محمدرضا وهابی

Ammi visnaga L. is a medicinal and aromatic plant in the Apiaceae family. The essential oils of this plant have highly valuable aromatic compounds with valuable therapeutic and nutritional properties. Environmental stresses affect the quantity and quality of essential oils (EOs) in medicinal plants. This study was carried out to evaluate the independent and combined effects of salinity and drought stresses on EOs (%) and their chemical constituents in different organs of A. visnaga (seeds and head branches) under field conditions.

This study was carried out in the research farm of Isfahan University of Technology located in Lavark, Najafabad, using a split-plot design with three replications. Each replicate consisted of two rows (3 m long) of A. visnaga seeds. Different levels of salinity stress and drought stress were considered as main plots and subplots, respectively. Three levels of salinity stress [S1 (0 mM NaCl), S2 (80 mM NaCl), and S3 (80 mM NaCl)] and three drought stress levels based on soil depletion rate [D1: normal 50%, D2: moderate stress 60% and D3: severe stress 85%] were applied. Applying salt and drought stresses simultaneously started at the flowering stage (10%) and continued until the full maturity stage. After the full maturity stage of the plants, seed yield was measured. Then, the EOs extraction was done based on the Clevenger method in about 4 hours from head branches and seed samples for all studied treatments. The chemical constituents were identified using Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GC/MS) techniques.

The independent and combined stresses of drought and salinity caused a significant increase in EOs (%) of A.visnaga. The highest EOs in the head branch (1.26%) were detected under non-drought and medium salinity stress conditions (D1S1). The lowest EOs (0.25%) were observed under non-drought and non-salinity conditions (D1S1). The highest EOs (0.25%) in seed samples were observed under D2S2 conditions (moderate drought and salinity stress), but the least amount (0.12%) was found under D1S2 conditions (moderate salinity stress) and D1S3 (severe salinity stress). The analysis of essential EOs identified 25 compounds in both seeds and head branch samples. These compounds belong to six main chemical groups. The most and lowest compounds belonged to the groups of hydrocarbon monoterpenes and oxygenated diterpenes in both branches and seeds, respectively. Cembrene was identified as the main chemical compound in seed and head branch EOs. The lowest values for cembrene were reported as 23.32 % and 26.16% in seed and head branch EOs, respectively. The highest values for cembrene were reported as 33.31% and 36.62% in seed and head branch EOs under treatment. The compound 2-methyl-2-methylbutyl ester was identified as the second most abundant compound in the head branches and seeds of A. visnaga. The highest amount of this compound was observed in seed EOs (9.38%) under mild drought and mild salinity stress (D2S2), and the highest amount of this compound was observed in head branch EOs (18.5%) under mild drought stress (D2S1) conditions.

According to the study results, drought and salinity stress caused a quantitative and qualitative increase in A. visnaga EOs. Considering the climatic conditions of the arid and semi-arid regions of Iran and the consequent gradual salinization of soils, this plant can be considered a plant of choice in medicinal plant breeding programs, as well as goals related to the food and pharmaceutical industries.

The most important stresses in the world's agricultural lands, especially in Iran, are drought and salinity stresses, which are increasing in these days. In this study, the independent and combined effects of salinity and drought stresses were studied on different agronomic and biochemical traits of the medicinal plant of Ammi visnaga .The experimental design was performed as split plot based in a completely randomized block design with three replication. Drought stress treatments  based on soil depletion rate (normal 50%, moderate stress 60% and severe stress 85%) and  three salinity stress levels (normal, average stress: 80 mM and severe stress :100 mM were applied. The results of the present study showed that different levels of independent stresses and the combination of salinity and drought both caused a significant decrease in seed yield, seed weight and plant height and a significant increase in malondialdehyde content compared to the control treatment. In combined treatments, the changes in chlorophyll content did not show the same trend compared to the control treatment. In both drought and salinity stresses,there was a significant increase in the contents of total phenolics, total flavonols, total flavonoids, carotenoids, proline and antioxidant activity, compared to the control, in order to compensate  the negative effects of tensions. The lowest values for seed yield, plant height and the highest antioxidant activity were observed in the combined stress of severe drought and severe salinity.The highest content for total flavonols and carotenoid and the lowest value for malondialdehyde were observed in the combined stress of moderate drought and non salinity (D2S1). The highest contents of total phenolics (228.64 mg of gallic acid per gram of fresh leaves) and total flavonoids (120.62 mg of quercetin per gram of fresh leaves) were obtained in the combined stress of moderate salinity and severe drought (D3S2). The highest content of anthocyanin (0.12 μmol/g FW) in severe combined stress of salinity and drought (D3S3). These results showed the stimulating effects of these combined levels in the highest production of phenolics, flavonoids and anthocyanins compounds in this plant. Considering the significant increase of phenolic compounds in moderate and severe levels of drought and salinity stresses, its cultivation in lands affected by drought and salinity stress can be considered.

