ِAli Tavili; S. Motahareh Hosseini; Mohammad Jafari; Ali Golkarian
Abstract
MAXENT model was used to evaluate the probability of Dorema ammoniacum development in rangelands of Southern Khorassan. Presence data of D. ammoniacum was recorded based on field survey and GPS application. Nine environmental information layers were used to model potential habitat of the understudy species. ...
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MAXENT model was used to evaluate the probability of Dorema ammoniacum development in rangelands of Southern Khorassan. Presence data of D. ammoniacum was recorded based on field survey and GPS application. Nine environmental information layers were used to model potential habitat of the understudy species. Relationship between species presence and environmental parameters was determined using maximum entropy. Map of species distribution was achieved. Results showed that the probability of D. ammoniacum is higher in regions with the following environmental characteristics; elevation of 1017-1933 m, average temperature of 13.96 to 15.17 ºC, average precipitation of 112- 131 mm, slope of 0-14% and LST range between -4 to 10 ºC. An AUC of 92 demonstrated that MAXENT is a suitable model for prediction of D. ammoniacum distribution and potential habitat.
Moselm Rostampour
Abstract
This study compared of univariate outlier detection methods among vegetation data in a study of the effect of grazing intensity in the rangelands of arid regions. For this purpose, after measuring the vegetation cover in the rangeland and before the statistical analysis, the presence of outlier data ...
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This study compared of univariate outlier detection methods among vegetation data in a study of the effect of grazing intensity in the rangelands of arid regions. For this purpose, after measuring the vegetation cover in the rangeland and before the statistical analysis, the presence of outlier data was examined as the assumption of parametric comparison tests. In this study, eight methods including the boxplot and IQR (Tukey method), standard deviation of the mean (three-sigma rule), median absolute deviation (Hampel method), trimmed mean, 1st percentile and 99th percentile, The Chi Square test (χ²), the Grubbs Test (ESD) and the Rosner test (generalized ESD) were used. The results showed that the vegetation cover of rangelands with light and moderate grazing intensity was not normally distributed (Shapiro-Wilk test: p≤0.05). Even deletion of outliers did not lead to a normal distribution, but it resulted in the homogeneity of variances (Levene's test: p≥0.05). The modified Z-score and the Grubbs and Rosner tests (p≥0.05) did not identify outliers from the vegetation cover data. Among the methods evaluated, the boxplot and MAD method, which are not dependent on the mean, are more suitable for the vegetation cover. Therefore, before performing any comparison test, a combination of visual and statistical methods is recommended to evaluate the presence of outliers.
Mohsen Kazemi; Elias Ibrahimi Khorram Abadi
Abstract
Khorasan Razavi province has several rangeland species that their nutritive value is still unknown for the animal husbandman. Hence, this experiment was conducted to determine the nutritional potential of some range species containing Carthamus oxyacantha, Echinops ilicifolius, Silybum marianum, and ...
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Khorasan Razavi province has several rangeland species that their nutritive value is still unknown for the animal husbandman. Hence, this experiment was conducted to determine the nutritional potential of some range species containing Carthamus oxyacantha, Echinops ilicifolius, Silybum marianum, and Eremurus luteus (at the flowering stage) with a completely randomized design in 2019. The chemical-mineral compositions, gas production parameters, buffering capacity, and some ruminal fermentation parameters were determined in vitro. The lowest neutral detergent fiber (NDF, 16.41%), acid detergent fiber (ADF, 12.82%), acid detergent lignin (ADL, 5.52%), and crude fiber (CF, 17.63%) contents were obtained in Eremurus luteus (p < 0.0001). The highest crude protein (CP, 19.88%) and ash (21.69%) contents were observed in Silybum marianum (p < 0.0001). Higher calcium (Ca, 30.42 g/kg DM) content was observed in Eremurus luteus (p < 0.0001). The highest contents of nitrogen, potassium, sodium, magnesium, iron, zinc, manganese, and cobalt were related to Silybum marianum (p < 0.0001). Metabolizable energy (ME) ranged from 6.48 for Carthamus oxyacantha to 9.84 MJ/kg DM for Eremurus luteus. Eremurus luteus exhibited the highest (p < 0.0001) dry matter digestibility (DMD, 73.15%) and acid-base buffering capacity (213.05 mEq×10-3). The pH of the plant also ranged from 5.36 for Eremurus luteus to 6.05 for Echinops ilicifolius. The present study showed that each of the four rangeland species can easily meet part of the maintenance requirements of ruminants for nutrients and minerals. According to the measured parameters, Eremurus luteus had the highest nutritive value compared to the other plants.
