Iranian Journal of Forest and Poplar Research
Year:2011 | Volume:19 | Issue:3 (45)|Papers Count:18

The saplings of four well known urban trees, namely: Acer negundo, Fraxinus angustifolia, Robinia pseudoacacia and Thuja orientalis were regularly watered by 0, 40, 80, 120 and 160 milimole per liter NaCl, during a three-month period in growing season and some of their quantitative and physiological characteristics of growth and development were measured, immediately after pot-planting in greenhouse conditions. In general, saplings of Robinia demonstrated better survival characteristics, as the results indicated. It was the same story for increasing in diameter growth and weight of stem: a decline in these factors for Acer (from 120 and 40 mMol/l) and Fraxinus (from 40 mMol/l), respectively and no change in Robinia. Significant decrease in leaf sodium and increase in leaf potassium contents were recorded only in Robinia. Other results were rather different or controversial. As salt become more accumulated, for example, the least height increasing was observed in Acer, along with Thuja, or the ratio of Na+/K+ raised from 120 and 40 mMol/l for Fraxinus and Thuja, respectively. The leaf calcium content was increased only in Acer (from 80 mMol/l), and no change was observed in leaf magnesium content. In general, for all broadleaved species, saltier water was associated with more leaf decoloration, as expected.

In this trial, 14 clones of Populus nigra were studied during 2001-2008 in Sanandaj, Kurdistan province. Planting of cuttings were accomplished in early March of 2000 and transplanting and planting of saplings were conducted in early April of 2001 with space of 3 m × 3 m based on the Randomized Complete Block Design (RCBD) with 3 replications. Each plot contains 25 saplings that were planted as 5×5 (9 saplings as main and 16 as buffer) and some morphological and qualitative characteristics were evaluated every year. Results showed that the first and second years after planting (2000 and 2001) were "establishing phase" of saplings, which showed a very low portion of diameter at breast height (DBH), tree height (H) and wood volume (V) increment. Total means of DBH, H and V in the sixth year of experiment (2007) as final year of the study were 15.2 cm, 9.82 m and 107.55 m³/ha, respectively. Analysis of variance showed significant differences at p£0.01 among poplar clones for all studied traits. This provides a suitable background for selection of superior clones. The combined analysis of variance revealed significant differences of clone × year interaction variance, indicating that clones responses to years conditions were different. According to the comparisons of means with Duncan’s test (p£0.01), clones of P.n. 56.52, P.n. 56.75, P.n.62.140, and P.n. 63.135 were superior clones among the studied clones with DBH of 17.9, 18.3, 15.7 and 16.0 cm, tree height of 10.61, 9.94, 10.53 and 10.01 m, wood volume (V) at the end of the experiment 153.68, 148.79, 119.87 and 118.19 m³/ha, mean annual volume growth of 25.61, 24.80, 19.98 and 19.70 m³/ha/y and mortality percentage due to drought stress in 2007 about 25.93%, 29.63%, 40.74% and 48.15%, respectively. Superior clones showed moderate to good vitality, mainly safe from a contamination by pests point (in the normal conditions of 2000-2007) and straight stems. The wood yield of superior clones was about 1.1-1.4 times more than clone’s average and 1.3-1.6 times more than 2 standard clones (P.n.Saghez and P.n.Grizah) averages. Order of superior clones in the third to the seventh years of trial was almost similar. Therefore, decreasing of study time from 10 to 5 years could be possible in elimination trails. The occurred drought stress in 2007 resulted in (i) decreasing of growth of all clones and changing of order of superior clones, (ii) attacking of Melanophylla picta to field due to poor growth as secondary stress and (iii) early fall in the all clones. Because of various environmental stresses in Iran, we recommend that the stress effects (mainly drought stress) and clone tolerance as important parameters in clone selection and breeding programs should be evaluated in the future studies of clone adaptation.

