Sayed Naeim Emami; Hamzeh-ali Shirmardi
Volume 29, Issue 4 , January 2023, , Pages 579-595
Abstract
The establishment and growth of vegetation on marly lands is usually difficult because of mineralogical properties of marls especially clay minerals aggregation as impermeable fraction in these rocks and sediments. This research aims to systematically investigate relatively densely grown plant species ...
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The establishment and growth of vegetation on marly lands is usually difficult because of mineralogical properties of marls especially clay minerals aggregation as impermeable fraction in these rocks and sediments. This research aims to systematically investigate relatively densely grown plant species and determine their habitat needs as well as their protective role in the soils resulting from the erosion of the Gurpi marly belonging to the Cretaceous period with a thickness of more than 100 meters in two regions as Vastegan and Dorahan areas in Borujen Township, Chaharmahal & Bakhtiari province. For this purpose, 65 marl soil samples were taken and physical and chemical tests were performed on 31 samples. Botanical surveys performed using repeated field visits and plat made up on the 180 plots and plant samples were identified after moving to plant museum (Herbarium) of agricultural and natural resources research and education center. In general, more than 400 plant species growing in the region and on different formations. A collection of rangeland species Astragalusbrachycalyx-Daphnemucronata- Cirsiumbracteosum with a density of more than 50% can be present in the lands resulting from the erosion of neutral marl lands(PH =7-8) with moderate lime amount and without Na+ and Cl- presence can established and go through its growth stages. In addition, a collection and colony of rangeland species with the combination of Astragalus susianus-Daphne mucronata-Amygdalus elaeagnifolia) can be established in alkaline marl (pH>8) with high amount of lime fraction and cl- and should be presented as a biological solution to control the erosion of the soils affected by the erosion of alkaline marls.
Peyman Madanchi; reza Bayat; Kaka shahedi
Volume 24, Issue 4 , January 2018, , Pages 757-767
Abstract
Soil is one of the most important resources in each country and if it is not protected it will be lost due to erosion and gradually loses its fertility. Soil loss will fill the stream channels, reservoirs and cause serious damages like decreasing crop production per unit area. This ...
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Soil is one of the most important resources in each country and if it is not protected it will be lost due to erosion and gradually loses its fertility. Soil loss will fill the stream channels, reservoirs and cause serious damages like decreasing crop production per unit area. This study was conducted to evaluate the effects of watershed management practices including mechanical and biological measures to reduce erosion and sedimentation in Daremorid watershed in Kerman province. In this study, MPSIAC model parameters such as surface runoff factor, land cover factor, land use factor, current state of erosion factor, channel erosion factor, and sediment behind small dams were used. The results showed that the sediment yield was estimated to be 36653.38 tons per year which is more than the sediment yield calculated in preliminary studies in this watershed (51378.46 tons per year). Based on statistical analysis using SPSS software, the results revealed that there were significant differences between sedimentation and erosion, particularly in each of the parcels in the watershed.
Sadat Feiznia; Hasan Ahmadi; Soheila Youneszadeh Jalili; Mohammad Ali Fatahi ardakani; Marzeiyeh Abbasi
Volume 19, Issue 2 , September 2012, , Pages 244-263
Abstract
Differences in particle size through downstream is a proper tool to understand evolution steps and river channel morphological changes, including sediment transport, channel migration context, the risk of floods and human activities. The present study investigated sediment deposits in upper rangelands ...
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Differences in particle size through downstream is a proper tool to understand evolution steps and river channel morphological changes, including sediment transport, channel migration context, the risk of floods and human activities. The present study investigated sediment deposits in upper rangelands of Tehran- Qazvin highway located in Khur-Sefidarak Basin, Tehran Province. Two main channels with Gravelly- sand bed as the main drainage channels were studied. The aim of this study was to investigate changes in particle size based upon sedimentology and its correlation with textural parameters including sorting, skewness, and kurtosis and calculating the approximate volume of sediments behind dams. These parameters were analyzed by sampling 66 samples from upstream to the downstream side of the Khor-Sefidarak channels. All natural factors (secondary branches and sediment sources) and non-natural factors (such as small dams) were effective in tissue changes on this system and the results indicated the continuity of sediment along the channels due to regular gradient of channel bed. Sediment particles through these two channels had a medium sorting. Sorting decreased toward downstream, because of facing secondary branches and increment of shared formation number and totally increased diversity in sediments. Results of bed sediment volume showed that the amounts of bed load sediment through Khor and Sefidarak branches were 271.6 and 246.3 cubic meters per year, respectively.
