فصلنامه تحقیقات مرتع و بیابان ایران
سال بیست و پنجم شماره 4 (پیاپی 73، زمستان 1397)

    This study aimed to determine the best time of seed collection for Artemisia sieberi and Artemisia aucheri in Saleh abad rangelands of Baft County, Kerman province. After selecting a key area, the time of seed collection started from mid-November to end of January for Artemisia aucheri and from mid-October to mid-December for Artemisia sieberi.  The seeds were evaluated for germination traits including germination percentage, germination rate, root length, shoot length, and vigor index. The data were analyzed, and the Duncan test was used to compare the mean values of treatments. The results showed that the delay in the time of seed collection of Artemisia sieberi from mid November to mid December caused an increased germination percentage, germination rate, seed vigor, and seedling length as 115, 119, 222, and 49%, respectively. The seeds of Artemisia aucheri collected in the first half of December compared to the first half of November increased seed vigor index, germination percentage, germination rate, and seedling length as 588, 336, 736, and 61%, respectively.  Our finding showed that the delay in the time of seed collection in both of these species improved seed germination traits and seedling growth.

Over the past decades, due to increased population and consequent increase in the need for food, we have seen extensive changes in land use, and in particular, the increase of agricultural lands. The aim of this study was to evaluate the changes in land use in the Bartash plain in Dehloran city of Ilam province during 26 years from 1988 to 2014 using the object-oriented approach. To accomplish this research, the necessary corrections were made after the acquisition of Landsat TM (1988), ETM + (2001) and Landsat 8 (2014) satellite images, and then, using the object-oriented method, the land use map was prepared for the three time periods. The results of the evaluation of the accuracy of the produced maps show that the highest accuracy and Kappa coefficient with the values of 90 and 95% correspond to the image of 2001, and the lowest them with the value of 80 and 90% was related to the image of 1988. Total accuracy and Kappa coefficient in the image of 2014 with 90% and 92%, respectively show a good accuracy. The results of land use change trend showed that the land use of the fair rangeland had the most changes with a decrease of more than 21 thousand hectares. Agricultural lands are in the next place, showing an increase of over 15,000 hectares (twofold) that could be due to the increase in population and the availability of adequate water resources in this area. The land use of poor rangelands also shows an increasing trend of 1.5 fold, indicating the degradation of fair rangelands. The saline lands initially show an increasing trend but then show a decreasing trend due to converting to agricultural lands. The overall accuracy (900-90) and kappa coefficient (95-90) indicate the high accuracy of this method in determining the land use.

    Determination of rangeland forage quality is an important factor in assessing the nutrition status of livestock dependent on rangeland, determining suitable grazing time, increasing livestock efficacy and less damaging to rangelands. This study was conducted to determine the nutritional value and digestibility of four dominant species of Compositae family in Baft rangelands located in Kerman province. The species including: Artemisia aucheri, Artemisia persica, Scorzonera tortusissimaand Cousina sicigera, which weresampled in phonological stages of vegetative growth, flowering and seeding. The results showed that the mean values of chemical composition of the mentioned species at different growth stages were 9.94, 8.9, 6.21 and 10.40% of crude protein (CP), 45.62, 45.77, 61.07 and 42.83% of NDF and 32.77, 33.05, 46.61 and 31.73% of ADF, respectively. By increasing age of all plant species, CP was decreased (P<0.01) but except for Scorzonera tortusissima, the values of NDF and ADF were increased in other species (P<0.01). The average digestibility of the mentioned species dry matter at vegetative, flowering and seeding stages were 57.41, 53.54, 45.34 and 39.67%, respectively. The average of metabolizable energy (ME) of the mentioned species at vegetative, flowering and seeding stages were estimated to be 2.24, 2.24, 1.86 and 2.26 Cal/g, respectively. The average concentrations of mineral elements such as calcium, sodium, potassium, magnesium, iron and manganese of these four rangeland species were more than the critical requirements of sheep and goat, while the concentrations of phosphorus, copper and zinc in these plants were less than the critical level for sheep and goat requirements. Generally, the four species studied in terms of CP and ME, especially in the early stages of growth, provide the needs of sheep and goats in the region.