Oriental Beech (Fagus orientalis Lipsky) is one of the most important forest tree species in the north of Iran. This study aimed to investigate the morphological and quantitative characteristics of mature beech trees (d.b.h.>1 m) in two forest regions, located at Kheiroud district in Mazandaran province and at Sistan district in Guilan province. In each region, 33 trees were selected and some morphological and quantitative characteristics were studied. Results showed that frequency of forked crown shape has significant difference (a=0.01) in two regions and in Kheiroud was more than Sistan. Frequency of spiral growth and Chinese beard node didn’t show significant difference in two regions. The differences of crown height, tree height (a=0.05) and trunk length (a=0.01) were significant in the two regions. Crown height and tree height in Kheiroud were higher than in Sistan, but trunk height in Sistan was higher than in Kheiroud. Slenderness coefficient didn’t show any significant difference in two regions.

In order to study the above ground biomass of three leguminous species in different planting (pure and mixed) for biological sand dune fixation, this investigation was carried out on sandy hills of Khuzestan province, located in southwest of Iran. This experiment was conducted in 1999 under rain fed condition and split plots method in frame of Randomized Complete Blocks Design with three replicates. The main treatments consisted of three levels of spacing (3 m×3 m, 4 m×4 m and 5 m×5 m), and the secondary treatments consisted of three species (Prosopis juliflora, Acacia victoriae and A. farensiana) in form of pure and mixed (50%) in six levels. The measured characteristic was biomass (total, forage and woody). After seven years, the data were analyzed, using Duncan test and analysis of variance (ANOVA). The results showed that the maximum total woody biomass achieved by P. juliflora in pure plantation in all three planting spaces. The maximum forage biomass belonged to A. victoriae with 1719.67 kg/ha in 3 m×3 m planting space, and the least belonged to A. farnesiana with 191.33 kg/ha in 5×5 m spacing, respectively.

In order to study the influence of some ecological factors on distribution of yew tree and its regeneration in Arasbaran forests, two habitats of yew including Kalaleh in Ilganechay and Kooran in Horand regions were studied. To provide appropriate distribution of sample plots, three altitudinal levels were selected for each region in each habitat (1100-1200, 1200-1300 and 1300-1400 m.a.s.l.) and on this basis, 43 circle sample plots, each 1000 m2, were laid out by selective sampling method. Also micro sample plots, each 100 m2, were laid out within the macro sample plots to study the regeneration. Some sample characteristics including altitude, slope gradient, aspect, crown cover, diameter at breast height and total height of all trees were recorded. Results indicated that yew trees prefer 1200 to 1300 m.a.s.l., north aspects with 51-75% slope gradient. Our study reveals that yew regeneration in undisturbed habitat (Kalaleh) with 53% seed origin seedlings were more in compare to the disturbed habitat (Kooran) with only 35% seed origin seedlings.

In this study, hardwood cuttings of Populus caspica Bornm. were collected from three origins of Golestan (sub-humid), Mazandaran (humid) and Guilan (very humid) regions and their transplants were planted in nursery of Koloudeh, Amol, north of Iran. In July 2009, seedlings were subjected to flooding stress for 150 days. Experiment was carried out as Completely Randomized Block Design in four replications. Results showed that among control seedlings, survival rate of origins varied between 93.7 and 100%. Golestan origin showed maximum height and collar diameter increment and Guilan origin indicated highest root biomass, total biomass and leaf area. In flooded conditions, survival did not differ among the origins and it always was higher than 93.7%. Likewise, no significant differences of height and collar diameter increment, root biomass, and total biomass were found among the origins. Generally, although the values in most of attributes of seedlings were smaller under flooding than control, seedlings of three origins displayed relatively good response to flooding. This study confirms that Populus caspica is a good flood-tolerant species and thus, it can be used for planting in wetlands, riversides and flooded areas of northern Iran.