Hamid Jamali; Ataollah Ebrahimi; Elham Ghesareh Ardestani; Fatemeh Pordel
Abstract
Density is an important indicator of vegetation evaluation, which several methods have been developed for its assessment, but their accuracy is concerned. To reveal accuracy of each methods, a study site of 32000-m2 in the steppe rangeland of Marjan, Boroujen was selected and divided into eight macroplots ...
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Density is an important indicator of vegetation evaluation, which several methods have been developed for its assessment, but their accuracy is concerned. To reveal accuracy of each methods, a study site of 32000-m2 in the steppe rangeland of Marjan, Boroujen was selected and divided into eight macroplots of 4000-m2. Then, the individuals of Astragalus verus and Astragalus albispinus were counted in each microplots. A transects of 100-m established parallel to the length of the macroplots (40 × 100 mm) and density was measured using closest individual, nearest neighbor, random pairs, point-centered quarter, third closest individual, angle order and variable area transect methods, systematic-randomly in 10 sampling points in each macroplots. The results indicate that the real density of A. verus and A. albispinus were 0.1593±0.084 and 0.0622±0.0282/m2, respectively. Closest individual (0.1357±0.1315/m2), nearest neighbor (0.1368±0.1432/m2), point-centered quarter (0.1016±0.1664/m2), random pairs (0.0588±0.0536/m2), third closest individual (0.1107±0.0775/m2) and variable area transect (0.0221±0.0105/m2) for A. verus and angle order (0.0927±0.0523/m2), nearest neighbor (0.0424±0.0357/m2) and third closest individual (0.0524±0.0447/m2) for A. albispinus showed no significant difference with controls. The results revealed that the closest estimation to the controls belongs to the nearest neighbor (-0.141) and third closest individual (-0.0098) for A. verus and A. albispinus, respectively. Moreover, the nearest neighbor (RMSE=0.6877, SE=0.0026 and R=0.1147) and closest individual (RMSE=0.5609, SE=0.0007, R=0.0320) showed the most precise estimation of densities of A. verus and A. albispinus, respectively. Generally, the closest individual for estimating plant density of A. verus and the nearest neighbor's for A. albispinus are proposed.
Shima Javadi; Gholamreza Zehtabian; Mohammad Jafari; Hassan Khosravi; Azam Abolhasani
Abstract
The reduction of soil quality and health due to the lack of proper management or land use change in arid and semi-arid regions of Iran has become a major challenge, which affects the nutritional properties of the soil. Regarding to the importance of nutrients in plant growth, the aim of this study was ...
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The reduction of soil quality and health due to the lack of proper management or land use change in arid and semi-arid regions of Iran has become a major challenge, which affects the nutritional properties of the soil. Regarding to the importance of nutrients in plant growth, the aim of this study was investigation and comparison of soil nutrients under different agricultural land uses in Eshtehard region. At first, different maps of region including soil map, elevation and land use maps were prepared using ArcGIS 9.3. Five land uses including garden lands, monoculture lands, multiple cropping lands, fallow lands and rangelands were recognized as the treatments. After sampling the soil, nutrients including N, Ca, Mg, K, P were measured in two depths of 0-30 cm and 30-60 cm. In addition, the amount of ESP, as a destructive factor, was assessed in order to determine the corrective or destructive role of different land uses. The results of statistical analysis of data using SPSS software showed that there was a significant difference between nutrients average. In addition, the results showed that rangelands and garden lands had the corrective role in surface and deep layers respectively and monoculture lands had destructive role in the deep layer. Follow lands had the most destructive role in both surface and deep layers. Generally, garden lands, rangeland and multiple cropping lands were determined as the most desirable treatments and follow lands and monoculture lands were determined as the most undesirable treatments.
hamid barghi; Bahman Shafiei; ahmad hajarian
Abstract
The present study was conducted using analytical-descriptive methods with the aim of investigating the limitations and abilities of using the rangelands of Kermanshah province by Dehyar using AHP and SWOT models. The statistical population consisted of experts from the Natural Resources Bureau of 14 ...
