Saeed Rashvand
Volume 22, Issue 1 , June 2015, , Pages 143-157
Abstract
Studying the phenology of range species is important in determining the time for livestock entry to and exit from rangeland. This research was conducted in semi-steppe rangelands of Alamoot, Qazvin for four years during 2007 to 2010. Among 82 species, six key species were selected of which four species ...
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Studying the phenology of range species is important in determining the time for livestock entry to and exit from rangeland. This research was conducted in semi-steppe rangelands of Alamoot, Qazvin for four years during 2007 to 2010. Among 82 species, six key species were selected of which four species were grass (Dactylis glomerata, Bromus tomentellus, Festuca ovina, and Agropyron intermedium) and two were shrub (Thymus kotschyanus and Artemisia aucheri). From each species, 10 individuals were selected to study their phenology. Vegetative stage of key grasses started from the first half of May and was completed by the end of month. Flowering stage started from the last week of May and continued to the first half of June for 15-18 days, and seeding stage started from the second half of June and lasted for 10-15 days. The vegetative stage of Thymus kotschyanus started from the first half of May and was completed after 30-35 days. Flowering stage started from the second decade of June and was completed after 15-17 days. Seeding stage started from the third decade of June and lasted for 10-13 days. The vegetative stage of Artemisia aucheri began from the second half of May and was completed by the first decade of July, continuing for 45-55 days. Flowering stage started from the second decade of July and continued to the second decade of September. Seeding stage started from the early second decade of September and lasted to the end of October. According to the results of soil analysis, soil moisture is very low in the end of May, suitable for livestock entry to the rangeland. Our results clearly showed that early June was the time for livestock entry to the rangeland, and the second half of August was determined as the time for livestock exit from rangeland.
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.
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.
Saeed Rashvand; Jamal Mosafaee; Mohammad Darvish; Ammar Rafee emam
Volume 20, Issue 1 , June 2013, , Pages 38-49
Abstract
Vegetation and biological production is one of the most important factors in providing human needs and sustainability of ecosystems and living organisms. Otherwise, the natural lands will become desert and non-residential regions. Deterioration of vegetation is one of the major causes of desertification. ...
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Vegetation and biological production is one of the most important factors in providing human needs and sustainability of ecosystems and living organisms. Otherwise, the natural lands will become desert and non-residential regions. Deterioration of vegetation is one of the major causes of desertification. In the current research, the assessment of desertification in terms of deterioration of vegetation was performed using the FAO and UNEP method in Rood shoor, Qazvin. For this purpose, the digital map of potential vulnerability was generated from geometric mean of three indices including moisture regime, temperature regime, soil depth and texture. For digital mapping of perennial to annual plants ratio, the map of vegetation types (31 even vegetation types) was prepared and in each type four plots were established in order to record the production and canopy cover percentage. Finally, the final map of potential desertification was generated and classified by the integration of digital maps of potential vulnerability and perennial to annual plants ratio. From the total area of the sub basin which is equal to 2275000 hectares, agricultural lands and non rangelands (1034745 ha) which covers 46 % of the sub basin were not assessed in the classification. The rest was classified as follows: 31685 ha (low), 1191394 ha (medium) and 17176 ha (high).
Saeid Rashvand; Hoshmand Safari; Parvaneh Ashouri sanjabi
Volume 19, Issue 2 , September 2012, , Pages 355-369
Abstract
In this study, sustainability of forage production in some rangeland species of mountainous rangelands of Alamut Qazvin was investigated. These mountainous rangelands are located in the highlands of North-Eastern city of Qazvin as a part of south basin of central Alborz Mountains. The rainfall of these ...
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In this study, sustainability of forage production in some rangeland species of mountainous rangelands of Alamut Qazvin was investigated. These mountainous rangelands are located in the highlands of North-Eastern city of Qazvin as a part of south basin of central Alborz Mountains. The rainfall of these natural environments is 400 mm per year. Long dry season is considered as the main characteristics of the natural environments of these ecosystems. Production per hectare of 24 species was studied during four years. Combined analysis of variance for dry forage production (kg/ha) showed significant differences (p>0.01) among species and the years. According to the results of mean comparisons (Duncan’s multiple test) and cluster analysis (Ward method), Eryngium billardieri, Cousinia esfandiari, Artemisia aucheri, Verbascum speciosum, Agropyron intermedium, and Cirsium haussknechtii had higher forage production. Interaction effect of species * year was significant at 1% probability level and sustainability parameters were calculated based upon average forage production. Parameters of CVi, S2di and R2 had similar trends in introduction of sustainable species and most of them showed low forage production based upon these parameters. Parameters of Bi, W2i and S2i also showed the same trend in expression of sustainability and on the basis of these three parameters, an average forage production was recorded for most of sustainable species. In general, Cousinia esfandiari and Artemisia aucheri showed appropriate production sustainability based upon most sustainability parameters. Agropyron intermedium and Cirsium haussknechtii were not sensitive to adverse conditions while Verbascum speciosum and Eryngium billardieri were sensitive to adverse conditions. Therefore, Agropyron intermedium and Artemisia aucheri could be introduced for range improvement programs.