IRANIAN JOURNAL OF RANGE AND DESERT RESEARCH
Year:2020 | Volume:27 | Issue:1 (78)|Papers Count:15

Rangeland capacity depends on forage produced in the rangeland, allowable use of plant species, forage quality, and degree of rangeland health. Range species have a certain production in different months and years. It is not possible to plan and manage rangeland and livestock without knowing the production characteristics and forage consumption of rangeland during the grazing period. This study was conducted in 2008-2010 years, and the forage production and utilization rate was measured in different months and years. The annual precipitation were 138, 200, and 330 millimeters for three years, respectively. The results showed that total forage production was significantly different between years (p<0. 01). Forage production was 485. 7, 1372, and 1844. 4 Kg per hectare, respectively. Also, there was a significant difference between (March to August), with 94. 7% of range production in the first two months (March and April), and 5. 3 % of remaining forage production was in the last four months of the vegetative period. Therefore, forage production during the growing season is not suitable. Other results showed that the amount of utilization in three years was 400, 751, and 490 kg / ha, respectively. Although the difference was not statistically significant, in the dry year 2008, 83 percent and in the wet year 2010, 26. 6 percent of forage production was consumed. Thus, in the dry year, as forage production declined, livestock utilization increased by 83%, which is not commensurate with range capacity. Other results showed that the share of annual and perennial plants in total range production was 81% and 19%, respectively, and the share of livestock diet was 90% and 10%, respectively. Therefore, in order to achieve sustainable production, proper management of rangeland and the use of native species such as Onosma bulbotrichum, Ankyropetalum gypsophiloides, Convolvulus reticulatus and Salvia compressa are recommended.

Determining the capacity of grazing is one of the most important issues in rangeland management and failure to comply is one of the causes of rangeland degradation. The purpose of this study was to determine the grazing capacity in the middle Taleghan rangelands in the form of short-term policy to consider the factors that should be applied in calculating the grazing capacity and in addition to protection, can help improve the rangeland condition. Sampling was carried out in June 2013 by the random-systematic method and the amount of forage production in each vegetation type was harvested separately from livestock grazing species in all three classes of palatability I, II, III. After that, the allowable use was determined, and then the short-term grazing capacity was determined by the method of calculating the daily energy required for livestock and according to the forage quality. The results showed that the grazing capacity in the area varied from 0 to 1534 for the Fashandi race adult sheep in the grazing season (four months). The area required for a Fashandi race sheep grazing varied from 1. 92 to 8. 63 hectares during the grazing season. In general, based on the results, the grazing capacity of all studied rangelands during the grazing season (four months) was equivalent to 6802 Fashandi race adult sheep. However, the grazing capacity of studied rangeland with the good condition was about 145 Fashandi race sheep per hectare and about 19 livestock per hectare for rangelands with poor condition. Therefore, in calculating the capacity of grazing, it is necessary to pay attention to the palatability, allowable use, forage quality, and the difference in the livestock daily requirement depending on the weight of grazing livestock in rangelands and its mobility.

The rainfall storage along with the cultivation of plant species is important in the restoration and improvement of rangeland, especially in arid rangelands. In this study, the effect of rainfall storage treatments including contour furrow, pitting, and crescent pond was investigated on the establishment of Ferula tabasensis in Kalmand Bahadoran of Yazd province. Seeds were planted at two seasons, early fall as fall sowing and late winter as spring sowing. The research was a split-plot design based on randomized complete blocks with three replications. The main plot was planting time (spring and fall) and the subplot was planting method (furrow, pitting, and crescent pond). The seeds were planted in 2013 and 2014. The results showed that the seed emergence rate in fall was significantly higher than that of spring planting. Among the planting methods, the impact of the crescent pond method was slightly more than the other two methods. In general, planting methods caused more than 50% seed emergence. Although some of these seedlings were destroyed in the years after planting for various reasons, the presence of about 30% of seedlings in the second and third years of planting indicates the relative success of rainfall storage methods in the establishment of cultivated plants.

