JOURNAL OF RANGELAND SCIENCE
Year:2017 | Volume:7 | Issue:3|Papers Count:12

Introduction: Scientists call pasture a natural ecosystem and range is an agricultural ecosystem.In this point of view although pasture that was full of plants growing by itself and not growing by human being (Pirdashti, 2007; Mohgadam, 2005) and two groups of living beings such as human being, plants, domesticated, and not living being like weather, Wind, gradient which are effective in making of pasture.....

Evaluating rangelands means to identify and create potential and actual rangelands in order to utilize this valuable natural resource properly. Hence, one of the important factors in rangeland management is to determine range suitability and recognize factors affecting it. Weighted Linear Combination Method (WLC) is one of the most common methods used for locating and Analytic Hierarchy Process (AHP) method is one of the most used methods of criteria prioritization and weighting. The purpose of this study was to evaluate range suitability of Bagheran Birjand watershed area in Southern Khorasan Province, Iran using AHP-Fuzzy method in a region with an area of 11879 ha in 2014. For this propose, in the environment of Geographical Information System (GIS), the maps of factors affecting the suitability (slope, production, erosion, quality of water resources, water need estimation percent and distance from water sources) were prepared. Data were standardized using fuzzy method and for weighting the criteria, the Analytic Hierarchy Process method was used. The results of AHP-Fuzzy model based on the weighted linear combination showed that 55.43% of rangelands were in suitability class of moderate suitability (S2), 9.55% of the lands were in suitability class of low suitability (S3) and 6.21% of the lands were in non-suitability (N) class. So, the limiting factors in this model for sheep grazing in the study area are water resources, high slope and vegetation.

One of the most important issues in structure-function relationship modeling is that each rangeland has numerous functions and each of them can provide the most benefits in a certain state of that ecosystem. In fact, relationship between structure and function can be varied in different states. After presentation of the Linear Structure-Function Model based on the Clementsian succession theory, another conceptual model was proposed to modify it based on more realistic State and Transition theory. While previous models mostly suppose one single function in their simulations, in this article, we suggest a conceptual model that summarizes the relationships between Ecosystem Structure and Multiple Functions (ESMF) in various states. The model can be useful for rangeland managers to get a rather correct understanding about multiple functions in rangelands. By this right understanding, the rangeland managers will be able to identify the best states for their ecosystems and try to reach to these states which can provide totally maximum benefits. This model shows that some functions in rangelands may conflict with or overlapped each other and some functions may not show a meaningful relationship with structure in ecosystems so that it is a very important task for managers to choose the states with the highest benefits and less conflict.

The main objective of this study was to assess factors affecting early entrance and later exit of herders from summer rangelands. The study population consisted of heads of Nomads in Kouhdasht region, Lorestan province, Iran. According to Cochran formula among 1038 Nomadic families, 310 families were selected with stratified random sampling in 2015. In order to assess validity, expert's opinions were considered and face to face interviews and questionnaires were applied to collect data, andCronbach’s Alpha was used to assess reliability. To determine the factors influencing movement calendar, the factor analysis (principle component analyses) and KMO statistics were used. The variables were ordinated by factor analysis into six factors. Results of Mann-Whitney test indicate that annual herd calving and distance of winter and summer rangelands had a significant effect on livestock entrance and exit date to the summer rangeland. Results of Kruskal-Wallis test showed that herders who had private rangeland and those who had cooperative rangelands leave summer rangelands later and in the right time, respectively. Herders whose main job was ranching had good knowledge about livestock entrance and exit date of rangeland.Results obtained from factor analysis showed that factors of tribes’ tendency to use fresh fodder for their livestock, lack of forage in the winter rangelands and increased annoying insects were effective in early migration of nomadic. The livestock weight loss and lack of places in the winter rangelands were effective in early and late exit of livestock from the summer rangeland.