The most important executive policy of the government is optimizing range management plans in the rangelands. Improvement, development and proper exploitation of rangelands depend on understanding the current rangeland condition and selecting a range management method (balanced, natural and artificial) to be implemented in the form of a range management plan (RMP). Data were collected from 16 ranch units of Haraz River watershed to investigate differences in methods. At first, the statistics and information of the rangelands including the total percentage of vegetation and each of the important desirable and increasing species, rangeland condition and trend, and rangeland production were extracted and studied in 2016. To determine the best range management method based on rangeland condition, the analysis of variance was used in a completely randomized design with three treatments. To compare the effect of each method during the implementation of the plan and in the current situation on the rangeland condition, trend and production of rangelands, the Duncan's test and to compare the quantitative characteristics measured before and after the implementation of the rangeland management plans, a two-sample independent t-test were used. Moreover, the non-parametric Mann-Whitney U test was used to compare qualitative characteristics using SPSS. In this research, rangeland management methods were considered as a treatment and time intervals were considered as a replicate. The results showed that although the vegetation percentage of palatable species composition did not increase, the balanced and natural methods were the best rangeland management methods in the good and fair rangeland condition, respectively. The reason for not increasing the palatable species was the unsuccessful implementation of planned programs in Range Management Plans (RMPs). On the other hand, although the artificial range management method was correctly performed in the RMPs with poor vegetation types, the implementation of these plans had no significant effect on the rangeland condition and trend of the study rangelands due to the high livestock population. It has also caused the cost of implementing reclamation and improvement projects on the beneficiaries. Although the percentage of vegetation cover of undesirable species of rangelands has increased, over the past 25 years, the total percentage of canopy cover and production has decreased. It seems that rangeland plans will be more effective when there is a balance between grazing capacity and livestock population.

     Use of saline and low yield soils for forage production is an important step towards optimal efficacy of low-quality water and soil resources from agricultural point of view. Atriplexcanescens and Atriplexverrocifera as drought and salinity tolerent species, are able to produce forage in saline and low yield soils. To investigate the possibility of establishing and measuring the amount of forage production in saline and low yield soils, and determining the appropriate planting method, two salinity areas (salinity up to 20 ds / m and salinity up to 40 ds/m) were first selected through soil testing. Then in each region, 45 seedlings of each mentioned species were planted in three replications. The results of the present study showed that the use of Atriplex canescens and Atriplex verrocifera for establishment and forage production is possible in in areas with high salinity (up to 40 ds/m). Analysis of variance of canopy growth and annual production of the mentioned species showed that in saline lands with a maximum of 40 ds/m, the growth rate of the first year of At. verrosifera was more than At. canescens. But in the region with low salinity, At. canescens growth was more than the other species. The production amount of established species shows that the production of At. canescens is more than At.verrusifera. But this difference in salt area is minimized. Therefore, the effect of salinity on the production of At. canescens is tangible and effective. But the production rate of At. verrucifera is more in areas with low salinity. So, this species has more resistance and tolerance.

This paper was carried out to determine the cycle of dust storm in relation with precipitation in 12 months of the year, using processing of digital time series and their correlation with two variables mentioned above. Hence to accomplish the aim of the paper, the frequency of time series for dust storm and rainfall have been analyzed for the long time statistical data collected from 45 synoptic stations(1986-2016), located in the south east of  Iran. In order to understand whether or not any correlation with these two variables, firstly a diagram of the daily changes in dust storm and rainfall cycles was drawn for each month separately. Then, to make sure that the statistics data are normal, the data were analyzed using Kolmogorov-Smirnov test in SPSS software. The results of data normality showed that all statistical data of the parameters used in this research were normal. The results of calculating the correlation coefficients of each month during the course of thirty years, indicated that the correlation of data are significant at (P<0.01 & P<0.05) only in the cold months of the year (January, February, March, April, May, November and December). Also, this study showed that the relationship between the amounts of daily precipitation with an abundance of dust events in the area was negative, and this indicates that the dust could be significantly as reducer or repressive downpours in the region.