In the present study, the relationship between the distribution of Astragalus verus, climate, soil and topography in Isfahan province was investigated using the CART (Classification and Regression Trees) non-parametric regression. According to the vegetation types dominated by Astragalus verus, 287 sites were selected using stratified-random sampling and 106 presence points were recorded. Non-normally distributed soil variables were normalized according to the skewness type by data transformation. For variables that were not normalized by the data transformation, the inverse distance weighted and for normally distributed variables, kriging methods were used for mapping. To investigate the spatial continuity of these variables, the best variogram was selected. Using the principle component analysis (PCA) and correlation matrix, the most effective factors on distribution were clay percentage, mean temperature of the coldest (Bio11), and driest (Bio9) quarter, minimum temperature of the coldest month (Bio6), annual mean temperature (Bio1), saturated moisture and organic carbon, respectively. Model evaluation using replacement method and using independent data indicated high accuracy of the model. According to the optimum threshold of 0.41 and fuzzy-based habitat suitability map, the suitable habitat for the species was 34.5 % of the area. The results are used in sustainable rangeland management, conservation and their restoration.

This study was conducted to investigate the combined and independent effects of drought stress and copper on vegetative traits (root length, stem length, fresh and dry weight of seedling), essential oil content and copper accumulation in roots, shoots and distilled plant material of Fumaria parviflora Lam. In this study, different concentrations of copper (control, 50, 150, 300 and 400 mg /kg) and different levels of drought stress (control, 50% and 75% based on soil moisture percentage discharge) on seeds collected from two mineral regions in Kerman province (Askari and Rabar) and in each region four zones (Z1, Z2, Z3 and Z4) were used. The results showed that in all treatments, the concentration of 50 (mg / kg) copper without drought stress (control) led to the highest value in terms of vegetative traits.The highest percentage of essential oil (0.45) in the treatment with concentration 150 (mg / kg) of copper and medium drought stress in zone 3 of Askari copper mine and the highest concentration of copper in roots, shoots and distilled plant material in treatment with 400(mg /kg) copper and severe drought stress in zone 3 of Askari mine were observed. In this study, the Cu remained in the plant tissue during the distillation process and the concentration of copper in the distilled plant material was almost similar to the concentration of plant shoots before the distillation process. The best treatment for f. parviflora cultivation in terms of plant essential oil, 150 (mg / kg) copper and medium drought stress was evaluatedthese findings support the use of F. parviflora as an acceptable species for soils that are in moderation contaminated with copper. behaviors such as slow growth and severe decline in biomass at high concentrations of Cu, it is concluded that the F. parviflora cannot be a candidate species for the phytoremediation of copper contaminated soil.

