جستجوی مقالات مرتبط با کلیدواژه « Astragalus gossypinus » در نشریات گروه « کشاورزی »

Iran has natural areas with different and unique medicinal plants that are valuable economically.In spite of existing many capabilities of medicinal species such as Astragalus gossypinus, due to the lack of management and proper exploitation of the gumtragacanth, has caused the destruction of this species; So, it has resulted economic problems. This research investigated the yield and economic value of gumtragacanth from Astragalus gossypinus on sustainable livelihood in summer rangelands of Golestan province.Sampling was done random-systematicly and three 300-meter transects, 10 plots along each transect was placed.For estimating the density of available species; 10 plots of 4-mwere placed in each plant type and the number of availabe species and the availabe percentage of Astragalus gossypinuswas determined in each type. The average production of gumtragacanth is 50 gr.The economic value determined by market pricing method. After estimating the total density of Astragalus gossypinus.The results showed that the highest available species density was in type of Ju. polycarpus-On. cornuta-St. barbata with 6,882,750 and the lowest available species density was in type of Ar. aucheri-St. Barbatawith 665528. The total amount of available gum tragacanth was 729944.9 that with 10% depreciation was 4.72994 kg. The total economic value of gum tragacanth was 547458000000 rials. According to the economic value of gum tragacanth, the management of Astragalus gossypinus should be in a multiple use way to increase economic income.

Astragalus gossypinus is one of the most important plants covers the mountainous rangelands of Taleghan, Iran. This study provides habitat suitability map for Astragalus gossypinus using ecological niche factor analysis (ENFA) at the middle Taleghan rangelands. For the study, species presence map (120 points) plus a map of environmental variables were prepared. The last map included layers such as gravel, pH, lime, organic matter, N, K, P, sand, clay, silt, slope, aspect and height. Geostatistical methods were used to depict the soil variables maps. The accuracy of the model was 92.3% using the Boyce index. Therefore, the accuracy of the model results is high. Kappa coefficient obtained 0.69 by matching the prediction map with ground truth. This indicated that the ability of ENFA model was good in preparation of the A. gossypinus habitat suitability map. The results of this study showed that A. gossypinus tends to be more distributed with increasing height, depth and organic matter. The species also has a positive response to variables such as lime, slope and north aspect. Value of the marginality, specialization and tolerance obtained 1.708, 2.763 and 0.362 respectively. It can be concluded that the A. gossypinus widespread species which has a good tolerance to environmental variables in the study area. The results of this study can provide arrangements for conservation and restoration of habitats with current or potential distribution of A. gossypinus and help to properly rangeland management.

In the present study, forage quality of three range species including Astragalus gossypinus, Trifolium repens and Poa bulbosa at three phenological stages, (vegetative growth, flowering, seed maturity time) in Borujerd county of Loretan province were evaluated. Data were collected by random sampling using 10 individual plants on transect line in 5 replication. Qualitative indexes were measured and data were compared using ANOVA and Duncan test. Results indicated that DMD is not significant between different species, but it was significant differences (p< 0.01) among the various phenological stages. The highest and the lowest were 34.61 and 24.24% respectively for seeding and before flowering stages. The amount of crude protein was significant at (p< 0.05) in different species, phenological stages and their interactive effect. The highest and the lowest crude protein were obtained in 21.06 and 17.97% in Trifolium repens and Poa bulbosa respectively. The amount of crude fiber was not significant difference between species, on the other hand, in different phenological stages and their interaction was significant at (p< 0.05).The highest and the lowest of crude fiber were 94.30 and 20.86% in seeding time and before flowering phenological stages. The highest and the lowest of amount of ADF were obtained in Poa bulbosa and Trifolium repens with 57.6 and 31.26% respectively. According to obtained results, Trifolium repens, Poa bulbosa and Astragalus gossypinus had better forage quality respectively in before flowering stage where this issue indicates the best time for animal grazing is in May and June.

This study aimed to determine the most important ecological factors affecting the canopy cover of Astragalus gossypinus in some parts of semi-steppe rangelands of the Kurdistan province. Field survey was carried out in three areas of Kurdistan meadows including Dezli, Narran, and Murvarid saddle. The number of plots, according to the characteristics of the vegetation and other environmental factors, was calculated to be 6 for Dezli, 3 for Naran, and 4 for Murvarid saddle. The plots of vegetation were sampled in a random-systematic manner in an area of 1 × 1 m and along two transects of 100 m. Soil sampling in each plot was performed with three replications and at the depth of 0 to 50 cm at and between the base of the plants. Factors such as soil, clay, silt, sand, gypsum, lime, electrical conductivity, pH, phosphorus, calcium, magnesium, stones and pebbles, nitrogen, carbon, and potassium were measured. For the analysis of soil and vegetation, ANOVA, and in order to determine the effect of different environmental factors on the vegetation cover, multiple regressions were applied. To determine the most important factors affecting the canopy cover of vegetation, principal component analysis was also used. The results showed that the factors including carbon, potassium, pH, magnesium, phosphorus, calcium, lime, nitrogen, clay, sand, average annual rainfall, and the canopy cover percentage were significantly different at the level of 1%; while, the factors such as gypsum and electrical conductivity were not significant among the different habitats. The regression results showed that the factors including lime, height, and precipitation justified the changes of cover 25%, 12% and 7%, respectively.

