• فهرس المقالات Steppe rangeland

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        1 - تغییرات گروه‌های عملکردی گیاهان در اثر آتش‌سوزی در مراتع نیمه استپی استان چهارمحال و بختیاری
        الهام بنی هاشمی علی اصغر نقی پوربرج
        زمینه و هدف: درک چگونگی پاسخ گیاهان به آتش‌سوزی برای پیش‌بینی ویژگی‌ها و پراکنش بسیاری از زیست بوم‌ها ضروری است. هدف این تحقیق شناسایی، طبقه‌بندی و تجزیه و تحلیل صفات عملکردی گیاهان است که بتوانند به عنوان وسیله‌ای برای شناسایی تغییرات جوامع گیاهی در اثر آتش‌سوزی در فوا أکثر
        زمینه و هدف: درک چگونگی پاسخ گیاهان به آتش‌سوزی برای پیش‌بینی ویژگی‌ها و پراکنش بسیاری از زیست بوم‌ها ضروری است. هدف این تحقیق شناسایی، طبقه‌بندی و تجزیه و تحلیل صفات عملکردی گیاهان است که بتوانند به عنوان وسیله‌ای برای شناسایی تغییرات جوامع گیاهی در اثر آتش‌سوزی در فواصل زمانی مختلف مورد استفاده قرار گیرند. روش بررسی: مطالعه حاضر در منطقه کرسنک در شهرستان بن و در استان چهارمحال و بختیاری انجام یافته است. تعداد 6 سایت با سابقه آتش‌سوزی یک‌ساله و پنج ساله انتخاب و نمونه‌برداری به روش تصادفی طبقه بندی شده انجام یافت. در هر پلات پس از شناسایی گونه‌های موجود، درصد پوشش هریک از گونه‌ها تخمین زده شد و صفات گیاهی اندازه‌گیری شدند. یافته ها: نتایج نشان داد که صفات گیاهی همچون ارتفاع گیاه، تولید، شاخص سطح برگ SLA، مساحت و وزن خشک برگ، درصد ترکیب گونه‌های گندمی، علفی و بوته‌ای، درصد ترکیب گیاهان با خوشخوراکی کلاس II و III، درصد ترکیب گونه‌های با اشکال زیستی همی‌کریپتوفیت و کامفیت در دو منطقه آتش‌سوزی و شاهد اختلاف معنی‌داری داشتند (05/0Sig ≤). طبق نتایج تحلیل مولفه های اصلی، تأثیرپذیرترین صفات به ترتیب عبارت از شاخص سطح برگ SLA، خوشخوراکی کلاس II، طول برگ، درصد ترکیب همی‌کریپتوفیت، درصد ترکیب پهن‌برگان علفی و مساحت برگ بودند که ارتباط مستقیمی با آتش‌سوزی پنج‌ساله و آتش‌سوزی یک‌ساله داشتند. بحث و نتیجه گیری: بنابراین می‌توان نتیجه‌گیری نمود که صفات گیاهی نقش مهمی در تعیین پاسخ گونه‌های گیاهی به آشفتگی‌های محیطی دارند و از این رو می‌توانند بر سیر توالی ثانویه مرتع نیمه استپی پس از آتش‌سوزی تأثیرگذار باشند. تفاصيل المقالة
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        2 - فنولوژی گونه‌های ‌Ferula ovinia و Poa bulbosa و بهترین زمان ورود و خروج دام در مرتع گوراب اصفهان
        مریم غلامی مصطفی سعیدفر
        زمینه و هدف: مطالعه فنولوژی یکی از عوامل مهم و اساسی در اعمال مدیریت جهت بهره برداری بهینه از پوشش گیاهی است. گونه های مرتعی Ferulaovinia وPoabulbosaاز نظر علوفه ای و مرتعی و همچنین جلوگیری از فرسایش خاک از اهمیت خاصی برخوردار هستند. این تحقیق به منظور تعیین زمان مناسب أکثر
        زمینه و هدف: مطالعه فنولوژی یکی از عوامل مهم و اساسی در اعمال مدیریت جهت بهره برداری بهینه از پوشش گیاهی است. گونه های مرتعی Ferulaovinia وPoabulbosaاز نظر علوفه ای و مرتعی و همچنین جلوگیری از فرسایش خاک از اهمیت خاصی برخوردار هستند. این تحقیق به منظور تعیین زمان مناسب ورود و خروج دام از مرتع، درسایت گوراب اصفهان در 35 کیلومتری غرب شهرستان فریدونشهر به مدت 4 سال (1395-1392) شده است. روش بررسی: در این تحقیق ده پایه انتخاب و اطلاعات مربوط به مراحل فنولوژی برای هر پایه در مقاطع زمانی 7 روزه در مرحله رویشی و 15 روزه در مرحله زایشی اندازه گیری و در فرم ویژه ای ثبت گردید. هم زمان آمار هواشناسی روزانه از ایستگاه هواشناسی مستقر در محل اجرای طرح برداشت شد. یافته ها: رشد رویشی گونه ovinia Ferulaاز اواخر اسفند آغاز و تا اواسط خرداد ادامه یافت. دوره گلدهی اوایل خرداد آغاز و تا اواخر خرداد به طول انجامید. مرحله رسیدن بذر از اواسط خرداد آغاز و تا اواخر تیر کامل شد. در گونه Poabulbosaرشد رویشی از اواخر اسفند شروع و تا اواسط خرداد ادامه داشت. دوره گل دهی از اوایل خرداد شروع و تا اواسط خرداد ادامه یافت. مرحله رسیدن بذر از اواسط خرداد شروع و تا اوایل تیر به پایان رسید. بحث و نتیجه گیری: نتایج نشان داد که با توجه به رفتار گونه های مورد مطالعه در بروز پدیده های زیستی در سال های مختلف مطالعه این امکان فراهم شده است که رفتار گیاهان را با تغییرات رطوبتی و دما در شرایط مختلف بررسی کنیم. بهترین زمان و ورود و خروج باید براساس نحوه بروز پدیده های زیستی در گونه ی Poa bulbosa تنظیم شود که در این صورت براساس مطالعات انجام یافته بهترین زمان می تواند در آخر اردیبهشت و اوایل خرداد باشد و زمان خروج دام به علت وجود پایه های خشک شده به ویژه در گونه ی Ferula ovina که در زمان خشک شدن (شروع تابستان) مورد استفاده دام قرار می گیرد، می تواند تا اواسط شهریور (مشروط بر رعایت تعداد دام مبتنی بر ظرفیت مرتع)، ادامه یابد. تفاصيل المقالة
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        3 - Changes in Soil Properties by Harvester Ant's Activity (Messor spp.) in Roodshoor Steppe Rangeland of Saveh, Iran
        Mahsa Ghobadi Mohammad Mahdavi DONAT AGOSTI
        One of the most important micro engineers of the terrestrial ecosystems, especially in the arid areas is the harvester ants due to their activity in the soil through nest building; they can make major changes while influencing the surface and subsurface in the rangeland أکثر
