Yaser Ghasemi Aryan; Hossein Arzani; Esmaiel Filekesh; Reza Yari
Volume 20, Issue 1 , June 2013, Pages 1-10
Abstract
Determination of grazing capacity is considered as one of the most fundamental aspects of range management and understanding the effective factors on it is of utmost importance. Since the amount of forage production in a growth period is the basis for calculation of grazing capacity, in this research ...
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Determination of grazing capacity is considered as one of the most fundamental aspects of range management and understanding the effective factors on it is of utmost importance. Since the amount of forage production in a growth period is the basis for calculation of grazing capacity, in this research the estimation of production through the measurement of plant’s dimensions was investigated. For this purpose, the habitat of Artemisia siberi was determined and then 8 transects of 50 m length were established with 10 m intervals by random-systematic method. The height and diameter of 40 species of Artemisia siberi with different dimensions were recorded and the production of each species was clipped and weighted after drying. All data were analyzed by SPSS. Results showed that there was a significant linear correlation between production as a dependent variable and volume, canopy cover and height of Artemisia siberi as independent variables (R2= 0.88, 0.84, and 0.74, respectively) at 1% probability level. Finally, the relationship between production and volume was identified as the best linear relationship.
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 Ali Hossaini; Mansour Mesdaghi
Volume 20, Issue 1 , June 2013, Pages 23-37
Abstract
To find an accurate and rapid method of estimating herbage standing crop, clipping and weighing, double sampling, and comparative yield methods were compared in two vegetation types of grasslands and one cushion shrub land in Sar-Ali abad summer rangelands of Golestan province. In representative stands ...
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To find an accurate and rapid method of estimating herbage standing crop, clipping and weighing, double sampling, and comparative yield methods were compared in two vegetation types of grasslands and one cushion shrub land in Sar-Ali abad summer rangelands of Golestan province. In representative stands of each vegetation type, eighty 1-m2 plots were clipped and weighted. In double sampling, 16 plots were estimated and clipped. In comparative yield method, standard (reference) plots were used as the highest and the lowest yield were recorded for the reference plot 5 and reference plot 1, respectively. There was high correlation between estimated and clipped plots in double sampling. There was also high correlation between reference plots and their weights; therefore, the estimation of double sampling and the ranks of comparative yield method were corrected by using regression equations. There were no significant differences among 3 methods, but the time consumption of double sampling was better than the other methods. Given the widespread use of double sampling method in grasslands and shrub lands and also its high accuracy and precision, this method is recommended for the study area.
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).
Fazel Amiri; Hossein Arzani
Volume 20, Issue 1 , June 2013, Pages 50-71
Abstract
Range inventory is the recognition and evaluation of potential and actual production in order to take optimal utilization of this valuable natural resource. In this research, range suitability model for common use was determined by FAO (1991) and GIS with consideration of factors that affect the range ...
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Range inventory is the recognition and evaluation of potential and actual production in order to take optimal utilization of this valuable natural resource. In this research, range suitability model for common use was determined by FAO (1991) and GIS with consideration of factors that affect the range suitability for grazing. Sampling was performed in vegetation types randomly through the establishment of three transects of 200 m. Cover percentage and production were measured in quadrates of 1m2. Three criteria of available forage, water resources and erosion sensitivity were integrated to classify range lands suitability for livestock grazing. According to the results, there was no class of S1, however 694.36 hectares (9.7%) of rangeland was classified as class S2 and 5439.35 hectares (75.9%) was classified as class S3 with high limitation. In addition, 1025.81 hectares (14.3%) was not suitable for common grazing (class N). Most important limiting factors in soil erosion models were types of land use and land cover. Generally, there was no serious problem in terms of water resources in the study area. Only, in some parts of the watershed high distances from watering point and slope caused reduction in grazing suitability. Among rangeland characteristics cover and production were most important limiting factors in the study area.
Mehdi Jafari; Gholam Reza Zehtabian; Amir Houshang Ehsani
Volume 20, Issue 1 , June 2013, Pages 72-87
Abstract
Today, remote sensing data can provide the latest information for the study of land cover and land uses These images are of utmost importance due to the providing updated information, variety of forms and the possibility of processing for making land use maps. Determining the location of each land use ...
