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Volume 9, Issue 4 , July 2020, , Pages 105-139
Taghi Mirhaji; Msoud mohammad Aleyha
Volume 8, Issue 3 , September 2019, , Pages 65-88
Taghi Mirhaji; Morteza Akbarzadeh
Volume 10, Issue 2 , September 2019, , Pages 193-214
Hosein Arzani; Javad Motamedi; Taghi Mirhaji
Volume 25, Issue 3 , November 2018, , Pages 657-670
Abstract
Knowledge of the animal daily requirement in rangelands is one of the essential requirements to calculate the grazing capacity in rangeland plans. In this regard, the daily metabolizable energy requirements of different Sangesary sheep (ewe, ram, and lamb) were investigated. For ...
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Knowledge of the animal daily requirement in rangelands is one of the essential requirements to calculate the grazing capacity in rangeland plans. In this regard, the daily metabolizable energy requirements of different Sangesary sheep (ewe, ram, and lamb) were investigated. For this purpose, according to the average values of forage quality indices and the proportion of species in the plant composition, the amount of metabolizable energy in one kilogram of dry forage at different growth stages was estimated, and considering the daily metabolizable energy requirement, the amount of forage that supplies the animal was estimated. The daily metabolizable energy requirement was calculated according to the proposed MAFF (1984) equation under grazing condition regarding the physical properties of the rangelands, water distribution intervals, plant density, and applying an incremental coefficient of 70%. Based on the results, the amount of forage needed to meet the daily needs of the ewe of the Sangesary sheep with a mean weight of 37 kg in the early, mid, and late growing season was estimated to be 1.6, 2.1 and 2.3 kg dry matter, respectively. The values for adult rams with an average weight of 48.75 kg were estimated to be 1.9, 2.5 and 2.9 kg in different growth stages. The lambs' daily requirement with an average weight of 19.88 kg was estimated to be 1.3, 1.7, and 1.9 in each growing season. The results showed that considering the amount of 1.5 kg of dry matter forage to meet the daily requirements of different kinds of animals grazing in rangelands is not correct and animal requirement need be determined based on forage quality in phenologiacal stages.In addition, the results emphasize that in order to adapt the daily requirements of animal to the forage quality, it is necessary to consider the values of forage quality indices and the proportion of all species grazed in the plant composition, so that the results should not be limited to the species in animal diet. Otherwise, as in the present study, the estimated requirement is more than the daily intake of animal grazing on rangelands.
Taghi Mirhaji; Farhang Ghasriani; Farhad Azhir
Volume 23, Issue 2 , September 2016, , Pages 274-265
Abstract
This research was aimed to determine the best harvesting intensity for key and indicator species including Agropyron intermedium, Oryzopsis holciform, and Thymus fedtschenkoi in the cold semi steppe rangelands of Firoozkooh. Treatments consisted of different harvesting intensities of 25%, 50%, 75%, and ...
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This research was aimed to determine the best harvesting intensity for key and indicator species including Agropyron intermedium, Oryzopsis holciform, and Thymus fedtschenkoi in the cold semi steppe rangelands of Firoozkooh. Treatments consisted of different harvesting intensities of 25%, 50%, 75%, and control. In the first year, an area of one hectare was selected and fenced. From each of the above species, 40 average individuals were selected and each of the above treatments was applied on 10 individuals. The study individuals were distinguished by numbered signs and the harvesting was done manually by clipper. The data were analyzed in a split plot design in time and the means were compared using Duncan test. The results showed that the highest (24.59, 10.57, and 10.52 g) and the lowest (20.17, 9.91, and 5.78 g) yield were obtained at 25% and 75% harvesting intensities. According to the results of means comparison in different, the reduction of forage yield was affected by the harvesting intensity. The lowest (15.61, 8.59, 9.14 g) and highest (24.6, 10.8, 12.7 g) forage yield were recorded for the low-rain year (2008) and the wet year (2009), respectively. Therefore, a harvesting intensity of 25-50% could be recommended for the study species.
Taghi Mirhaji; Abbas Ali Sanadgol; Ali Ashraf Jafari
Volume 20, Issue 1 , June 2013, , Pages 11-22
Abstract
The evaluation of Festuca ovina L. with 16 accessions was carried out at Homand-Abesard Rangeland Research Station in order to select the best accession in terms of measured variables. The experiment started in 2003 and continued to 2007. After soil preparation, all accessions were planted on lines with ...