Grazing is an effective factor on many aspects of plant species and communities. This anthropogenic factor, which became a destructive operant in Iran due to mismatch to range capacity, can affect the individuals of a plant species and thus, alter its spatial distribution. In the current study, the effect of short term exclosure on geographical distribution of two cool season grasses (Bromus tomentellus and Agropyron trichophorum) investigated using historical presence data. To do so, SRE modeling method (which is a presence-only model) was used to generate distribution maps before and after applying the exclosure. Presence coordinates of each species determined from 98 permanent exclosures. The number of B. tomentellus presence spots were 31 and 37 points before and after applying exclosures; respectively. The number of A. trichophorum presence spots were 16 and 25 points before and after applying exclosures; respectively. 19 bioclimatic variables used as environmental variables. The results indicated that the area of suitable climatic habitat of B. tomentellus before applying the exclosure (125868 ha) was considerably more than A. trichophorum (32515 ha). Nonetheless, applying the exclosure caused a 58% increase in suitable habitat of A. trichophorum versus 9% increase for B. tomentellus; which suggest that the grazing had a higher relative influence on A. trichophorum and removing the grazing pressure capacitated this species to retrieve its habitats. It should be emphasized that B. tomentellus should be considered as a more tolerant species to climatic conditions due to its prevalent distribution.

The floristic investigation of each area is one of the most effective methods for managing and conserving genetic storages of existing biodiversity. The Sheyda Protected Area with 23832 hectars is located in Chaharmahal Va Bakhtiari and its geographical position is 50 25ˊ to 50 44ˊ E and 32 33ˊ to 32 41ˊ N. The minimum and maximum elevation is 2100 and 3165 from sea level, respectively. In this study plant species in the area were collected and 316 plant species from 48 families and 206 genera were identified. The plant species mostly belong to Asteraceae (56 species), Fabaceae (36 species), Lamiaceae (32 species), Poaceae (29 species), Apiaceae (25 species) and Brassicaceae (18 species) families and Astragalus (17 species), Centaurea (10 species), Cousinia, Nepeta, Salvia, Stachys (5 species), Silene, Bromus and Hordeum (4 species) genera. Among these plants about 44.9 % are (medicinal), 34.8 % (pastural-feed), 6.6 % (poisonous), 5.3 % (weed), 4.4 % (industrial), and 3.7 % (soil conservation-cover) uses. The life form of plant species according to Raunkierʼs method are consists of 48.7 % hemicryptophytes, 31.3 % therophytes, 10 % camaephytes, 8 % geophytes and 2 % phanerophytes. The chorotypes of plants species showed that 64.2 percent (203 species) of the plant species belonged to Irano–Touranian zone. Other species in addition to Irano–Touranian zone grew in other geobotanical zones too.

Vegetation is the most important factor influencing the sustainability of rangeland ecosystems. Therefore, it is important to understand the environmental factors and their effect on vegetation and restoration of rangeland ecosystems. The aim of this study was to identify factors influencing on Gundelia tournefortii L. distribution. Accordingly, the information of Gundelia tournefortii L. was determined in six habitats in Isfahan province. Random- systematic sampling was conducted to calculate canopy and density of the species. In each rangeland place, climate, physiography and soil factors were identified. RDA ordination analysis using CANOCO software was used to investigate the vegetation relationship with environmental factors. In the cluster analysis and RDA ordination analysis, six main habitats of the species were classified into three groups. The first axis of ordination showed a very strong correlation with canopy cover and density and the second axis showed a very strong correlation with soil depth. According to study of the habitats of this species, annual precipitation about 250 to 500 mm, altitude 2300 to 2500 meter, slope about 10 to 40 percent and average of annual temperature about 10 ̊C to 12 ̊C are appropriate for presence of this species.

Iran's central Zagros is the homeland of some species of genus Stachys, one of the largest species of Labiatae family, such as Stachys lavandulifolia Vahl. species. Stachys lavandulifolia Vahl. is a plant 25cm long with fleecy and furred stem which ends to fleecy inflorescence and long fragrant fiber. Different medicinal effects have been attributed to this plant in the literature of Iran world's traditional medicine. The aim of this paper was to study the ecological factors of Stachys lavandulifolia not only to know ecological features of this plant, but also to take steps for keeping and using it. To this end, climatical, physiographical, physical and chemical features of the soil were investigated in the west of Esfahan, where it grows. The finding of the study indicated that this plant has suitable growth in regions whit average annual rainfall of 372.8 mm , average annual temperature of 10.2cm, annual evaporation 1955mm, average frost days 142 days, and semi- arid and cold climate. The results obtained from the physiography of range sites studied in this paper showed that this plant can grow both in places with different slops and fluctuations ( 6-23%) and in highest and lowest places with the high difference of 592.6m. the soil in which Stachys lavandulifolia grows has a silt clay loam, a little alkaline, without salt, and in terms of organic materials and the amount of Calcium and Potassium is average.

