massoud Borhani; Zahra Jaberolansar
Volume 25, Issue 1 , April 2018, , Pages 191-200
Abstract
Plant species diversity always implies ecosystem stability against environmental and biological disturbances. This study was conducted to investigate the effects of grazing management on diversity indices of plant species in grazed and exclosed rangeland sites of Hanna station- Semirom. ...
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Plant species diversity always implies ecosystem stability against environmental and biological disturbances. This study was conducted to investigate the effects of grazing management on diversity indices of plant species in grazed and exclosed rangeland sites of Hanna station- Semirom. Sampling was performed using 30 plots (1 m2) along four transects. Canopy area and density of species were recorded in sampling units, and the floristic list was provided in the whole area. Species richness, heterogeneity and evenness indices were calculated from density data and parametric diversity indices including log normal, geometric, and broken stick were fited in both exclosed and grazed areas. The Chi-Square test was used to examine the significance of measured traits. The results of numerical indices showed a higher species richness, evenness and species diversity indices in grazed than in the ungrazed site. The logarithmic diagram in the exclosed and grazed areas followed the broken stick model, indicating the presence of dominant species. The floristic lists of the study sites showed that the number of specific plant species in the grazed site was higher than that of exclosed site. Overall, the results showed that moderate grazing conditions in Hanna station improved plant species diversity indices and increased climax plant species.
massoud Borhani; Hosein Arzani; zahra jabeolansar
Volume 24, Issue 2 , July 2017, , Pages 249-258
Abstract
Range management method (RMM) is an important element of range management especially in the case of revegetation and rehabilitation of vegetation. This study aimed to investigate proper RMM and grazing systems for paddocks of Semirom in Esfahan province and comparing them with programs proposed by the ...
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Range management method (RMM) is an important element of range management especially in the case of revegetation and rehabilitation of vegetation. This study aimed to investigate proper RMM and grazing systems for paddocks of Semirom in Esfahan province and comparing them with programs proposed by the offices of natural resources. For this purpose, 29 paddocks under range management plan were selected and proposed RMM and grazing systems were defined. According to range condition and trend in the mentioned paddocks, RMM and grazing system maps were prepared using standards the defined theoretically. The results showed that in most cases, the proposed range management method in rangelands was consistent with the correct method based on rangeland condition. On the other hand, for 20 range management plans, despite artificial RMM, grazing system was predicted, which was not based on correct range management. Our results clearly showed that the proposed grazing systems were not implemented practically in range management plans of the study area due to technical difficulties in range parceling and controlling. In addition, in these areas, grazing schedule in accordance with grazing system does not have considerable advantages.
Fateme Hadian; reza jafari; hosein bashari
Volume 22, Issue 4 , March 2015, , Pages 730-744
Abstract
Urbanization has been a major factor of natural resource degradation in the Semirom region of Isfahan province. This study aimed to evaluate the impact of urban development through land cover/ land use changes over a 37-year period using Landsat 1976 MSS and 2013 TM images and population data. First, ...
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Urbanization has been a major factor of natural resource degradation in the Semirom region of Isfahan province. This study aimed to evaluate the impact of urban development through land cover/ land use changes over a 37-year period using Landsat 1976 MSS and 2013 TM images and population data. First, necessary processing (geometric, radiometric, and topographic) was applied on images. Then, by using field assessment and GoogleEarth software, sample points were selected. The land use/ cover maps of the region and their changes were extracted by maximum likelihood classifier and post classification methods and their accuracy were assessed through overall accuracy and Kappa statistics. The accuracy assessment showed that the accuracy of maps in 1976 and 2013 was about (overall accuracy) 80% and 92%, respectively. The population was increased during three decades from 41973 to 65047 persons, which has led to an increase of 0.90 and 0.26 in the urban, and agriculture area and a 3 percent decrease of rangeland area. The 2.5 fold increase in bare land area in 2013 in comparison with 1976 indicated the severity of land degradation in the study area. Overall, drought and urban area attractions have facilitated the migration of people from villages to the city and had considerable negative effects in natural resources. Therefore, the region requires a holistic approach in all economic, social, and environmental developments.
Masoud Borhani; Hosein Arzani; Mehdi Basiri; Mohammad Ali Zare Chahouki; Mehdi Farahpour
Volume 21, Issue 3 , December 2014, , Pages 530-540
Abstract
In order to investigate the effects of range management plans on cover, production, litter, and regeneration of plants in Semirum rangelands, 54 sites including 29 with plan and 25 without plan were selected. The implementation of range management plans resulted in the decrease of stocking rate, affecting ...
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In order to investigate the effects of range management plans on cover, production, litter, and regeneration of plants in Semirum rangelands, 54 sites including 29 with plan and 25 without plan were selected. The implementation of range management plans resulted in the decrease of stocking rate, affecting the improvement of vegetation. According to the obtained results, no significant differences were found for the mean total cover, production and number of seedlings between two managements (P<0.05), while in the sites with plan, the cover, production and number of seedlings of class 1 plants, and cover and production of perennial grasses were significantly more than those of the sites without plan. This result was also true in the case of litter. These variations in plant composition were due to the impact of controlling the intensity and timing of grazing on the competition between palatable and perennial species with invasive and annual ones.
Rooh... Kazemi; Hassan Yeganeh; Jamal.. Khajedin
Volume 18, Issue 1 , May 2011, , Pages 124-138
Abstract
Accurate and up-to-date global land cover data sets are necessary for various global change research studies including climatic change, biodiversity conservation, ecosystem assessment, and environmental modeling. The aim of the present research was to study change detection of vegetation during the grazing ...
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Accurate and up-to-date global land cover data sets are necessary for various global change research studies including climatic change, biodiversity conservation, ecosystem assessment, and environmental modeling. The aim of the present research was to study change detection of vegetation during the grazing season using multi temporal data of WiFS in Semirom region. Various preprocessing, including geometric correction were applied using topographic maps of 1:250000 with an RMSe 0.35 pixel for sensor IRS-WiFS. The atmospheric and topographic corrections were carried out using dark-object subtraction method and the Lambert method. Field data collection was started on June 2005 on 800,000 ha. Multi-temporal data of IRS-WiFS sets were used for this study. Image processing including FCC, PCA, vegetation indices and supervised classification were employed to produce the vegetation canopy cover map. Various vegetation types were sampled using stratified random sampling method. twenty random sampling points were selected and canopy cover percentage was estimated. Digital data and the indices maps were used as independent data and the field data as dependent variables. The produced models were processed and then resulted images were categorized in 5 classes. Also post classification method was used to determine change detections. Finally the produced maps were controlled for their accuracies. The results confirmed the high correlations of used WiFS indices with field data. In the current study, more than 30 percent of the study area has been affected during the grazing season. Also the NDVI, SAVI and DVI indices which employ RED and NIR bands had relatively highly correlations with rangeland data. Result showed vegetation maps produced with IRS-WiFS data set had very high accuracy.
Ahmadreza Ranjbari; Mohsen Rasti; Mohammad Javaheri
Volume 9, Issue 2 , September 2001, , Pages 833-846