Cocksfoot (Dactylis glomerata L.) is an important cool season grass species in the moderate climate of Iran. In order to evaluate the yield and quality traits, an experiment was conducted in irrigation conditions using 36 accessions ofDactylis glomerata using a randomized complete block design with three replications in Islamabad, Kermanshah province, Iran in 2010. Characters such as forage dry matter (DM) yield and quality traits were measured. There were significant differences between genotypes for yield and all of quality traits. Results of correlations between traits showed that Crude protein (CP) was positively correlated with total ash and negatively correlated with both water soluble carbohydrates (WSC) and the crude fiber (CF). There were strong negative correlations between digestibility dry matter (DDM) and both acid detergent fiber (ADF). Using Cluster analysis (Ward method), the accessions were classified into five groups. Factor analysis after Varimax rotation revealed that three factors explained 83.63% of total variance. The first and the second factors were related to the forage quality. The third factor was correlated with DM yield. Based on factor analysis and means comparisons, it was concluded that the accessions Karaj197, Zanjan499 and Ghazvin783 were more efficient for both forage yield and quality traits than other accessions of theD. glomerata.However, accession Karaj10112, Russia1551, USA1715 had higher values of the quality traits but lower production. In spite of high forage yield, accessions Marand 255, and Karaj 10113 had a poor quality. Therefore, the accessions with higher forge yield and quality indices were introduced for improving the synthetic varieties.

Turfgrass is one of the important components of ornamental plant in the construction of parks and landscapes so that the purpose of this study was to investigate the influence of type and different concentrations of Copper, Zinc and Cobalt on germination and seedling growth of perennial ryegrass(Lolium perenne L.) and red fescue (Festuca rubraL.) seeds in in vitro conditions. This study was carried out in 2014. A factorial experiment was conducted based on a completely randomized design with three replications in laboratory. Seeds were sown in the sterilized medium containing 7 g/L of agar under the laminar air flow. Then, three solutions of ZnSO4, CuSO4 and COCl2 in five concentrations of 0, 20, 50, 100 and 200 mg/L were prepared. Seeds were placed in the incubator at 24oC and 50% humidity for 25 days. Seed germination traits and seedling growth were recorded. Results showed that zinc and copper had minimum and maximum inhibitory effects on seedling growth, respectively. At the presence of copper, by increasing the concentration from 0 to 200 mg/L, the germination and seeding growth were sharply reduced. Inhibitory effects on seedling growth were found in higher concentrations than 50 mg/L at the presence of zinc and cobalt metals. The minimum rate of germination and seedling growth in both red fescue and perennial ryegrass was observed in the concentrations of 20 to 200 mg/L of copper. Therefore, perennial ryegrass and red fescue as turfgrass cannot germinate and grow in soils with copper contamination even at low concentrations, but they can tolerate moderate concentration zinc and particularly cobalt contamination in the polluted environments.

Classification of Ecological Species Groups (ESG) in plant community analysis is one method to describe vegetation and relating them to environmental factors. This study was conducted to recognize ESG and their relationships with some environmental factors in Chamanbid-Jozak protected area from 2014 to 2016. This area is located in the eastern part of North Khorasan province, Iran. The study area contains steppe vegetation with some woodlands and shrubs ofPaliurus spina–christi, Cerasus pseudoprostrata, and Cerasus microcarpa. To recognize ESG, a systematic-random sampling, by using 1 m2 Sampling Unit (SU), was carried out to provide a matrix of 74 sampling units and 42 species. Canopy cover percentage of different species was recorded in each SU.Physiographical, physical, and chemical factors, including altitude, slope, soil texture, gravel percentages, Organic Carbon (OC), Nitrogen (N), Potassium (K), lime, soil acidity (pH), Phosphorus (P), and Electrical Conductivity (EC) were measured. Euclidean distance and Ward's method of clustering were used to classify the plant species. Six ESG were detected in clustering and indicator species analyses. The relationships among these ESG and environmental factors were analyzed using Canonical Correspondence Analysis (CCA). The first ESG consisting four indicator species was influenced by organic carbon and K of almost f.0 fertile soils. ESG2 and ESG3 consisting four and one, indicator species, respectively. These ESG were only slightly affected by phosphorus and less by environmental factors evaluated in this study. ESG4, including eight indicator species was mostly affected by environmental factors such as altitude, slope, pH, and N. Both ESG5 and ESG6 were affected by gravel percentages. ESG classification of vegetation for sound and proper resource management in future via using long-term projects is recommended.