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The present study was conducted using analytical-descriptive methods with the aim of investigating the limitations and abilities of using the rangelands of Kermanshah province by Dehyar using AHP and SWOT models. The statistical population consisted of experts from the Natural Resources Bureau of 14 people. The tool used to collect the data was a questionnaire which was designed according to the review of the field of research and individual interviews with the experts of the Natural Resources Bureau of the region. Data collected using SWOT and AHP model have been investigated. The results indicated that the most important points in the field of exploitation of rangelands in Kermanshah province are determining the appropriate season and grazing time in rangelands with a weight score of 0.96, the most important weakness, non-principled exploitation of rangelands with a weight score of 1.04, the most important opportunity , The beginning of activities for preserving rangelands in Kermanshah, such as seeding of rangeland species proportional to climate, soil and ... with a weight score of 1.02, and the most important threat is the lack of precise monitoring and strong management of the unit in maintaining pasture and inter-system coordination with a weight score of 0.80. Also, in the prioritization of strategic factors based on the AHP model, it was observed that the most important non-principle exploitation of rangelands with a weight of 0.289 and then the beginning of conservation activities in Kermanshah, such as seeding of rangeland species proportional to climatic, soil and
nayefe adak; Hossein Arzani; Sayed Mahdi Heshmatol vaezin
Abstract
Beekeeping is one of the agricultural production activities that can create employment with a small amount of investment. Beekeeping can be heeded as one approach to increase stakeholder’s income of rangelands, balance between livestock and rangeland resources, enhancing the economic status of ...
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Beekeeping is one of the agricultural production activities that can create employment with a small amount of investment. Beekeeping can be heeded as one approach to increase stakeholder’s income of rangelands, balance between livestock and rangeland resources, enhancing the economic status of the villagers and participation in range management plans. Zhiwar rangelands have great potential of land uses variety .Therefore in this study, we decided to determine the amount of increasing income from beekeeping. some of the factors that can affect the income of beekeepers were studied in this research. some of this factors include individual traits of beekeepers, the unit traits of beekeeping, the Costs, incomes. the datas of questionnaires in this study were collected by interview and filling out questionnaires. Questionnaire analysis was performed by using SPSS software. The results showed that the number of hives, the ratio of sugar to honey had significant impacts on the income of beekeepers and honey production. Among whole costs, sugar had the greatest proportion which causes decreasing in prices and thus, profitability. On one side the Increase of the percentage, causes the ascendancy in production and income, on the other side, it causes reducing in the costs and increasing in expenses. Thus, reducing the profitability is not only because of the high consumption of sugar, it may be also due to poor marketing. But the number of hives due to reducing average costs causes increasing profitability
Bakhtiar Fattahi; Mohammad Jafari; Soheila Aghabeigi Amin; mahdieh salehi; ayoub karimi; Azad Karami
Abstract
Abstract This study aimed to investigate the effect of different intensities of grazing on soil chemical properties on Gonbad paired basins-Hamadan. The objective of this research was to characterize the impact of sheep grazing intensity on soil chemical behavior on mountainous in Hamadan rangelands ...
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Abstract This study aimed to investigate the effect of different intensities of grazing on soil chemical properties on Gonbad paired basins-Hamadan. The objective of this research was to characterize the impact of sheep grazing intensity on soil chemical behavior on mountainous in Hamadan rangelands (Gonbad paired basins). Grazing intensity was classified as light, moderate and heavy, then the soil samples from the three depths of 0-10, 10-20 and 20-30 cm were collected. The soil data was analyzed via SPSS (ANOVA). Results showed that the soil OC, total N content and organic matter decreased significantly with grazing intensity and they were greatest at the surface and decreased with depth. The amount of Calcium and Magnesium won't be affected by grazing intensity. The decreases in soil OC suggest Carbon storage in the soil of grassland declined as grazing intensity increased. Combined with the decreases in soil TN content, this also means heavy grazing could lead to decreases in soil quality and fertility. Uneven grazing intensity is an inherent feature of a season long-grazing system and there are risks to avoid quality and environmental health.
mahdie mahmoodi; Ataollah Ebrahimi; Mohammad Hasan Jouri; pejman tahmasebi
Abstract
The evaluation of utilization of key species is cornerstone of decision-making in rangeland management. Measuring utilization is essential for regulating grazing intensity, grazing pressure and distribution of animals. utilization of two key grass species of Dactylis glomerata and Bromus tomentosus, ...
