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Volume 9, Issue 4 , July 2020, , Pages 105-139
Ayad Aazami; Morteza Akberzadeh; Mashaallah Mohmadpour
Volume 27, Issue 1 , April 2020, , Pages 1-12
Abstract
Rangeland capacity depends on forage produced in the rangeland, the permitted range of plant species, forage quality and rangeland health. Range species have a certain production in months and years. Without recognize properties production plants and the rate consumption forage rangeland cannot programming ...
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Rangeland capacity depends on forage produced in the rangeland, the permitted range of plant species, forage quality and rangeland health. Range species have a certain production in months and years. Without recognize properties production plants and the rate consumption forage rangeland cannot programming and management at during a period of grazing. This study was conducted at 2009-2013 years, and rate forage production and utilization was measured. The rate of precipitation annual at 3 years were 138, 200 and 330 millimeter respectively. The results showed that total forage production was significantly different between years (p<0.01). Forage production were 485.7, 1372 and 1844.4 Kg per hectare respectively. The amount of production in the months of growing season (March to August) were significantly different, so 94.7 of pasture growth in the first 2 months (March and April) and three fifths% by feed-in last 4 months. The annual consumption of respectively 400 and 751 and 490 kg per hectare. Although not statistically significant, But in the dry year of 2008, 83% and in the wet year of 1389, 26.6% were used of pasture production. Therefore, in drought, at the same time as the reduction in forage production, the livestock utilization rate increased by 83%, which is not proportional to the rangeland capacity. Therefore, in order to achieve sustainable production, proper management of rangeland and the use of indigenous species such as Onosma bulbotrichum, Ankyropetalum gypsophiloides, Convolvulus reticulatus and Salvia compressa are recommended.
reza siahmansour; Morteza akbarzadeh; Ehsan Zandi Esfahan
Volume 24, Issue 2 , July 2017, , Pages 418-428
Abstract
This research was carried out at the Zagheh research station in Lorestan province. A number of 440 individuals in each year and 2200 individuals in five years were cut and weighted inside and outside the exclosure. The difference in weight between the individuals outside and inside the exclosure indicates ...
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This research was carried out at the Zagheh research station in Lorestan province. A number of 440 individuals in each year and 2200 individuals in five years were cut and weighted inside and outside the exclosure. The difference in weight between the individuals outside and inside the exclosure indicates the amount of consumption. According to the results, there is a significant difference between the mean value of forage production and consumption in months and in different species (P<0.01). For the average of four years, the highest and lowest forage production was recorded in the third and second year, respectively. On average, forage production was calculated to be about 1,177 kg per year. On average during four years, 80% of the production was used by livestock. In all years, the highest amount of forage was produced in May. Ono.melanotricha, As. Remotijogus and As.bungei are consumed up to the basal area, while the highest consumption rate for Cen.virgata was obtained in June. Perennial grasses of the study site like Hor. bulbosum, Br.tomentellus, Festuca ovina, Stipa wiesnerii are also under severe grazing pressure. Under heavy grazing over a season, some species like Picris strigosa are not able to rejuvenate and their roots are shattered with little stress. Therefore, the imbalance between production and exploitation and inappropriate distribution is a major factor in the degradation of vegetation and rangeland ecosystems.
Morteza Khodagholi; Morteza Akbarzadeh
Volume 23, Issue 1 , June 2016, , Pages 118-127
Abstract
This study was conducted to demonstrate the growth behavior of Andrachne fruticosus L, Artemisia sieberi Besser، Euphorbia decipiens Boiss and Buhse، Noaea mucronataForssk، Scariola orientalis Sojak، Stachys inflate Benth، Stipa arabica Trin & Rupr and annual species in the Soh rangelands of ...