Description of vegetation patterns associated with environmental factors such as grazing, climate, landforms, substrate variables etc. are helpful for land management planning. This study used new synecological tools to investigate plants composition and to provide ecological descriptions of plants communities of communal pastures in Sahelian Ecological Zone of Niger. Vegetation and several environmental variables were recorded in 197 plots using the Braun-Blanquet cover-abundance scale. A composite soil sample of about 1 kg from each plot was collected for analysis. A total of 252 species were recorded, belonging to 148 genera from 47 families, in which the angiosperms families counting 251 species are more represented and the pteridophytes are represented by one species belonging to the family of Marsileaceae. Poaceae, Leguminosae-Papilionoideae, Convolvulaceae, Cyperaceae and Leguminosae-Mimosoideae are the largest families. High abundance of the Poaceae species reveal the great potential forage value of the Sahelian rangelands. Most of the plants species are Therophytes and widely distributed elements in the tropics, revealing therefore an arid environment with great potential forage value under high disturbance, accordingly poorly managed. Arid ecosystems under heavy disturbance are susceptible to desertification. Nine pasture vegetation communities have been discriminated, distributing along the environmental gradient. Significant abiotic factors of plants distribution and their assemblage to form communities are geomorphology, total alkalinity, magnesium, phosphorous total and the cationic exchange capacity. Significant factors as well as sand, clay, silt, calcium, organic carbon, available phosphorous contents and plants composition varied differently with the definite plants communities. Plants communities under depression have great amounts of moisture and soil factors of soil fertility, therefore more resilient. Likely, plants communities located on sandy plains and dunes slopes or summits are more vulnerable to desertification than those located in fertile depression with great water contents.

Structure, Conduct and Performance (SCP) is used as an analytical framework, to make relations amongst market structure, market conduct and market performance The objective of this study was to analyze the factors, which affect SCP of livestock markets in the Butana area, Sudan in 2011. A total sample of 222 livestock traders were surveyed using structured questionnaire in seven primary and secondary markets distributed in Butana area. Both descriptive statistics and econometric methods were used to analyze data collected from traders using SPSS19 and STATA10 software. The logit regression model was employed to estimate the variables affecting the SCP of livestock markets in the area under study. Poor infrastructure of livestock markets, prices of livestock and high transaction cost had negative and significant effect (P<0.0) on structure, conduct and performance (SCP) of primary markets. As expected, lack of access to credit had negative effects (P<0.05) on SCP. Policies are required to improve livestock markets facilities, to encourage a higher price for the sale of animals at a younger age and to provide credit services to livestock traders in order to develop the sector and improve the livelihoods of pastoralists in the Butana area.

Negative impacts of gully erosion in marly areas are severe due to improper landuse practices such as irrigation, tillage, overgrazing and degradation of vegetation cover. The objective of this research was to evaluate gully thresholds related to plant vegetation cover and landuse change in the Agriculture (AG), Fair Rangeland (FR) and Weak Rangeland (WR) areas of Ghaasr-e-Shirin, Kermanshah, Iran in 2015. The topographical parameters and vegetation cover were measured in the field. Furthermore, nine flumes were performed to determine the critical values of hydraulic parameter and sedimentation. Results revealed that cross-section, width, depth and gully branches length in the FR were significantly lower than those for AG and WR (p<0.05) affected by plant canopy and litter. The significant differences were found between three sits for soil organic carbon (SOC), electrical conductivity (EC) and hydraulic characteristics (inlet discharge, velocity, loaded sediment). Higher vegetation cover in the FR was attributed to the increased hydraulic thresholds and adversely limited cross-section enlargement. Finally, the sediment concentrations in AG, FR and WR were 15163, 9560 and 12000 ppm, respectively. Lower SOC was found in WR and AG due to higher concentration of load sediment. Hence, it was concluded that bare soil, poor vegetation and lower SOC are considerable reduction factors in gully thresholds and subsequently, off-site sedimentation and SOC loss in the study area.