Journal of Rangeland Science
Volume:2 Issue: 4, Summer 2012

Studies on vegetation changes of rangelands under grazed and non-grazed conditions are of great importance in the range management planning programs. To determine the change process of vegetation, this study was performed in Inche Shorezar site of Golestan province for nine years (1997-2005). The vegetation parameters were measured every year in several fixed plots inside and adjacent of exclosures. The canopy cover of each species was estimated in each plot. Forage production was randomly measured on one meter square plots in each year using the clipping and weighing method. Correlations between canopy cover of species and growth forms with the rainfall of different months and periods were calculated using SPSS software. Results showed that total canopy cover in 2005 was significantly higher than 1997 both inside and adjacent of exclosures which has been mainly related to increased annual plant cover but the perennial canopy cover was decreased in these years. Perennial species of (class I) did not grow inside the fixed plots. Cover of increasers (class II) species was reduced from the first year to the final one for both inside and adjacent of exclosures. However, the cover of (class III) species in the final year was not significantly increased than that for the first year. Forage production generally was higher inside than adjacent of exclosures. Litter increased during the study period for both inside and adjacent. Litter was significantly higher inside of exclosures than adjacent in 2005. Although the plant canopy cover was affected by rainfall but correlation coefficient was statistically significant only for total, annual and some perennial canopy cover species. Although total and annual cover was high inside and adjacent of exclosures in 2005, the cover of perennials was decreased. By the reduction of palatable species, unpalatable species were increased inside and adjacent. Although by increasing the plant cover, the range condition was relatively improved, this improvement was achieved by the increase in the annuals instead of perennials. It was concluded that the exclosure cannot be used as a range improvement method to improve these rangelands’ conditions. For the rehabilitation of these areas, human interference is necessary.

The effects of Range Management Plans (RMP) on soil and vegetation characteristics were studied in Eshtehard rangelands at Alborz province. The parameters of yield, canopy cover, range condition and trend, bulk density, Organic Matter (OM%), Nitrogen (N), Phosphorous (P) and Potassium (K) were estimated on soil samples in sites of Ghenzel Cheshmeh as RMP and sanctum of Rahmanyeh village. The data were analyzed using T- test. The results showed that due to the reduction of plant species in the arid and semi-arid areas and the need for vegetation change for long time, the difference of canopy percentage between two sites were not significant but implementation of rangeland management plan increased the yield and improved range condition and trend. RMP had increased the N and OM% of the soils and decreased P, K and bulk density.

Determination of forage quality of available species is one of the fundamental factors for the management of rangelands. Near-Infrared Reflectance Spectroscopy (NIRS) was used to analysis the Nitrogen (N), Acid Detergent Fiber (ADF), Dry Matter Digestibility (DMD) and Metabolizable Energy (ME) content of three phenological stages (vegetative, flowering and seeding) of Bromus tomentellus samples in grazing pastures of Iran. The sample set consisted of 40 samples for calibration and 23 samples for validation was used to prediction N, ADF, DMD and ME, separately. The samples were measured by reflectance NIR in a 950-1650 nm range. Calibration models between chemical data and NIR spectra were produced using the method of Partial Least Squares (PLS). The coefficients of determination (R2) and standard error of cross validation (SECV) were 0.94 (SECV: 0.208%), 0.98 (SECV: 1.76%), 0.98 (SECV: 1.97%), and 0.97 (SECV: 0.34%) for N, ADF, DMD and ME, respectively. The results obtained from this study indicated that NIRS had a potentiality to be used in predict the N, ADF, and the estimated DMD and ME of forage samples content.

