Abouzar Heidari Safari Kouch, Freshteh Moradian Fard, Azita Eskandari, Teimour Rostami Shahraji,
Volume 2, Issue 1 (9-2015)
Abstract
Persian oak (Quercus brantii Lindl.) has a wide distribution in central Zagros forests and it is the prevalent species in this region. Considering the high volume of demolition and the importance of safekeeping of this jungle, investigation and knowing the structure and the situation of this forest from the qunatitative and qualitative aspects is necessary. This study accomplished to investigate the condition of the Iranian oaks (Quercus brantii Lindl.) forests from the qunatitativeand qualitative aspects of Bazoft district of Kouhrang township of Chahar Mahal and Bakhtiaris province. In this respect, 60 numbers of plots with 400 meter distance in a randomize systematic method established in the area. Then in the studding plots the quantitativecharacteristics of trees like: dbh, trees high, crown diameter measured and some characteristics like canopy percent and firewoods were estimated and registered. Also qunatitative marks from 1 to 4 were given to the trees and they were recorded and data were analyzed. The results shown that the jungle wasa non- coeval and it was sparse forest. Also, 81% of the region had 0-25% coverage. The most density and firewood volume was observedin northeast direction. Also,75% of the trees were inthe proper degrees of Succulence. The results of this study showed the average and a suitable situation of study area stands in comparison to the other regions of central Zagros forests.
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Amir Modaberi, Javad Soosani, Shyda Khosravi,
Volume 2, Issue 1 (9-2015)
Abstract
The main objective of this study was to estimate the effect of decline disturbance on diameter distribution of coppice oak trees in central Zagros region. For this purpose, two similar stands with equal areas (32ha) in central Zagros (Shorab in Lorestan province and Zarabin in Ilam province) were selected. Diameter at the breast height of declined trees was recorded before and after cutting using 100% inventory method. Following probability density functions (PDFs) Beta, Jonson, Weibull, Gamma, Normal and Log-normal were fitted to the data. The results of goodness of fit tests shown that Beta, Weibull and Jonson PDFs were fitted well to diameter of woody stems in Shorab but Jonson, Beta PDFs were much m ore suitable for Zarabin region. The difference of diameter at hight breast was studied in two stages of before and after declining by means of mortality PDF and using different PDFs. There was a big difference in diameter classes between before and after decline disturbance according to mortality distribution. There was no difference between before and after decline disturbance based upon statistical distribution fitting criteria. Outbreak of decline within this region had merely similar influences on all diameter classes, and as a result, it had not a significant effect on overall diameter fit.
Hossein Mirzaie-Nodoushan, Zahra Abravesh, . Mahdi Pourhashemi, Majid Hassani, Parisa Panahi,
Volume 2, Issue 2 (3-2016)
Abstract
Although Quercus brantii Lindl. has shown suitable genetic variation in Iran, which is required for a sustainable forest ecosystem, but during the last decade, it came across some difficulties which are considered as oak decline. This research investigated seedling characteristics of four plant populations of the Quercus brantii species to assess genetic potentials of the populations to base a cornerstone for complimentary studies. Seeds were collected on ten single trees for each of plant population located in Kurdistan, Lorestan, Ilam, and Fars provinces in Iran. Seeds were sown in pots at greenhouse conditions to produce at least 30 single progeny seedlings from each population with three replications were studied. Vegetative characteristics such as plant height, leaf length, leaf width, and plant vigor were studied on the single plants. Data were analyzed based on a double nested statistical model, and then the data were analyzed on each population separately. Results indicated significant differences between the studied populations based on seedling height and plant vigor. Plant within population, showing possible differences between the single trees within the populations, was also significant for seedling height, leaf length and leaf width. In population based analysis, the populations showed different behaviors, so as there was not significant effects between single plants in Kurdistan population for plant height and leaf traits; whereas, in Lorestan and Ilam populations significant effects for the mentioned traits were observed. Although the populations showed different characteristics at seedling stage, but it is sought that there are still enough genetic variability and the high heritability that might be used in future breeding projects.
