Amirhosein Kavianpour; zeynab Jafarian; Abazar Esmaeli Ouri; Ataollah Kavian
Volume 23, Issue 3 , January 2017, , Pages 593-605
Abstract
Soil is a suitable bed for plant growth and development of vegetation, so that if it is not conserved, it will result in the nutrient deficiency, soil erosion and degradation of natural resources. In this research, the spatial variability of some chemical and physical properties of soil was investigated ...
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Soil is a suitable bed for plant growth and development of vegetation, so that if it is not conserved, it will result in the nutrient deficiency, soil erosion and degradation of natural resources. In this research, the spatial variability of some chemical and physical properties of soil was investigated in different vegetation covers (minimum, moderate and maximum) and different grazing intensities including reference area (light grazing), key area (moderate grazing) and critical area (heavy grazing) in the winter rangelands of Nasho, Mazandaran province. Soil samples were collected from 0-30 cm depth according to a systematic grid (30×30 m) and then transferred to the laboratory. Soil chemical and physical properties including acidity (pH), Electrical Conductivity (EC), caco3, bulk density, particle density, total phosphorus, total nitrogen, available potassium, organic matter, initial moisture content, percentage of clay, silt and sand, sodium, calcium, and magnesium were measured in laboratory. In addition, soil surface resistance was measured in the field with a portable penetrometer. The results of statistical analysis showed that different grazing intensities had significant effects on organic matter, available potassium, pH, EC, caco3, calcium, bulk density, initial moisture content, and surface resistance of soil. Different vegetation covers had significant effects on silt percentage, organic matter, pH, EC, calcium and initial moisture content of soil.
Mohammadreza Habibian; ali saleh pour
Volume 23, Issue 2 , September 2016, , Pages 321-311
Abstract
This research was performed in semi-steppe rangelands of Fars province in the Cheshmeh Anjir region, in 2013. Soil sampling was performed in a random-systematic manner. In each area, three transects of 50 m were established randomly with a proper distance in an area of about two hectares, and on each ...
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This research was performed in semi-steppe rangelands of Fars province in the Cheshmeh Anjir region, in 2013. Soil sampling was performed in a random-systematic manner. In each area, three transects of 50 m were established randomly with a proper distance in an area of about two hectares, and on each transect, two soil profiles were dug. The soil samples were collected from two depths of 0-25 and 25-60 cm. The experiment was laid out in a split-plot in a randomized complete block design with three replications. The study area at three levels (key, reference and critical) and the sampling depth at two levels (0-25 and 25-60 cm) were considered as main factor and sub-factor, respectively. The statistical analysis was performed using SPSS software. Mean comparison was performed by Duncan's test. The results of this study showed a significant difference (p<0.01) among the grazing management regions in terms of soil physical and chemical properties including pH, organic carbon, sand, clay, and total nitrogen, so that pH and sand percentage increased and clay percentage decreased with increasing of grazing intensity. Meanwhile, with increasing of grazing intensity, organic carbon and total nitrogen decreased in the key area and then increased equivalent to that of reference area. Significant differences (P<0.01) were found between soil depths for the soil pH, and the percentage of sand, silt, phosphorus and total nitrogen. In addition, the percentage of organic carbon and total nitrogen varied significantly (P<0.01) among transects.
Farshad Keivan Behjou; Ehsan Zandi esfahan; Babak Mahboub
Volume 23, Issue 2 , September 2016, , Pages 356-344
Abstract
The Talesh summer rangelands is one the resorts affected by ecotourism activities at regional and national levels. This research was aimed to investigate the effects of ecotourism on soil changes. For this purpose, three recreational zones were selected in the rangelands of the study area with low, moderate, ...
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The Talesh summer rangelands is one the resorts affected by ecotourism activities at regional and national levels. This research was aimed to investigate the effects of ecotourism on soil changes. For this purpose, three recreational zones were selected in the rangelands of the study area with low, moderate, and high tourism pressure. Sampling was performed in a random systematic manner. In each zone, six transects of 10 m length were established randomly and on each transect, five quadrates of 25 cm2 were selected at a distance of two meters apart. To study soil physical and chemical properties, five soil samples were taken on each transect at a depth of 0-30 cm. The soil moisture content, volumetric moisture content, soil texture, pH, EC, bulk density, and phosphorus and potassium content were measured in the laboratory. Data analysis was performed using SPSS software and Duncan's test was applied to compare the means. According to the obtained results, significant differences were found for soil moisture content, volumetric moisture content, organic matter, pH, EC, bulk density, and soil saturation percentage among the three study zones.
Behnam Bahrami; Reza Erfanzadeh; Javad Moetamedi
Volume 22, Issue 1 , June 2015, , Pages 47-58
Abstract
Study on the effect of different grazing intensities on some soil characteristics could be helpful in management and conservation of soil and vegetation. In this study, six key areas were selected with different in grazing intensities. The grazing intensities level for Makueian sheep race was recognized ...
