Showing 27 results for بافت
O. Karami, A. Deljou, A. Mahmoudi Pour,
Volume 12, Issue 43 (4-2008)
Abstract
In vitro regeneration of two cultivars of carnation, namely, ‘Nelson’ and ‘Impulse’ was studied through direct somatic embryogenesis. Somatic embryos were formed directly on petal explants cultured on Murashige and Skoog (MS) medium containing different concentrations (0.2, 0.5, 1, 2, 4, 6 mg 1-1) of picloram. Maximum embryogenesis was obtained with 1 and 2 mg/l picloram. Globular shaped embryos were developed into cotyledonary-shaped embryos when they were transferred to the growth regulator-free media containing different concentrations (2, 4, 6, 8, and 10 %) of sucrose. Increasing sucrose concentrations in the culture media enhanced somatic embryos development. Cotyledonary somatic embryos developed plantlets when they were transferred to the half-strength MS culture medium containing 3% sucrose. Plantlets also continued to grow under greenhouse conditions.
O. Khademi, Y. Moustofi, Z. Zamani , M.r. Fatahi Moghaddam,
Volume 12, Issue 43 (4-2008)
Abstract
In this experiment the response of persimmon fruit, cv. Karaj, to astringency removal by ethanol and the effects of this treatment on some important fruit characteristics were investigated. Fruits were harvested at three different dates and at each date based on the previous results, and then modified treatments were applied. The best ethanol astringency removal treatment in this study was 10 ml of 38% ethanol per kg fruit for 48 hours. The period after ethanol treatments had no effect on the reduction of soluble tannin concentration, although it resulted in the reduction of flesh firmness and increased soluble pectin. Ethanol treatments and also temperature conditions reduced flesh firmness and increased ground color of fruits however, the effect of ethanol treatments was more than temperature conditions. Temperature conditions increased ethylene production, thus reducing the flesh firmness and increasing the ground color index of fruits. Ethanol treatments did not increase the ethylene production, and it seems that its effects on some characteristics are due to ethanol itself or factors other than ethylene.
A. Khazaei, M.r. Mosaddeghi, A.a. Mahboubi,
Volume 12, Issue 44 (7-2008)
Abstract
Soil physical and chemical properties, and test conditions might affect soil structural stability. In this study, the effects of test conditions as well as intrinsic soil properties on structural stability were investigated for selected soils from Hamedan Province. Mean weight diameter (MWD) and tensile strength (Y) of aggregates were determined by wet sieving method and indirect Brazilian test, respectively. The soil samples were pre-wetted slowly to matric suction of 200 kPa before the wet sieving. The pre-wetted samples were wet-sieved for 5, 10 and 15 min in order to simulate different hydro-mechanical stresses imposed on soil structure. Tensile strength of soil aggregates were also measured at air-dry and 500 kPa matric suction conditions. Short duration shaking (i.e. 5 min) could effectively discriminate the Hamedan soils in terms of structural stability due to their fairly low aggregate stabilities. The soil organic matter content had the highest impact on MWD followed by both clay and CaCO3 content. The same was true for the Y values i.e. OM played the highest role in mechanical strength of soil aggregates. The highest coefficient of determination (R2) was obtained between Y and the intrinsic soil properties for matric suction of 500 kPa. The organic matter content had an important role in water and mechanically stable soil aggregates. The results indicated that short-duration wet sieving (i.e. 5 min) and measurements of tensile strength at matric suction of 500 kPa could be recommended for aggregate stability assessment in Hamedan soils
H. Khoshghalb, K. Arzani, M. J. Malakouti, M. Barzegar,
Volume 12, Issue 45 (10-2008)
Abstract
Changes of the main sugars and organic acids content in Asian pear (Pyrus serotina Rehd.) Cultivars ‘KS’9 and ‘KS’13 grown in Tehran were studied from fruit set to maturity. The main sugars and organic acids content in fruits were determined 1 and 2 months before harvest, at the time of harvest and 1, 2 months after harvest time using High Performance Liquid Chromatography (HPLC). Fruits were stored at 2˚C and 80-85% relative humidity (RH). There were significant differences between cultivars and time of fruit harvest in terms of sugars and organic acids content. In both studied cultivars, fructose, glucose and sorbitol increased from the first fruit sampling to one month after harvest (1 to 9% FW) and then decreased. Sucrose content decreased from 2 months before harvest to 2 months after harvest time (3 to 0.75% FW). In both studied cultivars organic acids content increased at the time of pick-up and then decreased. The highest organic acids contents in the studied cultivars were malic and ascorbic acids (345 and 41.1mg 100g-1FW in ‘KS’9 and control, respectively). The relationship between low sugar and organic acid content in fruits showed the highest correlation (0.8 to 1) in both cultivars among low flesh firmness, low total soluble solid (TSS), low dry weight and high internal browning determined in this study. Results indicated that high content of sugars and organic acids in fruit led to delayed internal browning. Asian pears with a low ascorbic acid concentration are probably more susceptible to internal browning. High correlation was observed between high sugars content and high fruit colour.
