JWSS - Journal of Water and Soil Science

Landscapes are considered as a series of different land units with a size, shape and location arrangement that are permanently under the influence of natural events and human activities. Understanding the dynamics and heterogeneity of landscapes and environmental changes is of great importance. In order to quantitatively analyze and interpret the factors affecting the changes in the environment and terrain diversity, diversity indices were used to analyze the ecosystem. In this study, the relationships between soils evolution and geomorphic surfaces were investigated by applying pedodiversity indices in a part of a semi-arid region of Chaharmahal-Va-Bakhtiyari Province. In the studied area, three orders were recognized: Mollisols, Inceptisols, and Entisols. The results showed that soil evolution in the studied area was mostly influenced by topography, parent material and the underground water level; that is, in the higher lands, the lowest evolution was observed while in the plain ones, the soil of the higher evolution observed. In addition, the effect of geomorphic surfaces were obvious. Pedodiversity indices increased under the decrease of the hierarchy levels. In addition, the obtained equations revealed the nonlinear relationships in the area of geomorphic surfaces. The positive and nonlinear relationship between pedodiversity indices confirmed the nonlinear dynamic system in the studied soils.

To study the behaviour of phosphorus (P) sorption in the agricultural soils of Khoy region and the effect of long-term cultural management with the application of poultry manure on the P sorption parameters, bath experiments were carried out with 16 soil samples (8 cultivated and 8 virgin soils) and 9 initial P concentrations from 0 to 30 mg L-1 in 0.01M CaCl₂ as a background solution. After equilibrium, the remaining amount of P in solution was measured and the experimental sorption data were fitted to the Langmuir (R²=0.93-0.99) and Freundlich (R²=0.87-0.99) models. The results showed that P sorption was increased with enhancing the initial P concentration, eventually reaching the steady-state plateau. Based on the coefficient of determination (R²) and the standard error of estimate (SE), both isotherms models, Langmuir and Freundlich, showed a relatively good fit to the experimental data. The maximum mono layer sorption of Langmuir (qmax) varied from 233 to 486 and from 340 to540 mg kg^-1, and the energy parameter of Langmuir (KL) ranged from 0.12 to 0.50 and from 0.22 to 0.71 for the cultivated and virgin soils, respectively. Freundlich sorption capacity (KF) and intensity (n) parameters showed the same trends and KF varied from 36.4 to 123 and 59.3 to 145.2; also n varied from 1.18 to 1.50 and 1.47 to 1.71 in the cultivated and virgin soils, respectively. Consequently, all sorption parameters and the buffering indices showed a decreasing trend in the cultivated soils, as compared to the corresponding virgin soils and the cultural and fertilization management; especially, the application of the poultry manure in this region reduced phosphorus sorption by soil and then increased phosphorus availability to plants. Hence, less fertilizer would be needed to maintain a favourable P concentration in the soil solution for the optimum plant growth.

Despite the great importance of potassium applied as a fertilizer in the orange orchards, no information is currently available regarding the rate of potassium release from rhizosphere and the bulk soils of such trees. The objectives of this study were to investigate the weathering of micaceous minerals and their non-exchangeable K release and also, to examine the status of different forms of K in the rhizosphere and bulk soils of orange orchards with different ages in Darab, Fars Province. Samples were, accordingly, taken from the rhizosphere and bulk soils of orange orchards with the ages of 5, 10 and 20 years; also, virgin soils (control) were obtained from three soil depths including 0–30, 30–60, and 60–100 cm. Water soluble, exchangeable and nonexchangeable K, and the clay mineralogy of the soils were determined. The results demonstrated that the concentration of soluble and exchangeable K in the cultivated soils was less than that in the control soil and that the concentration of nonexchangeable K in the soils of 20-year-old orchards was less, than that in other soils. Soluble and exchangeable K values decreased with depth in all soils. Clay mineralogy investigation also showed that the quantity of illite decreased and that of smectite and illite-smectite increased as the age of orange trees was raised. With increasing the age of orange trees and root development, more potassium could be taken up from soil and more changes occurred in the soil minerals. In order to avoid a very high decline in the reserved K in the soils under orange trees, particularly in the orchards with older trees, K fertilization has to be taken more seriously based on the soil testing results.