Mehdi Heydari, Ali Mahdavi, Elham Jaferyan, Vahid Mirzaeizadeh,
Volume 2, Issue 2 (3-2016)
Abstract
Judas tree belongs to valuable species in Zagros forests. Nowadays, due to the special beauty of this species, it has received substantial attention in afforestation. In this regard, the improvement of seed germination is a suitable way to improve the quantity and quality of producing seedlings in nurseries and the establishment of forest plantation. In this study, the seed germination characteristics and seedling survival of Cercis griffithii in different soil treatments have been surveyed in the nursery of Aivan County in Ilam province. The experiment was set up as a randomized complete design with four treatments each contained 120 pots. Three seeds in plastic pots were sown in nursery soil (Control Control soil- cattle manure (5:1), Control soil- Litter (5:1) and Control soil- Cattle manure- Litter (5:1:1). According to the one-way ANOVA results, significant differences were observed between soil treatments in terms of germination rate, maximum, mean daily germination and germination energy, while there were no significant differences in other germination characteristics between soil treatments. The highest germination rate, maximum, mean daily germination and germination energy were observed in the treatment of Control soil- Cattle manure- Litter. In terms of time, seedling survival decreased from September to March. The results showed that there is a significant correlation between mean daily germination and different soil composition. In general, it can be concluded that germination and survival of Cercis griffithii can be improved using organic compounds in the nursery.
Ahmad Yaghoubi Farani, Marjan Sepahpanah, Farshad Parmozeh,
Volume 2, Issue 2 (3-2016)
Abstract
The purpose of this study was to identify the barriers of local peoples' participation in forest conservation plans. The research population included 240 Local rural households in Gilan – e – Gharb, Kermanshah. A number of 144 people were randomly selected using Morgan's sampling size table. A questionnaire was used as a main tool in this study. The content and face validity of the questionnaire was verified by a panel of experts. The reliability of the questionnaire estimated by Cranach's alpha coefficient (0.737). Factor analysis was used for finding the most important barriers. Four key factors were identified as the most important barriers in people participation programs in forest conservation plans. These factors were socio-cultural, economic, organizational and educational barriers.
Zeinab Javanmard, Masoud Tabari Kouchak Saraei, Fatemeh Ahmadloo,
Volume 2, Issue 2 (3-2016)
Abstract
In order to study the effect of storage temperature and hormonal concentration on stored seed germination and early growth of Pinus nigra var. caramanica, an experiment including 3 factors in the context of Complete Randomized Design (CRD) with 3 replications was carried out. The seeds were stored for three years at two temperature conditions (refrigerator temperature 4 ºC and room temperature 20-25 ºC). In this way, the seeds were soaked in gibberellin acid (GA3) and benzyl amino purine (BAP) at concentrations of 0, 50, 100, and 200 mg l-1 for 24 h and kept out in germinator (20 °C) for 40 days. In general, both hormonal solutions improved germination traits. The highest germination percentage, germination rate, germination energy, seedling length, seedling dry weight, and vigor index were obtained in refrigerator temperature and at concentrations of 200 mg l-1 GA3 and 50 mg l-1 BAP, and in room temperature at 200 mg l-1 BAP and 50 mg l-1 GA3. It is recommended that in nurseries of semi-arid and semi-humid regions, in the absence of refrigerator, the seeds of P. nigra var. caramanica would be better to store in the room temperature for three years.
