Azad Kakehmami; Ardavan Ghorbani; Mehdi Moameri; Sahar Ghafari
Volume 28, Issue 3 , October 2021, , Pages 537-550
Abstract
By evaluating land use change and land cover, it is possible to plan and land manage to reduce the impact of alteration and degradation of exploitations. The purpose of this study was to evaluate land use changes in Ardabil province between 1987 and 2015 using Thematic Mapper (TM) sensor of Landsat 5 ...
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By evaluating land use change and land cover, it is possible to plan and land manage to reduce the impact of alteration and degradation of exploitations. The purpose of this study was to evaluate land use changes in Ardabil province between 1987 and 2015 using Thematic Mapper (TM) sensor of Landsat 5 and Operational Land Imager (OLI) sensor of Landsat 8 satellite images. Firstly, the efficiency of the object-based classification method was evaluated using ground control points, error matrix, and comparing total accuracy and kappa coefficients for the resulting maps. Total accuracy and Kappa coefficients for 1987 were 82.3% and 0.70, and 2015 were 94% and 0.90, respectively. Change detection results showed that from 1987 to 2015, rangelands decreased by 4.2%, equivalent to 75039.3 hectares and forests decreased by 0.5%, equivalent to 9393.7 hectares compared to the total province area and irrigation farming increased by 3.1%, equivalent to 55276.8 hectares, residential areas increased by 0.8%, equivalent to 14989.7 hectares and dry farming increased by 0.7%, equivalent to 12632.4 hectares compared to the total province area. The most significant changes that occurred from 1987 to 2015 were the conversion of rangelands to dry farming with 13.8%, equivalent to 141794.2 hectares and irrigation farming lands with 4.8%, equivalent to 49836.9 hectares of rangelands, irrigation farming to dry farming with 7.7%, equivalent to 11464.8 hectares and forests to rangelands with 6.1%, equivalent to 1059.9 hectares which indicate that the requirement of a serious revision of the management policies.
Ardavan Ghorbani; Ardashir Pournemati; Nazila Bibak
Volume 26, Issue 1 , June 2019, , Pages 1-17
Abstract
The aim of this study was to assess the rangeland health of North Sabalan in three-elevation classes (less than 1500, 1500 to 2100, and 2100 to 2700 meters), which were the representative of rural, rural-nomad, and nomad rangelands, using the landscape function analysis (LFA) in Ardabil ...
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The aim of this study was to assess the rangeland health of North Sabalan in three-elevation classes (less than 1500, 1500 to 2100, and 2100 to 2700 meters), which were the representative of rural, rural-nomad, and nomad rangelands, using the landscape function analysis (LFA) in Ardabil province. For sampling, three 50-meter transects were established in each elevation class according to the uniformity of the habitat and distribution of patches. Using the LFA framework, three characteristics including stability, infiltration and nutrient cycling of soil surface were determined using 11 indicators. Statistical analysis of data was conducted using the LFA method and instructions of Tongway and Hindley in Excel software. The soil stability index for vegetation life forms in the elevation class of 2100 to 2700 m was more than that of the other two elevation classes, with significant difference (P>0.05); however, there was no significant difference between the first and the second class .Comparison of the infiltration and nutrient cycling indices for vegetation life forms in the elevation class of 2100 to 2700 m was also more than those of the other two elevation classes with significant differences (P<0.05). The stability index in the third elevation class (72.35) and in the second class (48.75), the infiltration index in the third elevation class (73.31) and in the first elevation class (15.99), and the nutrient cycling index in the third elevation class (78.75) and in the first elevation class (10.12) had the highest and least values, respectively. Overall, the health condition of the third elevation class was better than the other two classes. By examining the functional characteristics of ecological patches, we can identify the vegetation indicators affecting rangeland health, and then conduct proper management to protect that ecosystem.
Jaber Sharifi; Morteza Akbarzadeh
Volume 26, Issue 1 , June 2019, , Pages 40-48
Abstract
Knowing the ecological characteristics of plants and consequently changes in forage production during the season of grazing for grazing management is essential. Therefore, understanding the annual and monthly production of different rangeland types is essential for efficient ...
