Jaber Sharifi; Morteza Akbarzadeh
Volume 26, Issue 1 , June 2019, , Pages 40-48
Abstract
Knowing the ecological characteristics of plants and consequently changes in forage production during the season of grazing for grazing management is essential. Therefore, understanding the annual and monthly production of different rangeland types is essential for efficient ...
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Knowing the ecological characteristics of plants and consequently changes in forage production during the season of grazing for grazing management is essential. Therefore, understanding the annual and monthly production of different rangeland types is essential for efficient and effective forage management. Consequently, relationships between forage production and climatic variables should be considered. For this purpose, the annual forage production was measured in the research exclosure of Arshaq Site rangelands in Ardabil province during 2007-2010 by clipping and weighing method. The monthly rainfall in this period was calculated using Mashkin-Shahr synoptic station data and then the amount of cumulative rainfall in winter and spring of each year was calculated. Afterward, the relationship between production and winter and spring rainfall as well as rainfall of different months of winter and spring was studied separately. Statistical analysis was performed using SAS software. According to the results, the average forage production during four years was calculated of which 28.95% belonged to Artemisia fragrans, 26.35% to Kochia prostrate, 19.55% to Stipa hohenackeriana, 4.77% to Astragalus brachyodonuts and 20.38% to the other species. Analysis of variance showed that the production of species among years were significant (P<0.01). In terms of stability (interactions of year × month), Artemisia fragrans and Kochia prostrata were stable, with a high yield; however, Astragalus brachyodonuts and Stipa hohenackeriana were stable with a low yield.
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.