setareh bagheri

This study aims to assess the variations in the trend of drought using indices in Northwest Iran as vegetative cover plays a vital role in environmental stability.

To achieve this goal, the study includes three stages: determining the Standardized Precipitation Evapotranspiration Index (SPEI) using monthly temperature and precipitation data from meteorological stations, calculating the Vegetation Health Index (VHI) based on derived datasets from MODIS satellite images for the period 2001-2021, and examining the correlation between indices to determine the duration of vegetation cover response to water scarcity and identify trends at 3, 6, 9, and 12-month time scales.

Based on the results of the Mann-Kendall test, the stable (48.56%) and increasing (50.43%) trends cover most of the studied areas and a smaller area had a decreasing trend (1.01%) trend. Additionally, positive correlations between VHI and SPEI were observed across all time scales. The SPEI-3 months showed the highest Pearson correlation (R2= 0.83) with VHI values for the growing season, indicating that water accumulation in the past 3 months had the greatest impact on vegetation cover.

This study, while emphasizing the necessity of monitoring and managing drought, with a focus on vegetation cover status in Northwest Iran, especially in East Azerbaijan province, introduces drought indices as a crucial component of the drought monitoring system.

Palatability is one of the important characteristics of rangeland plants that is related to their acceptance by animals for grazing (Arzani, 2009). It is also defined as an animal's pleasurable reaction to its food depending on the taste, smell, texture, and appetite of nutrition animal (Church, 1988). Molyneux and Ralphs (1992) reported that while palatability means acceptance, it is not necessarily desirable. In other words, a nutritious food may not have a specific smell or taste in terms of preference, and it may not be attractive or taste bad. In terms of nutritional needs, most of the animal food may be composed of plants that have a moderate degree of palatability.

This research has been done in the rangeland of Deh Sheikh Village of Kohgiluyeh and Boyer-Ahmad provinces. To conduct this study, first two healthy three-year-old goats (females) of Mamasani breed were randomly selected from a herd that belonged to the same area. Then, three important rangeland species including two perennial species including Gundelia tournefortii and Bromus tomentellus and one annual species, Aegilops triuncialis were selected by video method to determine the palatability of species at different stages of growth including vegetative growth, flowering and seeding. For this purpose, the grazing time of goats from any plant was monitored at intervals of 30 minutes in three times including morning, noon and evening and in two repetitions (two days in each growing season) with a suitable distance from the goats. Finally, the palatability percentage of each species was calculated separately.

The results of perennial species in vegetative growth and flowering stages showed that there is no significant difference in palatability between different times of the day (morning, noon and evening). In other words, the consumption of goats from any specie is the same at different times of the day in the stages of vegetative growth and flowering. It was also observed that G. tournefortii has more palatability than B. tomentellus in vegetative growth and flowering stages (Figures 2 and 3). Also, the palatability results of perennial species in the seeding stage indicate that there is no significant difference between different species in terms of palatability at any time of the day. In the case of A. triuncialis, it was found that the palatability of this species at different stages of growth has a significant difference at the level of 1%, but at different times of the day there was no significant difference in palatability (Table 3). Also, according to Figure 7, it was found that the highest and lowest palatability of this species are related to the stages of vegetative growth (27.21%) and seeding (8.09%), respectively.