Considering the role and importance of grazing on vegetation structural changes, thisstudy aimed to assess the effects of various grazing intensities on vegetation parameters in semi-steppe rangelands of Alavigeh, Isfahan. Three rangeland locations with relatively homogeneous ecological conditions and various long-term grazing intensities (light, moderate and heavy) were selected. Four perpendicular transects with 100 meters length (two parallel transects and tow transects perpendicular to the general slope of the area) were established in each site and vegetation parameters including vegetation cover, density and palatability class of the species were recorded in 10 plots. The Margalef richness index and Shannon-Vainer diversity and evenness indices of the plots were calculated. A one way ANOVA was used to compare the vegetation parameters in sites with various long term grazing intensities. According to the results, the sites with low and moderate grazing intensities had higher plant density and vegetation cover compared with site grazed heavily and these vegetation indices varied significantly between the sites (P< 0.05). The species composition of the light and moderate grazing areas mainly included class II species with 72% and 54%, respectively. The heavily grazed site was dominated by the species with low grazing palatability (69%). The plant diversity, richness and evenness indices of the sites with low and moderate grazing intensities varied significantly (p < 0.05). The log normal was the best fitted parametric model among species abundance models for the low and moderate grazed sites, indicating a stable vegetation community. Log series were fitted to diversity data in the heavy grazed site, indicating an unstable vegetation community. RDA analysis revealed that there was a distinct grazing gradient and three vegetation zones could be clearly separated with various vegetation compositions. Although vegetation condition is appropriate in the sites with low grazing intensity, also the vegetation regeneration can benefit from moderate grazing intensity. Biological considerations are required in the management of rangeland ecosystems in arid and semi-arid ecosystems due to the fragile nature of these ecosystems. 

This study was aimed to investigate the effect of labour division pattern on rangeland management activities in nomadic families as well as women’s role in management of rangelands in two allotments in Shoul Abad region, Aligudarz Township, in Lorestan province. This research was conducted by using survey method. In the first section, some data were collected using irregular interview and observation, and then obtained data was used in a questionnaire design. To determine sample size, Krejcie-Morgan-sample-size-table was used. In quantitative section, a total number of 44 questionnaires with open-ended questions were completed by nomadic women. Rangeland management was studied in three sections of exploitation, conservation, restoration and development. The findings of the present study showed that the effect of labor division pattern on the activities of these families is such that women play their most roles in rangeland exploitation and have a smaller role in the conservation and restoration of rangelands. The results also showed that nomadic women as in the past have played a significant role in the production of livestock and dairy products as well as harvesting of medicinal and edible plants, and they have an important role in the production and supply of these products.

Bamu National Park, has witnessed an annual fire and its repetition for many years. Considering the importance of preserving the park and its proximity to Shiraz refinery, fire hazard zoning was conducted using geographical information system (GIS) and Analytic hierarchy process (AHP). With regards to the four factors of physiography (elevation, slope, direction), climate (temperature and precipitation), human factors (tourism, industrial areas, military regions, residential areas and roads) and fuels (vegetation type and density) and weighting according to digital layers, expert opinions, questionnaire filling and integration of manufacturing layers, the final mapping of fire zoning classified into 0-20 (no risk), 20-40 (low risk), 40-60 (medium risk), 60-80 (risky) and 80-100 (high risk). The results showed that 23.3% (14263 hectares) and 20.25% (2.84) of the area were located in the dangerous and very dangerous zones, respectively. Evaluating the provided model accuracy showed that 76.60% of the previously fired areas located in dangerous and very dangerous zones, and this subject shows the adaptation of the reality with the prepared maps. With a logical connection between the risk areas and the real places, the success of this method can be proved. So, it is suggested to develop a particular crisis management plan and increase the equipments and human resources for preventing fire and its spread in dangerous and very dangerous zones.