Climatic conditions largely determine the status and characteristics of plants and plant communities in different regions. Therefore, in order to study range plant species, the tolerance of each species to these factors should be determined. In this study, climatic features and requirements of two important grass species with conservation and forage importance (Agropyron trichophorum Richt. & Bromus tomentellus Boiss.) were studied in the Central Zagros. For this purpose, 19 bioclimatic variables used as inputs to Random Forest (as a machine learning approach) in R statistacial environment. The results showed that total annual precipitation (BIO12), the average temperature of the wettest season (BIO8) and the mean diurnal range (BIO2) for both species had the greatest importance and the sum of these three variables described more than 68 and 64 percent of variance in the B. tomentellus and A. trichophorum, respectively. The estimated accuracy by TSS index was calculated for B. tomentellus as 0.95 and Sensitivity and Specificity values were estimated as 0.93 and 0.96, respectively. For A. trichophorum, these values (TSS, Sensitivity& Specificity) calculated as 0.92, 0.89 and 0.93; respectively. The results of this study explain the cliamtic niche of the studied species. Top priority places, where protective actions has to be taken, can be determined using the results of this study. Potentially climatic suitable habitats can be proposed for reintroduction of these valuable species as well.

The effect of climatic changes including: temperature, CO2, and moisture content on photosynthetic characteristics and dry matter yield of rangeland species Bromus tomentellus Boiss – an important forage plant in the West of Isfahan province pastures – was explored in a factorial experiment with a completely randomized design. After collecting a mother plant of this species and asexual reproduction to required number, the climatic variables on each time step in the future (based on A2 climate change scenario) were applied as a treatment on pots except for one group which was taken as control. The photosynthetic pigments, including chlorophyll a and b, total chlorophyll, carotenoids, and aerial dry matter (as the criterion to determine the amount of plant yield in each pot) were measured in these groups. By recording these parameters and relating them to the climatic variables, the impact of climatic changes on them were explored. The results showed that the physiological response of species to the changes in the climatic parameters of temperature, CO2, and moisture content was different. A change in these three parameters (temperature, CO2, & moisture content) significantly decreased chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in the species under the study. Dry matter yield of single pot also decreased significantly (p

The effect of environmental factors on plant vegetation is different. Therefore, it is necessary to evaluate role of these factors in medicinal plants growth, development and essential oil. This study was performed to investigate the effect of factors on qualitative and quantitative variations of the essential oil of Verbascum songaricum in its habitats in central Zagros Mountains, Iran in 2012. V. songaricum aerial biomass was collected in flowering stages from four rangeland sites in Isfahan (Dareh Hose, Ghahiz, Ghaleghadam, Semirom) and one site in Kohgiluyeh, and Buyerahmad (Dena) provinces, Iran. The samples were dried in open air and their essential oils were extracted through digestion method. Gas Chromatography Mass Spectroscopy (GC-MS) was used to identify essential oil composition as Alcohol, Hydrocarbon, Amin, Acid, Ester and Ketone of species in five sites. The most important environmental factors such as climate, and physiographic, soil physical and chemical properties were determined. In order to investigate the relationship between environmental factors and plant essential oil, Ordination analysis was performed using Redundancy Analysis (RDA). The results of correlation analysis indicated that the most important environmental factors affecting the essential oil were annual rainfall (r=0.86), frozen days (r=0.86), Aridity index (r=0.86), Altitude (r=0.86), gravel (r=0.74), nitrogen (r=0.78), organic matter (r=0.62) and soil texture (r=0.68). Results showed that there was an increase in essential oil production in V. songaricum under semi-arid cold climate, uplands, higher precipitation, relatively light texture and fertile soil. According to RDA analysis, two habitats were identified. The first habitat was more appropriate for essential oil production of V. songaricum (Dareh Hose, Semirom and Dena) in comparison with the second one (Ghahiz and Ghaleghadam). As a result, the first habitat was considered as a suitable natural place for the cultivation and domestication of V. songaricum.