In the vegetative and flowering stages of G. tournefortii, which is a forb species, it has more palatability than B. tomentellus (grass) for goats. In fact, if G. thournefortii thorns are not for livestock, this species will appear in the form of a palatable species and will be selected by goats. In this regard, Shoaib Amjad et al. (2014) stated that the morphological characteristics of plants such as thorns, hairs, bitter taste and unpleasant reduce palatability. The findings of Arzani and Naseri (2007) in relation to the study of goat grazing behavior of G.tournefortii also showed that G.tournefortii is more grazed by goats at the flowering stage when the thorns are soft. The results of some studies also showed that even in the flowering stage, changes in flowering time and flowering and fruiting rates affect the behavior of animal species that are directly or indirectly dependent on plant phenology. On the other hand, the results of the seeding stage of perennial species showed that in the sowing stage of B.tomentellus species has a higher percentage of palatability than G.tournefortii species in all three times of the day (Figure 5). The results of this study on A. triuncialis palatability (annual species) showed that the highest and lowest palatability of this species for goats coincides with the stages of vegetative growth and seeding (Table 3 and Figure 6). It should be noted that the decrease in palatability of most plants with the development of vegetative stages is almost confirmed for most species. So that in the early growth of forage is very green and palatable and with the development of puberty most of its nutrients are reduced (Tan et al., 2003; Rebole et al., 2004; Alikhahasl, 2008). The results of some studies also confirm that forage quality indicators also change as the growth stages progress. In fact, forage quality changes constantly as plants mature, and these changes are so rapid that a significant reduction in forage quality can be detected every two or three days (Twidwell and Wegenhoft, 1999). The results of Heady and Denis (1994) show that in the vegetative growth stage of forage plants, the amounts of crude protein, sugars and vitamins are high; but fiber and lignin levels are low. According to the results of this study, it can be said that future studies can extend these results to vegetation, including a wider range of vegetative forms, because our results emphasize the importance of maintaining the complex structure of plant communities in rangelands (different species, vegetative forms and growth stages). To maintain their nutritional value over time. Although goats are known as browser and are interested to shrubs, but as Arzani and Naseri (2009) reported, in the absence of shrubs, this animal will graze on grass and forb in the rangeland, so most herds Countries A combination of sheep and goats can be seen.

Rangelands played an effective role in the country's economic and political development prior to its dependence on oil and its derivatives. Therefore, paying attention to the environmental and social stresses brought to these ecosystems highlights the need to use new technologies to diversify production sources and reduce costs. This study was conducted at the Taleghan range station with the aim of financially evaluating electric fences to encourage pastoralists to use this technology in rangelands. For this purpose, the income from the fencing project was investigated. The financial evaluation of the electric fencing project and the time period for its capital return in 2016 was done using the equations of net present value, benefit-cost ratio, internal rate of return, and net present value criterion at different discount rates. The total fixed and current costs of this project were equal to 330 million rials. The income from animal meat production, medicinal plants, the added value of electricity production, the income from the replacement of shepherds, and the net income were equal to 73%, 23%, 7.5%, 103%, and 120% respectively. The criterion of net present value at different discount rates was equal to 127%. Considering the economic nature of fencing technology and the existence of economic benefits resulting from it in the form of a wide spectrum of ecosystem services for the beneficiaries of rangelands, the importance of promoting the use of new technologies in rangelands to maintain and support the production chain of rangelands is highlighted.

The main goals of the study were to decipher the English language needs of dental students and to evaluate the effectiveness of the recent official English for specific purposes (ESP) book published for Iranian dental students by SAMT Publication. Accordingly, the study sought to determine whether this book has the potential to meet the specific needs of dental students. Needs analysis data were gathered by interviewing 34 ESP stakeholders from two universities of medical sciences in Iran. The interviews attempted to examine the students' language needs, lacks, and preferences. Following the needs analysis, six evaluators evaluated the coursebook based on a book evaluation form. The results obtained from the needs analysis highlighted the significance of practicing 4 language skills in addition to medical terminology.      In terms of students' language skill lacks, it was found that the majority of the students had problems in listening, speaking, vocabulary, and pronunciation. The participants also reported the learners' preferences and some drawbacks of current ESP courses with respect to learning styles and methodology. Following the book evaluation process, it was concluded that even though the book did not gain a fully satisfactory score, among a few ESP books published for Iranian dental students, this book was the most appropriate one to be used in ESP courses. However, considering some points can surely improve our future ESP books and give the material developers a better understanding of ESP materials.

Rangeland management is more difficult than other areas because the management of these areas includes integration and management of forage production, livestock production and forage utilization at one time and one place. Therefore, it is important to consider the various dimensions of the stakeholder groups in the management and long term planning of rangelands. This research was conducted with the aim of investigate the attitude of stakeholders towards rangeland apportion in three provinces of Lorestan, Markazi and Semnan. This included apportioning between and within utilization units and determining the boundaries of rangeland using common parlance, law, or both.