A Farahanaki, Gh Mesbahi, H Askari,
Volume 12, Issue 46 (1-2009)
Abstract
Date fruit as a high calorie and valuable food source can be one of the main Iranian agricultural commodities for export, if properly processed and packed. The aim of this study was to process Kabkaab date variety from Routab (high moisture dates) to Tamar (known as dates or dry dates) using an industrial cabinet dryer. The Routab samples were dried using hot air at 56, 66, 76, 86 and 96 ˚C and changes in weight, moisture, pH, colour, texture and density of the dried samples were monitored. The results indicated that at 56 and 66 ˚C, drying rate was too low to be economic for an industrial process. At 86 and 96 ˚C the drying rate was high, although quality factors like colour was not acceptable. Therefore 76 ˚C is recommended as the best temperature for drying dates fruit. Moisture range of 24-27% (db) was the critical moisture level where a sharp decrease was observed in drying rate. Textural experiments of dates fruits with a wide range of moisture contents showed that above 30% moisture the hardness does not change with moisture level however, below 30% a small change in moisture can have a considerable impact on texture.
F Goodarzi,
Volume 12, Issue 46 (1-2009)
Abstract
To optimize the use of sulfur in drying of apricot, four following treatments including: sulfiting and drying, sulfiting- blanching and drying, blanching- sulfiting and drying, and finally sulfiting- drying to % 50 of initial moisture- blanching and finish drying were studied. The levels of sulfur addition were from 0 to 1500 ppm, SO2 and drying was carried out at 50 to 74 °C. The quality of dried apricots was judged by extent of browning development and hardness determination. A response surface statistical design was applied to evaluate the quality of slabs and to determine optimum drying conditions. The results showed that sulfite was the major factor in controlling dried apricot quality. At present of sulfur, the role of temperature can be neglected. The amount of used sulfite has no significant effect on drying time of apricots. Blanching reduced drying time of product significantly. By increasing the drying temperature, loss percentage of SO2 was reduced for all treatments. Blanching and then sulfiting, increased loss in residual sulfur of products significantly. Application of sulfiting– drying method, using 900 ppm of SO2 at 50 to 68 °C was found to be the best treatment because of production of slabs whit average hardness and color texture equal to 1.44 N/m2 and 0.07 Od respectively.