In this study, the ability of Generalized Additive Model (GAM) for mapping potential distribution of Ferula ovina Boiss, and the description of species response curves to environmental variables were examined in Fereidonshar region with area of 1000 square kilometers located in West of Isfahan province. The presence and absence data of the species were collected from 278 sites (including 138 presence sites and 140 absence sites) by random systematic method, and 9 soil variables, 22 climate variables and 3 physiographic variables were mapped with pixel size of 72*72 square meters by using interpolation techniques (krigging, Inverse Distance Weighting) for the entire studied area. Then, the relationships between presence and absence of the species with the environmental variables were examined by GAM method. According to the results, the presence of Ferula ovina was inversely correlated with some environmental variables including soil silt and clay contents and also its distribution was directly correlated with slope, distance from sea level, organic matter content, soil saturation percentage and average annual temperature. The model evaluation conducted by the separate data gave Kappa coefficient equal to 0.64 and ROC area under curve equal to 0.86. According to the produced potential habitat map and the response curves of the species, the presence of Ferula ovina is more likely in the habitats with mean annual temperature: 9-11 degree centigrade, slop: 25-50%, elevation: 1950-3000 meter (Above sea level), CaCO3 content of soil: 10-30%, organic matter: 4-6%, silt: 10-30% and soil saturation percentage: 45-60%. The GAM enables managers to identify appropriate areas for rangelands rehabilitation and protection programs. The produced model has a suitable performance in identifying regions with high growth potential and rangelands rehabilitation and protection programs.

A field experiment was conducted to investigate the effects of mono and mixed culture on crude protein contents of Medicago sativa L. and Bromus tomentellus Boiss, total nitrogen, available phosphorus and potassium of soil using factorial experiment based on completely randomized design with 5 replications. Treatments consisted of three crop compositions (M. sativa, B. tomentellus or mixture of the two), three density levels (low (4 rows, row spacing 70 cm), Medium (8 rows, row spacing 30 cm) and high (16 rows, row spacing 14 cm). Results demonstrated that the forage crude protein in mixed culture was significantly higher than in monoculture of B. tomentellus (p 0.05). Percentage of plant crude protein decreased with increasing plant density both in monoculture and mixed culture. Medicago sativa monoculture and mixed culture increased soil fertility that confirms the importance of forage legumes in forage quality maintenance and preservation of soil fertility. According to the results, mixed culture of M. sativa and B. tomentellus with 8 rows density (30 cm row spacing) is recommended in dryland fields of Fereydoon-Shahr and similar areas.

Identifying endemic medicinal plants needs is the main steps taken to mass production of them. The main purpose for the present study is to considering of habitat characteristics of Verbascum songaricum schrenk in central zagros region in Iran. The current study was conducted in five rangeland sites in Dareh Hose, Ghahiz, Semirom, Ghale Ghadam and Dena as the most important V. songaricum habitats in Isfahan and kohgiluyeh and Buyerahmad provinces. Ecological factors including climate, physiography and soil physicochemical properties were evaluated. To determining similarity and differences between habitat, cluster analysis was used. The results showes V. songaricum grows where areas with precipitation between 300-500mm ranges, average annual temperature of 9.4 C and semi cold climate. Electrical conductivity of soil had a range between 0.5 to 0.9 ds/m and its organic matter varied from 0.3 to 0.9 %. According to results, the species is distributed in southern and eastern aspects and 2400 to 2900 meters above sea level. with respect to cluster analysis, study areas were located in two main habitats where the first one involve Dareh Hose, Ghahiz and second ones include Semirom, Ghale Ghadam and Dena.