In order to collect data, levels were first considered for each of the variables. Then the data were collected using a a standardized questionnaire and analyzed using the chi-square test in SPSS software.

From the results of the frequency of the variables, it was found that from the point of view of the most of the respondents, the apportion between the utilization units has been done; While the apportion within the utilization units has not been done. In addition, in Lorestan and Central provinces, 68.90% and 68.35% of stakeholders, respectively, gave more importance to the legal in determining the boundaries of rangelands. But in Semnan province, 40.67% of the stakeholders have given more importance to custom. Also, the result showed that most stakeholders were satisfied with the apportion of utilization units between and within units. In Lorestan province there was a significant relationship between the job variable (P <0.01) and invasion to rangelands (P <0.05) with satisfaction with the apportion between utilization units, invasion to rangelands (P <0.05) with satisfaction with apportion of utilization units and education (P <0.05) and tendency to leave the job in custom or legal way in determining rangeland boundaries. Also in Markazi province, there was a statistically significant relationship between the variable of nomadic cooperative company (P <0.05) with the apportion between utilization units and in Semnan province between the variable of rangeland condition and the variable of apportion within utilization units (P <0.05).

According to the findings of this research, from the point of view of the stakeholders, the apportion utilization units is a problem in Iran, but in other countries, the apportion utilization units has not been a problem.Therefore, it is necessary to solve this problem based on local knowledge of the region. Because this leads to making unbiased decisions based on scientific and objective information. In addition, rangeland protection policies and measures can be improved based on the attitude of the stakeholders. In general, investigating the attitude of the stakeholders, in addition to providing important insights about the observations, understanding and interpretation of the social effects and ecological results of the destruction of rangelands, guarantees the support of the stakeholders in the long term.

Plain ecosystem is highly vulnerable to environmental changes, and drought is the most famous ecosystem change driver that is difficult to identify after its occurrence. In this research, to study the slope of vegetation changes against drought, the NDVI index of MODIS images and the SPI index from 2001 to 2016 were used and the map of vegetation changes against drought with five drought stress classes included very low classes, Low, moderate, high and very high, so that a suitable assessment of the drought can be made at specified time scales. The results of slope pattern of spatial change of vegetation against drought showed that across the plain vegetation changes have declined, and from east to west of Qazvin plain, the slope of vegetation changes and land susceptibility to drought have been reduced. So that the most percentage of area in a one-month drought related to the drought class is very low, but in droughts of 3, 6, 9, 12, 24 and 48 months, the highest percent of the area belonged to moderate and high drought classes. The results of this study, the determination of the level of vegetation changes in against drought in the past years and prediction of these changes in the future years, can be used in the planning and optimal use of resources, control changes in the future.

Using satellite imagery is a reasonable option to overcome the field visits problems and limitations to evaluate the vegetation cover over the years. The present research has conducted to specify the percentage of vegetation cover of rangelands using Geographic Information System (GIS) and vegetation indices. The study area is located in Qazvin plain rangelands, Iran. In this study, the MODIS satellite images was used to extract the vegetation canopy percentage map in June 2017. To make a correlation between vegetation canopy percentage and satellite data, 160 plots (10*10 m2) were marked on the study area with an area of five thousand square kilometers so that each 10 plots was located on the perimeter of a hypothetical circle with a radius of 150 meters having 100 meters interval. Vegetation indices were extracted from the satellite images. The correlation between vegetation indices and field data were calculated by analyzing simple linear regression. Then, a vegetation cover model obtained for each of the vegetation canopy percentage. The study results showed that the correlation coefficient of the NDVI and EVI indices were 0.63% and 58% respectively and the NDVI index was selected to prepare vegetation cover map because it had the highest correlation coefficient. Using the NDVI index model, the vegetation canopy for five percentage classes namely 10%>, 10 -20%, 20 -30%, 30 -50% and more than 50% were prepared. The study results showed that 10 to 20% vegetation canopy class is prevailed. The study results also showed that MODIS and NDVI indices are suitable tools to create vegetation canopy map in the rangelands dominated by shrubs and grasses.

