Robab Bagherian; Kiomars Sefidi; Farshad Keivan Behjou; Ali Ashraf Soltani; Behzad Behtari
Volume 25, Issue 1 , April 2018, , Pages 183-190
Abstract
To evaluate the effects of grazing on some physical and chemical properties of soil, in the summer rangelands of southern slopes of Sabalan, three regions with different grazing intensity were selected after field observation and 27 soil samples were randomly taken along three 200-m transects. Soil samples ...
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To evaluate the effects of grazing on some physical and chemical properties of soil, in the summer rangelands of southern slopes of Sabalan, three regions with different grazing intensity were selected after field observation and 27 soil samples were randomly taken along three 200-m transects. Soil samples were taken from the depths of 15-0, 30-15 and 45-30 cm and transported to laboratory and soil properties such as texture, organic matter, organic carbon, phosphorus, potassium, EC and pH were measured. Analysis of variance and mean comparison were made using Duncan's test. Results showed that no significant difference was found for soil pH and phosphorus among the grazing intensity treatments and soil depths; however, significant differences were observed for other variables. The results showed that organic matter content decreased with increasing of grazing intensity and the lowest content was recorded for the 30-45 cm soil depth in the heavy grazing area. According to the results of this research it can be concluded that soil structure is degraded with increased grazing intensity; therefore, a balanced grazing need to be taken into account in summer rangelands to prevent soil degradation.
Moharam Ashraf Zadeh; Reza Erfanzadeh; seyed hamzeh Hoseini Kahnooj
Volume 22, Issue 2 , August 2015, , Pages 381-391
Abstract
This study was carried out to compare the forage quality parameters (CP, DMD and ADF) in two phenological stages between two regions in south of Fars province. The two regions were located close together, and with the exception of soil characteristics, were similar in terms of other environmental factors. ...
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This study was carried out to compare the forage quality parameters (CP, DMD and ADF) in two phenological stages between two regions in south of Fars province. The two regions were located close together, and with the exception of soil characteristics, were similar in terms of other environmental factors. One region had a saline-alkali soil (pH= 8.30, EC=15.6, SAR=6.51, ESP=%2.84.) and the other region had an alkali soil (pH= 8.53, EC=1.24, SAR=4.18, ESP=%1.12.8). The common plant species were sampled. An independent t-test was used to compare the content of ADF, CP and DMD of forage in each phenological stage between saline-alkali and alkali soils. A paired t-test was applied to compare forage quality parameters between two phenological stages in each species separately. Results showed that in both phenological stages, halophytes such as Atriplex halimus and Seidlitzia rosmarinus had a better forage quality in alkali soils. Most species were not significantly different in forage quality parameters between the two regions. In vegetative growth stage, DMD and CP content in halophytes were higher in saline-alkali as compared to alkali soils, and ADF was also higher in saline-alkali than that of alkali soils for a few halophytes such as Seidlitzia rosmarinus. In flowering stage, except for Seidlitzia rosmarinus, digestibility of species was not affected by soil chemical properties. This study showed that some species had relatively more adaptation to harsh condition, and subsequently had higher forage quality. Therefore, the manager could identify these species and use for conservation purposes.
Maryam Heidarian Aghakhani; Ali asghar Naghipour Borj; Hosein Tavakoli
Volume 17, Issue 2 , September 2010, , Pages 243-255
Abstract
It is important to know soil propoerties, particulary its chemical aspects, for the proper management of rangeland ecosystems. The aim of this study is to find the impact of grazing on vegetation and some soil chemical properties, in three areas, the key, reference, and critical, Sisab rangelands, Bojnord. ...
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It is important to know soil propoerties, particulary its chemical aspects, for the proper management of rangeland ecosystems. The aim of this study is to find the impact of grazing on vegetation and some soil chemical properties, in three areas, the key, reference, and critical, Sisab rangelands, Bojnord. The vegetation cover data was collected from 30, 1m2 quadrats in each area through random –systematic method. The soil data was sampled from two depths 0-15, 15-30 cm and five composite samples were collected (each sample was mixed of six samples) from each depth in the each area. Some factors such as the organic carbon, the percentage of soil organic matters, total nitrogen, absorbable phosphorus, pH and EC were measured. The results showed that carbon, nitrogen, soil organic matters, phosphorus, and EC were been decreased by grazing, but pH was increased. According to results, forbs were the dominant life form in the reference site. Shrubs cover percentages were been increased as grazing increased. In addition, reference site had species that are more palatable and invaders were more abundant in critical area. It was concluded that heavy grazing intensity cause to decrease of vegetaton and conversion of composition of the species cause to negative conversion in alimentary mineral of soil, sustainable of ecosystem would be endangered.