Saeed Rashvand; Ali Ehsani; Hasan Yeganeh; Anvar Sour
Volume 21, Issue 4 , March 2015, , Pages 591-603
Abstract
Knowledge of the phenological stages of species constituting a plant community has a considerable importance in grazing management to achieve the goals of sustainable production. The study of plant phenology is critical for monitoring, management and conservation of ecosystems. In this research, ...
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Knowledge of the phenological stages of species constituting a plant community has a considerable importance in grazing management to achieve the goals of sustainable production. The study of plant phenology is critical for monitoring, management and conservation of ecosystems. In this research, the phenology of two shrub species including Artemisia aucheri and Thymus kotschyanus was investigated for four years during 2007 to 2010. For this purpose, 10 samples were selected from each species and the phenological data were recorded every 15 days and every 7 days in the vegetative and reproductive stages, respectively. Results showed that the start and end time of growth in different years in these two species differed under the influence of temperature and precipitation. The flowering stage of Thymus kotschyanus began in the first half of June, and the seeding stage started in the first half of July, continuing to the first half of August.The vegetative growth of Artemisia aucheri started from the second half of May, the flowering stage began in the late August and the seeding stage started from the last week of September, continuing for 2-3 weeks.
Zeinab Jafarian; Mansoureh Kargar; Jamshid Ghorbani
Volume 21, Issue 2 , August 2014, , Pages 234-236
Abstract
Spatial variability and heterogeneous geographical distribution of soil physical and chemical properties in rangeland ecosystems are affected by physical and biological factors including different managements, soil microclimate and topography, leading to the vegetation changes. Therefore, this research ...
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Spatial variability and heterogeneous geographical distribution of soil physical and chemical properties in rangeland ecosystems are affected by physical and biological factors including different managements, soil microclimate and topography, leading to the vegetation changes. Therefore, this research was aimed to study the spatial variability of production, density and canopy cover of Artemisia aucheri in the line with some soil properties variability in Vavsar rangelands of Kiasar. The sampling method was random-systematic. A total of five transects of 100m length were selected in the study area with a distance of 100m on which 10 plots of 2m2 were established with a distance of 10m. Soil samples were taken from a depth of 0-15 in each plot. In addition, production, density and canopy cover of Artemisia aucheri were measured in each plot. According to the results of geostatistical analysis in GS+ software, the percentage of clay and the density of Artemisia aucheri, showed the highest variation coefficients with the values of 82% and 53%, respectively. The variograms' amplitude varied from 196.2m for production to 910m for the percentage of moisture, lime, EC, and canopy cover. According to the results of cross validation, the models of lime percentage, density and production of Artemisia aucheri showed spatial correlation, and, consequently, had higher accuracy to be used in Kiriging interpolation.
Ali Ehsani; Mamak Ahmadian; Saeed Rashvand; Mohammad Ali Dehghani Tafti; Mostafa Zare
Volume 21, Issue 1 , June 2014, , Pages 13-23
Abstract
Study of the phenology of range key species is important to regulate and apply proper management for sustainable utilization of rangeland forage. In this study, the phenological stages of Artemisia aucheri were examined as a key species at three sites of different semi-steppe regions during 2007-2010. ...
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Study of the phenology of range key species is important to regulate and apply proper management for sustainable utilization of rangeland forage. In this study, the phenological stages of Artemisia aucheri were examined as a key species at three sites of different semi-steppe regions during 2007-2010. For this purpose, in each site, 10 individuals were selected and different phenological stages were recorded in 15-day and 7-day intervals for vegetative stage and reproductive stage, respectively. In addition, meteorological data including temperature and precipitation were recorded from the nearest synoptic station for each site. Results indicated that the occurrence of phenological phenomena of Artimisia aucheriwas more affected by temperature and precipitation indices of the growing season. According to the obtained results, the start and end of grazing were determined as early May to late October for Shirkooh (Yazd province), late May and early June to mid-July for Anjadan (Markazi province), and second half of May to mid September for Alamoot (Ghazvin province). Consequently, a complete understanding on the phenological stages of Ar. aucheri enables us to plan grazing management in order to determine the time of livestock entry into and exit from rangelands, optimal number of livestock for grazing and proper grazing systems.
