mixed stand 21. 31 m and for the Populus nigra in the mixed stand 20. 42 m calculated. Average volume for the pure Populus alba stand 679. 06 m3/hectare and for the mixed stand of Populus alba & Populus nigra 679. 06 m3/hectare obtained of which 323/81 m3/hectare for the Populus alba trees and 106. 24 m3/hectare for the Populus nigra trees respectively. According to the results، quantitative and qualitative characteristics of pure Populus alba stand is in a better situation than than the mixed stand of Populus alba & Populus nigra.

The main objective of this study was estimation of three forest biophysical properties including volume, basal area and number per hectare using SPOT-HRG data in district 1 Darabkola’s forest. Images were orthorectified to reduce relief displacement errors. Different synthetic bands were generated trough principal component analysis and suitable vegetation indices were created by rationing. After take territorial information, accomplished calculation volume, basal area and number per hectare values in sample plat. Since analyze normalized data, evaluating correlation between territorial and spectral by linear regression. Cross validation getting best correlation model investigating by some sample plat and by relevant evaluation criterions. For volume estimation, results of this study showed that linear combination of NIR and SWIR bands by adjusted determination coefficient 74.5% and root mean square relative error 77.1 m /ha were better predictors than other combination. For basal area estimation, linear combination

This study aimed to determine the effect of physiographic factors (slope، aspect and altitude) on quantitative characteristics of Persian Oak (Quercus brantii Lindl) in forests of midlle Zagros. In this study in forests of the Abdanan city if Ilam province and regional functions area were approximately 150 ha، 134 sample plots of rectangular shape with dimensions 40 * 50 m to the systematic – random method in a network with dimensions 100 * 100 m using and species characteristics، dbh، crown diameter، heigh of trees and physiographic sample plot (slope، aspect and altitude) were recorded. Results showed that the effect of physiographic factors on dbh of trees was not significant. The aspect and altitude on the characteristics size canopy of tree، basal area per ha and number of ha has a significant impact. Among the physiographic factors aspect have a significant impact on trees height. This study can conserved areas that Oak species with quantitative characteristics better and special attention to areas that are being destroyed، to be effective.

In order to investigate the effect of planting date on qualitative and quantitative characteristics of medicinal plant of black cumin was investigated in a split plot experiment based on randomized complete block design with four replications at Khomeini – shahr, in the province of Isfahan, Iran, during growing season of 2009-2010. In this study India and Isfahan populations were assigned to main plots and four sowing date (16 Nov, 16 Dec, 6 Mar and 4 Apr) to sub plots. The results indicated that planting date, populations and their interactions had significant effect on most of the traits measured. It was also observed that the two populations were significantly different in phenological, morphological and qualitative characteristics. Isfahan population due to its compatibility to the climate of Isfahan produced highest seed yield and oil percent than the Indian population at 6 Mar. planting date. Also, late planting date resulted in reduced values of most of the traits related to yield and yield components. It was also observed that highest dry matter, manganese, sodium, calcium and zinc contents were obtained from the Isfahan and highest content of ash, potassium, phosphorus, magnesium, copper and iron from Indian populations. It may conclude that if it is aimed to have higher seed yield and oil percent it is better to plant Isfahan population at the second and third and Indian population at the third planting dates.