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The evaluation of utilization of key species is cornerstone of decision-making in rangeland management. Measuring utilization is essential for regulating grazing intensity, grazing pressure and distribution of animals. utilization of two key grass species of Dactylis glomerata and Bromus tomentosus, as two important rangeland species is determined using height-weight relationship. The research is done in two vegetative periods of prior to flowering and flowering stages in two region of grazing land and exclosure by 32 transects of 100-meter length. To do so, the height of species was measured and cut at 1-cm above soil surface and weighted freshly. The samples are clumped and moved to the laboratory and oven dried at 65°c after separating litter divisions Then, the whole individual plants were weighted and cut in 5-cm intervals and each part was re-weighted and recorded separately for each species. Height-weight relationships were analyzed by different regression models in SPSS v.18 software. Result shows that sigmoid model significantly illustrate the height-weight relationship of both species of Dactylis glomerata and Bromus tomentosus with R2=0.994 and 0.997 at prior to flowering stage in the exclouser respectively. Similarly, sigmoid model also elucidate the height-weight relationship of both species of Dactylis glomerata and Bromus tomentosus with R2=0.975 and 0.998 at the flowering stage in the exclouser, respectively. The sigmoid model also best fitted for depicting height-weight relationship of both species at prior to flowering stage in grazing land for both species with R2=0.996, too.
ّFarhad Azhir; Mohammad Fayaz
Abstract
It was necessary to detect Technical knowledge for advising culturing various plant species which share in production forage rangelands depend on region condition. Vicia subvillosa species seeds were collected from ranges around road direction Azadshahr city toward Shahrood city, on 1900 meter height ...
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It was necessary to detect Technical knowledge for advising culturing various plant species which share in production forage rangelands depend on region condition. Vicia subvillosa species seeds were collected from ranges around road direction Azadshahr city toward Shahrood city, on 1900 meter height level form sea, and planted. The goal was to introduce the suitable season and method for cultivating this species in rangeland area. Experiment was performed on Telmadare area in Posht-kooh water spreading station with 350 mm. precipitation and semi dry cold climate. Main treatments include autumn and spring, sowing date, and two subsidiary treatments seedling and planting seed, by split plot completely randomize block design in three repetition were compared. Result showed that there was a significant deference between spring and fall date cultivation, and also between two subsidiary seedlings and planting seed. Seed Germination and survival at growing period in fall season (Germination 30.50%, survival 20.97% ) compared to spring (Germination 21.50%, survival 15.33% ) and planting seed (Germination 32.61%, survival 22.39% ) compared to seedling (Germination 21.39%, survival 13.92% ) were preferred. So with Vicia subvillosa cultivation is possible to produce forage in experimental Station case, and similar climatic ecosystem area.
Reza midipour; Reza Erfanzadeh; Marzban Faramarzi
Abstract
Intensive livestock grazing is one of the most important destructive factors in rangelands that leads to decrease of diversity and causes disappearance of sensitive plants. On the other hand, considering the scales in assessment of diversity is very importance to study the variability of plant diversity ...
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Intensive livestock grazing is one of the most important destructive factors in rangelands that leads to decrease of diversity and causes disappearance of sensitive plants. On the other hand, considering the scales in assessment of diversity is very importance to study the variability of plant diversity patterns in different scales. Therefore, current study aimed to investigate the impact of livestock grazing on diversity components in different scales using additive partitioning methods in western country rangelands in the Ilam province. Sampling was carried out in 40 plots of 4m2 in 8 rangeland sites including 4 exclosures and 4 grazing sites. Based on additive partitioning diversity methods, the total diversity was partitioned into additively components within and among samples. The results showed that diversity among sites (β2) had the highest contribution of total diversity that indicated the importance of this scale for conservation practices, and it was due to the variation of composition between sites. In addition, the results represented that exclosure in the semi-arid areas can increase diversity at plot scale, while in the regional scales (diversity among sites or β2) livestock grazing leads to increase in diversity. Therefore, exclosure of rangelands does not necessarily lead to increase in diversity. Also, long terms exclosure can lead to increase evenness that resulting in increasing competition among plants, therefore it could decrease plant diversity.
Ataollah Ebrahimi
Abstract
Canopy cover and forage production have always been two important indicators in rangeland assessment, which sometimes are applied as surrogates of each other. These two indicators are widely used in rangeland studies and have a vital role in evaluation of rangeland structure and functions. Occasionally, ...