        One of the most important micro engineers of the terrestrial ecosystems, especially in the arid areas is the harvester ants due to their activity in the soil through nest building; they can make major changes while influencing the surface and subsurface in the rangeland soil. The purpose of this study was to investigate the effects of harvester ants (Messor spp.) on some soil properties in Roodshoor Steppe rangeland in Saveh, Iran. Soil samples in four depths (0-10, 10-20, 20-30, and 30-40 cm) were taken in three treatments of active and non-active nests and control area. Soil infiltration test was carried out over ants' nest and control site in dry and wet seasons by double rings method. The results showed that the Messor spp. soils had lower pH and higher concentration of organic matter, total carbon, N, P, K, Mg+2, Ca+2, Ec and sand percent in comparison with the control site. The soil infiltration rate regarding the nests was significantly higher than the control area in both dry and wet seasons. In the same habitat, nutrient concentrations did not change along the vertical gradient in contrast to control plots where soil nutrients decreased with depth. This showed homogeneity of different soil layers by ants. On the other hand, investigating the chemical and physical properties of soil did not show a significant difference between the dead nests and the control area. This can be the expression of effects created as the result of the presence of ants in modifying soil in the active nests. These effects disappeared with the passage of time after they left their nests. Therefore, the role of the ants in changing soil properties should be considered, especially in the arid and semi-arid area in which the soil is poor. The presence of ant colonies and their activity in this climate can improve soil conditions and increase soil fertility in most parts of the ground. تفاصيل المقالة
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        4 - Determining Timely Entry and Exit of Livestock in Rangelands Using Bromus tomentellus Phenological Stages (Case Study: Goorab Rangeland of Isfahan)
        Maryam Gholami Mostafa Saeedfar
        In the rangelands of Iran, the lack of appropriate grazing management is one of the major problems ultimately leading to untimely and excessive grazing intensity of forage. Accordingly, most of the rangelands show a retrogression trend and poor conditions. In forage spe أکثر
        In the rangelands of Iran, the lack of appropriate grazing management is one of the major problems ultimately leading to untimely and excessive grazing intensity of forage. Accordingly, most of the rangelands show a retrogression trend and poor conditions. In forage species, phenological stage is one of the most important criteria for range management. Bromus tomentellus species is an important range species for forage production controlling soil erosion. In order todeterminethetimely entry and exit of livestock in rangelands based on phenological stages of B. tomentellus, this study was conducted in Goorab rangeland, Fereydoun Shahr, Iran during four years (2007-2010). In this research, ten plant bases of B. tomentellus were selected and their phonological stages were recorded in a 7-day interval period. At the same time, meteorological data were collected from meteorological station adjacent to the study site. According to the occurrence of biological phenomena in the different years of study (wet conditions in 2007, severe droughts in 2008 and normal years in 2009 and 2010) and also based on plant growth stage in the 4 year study, it was concluded that 30th April and 31th May were suggested as the best time for livestock to enter and exit from the rangeland, respectively. تفاصيل المقالة
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        5 - Role of Plant Species and Ecological Patches in Conserving and Fixing Natural Landsʹ Soil Using Landscape Functional Analysis (LFA) (Case Study: Dehbar Rangeland, Torghabeh, Mashhad, Iran)
        Reyhaneh Azimi Gholam Ali Heshmati mohamad kia kianian samira hossein jafari Dawood Zakeri
        Degradation of plant patches is considered as one of the indices for rangeland degrading health condition. Investigating the accuracy of triple indices (infiltration, stability and soil nutrient cycle) presented by LFA method seems necessary to determine its efficiency أکثر