Range management plans (RMPs) are one of the main tools for the management and utilization of rangelands in Iran. Range size, number of animal units, and rangeland users are considered as the most important factors influencing RMPs. This study was conducted in the rangelands of Isfahan province in 2008 in order to study the relationship between range size, the ratio of permitted animal unit to existing animal unit and number of rangeland users with range condition. Accordingly, the list of RMPs was prepared. Then, the range size, the number of permitted and existing animal units and rangeland users were determined. After that, the range condition was determined using four-factor (winter rangelands) and six-factor methods (summer rangelands). Finally, the relationship between range size, the ratio of the permitted animal unit to the existing animal unit and number of rangeland users (separately and commonly) with range condition was verified by using spearman correlation and discriminate analysis. Results indicated that there was a significant relationship between range size (P≤ 0.01) and the ratio of the permitted to the existing animal unit (P≤0.05) with range condition in summer rangelands. Therefore, it is concluded that range size and animal unit could be considered as one of the factors affecting rangeland degradation.

The forage and Astragalus productions are main products and major sub-products of semi-arid regions of Isfahan rangelands. Some economic indices of harvesting and selling of Astragalus sub-products were evaluated. Therefore, the statistical papulation in the study included beneficiaries operators of the forage and Astragalus product. In addition, data were obtained through field work using unstructured interviews as well as direct observation. Results showed that marketing margin for Astragalus gossypinus and Astragalus verus were 44.44 and 42.5 percent, respectively. Besides, annual net income obtained by harvesting of forage species was 106 million Rials. That was nearly 76% of annual income of each rural household. And also, the annual net income obtained by harvesting both species of Astragalus gossypinus and Astragalus verus were 11.78 million Rials, that was 8.47% of each household income. Royalties for forage and Astragalus product were also estimated 2.65 billion Rials per hectares annually and 5.46 billion Rials per year, respectively. Furthermore, the findings indicated that the share of annual employment for forage production and Astragalus utilization were estimated 120 and 68 people, respectively. The share of Astragalus by-product of total employment obtained from forage and by product was also estimated at about 64.39 percent. The results demonstrated that the use of Astragalus has been a profitable economic activity, which along with other rangeland products such as forage play an important role in the local economy and the area. In addition to creating jobs, it reduces the degradation and conversion of pastures to drylands. In addition, the economic investigation, particularly assessment and evaluation of market and non- market functions of rangelands can assist to better introduce the true value andfunctions of this resource as well as designing appropriate mechanisms for conservation and optimal utilization in all levels of management.

ABSTRACT Inthis study, allelopathic potential of Eucalyptus canaldulensis and sowing depth was studies on germination characteristics and vegetative growth of Onobrychis sativa seedlings using completely randomized design with four replications and two factors. The first factor was aqueous extracts of 1, 2, 3, and 5% of eucalyptus leaf powder in 1000 g of soil and the second factor was sowing depth in four levels including 0.5 as control, 1.5, 3, and 4.5 cm. Effect of allelopathic, sowing depth and their interaction on all traits but root length was significant. Effect of eucalyptus on shoot dry weight was more than other traits. On the whole, increasing in sowing depth had a negative effect on all traits and when allelopathy and sowing depth integrated, their negative effects were more significantly than their sole effects. Therefore, considering of allelopathy and sowing depth could have a determinative role in the eucalyptus growing lands.

The purpose of this study was to investigate the impact of blended learning and multimedia software on Iranian ESP student's vocabulary learning. To this end, 120 Iranian ESP learners were assigned to two groups: the experimental and control groups. The experimental group received instructions through multimedia software while the control group received traditional instructions. The data were collected through a vocabulary posttest and classroom observations. The results indicated the great level of disparity between the two groups of learners regarding their acquisition of new vocabulary - in other words, multimedia software had positive effect on student's vocabulary learning. In addition, learning with technology also showed positive activity engagement. Based on the current study, suggestions were made on how multimedia software can be adopted and incorporated more effectively in ESP classes.