Ismaeil Moradi Emamgheysi, Amir Eslam Bonyad, Mehrdad Mirzaei, Iraj Hasanzad Navroodi,
Volume 2, Issue 2 (3-2016)
Abstract
The aim of this research was study of tree species diversity in the Zagros forests of Iran that known as Ardal’s Chartagh protected forests. The total of the study area was 50 hectares. In this way 50 sample plots (circular shape with 1000m2) were measured based on systematic-random sampling method. In each plot species, DBH, species and number of trees were measured and recorded. To estimate of the tree species diversity, Shannon-Wiener, Simpson, Mc Arthur’s N1 and Hill’s N2 indices and for calculation of evenness and species richness Wilson- Smith’s and Margalef indices were used respectively. Also species importance value (SIV) was calculated. The results showed that there are 7 tree species in the study area including Fraxinus rotundifolia Mill., Juniperus polycarpos C. Koch, Cerasus mahaleb (L.) Mill., Quercus brantii var. persica, Pistacia mutica Fischer, Acer monspessulanum subsp. cinerascens and Salix persica Boiss.. Values of Shannon-Wiener, Simpson, Mc Arthur’s N1 and Hill’s N2 indices are 1.23, 0.58, 2.40 and 2.16. Also Wilson- Smith’s and Margalef indices showed that the values of richness and evenness are about 0.84 and 0.77. The results of SIV showed that the highest value of SIV belonged to the Fraxinus rotundifolia Mill. (188.63%) and the lowest value was due to Salix persica Boiss (17.59%). Therefore, conservation of forest stands might be suggested as a suitable approach for increasing plant diversity.
Sabrieh Moradi , Roghayeh Zolfaghari ,
Volume 2, Issue 2 (3-2016)
Abstract
Morphological characteristics of individuals are due to hereditary and environmental factors. Regarding to the importance of leaf morphology in systematics investigations and bearing up the effects of environmental variations, especially altitudinal variations on these traits, the differentiation feasibility of brant oak in a restricted altitudinal gradient is investigated. A total number of 400 leaves from 40 individual ramets in Armarde, in an altitudinal ranges from 1580 to 1844 meters above sea level were sampled and 29 quantitative and qualitative traits were measured. The results revealed that the number of teeth and the shape of leaf at lower altitudes are lesser than higher altitudes. Also, leaf base angle has a negative and significant correlation with the altitude. In two altitudinal classes, the shape of leaf tip and the angle of midrib and vein, showed the lowest plasticity and coefficient of variation with respect to environmental conditions. Ramets were classified in three different classes based on cluster analysis and the separator traits were the maximum leaf width, leaf area and sinusoidal angle. Considering the fact that the separator traits would not showed any significant association with altitude, it seems that some variations might be likely due to physiological response of leaves to environmental variations. However, it's more likely that the occurrence of inter and intra specific hybridization between brant´s oak species would culminated in separation of the individuals.
Ahmad Hossieni , Syyed Mohsen Hossieni ,
Volume 3, Issue 1 (9-2016)
Abstract
Oak decline is a complex phenomenon that oak forests are faced with it across the world and Iran. Shalam forested area located in north of Ilam province was selectedto determine the role of topographicand some edaphic factors in tree mortality happened in Persian oak forests. The study region was divided into 20 homogeneous topographic units. Within each homogeneousunit,three 0.1-haplots were randomly-systematically established for measuring the rate of tree mortality and oneprofile was prepared for characterization ofsome physical and chemical soil characteristics (texture, moisture content, TNV%, OC% and N for each soil layer, and soil depth). In each plot,diameter at breast height (DBH), maximum and minimum crown diameters, crown dieback percent, origination and form of trees and shrubs for all species and site variables weremeasured. Results showed that 15.7% of forest stock had reduced while 97.65% of it belonged to Persian oak species. The results of multiple linear regression and RDA showed that tree mortality was significantly affected by elevation and aspect, but not by slope. The highestrate of tree mortality was observedin high elevation and south and west aspects. Also the results of multiple linear regression and RDA showed that tree mortality was significantly affected by soil depth and texture. So, the highestrate of tree mortality was observed in soils with less depth, less sand% and more silt%. It was concluded that topography and soil have effective role in tree mortality and its expansion across Zagros forests. Identifying the critical conditions in terms of topography and soil in these forests can help and be useful in the management of tree dieback.