H. Shirani , E. Rizahbandi, H. Dashti, M.r. Mosaddeghi, M. Afyuni,
Volume 15, Issue 55 (4-2011)
Abstract
Organic matters are the most important factors that affect soil compactability and physical characteristics. In order to study the effect of pistachio waste on physical characteristics of two soils, a factorial experiment was conducted in a completely randomized design with three replications in a greenhouse. The treatments included pistachio waste at 4 levels (0, 3, 6 and 9 w/w %) and two types of soil texture (silty clay loam and sand).The results showed that the bulk density of sandy soil was decreased at high levels of waste application before compaction but had no significant effect on the bulk density of clay soil. The penetration resistance of both soil types was decreased by pistachio waste application. Soil water holding capacity increased and moisture curves shifted up for higher levels of organic matter application, while compaction curve reciprocally shifted into the lower levels by incorporation of wastes into the soils. At higher levels of organic matters, maximum bulk density was decreased and critical moisture was increased specially in fine texture soil. After compaction, the application of pistachio waste significantly reduced penetration resistance in silty clay loam soil relative to control but in sandy soil its effect on penetration resistance was only significant at maximum level (9 %).
E. Nabizadeh, H. Beigi Harchegani,
Volume 15, Issue 57 (10-2011)
Abstract
Selecting an appropriate particle size distribution (PSD) model for a particular soil may be important for a precise estimation of soil hydraulic properties. Various models have been proposed for describing soil PSDs. The objective of this study was to compare the quality of fitting of eight PSD models (Fredlund, Gompertz, van Genuchten, Jaki, Logarithmic, Exponential, Logarithmic-Exponential and Fractal) in 71 soil samples collected from Lordegan and Saman in Charmahal-va-Bakhtiari province, Iran. Coefficient of determination ( ) and Akaike’s information criterion ( ) were used to compare the goodness-of-fit of the models to the experimental data. Results showed that Fredlund model is best for describing PSD of silt loam, silty clay loam, silty clay and sandy loam soil textures. While Fractal, Exponential and Logarithmic-Exponential models produced the poorest-fit in silt loam, silty clay loam and silty clay, they had the best performance in sandy loam texture. The performance of Fredlund and Gompertz models improved with an increase in clay and silt content from 25 and 40 percentage, respectively. The performance of Fractal, Exponential and Logarithmic-Exponential models improved by increasing the sand content. Reverse correlation was observed between silt content and the performance of the Fractal model.
M. Ansari Azabadi , H.shirani, H. Dashti, A. Tajabadipur ,
Volume 15, Issue 57 (10-2011)
Abstract
Calcareous and gypsiferous soils are restricting factors for uptake of some plant nutrient elements and plant production. Most soils in Iran are calcareous and gypsiferous. Therefore, the aim of this study was the evaluation of calcium carbonate (Caco3) and gypsum effect on availability of some nutrients and corn growth. This study was conducted in a greenhouse at Vli-e-Asr University of Rafsanjan. Treatments were arranged in a factorial manner as a completely randomized design with three replications. Treatments were three levels of Caco3 (0, 20 and 40 g/100g soil), gypsum at three levels (0, 15 and 30 g/100g soil) and two soil textures (Sand and Silt clay loam). Results indicate that irrespective of soil texture, Caco3 application significantly decreased leaf area (by 80% and 15% for sand and silty clay loam texture, respectively), dry weight (by 80% and 15% respectively), plant height (regressed on Caco3 percentage by slopes -0.7 and -0.15 for sand and silty clay loam respectively), and shoot Fe (-9.67 and -11.3) and Zn (-0.24 and -1) uptake, but had no significant effect on shoot Cu uptake. In sandy soil, application of gypsum, significantly decreased leaf area (80%), dry weight (62%), and shoot Cu uptake (slope= -1.93), but had no significant effect on plant height and shoot Zn uptake. Gypsum application significantly reduced shoot Fe uptake (slope= -24.86) in fine textured soil, but it had no significant effect in coarse textured soil.