Dorema   ammoniacum D. Don. (ammoniac plant) belongs to   Apiaceae family and Dorema genus. It is one of the most important   endemic medicinal plants in its family which grows in the arid and semi-arid   areas in the regions of Iran and some of the Asian countries such as   Turkmenistan, Afghanistan, Pakistan and India. This study was carried out   with aim of the extraction and identification of constituents of D. ammoniacum   D. Don. in   the western areas of Isfahan province, Iran. For this purpose, after the plant   collecting in the mentioned area its target organs namely stem and leaf were   separated, air dried, milled and weighted in the certain amount. Then the   essential oil of the plant was isolated by hydrodistillationmethod   and analyzed by GC/MS device. The results indicated that major components were Limonene   (49.18%), Neophytadiene   (10.21%), beta Caryophyllene   (3.54%), Phytol (2.61%) and Neryl acetone (1.46%).  Several therapeutic cases have been reported in traditional medicine and currently in contemporary medicine for Dorema ammoniacum D. Don. that some of them are include the treatment of cough, vasodilator, anti-flatulence and anti-microbial. Also, the mentioned plant has varied applications in the fields of foods, cosmetic and detergent industries.

The effects of plant density and water stress on yield of Medicago sativa and Bromus tomentellus was studied. A greenhouse experiment was conducted at Isfahan University of Technology in 2013. The experiment included 18 treatments, three crop compositions (M.sativa, B. tomentellus or mixture of the two), two plant density levels, three watering regimes and four replicates, arranged in a completely randomized block design. Results showed that total yield of M. sativa mono-cropping was higher than mixed cropping and it was higher than B. tomentellus mono-cropping. Land Equivalent Ratio (LER) values were less than 1 for all mixed cropping treatments, indicated the interspecific competition in mixed cropping. The biomass production per plant decreased with increasing density, competition for resource utilization and water stress. Compare of above-ground and below-ground dry matter showed that M. sativa appeared to be more constrained by intraspecific than by interspecific competition, Conversely, B. tomentellus was more suppressed by interspecific competition exerted by M. sativa than by intraspecific competition. Relative competition intensity (RCI) values were positive for B. tomentellus and negative for M.sativa, implying that competitive ability of M.sativa was higher than B. tomentellus in mixed cropping .

In order to analyze density measurement methods, a study site with four replicates in Fereydoonshahr characterized with vegetation type Astragalus verus-Bromus tomentellus was selected. In each site (an area with 5000 m2 in dimension 50*100m), real density was calculated by counting all individuals of Astragalus verus. Samples were taken in random-systematic manner. Within each replication, five transects 100 m in length were established and given sample size for each method, some points were selected in randomized manner and density measurement methods(Closest Individual Method, Nearest Neighbor Method, Random Pairs Method, Point Centered Quarter Method, Wandering Quarter Method, Angle Order Method, Corrected Point Distance Method) were implemented. Difference between density measurement methods by control method counting was evaluated using LSD method. According to the results, the closest estimation to control is nearest neighbor one. Point Centered Quarter Method, Wandering Quarter Method, Angle Order Method, and Corrected Point Distance Method showed significant difference to control. The largest and lowest sample size was attributed to Angle Order (33) and Wandering Quarter Methods(125) among others. The regular and T square had longest and shortest measurement times. The nearest neighbor showed the highest accuracy and Wandering Quarter as well as Point Centered Quarter had the least accuracy.

Gundelia tournefortii L. (Tumbleweed) has been identified as one of the well-known and widely distributed plants with various applications in some of Asian and North African countries. It belongs to the (Asteraceae) family and grows in the Middle East particularly in the temperate, mountainous and semi desert areas of countries such as Iran, Iraq, Turkey, Jordan, Syria, Egypt, Turkmenistan and some regions of Azerbaijan and Armenia. The aim of this study was to identify of the chemical components of G.Tournefortii L. in some of its habitats into Central Zagros area, Iran. In this regard, G. tournefortii L. was collected from some of its natural habitats in the mentioned area and air dried. The essential oil of the plant was isolated by hydro-distillation with a yield of 0.8 % (v/w). Also, the chemical compositions of volatile oil were analyzed using GC-MS. The results indicated that major components were palmitic acid (12.48 %), lauric acid (10.59 %), alpha ionene (6.68 %), myristic acid (4.45 %), 1-hexadecanol, 2-methyl (3.61 %), phytol (3.6 %), and beta turmerone (3.4 %).  Gundelia tournefortii L. is known as a plants with many therapeutic properties especially in traditional and contemporary medicine in the world. Also, this plant has a useful nutritional solute such as potassium and calcium.