Anahita Rashtian, Afagh Tabandeh Saravi, Somaya Naseh Dehabanda,
Volume 3, Issue 1 (9-2016)
Abstract
Salinity is one of environmental stresses in the world and especially in arid lands and desert that reduces production of plants and it is important to choose salt-resistant plants in all life stages, especially germination. The aim of this study was to investigate the effect of seed source (provenance (on germination and morphological traits of Amygdalus elaegnifolia saplings undersalt stress. The experiment was carried out as factorial in completely randomized design withthree replicates. Seed source (FereydonShahr, Kazeron and Semirom) and salinity treatment withfour levels (0, 1.5, 3 and 5 dSm-1) using NaCl were considered as first and second factors, respectively. The measured variables were germination percentage, germination rate, vigor index, shoot length, radicle length, shoot wet weight, radicle wet weight, shoot dry weight, radicle dry weight, total leaf number, and radicle length/shoot length. The results of analysis of variance and mean comparison showed that salinity made significant differences in most of the investigated traits of Amygdalus elaegnifolia. In the control treatment of salinity, significant differences were found among the studied seed sources but the effect of seed sources was not significant in the other levels of salinity. In general, Fereydunshahr was the best of all studied provenances in non-saline conditions (control treatment).
Vahid Mirzaei Zadeh, Maryam Niknejad, Mehdi Haydari,
Volume 3, Issue 1 (9-2016)
Abstract
The importance of vegetation as a dynamic factor affecting the biological conditions requires that a detailed qualitative and quantitative information about its changes be prepared in short intervals. In this study, in order to monitor and predict vegetation density in Venet watershed in Ilam province the Normalized difference vegetation index (NDVI) and Landsat images from 1988 and 2007 was used and vegetation density maps in three classes without canopy cover, thinned and dense canopy covers were prepared. Comparing the extent of vegetation density classes indicated that the extent of bare soil areas have increased as 1158/837 hectares while the extent of thinned and dense canopy covers 360/8277 and 797/9544 hectares respectively has been reduced. Assessing changes in vegetation density showed that from the classes with thinned and dense canopy covers as 1233/4828 and 210/4539 ha respectively have become no vegetation cover class. Also as 246 /2742 and 38 /8255 hectares of the bare soil areas have been converted to thinned and dense canopy cover classes respectively. Using Markov models and automated cells to predict changes in vegetation density showed that the highest and lowest probability of transition to no vegetation cover lands has been seen respectively in thinned (0.5059) and dense canopy cover (0.1023) lands. Finally, assuming a continuation of current trends, watershed vegetation density map of the target for 2020 was forecast. This map shows in the near future the land without vegetation cover will devote itself about 87 percent of this region.
Seyyed Majed Hesami, Saeiid Davazdahemami,
Volume 3, Issue 1 (9-2016)
Abstract
Phenology studies can be appliedin sustainable management, protection, rehabilitation, development, and utilization of forest resources. In this study, the phenology of Persian oak was investigated in three forested areas of Mamasani, Dasht-e-Arjan and Kamfirouz with 2300 m,2100 m,1800 m altitude, respectively in south –west and north of Fars province, Iran. In each area, ninetrees were visited repeatedlyat different times in different seasons during 5 years (1998-2002) and the observed characteristics were recorded. The results showed the stages of growth were completely different at the threementioned areas. The shoots sprouted up in the second week of March to the first week of April. The full leaf formation happened in the second week of April to the fourth week of April. The early flowers appeared in the second week of March to the fourth week April. Pollination occurred in the third week of March to the third week in April. The leaves began to fall in the fourth week of October to the fourth week of December. So characteristics of phenology in Persian oak were affected by climate and environmental factors.
Farhad Ghasemi Aghbash, Geshin Allah Veisi, Vahid Hosseini,
Volume 3, Issue 1 (9-2016)
Abstract
Litter decomposition is the most important way of nutrient entering to soil and soil nutrient availability is highly related to dynamics of nutrients and litter decomposition in the forest ecosystems. This study aimed to evaluate the dynamics of nutrients and litter decomposition in the northern Zagros forests using litterbag technique for 180 days in the Khul Hoare forests located in Baneh city. The litter bags were collected at intervals of 30, 60, 120 and 180 days and the rate of leaf litter decomposition and chemical compounds such as nitrogen, carbon, phosphorus, potassium and calcium were measured. The results showed there was no significant correlation between the rate of decomposition and the initial composition of nutrients and also C: N and C: P ratios. Due to the qualification of leaf litter based on the amount of nitrogen in this study, the average amount of nitrogen in Quercus libani was 1.37%. So Lebanon oak can be classified in the average group and it can be considered as a soil improver species. In the studied litter, phosphorus and nitrogen had a similar performance and their concentration increased over time (7.27 and 30.38 mg/g respectively). While concentration of elements such as calcium, potassium and magnesium was decreased. The nutrient concentration of Quercus libani leaf litter was Ca>N>P>K> Mg.