Interspecific interaction of tree species is an important process in establishing spatial structure of species associations in ecosystems with low species diversity. This study was aimed to investigate the interspecific interactions of Montpellier maple (Acer monspessulanum L.) and two accompanying species (i.e., Amygdalus scoparia and Astragalus gossypinus) in a site close to Firooz Abad, Fars province. A 200 m × 200 m sample plot was selected in a part of the site. The spatial locations of 629 individuals were measured together with their tree species, height and crown area. In addition to bivariate g(r), M(r) and P(r) were applied to explore more details about interspecific species interactions. The results showed that A. monspessulanum had the highest density, mean height and crown area compared to other species. The results indicated negative interspecific interactions of tree species, which was decreased with increasing distance. Negative interactions were observed between A. monspessulanum with A. scoparia and A. monspessulanum with A. gossypinus up to spatial scale of 3 m and 10 m, respectively. Moreover, A. monspessulanum and two other species showed repulsion up to 7 m distance. In general, it was concluded that A. monspessulanum showed negative interspecific interactions with A. scoparia and A. gossypinus in the study area. This might be caused by environmental heterogeneity and resource limitation. Furthermore, M(r) and P(r) explored more details about type and spatial scale of negative interspecific interactions of A. monspessulanum with two other species.

Habitat suitability prediction of important plant species in formal and indigenous Knowledge is known as one of the considerable factors in rangelands reform and development, since one of the main points of success or failure of these activities is adaptation with needs and culture of the area residents. This survey is about feasibility study of preparing prediction map of the possibility of presence of some range species being important for natives, local experts and having Multifunctional value. This study was conducted in Dilegan rangeland in Kohgiluye and Boirahmad province. Important species were identified based on interviews with local experts, scientific centers associated with natural resources and tribal affairs. Then logistic regression model was used for habitat prediction map of the selected species and regarding the purpose of study, vegetation data and environmental factors were collected in the rangeland. By creating relationships between environmental variables and the presence or absence of species and applying these relationships in GIS, habitat prediction map of Astragalus gossypinus Fischer, Prangos ferulacea (Schlecht) Boiss. and Ferulago angulata (L.) lindi was created in the ArcGis version 3.9. Kappa (κ) was used to evaluate the prediction habitat maps. Results showed that gradiant analaysis of environmental variables by logistic regression can be used as one of the appropriate methods for preparing habitat suitability prediction map of plants. In this method, by determining the presence or absence of plant species, its relationship with environmental factors is identified, and in other areas, in case of knowing environmental factors, predict the possibility of presence of plant species.

Produced ash and coal from fire influence the soil and few studies about these effects are available. Then this study performed to investigate the effect ash and coal on hydrological, physical and chemical soil properties in Charat rangeland that had a history fire formerly. Systematic-random sampling was implemented in two plant types Astragalus gossypinus and Artemisia aucheri using 6 transect and 4m2 quadrates 60 and plant and soil samples were obtained. Experimental treatments were prepared including control soil, composition soil and ash manually and also with artificial rain, composition soil and coal manually and also with artificial rain in the laboratory and were measured characteristics of the texture, saturation moisture, pH, organic matter, field capacity, wilting point, available water and retention capacity. ANOVA results for mean comparison soil, ash and coal properties had shown that ash had the percent of silt and pH more than soil and organic matter and bulk density lower than soil. Also the results of multivariate analysis for indication of effects treatments had shown that manual composition of ash and coal into soil had increased field capacity and available water while composition soil and coal with artificial rain had no significant effect on them.

This study has been done with the purpose of modeling and prediction of the habitat Astragalus gossypinus map using Logistic regression (LR) and Ecological niche factor analysis (ENFA) in summer rangelands of Baladeh, Nour in Mazandaran province. To achieve this objective, environmental map variables were prepared with the help of ArcGIS®9.3 techniques in cell size of 10 × 10. Also, 80 site as well as the presence or absence of species was recorded by sampling classified-random. For each sampling site was recorded information about the presence or absence of species and environmental variables, and the relationship between species distribution and environmental factors was determined by using logistic regression and ecological niche factor analysis, and forecast maps the distribution of the Astragalus gossypinus was produced in the study area. According to LR results, Elevation, pH, organic carbon, average temperature of the wet season and average temperature during the dry season were the most important environmental factors influencing the distribution of the species. According to this model, variable aspect, sand Percent, TNV of soil, precipitation in the wet season and average temperature during the coldest season were used as influential environmental variables. Evaluate the correctness statistical models were performed by using the kappa coefficient and ROC area under the curve plots. Value indices, respectively 0.42 and 0.78 for the logistic regression model and 0.84 and 0.92 for the ecological niche factor analysis, which represents that profile model shows higher accuracy than the discrimination group models in the study area.