     Festuca sulcata L. as a perennial grass is special to semi- steppe rangelands in alpine regions. In order to evaluate the growth quality, forage and seed yields, five extensions of this species were planted under rainfed conditions in a completely randomized block design with three replications at Samian station in Ardebil. After establishment of the seedlings, traits, such as viability percentage, crown cover, shrub height, seedling vigor, and forage and seed yields were measured from 2010 to 2014, at the end of the growing season. The data were analyzed using SAS software and comparison of the means of the evaluated traits was performed by Duncan's multiple range tests at P ≤ 0.05. The results showed that the greatest percentages of crown cover (997.77 cm2), shrub height (45.88 cm) and seed viability (100%) were belonged to Sarein-Alvaris accession. Average values of forage and seed yields were 528.58 and 93.33 kg ha-1 y-1, respectively. There was no significant difference between accessions in term of seed yield but there was a significant difference (P ≤ 0.01) between years. The average seed production in the studied ecotypes was 95.33 kg ha-1. Consequently, superior accessions of this species with great potential for foliage production can be used in the process of restoration and development of semi- steppe rangelands in alpine region.

Traditional animal husbandry has the highest share in the exploitation of the country rangelands. Although more than half of the forage required for livestock is supplied from sources other than grazing in rangelands, most pastoralists believe that traditional livestock husbandry is not economically justified in Iran. Therefore, the current study is a step towards economic analysis of animal husbandry activity, which is dependent on the forage of summer rangelands of Sajjadroodwatershed in Babol during a season of the year. Data related to economic analysis was completed based on a survey method and a questionnaire. The statistical population consisted of three allotments with range management plans and three allotments without any range plans. Using the Cochran formula, 82 ranchers were selected as needed samples for this research. In this study, the net profits of ranchers from livestock activities and other socio-economic factors affecting ranchers' income were investigated. The results showed that the profit/cost ratio of traditional husbandry activity was 1.41 and had economic justification. However, there were no significant differences between the profitability of the rangelands with and without plans and between the ranchers with small, medium and large numbers of livestock. In 2016, average net profits per head of each livestock in rangelands with and without plans were 29477.63 and 22130 Rials, respectively that were not statistically significant. According to the results, it was suggested that the best way to improve pastoralists' economic power was providing subsidized forage, low-interest banking facilities, changing in livestock breeding, and establishing pastoral cooperative companies.

Unfortunately, due to the improper use of natural resources, tremendous changes on the Earth happened which are harmful to human beings. The multidimensional nature of sustainable development has caused to pay more attention to the use of compatible, resistant, productive, high quality and palatable species. One of these species is Astragalus curvirostris as a permanent species, which one of its habitats is in Beluman rangelands with an average height of 1960 meters above sea level and an average annual rainfall of 593.3 mm. In two times and two methods of planting, split plots were arranged in a randomized complete block design with three replications during four years (from 2013 to 2016). The main plot included two treatments of planting season consisted of autumn and spring, and the subplots included two methods of seed cultivation and seeding. Analysis of variance was used to compare significant differences between treatments, and distribution of mean treatments was analyzed by Duncan test. The results showed that there was a significant difference between the average number of available plant stands in different treatments including autumn seed sowing, autumn seed spreading, spring seed sowing and spring seed spreading at 1% level (P≤0.01). It means that its cultivation type and season have different performance on plant coverage. In addition, there was a significant difference between the plots at 1% level, which in fact can depend on the implementation of the treatments in each plot. Finally, it was found that Astragalus curvirostris achieved the best level of success in autumn and the seed sowing method.

In this study, the dust phenomenon was studied at the station of Isfahan temporally and spatially. For this purpose, the data, the time and date of the observation, the direction and wind speed, and the current weather condition were prepared. After extraction of dust codes (06 and 07) and statistical analysis of the data related to this phenomenon, the annual and seasonal wind rose and storm rose of the station were mapped using WRplot & WDconvert software during the statistical period of 2013-2002. The results showed that there were 525 days of dust in the region, which was the most frequent in 2012 with 62 days. Also, in May and spring, the highest frequency of dust occurred. The study of wind rose and storm rose annually confirms the formation of wind tunnel on the western-eastern route. The annual dust rose, divided into two meteorological codes 06 and 07, indicates that winds with dust from the Midwest are involved in the transport of suspended particles and formation of local dusts. Seasonal storm rose show the impact of different atmospheric systems throughout the year on the formation of dust phenomena in the region better and more accurately. With the onset of the cold season, the winds with dust are increasing from the northern half to Isfahan and reach the maximum in the winter, but with the start of the hot season, and especially the summer season, it is more intense than east to Isfahan, and from the west almost reaches zero.

