Mahshid Souri; Mohammad Fayaz; Nadia Kamali; Saeedeh Nateghi
Volume 25, Issue 4 , February 2019, , Pages 911-922
Abstract
The main objective of this research was to evaluate vegetation changes and soil indicators in the Kalat Sadat Sabzevar area under rangeland management practices. Vegetation factors including plant species production, vegetation cover, cover percentage, litter percentage, plant ...
Read More
The main objective of this research was to evaluate vegetation changes and soil indicators in the Kalat Sadat Sabzevar area under rangeland management practices. Vegetation factors including plant species production, vegetation cover, cover percentage, litter percentage, plant species density, and rangeland condition and trend were measured at the exclosure site and adjacent control site. The assessment was conducted using a random-systematic method with a sufficient number of samples and appropriate distribution of samples at the time of rangeland readiness. The rangeland trend was determined on the basis of two methods, and rangeland condition was determined based on the four-factor method. Soil sampling was carried out at a depth of 20 cm. A total of 12 soil samples were taken from the first, second and third transects (exclosure site), as well as fourth, fifth and sixth (control site). Data were analyzed by the independent t-test using SPSS software. According to the obtained results, the highest canopy cover percentage in terms of palatability belonged to class II plants (19.37), and in terms of vegetative form belonged to the perennial plants (16.2). Also, the largest share of production in the exclosure site and grazing site was related to shrubs and perennial grasses, respectively. The results showed that clay, silt, lime, organic carbon, nitrogen and electrical conductivity were significantly different at 5% level between the exclosure and grazing sites, but there was no significant difference between acidity and phosphorous. Therefore, exclosure could be recommended as an improvement practice to be carried out in more areas of the region.
shahla Ghaderi; Alireza Amirian Chekan; Amaneh Karim Zadeh; Masoume Difrakhsh; Javad Pourrezaie
Volume 24, Issue 3 , October 2017, , Pages 478-493
reza Hasanpouri; Ali Tavili; seyed akbar javadi
Volume 23, Issue 4 , March 2017, , Pages 800-809
Abstract
Identification of effective environmental factors in distribution and establishment of plant species plays an important role in rangeland ecosystems management. The purpose of this study was investigation of reasons for plant species distribution and relationship between index species in Khorramabad ...
Read More
Identification of effective environmental factors in distribution and establishment of plant species plays an important role in rangeland ecosystems management. The purpose of this study was investigation of reasons for plant species distribution and relationship between index species in Khorramabad rangelands and physical and chemical properties of soil. At preliminary inspection, vegetation types were separated and the key area of each type was recognized. Four vegetation types were identified as follows: Agropyron libanoticum-Acantholimon bromifolium ،Hordeum glaucum-Taeniatherum crinitum، Astragalus adscendens-Agropyron trichophorum andAstragalus adscendens-Daphne mucronata. The size and number of sampling plots were calculated to be 4 square meters with minimal area method, and 160 based on the statistical formula, respectively. Sampling method in each vegetation type was randomize-systematic, so that, in each plot, vegetation factors were measured, then at the beginning and end of each transect a profile was dug and some physical and chemical properties of soil were measured. Vegetation ordination was done by CCA method and results showed that organic matter, nitrogen, phosphorus, potassium and pH were the most important factors affecting Daphne mucronata distribution. The distribution of Agropyron libanoticum and Acantholimon bromifolium were affected by potassium, soil texture, and EC. As well, soil texture and lime had a decisive role in distribution of Taeniatherum crinitum, Hordeum glaucum, Astragalus adscendens and Agropyron trichophorum.
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, ...
Read More
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 ...
Read More
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.
Amir Hosein Parsamehr; Mohammadreza Vahabi; zahra Khorovani
Volume 22, Issue 1 , June 2015, , Pages 194-203
Abstract
Vegetation cover is one of the most important factors for ecosystem sustainability; thus, recognizing and understanding factors affecting the establishment and distribution of vegetation communities are necessary. This study was aimed to determine the relationship between vegetation and soil parameters ...
