List of Articles preferential flow

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  1 - Laboratory study of the influence of continuous and non-continuous macropore layers on solute transport in soil
  Farshid Taran علی اشرف صدرالدینی امیرحسین ناظمی
  One of the mechanisms of solute transport in soil is preferential flow or flow in macropores. In this study, to investigate the influence of macropore paths on solute transport, three soil bulks composed of 3% clay, 4.2% silt and 92.8% sand in a box with 200 cm length, More

  One of the mechanisms of solute transport in soil is preferential flow or flow in macropores. In this study, to investigate the influence of macropore paths on solute transport, three soil bulks composed of 3% clay, 4.2% silt and 92.8% sand in a box with 200 cm length, 100 cm width and 45 cm height were used. The first soil bulk was homogeneous (without macrpore path), the second one contained soil and layers of 5 cm thickness, composed of gravels with 2-4 mm diameter, from surface to bottom of the box (with continuous macropore layers), and the third one contained also contained soil and layers of same thickness and material, but the layers extended only to a depth of 35 cm (with non-continuous macropore layers). The transport of NaCl solution in these three soil bulks were experimented and then simulated using GeoStudio. In the soil bulk having continuous macropore layers, in comparison with the one with no macropore layer, the solute traveled the distance between the surface and the bottom in a shorter time (about 27%) and the peak concentrations were sooner observed (10-20 min). However, the non-continuous layers had no significant impact on the speed of solute transport. The GeoStudio software satisfactorily simulated the solute transport with the coefficient of determination more than 0.970 and the values of the root mean square error less than 0.25. Manuscript profile
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  2 - Transmission and Retention Status of the Contamination Index (Escherichia Coli) with Different Levels of Salinity in the Saturated Column
  Sahar Akhavan Soheila Ebrahimi Maryam Navabian Mahmoud Shabanpour Ali Mojtahedi Alireza Movahedi Naeini
  10.30495/jest.2022.28580.3736
  Background and Objectives: Escherichia coli is the most common fecal coliform in the cow manure that is considered as an indicator of groundwater contamination. In this regard, the present study was designed to investigate the preferential transmission and retention of More

  Background and Objectives: Escherichia coli is the most common fecal coliform in the cow manure that is considered as an indicator of groundwater contamination. In this regard, the present study was designed to investigate the preferential transmission and retention of Escherichia coli bacteria as an indicator of pollution in terms of using saline water. Material & Methodology: Laboratory studies were conducted in preferential flow system with synthetic m acro-pores with different diameter and salinity treatments under saturation flow in 2016. E. coli and chloride bio-tracer were used for detecting the effect of different water salinity levels. The wastewater samples were collected continuously during the transmission experiment at specific intervals. At the end of the experiment, three depths of soil from each column were sampled in two macro-porous and matrix areas. Then, the concentrations of bacteria and chloride were analyzed. Findings: The highest and the lowest concentration of E. coli in the collected drainage were observed in salinity of 1dS m-1 and 4dS m-1, respectively. At a depth of 5 cm, the bacterial retention rate was maximal and equal to 1.3 × 105 CFU-1. Discussion and Conclusion: The results showed that most of the treated bacteria were retained in the surface layers of the soil. Also, the amount of contaminants passing through the soil decreased with soil depth, so that the retention rate was decreased 10% per 5 cm increase in depth. In addition, the high concentration of bacteria exhausting from the soil columns treated with high salinity is due to the role of minerals such as salt in the transmission of bacteria. Therefore, water salinity can play an important role in reducing the pollution of groundwater resources. Manuscript profile