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.
Ali Akbar Safdari; Zahra Mahmoodi; Hadi Memarian Khalilabad
Volume 15, Issue 3 , January 2008, Pages 304-319
Abstract
In the wind erosion process, there are three areas: detachment area, transport area and deposition area. The prevention of sediments movement in the detachment area is a basic task. Knowing origin of sediments of sand dunes, the recognition of the detachment regions is necessary. In order to origin study ...
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In the wind erosion process, there are three areas: detachment area, transport area and deposition area. The prevention of sediments movement in the detachment area is a basic task. Knowing origin of sediments of sand dunes, the recognition of the detachment regions is necessary. In order to origin study of eolian sediments in the Mokhtaran plateau, step-by-step method (Ekhtesasi-Ahmadi) was used. This study is done at tow stages: direction finding and location finding. To direction finding of taking sector, firstly by questionnaire completion, local winds information were gathered. Then satellite image (ETM+, 2002) and field investigations, the erg morphological map was provided. By studying of wind regime and wind rose drawing, the erosive winds were recognized. After recognition of taking sector (surrounding pediments of sand dunes), the location finding phase was started. In this stage by geomorphologic studying of taking sector and sampling into facieses, the mineralogical and morphoscopical studies of sand dunes and taking sector sediments were done. At least, the study shows that KUPH (schist and phyllit), Colored melonged and other sensitive formations in the east and southeast areas are basic sources of eolian sediments for Mokhtaran erg, which deposited by water erosion in the different parts of Mokhtaran plateau. In consequence of east and southeast erosive winds, these sediments are taken and deposited around of DAGH. These sediments were displaced so much time by winds that have different directions inside of the erg (north and northwest winds) and formed pyramid sand dunes. Thus in order to preventing of wind erosion, the initial sources i.e. KUPH formation and surrounding pediments must have in mind.
Hosein Arzani; Hasan Kaboli; Hamid reza Mirdavoodi; Mahdi Farahpoor
Volume 15, Issue 3 , January 2008, Pages 320-347
Abstract
Importance of permanent range assessment is advice, because of continuous change, ecological aspects and economy of rangelands. The wide area of rangelands and facilities limitation for regular monitoring cause the requirement of the remote sensing application. The objective of present study was investigation ...
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Importance of permanent range assessment is advice, because of continuous change, ecological aspects and economy of rangelands. The wide area of rangelands and facilities limitation for regular monitoring cause the requirement of the remote sensing application. The objective of present study was investigation on reliability of ETM+ data for vegetation estimation. The study was carried out in Markazi province for five years. Satellite data of same time of grand truth data was obtained for each year. Vegetation indices were calculated after radiometric and geometric correction of images. Canopy cover of annual species, herbaceous species, grasses, shrub and total cover in five sites during five years were measured. Measurements were carried out in 60 plots two square meters rectangular quadrates along four 400 meter parallel transects. Before processing of the information, 15 random selected quadrates were kept for test of equation. In other case all data of four years was applied to calculate equation between vegetation indices and ground data and data of fifth years was used for test of model. Considering small area of quadrates against 30*30 meter pixel and probability of error involved with coordinate measurement by GPS correlation between mean data of each transect and indices also was studied. The results obtained from equation were compared with actual cover data using student t-test. Most indices have significant correlation with cover data, however sometimes equation did not gave correct estimation of cover compared with actual data. This was happened for life form that did not make considerable percent of vegetation composition. Generally application of transect data and calculation of equation based on four years data to estimate of fifth years canopy cover was more suitable way of using satellites data. Certainly using satellite system with more bands and better resolution and doing soil background correlation in arid regions would give better results.
Hasan Ghelichhnia; Amr ali Shah moradi; Sadegheh Zare kia
Volume 15, Issue 3 , January 2008, Pages 348-359
Abstract
Providing information about range plant species, to be used as the main basis for managing rangelands, necessitates studying their ecological behavior and relationship with biotic and abiotic components of rangeland ecosystems. In rangeland ecology, this type of studies is considered as autecology of ...