H. Khodaverdiloo, N. Hosseini Arablu,
Volume 18, Issue 67 (6-2014)
Abstract
Cation exchange capacity (CEC) is one of the important indices in soil fertility. Direct measurement of CEC is time consuming and expensive, especially in aridisols containing high amounts of carbonates and gypsum. Alternatively, CEC could be indirectly predicted through pedotransfer functions (PTF). The objective of this study was to predict CEC using class and continuous PTFs.A data set (n = 977) was classified according to the soil textural class and was used to derive the PTFs. Another independent set (n = 173) was used to test the reliability of the PTFs. The root mean of square error (RMSE), mean error (ME) and index of agreement (d) were applied to evaluate the PTFs. Within every textural class, we furthermore evaluated the relative improvement (RI) of the continuous PTFs over the corresponding class PTF. The continuous PTFs were more accurate than class PTFs for finer textural classes while the former showed higher reliability in coarser textural classes. With an increase in relative particle size, prediction bias of class PTFs decreased RMSE was 8.55 and 3.88 in clay and sandy loam textural classes, respectively. Consequently, according to the results obtained in this study, for the prediction of soil CEC, continuous PTFs are suggested to be used for silty loam and finer textural classes while for loam and coarser classes application of class PTFs is preferred.
N. Nourmahnad, H. Tabatabaei, A. R. Hoshmand, M. R. Nouri Emamzadei, Sh. Ghorbani Dashtaki,
Volume 18, Issue 68 (9-2014)
Abstract
Usually, dry soil readily absorbs water .However, not all soils display such characteristics. Some soils (hydrophobic soils) show resistance to wetting. Because of the importance of this subject and lack of research, we evaluated the effect of heating on water repellency and some of soil physical and chemical characteristics. So soil was combined with compost and heated at deferent temperatures, 100, 200, 300, 400 and 500 °C for 30 minutes in an oven or muffle furnace. The results showed that control treatment and heated soil at 300 °C had WDPT and MED 45 (s), 17% and 80 (s), 23% respectively. So, little water repellency was present prior to heating the soil. When soil was heated up to 300°C, intense water repellency resulted, but it was abruptly eliminated by increasing the heating. The soil texture was changed from loam to sandy loam at high temperatures (400 & 500 °C) and the sand percentage was increased. Organic matter decreased by increasing the temperature. Amount of pH decreased up to 200 °C and then increased at 500°C because of increasing ash in soils. Diminution of mineral and organic matter caused EC to decline in all the heated soils.
A. R. Vaezi, A. Vatani,
Volume 19, Issue 71 (6-2015)
Abstract
Rill erosion is the detachment and transport of soil particles by concentrated flow of runoff. It is the most common form of water erosion in the hill slopes. Rill erodibility is the rate at which soil particle is detached and transported by shear force of the concentrated flow. The study was conducted to determine the rill erodibility in different soil textures in Zanjan province using a rainfall simulator. To this end, samples of eight soil textures consisting of clay, clay loam, silty loam, sandy clay loam, sandy loam, loamy sand, and sandy were collected from land surface and transported to small plots (120 cm 100 cm) on a sloped uniform land (10%). The plots were exposed to five simulated rainfalls with a constant intensity of 60 mm h-1 for one hour. Based on the results, there was a significant difference among the soil textures in the rill erodibility (p< 0.01). Rill erodibility of the soils significantly correlated with mineral fraction (sand, clay, gravel) and exchangeable sodium percentage (ESP). With an increase in sand and gravel percentage, soil infiltration rate strongly increased and consequently production of the concentrated flow steadily decreased. Multiple regression analysis indicated that the rill erodibility in the soils was remarkably related to ESP (R2= 0.85, P< 0.01). Clay soil showed to have the highest rill erodibility among the soil textures due to higher exchangeable sodium percentage (ESP= 13).