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Canopy cover and forage production have always been two important indicators in rangeland assessment, which sometimes are applied as surrogates of each other. These two indicators are widely used in rangeland studies and have a vital role in evaluation of rangeland structure and functions. Occasionally, different sampling groups (estimators) evaluate forage production and canopy cover of different spaces and times. This research was aimed at investigation of different sampling groups and life-forms' effects on relationship between canopy cover and forage yield estimation. To do so, the impact of three sampling groups and five life forms (Fixed factors) on estimation of relationship between canopy cover (covariate) and forage yield (dependent variable) in a full factorial model in rangeland of Chahrtagh of Naghan, Chahrmhal-va-Bakhtiari Province, was estimated. Results shows that predictor variable of canopy cover is a god surrogate for forage production (P≤0.05) of different life-forms, but different sampling groups significantly (P≤0.05) effects on relationship between canopy cover and forage production estimation. Nevertheless, different life-forms do not significantly (P≤0.05) influence estimation of canopy cover and forage production relationship. By the way, interaction between sampling group and life forms considerably (P≤0.05) affects the relation. Therefore, we conclude that, although, the canopy cover is a good predictor of forage production, nonetheless, different sampling groups should not be engaged in sampling and monitoring vegetation cover and forage production estimation, specifically, if estimation of different life-forms' production is intended.
Ghader Karimi; Hasan Yeganeh; hasan barati
Abstract
Rangelands have been composed of different plant species that emergence of phenological stages in every one of them will be influenced by environmental and genetic factors. In order to exploit the time and achieve acceptable performance in each plant species, it is necessary that the emergence of biological ...
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Rangelands have been composed of different plant species that emergence of phenological stages in every one of them will be influenced by environmental and genetic factors. In order to exploit the time and achieve acceptable performance in each plant species, it is necessary that the emergence of biological phenomena are recorded and studied. The objective of the present study is to survey the different phenological stages of Bromus tomentellus in order to achieve proper management programs in the study area and similar areas. For this purpose, this study was conducted in semi- steppe rangelands of Kordan located in Alborz province for a 4-year period (2007- 2010). Among the plant species under consideration, ten plant bases were selected and recorded in special forms, during 4 years in the growing season, in 15-day intervals at the vegetative stage and in weekly intervals at reproductive stage, occurrence date of plant critical stages including the stages of the growth and vegetative growth, flowering, seed maturation and drying of the plant, along with the information related to the total height of plant in centimeter. In addition, the meteorological data and information relevant to a four- year study include; average monthly temperature and monthly rainfall from the meteorological station closest to the study area were prepared, and by noting the dry period, the Ombrothermic curves for the years 2007-2010 were separately drawn to adapt to the phenological stages of the study plant. The results indicated that this plant species begins its growth by noting the weather conditions, especially environment temperature (degree-day), in different years of the study period. Different phenological stages also have almost constant temperature demand (GDD), which the emergence of the stages is observed after obtaining the required temperature
Leila Fazel Dehkordi; Hossein Azarnivand; Mohammad Ali Zare Chahouki; Farhad Mahmoudi Kohan; Shahram Khalighi Sigaroudi
Abstract
To identify an appropriate index for monitoring and evaluation of drought, rainfall data obtainedfrom meteorological stations of Ilam Province from 2000 to 2011 and MODIS satellite images with16-day intervals were collected and processed. The Standardized Precipitation Index (SPI) wascalculated based ...
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To identify an appropriate index for monitoring and evaluation of drought, rainfall data obtainedfrom meteorological stations of Ilam Province from 2000 to 2011 and MODIS satellite images with16-day intervals were collected and processed. The Standardized Precipitation Index (SPI) wascalculated based on rainfall data; therefore, the rainfall data were used for measuring SPI andsatellite images were used for calculating NDVI. Also, the percentages of canopy cover in rangetypes were selected from the information of the National Evaluation of rangelands in differentclimatic zones. The correlation between SPI and NDVI and also canopy cover and NDVI wasexamined. The relationship between vegetation index (NDVI) and SPI was determined byregression. The results of SPI showed that in 2000 a severe drought and in 2006 a medium wetoccurred in rangelands of Ilam Province. NDVI value variations have as well confirmed it. Theresults showed that NDVI and life form (annual forb and annual grass) has the highest percentage ofcorrelation. Also examining of result showed that most correlation of SPI and NDVI was in 3 and 6-months intervals. Evaluation of regression models performance in range types described thatmodels in 3 and 6- months intervals was suitable for monitoring drought. The result of regressionconfirmed that NDVI was an appropriate index for monitoring and assessment of drought.