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Today, remote sensing data can provide the latest information for the study of land cover and land uses These images are of utmost importance due to the providing updated information, variety of forms and the possibility of processing for making land use maps. Determining the location of each land use together with land cover helps managers in making decisions. Also, the current status of the land cover can be studied by using land use maps at different levels. In order to evaluate the ability of multitemporal satellite data of TM and ETM + in land use classification and the effect of the thermal band on increasing the accuracy of the land use maps, Landsat TM digital data relating to the September 27, 1990 and Landsat ETM + digital data of 10 July 2002 from Kashan were analyzed. Initial studies were performed on images in terms of the presence of geometric errors. In order to prepare the images for digital processing, improved operation and image enhancement were applied on the images. Ground truth map was prepared in the same stage. Then, the supervised classification of satellite images with algorithms and different approaches including a variety of bands were tested and the accuracy of each of the methods and approaches were investigated. The results showed that the highest Kappa accuracy in both Landsat TM and ETM + with all the bands were 86.34 and 83.21, respectively. While the elimination of the thermal band decreases the accuracy to 82.46 and 79.93 % The results of this study showed that using thermal bonding caused an increase of 4 percent in Kappa accuracy, and the highest accuracy was occurred in the classes of clay plains, flood plains, mountains and puffy salt lands. Therefore, despite the lower spectral resolution, the use of thermal bonding is recommended in such studies.
Sedigheh Zarekia; Ali Ashrar Jafari; Ehsan Zandi Esfahan; Leila Fallah Hosseini
Volume 20, Issue 1 , June 2013, Pages 88-100
Abstract
To investigate the germination of perennial herbaceous Astragalus, six species in different accessions were selected to be studied in a randomized complete block design in which three treatments including control, scarification and chilling were applied for one week with three replications. The study ...
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To investigate the germination of perennial herbaceous Astragalus, six species in different accessions were selected to be studied in a randomized complete block design in which three treatments including control, scarification and chilling were applied for one week with three replications. The study was carried out in the laboratory of Gene Bank at RIFR. Germination percentage, germination rate, plumule and radicle lengths, vigor index and ratio of radicle to plumule length were measured. All data were analyzed and the studied species showed significant differences in terms of the mentioned germination parameters except radicle length and ratio of radicle to plumule while differences among treatments were significant for all traits except radicle length. Interaction effects of species*treatment were also significant except radicle length and vigor index. Maximum and minimum values of germination traits were recorded for A. vegetus and A. lilacinus, respectively and other species were classified as average. The values of germination traits in chilling treatment were less than that in control treatment and it can be concluded that the cultivation of these species in autumn and winter may cause unsuccessful establishment. According to the results, A. vegetus was identified as a suitable species for range improvement in terms of most germination traits.
Omid Karami; Seyed Mohammad Hosseini Nasr
Volume 20, Issue 1 , June 2013, Pages 101-114
Abstract
Determination of land capability for optimal use of land and prevention from land degradation due to improper use is an effective step towards sustainable development strategy. Due to the importance of the issue, in this study, ecological capability of Babolrood basin-Mazandaran for range management ...
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Determination of land capability for optimal use of land and prevention from land degradation due to improper use is an effective step towards sustainable development strategy. Due to the importance of the issue, in this study, ecological capability of Babolrood basin-Mazandaran for range management was evaluated using Analytical Hierarchy Process (AHP) and Geographic Information System (GIS). Thus, the hierarchy of evaluation process was created and the weights of criteria and indicators were computed using expert's judgments and indicators were mapped in GIS environment. In final step, ecological capability map of range management was generated using GIS-based Weighted Linear Combination (WLC) technique. Results showed that 78.94% of the study area had no capability and 1.21, 13.02, 6.7 and 0.13% of the study area had the class capability of first, second, third and fourth, respectively.
Fatemeh Salarian; Jamshid Ghorbani; Nosrat Allah Safaeian
Volume 20, Issue 1 , June 2013, Pages 115-129
Abstract
Grazing animals affect rangeland vegetation structure and function directly and indirectly. These effects can be assessed in exclosures. In this study, the vegetation composition and some vegetation indices (functional groups, biomass, species diversity and richness) were compared in an exclosure (livestock ...
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Grazing animals affect rangeland vegetation structure and function directly and indirectly. These effects can be assessed in exclosures. In this study, the vegetation composition and some vegetation indices (functional groups, biomass, species diversity and richness) were compared in an exclosure (livestock excluded for about 10 years) and grazed areas in Chahar Bagh rangeland in Golestan province. The percentage of canopy cover, stone and gravel, bare ground, litter and the biomass were estimated in quadrates of 1 m2. Results showed that there were 34 species common in both areas while 7 and 11 species were restricted to exclosure and grazed areas, respectively. Results of t-test showed that exclosure significantly increased the percentage of canopy cover of some desirable species such as Agropyron intermedium, A. trichophorum, Festuca ovina. Also, the percentage of canopy cover of hemicryptophyte, grasses, forbs, and perennials significantly increased in exclosure area. Moreover, Simpson diversity index and species number significantly increased in exclosure. The biomass of grasses and total biomass also significantly increased from grazed area to exclosure. According to the results, exclosure for less than ten years could cause some changes in vegetation of this rangeland.
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 ...
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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.