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Study on the effect of different grazing intensities on some soil characteristics could be helpful in management and conservation of soil and vegetation. In this study, six key areas were selected with different in grazing intensities. The grazing intensities level for Makueian sheep race was recognized based on the distance to the villageand the cover percentage of invasive, increaser and decreaser species. In each area, soil sampling was done along systematically established transects, in which 18 soil samples were collected from two depths (0-15 and 15-30 cm). Soil samples were then transferred to the laboratory for the chemical and physical analysis of 17 soil characteristics.The results of principle component analysis showed that silt percentage, coarse and fine aggregate percentage, saturation percentage, and particulate organic carbon of upper layer (0-15 cm) as well as soil texture, the carbon of coarse and fine aggregates, EC, and the bulk density of lower layer (15-30 cm) were more sensitive to sheep grazing as compared to other soil characteristics.
Elham Fakhimi Abarghouie; Seyed Akbar Javadi
Volume 21, Issue 1 , June 2014, , Pages 109-118
Abstract
From the perspective of rangeland ecology, awareness of the effects of livestock grazing on the changes of structure, plant vegetation and soil characteristics is essential. The aim of this study was to determine the effect of different grazing intensities including heavy (0-200 m distance from water ...
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From the perspective of rangeland ecology, awareness of the effects of livestock grazing on the changes of structure, plant vegetation and soil characteristics is essential. The aim of this study was to determine the effect of different grazing intensities including heavy (0-200 m distance from water point), moderate grazing (200- 800 m) and light grazing (800-1200 m) intensities on vegetation indices and soil characteristics in Nodushan region, Yazd province of Iran. For this purpose, plant vegetation cover and composition were recorded under three grazing intensities. Soil was sampled from depths of 0-30 cm. Data were analyzed by one way ANOVA, t-testandordination method (CCA) to assess the vegetation response in different grazing intensities. Results showed that plant species such as Astragalus achrochlarus, Salsola arbusculata and Tragopogon sp.were found in light grazing area.Allysum minus, Artemisia sieberi, Poa sinacia, Iris songarica, Lactuca glacifolia and Stipa barbata were identified in moderate grazing area. Eryngium sp., Cousinia desertii, Bromus tectorum and Peganum harmala were the major species in heavy grazing area.Soil properties including N, P, K, OC, EC and pH were measured. According to the results, nitrogen and soil organic matter were decreased by increasing grazing intensities but P, K, EC and pH were increased. Since grazing pressure causes damage to vegetation and some soil properties, a moderate grazing is recommended for sustainable utilization of rangelands.
Rasool khatibi; Yaser Ghasemi Arian; Esfandyar Jahantab; Mohammad Haji hashemi
Volume 19, Issue 1 , June 2012, , Pages 72-81
Abstract
Soil properties are of the effective factors in distribution of vegetation, especially in arid and semi arid regions as the effect of geology, topography and climatic factors appeare in soil properties. In this study, soil properties of rangeland vegetative types was studied in Dejinak-e-Khash in the ...
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Soil properties are of the effective factors in distribution of vegetation, especially in arid and semi arid regions as the effect of geology, topography and climatic factors appeare in soil properties. In this study, soil properties of rangeland vegetative types was studied in Dejinak-e-Khash in the southern of Taftan. Soil and vegetation sampling were done in key areas of each site by random- systematic method. Plot size was determined with minimal area method. Also, the size and number of transects for sampling were determined according to species and vegetation changes. Physicochemical properties of soil including soil texture, pH, electrical conductivity, lime and organic matter were measured. After measuring soil and plant factors, statistical analysis was performed on plant species, vegetation types and soil factors by SPSS software. Finally, the best equation and correlations were determined between vegetation types and soil parameters. Results showed that the percentage of organic matter, clay and absorbable potassium were the most important factors in distribution of key range species in the study area. In general, the results showed a significant relationship at 95% probability level for Artemisia siberi with potassium and clay, for Salsola nitraria with soil pH, and for Acanthophyllum microcephalum with total nitrogen. Also, the distribution of Hammada salicornia was significantly affected by all factors except P and EC at 95% probability level.
Farhad Zolfaghari; Ahmad Pahlevanravi; Akbar Fakhireh; Mitra Jabari
Volume 17, Issue 3 , October 2010, , Pages 431-444
Abstract
Agh Toghe basin is in the central part of Marave Tapeh located in the east of Golestan province. In this research, study area was investigated based on Braun-Blanquet to identify plant communities. Afterward, relationship between environmental factors particularly slope, elevation, vegetation cover and ...
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Agh Toghe basin is in the central part of Marave Tapeh located in the east of Golestan province. In this research, study area was investigated based on Braun-Blanquet to identify plant communities. Afterward, relationship between environmental factors particularly slope, elevation, vegetation cover and soil properties including sand, silt, clay, acidity, electrical conductivity, and organic matter were determined using Principal Component Analysis (PCA). .Data collecting was carried out through establishing 103 quadrates based upon minimal area method in different vegetation types. A matrix of vegetation and soil characteristics was prepared and ordination was applied by PCA. The results showed that the most important factors in separation of vegetation types were as follows: elevation, slope, carbon percentage, sand, silt, clay and acidity.