The relationship between plant species and climatic factors has always been an important subject in plant ecology and the use of multivariate statistical methods might be effective in detecting the relationship between climatic factors and the distribution of plant species. In the present study, climatic characteristics of Astragalus gossypinus Fisher producing tragacanth stretched in a relatively vast area in Isfahan province (approximatley seven percent of natural habitat of Isfahan province) to shed lights on determinant climatic factors on distribution of this species were investigated. In this study, 56 climatic variables were evaluated in the months of January, March, and July in the annual interval and to reduce the number of variables and determine the most important factors. Factor analysis was applied using principal components analysis. The results showed that four factors, namely cooling temperature-humidity, precipitation-storm, cloudiness, and windiness account for 39.05%, 32.77%, 11.44%, and 8.63%, and totally 91.88% of the variance of the data, respectively. Also, the cooling temperature-humidity factor has the greatest impact on presence of this species, therefor, in areas where this species can be seen, the cooling temperature-humidity factor is positive and vice versa.

The purpose of this study was to assess the logistic regression model capability to map the spatial distribution of plant species in Taleghan Miany rangelands. Systematic-random sampling method was used to collect vegetation and environmental data (such as topography and soil factors). Three transects with 150 m lengths were established in each sampling unit and the vegetation cover percentage were determined in 15 plots along each transect. Soil samples were collected from the two sampling plots in each transect randomly. Geo-statistical methods were used to produce the environmental maps. Topographic maps were also produced using digital elevation model. Species distribution models were prepared using logistic regressions equations in Geographic Information System (GIS). Kappa index (k) was used to evaluate the agreement between prediction models and field data. According to the results, kappa index obtained for Agropyron intermedium habitat model was 0.83. The calculated Kappa for Stipa barbata and Astragalus gossypinus habitat models were 0.79 and 0.80 respectively. This index for Thymus kotschyanus habitat was 0.68. This study indicated that logistic regression model could predict the habitat suitability of the four studied species appropriately. The produced logistic regression model for predicting Agropyron intermedium habitat was more efficient because this species has more specific habitat requirements. The results of this study can be used in rehabilitation, conservation and management programs in rangeland ecosystems.

Astragalus gossypinus Fischer is one of the most important range plants in west region of Isfahan، which is very critical for soil conservation and people''s economic life. Nevertheless، the grazing pressure and overuses cause habitat destruction. This study has been done for determination of its potential habitat in Lenjan and Flavarjan parishes of Isfahan province. To achieve this purpose، spatial data of this specie''s presence used as suitable places for its growth and the environmental condition (Climate، Soil & Physiographic) used for recognition of its habitat''s necessities. Soil data turned to soil maps using antecedent studies and interpolating soil profile points. Climatic and physiographical data have been prepared as well and got ready to be imported to the ultimate model. By importing the information layers in ENFA model and using harmonic mean analysis in Biomapper software; the map of Astragalus gossypinus potential habitat has been created. The results show that gravel percentage، soil potassium، saturated moisture، electrical conductivity and annual precipitation are the most important factors in habitat choosing by Astragalus gossypinus in study area. 25300 hectares of the study site are potential habitat of Astragalus gossypinus which is 16 percent of the study site. To evaluate the verity of this model، Boyce''s index has been used and model rectitude in this test was determined 85. 2 percent.

Due to the effect of atmospheric carbon absorption and sequestration، this study is investigated the effects of exclosure and grazing on carbon stoage by Astragalus gossypinus in the part of the cold semi-arid rangelands of Vezvar in Behshahr. After determination of key area، two sites consist of exclosure and grazed area was selected and plant and soil sampling was done by random-systematic method. Thus، 20 plants and 40 soil samples were collected totally. Conversion coefficient of enclosure rangeland (٪0. 78) was more than the grazed rangeland. Carbon stoage rates of roots with 19/9 kg/ha in exclosure area and grazed area with 8/33 kg/ha was more than the stem and leaf. Overall، the rate of carbon stoage in enclosure area with 1036467. 022 kg/ha was more than grazed area with 976082. 806 kg/ha and had not significant different. Investigation of carbon storage in soil showed that soil was stored more carbon to the plant biomass.

Given the potential for carbon storage in plant tissues، this approach has a serious interest in recent decades. Therefore، the ability of carbon storage in Astragalus gossypinus and Astragalus parrowianus were examined in part of alpine pastures in Kermanshah Province. After determining the representative districts، according to 4 main aspect and 5 category elevation was determined representative area. Also in each representative area 3 transect parallel to of up slope to down was placed (total 60 transect) and interval 10 m was placed plots (total 300 plot) and aerial and underground biomass carbon values ​​of those species were measured. Regarding to the results of mean compression SNK the least of carbon storage in category elevation (1900-2100) that was determined in north aspect. Also according to the results، Astragalus parrowianus Species has more carbon storage capacity than Astragalus gossypinus species. This ability is due to more vegetation percentage and more aerial and underground biomass of Astragalus parrowianus Species in compare with Astragalus gossypinus Species. These abilities cause to more organic carbon storage of Astragalus parrowianus Species.