In order to effective management of animal species, it is necessary to identify habitats with high desirability for the target species, so that by preserving those habitats and planning for their proper management, the target population will be protected. This study was conducted to determine the relationship between rangeland species and the suitability of Iranian deer habitat in different seasons based on dung groups in Kalmand plain of Yazd province. For this purpose, sampling was performed using random permanent plots with 200 meters long and two meters wide and with two replications during five field investigation in summer and autumn. Based on the number of plots with dung control or randomized plots were established in the whole habitat and in different directions and investigated every 45 days. Finally, all the required maps and information integration were prepared and performed in Arc GIS 9. 3 software. The results showed that there was no significant difference between the two seasons in terms of the dung group’ s density in plant communities. In terms of cover percentage, Artemisia and Astragalus sp. had a significant increase in presence points compared to random points. Onopordon sp. canopy cover in absent points and Acanthophyllum sp. in random points were higher as compared with presence points (p<0. 01). According to the map, for deer in terms of suitability, 23% and 47% of the area was located in the first-class and second-class, respectively. According to the results of this study, among the habitat variables, species richness, cover percentage of Artemisia, and distance from the road were the most influential variables in the choice of deer habitat.

Plant litter is one of the best factors in the protection and stability of soil and by decomposition of litters, the percentage of organic matter could be increased, which also improves the chemical properties of soil and plant production. The aim of this study was to compare the litter quality accumulated beneath three shrub species (Amygdalus scoparia, Ebenus stelata, Daphne mezerum) by measuring the soil chemical (carbon, calcium, magnesium, nitrogen, phosphorus, and potassium) and physical (Electrical conductivity and acidity) properties in Marvast rangelands, Yazd province, Iran. At the end of the growing season, after preliminary investigations, the habitat was identified and fifteen sites were selected and soil samples containing litter material were randomly taken beneath and outside of the shrub canopy covers. Then, the chemical characteristics of litter were measured in the laboratory. In order to compare the litter characteristics, a one-way ANOVA was made between species and, between outside and beneath the shrubs. Mean comparisons were made using Duncan’ s method. The results showed that the litter samples under E. stelata and D. mezerum shrubs had the highest values for calcium, magnesium, and nitrogen contents. Also, the litter samples collected from outside shrubs had the highest values of electrical conductivity as compare to beneath three shrub species. The phosphorus content between the species and between under and outside the canopy was statistically equal. Generally, the results of this study showed that the woody species in arid regions had different capacity in litter quality and soil improvement, which should be considered in rangeland improvement and development activities.

In the last four decades, land use changes in Iran as a human factor of desertification has occurred with increasing speed and has led to the intensification of land degradation in various land uses. In this study, due to the wide range of these changes, remote sensing technology was used to assess land use and vegetation changes in Damghan plain. The area of the study region was classified into three classes including bare land, lands with vegetation cover (agriculture and rangeland), and urban areas and changes of the land uses were compared over four periods. The results indicated an increase trend of 184% and 1. 07% in urban and bare land use, respectively, and reduction in agriculture and rangeland use was 15. 7%. Using the Normalized Difference Vegetation Index (NDVI), the results of classification of vegetation in the region were such that class 1 (index less than zero), increased from 93. 2 to 99. 5 percent, class two ( (0 to 0. 2), decreased from 5. 6 to 0. 38 percent, class three (index between 0. 2 to 0. 5), from 1. 1 to 0. 01 percent, and class four (index between 0. 5 to 1) from 0. 03% to 0, which indicates the correctness of the results of the survey of land use changes, and both confirm the increase in bare lands and the reduction of vegetation cover. Also by using the Iranian model's climatic indices, the results of the 17-year calculations during the period of 1997 to 2013 indicated that desertification had a decreasing trend in three classes: weak, severe, and very severe, and an increasing trend in the middle class. Finally, by combining the findings of the Iranian model and the results of remote sensing method, a weak trend in desertification based on climate criteria in the region was confirmed.