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Providing information about range plant species, to be used as the main basis for managing rangelands, necessitates studying their ecological behavior and relationship with biotic and abiotic components of rangeland ecosystems. In rangeland ecology, this type of studies is considered as autecology of range plant species. This research was conducted to study autecology of two range plant species of Bromus tomentosus and Agropyron pectiniforme in Mazandaran Province. Site characteristics, including topography, climate, soil, and accompanied plant species were determined. For each of the two species, phenology, root system, and their way of presence in the vegetation cover of rangeland ecosystem were examined. The results showed that Agropyron pectiniforme grows in locations with an elevation range of 1200-3000 m above sea level. Soil texture of growing areas is loamy or silty-loam. Soil electrical conductivity (EC) is 0.45-0.94 ds/m, while soil pH is 7 to 7.86. Annual precipitation at its ecological habitats is 320-653 mm; and average annual temperature is 7.2-16.2 degree of centigrade. Canopy cover and frequency for this species were 7.22% and 36.6%, respectively. The root system of this range plant species is fibrous and distributes among soil particles down to the depth of 21 centimeter. Vegetative growth stage of this species starts in late March and ends in late April. Its flowering stage is from early May until early June, and seed ripening is in late June. The results of study on Bromus tomentosus showed that this plant grows in locations with an elevation range of 2300-3300 m above sea level. Soil texture of growing areas is loamy or silty-loam. Soil electrical conductivity (EC) is 0.40-0.72 ds/m while soil pH is 7.21 to 7.47. Annual precipitation at its ecological habitats is 510-653 mm; and average annual temperature is 7.2 degree of centigrade. Canopy cover and frequency for this species were 16.75% and 5.73%, respectively. The root system of this species is fibrous and distributes among soil particles down to the depth of 27 centimeter. Its vegetative growth stage starts in early April and ends in early May. Flowering stage of this range plant is from mid May until mid June, and seed ripening occurs in mid July. Ecological characteristics of these two range plant species need to be considered in management programs of related rangeland ecosystems.
Abbas Hente; Naser Ansari; Mohammad ali Zare chahuki
Volume 15, Issue 3 , January 2008, Pages 360-368
Abstract
This study was conducted to evaluate Atriplex canescens planting in Zarand-e-Saveh rangelands. For this purpose, a questionnaire about effects of Atriplex planting was prepared to be replied by randomly selected people whose herds use the rangelands. The questions were answered by 35 persons in ...
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This study was conducted to evaluate Atriplex canescens planting in Zarand-e-Saveh rangelands. For this purpose, a questionnaire about effects of Atriplex planting was prepared to be replied by randomly selected people whose herds use the rangelands. The questions were answered by 35 persons in 9 different villages. According to the answers, vegetation cover of the subject rangelands has been improved, the composition of herds is constant, and Atriplex plants are used only for grazing. Most of the herders believe that planting by Atriplex resulted in increase of production and quality of range forage, and consequently dairy products and meat production were boosted. Herders think that the fauna of the area has been changed. Conversely, some herders declare that grazing of Atriplex caused some gut damages, diarrhea and abortion in grazing animals. We believe that the reasons of these problems are early season grazing and also lack of diversity in plant composition (mono culturing).
Hamid reza Moradi; Khalag Mirnia; Shadi Lahur poor
Volume 15, Issue 3 , January 2008, Pages 369-378
Abstract
Rangelands have covered the majority of the continents and 43 percent of the all lands round the world cattle; so, they are very important in production and protection of water resource, soil and plant cover. The vast areas of rangelands of Kurdistan province are grazed by cattle. The main objective ...
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Rangelands have covered the majority of the continents and 43 percent of the all lands round the world cattle; so, they are very important in production and protection of water resource, soil and plant cover. The vast areas of rangelands of Kurdistan province are grazed by cattle. The main objective of this study was to determine the cattle grazing intensities effect on the soil of Charandoo rangelands which is located 23 km north of Sanandaj. Three different grazing site of: reference (light grazing) ere chosen as the study area. Forage production and physical soil factors such as bulk density, percent of porosity, water content and aggregate stability were measured by standard methods. Ten replications were used in this experiment. The statistical results show that cattle grazing have a significant effect on the plant cover and production. The soil bulk density increased significant with intensive grazing. The water content, percent of porosity and the proportion of the aggregate stability decreased as the result of intensive grazing. The final results indicate that cattle grazing may cause rather big changes on the physical properties of surface soil. As the project region enjoys suitable yearly rainfall, if the intensity of grazing is in a moderate level, the region will be ale to recompense and to make better tolerance the damages arisen from cattle trampling.
Mehrdad Mohammadnia; Chefuzia Ishak; Ahang Kowsar; raznani Abubakar
Volume 15, Issue 3 , January 2008, Pages 379-394
Abstract
Nitrate and ammonium are matters of concern as the two main inorganic nitrogenous species causing soil and water pollution. Nitrate, due to it's high mobility in soil and water systems, and due to it's involvement in gastric cancer in adults and methemoglobinemia in infants, is being more deleterious, ...