One of the ordinary methods to protect, rehabilitate, and enhance an ecosystem function in arid and semi-arid areas of the world is sand dune stabilization using biological practices. Plantation of species on the soil plays a great role in sustainable management of the ecosystem. This research studies the effects of cultivation of Haloxylon ammodendronand Atriplex canescens on physical-chemical characteristics of soil. The study area was Yousef Abad, Neyshabour, located in the northeastern part of Iran in which these two plants species were cultivated 20 years ago. The study area was then compared with a control area near the investigated area. Two different sites within the cultivated area as well as a site in control area were selected for soil sampling. Six samples were taken at each site from depths of 0-20 cm and 20-80 cm, in the sites of H. ammodendron and A. canescens three profiles were randomly digging from under the shrubs canopy and 3 of them were sampled from between the shrubs totaled 36 soil samples. The percentage of clay, silt, sand, electrical conductivity, soil acidity, organic matter content, nitrogen, phosphorus, potassium, calcium, sodium, and calcium carbonate of each sample were measured. The collected data were analyzed and means comparisons were made using LSD by SAS software. The results showed that the three sites had different soil characteristics. H. ammodendron led to increasing soil nutrient factors and soil fertility after 20 years of cultivation but silt particles transportation and wind erosion was reduced in site of A. canescens in this period.

There are some barriers for rangers to take part in range plan projects and evaluation. Their participation is very useful for range managers to plan and provide solutions for solving problems. This study aims at comparing barriers of participating from rangers and experts point of view in Lar moor rangelands, Tehran, Iran. In this research, data were collected based on documentation-library and field working. The statistical populations of the study were 410 rangers and 43 experts that arranged based on Cochran formula, 178 rangers and 35 experts had answered the distributed questionnaires. Validity and reliability of questionnaires were assessed by a preliminary test using SPSS software and Cronbach alpha coefficient. The results of Mann-Whitney U test showed that the opinions of two groups on both the effects of legislative initiatives, economic, social-cultural and educational barriers and non-participating rangers in the range projects of Lar moor are the same. But comparing the experts and rangers` opinions on the effects of management factors on non-participating rangers showed that the experst`s view of on the effects of this factor are more agreeable than those of rangers. Also, the results of this test showed that participation rate of rangers in range projects is the same in terms of both ranger and expert groups. Prioritizong results showed that from the viewpoint of rangers, economic, legal, educational, social and cultural barriers have contributed to non-participation of rangers in the range projects. But from the viewpoints of experts, legal, educational, administrative, socio-cultural and economic barriers are the reasons of rangers’ non-participation.

Information on different rangeland plants’ nutritive values during various phonological stages is of importance for the rangelands management. This information helps rangeland managers to choose proper grazing times to achieve higher animal performance with no detrimental effects on the rangeland vegetations. Effects of various plant parts’ phenological stages and vegetation types on reserve carbohydrates and forage quality indicators were investigated during 2009 and 2010 in Sabzkooh rangelands at Charmahal province, Iran. Plant samples were collected based on a Completely Randomized Design (CRD) at 3 phonological stages (seedling, vegetative and flowering) with 5 replications. The species included grasses (Secale montanum and Festuca ovina), forbs (Lotus corniculatus and Sanguisorba minor) and shrubs (Kochia prosterata and Salsola rigida). Aerial plant parts’ samples were harvested and oven-dried at 80oC for 24 hours; then, they were analyzed for determining the amounts of Water Soluble Carbohydrates (WSC), Crude Protein (CP), Acid Detergent Fiber (ADF), Dry Matter Digestibility (DMD) and Metabolic Energy (ME). Results showed that forbs contained more WSC as compared to the other two vegetation types (grasses and shrubs). For other forage quality traits (CP, DMD, and ME), there were significant differences between species over two years and higher and lower forage qualities were obtained for forbs and shrub, respectively. For WSC, Sanguisorba minor and Lotus corniculatus had the highest values while Secale montanum and Salsola rigida had the lowest WSC content.