Sana Mohebbi; Ghasem Ali Dianati Tilaki; Mehdi Abedi
Abstract
Assessment of rangeland ecological characteristics have been proposed as an important factor inreviewing and monitoring the effects of various management measures and it demands differenttools for quantifying and offering a reasonable criterion for comparison of different managements.For this purpose, ...
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Assessment of rangeland ecological characteristics have been proposed as an important factor inreviewing and monitoring the effects of various management measures and it demands differenttools for quantifying and offering a reasonable criterion for comparison of different managements.For this purpose, the Landscape Function Analysis (LFA) method is capable of displaying thestructural and functional status of pastureland with considering the basic and simple indicators andit can be resorted to as a basis for selecting optimal and sustainable management. In this study, itwas found out that among different types of pasture management in Kojour Noshahr including;exclosure, grazing, plowing and planting management - in almost identical conditions regardingplant types, animal types, soil, geology, and climate the exclosure management was significantly(P<0/05) more favorable than other kinds of managements in terms of structural and functionalfeatures and it was followed by planting and grazing. Meanwhile, the plowed pastures weresignificantly unfavorable (P<0/05) both in terms of structural features and functional characteristics.Therefore; exclosure can be a perfect option to protect rangeland resources in this region.
AliB. Mirgalili; MohammadR. Fazelpoor; fariba zakizadeh
Abstract
Grazing animals affect rangeland vegetation structure and function both directly and indirectly.These effects can be assessed in exclosures. In this study, vegetation changes inside and outside ofexclosures of Tanglaybid rangelands, located in south-western part of Yazd province, have beeninvestigated. ...
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Grazing animals affect rangeland vegetation structure and function both directly and indirectly.These effects can be assessed in exclosures. In this study, vegetation changes inside and outside ofexclosures of Tanglaybid rangelands, located in south-western part of Yazd province, have beeninvestigated. Vegetation changes study was carried out in 3 key areas inside and also 3 key areasoutside of exclosure and lasted for 5 years (2000-2005). Every key area included 3 transects of 100meters long and 40 meters intervals. The transects were selected vertical to slope, including 10fixed plots (2×1 m2). Vegetation cover, density and frequency percentage of each plot species weremeasured annually. The random- systematic method was applied as a sampling method. Vegetationchanges inside and outside of exclosure were assessed, in a completely random plan, applyingDuncan's test (P < 0.05). The results showed that vegetation cover percentages increasedsignificantly (P < 0.05), inside the exclosure comparing to outside of it. Mean coverage of annualand perennial grasses and also bushes, inside the exclosure comparing to its outside increased 47,38 and 7%, respectively. Thus, in present research, exclosure has positive effects on vegetationcover changes of several species. Frequency percentage results showed that there was no significantdifference, inside against outside the exclosure in 2000, 2001, 2002, 2003, and 2004. Regardingdensity, there was significant difference only in 2001.The results can be considered in futuremanagement of the area's rangelands and similar regions throughout Iran
yahya Parvizi; mohammad gheitury; Mosieb Heshmati
Abstract
The WEPP physically model is able to dynamically simulate runoff and soil erosion using physical concepts of erosion and hydraulic of overland flow science considering plant growth, residue decomposition, winter process. Determination of the capability of this model in runoff and erosion estimation in ...
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The WEPP physically model is able to dynamically simulate runoff and soil erosion using physical concepts of erosion and hydraulic of overland flow science considering plant growth, residue decomposition, winter process. Determination of the capability of this model in runoff and erosion estimation in different range type with investigation the effects of management were the main objectives of this research. This research was conducted in the Kabode placed across the Gharasoo watershed by installing erosion plot with dimension of 10×3 meter and three replications in three range types at the slopes of 25, 35 and 45%. Climate data including rainfall and air temperature was recorded in the site and additional data including wind velocity and direction, solar radiation and dew point temperature was prepared from Kermanshah synoptic climate station. Event based erosion and runoff was simulated in each plot by the v2008.9 version of the model. Results from model assessment for prediction of runoff indicated that the maximum model accuracy was in 45% slope. Also, mode relative error in runoff in 25 and 35% slope was about 0.61 liter. Overall, model performance in runoff estimation was sought in all three slopes, so that Nash-Sutcliff index was 0.96 to 0.73. Minimum and maximum estimation error in erosion prediction was occurred in 35 and 45% slope, respectively. Model prediction results indicated under-estimation in all the slopes. Negative amounts of Nash-Sutcliff index indicated confirms the low efficiency model especially in conditions prevailing in two slopes of 25 and 35%.
