Journal of Rangeland Science
Volume:7 Issue: 1, Winter 2017

Preference value means livestock preference to eat some plants relative to other plants or species. Accordingly, by studying the preference values, the range managers could determine the rangelands grazing capacity to achieve the optimum performance of livestock and to guarantee the stability of rangeland ecosystem. The objective of this study was to determine the preference value of perennial grasses using two methods of preference index (species feeding frequency) and sheep grazing time (feeding time recording) in a semi-steppe rangeland in the middle Alborz Mountains of Iran during four consecutive years (2010-2013). The collected data were tested for normality and then, analyzed by the software of SAS9.1. The means comparisons were made using the Duncan method. Results showed that sheep preferred five grass species (Bromus tomentellus, Festuca ovina, Dactylis glomerata, Agropyron intermedium, and Agropyron trichophorum) in the rangeland. There were significant differences between species and years for grazing time method; however, there were no significant differences for preference index. Also, there were significant differences between months within years for both methods. Results showed that A. trichophorum with the average value of 13.8% grazing time was ranked as the first species followed by D. glomerata with the average value of 11.1% as the second one (Grazing time method). There were no significant differences between A. trichophorum, B. tomentellus, D. glomerata and F. ovina regarding the preference index with the average values of 0.57, 0.75, 0.70 and 0.56, respectively. Overall, the results indicated that grazing time percent method in semiarid rangelands gives more realistic results as compared to the preference index method because of the concrete and tangible results.

Rangeland management plan is one of the major means of management and utilization of rangelands in Iran. The formulation of these plans for the rangeland users should be studied from the ecological and socio-economic points of view. One of the main envisaged activities in almost all the management plans is the grazing system. An experiment was used to study the effects of three deferred grazing systems (15, 30, 45 days delay) and control treatment (Non- grazed) on vegetation parameters in semi-arid rangelands of Jashlubar in Semnan province. The experiment was conducted using a completely randomized block design (RCBD) with three replications over 6 years (2006-2011). In each experimental unit, data from three life forms of vegetation (shrub, forbs and grasses) were collected along a 30 m transect within ten fixed quadrates (0.5 × 0.6 m2) appropriate to vegetation sizes. In addition, forage productions of two life forms (forbs and grasses) were collected over 5 years. Data were analyzed using SAS software and means comparison was made based on Duncan’s method. The results showed the significant effects of deferred grazing systems on the growth of shrubs in terms of canopy cover. However, there were no significant differences between treatments for canopy cover percent of forbs and grasses. The lowest shrub canopy cover was obtained in 45-day delay of grazing. There were also significant effects of deferred grazing systems (15, 30 and 45 days delay) on forage production of both forbs and grasses (P

Exclusion and not using of rangeland in the long term affects the composition and homogeneity of vegetation and consequently leads to the improvement of plants status. In this study, the characteristics and structural changes of the rangeland of Gonbad, Hamadan province, Iran, in 2014 (after 20 years of enclosure) were evaluated using Braun-Blanquet plot, Phytosociology and multivariate analysis by the software PC-Ord5. According to clustering diagram and Indicator Species Analysis, it was found that the studied region had 10 vegetation types and 17 Indicator Species. Detrended Correspondence Analysis (DCA) showed that in the first axis the variables: stone and gravel percentage, Electrical Conductivity (EC), clay, and organic carbon were important and in the second axis canopy cover of grasses, total canopy cover, and pH were important. Principal Component Analysis (PCA) confirmed the relationship between plant communities and environmental factors in the enclosure region. It was found that there are correlations between the echo logical units and the factors: stone and gravel (0.25), clay (-0.26), sand (0.28), silt (0.38), slope (-0.36), total neutralizing value (0.34), and plant species indicators that resulted to the separation of the units. The results showed that in the long-term enclosure, plant communities tend towards a uniform and homogeneous composition and consequently led to the improvement of the rangeland vegetation conditions. Therefore the density, composition and the class I plant species have increased.

Insurance services and financial compensation are regarded for the consequences of events that may happen or not.Farmers and stakeholders can be benefited from the agricultural and natural resources insurance so that they can attain much more stability in resources management, especially through mitigating the effects of potential and imminent risks. The current research was aimed to determine the effective factors in the acceptance of livestock and rangeland insurance by stakeholders in Agh Ghala, Golestan Province, Iran in 2015. Data were collected based on the survey-descriptive research method. Statistical population was all the rangers having a range management plan. Among 93 subjects, sample size was determined as 76 people based on Cochran formula. The effective socio-economic variables among stakeholders were determined using logistic regression. Results of logistic regression suggest that such variables as livestock insurance against previous 20-year risk factors, risk taking and insurance expert knowledge had positively significant effects and family size had negatively significant effects on the acceptance of livestock and rangeland insurance (P≤0.05). Variable of "insurance expert knowledge" had the highest impact on adopting livestock and rangeland insurance among the factors entered into logistic regression model (P≤0.05). It was concluded that holding the extension workshop on risk transfer and dealing with different aspects of insurance provided by an educator who is fluent in native language will be effective.

The extinction of some of medical plants is not only due to the overuse of them and the grazing pressure but also their incorrect exploitation methods. Ferula assafoetida is one of the most important medical plants in Iranian rangelands, which is gradually disappeared from its habitats due to destructive traditional exploitations. Therefore, in order to determine how different incision techniques (exploitation methods) affect F. assafoetida properties, a study was carried out in the research field of Agricultural and Natural Resources Research Center in Mashad, Iran from 2009 to 2010. F. assafoetida plants were five years olds. The plants were cultivated in four densities in the field (25×50, 40×50, 55×50, and 70×50 cm) and four incision treatments as horizontal cutting (traditional), 45-degree cutting, concave cutting and non-incision (control) using a split plot design based on the completely randomized block design with three replications. In each plot, three plants were selected and leaf area, number of leaves, basal diameter, dry matter of post-harvest leaves and survival rate were measured. Analysis of variance of data was conducted and means comparisons were made using Duncan methods. The results showed the significant effects of incision on all the F. assafoetida traits (P

Rangeland degradation is one of the global concerns affecting the pastoralists and those who suffer from its negative environmental consequences. Grazing exclosure has been extensively used among the techniques implemented by the government to protect the fertility of threatened rangelands. The impact of exclosure has been a controversial issue; therefore, it is important to understand its effectiveness in restoring the degraded rangeland ecosystems. The goal of the present study was to evaluate the changes in some physico-chemical properties of soils following the grazing exclusion as compared to the adjacent grazed areas in three winter rangelands in Golestan province, Iran in 2011-2012. In each rangeland, ten soil samples were taken at the depth of 0–20 cm. Then in the laboratory, some soil properties such as soil texture, bulk density, porosity, saturated humidity, pH, EC, OM, total N, lime content, the amount of exchangeable Na, K, Mg and Ca were measured. Data of exclusion and grazed areas were analyzed using the independent T test in SPSS18 software. The results demonstrated that the establishment of exclosure had positive significant effects on the soil physico-chemical properties in Gomishan and Inchehbroun rangelands. So, a significant increase in the mean value of porosity, saturated humidity, OM and total nitrogen (p