The time of preparation seeds and storage methods has a great impact on the seedling viability and establishment. The effects of seed harvesting time and storage methods were investigated on seed germination of Krashninkovia ceratoides in the Shahrak-Imam Seed Production Station in Neyshabur Iran. Experiment treatments were: the effect of appropriate seed harvesting time on irrigated and rainfed cultivation, two methods of seed storage in normal temperature, and cold storage, and seed scarification (dormancy breaking) on seed germination percentage. For each experiment, 25 seeds were located in a germinator in four replicates with 14: 10 hours of light and dark periods. The results showed that the storage conditions had no effect on seed germination percentage for up to six months; however, with the continuation of seed storage under normal conditions, after 271 days, the germination percentage reached zero. The highest germination percentage (more than 80%) was observed in September, and there was no significant difference between irrigated and rainfed seedlings; however, in November harvest, the average germination of seedlings, which were planted by rainfed method, was higher. Scarification and removing the seed coat significantly reduced germination percentage. Based on the findings of this study, it is suggested that the seeds of this plant be collected in November. Eurotia seeds do not require coat removing or storage in refrigerator, and are able to retain germination for up to six months in a natural environment.

The aim of this study was to investigate the combined effect of fire and grazing on the characteristics of plant diversity indices in the semi-steppe rangelands of Chaharmahal and Bakhtiari province. Therefore, 16 sites were selected with different periods of fire and grazing intensity, and 18 quadrats along transects at each site were determined and then a systematicrandom sampling method was performed. Then, species diversity and Beta diversity indices were calculated. To determine the effects of fire, grazing, year, and their interactions on the diversity indices, the General Linear Model (GML), and to determine the significant effect between the fire site and control (no fire) site the method of T-Test were used. The results showed that in areas with moderate grazing intensity with different periods of fire, Simpson, Shannon, and richness diveristy indices increased compared to control areas. However, the beta diversity decreased. In areas with high grazing and different periods of fire, Simpson and Shannon diversity indices increased compared to control, and in areas with 1-3 and 3-5 years fire, species richness increased and decreased, respectively. Also, in different periods of fire, the beta diversity decreased compared to control. Despite the revival of some plant species in fireaffected areas over the time, their percentage significantly decreased under grazing intensities compared to control, and the highest percentage of perennial grass cover in different periods of fire was observed in medium garzing areas. After a fire in a semi-steppe rangeland, proper management of the rangeland can increase the quality of usable forage and provide species richness.

Identification of the effective environmental factors in establishing native vegetation of each region can help in the proper management of rangelands. A suitable habitat will have a significant impact on the survival and reproduction of species. With the advancement of statistics and the geographic information system, it has become possible to determine the habitat of plant species using modeling methods. Therefore, the present study was conducted with the aim of preparing a prediction map of Artemisia aucheri habitat using factor analysis of ecological niche in the summer rangeland of Baladeh Noor region of Mazandaran province. To achieve this goal, a map of environmental variables including (physiography, soil and climate), after sampling of soil profiles and also collecting information about climatic variables from Meteorological Organization of Mazandaran province and physiographic maps using geographic information system techniques GIS in cell size 10× 10 meters was prepared. Also, 30 sites were recorded as species presence sites by classified random sampling method. Factor analysis of ecological niche is one of the profile models and uses species presence data to provide a habitat prediction map. Based on the results, the variables of average annual rainfall, geographic direction, electrical conductivity, and neutralized soil materials were used as influential environmental variables. Also, the evaluation of the model using the Boyce index showed the high and good accuracy of the ecological niche factor analysis for Artemisia aucheri species in the study area. In addition, the results of this study showed that the Artemisia aucheri species has relatively limited ecological niche and has a tendency to live in its own habitat conditions.