Saxaul (Haloxylon ammodenderon C.A.Mey) communities are important part of vegetation in central deserts of Iran. Due to their protective and conservative role specially in providing habitat for wildlife and soil erosion control, any research about them has an outstanding worth. In this research, primarily a 10 ha shrub-land of Saxaul in Siahkooh of Yazd was selected and fully callipered in 30×30 meters quadrates. In each quadrate, species, crown diameters, distance and azimuth from left downside angle were measured. Stem map of all plants was drawn by ArcMap software. Then spatial pattern of plants was determined by three methods: i) Nearest Neighbor, ii) Ripley’s K- function and iii) mean square method which is a kind of quadrat variance methods. Results of Nearest Neighbor method showed that, spatial pattern of plants is random. Other methods showed that spatial pattern is random, but by increasing the distance over 10 meters, the pattern tended to be clumped. Overall, the spatial pattern of Saxaul was random and tended to be clumped by increasing the distance. It seems that homogenous site conditions are the most important causes of random pattern for Saxaul species in small scale. In larger scale (far from playa), Saxaul shrubs were more dense and the spatial pattern tended to be clumped.

In order to determine the role of non-wood forest products in livelihood of people, all of the forest dweller community in Kamyaran city (3725 family) was selected. Then 320 scattered families were picked out randomly by Morgan table and questionnaires were filled out. Results showed that the main source of fodder is trees and ground flora of forest, so livestock is completely dependent on forest. The study of the various income sources of local people showed that about 3.8% of the people’s income obtained from non-wood forest products, from which most of them belongs to Pistachio gum.

The goal of this study is presenting a proper method to improve the planning of forest roads network based on environmental, technical and economical considerations using GIS (Geographical Information System) and AHP (Analytical Hierarchy Process). Six different variants regarding to technical principles of roads network were designed using Pegger (an extension of ArcView software). Inner levels of layers were evaluated and ranked to get a proper environmental evaluation. The parameters were compared in pair-wise comparison in the context of AHP to develop map layers weights. Then weights, factors and constraints were entered to multi criteria evaluation (MCE) module to create final suitability map. All variants were evaluated from a technical stand of view in GIS using Backmond and Segebaden methods. In addition to six variants, in every 3 evaluation, we evaluate exiting plan in the study area as seventh variant. With review the result of environmental and technical evaluations of 7 variants, the variant with lowest total value in MCE with regard to technical principals was determined. This variant was evaluated economically, and then was checked by field reconnaissance. The obtained results showed that using GIS and AHP will improve planning methods.

Arasbaran forests is located in East Azarbayjan (North-West of Iran). Socio-economical problems of villagers cause increasingly destruction on exclusive biodiversity of these forests. A basic approach for preserving this forest is public cooperation in agroforestry activities for nonwood production using multipurpose trees such as cornelian cherry (Cornus mas L.). This species grows naturally in Arasbaran forests and a plenty amount of its fruit have annually been exploited in traditional manner. This study aims to assess the ecological requirement of cornelian cherry and the important factors which affect distribution of this species. For this purpose, 40 circular samples, each 300 m2 were selected in different aspects regarding to occurrence of Cornus mas in mature stands. Results showed that DBH and crown cover means in the north aspect were significantly more than those of other aspects and the proportion of cornelian cherry in mature stands counted for 4.5% of individuals recorded in the sample. North facing aspects have more seed-origin trees of cornelian cherry than coppice ones; on the contrary west facing aspects had more coppice trees. Regeneration of this species has the highest individuals in the sapling stage with 0-2.5 cm DBH. The mean number of total regeneration (including all species) per sample was 117.1 individuals in the Cornus mas sites.

Current research was conducted for evaluation of spacing impact on quantitative and qualitative characteristics of alder (Alnus subcordata C. A. Meyer) in fifteen years period (1999-2004) by Randomized Completely Block Design with 5 treatments based on spacing in three replications at Ladjim forest region. Spacing trial treatments included 1×1, 1×2, 2×2, 2×3 and 3×3 meter. Results indicated that mean dbh was significantly different in spacing treatments. Hence, dbh and height for spacing 1 m × 1 m and 1 m × 2 m were minimum, while in spacing 3 m × 3 m were maximum. The results showed that decreasing in spacing causes increasing in slenderness coefficient. Also the slenderness coefficient significantly varied with age and spacing of alder stands. Overall, in current study till fifteen years experiment of spacing trials, we are able to conclude that spacing 2 m × 3 m is suitable for reforestation in north of Iran based on maximum amounts of dbh, annual diameter increment, mean total height, annual height increment, and optimum slenderness coefficient.