The destructive phenomenon of desertification is one of the serious ecological crises in the present day. To improve the efficiency of combating desertification projects and inhibit natural resources destruction, it is necessary to establish a comprehensive and systematic assessment method that uses a variety of criteria and indicators to achieve actual results. Land degradation assessment strategies are generally based on expert opinions and usually evaluation models based on multi-criteria decision-making models are not very noticeable in Iran. In this study, fuzzy logic approach as one of the effective ways to assess some important criteria in the field of destruction and desertification was used. For this purpose, after the preparation of units, field samples were taken in each unit and then, using groundbreaking and kriging methods, the initial continuous lattice maps in the GIS environment were prepared. In the next step, the layers were assigned to the fuzzy layers using the linear functions. Finally, with the use of fuzzy operators and gamma operators, the final map of desertification severity was presented on a scale of zero to one. In order to facilitate better understanding of the results, the final map was classified into four classes of very low to very high severity. The obtained results show that approximately 40% of the studied area is in high severity and 17% is in very high severity. It should be noted that the above classification can be reconsidered in various managerial scenarios.

      Plant species have different ecotypes. Identification of ecotypes with more yield operation can be useful and commercially profitable. This is the first study to investigate resin yield amount of Ferula pseudalliacea and edaphic conditions of its habitats in desert rangelands of Yazd province. For this purpose, in each region, 20 plants of the same age (5-6 years) were completely randomly selected and used according to the conventional method. Soil sampling was carried out at a depth of 0-30 cm. All data were analyzed using SPSS16 and Excel software. The results showed that bitter asafetida plants had significantly more resin yield in 7, 8, 11 (P<0.05), 9 and 10 cutting times (P<0.01) but less yield in 3 and 13 times in Chenarnaz habitat (P<0.05). The total amount of resin with 63.63 g showed a significant increase in Chenarnaz compared to Borooieh region (60.14) (P<0.01). The most amount of resin yield was observed in 9 and 10 incisions in both habitats. Totally, it is recommended to harvest bitter asafetida during ten cutting times in Yazd province rangelands for sustainable exploitation. Comparison of soil parameters showed that the sand percentage in Borooieh region and the percentages of moisture, silt, organic matter, nitrogen, phosphorus and potassium in Chenarnaz region were significantly higher (P<0.01). Increasing soil moisture storage, organic matter and essential elements of the plant caused resin yield improvement of asafetida in Chenarnaz region. In this study, acidity had a significant increase in Chenarnaz habitat, which is an effective factor in the growth and production rate of asafetida. Chenarnaz region had numerically more lime and better operation of resin yield. According to the results, bitter asafetida plants of Chenarnaz region had better resin yield operation.

Rules and regulations in the last few decades have had a great impact on rangelands and its exploitation; on the other hand, these rules are the foundation of the policies governing the type of management and relevant government agencies. The aim of this research was to examine the effectiveness of the laws and regulations related to the rangeland and range management, with the help of a survey of experts and rangeland specialist. In this regard, the community of rangeland specialists or natural resources experts, who were empirically and professionally related to rangeland and range management issues, was identified and their opinion was collected through questionnaires. The audience was divided into three main groups of executive and research experts and academics. A total of 268 questionnaires were completed and the responses were analyzed using descriptive statistical methods. The results showed that, in general, the existing rules and regulations could not prevent the degradation of rangelands and result in rangeland conservation and improvement, and these rules have greatly contributed to the collapse of the range management systems in the past, while an appropriate management system has not been replaced. Moreover, a large part of respondents believed that the laws and regulations need to be reviewed and updated.