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Knowing the ecological characteristics of plants and consequently changes in forage production during the season of grazing for grazing management is essential. Therefore, understanding the annual and monthly production of different rangeland types is essential for efficient and effective forage management. Consequently, relationships between forage production and climatic variables should be considered. For this purpose, the annual forage production was measured in the research exclosure of Arshaq Site rangelands in Ardabil province during 2007-2010 by clipping and weighing method. The monthly rainfall in this period was calculated using Mashkin-Shahr synoptic station data and then the amount of cumulative rainfall in winter and spring of each year was calculated. Afterward, the relationship between production and winter and spring rainfall as well as rainfall of different months of winter and spring was studied separately. Statistical analysis was performed using SAS software. According to the results, the average forage production during four years was calculated of which 28.95% belonged to Artemisia fragrans, 26.35% to Kochia prostrate, 19.55% to Stipa hohenackeriana, 4.77% to Astragalus brachyodonuts and 20.38% to the other species. Analysis of variance showed that the production of species among years were significant (P<0.01). In terms of stability (interactions of year × month), Artemisia fragrans and Kochia prostrata were stable, with a high yield; however, Astragalus brachyodonuts and Stipa hohenackeriana were stable with a low yield.
Farid Dadjou; Ardavan Ghorbani; Mehdi Moameri; Mahmoud Bidarlord
Volume 25, Issue 3 , November 2018, , Pages 577-593
Abstract
The purpose of this study was to investigate the relationship between rangeland aboveground production based on total aboveground production and life forms of grasses, forbs, and shrubs with 25-year temperature and precipitation data, the year before sampling, and the year of sampling in Hir and Neur ...
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The purpose of this study was to investigate the relationship between rangeland aboveground production based on total aboveground production and life forms of grasses, forbs, and shrubs with 25-year temperature and precipitation data, the year before sampling, and the year of sampling in Hir and Neur rangelands in Ardabil province. To determine the aboveground production, the amount of production was estimated using the harvesting method in one square meter plots (totally 330 plots) in three elevation classes under the range of 1446-2750 meters. Temperature and precipitation were calculated for each plot. Aboveground production maps were prepared in a GIS environment using extracted regression equations. The results showed that over the years, precipitation decreased and temperature increased, and aboveground production also decreased in relation to those climatic factors. Moreover, there is a significant relationship (P<0.01) between the aboveground production of life forms and total aboveground production with climatic factors, and aboveground production of grasses and total have a direct relationship with precipitation; however the maximum aboveground production of forbs was recorded in the middle ranges and maximum aboveground production of shrubs was recorded in the higher ranges of annual precipitation. Grasses and total aboveground production had an inverse relationship with temperature, and the maximum aboveground production of forbs and shrubs was recorded in the middle and lower ranges of annual temperatures, respectively. According to the accuracy of derived regression equations, the maps prepared by climatic data of 1394 and 1395 were better than 25-year climate data. The results of this study can be used for the supply-demand balance of aboveground production, biomass accounts, and ecosystem carbon balance indicator that is potentially an important tool for sustainable development.
Amir Mirzaie Moousavand; Ardavan Ghorbani; Mohammad Ali Zare Chahooki; Farshad Keivan B ehjoo; kiomars Sefidi
Volume 25, Issue 2 , August 2018, , Pages 235-247
Abstract
The aim of this study was to investigate the effect of environmental factors on Prangos ferulacea Lindl. and P. pabularia Lindl. distribution in the rangelands of Ardabil province. Seven habitats of Prangos genus were identified, so that P. ferulacea was distributed in three ...