Mohammad Jangju; Fereidoon Mellati; Zohreh Atashgahi; Majid Vatanpour
Volume 20, Issue 1 , June 2013, Pages 145-160
Abstract
Autecology of three range plant species, i.e. Prangos latiloba Korov., Convolvulus commutatus Boiss, Stachys trinervis Aitch., was studied in the Northern Khorasan Province. These species provide forage for the grazing livestock in the rural rangelands, especially on the sheil formations. Geographical ...
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Autecology of three range plant species, i.e. Prangos latiloba Korov., Convolvulus commutatus Boiss, Stachys trinervis Aitch., was studied in the Northern Khorasan Province. These species provide forage for the grazing livestock in the rural rangelands, especially on the sheil formations. Geographical distribution was studied, in addition to topography, soil characteristics, and climate conditions of their natural habitats. Forage quality was assessed by measuring crude protein, ADF, NDF, dry matter, and ash. S. trinervis was growing in most of the rural rangelands, on the conglomerate, sandstone and shale formations, and under the arid and semiarid climate conditions. All species started their yearly growth at early April. For P. latiloba and C. commutatus, flowering and seed ripening stages similarly occurred at the early June and early August, respectively. For S. trinervis, phenological stages were overlapped, in which flowering, seed ripening and seed shedding were simultaneously found from the early May till early September. There was a sharp reduction in crude protein and increase in ADF and NDF factors, which led to significant reduction in the forage quality of all three species. The major limiting factors on geographic distribution of C. commutatus were: its high forage palatability and quality which had led to high effect of livestock grazing. For P. latiloba the main limiting factors were seed predation by pests and herbage harvesting by farmers. On the other hand, higher distribution of S. trinervis was due to having higher essences, lower palatability, overlap of phonological stages, and probably higher adaptation to climate and soil conditions.
Mohsen Padyab; Sadat Feyznia; Ardeshir Shafie
Volume 20, Issue 1 , June 2013, Pages 161-171
Abstract
Floodwater spreading is a simple method for extracting floods which in most parts of the country are usually lost. However, floods are usually rich in nutrient and can fertilize coarse-grained alluvial fan and floodplain sediments. Therefore, the aim of this research was the investigation of the effect ...
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Floodwater spreading is a simple method for extracting floods which in most parts of the country are usually lost. However, floods are usually rich in nutrient and can fertilize coarse-grained alluvial fan and floodplain sediments. Therefore, the aim of this research was the investigation of the effect of floodwater spreading on soil fertility in Gachsaran floodwater spreading station. For this purpose, for measuring N, K, P, EC, pH, organic carbon and soil texture, the soil and sediments were sampled in two depths of 0-15 and 15-30 centimetersfrom first and second strips of floodwater spreading and also from the representative area (area where floodwater spreading is not performed), and the samples were analyzed in the laboratory. According to the results, the amount of P, K, N, C and EC in two areas did not show meaningful difference but pH, percentage of clay and silt, decreased and increased, respectively in floodwater spreading and representative area and showed meaningful difference. It is concluded that there was no change in soil fertility due to floodwater spreading.
Ahmad Ahmadi; AmrAli Shahmoradi; Sedigheh Zarekia; Elahe Ahmadi; Saeedeh Nateghi
Volume 20, Issue 1 , June 2013, Pages 172-181
Abstract
In this research, Astragalus effusus was considered for autecological study in West Azarbaijan’s catchments. This palatable range species belongs to Papilionaceae. In this study, the ecological characteristics (climatic, topographic, edaphic), distribution in the catchments, phenology, root system, ...
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In this research, Astragalus effusus was considered for autecological study in West Azarbaijan’s catchments. This palatable range species belongs to Papilionaceae. In this study, the ecological characteristics (climatic, topographic, edaphic), distribution in the catchments, phenology, root system, and preference value of Astragalus effuses were investigated. The main part of the study was conducted in study sites of Poldasht (at the elevation of 900 m asl and mean annual rainfall of 120 mm), Shahidan valley (at the elevation of 1700 m asl and mean annual rainfall of 500 mm) and Salmas (at the elevation of 2000 m asl and mean annual rainfall of 338 mm) at different time intervals. The results showed that Astragalus effusus grew in all West Azarbaijan’s catchments from an elevation of approximately 800 to 3575 meters above sea level in all geographic aspects. It grew best on medium-textured soils, from sandy loams to clay loams. Some of the main companion species of Astragalus effusus were Onobrychis cornuta, Bromus tomentellus, Achillea millefolium, and Stachys schetschegleevii. In Salmas study site, the time of initial growth, vegetative growth, flowering, seed ripening and seed dispersion of this species were late March, late April, mid May, mid June and late July, respectively. Astragalus effusus was a tap-rooted species and its roots penetrated to the depths up to 2 meters in sandy loam soils of Salmas region. The geologic studies indicated that the main habitats of the Astragalus effusus were areas with lithologic characteristics of dark gray limestone and red marly limestone with shale in the upper part. This species had no toxic substances and was proper spring forage for livestock.