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Nitrate and ammonium are matters of concern as the two main inorganic nitrogenous species causing soil and water pollution. Nitrate, due to it's high mobility in soil and water systems, and due to it's involvement in gastric cancer in adults and methemoglobinemia in infants, is being more deleterious, as compared to ammonium. The main objective of this study was to determine the effects of soil and Eucalyptus camaldulensis Dehnh. rooting zone on the nitrate and ammonium removal from leaching water in saturated (laboratory) and semi-saturated soil columns (open field). The nitrate retardation factor (R), was 2.39 on the average, and nitrate dispersion coefficient (D) was equal to 7.57 and 10.18 cm2 hr-1 in control and planted saturated columns, respectively. Soil Kd was 0.35 in the nitrate batch adsorption isotherms. Planted columns, in both saturated and semi-saturated conditions, removed nitrate dramatically as compared to the controls. The removal coefficients were 30.18% and 84.71% for the saturated and semi-saturated columns, respectively. Consequently, based on the results one can say Eucalyptus camaldulensis Dehnh. is a suitable candidate as a nitrate phytoremediator.
Mohammad hosein Hadi Tavatory; Ahmad Akbarinia; Mahmood Khosravifard
Volume 15, Issue 3 , January 2008, Pages 395-402
Abstract
The performances of Shal sheep breed were investigated in sukling and grazing periods in 2006.with 61 lambs utilized ewes milk 105 days of ages. They had grazed the pastures of Alfalfa-Bromus and Atriplex , and aftermath of barley and wheat respectively. Daily gain of lambs were measured ...
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The performances of Shal sheep breed were investigated in sukling and grazing periods in 2006.with 61 lambs utilized ewes milk 105 days of ages. They had grazed the pastures of Alfalfa-Bromus and Atriplex , and aftermath of barley and wheat respectively. Daily gain of lambs were measured in each periods. Data were analyzed through factorial model and by completely random design. Results indicated that nutrition periods were significantly different (p<0.01) but the factors of sex of lamb, sex period and covariate of initial weight of lamb had not significant(p>0.05). Sukling period had the highest daily gain(182±6 gr/day) . Atriplex and aftermath of barley and wheat had the least performances (42±10 and 68±4 g/day, respectively).This result proves that Atriplex pasture like Alfalfa-Bromus pasture and aftermath of barley and wheat can supply maintenance requirement of lamb. It can be utilized as a source of roughage for grazing intermittence in semi-arid regions.
Mohammad ali Zare Chahoki; Marjan Shafizade
Volume 15, Issue 3 , January 2008, Pages 403-414
Abstract
The aim of this research was to study the relationships between presence of plant species and environmental factors in Chabeyki region of Yazd province. After delimitation of the study area, sampling was performed using randomized-systematic method. Within each type 5 parallel transects with 500 m length, ...
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The aim of this research was to study the relationships between presence of plant species and environmental factors in Chabeyki region of Yazd province. After delimitation of the study area, sampling was performed using randomized-systematic method. Within each type 5 parallel transects with 500 m length, each containing 50 quadrates (according to vegetation variations) were established. Quadrate size was determined for each vegetation type using the minimal area method. Soil samples were taken from 0-30 and 30-80 cm in starting and ending points of each transect. Measured soil properties included gravel, texture, available moisture, saturation moisture, organic matter, lime, gypsum, pH, electrical conductivity and soluble ions (Na+, K+, Mg2+, Ca2+, Cl-, , and ). Logistic regression technique was used to analyze the collected data. The results showed that the vegetation distribution is mainly related to soil characteristics such as gravel, saturation moisture, EC, pH, and lime. The presence of Cornulaca monocantha andCalligonum comosum has negative relation with saturation moisture and positive relation with gravel. Haloxylon aphyllum has also positive relation with pH. While, the presence of Seidlitzia rosmarinus has positive relation with Lime. EC has positive relation with the presence of Tamarix ramosissima.
Rahman Ebneabbsi; Hosein Maroofi
Volume 15, Issue 3 , January 2008, Pages 415-422
Abstract
For determining the nutritional value of Prangos ferulacea roughage in vegetative, flowering and seeding phenological stages, 30 samples were collected including five replication and two plants. After drying, using A.O.A.C method the attributes of dry matter, crude protein, crude fat, crude fiber, gross ...
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For determining the nutritional value of Prangos ferulacea roughage in vegetative, flowering and seeding phenological stages, 30 samples were collected including five replication and two plants. After drying, using A.O.A.C method the attributes of dry matter, crude protein, crude fat, crude fiber, gross energy, crude ash as well as the minerals Ca, P, Na, K, Mg, Cu, Mn, Zn and Fe were measured. The results showed significant differences (P<0.05) for both attributes in triple phonological stages: 15.2, 9.4 and 7.2 percent, and 15.8, 27.9 and 29.2 percent for crude protein and crude fiber, respectively. The macro elements minerals Ca, P, Na and Mg were measured 1.7, 0.17, 0.02, and 0.31 p.p.m. and the micro elements minerals Cu and were measured 8.0 and 32.6 p.p.m.. As a livestock forage, the mineral amounts, except P and Na, determined above the critical level in this species in Saral region.