Ecotones are zones of gradual changes from an ecological system to another. Ecotones monitoring could be important to find out the reason for changes and limits. In this research satellite data were used to analyze the ecotone boundary in Fars steppic rangelands using IRS LISS III and Pan data of year 2006. The real vegetation map and ecotones prepared through Geo-eye images from Google earth software and calibrated using field study. Five soil line vegetation indices such as SAVI, MSAVI2, TSAVI, OSAVI and GESAVI from processed data were calculated. Each of these indices was classified by applying density slicing analysis method. Then the accuracy of produced maps was audited with error matrix method. The results show OSAVI and SAVI had the highest overall accuracy and kappa coefficient as 82.1% and 82% for overall accuracy and 76% for Kappa coefficient, respectively. According to this research, soil line vegetation indices have intermediate accuracy for separation of arid rangelands ecotones in Iran with IRS data, although, OSAVI and SAVI perform better than the others.

Groundwater is among the most important resources of drinking water supply of the worldwide population. Use of recharge area is one of the methods for artificially recharging groundwater. Selection of suitable sites for artificial recharge is very important and must be carried out accurately. There are different types of land use, only rangelands are appropriate for artificial recharge because of their topographical situations. In this study, the groundwater artificial recharge suitable area of Silakhor, Borujerd of Iran rangelands was investigated and extracted using Geographic Information System (GIS) and Analytic Hierarchy Process (AHP) method. The layer information of rainfall, soil, lithology, slope, land use and fault components were prepared and weighed by applying AHP method and were used for artificial recharge site selection. Aquifer artificial recharge maps showed that in Silakhor catchment 14%, 64.8% and 21.2% of the area of the catchment had high, moderate and low capability for artificial recharge, respectively. The most suitable areas were located in the low land areas.

Recognition of habitats and conditions of species presences in different situations can be effective in proper utilization of vegetation. Little is known about the vegetation composition of Boralan Mountain region located in North West of Iran in the border of Turkey and Azerbaijan with the altitude range of 800-2000m. The aim of this study therefore was to investigate the floristic composition quantitatively and analyze the vegetation response to altitudinal gradient conditions of mountain. Firstly, plants were collected by floristic field survey and identified using the floras. To investigate the relationship between the gradients of elevation and vegetation, two transects of 100m were established at every 100m of elevation belts and the percentages of canopy cover and density of species were totally recorded in 20 plot samples using a random plot design. Plant community zones were characterized on the basis of species’ cover dominances using cluster analyses. According to this study, the area includes 108 species that were classified into 26 families. Totally, Poeaseae and Asteraceae with 40 percent cover dominance were more frequent than other families. Based on species similarity of elevation classes, the cluster analysis led to four vegetation type groups. The grass group and the shrub group occurred on high altitudes at 1900 m and lowland sites at 800-1300 m, respectively. The results also showed that elevation variations had considerable effects on diversity and richness indices of vegetation groups with the highest number of species at high altitudinal belt. It seems that precipitation improvement and low grazing intensities has mainly caused these changes.

The main objective of an ecosystem sustainable management is to preserve its capacity to respond and adapt to current disturbances and/or future changes, and maintain the provision of environmental goods and services. Two very important properties linked to this objective are the ecosystem resilience and resistance to disturbance factors. The objective of this paper is to recommend conceptual modifications to the integration of key ecological concepts such as dynamic equilibrium, resistance and resilience to the ‘State and Transition Model’ (STM) in order to apply them in a more feasible way for rangeland management. Ecological resilience describes the amount of change or disruption required to transform a system from being maintained by one set of mutually reinforcing processes and structures to a different set of processes and structures. STMs integrated to concepts of structure, function and energy provides greater opportunities to incorporate adaptive management, more accurate forecasts and a better and easier comparison between rangeland ecosystem types than traditional STMs. We propose to enhance the STM considering four principal axes (ecosystem functions and/or processes, natural disturbances and/or negative management activities, required energy to return to the previous state, and structural ecosystem changes and transition time) also simultaneously, to compare the “robust” ecosystem to “fragile” ecosystem. The recommended modifications enable STMs to identify a broader range of variables to anticipate and identify conditions which determine state resilience to better inform ecosystem managers of risk and restoration options.