Asghar Mosleh Arani, Mohamad Hossein Molakhalili, Bahman Kiani,
Volume 3, Issue 1 (9-2016)
Abstract
To investigate some effective causes of beetle attack to Amygdalus scoparia in Bagh Shadi Harat, Yazd 80 sampling plots were randomly selected. In each plot number of infected tree, percent of dryness for each tree, height, diameter at root collar and crown diameter of each tree, elevation, slope and aspect of each plot were measured or recorded. Results showed that beetle infection were positively correlated to dryness of Amygdalus scoparia, Loranthus Grewinkii and negatively to tree sprouting. Beetle infection were also positively correlated to density of Amygdalus scoparia, density and coverage of accompany species, number of dried Amygdalus scoparia and negatively to percentage of slop. It is concluded that beetles prefer habitat with denser and more coverage population of Amygdalus scoparia in flat area and on trees with less sprouting. Since the study area is an important conserved place in Yazd province, research to control the pest can be very important. Elimination of effected and old trees may limit growth of pests in this area.
Masoud Nejabat, Mohammadreza Negahdarsaber,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: Familiarity with the appropriate soil conditions for Pistacia atlantica leads to improve and develop forest vegetation cover in Zagros zone. The main aim of this research was investigate suitable soil characteristics ranges for natural growth of this species in Fars province.Materials and Methods: Field studies and soil sampling was done based on network sampling (20×20 km grid) in wild pistachio forests of Fars province with crucified pattern. The filed study showed mountain and hilly land are the main land types that pistachio species have placed on them. These land types include the displacement of rock, stone and gravel as high and low soil depth with moderate to severe water erosion.Results: Main physical and chemical properties measurement of soil samples showed that the only limiting growth factor has been the low soil depth. The low effective soil depth and light soil texture are the most important limiting factor on soil moisture storage ability (from rain). This deficiency, transition from drought or very dry periods (resulting from an undesirable distribution of rain) makes it difficult. Statistical analysis methods based on principal component analysis (PCA) and cluster analysis (CA) shows that wide ranges in soil characters, even up to about 40% differentiation in the measured properties do not make restrictions for pistachio Natural growth. Ecologically, Pistacia atlantica is a drought-tolerant plant. Wild pistachio (Pistacia atlantica) is one of the high resistance species in wide range of soil condition (soil characteristics) and this feature (desirable survival) make it favorite for Zagros forest rehabilitation.Conclusion: Land and grazing management (land use planning), along with watershed management practices can conserve and improve soil and environment of wild pistachio habitats of the Zagros forests.
Dr Farhad Ghasemi Aghbash, Sara Falahi,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: The recent movements opposing deforestation are indicative of the fact that in most programs carried out, less attention has been paid to the socio-economic status of the local people. In extensive deforestation, rural communities play a significant role. Therefore, this study examines the role of economic and social factors in the destruction of the forests of the Oulad Ghobad regions.Materials and methods: This research was carried out as a field study, using a questionnaire. The population comprised 398 families living on the outskirts of the Saman-e Orfi Forest in the Oulad Ghobad region. Out of this population, 150 families were randomly chosen, using Cochran’s sample size formula. Furthermore, 40 questionnaires were distributed among the officers of Lorestan Natural Resources Office. The validity and reliability of the questionnaire established by a pre-test and Cronbach's alpha were 0.83 for local people and 0.705 for officers, respectively.Results: The findings showed that from the viewpoints of both officers and local people, human factors (such as lack of agricultural lands, conversion of forests into agricultural lands by forest dwellers, poverty and and low income, and high unemployment rate) contribute more to deforestation, compared to natural factors (such as drought and forest fire). As for prioritizing human and natural factors contributing to deforestation, the results showed that according to local people, lack of agricultural lands (mean rank of 7.58), and according to officers, conversion of forests to agricultural lands by foresters (mean rank of 11.25) were the main contributing factors. In addition, the results showed that there was a significant negative relationship between income and the factors contributing to deforestation (P <0.001).