In order to determine the most suitable water storage method and irrigation interval on growth characteristics of Acacia nilotica for using in afforestation, a split- plot experimental design with four replications was conducted in south of Sistan and Baluchestan province in Iran. The main factor was rain saving method with two levels (turkey nest and small soil dam), and the sub factor was irrigation intervals with three levels (10, 20 and 30 days intervals). Results of the experiment showed that Acacia nilotica is a suitable species for afforestation in Dashtyari region of Chabahar. The best irrigation period was 10-day interval, due to better survival rate and growth characteristics of Acacia nilotica than in other treatments. 20-day irrigation interval could be introduced for regions with scarcity of water. Two methods of rain water saving did not have any statistically significant effect on establishment of this species.

Introducing appropriate and applicable methods is an important step towards restoration of Zagros forests. In this study the possibility of rooting and propagation of sprouts of Manna oak was investigated by layering in soil. This study was conducted in Completely Random Design with four factors including soil type (forest soil and litter), super absorbent hydrogel (100 gr and 0 gr), IBA hormone (2000 ppm and 0 ppm) and pitcher irrigation (using earthen pot and disusing earthen pot). Overall, 16 treatments with three replications were prepared. The result of ANOVA test indicated that there are significant differences among treatments both in callus production and rooting. Callus production was observed in all of the treatments. In contrast, rooting was just observed in treatments treated by IBA. The highest proportion of callus production and rooting was observed in treatments with the best moisture conditions.

Populus caspica Bornm. is an endemic and fast growing tree distributed in northern Iran, considered as endangered species without proper sexual reproduction in natural conditions. In contrast to other poplar species, knowledge about regeneration of this species is little. The tree yearly disperse plentiful of short-lived tiny seeds that need the suitable conditions and substrates to germinate and grow. Usually, the required conditions are not available in its natural habitats. The study was carried out to consider the mentioned problem. Therefore, for mass production of seed-born seedlings and broadening genetic basis of the species, matured capsules were collected from 25 single trees, distributed at different sites in Golestan, Mazandaran, and Guilan provinces at early April 2010. Sixteen trees of the 25 trees produced suitable and enough seeds. After well sifting, 30 seeds of each tree were sown per pot at three different soil treatments including: i) only nursery soil, ii) combination of nursery soil and fine sand (wind shifting sands), and iii) only fine sand, as well as three light aspect treatments including: 1) Eastern aspect, 2) Southern aspect and 3) Western aspect for 16 provenances. The experiment design was factorial model based on Completely Randomized Block Design with three replications. Pots were kept in large basins and irrigation was done daily in basin and pots. Weed control was done at different dates during growing season. Height of all seedlings was recorded at the end of growing season. Results of analysis of variance showed significant differences among all of the sources of variance. Soil treatments caused 113, 57 and 0 centimeters in seedling height, respectively. Significant differences were observed among the mother trees based on their seedling height. The results indicated that the progenies of Zarringol 2, Zarringol 3, Kenesy and Golestan 4 trees revealed 111.4, 98.9, 98.9 and 94.3 centimeter in height, respectively as the longest one, so that 11 groups were specified among the 16 mother trees. Significant differences among the direction treatments were observed, so that the seedling height of 87.6, 87.3 and 81.4 centimeters were recorded for eastern, southern and western aspects, respectively. As a main result, the study showed significant differences for height in soil, mother trees and light aspect treatments. Therefore, mass seed-born seedling production for the species would be possible using the best treatments of the study.