H. Beigi Harchegani, G. Banitalebi, M. Ghobadinia,
Volume 21, Issue 1 (6-2017)
Abstract
Treated wastewater may influence soil structure, porosity and as a consequence, soil saturated hydraulic conductivity. This study aims to assess the effect of wastewater on saturated hydraulic conductivity; and to determine the suitable soil solids fractal dimension to incorporate into the pedotransfer function by Rawls et al (1993) for estimation of saturated hydraulic conductivity (Ks). Soil saturated hydraulic conductivity was measured by disc permeameter. Soil particle fractal dimension was calculated from linearized forms of mass- time, mass- diameter and mass- diameter as modified by Kravchenko- Zhang (1998) relations. Wastewater irrigation for 13 years increased the saturated hydraulic conductivity three times, from 7 mm/hour to 21 mm/hour, but longer application of wastewater did not further increase it. Rawls et al (1993) pedotransfer produced acceptable and relatively close saturated hydraulic conductivity values to that of disc permeameter when fractal dimension obtained from the linearized forms of mass- diameter and Kravchenko- Zhang relations were used. Therefore, Rawls et al (1993) pedotransfer was capable of reflecting the effect of wastewater application on soil saturated hydraulic conductivity.
A Fararooei, M. Noshadi, S. Amin Sichani,
Volume 22, Issue 1 (6-2018)
Abstract
PCBs are persistent organic pollutants which, due to high environmental hazards, must be traced, determined, and decomposed to reduce their risks. . To detect this material in the soil, the method of extraction and appropriate measuring conditions should be investigated. Two soil samples with two kg weight were selected with two different soil textures and the solutions of soil were made with the 1000 µg/ml aroclor 1254 mixture in a GC device. . Agilent GC-MS with stationary phase (CP 7477) was used to measure aroclor 1254. The analysis of variance and the test of the extraction mean of aroclor 1254 were compared in two soil textures. The results suggested that coarse texture soil (sandy loam) had a higher extract than the fine one (silty loam). The difference was statistically significant (P< 0.01). These findings suggested that the soil texture affected the extraction of aroclor from soil. In addition, four different levels of moisture (5%, 10%, 15% and 20%) produced in two soil textures and aroclor were measured. The highest level of extraction was obtained at 20% moisture, which was significantly higher than that in other levels (P< 0.01). The difference between the mean of extractions in the soil samples with 10% and 15% levels of moisture was non-significant (P> 0.05).
A. R. Vaezi, Kh. Sahandi, N. Sadeghian,
Volume 24, Issue 2 (7-2020)
Abstract
In semi-arid regions, soils are weakly aggregated and subjected to water erosion processes especially rill and interrill erosion. There is no information on the rate of these water erosion types in semi-arid soils located in the hillslopes. Therefore, this study was conducted to determine the soils susceptibility to these erosion types in semi-arid region. A laboratory experiment was done in eight soil textures using in a 0.6 m × 1 m flume a simulated rainfall with 50 mm.h-1 in intensity for 60 min. Rill and interrill erosion rate was measured using soil loss amount per flume area and rainfall duration. Based on the results, both rill and interrill erosion rate were significantly varied among the soils textures (P<0.001). Silt loam was the most susceptible soil to rill erosion (0.22 g m-2 sec-1) and interrill erosion (0.15 g m-2 sec-1), whereas sand didn’t appear any soil loss by these water erosion types. The compression of soil loss resulted by rill and interrill erosion among the soil tectures showed that rill erosion rate for sandy clay loam, silt loam, loam and sandy loam was 3.2, 1.4, 1.1 and 2.8 times higher than interrill erosion rate, respectively. These differences were statistically significant. Silt content was the major factor controlling soil loss difference in these soils. This study revealed that the study semi-arid soils having higher silt content appears also higher rill erosion rate than interrill erosion rate.