Conclusion: In general, the results showed that human factors have a significant effect on the deforestation of the Oulad Ghobad region of Koohdasht and the role of human factors is more conspicuous compared to natural factors.
Ahmad Hosseini, Seyed Mohsen Hosseini,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: Understanding the spatial pattern of tree species in their social life could have many applications from the standpoint of ecology and applied silviculture for their optimal management. For the purpose of studying the spatial pattern of Quercus brantii and Pistacia atlantica in relation to stand form and topographic factors, we selected the Manesht forested area in northern Ilam. Materials and methods: In this research, 75 sample plots (with 2000 m2 area) were chosen, using systematic random sampling method within the study area. The variables in the plots comprised the number of tree species and topographic factors. The dispersion indices of interest included Morisita, Sstandard Morisita, Green, Lioyd and variance to mean ratio. The calculation of quantitative indices, by running the relevant computational formulas, was performed by Ecological Methodology Software. In addition, in terms of accuracy, the efficiency of quantitative indices was studied and compared. Statistical analysis of data was carried out using SPSS Software. Results: The results showed that, for Q. brantii, the values of variance to mean ratio, Morisita and Lioyd indices and for P. atlantica, the values of Morisita, Green and Lioyd were higher in standard and coppice stands than the coppice and standard stands. For both species of Q. brantii and P. atlantica, all of the indices in question increased with increasing elevation, and the highest values of indices were obtained in 2100-2300 m a.s.l. For Q. brantii, the values of all of the indices increased with increasing slope, and the highest value was obtained in the slope class more than 60%. Moreover, for P. atlantica, the highest values of all indices were obtained in the slope class of 30-60%. The spatial pattern in classes of 0-30% and 30-60% was clumped and in more than 60%, it was regular. For Q. brantii, the values of all indices and for P. atlantica, the values of Morisita and Lioyd were the highest in the southern direction. The results of the precision study of the indices showed that for Q. brantii, the indices of Morisita and Standard Morisita and for P. atlantica, indices of Standard Morisita and Green had the highest precision. Conclusion: It was concluded that the value of dispersion indices (especially more accurate indices) varies by environmental factors and thus changes in values could be used in forest dynamic studies and the interpretation of changes in forests.
Morteza Rooki , Masoud Tabari Kouchaksaraei , Seyed Ehsan Sadati ,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: Mediterranean Cypress (Cupressus sempervirens var. fastigiata) is a native, evergreen species. Due to its various merits, particularly its wide use in parks and urban green spaces, it is of interest in most climatic regions of Iran, including Zagros provinces. Due to the poverty of soil and limitation in water sources, the production of seedlings of this species has become particularly problematic in some of these regions. By using rhizobacteria Pseudomonas fluorescens inoculation in soil, for the first time, the present study aims to determine the resistance and variations of growth characteristics of seedlings under water deficit conditions.Materials and methods: The experiment was conducted as a factorial, using a completely randomized design with two treatments (i.e., with rhizobacteria and without rhizobacteria), different watering levels (3, 6, 9 and 12 days) in three replicates. After 5 months, growth characteristics of seedlings were measured.Results: Increasing the watering period (water deficit) caused to significantly decrease the survival, diameter, shoot biomass and total biomass, so that all seedlings were died under 12-day watering level. In watering period of 9 days, survival was reduced to 49.83 percent. There was no significant difference in collar diameter, root length, root volume and root/shoot biomass with water deficit intensity. However, the survival rate, height growth, shoot biomass, root biomass, total biomass and seedling quality index were greater in seedlings inoculated with rhizobacteria, compared with those of non-inoculated seedlings.Conclusion: The seedlings of Mediterranean Cypress inoculated with Pseudomonas fluorescens rhizobacteria are able to tolerate the water deficit stress and increase their growth performance; however, under optimal conditions, the rhizobacteria inoculation has no positive effect on survival rate of the seedlings.