Marzieh Abassi; Sadaat Feiznia; Hamid reza Abassi; Uones Kazemi; Ahmad Gharanjik
Volume 18, Issue 3 , September 2011, , Pages 441-451
Abstract
Source identification of sand dunes is of particular importance in projects of wind erosion control. In this study, the map of geomorphology and inventory map of sand dunes were prepared for five regions of Baluchestan under wind erosion using aerial photos, satellite images and Arc-View ...
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Source identification of sand dunes is of particular importance in projects of wind erosion control. In this study, the map of geomorphology and inventory map of sand dunes were prepared for five regions of Baluchestan under wind erosion using aerial photos, satellite images and Arc-View and Arc-GIS soft wares. Then, 28 samples were collected based on the form of sand dunes and geomorphological facies. The samples were analyzed for Granulometry, morphoscopy and mineralogy in the laboratory. Granulometric analysis was performed using dry–sieving technique and the curves and statistics were drawn and calculated using Gradistat software. The morphoscopic and mineralogic investigation were performed using binocular microscope. Granulometric analyses show that the sediments are well sorted, having better sorting than fluvial sediments, with standard deviation of less than 0.5. Morphoscopic analyses mostly show the effect of Aeolian transport on the grains. Mineralogical studies show that the most abundant particles in the sediments are rock fragments consisting of limestone, quartzite and granodiorite (%84), and the rest are minerals such as quartz, feldspat and calcite. About 94.5 percent of the particles have been transported in saltation. The results of differentiation of sediments according to sedimentary processes indicate that about %71.43 of sediments are transported and deposited by Aeolian processes, %21.42 by fluvial processes and %7.15 by overlapping of Aeolian and fluvial processes.
Aziz Arsham; Ali mohammad Akhund ali; Abdolkarim Behnia
Volume 16, Issue 4 , January 2010, , Pages 445-455
Abstract
Antecedent soil moisture is one of runoff and sedimentation crucial factors affected by parameters such as soil properties, topographic-, climatic-, and coverage circumstances etc. The work aimed at determining effects of soil properties and rainfall on runoff and sediment load at various antecedent ...
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Antecedent soil moisture is one of runoff and sedimentation crucial factors affected by parameters such as soil properties, topographic-, climatic-, and coverage circumstances etc. The work aimed at determining effects of soil properties and rainfall on runoff and sediment load at various antecedent moisture levels. Heavy, medium and light textured field soils were selected, exposed to a constantly intensified 80mm/hr rainfall under air-dried, air-dried to field capacity point, field capacity point and nearly saturated conditions, and two slopes of 5 and 15%. Recording runoff and sedimentation values every 2-5 min; populated values were calculated within 10, 20 and 30 min. intervals. All experiments were carried out with simulated rainfall technique in a 1×1×0.1m flume. Treatments showed most significant differences within first 10min. decreased with increasing rainfall duration. Maximum runoff coefficients increased as 2-5 folds as minimum ones with all durations. When moisture increased to field capacity point, light, medium and heavy textured soils had the lowest to the highest values of runoff coefficient, respectively. Under nearly saturated condition, increasing runoff trend decelerated with heavy textured soils and decreased to a lesser extent as compared to medium textured samples. Also, sedimentation process was consistent with runoff fluctuations. Medium textured soils showed a significant level of sedimentation under nearly saturated conditions. Runoff coefficients were unnoticeably different with 5 and 15% slopes; however, a more significant sedimentation increase occurred with 15% slope.