M. Jankju; F. Noedoost
Abstract
Ecological studies on range plants enhance our knowledge on the rangeland ecosystems which are useful for their planning and management. By doing field and laboratory experiments during 2008-2009, ecological conditions were studied in the main habitats of Z. atriplicoides in the rural and winter ...
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Ecological studies on range plants enhance our knowledge on the rangeland ecosystems which are useful for their planning and management. By doing field and laboratory experiments during 2008-2009, ecological conditions were studied in the main habitats of Z. atriplicoides in the rural and winter rangelands of Northern Khorasan province (NKP). Forage quality was also studied at different phonological stages. According to the results, Z. atriplicoides grows in the habitats with mean annual rainfall ranging from 260-380 mm, temperature 8-16 ºC, and altitude 680-1200 meter a.s.l. Topography was as plains and rolling lands, with geologic formations being conglomerate, marl, shale and sandstone. Soil texture was silty loam, weak alkaline, and poor in phosphorus and nitrogen. Vegetative growth and flowering stages were simultaneously occurred at early April till early June, but seed ripening and shedding happened at late June-mid August. Toward the end of growing season, ADF and NDF increased while crude protein decreased, which led to a gradual decrease in forage quality. Ability for growing in different habitats – from cold dry to warm humid- and having protein content and metabolic energy higher than the critical level for rangeland livestock are the relative advantages, whereas significant leaf reduction in response to drought and heat stresses, inability for growing in saline lands and low palatability and preference values are the major disadvantage for Z. atriplicoides in the rangeland of Iran. The most suitable time for livestock grazing and seed collection of Z. atriplicoides in the NKP are May-June and July, respectively.
Pejman Tahmasebi; Ataollah Ebrahimi; Nabiollah Yarali
Abstract
هنگاهی میتوان قضاوت درستی در ارزیابی پوشش گیاهی مرتع داشت که طرح آماربرداری انتخاب شده باشد. از اینرو تعیین یک اندازه و شکل قطعه مناسب که بتواند دقت و صحت مناسبی در ...
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هنگاهی میتوان قضاوت درستی در ارزیابی پوشش گیاهی مرتع داشت که طرح آماربرداری انتخاب شده باشد. از اینرو تعیین یک اندازه و شکل قطعه مناسب که بتواند دقت و صحت مناسبی در برآورد متغیرهای مرتعی پوشش داشته باشد موجب افزایش کارآیی نمونهبرداری میشود. در این مطالعه با لحاظ کردن چندین معیار شامل دقت، زمان، نسبت محیط به مساحت و راحتی و قابل استفاده بودن به دنبال تعیین قطعهی خواهیم بود که برآورد قابل قبولی از چندین متغیر شامل درصد پوشش فرمهای رویشی مختلف، سنگ و سنگریزه، درصد لاشبرگ و خاک لخت داشته باشد. برای این منظور با استقرار قطعههای با اندازه و شکلهای مختلف شامل1×1، 1×2، 4/1×4/1، 4×5/0، 2× 2 و4×4 متری درصد پوشش شکل های مختلف رویشی و زمان نمونهبرداری اندازهگیری در آنها شد. برای انتخاب بهترین قطعه از بین گزینههای فوق از روش تصمیمگیری سلسلهمراتبی استفاده شد. همچنین با استقرار 5 قطعه آشیانهای (تودرتو) با ابعادcm 25*25 متر تاm 16*16 و تعیین قطعههای حداقل، کارآیی این روش با قطعههای فوق که چندین معیار را همزمان در خود لحاظ میکند مورد مقایسه قرارگرفت. نتایج کلی نشان میدهد که دقت برآورد متغیرهای مختلف با افزایش سطح افزایش مییابد. با اینوجود افزایش دقت برآورد متغیرهای مختلف با افزایش سطح در قطعههای کوچکتر بسیار چشمگیر بوده و با رسیدن به قطعه 4 متر مربعی تقریباً به سطح ثابتی رسید. نتایج حاصل از تحلیل سلسله مراتبی نشان داد که با در نظر گرفتن معیارهای دقت، زمان، نسبت محیط به مساحت و راحتی و قابل استفاده بودن، قطعه 4 متر مربعی بهترین گرینه انتخابی برای تخمین متغیرهای پوشش گیاهی است. قطعههای آشیانهای مستقر شده قطعه حداقلی با مساحت بزرگتر از 32 متر مربع را تعیین کردهاند. نتایج حاصل از این پژوهش موید این موضوع است که 1) در مراتع نیمه استپی برای برآورد متغیرهای پوشش گیاهی قطعه 4 متر مربعی بهترین است
2) قطعههای حداقلی که در روش آشیانهای تعیین میشوند نمی تواند در مناطقی که پوشش گیاهی ناهمگنی زیادی دارد بهترین قطعهها برای برآورد چندین متغیر پوشش گیاهی باشد 3) بهترین برآورد از متغیرهای بررسی شده در دو برابر حداکثر تاج پوشش گونههای موجود در منطقه مشاهده نشده است و روش استفاده از دو برابر بودن بودن اندازه قطعه از تاج پوشش حداکثر گونهها برای اندازه قطعه در این مناطق صحیح نیست 4) برای انتخاب بهترین قطعه، محقق باید با لحاظ کردن چندین معیار تصمیمگیری از بین قطعههای مورد نظر، یکی را که بیشترین کارایی را در برآورد متغیرهای پوشش دارد انتخاب کند.