        Degradation of plant patches is considered as one of the indices for rangeland degrading health condition. Investigating the accuracy of triple indices (infiltration, stability and soil nutrient cycle) presented by LFA method seems necessary to determine its efficiency in semi-arid areas with the least cost. This study aims to investigate the role of vegetative species and growing forms on soil surface characteristics in Dehbar semi-steppe rangelands, Iran in 2014. So, eleven soil surface characteristics in different vegetative types each of 3 replicates were measured using landscape functional analysis (LFA). Then, the measured parameters were classified based on their sustainability, permeability and food chain continuum for each plant species. According to the results obtained from various analytical investigations, the ecological patches consisting of Artemisia aucheri (46.83%) and complex of Artemisia aucheri and Agropyron intermedium (with the amount of 41.7%) were higher than other forms of vegetative growth for soil sustainability. The complex of Acantholimon sp., Artemisia aucheri and Astragalus commixtus had the lowest amount in terms of soil sustainability (38%). The comparison of soil permeability indices for different types of plant covers showed that the percentage of Artemisia aucheri (32.06%) and complex of Artemisia aucheri and Agropyron intermedium (33.5%) had the highest amount while all other patches were equal and had the lowest amount. In terms of food chain, the ecological patches such as Artemisia aucheri (25.63%) and complex of Artemisia aucheri and Agropyron intermedium (27.66%) had the highest amount. The complex of Artemisia aucheri and Astragalus commixtus (16.36%), the complex of Acantholimon sp., Artemisia aucheri and Astragalus commixtus (13.63%) and the complex of Acantholimon sp. and Agropyron intermedium (15.36%) had the lowest values (p≤0.01). Therefore, Artemisia aucheri (shrub) and a complex of Artemisia aucheri and Agropyron intermedium (grass) patches, introduced as ecological indicators for the study area, are suggested for rangelands restoration. تفاصيل المقالة
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        6 - Investigation of Climatic Parameters Affecting Annual Forage Production in BidAlam rangeland, Abadeh, Fars Province, Iran
        Hossein Arzani Eshagh Omidvar Saeed Mohtashamnia Seyed akbar Javadi Mohammad Jafary
        Regardless the crop production, range and livestock management is unlikely to be possible. Considering the range production is essential for efficient and effective range management. This study aims to investigate the relationship between the rate of forage production a أکثر
        Regardless the crop production, range and livestock management is unlikely to be possible. Considering the range production is essential for efficient and effective range management. This study aims to investigate the relationship between the rate of forage production and the effects of climate variables. For this purpose, forage yield of four range species including Artemisia sieberi, Scariola orientalis, Stipa atriseta, and Stachys inflate regarded as indices species was recorded in Bidalam rangeland, Fars province, Iran in a 10-year period (1998 to 2007) and then, the study continued for another two years (from 2016 to 2017). Forage yield was collected through cutting and weighing method in 60 random 2m2 plots along four 300 m transects during 12 years. Climatic parameters such as rainfall, temperature, relative humidity and sunshine periods were obtained from Abadeh weather station and used for estimation of forage yield in different growth periods of the year. The annual dry matter production of each species and sum of all species were used as dependent variables and climatic parameters were considered as independent ones using multivariate linear regression. The results showed that previous rainfall (rainy of growing season plus last year) had the highest effect on annual forage production of rangelands (R2=0.88). It was concluded that using regression analysis between annual rainfall and forage production in some indices species, the rangeland production of coming years could be estimated with high accuracy. تفاصيل المقالة
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        7 - Changes in Vegetation and Soil Characteristics of Steppe and Semi-Steppe Rangelands under Impact of Solar Power Plant in Absard and Shahrerey, Iran
        Mahshid Souri Nadia kamali
        In recent years, Iran has begun to move towards the development of the use of renewable energy sources in line with global developments. In this study, Side effects of two solar power plants on rangeland condition were studied. These solar power plants have been constru أکثر
