Farhad Aghajanlou; Morteza Akbarzadeh; ahmad mousavi; Parviz Moradi
Volume 28, Issue 4 , November 2021, , Pages 614-630
Abstract
Rangelands capacity depends on several factors, including the amount of forage production. Forage production varies during the grazing period and different years. The goal of determining grazing capacity is to estimate the forage production within the grazing period. This project was carried out over ...
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Rangelands capacity depends on several factors, including the amount of forage production. Forage production varies during the grazing period and different years. The goal of determining grazing capacity is to estimate the forage production within the grazing period. This project was carried out over a period of 4 years (2006-2010) to determine forage production and consumption at different stages of growth. For this purpose, at the beginning of grazing season, the amount of forage remaining after grazing until the exit time of livestock was harvested at one-month intervals. Forage production was measured within the enclosed and adjacent area, and the amount of consumption of each species was determined. The collected data were analyzed based on a completely randomized design. The combined analysis of variance showed that production was significantly different (P<0.01) in years and months of the growing season. The highest amount of production was recorded in 2009 and the lowest in 2008. The ratio of forage produced in unfavorable to favorable years was 50%. In other words, forage production in 2009 was double that of 2008. This ratio was 13% to 79% among species. The peak of monthly rangeland production was in June and was the same for most species. The average rangelands production at the four-year study was about 650 kg/ha, and the contribution of three species Festuca ovina, Bromus tomentellus, and Tanacetum polycephalum were 24%, 20%, and 11%, respectively. The highest forage consumption was recorded in July and then in August. On average, about 71% of forage production was consumed during the grazing season. The lowest and the highest forage consumption was observed for Phlomis olivier (37%) and Silene ampullata (100%), respectively.
Ahmad Mousavi; Ali Ehsani; Farhad Aghajanlou
Volume 23, Issue 2 , September 2016, , Pages 208-197
Abstract
Phenology studies are one of the appropriate tools to determine the utilization time of rangelands.This research was aimed to study the phenology of Festuca ovina in the Bademestan rangelands of Zanjan province, located at 45 km northeast of Zanjan for four years. The results showed that the study species ...
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Phenology studies are one of the appropriate tools to determine the utilization time of rangelands.This research was aimed to study the phenology of Festuca ovina in the Bademestan rangelands of Zanjan province, located at 45 km northeast of Zanjan for four years. The results showed that the study species had a very special reaction to the rainfall amount and time, especially during the growing season i.e., from the onset of spring to July. In other words, no reproductive growth and formation of flowers were recorded in 2007-2008, whose rainfall was much less than average during the growing season (57.2 mm in the spring quarter). A sharp decline in rainfall during the spring caused the species not to complete its phenology and produce seeds. The year 2009-2010 had much less rainfall as compared with the year 2007-2008; however, due to the good rainfall in spring 2010, Festuca ovina could complete all phenological stages and flowering stage occurred. Therefore, it seems that the spring rains are vital for this species to complete the plant life cycle.
Ali Shahbazi; Farhad Aghajanlou; Fatemeh Einlou; Mamak Ahmadian
Volume 21, Issue 4 , March 2015, , Pages 718-730
Abstract
Determining land capability based on land suitability, climatic characteristics, and soil physical and chemical properties is considered as a method of achieving sustainable management. In this study, FAO model was used to determine land capability. To describe the spatial results, Geographical Information ...
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Determining land capability based on land suitability, climatic characteristics, and soil physical and chemical properties is considered as a method of achieving sustainable management. In this study, FAO model was used to determine land capability. To describe the spatial results, Geographical Information System (GIS) was used. Spatial data, as maps, and descriptive data, as database table, were entered into the GIS environment. The results of current land suitability model for irrigated agriculture and garden land use showed that 64.5% was in N2 class, 17.86% in N1 class, 17% in S3 class and 0.64% in NR class. For dry farming land use, 64.5% was in N2 class, 18.86% in S3 class, 17% in S2 class, and 0.64% in NR class. For rangeland use, 32% was in S3 class, 32.5% in N1 class, and 35.5% in NR class. For forest land use, 64.5% was in N1 class and 35.5% in NR class. From overlaying the current land use map with the current land suitability map, it was found that only 25.5 % of irrigated agriculture land use, 82 % of dry farming land use and 30.3% of rangeland use were consistent with their land suitability map, being exploited properly
Farhad Aghajanloo; Mortezah Akbarzadeh; Ahmad Musavi
Volume 16, Issue 4 , January 2010, , Pages 493-504
Abstract
As the documents and reports reveal, the condition of rangelands of Iran is poor or very poor in most areas; therefore, the percentage of invader species is dominant. The study of vegetation changes under strict exclosure and grazing is critical to understand the extreme problems of rangelands of Iran. ...
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As the documents and reports reveal, the condition of rangelands of Iran is poor or very poor in most areas; therefore, the percentage of invader species is dominant. The study of vegetation changes under strict exclosure and grazing is critical to understand the extreme problems of rangelands of Iran. The effect of exclosure and grazing was studied on the direction of vegetation changes of rangelands at Arquin site of Zanjan province at 1450 meter above sea level from 2001 to 2006. Three fixed pairs of transects with a total number of 60 plots were established inside of exclosure area and outside too. The annual forage production was measured by randomized plots. Comparison of the data in first and last years of the study were done by T student sample test. The results showed that the total canopy cover of Arquin exclosure is increased inside in comparison with outside, and it is statistically significant (P<0.01). The response of growing forms to exclosure and grazing was different, and the canopy cover of Astragalus achtalensis (P<0.05) and Stipa barbata (P<0.01) increased significantly in 2006 in comparison with 2002. The vegetation composition changed also in the study area. The relative increase of increasers in last year, was by 160 percent to that of the first year inside the exclosure; whereas the changes were not apparent. The rate of plant production was specially depended on precipitation fluctuation and the amount of organic mater and nitrogen content at 0 to 15 cm of soil depth inside and outside of the exclosure and that of 15-30 cm outsid has been increased significantly.
Farhad Aghajanlou
Volume 9, Issue 2 , September 2001, , Pages 703-714