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The aim of this study was to investigate the effect of environmental factors on Prangos ferulacea Lindl. and P. pabularia Lindl. distribution in the rangelands of Ardabil province. Seven habitats of Prangos genus were identified, so that P. ferulacea was distributed in three habitats and P. papularia in two habitats. In each habitat, sampling sites were identified and in each site three transects of 100m were established, and the density of the study species were recorded in ten plots of 4m2. Soil samples were taken from the depth of 0 to 30 cm at the start, middle and end of each transect. In the vicinity of each habitat, sampling was done in the same way. In sampling plots, elevation, slope, aspect, and soil characteristics such as organic matter, N, P, K, pH, EC, and texture were measured. To investigate the effects of environmental factors on the presence or absence of the study species and to compare the characteristics of the variables measured one-way ANOVA and Tukey test were used.Discriminant analysis was used to determine the degree of importance of the environmental variables measured in the distribution of the study species. Results showed that P. pabularia was distributed in the habitats with the high content of P, clay, EC, rainfall, sand, slope and pH; while P. ferulacea was distributed where the elevation was high but rainfall and the content of K were low. According to the results of discriminant analysis, variables such as EC, organic matter, K, elevation, slope, aspect, silt, clay, rainfall, and temperature were effective in discrimination of sites and species distribution. The results of the present study could be useful to propose the species for range management, improvement and reclamation.
Jaber Sharifi; Amrali Shahmoradi; Allahvirdi Noori; Farzaneh Azimi Motam
Volume 24, Issue 4 , January 2018, , Pages 719-729
Abstract
The major portion of our rangelands are located in arid and semi-arid regions. In this climate, variability of vegetation under climate change impact of balanced energy flow in ecosystems ranges vegetation is that the generally composition and structure of vegetation typically occurs over time. on the ...
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The major portion of our rangelands are located in arid and semi-arid regions. In this climate, variability of vegetation under climate change impact of balanced energy flow in ecosystems ranges vegetation is that the generally composition and structure of vegetation typically occurs over time. on the other hand, human factors and grassland management, especially crucial in maintaining its stability or degradation plays. Accordinglymonitoring vegetation winter pasture areas was conducted in Ardabil Province from 1387 to 1391. In each community a key area was determined to establish a permanent site, In each key area of the canopy cover, density and abundance during the three transects 500 m in 30 plots (1/20 × 1/20 meter) as well as soil moisture and organic carbon were measured. The results showed that a four-year period, proportional to changes in rainfall and temperature, Under local management conditions, In Moqan sites of Artemisia fragrans with absolute dominance and renewed growth. In direct response to the seasonal and annual rainfall and vegetation cover has a decisive role the results of the survey year to year changes in vegetation,climate changes from year to year and soil moisture also how the soil erosion condition can as an appropriate guide to the correct current methods used for management of rangeland ecosystems.
Amir Mirzaie Mousivand; Ardavan Ghorbani; Mohammad ali Zare Chahooki; Farshad Keyvan Behjoo; Kiomars Sefidi
Volume 24, Issue 4 , January 2018, , Pages 791-804
Abstract
The aim of this study was to investigate the effects of environmental factors on distribution of Prangos uloptera in rangelands of Ardabil province. The habitats of Prangos were identified and the habitats, in which the study species was present, were selected. Sampling was also carried out in the vicinity ...
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The aim of this study was to investigate the effects of environmental factors on distribution of Prangos uloptera in rangelands of Ardabil province. The habitats of Prangos were identified and the habitats, in which the study species was present, were selected. Sampling was also carried out in the vicinity of each habitat where the study species was not present. Three transects of 100-m length were established, on which canopy cover percentage and density of species were measured within 10 plots of 4m2. Soil samples were taken from the beginning, middle and end of each transect. In sampling places, altitude, slope, aspect, and soil characteristics were measured. Independent t test and cluster analysis were applied to comparison and classification of presence and non-presence areas and determination function was applied to determine the importance of factors affecting the presence of this species. The results of t test showed that there were significant differences between all variables except for temperature and precipitation. According to the results of cluster analysis, the studied species had more distribution in places with high altitude and steep slopes, high organic matter, and high nitrogen and sand. The results clearly showed that climatic parameters including precipitation and temperature as awell as altitude and sand percentage in the first grade and then aspect and soil characteristics including nitrogen and phosphorus in the second grade were the most important factors affecting the distribution of study species. According to the results, better decisions could be taken to use this species for range management, improvement and reclamation.