        In recent years, Iran has begun to move towards the development of the use of renewable energy sources in line with global developments. In this study, Side effects of two solar power plants on rangeland condition were studied. These solar power plants have been constructed using mosaic panels for installation obliquely on 16 ha in Absard rangeland (semi-steppe) and 23 ha in Shahrerey rangeland (steppe), Iran in 2016. In this study, sampling was performed in both rangelands for solar power plant and adjacent control. Sampling was done in 2019, based on the use of 100 m transects with one and two square-meter plots for semi-steppe and steppe, respectively, with a distance of 10 m on transects, systematically. Soil samples were taken from a depth of 0-30 cm from the beginning, middle and end of each transect as a composite sample. The obtained data were compared using independent T-test by SPSS software. Results showed that in comparing of soil factors between solar power plant and adjacent control site in both rangelands, there were no significant differences between treatments. However, vegetation cover and total biomass between solar power plant and control in Absard were significantly different (P<0.01). In Absard site, the vegetation cover (39% vs. 51%) and total biomass with values of (254 vs. 312 kg/h) were obtained in solar power plant and control, respectively, so the panel significantly reduced the performance of the vegetation cover and biomass in semi-steppe rangeland. In contrast, In Shahrerey , the vegetation factors between the solar power plant and the control were not significantly different from each other. So, from the point of view of natural resources and according to the results of the present study, for electricity generation, the establishment of solar power plant in the steppe rangelands is recommended as compared to semi-steppe rangeland. تفاصيل المقالة
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        8 - Evaluation of Meteorological Factors in Estimating Forage Production in Steppe and Semi‌-steppe Rangelands of Iran
        Hossein Arzani Zahra Mansouri Aliraza Moghaddamnia Javad Motamedi Shahram Khalighi Sigaroudi
        Rangeland production is especially important in meeting food requirement of rangeland societies. Sometimes, historical data are required for long-term grazing capacity estimation. Regression equations that are reasonably reliable for predicting forage production from pr أکثر
        Rangeland production is especially important in meeting food requirement of rangeland societies. Sometimes, historical data are required for long-term grazing capacity estimation. Regression equations that are reasonably reliable for predicting forage production from precipitation characteristics have been developed for rangeland yield estimation. In this research, the relationship between forage production and meteorological factors was evaluated with six-year data for Pashaylogh and Incheboron rangelands (2003 to 2007 and 2017- Golestan province, Iran) and eleven-year data for Nemati rangeland (1998 to 2007 and 2017- Markazi province, Iran). For sampling, four parallel transects with a length of 300 m and at a distance of 100 m from each other were established in the steppe area (Nemati) and six 200-m transects were created in the semi-steppe area (Pashaylogh and Incheboron) and they were located parallel and at a distance of 100 m from each other. Due to the need for uniformity in the data of the rangelands of different provinces and their comparison, plot size of 1×2 m was selected in steppe site, and 1×1 m for semi-steppe sites. Data analysis was done through regression models. The results showed that forage production was related to temperature and precipitation rather than other meteorological factors (temperature, precipitation, sunlight hours, relative humidity, evapotranspiration and average wind speed). The best equation that can predict the relationship between meteorological data and forage production was August precipitation and temperature (R2=0.88) in Pashaylogh, the precipitation of June (R2=0.88) in Incheboron rangelands. There was a relationship between forage production (R2=0.79) with precipitation and temperature in July and in Nemati rangeland. The forage production index was determined based on effective meteorological factors and The Standardized Precipitation-Evapotranspiration (SPEI) drought index. According to meteorological data, a coefficient could be obtained to estimate long-term rangeland production and prevent from forage loss. تفاصيل المقالة