Invasive species are the major threats to natural ecosystems worldwide. Pteridium aquilinum is one of the most widespread invasive plants among pteridophyta in the world. We studied the effect of Pteridium aquilinum invasion on species composition, richness, diversity, and forage production in some of the summer rangelands of Bandapi Babol in Mazandaran province, Iran. Sampling of vegetation was performed in four invaded vegetation types (including Fagus orientalist forest, Crataegus shrubland, Crataegus+Berberis shrubland, and invaved rangeland) and control rangeland, in which P. aquilinum was not present. In one-square-meter plots, the canopy cover percentage was estimated. Twenty-five m square plots were used for shrub species. The cover percentage of density and average height of P. aquilinum, were also measured. The palatable forage was also cut in the plots, and samples were dried in air and then weighted. The results showed that plant composition in P. aquilinum was different from the surrounding rangelands. Twenty-five plant species grew only under P. aquilinum stratum, while 11 plant species were limited to rangelands outside of the P. aquilinum population. These changes have a significant correlation with the canopy cover percentage, density and height of P. aquilinum. Annual plants in P. aquilinum population showed a significant decrease. Except for the Crataegus+Berberis shrub type, no significant change in forage production was observed in other plant species with P. aquilinum invasion. The spread of this plant in the rangelands lead to reduce the presence of high quality rangeland grasses, increased species richness, and finally cause to reduce in plant diversity. If the P. aquilinum plant is controlled in this area, the vegetation composition under stratum is not enough for regeneration and it is necessary to use the seeds of high quality rangeland and native plants of the region in a suitable way.

The aim of this study was to investigate the best planting time and method of A. podolobus. The experiment was conducted as a split plot design based on a completely randomized block design with three replications at Hana Semirom station, Isfahan Agricultural and Natural Resources Research Center during 2013 to 2015. Main factor was sowing date (fall and spring) and sub plot was sowing method (linear seeding and crescent shaped bounds). The results showed a significant effect of planting time, planting method, and its interactions on the percentage of establishment. The percentage of establishment of fall cultivation was 14. 28% and spring planting was 27. 78%. The lowest percentage of establishment was observed with 6. 35% in sowing method and the highest with 35. 71% in crescent banquet method. The interaction of this trait showed that the lowest percentage of establishment was observed in spring cultivation treatment and seeding method (4. 76%) and the highest percentage was observed in crescent and spring cultivation methods (47. 61%). The results indicated that crescent-shaped bounds were more appropriate in both spring and fall cultivation. Forage yield was strongly affected by the planting season and in fall and spring cultivation and were 7 and 15. 6 grams per plant, respectively. Forage yield was 9. 5 g in seeding method and 13. 16 g in crescent bounds. The range of changes in this trait ranged from 6 g in fall cultivation and seeding method to 18. 33 g per plant in spring cultivation and crescent bounds method. In general, the results showed that for planting this species in semi-steppe areas, spring planting in the form of crescent bounds and non-coating seeds is suitable for maximum establishment.

In order to achieve a suitable cultivation method and season of Sanguisorba minor in rangelands, the present study was carried out during 2013-2016 in Homand Absard research station. The design was conducted in the form of split plots based on the randomized complete block design with three replications. Factor A was cultivation time (in two levels of fall and spring rangeland) in the main plots and factor B was cultivation method (in two levels of seeding and seeding combined with rainfall storage using crescent bounds) were located in the sub-plots. The percentage of plant establishment was recorded at the end of the growing season in each year. Analysis of variance was performed using SPSS 22 software and the means were compared by Duncan method. The results showed that season and cultivation method had a significant effect on species establishment. Fall cultivation was better than spring and sowing with rainfall storage was better than regular sowing. Last year's results showed that the highest percentage of establishment was related to fall cultivation with rainfall storage with 45% establishment that the seedlings reached flowers and seeds.