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The evaluation of Festuca ovina L. with 16 accessions was carried out at Homand-Abesard Rangeland Research Station in order to select the best accession in terms of measured variables. The experiment started in 2003 and continued to 2007. After soil preparation, all accessions were planted on lines with 13 m length with 75 cm intervals. The measured traits for plant selection were as follows: forage production, canopy cover, height, seed yield, number of flowering stems, leaf density, plant freshness and basal area. All data were statistically analyzed by SPSS annually and averages were compared using Duncan method. Results showed that there were significant differences among the measured traits and accessions (P≤0.05) in all studied years (2003-2007). In terms of seed yield and forage production, accession 10661 showed superiority to other accessions. This value was 1015 and 8.792 kg per hectare, respectively and the lowest amounts (307 and 6.133) were allocated to accession 10,679. Also, comparison of averages in different years showed that the highest amounts of pure seed in the fourth year were 1066 and 120.76 Kg per hectare, respectively. In addition, mean value comparison of canopy cover and basal area showed that accession 10671 with 2075 cm2 canopy cover and 731 cm2 basal area had superiority to other accessions recorded in 2006 and 2007. Among 8 studied traits in the nursery, 4 traits had effective and similar influence in accessions grouping. Therefore, similar accessions may be separated using fewer traits which are easily measurable and common in range management.
Seyed Taghi Mirhaji; Abbas Ali Sanadgol; Hasan Yeganeh
Volume 19, Issue 3 , December 2012, , Pages 522-534
Abstract
This research was conducted at Homand Absard research station, 70km east of Tehran, to study the establishment and survival of 10 accessions of Elytrigia libanoticus L. The experiment began in 2003 and continued until 2006. Of each accession, 25 individuals were cultivated on 13-meter lines at 50cm intervals. ...
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This research was conducted at Homand Absard research station, 70km east of Tehran, to study the establishment and survival of 10 accessions of Elytrigia libanoticus L. The experiment began in 2003 and continued until 2006. Of each accession, 25 individuals were cultivated on 13-meter lines at 50cm intervals. Cultivation lines were 75cm apart. Vigor, survival, forage and seed yield as well as growth parameters were recorded annually. The aim of the study was to determine the best accessions in view of survival and establishment. Obtained data in different years were entered in Excel and were analyzed with IRRISTAT software. Afterward, interaction effects of accessions and environment and additive main effects of the collected data were calculated using AMMI method in a randomized complete block design (RCBD). Mean comparisons were performed using Duncan's Multiple Range Test at 5% level. According to the results, there were significant differences among studied accessions at 1% level of probability during the study. Accession no. 10627 was identified as the best one while accessions 10624, 10628 and 10633 showed the lowest survival respectively
Sadegheh Zarekia; Ali Ehsani; Nilufar Zare; Taghi Mirhaji
Volume 18, Issue 3 , September 2011, , Pages 474-485
Abstract
Information on phenology of the range species is important to manage the plans of plant utilization, control of the livestock entry and exit, seed collection, and understanding of the nutritive value of plant species in different phenology stages. In this study, phenology of three important rangeland ...
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Information on phenology of the range species is important to manage the plans of plant utilization, control of the livestock entry and exit, seed collection, and understanding of the nutritive value of plant species in different phenology stages. In this study, phenology of three important rangeland species namely Astragalus chaborasicus, Poa sinaica and Stipa hohenackeriana was studied in Khoshkehrood saveh region. Vegetative and reproductive data of the mentioned species were recorded once a week for two years (2007 and 2008). Growing Degree Days (GDD) were determined using climate data (temperature and precipitation) collected from the nearest station to Saveh. The results showed that start and end of the phonological stages differed in two different years while GDD was almost same for phonological stages. In other words, phenological stages have constant temperature requirement which after obtaining the required temperature the emergence of the stages are observed and thus GDD is applied for prediction of phenological stages.
Taghi Mirhaji; Adel Jalili; Morteza Akbarzadeh
Volume 9, Issue 2 , September 2001, , Pages 729-742