Naser Baghestani Meybodi; Hosein Arzani; Mohammad Taghi Zare; Jalal Abdollahi
Volume 11, Issue 2 , August 2019, , Pages 137-162
Ali mohebbi; Farhang Ghasriani; Mina Bayat; Gholamhosein Rahmani; qasem khodahami; ghasemali abarsaji; Mohamad ali Dehghani Tafti; Farideh Saghafi Khadem
Volume 24, Issue 3 , October 2017, , Pages 471-477
Mohsen Sharafatmand
Volume 23, Issue 3 , January 2017, , Pages 627-635
Abstract
There are various methods to measure the utilization of grasses that each of these methods has its own advantages and disadvantages. The use of utilization gauge for grasses and grass-like species is one of these methods. This research was aimed to investigate the efficiency of utilization gauge in determining ...
Read More
There are various methods to measure the utilization of grasses that each of these methods has its own advantages and disadvantages. The use of utilization gauge for grasses and grass-like species is one of these methods. This research was aimed to investigate the efficiency of utilization gauge in determining the utilization rate of native grasses in Iran. Thus, the utilization rate of Agropyron cristatum and Stipa barbata was measured by utilization gauge method, and the conformity of results with the weight ratio method (control) was assessed by linear regression. Since the utilization scales are prerequisite to the use of utilization gauge, which currently do not exist in our country, first these scales were developed. For this purpose, 30 plant individuals were sampled, of which 25 individuals were used to provide utilization scales and five individuals were used to evaluate the conformity of the two methods. According to the results, the two methods showed good conformity, so that the utilization gauge could be used to estimate the utilization of grasses. Since this method is rapid, non-destructive, and cheap, the use of utilization gauge is recommended to estimate the utilization rate of native grasses.
Mohsen Sherafatmandrad; Gholamali Heshmati; Mohammadrahim Forouzeh; Hosein Badripour
Volume 21, Issue 3 , December 2014, , Pages 447-454
Abstract
Measurements of production and utilization of key range plant species are of utmost important tools for making range management decisions specially for stocking rate determination. A study was conducted to examine the relationships of production and utilization of Agropyron cristatum and Stipa barbata, ...
Read More
Measurements of production and utilization of key range plant species are of utmost important tools for making range management decisions specially for stocking rate determination. A study was conducted to examine the relationships of production and utilization of Agropyron cristatum and Stipa barbata, as key grasses in Chaharbagh region of Golestan province, with some dimensional parameters. For this purpose, plants height, basal diameter and canopy diameter and their dry weights were measured. Primarily, correlation matrices and Pearson correlation coefficient were used to assess the relationships of these three dimensional variables with production. The three variables were then evaluated for predicting production by using best subset and stepwise regression approaches. Utilization was assessed based on percentage of height removed in relation to percentage weight removed. Results showed that basal and canopy diameters could usefully predict the production of the two grasses. Finally, because of subjectivity of canopy diameter measurements and its weak role in explaining production variations, just basal diameter was considered in models, having linear relationship with production and the coefficient of determinations were calculated to be 72.4 and 71 for A. cristatum and S. barbata, respectively. Therefore, dimension analysis is an appropriate approach to estimate the production and utilization of range key grasses.
Jalal Abdollahi; Hossein Naderi; Mohammad Reza Mirjalili; Monireh sadat Tabatabaeezadeh
Volume 20, Issue 1 , June 2013, , Pages 130-144
Abstract
Understanding the behavior and action of plant species and their ecological relationships with environmental variables is essential as an important part of the information required in range improvement, rehabilitation and proper utilization of rangelands. In this research, the effects of environmental ...
Read More
Understanding the behavior and action of plant species and their ecological relationships with environmental variables is essential as an important part of the information required in range improvement, rehabilitation and proper utilization of rangelands. In this research, the effects of environmental factors on quantitative growth characteristics of Stipa barbata were investigated by ordination method in rangelands of Nodoushan –Yazd. For this purpose, twenty five sites were identified using the vegetation map and field visits, and in each reference area 30 plots were established along 3 transects of 500 m with random-systematic sampling. Inside the plots, a list of existing species, canopy cover, number of species and production were recorded. Three soil samples were taken from 0–30 cm depth. Soil samples were pooled together to obtain a composite sample. Clay, silt, sand, organic matter, lime, pH, electrical conductivity, sodium, calcium and magnesium were measured. Topographic features such as slope, altitude and aspect, were also recorded, and the type of formation was determined using geological maps. The relationships between growth parameters of stipa barbata and environmental factors were determined using Canonical Correspondence Analysis (CCA) method. Results showed that there were significant correlations among canopy cover, density and yield with soil factors. According to the results, among soil factors, soil texture, pH, SAR, Ca+2/Na+, calcium carbonate (T.N.V) and gravel had the most influence on canopy cover, density and yield. The effect of topography variables on growth characteristics was not significant. A significant relationship was found between growth characteristics of S. barbata and the type of geological formation.
Ebrahim Farahani; Amrali Shahmoradi; Sadegheh Zarekia; Farhad Azhir
Volume 15, Issue 1 , January 2008, , Pages 86-94
Abstract
Studying the behavior and the way a plant species functions, and investigating on its relationship with biotic and abiotic components of its habitat is considered as autecology of that plant species. This type of studies provide valuable information which is necessary for rangeland ecosystems management. ...
Read More
Studying the behavior and the way a plant species functions, and investigating on its relationship with biotic and abiotic components of its habitat is considered as autecology of that plant species. This type of studies provide valuable information which is necessary for rangeland ecosystems management. This research was conducted to study the autecology of Stipa barbata. In this study, some topographic, climatic, and edaphic characteristics of the rangeland ecosystem, in which the plant species grows, were determined. Names of accompanied plant species in the ecosystem were listed. Based on physiognomy, this plant is the dominant species in most of its habitats. Its canopy cover, density, and frequency are 4.5%, 32750 plant/ha, and 82.5%, respectively. Phenology, root system, and the way of presence of Stipa barbata in the ecosystem were evaluated. The results showed that the habitats of this species are located in elevation range of 890 to 3300 meters above sea level while the major habitats are include elevation range of 1100 to 2800 meters above sea level. The species grows on slopes of 0.5 to 100%. Mean annual precipitation are 221 mm and 485 mm in Eshtehard and Zidasht Taleghan, respectively. Mean annual temperature are 15.5 and 24.5 degree Centigrade in Firoozkooh and Rood Shoor, respectively. The habitats for this plant species include very shallow to deep soils. Vegetative growth starts in early March and ends in early April. Its flowering stage is from mid May to mid June. Seed ripening stage is from late June until mid July. The plant has a shallow fibrous root system.