ardashir pounrnemati; ardavan ghorbani; jaber sharifi; farzad mirzaie; masoume amirkhani; mahmoud goudarzi
Volume 24, Issue 1 , May 2017, , Pages 110-125
Abstract
The purpose of this study was to investigate the relationship between rangeland plants production based on total production and life forms of grasses, forbs, and shrubs with topographic factors (altitude, slope, and aspects) in Sabalan rangelands, Ardabil province. To determine the annual total production, ...
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The purpose of this study was to investigate the relationship between rangeland plants production based on total production and life forms of grasses, forbs, and shrubs with topographic factors (altitude, slope, and aspects) in Sabalan rangelands, Ardabil province. To determine the annual total production, the amount of production was estimated using harvesting method in one square meter plots (totally of 216 plots) under the altitude range of 1200 to 2900 meters a.s.l. Using topographic maps, the digital elevation model was derived and classified maps of elevation, slope, and aspect were derived. Then, in each plot, information such as elevation, slope, and aspect was extracted. The correlation between life forms and topographic factors was analyzed using multivariate regression method. The results showed that there was a significant relationship between the production of life forms such as grasses (P<0.01), forbs (P<0.01) and shrubs (P<0.05) with topographic factors; however, there was no significant relationship between total production and topographic factors (P>0.05). The production of grasses, forbs and total production had direct relationship with slope; however, the production of shrubs decreased with the increase of slope. The production of grasses increased with altitude, and in the east-faced slopes, it was estimated more than the other aspects. The production of forbs decreased with the increase of altitude and was higher in the east aspect in comparison with the other aspects. The production of shrubs and total production in the middle altitude and in north –faced slopes were more than the other classes and aspects according to the suitable ecological condition and low degradation. Although it is obvious that elevation, slope, and aspect can change and affect the production, this effect is unknown, especially in the connection with life forms and the process of change. Overall, it can be concluded that these results could be used in the management of these rangelands, particularly in the improvement and rehabilitation practices.
ardavan ghorbani; ardashir pournemati; mohsen panahande
Volume 24, Issue 1 , May 2017, , Pages 165-180
Abstract
The aim of this study was to estimate and map the plant group and total aboveground phytomass using Landsat 8 images in the rangelands of Sabalan Mountain. Images were selected on the 19th of July 2013 and field data were collected in April and July based on maximum matching with the phenology of the ...
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The aim of this study was to estimate and map the plant group and total aboveground phytomass using Landsat 8 images in the rangelands of Sabalan Mountain. Images were selected on the 19th of July 2013 and field data were collected in April and July based on maximum matching with the phenology of the study area and in the closest date to the time of image acquisition. Twenty-four sampling sites on six vegetation types were determined. In each site, 9 sampling plots, based on previous studies, which are required for minimum sample number according to the variance of vegetation distribution, were determined in a systematic-random method, and the aboveground phytomass of vegetation groups, such as grasses, forbs, shrubs and total, were determined using the harvesting method. Initially, to calculate vegetation indices, the averages of 16 pixel values of the location of sample units from the corrected images were derived and transferred to the software environment. The correlation matrices between the derived pixel values and field collected data for the 24 selected vegetation indices were calculated and used for the estimation of grasses, forbs, shrubs and total aboveground phytomass. The results showed that indices such as RVI, TNDVI and GNDVI had the highest correlation with the aboveground phytomass of grasses, PD312, IO and PD311 with the aboveground phytomass of forbs, RDVI, DVI and RVI with the shrubs, and PD311, PD321 and PD312 with the total aboveground phytomass (P <0.01). In the second stage, three of the indices, having the highest correlation with the aboveground phytomass of each group and entire previous stage, were selected, and Landsat8 images were used to calculate the aboveground phytomass of each vegetation group and the total aboveground phytomass was calculated. The aboveground phytomass maps of each group and the total aboveground phytomass were controlled with sampling points to assess the accuracy. The results of this study showed that the best maps were obtained using the TNDVI index for grasses aboveground phytomass, PD312 for forbs, RVI for shrubs groups and PD311 for the total aboveground phytomass. Moreover, some indices, such as PD311 and RVI, could be used for all growth forms and estimation of total aboveground phytomass (P<0.01) and (P<0.01). In general, Landsat 8 data could be used to estimate and map the aboveground phytomass of vegetation groups and to determine the carrying capacity of the total aboveground phytomass in Sabalan rangelands, having advantages based on cost, time and the ability to monitor large areas with repeatability potential in comparison with the ground-based methods.