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        9 - Effects of Phenological Stages on Yield and Quality Traits of Three Halophyte Plant Species as Forage Sources and Combating Desertification in Khuzestan Province, Iran
        Kourosh Behnamfar Ehsan Zandi Esfahan Ali Ashraf Jaffari
        Halophytes have good potential for forage production and combating desertification in saline soils. The present research was aimed to investigate the effects of phenological stages (Vegetative, Flowering & Ripening) on the yield and quality of three halophytes, Atriplex أکثر
        Halophytes have good potential for forage production and combating desertification in saline soils. The present research was aimed to investigate the effects of phenological stages (Vegetative, Flowering & Ripening) on the yield and quality of three halophytes, Atriplex leucoclada, Suaeda fruticosa, and Seidlitzia rosmarinus, in warm steppe rangelands, Khuzestan privince, Iran. Data were collected in 2015-2016 for Dry Matter (DM) yield. Quality traits included Crude Protein (CP), Dry Matter Digestibility (DMD), Water-Soluble Carbohydrates (WSC), Acid Detergent Fiber (ADF), Crude Fiber (CF), Neutral Detergent Fiber (NDF), and total ash. Data were statistically analyzed using SAS9 software and means were compared using LSD 5% method. Results showed a significant difference between species, phenological stages, and their interaction for all the traits. S. fruticosa and A. leucoclada with average values of 14.45 and 12.88 t/ha had higher and lower production, respectively. In all species, with some exceptions, the DM yield, WSC, ADF, CF, and NDF increased, and CP, DMD, and ash decreased with the development stages. For S. rosmarinus, the lower and higher DM yield with values of 8.11 and 16.90 t/ha were obtained in the vegetative and flowering stages, respectively. The highest and lowest CP in S. fruticosa (17.73 and13.31%), S. rosmarinus (13.05 and 9.62%), and A. leucoclada (10.19 and5.29%) were obtained in flowering and seed ripening stages, respectively. In S. rosmarinus, DMD decreased in the flowering stage compared to the vegetative stage (from 70% to 65%), but its value increased again in the seed production stage and reached to 90%. However, in Suaeda and Atriplex, there was no significant variation at different growth stages. Our results clearly showed that Suaeda fruticosa having a higher DM yield in the flowering stage (16.20 t/ha) coupled with higher CP (18.04%) (p<0.5) recommended for cultivation as forage sources and combating desertification in Khuzestan province, Iran. تفاصيل المقالة
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        10 - Effects of Shrub Canopy on the Microclimate and Soil Properties of Steppe Rangeland
        Tahereh Sadeghi Shahrakht Mohammad Jankju Mansour Mesdaghi
        In arid and semi-arid ecosystems, shrubs may act as fertility islands but theireffect may vary depending on their morphology and ecological impacts. This research wasaimed to study effect of three shrubs Scariola orientalis, Astragalus heratensis, and Rosapersica on soi أکثر
        In arid and semi-arid ecosystems, shrubs may act as fertility islands but theireffect may vary depending on their morphology and ecological impacts. This research wasaimed to study effect of three shrubs Scariola orientalis, Astragalus heratensis, and Rosapersica on soil properties and on the microclimate conditions (temperature, luminance, andsoil moisture) of their understory in the steppe rangelands of Kakhek Gonabad, Iran. Along50-m transects, flexible plot sizes were selected to measure the microclimate factors ofunderstory species and the open spaces next to the shrubs based on the canopy diameters ofeach intercepted shrubs. Soil samples were taken from understory of shrubs. Themicroclimatic factors of understory and open spaces were compared using paired-t test.The soil properties were analyzed under 3 shrubs and open spaces and then comparisonwere made using Duncan‟s test. The results showed that temperature and luminanceintensity were significantly lower in understory than the open spaces (p<0.05). Soil depthmoistures (15-55 cm) were higher in understory than the open space while soil surfacemoistures (0-10 cm) did not vary. Among the investigated shrubs, Astragalus heratensishad the greatest facilitation effect on microclimatic factors. The soil criteria of EC (0.32mS/cm), organic matter (1.6%), and nitrogen (0.08%) were significantly higher inunderstory of Astragalus heratensis than in the open space (0.15 mS/cm, 0.39%, and0.028%), respectively. These effects can be related to the wider canopy cover, greaterstature, and possibly nitrogen fixation for Astragalus heratensis. تفاصيل المقالة