The most important structural factor that contributes to desertification is the appearance of salt domes. Due to its solubility and also the effect it can have on the quality of water and soil resources in the surrounding areas, its study is of special importance in agricultural projects and natural resources because it will reduce soil fertility and expand deserts. In this study, it has been tried to determine the quality of surface and groundwater and also to study the factors of geology, morphology, salt dynamics, and tectonic fractures around the Dashti salt dome and its relationship in desertification. The thickness of the salt column in the Dashti salt dome has been estimated at approximately 2, 800 meters, and salt glaciers are affected by the topography of the dome (northeastern-southwest) from both sides and laid on the surrounding rocks. For this reason, low sediment is constantly threatened with contamination. Examining the dynamics of the dome, it was found that the balance between the amount of supply and the lack of salt in the desired salt dome is always established and plays an active and permanent role in the expansion of the desert around it. The flow of groundwater in the aquifers of the region is mainly controlled by the permeability of tectonic joints and faults around the dome and confirms the effect of the dome on the salinity of groundwater. Close activity to the surface of the Dashti salt diapir before the orogeny of Zagros is an important and fundamental factor in the destruction of the Kangan anticline soils and the expansion of desertification.

Due to the limitations of field measurements of vegetation, the application of plant indexes to estimate rangeland biomass using satellite data can be very useful in rangeland studies. For this purpose, it is necessary to identify appropriate vegetation indices. The aim of this study is to investigate the possibility of estimating rangeland biomass using plant indices obtained from digital data of Landsat 8 satellite and determining the most appropriate ones in semi-arid regions of the northeast of the country. For this purpose, the average values of plant indices NDVI, TDVI, SAVI, ARVI, EVI, OSAVI, IPVI, GRVI, and GNDVI within each unit of one hectare of the studied basin network were calculated. Then, the correlation of these values with the average measured field values of these units was examined by linear regression, and the regression model of each index was determined to estimate biomass. Finally, the results were validated and a field biomass map was prepared for each index. The results showed that all indexes had a high and acceptable correlation with real biomass data. Based on the validation results, the SAVI plant index with a coefficient 0. 79 and root-mean-square error of 14. 73% was the most suitable plant index for estimating biomass in the region. By using the wavelengths located in the blue band, these indicators modify the effect of dust in the calculations, which reduces the atmospheric effect and improves the results of calculating the NDVI index, and it can be called the modified NDVI index. According to the results, plant indices obtained from the ratio of near and visible infrared bands are highly correlated with biomass. In general, the shorter the wavelengths used by plant indices, the lower the accuracy of estimates in arid and semi-arid regions.

In the last three decades, in order to better understand and protect the services of ecosystems, an attempt has been made to consider the economic value of their services in the form of virtual markets. Therefore, the authors of the present study, considering the valuable services of Sheikh Musa rangeland ecosystem in Babol district, using conditional valuation method and twodimensional dual technique and distribution of 157 questionnaires from 2017-2018 among the studied community (eastern banpey part of Babol city) to investigate the factors affecting the amount of interest paid by stakeholders in the form of protective valuation. Michelle and Carson were also used to select the sample. The present research method is quantitative and to analyze the results, Shazam11, maple18 and Excel2016 software packages were used. The validity and reliability of the results of the Logit model showed that the proposed price variables, age, lack of household supervision, visit to the region and environmental ethics were effective factors in the willingness to pay people to protect Sheikh Musa's rangeland ecosystem. Also, the amount of willingness to the annual payment of people equal to 78792. 92 Rials ($ 1. 87) and the total protection value of the ecosystem were 2776 million Rials ($ 66096). Also, the minimum voluntary investment (available fund) to maintain the rangelands ecosystem of Sheikh Musa in terms of the preferences of stakeholders of the target community was estimated at 1289 million Rials. The value obtained shows that the protection of Sheikh Musa's rangeland ecosystem is very important due to its valuable services by stakeholders. As a result, it is suggested that the formation of NGOs and workshops in the city by relevant organizations, ethics, and environmental trends change people to protect the desired ecosystem. Also, in order to better understand managers and people about rangeland ecosystems, it is recommended to conduct several studies on other functions and services of these types of ecosystems.