M. Jamali Jezeh, Mohammad Shayannejad, S. M Hejazi,
Volume 24, Issue 4 (11-2020)
Abstract
Water resources are limited in many areas of the world; sometimes, even these limited resources are negligently contaminated. One of the polluting factors of water is oil and its derivatives. Oil absorption using textiles is one of the common ways to separate oil from water. In this study, we used three types of textiles with different properties in order to make the filter. The experiments were performed using three different concentrations of 10, 20 and 30% oil. In this study, three types of BC, PET and PP textiles in the presence of horizontal and vertical drainages were investigated. The PET and PP textiles were made of nonwoven polyester and polypropylene fibers, respectively, and the BC textile was a two-component nonwoven textile of both polyester and polypropylene fibers that was used for the first time. Flow through the textiles was turbulent. Coefficients of flow were calculated using non-Darcy flow relations and the optimization method. The results showed that at low oil concentrations, the oil absorption had an inverse relation with the porosity and turbulent flow coefficients, but at higher concentrations, the effect of these agents was less; instead, the effect of the concentration and the intrinsic ability of the non-woven fibers was greater. The best performance was related to PP and PET with the horizontal drainage that had 95 and 91 absorption rates, respectively.
E. Karamian, M. Navabian, M.h. Biglouei, M. Rabiei,
Volume 28, Issue 1 (5-2024)
Abstract
Cultivation of rapeseed as the second crop requires drainage systems in most of the paddy fields of the Guilan province. Mole drainage, as a low-cost and shallow drainage method that is suitable for rice cultivation conditions and easier to implement than pipe drainage, can be a solution in the development of second-crop cultivation. The present study was conducted to evaluate the drainage of mole drainage and nitrogen fertilizer management on the quantity and quality of drainage at Guilan University. In this regard, an experiment was conducted under two treatments including drainage and nitrogen fertilizer (i.e. traditional mole drainage and sand-filled mole drainage), and 180 and 240 kg of nitrogen fertilizer per hectare in three replications. After each rainfall during the plant growth period, water samples were taken from the drains, and parameters of electrical conductivity, pH, total suspended solids, total phosphorus, turbidity, concentrations of ammonium, chloride, nitrite, nitrate, and phosphate were measured. Also, the outflow from the drains and the water table level were measured by piezometers during the rain and after that. The results of the mean comparison of pH and total suspended solids showed that most of them were obtained with 7.49 and 281.25 mg/liter, respectively, in the mole drain filled with sand and the traditional mole drainage and 180 fertilizer treatment. The highest mean of electrical conductivity and turbidity was observed as 651 micro mohs/cm in the traditional mole drainage and 240 fertilizer treatment and with 67.76 NTU in the traditional mole drainage and 180 fertilizer treatment. The statistical analysis showed that the effect of drainage treatment on the amounts of ammonium, nitrite, nitrate, phosphate, and total phosphorus was not significant. The outflow from the traditional mole drainage was 49% lower than the sand-filled mole drainage. The traditional and sand-filled mole drains were able to drain excess water with average reaction coefficients of 0.8 and 0.83 per day during the growth period, respectively. Considering the speed of water discharge, drain discharge, and the main non-significance of qualitative parameters among drainage treatments, mole drainage filled with sand is recommended for the development of rapeseed cultivation in paddy fields.
Sh. Amiri, B. Khalili,
Volume 29, Issue 1 (4-2025)
Abstract
Soils are continuously exposed to large amounts of engineered nanoparticles, particularly silver nanoparticles (AgNPs), which can affect soil microbial activities and nitrogen cycling. The hypotheses of the present study were: (i) vegetation types would differ in their responses to Ag types and concentrations, (ii) these responses would be linked to changes in soil protein and amino acid concentrations, and (iii) combined plant root systems alongside Ag types and concentrations would have offsetting effects on soil protein and amino acid concentrations. A greenhouse experiment was conducted to test these hypotheses using a factorial arrangement of treatments within a randomized block design. Two soil types with loamy sand and sandy loam textures were collected from agricultural fields in Isfahan, specifically from the Badroud (33◦ 44′ 50" N, 51◦ 57′ 55" E) and Femi (33◦ 42′ 17" N, 51◦ 59′58" E) regions. The treatments included: 1) soil types (loamy sand and sandy loam), 2) root systems (non-planted, wheat, and safflower), 3) Ag types (no Ag added, AgNPs, and AgNO3), and 4) Ag concentrations (50 and 100 ppm). The plants were harvested 110 days after sowing, with soil samples collected from both the root zone and non-planted soil, after which the concentrations of protein and amino acids were measured. In the Badroud soil, protein concentration significantly decreased (p < 0.05) with increasing depth. Although depth changes did not show a significant difference in protein concentration in the soil under wheat cultivation, increasing depth resulted in a significant decrease (p < 0.05) in protein concentration in the soil under safflower cultivation. In the Fami soil, the addition of silver nitrate led to a significant (p < 0.05) increase in protein concentration, despite the fact that the addition of silver nanoparticles had no significant (p < 0.05) effect on soil protein concentration. In the Badroud soil, the highest concentration of soil amino acids was observed in the silver nitrate treatment, while the silver nanoparticle treatment did not significantly affect soil amino acid concentrations (p < 0.05). However, applying silver treatments at both tested concentrations resulted in a significant increase (p < 0.05) in soil amino acid levels. Overall, the effects of nanoparticles varied depending on the measured parameters (protein or amino acid), soil texture, and type of cultivation. Further studies are needed to determine the mechanisms by which AgNPs and AgNO3 affect the soil nitrogen cycle in the presence of plants at different soil depths.