Somayeh Homayounfar , Roghaiyeh Zolfaghari , Payam Fayyaz ,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: Plant species with wide geographic ranges, exhibit high tolerance to cold stress. Trees in temperate regions must cope with freezing temperatures, especially in late autumn and winter. One of the mechanisms to tolerate cold stress is through decreasing photoperiod and temperature during acclimation. In addition, provenance of a species could be one of the main factors contributing to cold resistance. Therefore, in the present study, the effect of cold stress on physiological responses of Pistacia atlantica seedlings from three provenances was investigated in southern Zagros to select the most cold-resistant provenance.Material and methods: Seeds of three provenances, namely Margon, Noor Abad and Yasuj, from southern Zagros, were collected and planted in pots. After germination of seeds, induction of acclimation was carried out at two stages for four weeks. This was accomplished through the simulation of temperature and photoperiod of Yasuj region from September to November. Following that, the indexes of photosystem efficiency and chlorophyll content were measured. After each acclimation stage, leaves and stems of seedlings were exposed to three levels of temperature, +4°C (control), -20°C for one hour, and -20 for two hours. Then, relative water content (RWC) and electrolyte leakage (EL) of stems and leaves were measured. This study was conducted as a factorial with three factors of provenance (three levels), cold treatments (three levels) and acclimation (two levels), adopting a completely random design.Results: The results showed that EL increased with decreases in temperature and this increase was the highest in the case of the Noor Abad provenance. In addition, the stem RWC of Yasuj and Margoon provenances decreased in the second cold acclimation stage. Chlorophyll content, photosystem efficiency and electron transport rate were lower in Noor Abad provenance, compared with other two provenances. Moreover, except the electron transport rate, all fluorescence parameters significantly decreased during the cold acclimation. Conclusion: The results showed that measuring EL and fluorescence parameters could be a useful indicator for identifying cold-tolerant provenances. The seedlings of Noor Abad provenance exhibited the least and Margoon provenance showed the highest resistance to cold stress. This could be due to high altitude and cold climate of Margoon provenance.
Fatemeh Babazekri, Mehdi Nooripoor, Zeinab Sharifi,
Volume 3, Issue 2 (3-2017)
Abstract
Background and objectives: Forests and rangelands are the most important natural resources of a country. In addition, they have a special position in the ecosystem of the earth, and, thus, they play an essential role in soil conservation as well as climate moderation. However, serious and, sometimes irreparable, damage has been ocuured by both natural and man-made factors. One of the areas where degradation of rangelands and forests could clearly be recognized over the past years is the central District of the Dena County. Therefore, the purpose of the current study was to identify and analyze factors affecting the degradation of rangelands and forests in the central District of Dena County.Materials and methods: A mixed research method including qualitative and quantitative methods was used in two phases, using interview and questionnaire as instruments. In the first phase of the study, the population comprised the villagers and officers of the Department of Agriculture, Dena County and also the Provincial Department of Natural Resources in Kohgiluyeh and Boyer-Ahmad Province. In the second phase, the population consisted of the academic faculty members of local universities who were native and were familiar with the region. Snowball sampling technique was adopted in both phases of the study.Results: Factors affecting the degradation of rangelands and forests were identified in the first phase of the study. These factors comprised organizational factors (monitoring, supportive and administrative), infrastructural, socio-cultural, legal, economic and natural factors. Following that, in the second phase of the study, the participants were asked to rank the factors identified based on AHP procedure principles. The results showed that lack of grazing management in monitoring factors, less governmental support for natural resources in supportive factors, administrative corruption in administrative factors, road construction in infrastructural factors, poor cultural patterns in socio-cultural factors, lack of appropriate legal actions when faced with illegal possession in legal factors, rural poverty in economic factors, and finally drought in natural factors were the most important factors contributing to the problem of degradation.Conclusion: Finally, out of the recommendations made to prevent the degradation of forests and rangelands, one can mention the employment of native people to improve the management of rangelands and forests in areas of guarding and conservation affairs of natural resources. In addition, for the purpose of constructing roads, building power plants, etc. it is necessary to seek the expert advice of engineers with expertise in road construction, civil engineering and rural development.