Determining habitat suitability is one of the most important elements of management and conservation of plant and wildlife species. A suitable habitat will have a significant impact on the survival and reproduction of species. Nowadays, the development of statistics and geographic information system has enables us to determine possible habitats for plant species via using geographical distribution modeling techniques. Using the Ecological Factor Analysis Model (ENFA), the present study has modeled the habitat of Fritillaria imperialis L., as a species with numerous industrial and pharmaceutical applications. To this end, species’ presence data was gathered with systematic sampling method with 500 presence points. Then the data was registered and then, the data was ultimately converted to a map of the vector format. Environment variable maps such as topographic, climate, and soil were generated by using geostatistical and GIS methods. Finally, the habitat map for this valuable species was generated. According to ENFA analysis, the variables of the amount of absorbable potassium, the amount of absorbable phosphorus, Digital Elevation Model, the amount of annual precipitation, and the slope direction of region, are the most significant factors, influencing the habitat selection for Fritillaria imperialis L in the study area. The amounts associated with being margininety, specialization, and tolerance in this study were 1.547, 6.325, and 0.158, respectively indicate that Fritillaria imperialis L is specialization species within its habitat sites. Boyes index was used to verify the correctness of this model, which was calculated to be 0.092. The results of the present study suggest that using alternative habitats can prevent the irreversible negative consequences like reduction or extinction of this valuable species.

Vegetation cover is one of the most important factors for ecosystem sustainability; thus, recognizing and understanding factors affecting the establishment and distribution of vegetation communities are necessary. This study was aimed to determine the relationship between vegetation and soil parameters of Ardestan rangelands, Isfahan Province. Primarily, the vegetation types were distinguished in the field using physiognomic method. Plot size was determined applying minimal area method. The number of plots was determined using statistical method. Systematic randomized sampling was used and performed along three transects of 100 m length. Ten plots of 6m2 were established along each transect at 10-meter intervals. Three soil profiles were dug in each area and soil samples were taken at a depth of 0-150 cm to study 21 soil factors. The results of factor analysis showed that among variables studied, 17 variables were the most effective factors on vegetation types of the study area. To determine the effect of environmental factors on the establishment of vegetation, canonical correspondence analysis was used applying CANOCO software. Ordination results showed that environmental factors such as soil texture, lime, potassium and electrical conductivity had the most important role in the establishment and expansion of plant communities in the study area.

Species distribution maps have been widely developed based on ecological niche theory together with statistical and geographical information system in plant ecology. The current study aimed to evaluate Artificial Neural Network (ANN) in mapping potential habitat of Ferula ovina Boiss in Ferydunshar rangelands، Isfahan. This is known as valuable forage and medicinal species. Environmental data (independent variables) and species occurrence data (dependent variable) were required to determine potential habitat of a given species. Some physical and chemical soil properties، climate and physiographic variables were mapped for the entire studied area using krigging and inverse distance weighting methods. F. ovina occurrence data were collected from 278 sites including 137 presence and 141 absence sites. The relationships between the studied environmental variables and F. ovina occurrence data were explored using ANN method. According to the sensitivity analysis، occurrence of F. ovina mostly correlated with silt and sand percentage، elevation slope، and organic matter. Model evaluation based on Kappa coefficient (0. 66) and Receiver operating characteristic (ROC=0. 9) showed good model fitness in relation to reality on local scales. The ANN technique enables managers to identify appropriate areas for rehabilitation practices such as direct seeding and planting.