Hosein Azarnivand; Yaser Ghasemiaryan; Reza Yari; Mohammad Ali Zare Chahouki; Esfandyar Jahantab
Volume 19, Issue 2 , September 2012, , Pages 297-305
Abstract
The aim of this study was to investigate allelopathic activity of aerial and underground organs of mountain sagebrush (Artemisia aucheri) on seed germination features, root length, shoot length and seed vigor of Festuca ovina.For this purpose, species of mountain sagebrush were collected from Taleghan ...
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The aim of this study was to investigate allelopathic activity of aerial and underground organs of mountain sagebrush (Artemisia aucheri) on seed germination features, root length, shoot length and seed vigor of Festuca ovina.For this purpose, species of mountain sagebrush were collected from Taleghan rangelands in Tehran Province and then were dried in direct sunlight and grinded.Powder derived from aerial and underground organs to the amounts of 3, 6 and 9 grams were separately mixed with 900 grams of sand in completely randomized blocks with four replications. In each pot, 10 seeds were planted at a depth of 2-3 cm. Germination percentage, germination velocity, seed vigor, root length, and shoot length were measured. Data analysis was performed using MSTATC software and mean comparisons were carried out using Duncan's test. Results showed that there were no significant differences among measured factors. Also, the shoot and root lengths showed significant differences at probability levels of 5% and 1%, respectively. According to the results, Artemisia aucheri caused a reduction of root length in Festuca ovina.
Hamid reza Mirdavudi; Abassali Sanadgol
Volume 16, Issue 2 , December 2009, , Pages 190-199
Abstract
In this research, first of all the key and important species as well as associated species of rangelands were recognized, then morphological and seasonal changes and preference value were determined on the selected species such as Artemisia aucheri, Kochia prostrata, Bromus tomentellus, Asperula glomerata ...
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In this research, first of all the key and important species as well as associated species of rangelands were recognized, then morphological and seasonal changes and preference value were determined on the selected species such as Artemisia aucheri, Kochia prostrata, Bromus tomentellus, Asperula glomerata and Buffonia cf.koelzii. In this research phonological stages of plants divided into 3 main stages including vegetative, flowering and seed maturity. Species preference values were studied with the method of time measurement. Effective factors on species palatability such as morphological characteristics, phonology, and chemical factors (Carbohydrates, Hemi cellulose, Protein…) of the species also were investigated. In the final step, data obtained in measurement time method were compared with environmental and morphological characteristics of the species as well as forage quality. The palatable species such as Bromus tomentellus, Asperula glomerata, Buffonia cf.koelzii and annual grasses were severally grazed in early time of the season. Rate of the grazing of, the species As. glomerata, Bu. cf.koelzii, Br. tomentellus and Ar.aucheri were 56, 59, 74 and 43 percent respectively. The laboratory analysis of forage quality also showed that there are positive correlation between moisture, protein and soluble sugar percentage with rate of forage use percentage. The regression equation showed that the amount of humidity, protein and soluble sugar with 56, 21 and 10 percent respectively shared in this model and high correlation of these factors showed their important role.
Ali beman Mirjalili; Ghasem ali Dianati Tilaki; Naser Baghestani
Volume 15, Issue 3 , January 2008, , Pages 295-303
Abstract
Five distance sampling techniques used to estimate density for Artemisia aucheri and Cornulaca monacantha species in this survey include: point center quarter, closest individual, nearest neighbor, random pairs and angle order methods. Sampling was conducted within 3 (40 m ×100 m) sampling areas ...
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Five distance sampling techniques used to estimate density for Artemisia aucheri and Cornulaca monacantha species in this survey include: point center quarter, closest individual, nearest neighbor, random pairs and angle order methods. Sampling was conducted within 3 (40 m ×100 m) sampling areas selected in TangLaybid. 30 points were selected equidistant apart along 10 randomly located 100-m transects for measurement of distance within each sampling area. Density obtained by each method was compared to the total count in a randomized complete design and Duncan’s test. Hopkines and Eberhardt indices were used to detect dispersion pattern of plants. The point center quarter method provided a reliable estimate of density for Cornulaca monacantha in the community with density of 0.38/ and a clumped distribution. The nearest neighbor method gave a reliable estimate of density for Artemisia aucheri in the communities with density of 1.8/ and 2.9/ and a tendency toward uniformity. Results showed that the point center quarter method can give reliable results in shrub communities with cover around 10% and a clumped pattern while the nearest neighbor method can give a reliable estimate in communities with cover between 16-20% and a uniform pattern.