Mohsen Farshadfar; Ali Ashraf Jafari; Iraj Rezaie; Ezzat allah Farshadfar; Farzad Moradi; Hooshmand Safari
Volume 20, Issue 1 , June 2013, Pages 182-198
Abstract
Drought resistance of forage yield for 36 accessions of Festuca arundinacea were examined in randomized complete block design with three replications in both irrigated and rainfed environments. Significant variation (P<0.01) for forage dry matter yield was observed between the environments and genotypes. ...
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Drought resistance of forage yield for 36 accessions of Festuca arundinacea were examined in randomized complete block design with three replications in both irrigated and rainfed environments. Significant variation (P<0.01) for forage dry matter yield was observed between the environments and genotypes. The results of mean comparisons showed that accessions 6 (Isfehan), 7 (Isfehan), 15 (Tavankesh), 25 (Australia), 26 (America) and 31 (Australia) had higher values for forage dry matter yield, in both environment conditions. Drought resistance indices of genotypes were measured for forage dry matter yield of two environment conditions including sensitivity to stress index (SSI), tolerance (TOL), mean productivity (MP), drought tolerant index (DTI), harmonic mean (MH) and geometrical mean of productivity (GMP). Variance analysis of drought resistance indices showed that accessions had significant variation (P<0.01). The first and second components from principal component analysis were accounted for 61.5 and 37.7 percent of variation among accessions for drought resistance indices, respectively. The indices of MP, DTI, MH and GMP as well as forage dry matter yield of stress and non-stress environments had the greatest share in first component. Also, these indices showed significant and positive correlation with forage dry matter yield of stress and non-stress environments, and based on these indices, the accession 6 (Esfahan), 7 (Esfahan), 31 (Australia) and 26 (America), showed the most resistance to drought stress. Our results were confirmed by cluster analysis.
Zahra Pakzad; Mahmoud Raeini Sarjaz; Morteza Khodagholi
Volume 20, Issue 1 , June 2013, Pages 199-212
Abstract
To investigate the effect of climatic factors on distribution of Astragalus adscendens in rangelands of Isfahan province, 57 climatic variables with most importance in terms of ecology of this species were selected. Data were tested by factor analysis in SPSS 16. The maps of Isfahan climatic factors ...
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To investigate the effect of climatic factors on distribution of Astragalus adscendens in rangelands of Isfahan province, 57 climatic variables with most importance in terms of ecology of this species were selected. Data were tested by factor analysis in SPSS 16. The maps of Isfahan climatic factors in the factor analysis were drawn and integrated with the map of vegetation types and digital elevation map to identify the habitat of Astragalus adscendens. According to the results, the first three factors could explain 90.2% of total variance in selected variables as follows: temperature, precipitation, and radiation and wind, with 47.4, 30, and 12.8% of variance, respectively. The three climate factors were compared with the average of climate elements in the habitats of Astragalus adscendens and the areas without this species. Results showed that the areas with an altitude of 2400 m which have approximately 50% relative humidity, with more than 400 mm of rainfall per year and relative radiation are considered as the main habitat for Astragalus adscendens. The tolerance of this species to climatic factors is limited.
Mohammad Matinizadeh; Mahmoud Gudarzi
Volume 20, Issue 1 , June 2013, Pages 213-225
Abstract
Fire can severely affect vegetation and soil and prevent different cycles of ecosystems. Enzymes quantities are sensitive indices for soil quality, and the changes in their activity can affect the ability of ecosystem and alter nutrient uptake by plants. This investigation was carried out in Kordan rangeland ...
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Fire can severely affect vegetation and soil and prevent different cycles of ecosystems. Enzymes quantities are sensitive indices for soil quality, and the changes in their activity can affect the ability of ecosystem and alter nutrient uptake by plants. This investigation was carried out in Kordan rangeland in spring and autumn for two years. Soil was sampled from 0-20 cm depth. Three enzymes including acid phosphatase, alkaline phosphatase and dehydrogenase were assessed by reaction with substrate. Our results showed that the activities of all studied enzymes were significantly higher in soils in September at both areas. However, this difference was not high for alkaline phosphatase. Two years after fire, the activity of all studied enzymes was higher at control site. The reasons for this decrease may be due to the destruction of enzymatic system and increasing inorganic phosphate because of fire. Three years after fire, the activity of enzymes increased and for alkaline phosphatase and dehydrogenase was more than control site. These enzymes are considered as biological indices for soil microorganisms therefore, it can be expected that its increase indicates increasing microbial biomass in fire area.