Ardavan Ghorbani; Baharak Zare Hesari
Volume 23, Issue 3 , January 2017, , Pages 454-472
Abstract
This study was aimed to determine the feasibility of spatial statisticsin studying the spatial variations of density, canopy cover, and production for Artemisia fragrans in the southeast slopes of Sabalan. Initially, the normality test was conducted using SPSS16 software. Then, spatial statistical analysis ...
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This study was aimed to determine the feasibility of spatial statisticsin studying the spatial variations of density, canopy cover, and production for Artemisia fragrans in the southeast slopes of Sabalan. Initially, the normality test was conducted using SPSS16 software. Then, spatial statistical analysis including studying the spatial variability of density, canopy cover, and production of the studied species were conducted through the variograms of data and mapping the parameters using different interpolation and spatial statistical methods in the GS+5 and ArcGIS10 software. The accuracy assessment of maps was done using cross validation and three methods including: Root Mean Squared Error (RMSE), Mean Bias Error (MBE), and Mean Absolute Error (MAE). Results showed that the exponential model was the best-fitted variogram model and the data had high spatial structure. Among spatial statisticalmethods, the ordinary and universal co-kiriging were the best methods for the three parameters studied. According to the maps produced from these methods, A. fragrans is mostly distributed on the central and northeast parts and in low altitudes. Overall, spatial statistical techniques could be applied to zone the perennial key species of rangelands with proper sampling units.
Ardovan Ghorbani; Ali Asghari
Volume 21, Issue 2 , August 2014, , Pages 368-381
Abstract
The relationship between the distribution of Festuca ovina and ecological factors such as topography, climatic and edaphic characteristics was investigated in 45 sites of Southeastern rangelands of Sabalan in Ardabil province.Within the determined sites, three large plots of ...
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The relationship between the distribution of Festuca ovina and ecological factors such as topography, climatic and edaphic characteristics was investigated in 45 sites of Southeastern rangelands of Sabalan in Ardabil province.Within the determined sites, three large plots of 10 × 10 m, 40 meters away from each other, were established along a 120–meter transect from lower slopes to highlands. The measurement of canopy cover parameters was performed in three plots with dimensions of 60 × 25 cm within the middle plot and the lower and upper plots were used as control. Different parameters including altitude, slope and aspect were calculated and averaged for three plots. In the middle plot, a soil profile was dug to a depth of 30 cm and soil samples were collected from two depths of 0-15 and 15-30 cm to measure soil parameters. Cluster analysis and principal components analysis (PCA) were used to classify the sites and the importance of parameters was determined by discriminate analysis (DA). Using multivariate analysis, the study sites were classified into four groups.The sites having high canopy cover percentage of F.ovina were classified in group 3, in which altitude, slope, and precipitation were higher than those of other groups, while temperature, salinity and pH were lower. This shows that this species is more compatible to higher altitudes and lower temperatures and dose not tolerate soil salinity. It is more compatible to a pH of 7.1 to 7.3. Organic matter, phosphorus and potassium will provide better conditions for growth. Results of principal component analysis showed that the two main components could explained 95% of the data variations, and the classification of sites using these two components confirmed the results of cluster analysis. According to the obtained results, the distribution of F.ovina was affected by several ecological factors including temperature, climate, soil, and aspect.