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This study was conducted to demonstrate the growth behavior of Andrachne fruticosus L, Artemisia sieberi Besser، Euphorbia decipiens Boiss and Buhse، Noaea mucronataForssk، Scariola orientalis Sojak، Stachys inflate Benth، Stipa arabica Trin & Rupr and annual species in the Soh rangelands of Meimeh, Isfahan during 2008 to 2010. To determine the production and consumption of the study species, a number of eight individuals for each species were selected for all months of growing and grazing season within the exclosure area as well as in the grazing area. Results showed that different years and months had significant effect on production of the study species (p < 0.01). According to the results recorded during the experiment, the average production of six perennials and annuals was calculated to be 255.9 kg dry forage per hectare. The highest production rate was obtained for Artemisia sieberi and annuals, 38.2% and 32.9% of total forage production, respectively. Production changes were totally affected by changes in the volume and distribution of rainfall and the correlation coefficient between them was statistically significant in all species except Euphorbia decipiens. The production of the study species showed high fluctuation in response to the most severe drought in 2008. Forage production of the study species in the high-production year was 4.5-20 times higher as compared with the low-production year. For all species, the highest forage production was obtained in May. The consumption rate varied in different years and the highest consumption was recorded in 2009 for all species except Euphorbia decipiens. As well, the highest consumption rate was recorded for annuals during the three study years.
Morteza Akbarzadeh; Mohammed Reza Moghadam; Adel Jalili; Mohammad Jafari; Hossein Arzani
Volume 13, Issue 4 , February 2007, , Pages 324-336
Abstract
The pressure of livestock grazing and overall utilization of rangelands have caused vegetation and soil degradation in many natural rangelands of Iran. Grazing prevention is one of the rangelands rehabilitation methods, which is effective in renovation of rangelands. The effect of 24 years of grazing ...
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The pressure of livestock grazing and overall utilization of rangelands have caused vegetation and soil degradation in many natural rangelands of Iran. Grazing prevention is one of the rangelands rehabilitation methods, which is effective in renovation of rangelands. The effect of 24 years of grazing protection were studied on vegetation dynamics of Kuhrang region, in two years growing seasons (2003 and 2004). Parameters from rangelands characteristics were collected and analyzed. Results showed that after 24 years livestock exclusion in Kuhrang, total inside canopy cover was higher than outside (P<0.01). Grasses and forbs were higher inside than outside (P<0.01), but shrubs were not significantly different (P>0.05). Over half of inside canopy cover belonged to decreasers and increasers, which were little or negligible outside of exclosure and 95 percent of outside plant composition belonged to invaders. Most desirable species had greater inside cover than outside(P<0.01). Klucia odoratassima, Scorzonera calyculataand Delphinium cyphoplectrumhad greatest inside canopy cover, than other forbs. More than half of inside and 95 percent of outside cover referred to decreasers and increasers. Approximately 38 and 1.2 % of inside and outside forage production belonged to decreasers and increasers respectively. Regeneration was higher outside of exclosure in Astragalus adscendens, in first year. Litter was higher inside and bare soil outside the exclosure (P<0.01). Inside and outside range condition was good and very poor, respectively.
Morteza Akbarzadeh; Taghgi Mirhaji
Volume 13, Issue 3 , February 2006, , Pages 222-235
Abstract
Study of vegetation changes of ungrazed rangelands is important. It is supposed that ungrazed areas tends toward climax and range condition to be improved. The major portion of our rangelands are laied in arid and semi-arid regions. For that precipitation is the major influential factor on vegetation ...
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Study of vegetation changes of ungrazed rangelands is important. It is supposed that ungrazed areas tends toward climax and range condition to be improved. The major portion of our rangelands are laied in arid and semi-arid regions. For that precipitation is the major influential factor on vegetation changes. In dry years as rainfall decreases, the vegetation cover are damage. This study were conducted on Rudshur rangelands for nine years (1996-2004), with the aim of rainfall variation and ungrazed condition effects on vegetation changes. Plant parameters as canopy cover, density and seedling numbers were estimated on permanent plots each year. A dry period were started in 1997 in the region and continued for five years. Results showed, in a period of nine years, total canopy cover declined 40 percent. Decline of canopy cover varied from 26 to 95 percent for different species. Only canopy cover of the Poa sinaica increased about three times, due to earliest vegetative period in growing season. Decline in canopy cover was greatest in forbs, and grasses had lower decline. Regeneration was high in the rainy years and 81 percent of total seedlings belonged to grasses especially to Stipa hohenackeriana. Density of most species decreased in the study period especially in dry years.