S.M Heshmatol Vaezin; S Ghanbari; ALI Tavili
Volume 63, Issue 2 , September 2010, , Pages 183-14
Abstract
Eremurus and forage are main by-products in the Khazangah rangelands of Makoo region. Eremurus is harvested and used by local people in a period of 30 days during the spring in this region. At this study, Eremurus and forage have been evaluated financially and the data were obtained through field work ...
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Eremurus and forage are main by-products in the Khazangah rangelands of Makoo region. Eremurus is harvested and used by local people in a period of 30 days during the spring in this region. At this study, Eremurus and forage have been evaluated financially and the data were obtained through field work using unstructured interviews as well as direct observation. The harvested Eremurus value was estimated based on harvest costs and by means of market price. The data were analyzed through financial evaluation, annual present net value and infinite present net value or expected value. The results showed that gross revenue, economical rent and economical benefit per household were 4564 and 348 thousand Rials/yr, respectively. The amount of net benefit through harvested Eremurus was also 16748 thousand Rials/ha/yr. The Rangeland Expectation Value per hectare was estimated 670 thousand Rials/yr and 10.5 million Rials/yr from Eremurus and feed, respectively. Total Rangeland Expectation Value per hectare was estimated 11.17 Thousand Rials while the ratio of Rangeland Expectation Value of Eremurus to Total Rangeland Expectation Value was computed 6 percent. The rangelands of this region have much more products. Among them forage and Eremurus have been considered at this study. These products play a main role in local economy of the region.
hassan Miladfar; hossen Barani; ramtin Julaie; parviz Riyazifar
Volume 63, Issue 1 , June 2010, , Pages 105-14
Abstract
The establishment of rational balance between number of users and productivity capacity of rangelands and suitable number of the folk in the ranch units is one of the necessities of the sustainable management of rangelands. Also growth and efficiency of the productive factor would lead to the economical ...
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The establishment of rational balance between number of users and productivity capacity of rangelands and suitable number of the folk in the ranch units is one of the necessities of the sustainable management of rangelands. Also growth and efficiency of the productive factor would lead to the economical benefit maximum .This study was done in order to evaluate the optimal ranch size basis on the social and economical relative sustainability in the rangelands of Urmiya. The statistical information were derived from 203 questionnaire collected from 34 rangeland ranch units in the study area at the year of 2007-2008. Then the costs, incomes and grazing capacity were evaluated in each unit. The suitable number of folk and optimal ranch size were determined based on some criteria such as Total Efficiency Index. Productivity factors and annual costs of family were analyzed using Eviews economic software. The results showed that ranch size per a rancher is not optimal and each productivity unit has used from the rangeland less than optimal limit. At present, utilizable rangeland average per a user is 71 ha. Also the suitable minimum size of folk and rangeland per a family including 5 members is 550 and 350 ha, respectively. So it is able to supply the annual costs of family. Also economically suitable folk number and optimal ranch size were determined 667 and 297 ha, respectively. Therefore we can totally conclude that the folk size of 300 to 350 is a suitable size, either with respect to efficiency of production factors livelihood or preparing of the livelihood per a family unit, which completely depends on the ranching in the region.