Read More
Vegetation cover is one of the most important factors for ecosystem sustainability; thus, recognizing and understanding factors affecting the establishment and distribution of vegetation communities are necessary. This study was aimed to determine the relationship between vegetation and soil parameters of Ardestan rangelands, Isfahan Province. Primarily, the vegetation types were distinguished in the field using physiognomic method. Plot size was determined applying minimal area method. The number of plots was determined using statistical method. Systematic randomized sampling was used and performed along three transects of 100 m length. Ten plots of 6m2 were established along each transect at 10-meter intervals. Three soil profiles were dug in each area and soil samples were taken at a depth of 0-150 cm to study 21 soil factors. The results of factor analysis showed that among variables studied, 17 variables were the most effective factors on vegetation types of the study area. To determine the effect of environmental factors on the establishment of vegetation, canonical correspondence analysis was used applying CANOCO software. Ordination results showed that environmental factors such as soil texture, lime, potassium and electrical conductivity had the most important role in the establishment and expansion of plant communities in the study area.
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 ...
Read More
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.
Razieh Mohammadi; Kamaladdin Naseri; Gholamali Heshmati
Volume 21, Issue 1 , June 2014, , Pages 119-127
Abstract
This study was conducted to investigate the effects of Haloxylon aphyllum plantation on natural plant communities and soil properties of Abbas-Abad area in Khorasan Razavi Province. For this purpose, Haloxylon plantation and control areas were selected to compare with each other. In each area, fifty- ...
Read More
This study was conducted to investigate the effects of Haloxylon aphyllum plantation on natural plant communities and soil properties of Abbas-Abad area in Khorasan Razavi Province. For this purpose, Haloxylon plantation and control areas were selected to compare with each other. In each area, fifty- meter transects were located by random-systematic method. Measurements were done by point sampling method. Eighteen soil samples were collected from Haloxylon plantation and control areas to determine EC and pH values in the laboratory. Data were analyzed by t-test. According to the results, although higher species diversity was significant in Haloxylon plantation area (P<0/05), Haloxylon caused the replacement of non-native communities, so that only 64.28% of species composition in Haloxylon plantation area was similar to the control area. On the other hand, higher soil pH and EC in Haloxylon plantation area was significant (P<0/01) and probably in the long term, Haloxylon causes the salinity and alkalinity of the soil surface.
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 ...
Read More
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 ...
Read More
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.
Zainab Nurikiya; Akbar Javadi; Akbar Fakhireh; Ali Tavili; Mohammad ali Zare chahouki; Hamid reza Abbasi
Volume 16, Issue 4 , January 2010, , Pages 574-585
Abstract
The purpose of this research was to compare the amount of N, P and K in the soil under three rangeland species i.e. Agropyron tauri, Astragalus ammodendron and Bromus tomentellus and (with) the soil properties of the control area. After identifying the habitats (sites) of the mentioned species, soil ...
Read More
The purpose of this research was to compare the amount of N, P and K in the soil under three rangeland species i.e. Agropyron tauri, Astragalus ammodendron and Bromus tomentellus and (with) the soil properties of the control area. After identifying the habitats (sites) of the mentioned species, soil sampling was done in all key areas at the end of the growing season based upon randomized systematic method. In order to study the features of the mentioned species, 10 plots (1 m2) were established along 4 transects.Soil sampling was carried out in the beginning and in the end of all transects from 0-10 and 10-40 cm soil depths. Soil sampling was also done in the control area and then N, P and K were measured. All data were analyzed and compared by T test. The results indicate that the amount of N, P and K in the first soil depth beneath Agropyron tauri is more than that in Astragalus ammodendron and Bromus tomentellus. In most cases the amount of N and K in the soil beneath (under) the species are more than that in the control area which indicates the increase of fertility in the soil beneath the species in comparison to the control area and it can be due to the litter fall or intensified biological activities of the organisms.