A Vaezi, H Bahrami, H Sadeghi, M Mahdian,
Volume 13, Issue 49 (10-2009)
Abstract
Proper evaluation of soil erodibility factor is very important in assessment of soil erosion. In this study, soil erodibility factor (K) was assessed in a zone, 900 km2 in area in Hashtrood, located in a semi-arid region in north west of Iran. Soil erodibility factor was measured at the unit plots under natural rainfall events in 36 different lands in the study area from March 2005 to March 2007. Results indicated that the measured soil erodibility factor K is on average 8.77 times lower than the nomograph-based values in the study area. To achieve a new nomograph, correlation between measured soil erodibility and soil physicochemical properties was studied. Based on the results, soil erodibility factor negatively correlated with coarse sand, clay, organic matter, lime, aggregate stability and permeability, while its correlation with very fine sand and silt was positive. Results of principal component analysis of soil properties and multi-regression analysis showed that the soil erodibility factor is significantly (R2 = 0.92, P < 0.001) related to soil permeability, aggregate stability, lime and coarse sand. A new nomograph with a R2 of 92% was developed based on these properties to easily estimate soil erodibility factor in the study area. The soil erodibility factor can be reliably estimated using the nomograph in all regions with the soil and rain properties similar to those in the study area.
S. M. A. Zomorodian, A. Soleymani,
Volume 21, Issue 1 (6-2017)
Abstract
Erosion is one of the main factors of destruction of hydraulic structures. Therefore, soil improvement is necessary to improve soil quality and reduce soil erosion. Due to the adverse effects of substances such as lime and ash and also the increasing usage of nanotechnology in various branches of engineering sciences, using nanoparticles as new additives is an efficient way. In this study, to investigate the effect of nanosilica additive on soil, erosion function apparatus (EFA) is used. Samples containing nanosilica with 0, 1, 1.5, 2 and 4 percent (w/w) of dry soil were compacted in the standard compaction mold. They were tested in a close flume and with variable discharges. Erodibility parameters showed that by addition of 1.5% nanosilica to the dry soil, erodibility decreased by 92% as compared with untreated soil. The optimal amount of nanosilica was chosen as 1.5%. The results showed that samples compacted with the optimum moisture content causes the least erodibility. Scanning Electron Microscope (SEM) tests results showed that by addition of nanosilica to the dry soil, soil structure becomes more dense which reduces the risk of erosion.
Z. Feizi, A. Ranjbar Fordoee, A.r. Shakeri,
Volume 27, Issue 2 (9-2023)
Abstract
Maintaining soil structure and stability is essential, especially in arid and semi-arid regions with poor soil structural stability. Destruction of soil and its crust can cause wind erosion and desertification. The objective of this study was to investigate the effect of using hydrogel nanocomposite mulch on the stabilization of sand surfaces. A wind tunnel test was used to evaluate the erodibility of samples treated with different amounts of hydrogel nanocomposite. The compressive strength of the samples was measured by a manual penetrometer. The prepared nanocomposites were examined using scanning electron microscopy (FE-SEM), infrared spectroscopy (FTIR), and X-ray diffraction (XRD) images. The results of the wind tunnel showed that the addition of hydrogel nanocomposite to the samples improved the soil erosion rate by 100% at a speed of 15 m/s compared to the control sample. Bonding between sand particles by spraying hydrogel nanocomposites improves the erodibility of sand. Measurement of mechanical strength of treated samples after 30 days showed that the resistance of the crust increased with increasing the amount of nanocellulose in the composite, which can be expressed due to the increased surface area of the nanoparticle and the possibility of further bonding of the nanocomposite polymer bed with sand particles. While the crust diameter showed no significant difference with increasing concentration and the sample treated with nanocomposites containing 3% nanoparticles was thicker compared to other samples.