Mohammad Saeid Hosseini, Aliashraf Amirinejad,
Volume 29, Issue 4 (12-2025)
Abstract
Improvement of soil characteristics is one of the important issues in agricultural and engineering sciences. To investigate the effect of silica nanoparticles on the soil's mechanical and physical properties, a factorial experiment was conducted based on a completely randomized design with three replications. The factors included silica nanoparticles at three levels (0%, 0.5%, and 1% by weight) and two soil types with loam and clay loam textures. The results of the shear strength test showed that the addition of nanosilica increased the internal friction angle and particle adhesion in both loam and clay loam textures, but the liquid limit and plasticity index decreased in both soils. In the consolidation test, the compressibility coefficient in loam decreased from 0.38 to 0.21 and in clay loam from 0.42 to 0.23, while the swelling coefficient in loam decreased from 0.13 to 0.07 and in clay loam from 0.18 to 0.08. Overall, the results showed a significant effect of nanosilica particles on improving soil mechanical strength, especially in clay loam with higher clay content and specific surface area. Therefore, it can be concluded that the use of silica nanoparticles is an effective method for stabilizing problematic soils.
Dr. Ali Reza Vaezi, Saeideh Akbari, Fereshteh Haghshenas,
Volume 30, Issue 1 (3-2026)
Abstract
Splash erosion is the initial stage of soil erosion by water, which can be significantly influenced by soil properties. The rate of this type of soil erosion in drylands of semi-arid regions is high due to sparse vegetation cover, particularly during the early stages of plant growth. This study was conducted to investigate the soil properties determining splash erosion in semi-arid drylands. Soil aggregates with a diameter of 6 to 8 mm were taken from the soil surface (0-30 cm depth) in thirty dryland farms at three replications. Soil aggregates were purred into splash bowls and exposed to simulated rainfalls with an intensity of 60 mm h-1 for 30 minutes. Different soil properties were determined in ninety soil samples. Based on the results, the highest splash erosion occurred in clay loam (0.0021 gm⁻²s⁻¹), while the lowest value was in loamy sand texture (0.0008 gm⁻²s⁻¹). Splash erosion was significantly affected by grain size distribution; so that positive correlations were found with silt (r= 0.43), clay (r= 0.44), and dispersible clay (r= 0.47), whereas negative correlations existed with sand (r= -0.46) and gravel (r= -0.53). Furthermore, splash erosion was considerably influenced by organic matter (r= -0.23), calcium carbonate (r= -0.22), bulk density (r= -0.60), aggregate stability (r= -0.44), and hydraulic conductivity (r= -0.44). This study revealed that the drylands with fine-textured soils and having a lower amount of organic matter as well as calcium carbonate, have a higher susceptibility to splash erosion in semi-arid regions.