The main objective of this research was to evaluate vegetation changes and soil indicators in the Kalat Sadat Sabzevar area under rangeland management practices. Vegetation factors including plant species production, vegetation cover, cover percentage, litter percentage, plant species density, and rangeland condition and trend were measured at the exclosure site and adjacent control site. The assessment was conducted using a random-systematic method with a sufficient number of samples and appropriate distribution of samples at the time of rangeland readiness. The rangeland trend was determined on the basis of two methods, and rangeland condition was determined based on the four-factor method. Soil sampling was carried out at a depth of 20 cm. A total of 12 soil samples were taken from the first, second and third transects (exclosure site), as well as fourth, fifth and sixth (control site). Data were analyzed by the independent t-test using SPSS software. According to the obtained results, the highest canopy cover percentage in terms of palatability belonged to class II plants (19.37), and in terms of vegetative form belonged to the perennial plants (16.2). Also, the largest share of production in the exclosure site and grazing site was related to shrubs and perennial grasses, respectively. The results showed that clay, silt, lime, organic carbon, nitrogen and electrical conductivity were significantly different at 5% level between the exclosure and grazing sites, but there was no significant difference between acidity and phosphorous. Therefore, exclosure could be recommended as an improvement practice to be carried out in more areas of the region.

Precipitation temporal trend analysis and study of the drought condition have been of great concern during the past century because of the attention given to global climate change by the scientific community. The aim of present study was to investigate and analyze the rainfall trends and its affected drought conditions in Jazmurian basin using non-parametric mann-kendall method and multidimensional comparison of drought indices including Standardized Precipitation (SPI), deciles (DI), the percentage of normal (PNI), Chinese Z (CZI) and the Z score (ZSI) with rainfall data from 24 gauged stations for the period of 1983 to 2013. For this, the drought indices were calculated, and then categorization was performed on the basis of similarity and correlation using cluster analysis method. The results proved a positive and significant increase in the rainfall amount of 1992-1993 and 1995-1996 years. Statistical analysis showed that the highest amount of rainfall occurred in the years of 1992-93, 1995-96 and 2004-2005 and the lowest in the years of 1983, 2000, 2003 and 2005 in the basin. Cluster analysis showed that the ZSI and PN indices with similarity of hundred percent in the diagnosis of wet and dry periods, intensity, duration and continuity were completely similar and had the highest similarity among all the groups. The CZI and SPI with 99.5 percent similarity were in the second level of similarity as well. Validation of the results through the numerical comparison of SPI and CZI indicates the same trend of two indicators and little differences in presenting the drought conditions of Jazmorian basin. However, in assessing the severity of droughts, CZI showed more severe drought condition. Overall, the results showed a greater focus of the drought in the southern east and southern parts of the basin indicating the high probability of drought occurrence potential of the basin. Therefore, the study of drought through CZI and SPI indices in the basin of Jazmorian is suggested for the proper policy making and management of water resources regarding conservation and increasing of the productivity from environmental, economic and social point of views.

Knowing medicinal plants, measuring structural features and their species diversity indices are of the essential requirements to determine the suitability of rangelands for the use of medicinal plants. In this regard, the research was carried out in the mountain rangelands of Anbaran. For this purpose, vegetation cover was measured using 320 plots of one square meter, with a distance of 10 meters from each other along 100-meter transects in 16 vegetation types, and the values of species diversity indices in different elevation classes and aspects were calculated. Based on the results, 16 medicinal species are distributed in the plant composition, with a relative importance varying from 0.9 to 59. The highest relative importance is related to Verbascum erianthum, Cynodon dactylon and Acroptilon repens, and the least belongs to Papaver acrochaetum, Hyoscyamus arachnoideus, Iris falcifolia, Allium scabriscapum and Matricaria chamomilla.The results showed that the values of the Shannon–Winear  in the altitudes of 1750-1500 meters and 1750-200 meters were 0.569 and 0.651, respectively, showing no significant difference with each other. The value of the index in the northern and southern directions is equal to 0.691 and 0.511, and the northern aspects are more favorable than the southern ones. Therefore, with regard to the range of Shannon–Winear index (0-4.5), it seems that the rangelands are not desirable for the species diversity of medicinal plants, which is necessary to increase species diversity with direct management. The findings of this study can be used to locate medicinal plants in order to protect, exploit, seed production and provide part of the livestock holder’s income.