Use of the curve gradient of the Soil Water Retention Curves (SWRC) in the inflection point (S Index) is one of the main indices for assessing the soil quality for management objectives in agricultural and garden lands. In this study Anneling Simulated – artificial neural network (SA-ANN) hybrid algorithm was used to identify the most effective soil features on estimation of S Index in Jiroft plain. For this purpose, 350 disturbed and undisturbed soils samples were collected from the agricultural and garden lands and then some physical and chemical soil properties including Sand, Silt, Clay percent, Electrical Conductivity at saturation, Bulk Density, total porosity, Organic Mater, and percent of equal Calcium Carbonate were measured. Moreover, the soil moisture amount was determined within the suctions of 0, 10, 30, 50, 100, 300, 500, 1000, 1500 KP using pressure plate. Then, the determinant features influencing the modeling of S Index were derived using SA-ANN hybrid algorithm. The results indicated that modeling precision increased by reducing the input variables. According to the sensitivity analysis, the Bulk Density had the highest sensitivity coefficient (sensitivity coefficient=0.5) and was identified as the determinant feature for modeling the S Index. So, since increasing the number of features does not necessarily increase the accuracy of modeling, reducing input features is due to cost reduction and time-consuming research.

Furrow irrigation is the most common method of surface irrigation. However, the accurate estimation of the soil water infiltration equation is the most important challenge for evaluating this method of irrigation. In this study, a fast and simple method that is named soil intake families and presented by USDA-NRCS (RSIF), evaluated for estimation of the Kostiakove-lewis infiltration equation parameters based on soil information. Also, this method was developed based on irrigation condition and considering soil characteristics (D-RSIF). Two treatments including constant and variable inflow discharge were tested with 4 repetitions and different irrigation phases including advance, storage and recession were simulated by developed Zero-Inertia model using RSIF and D-RSIF methods. The results showed that using the zero- inertial model, the difference between simulated advance times and simulated runoff were significant at 5% level for D-RSIF and RSIF methods. For variable inflow discharge, the error of estimating runoff volume was 10%, 6%, 12% and 41% for RSIF, D-RSIF, multilevel calibration and two-point methods respectively. Also, the irrigation scheduling error, based on soil physics characteristics (RSIF) was 14% that means consuming water more than required.

In general, rivers are one of the best and most accessible water resources at the disposal of mankind.  So, given the effect of the force of water and changes on the  flow patterns and consequently, on river morphology changes, the analysis of the flow in the river is important and necessary to organize projects, flood control and water supply structures downstream. In this study, by using numerical models CCHE2D hydraulic conditions Dimeh River Bridge between Oregon Bridge Sudjan was investigated. CCHE Model is a mathematical model capable of simulating the flow patterns and sediment transport in rivers and canals laboratory network. The numerical model in 1998, based on the calculations by the National Centre for Water Science and Engineering, University of Mississippi (NCCHE), was developed and has been applied in many research projects related to water engineering. At the outset, the input data required model provides and numerical model was implemented. In the next step, the results of the model were calibrated and validated using field data measurements; eventually, they were extracted and their model results were compared; it was confirmed that CCHE model could still simulate the flow pattern.

River discharge is among the influential factors on the operation of water resources systems and the design of hydraulic structures, such as dams; so the study of it is of great importance. Several effective factors on this non-linear phenomenon have caused the discharge to be assumed as being accidental. According to the basics the chaos theory, the seemingly random and chaotic systems have regular patterns that are predictable. In this research, by using methods of phase space mapping, correlation dimension, largest Lyapunov exponent and Fourier spectrum power, a period covering 43 years of Zayandehrud River discharge (1971-2013) was evaluated and analyzed based on the chaos theory. According to the results, the non-integer value of the correlation dimension for Eskandari and Ghale Shahrokh stations (3.34 and 3.6) showed that there was a chaotic behavior in the upstream of Zayandehrud-Dam Reservoir. On the other hand, in the Tanzimi-Dam station, the correlation dimension curve was ascending with respect to the embedding dimension, showing that the studied time-series in the downstream of Zayandehrud-Dam Reservoir was random. The slope of the Lyapunov exponent curve for Eskandari, Ghale Shahrokh and Tanzimi-Dam stations was 0.0104, 0.017 and 0.0192, respectively, and the prediction horizon in the chaotic stations was 96 and 59 days. The non-periodical feature of time series was studied by using the Fourier spectrum power. The wide bandwidth, besides other indices, showed that river discharge in the upstream stations of Zayandehrud Reservoir was chaotic.

River discharge is among the influential factors on the operation of water resources systems and the design of hydraulic structures, such as dams; so the study of it is of great importance. Several effective factors on this non-linear phenomenon have caused the discharge to be assumed as being accidental. According to the basics the chaos theory, the seemingly random and chaotic systems have regular patterns that are predictable. In this research, by using methods of phase space mapping, correlation dimension, largest Liapunov exponent and Fourier spectrum power, a period covering 43 years of Zayandehrud River discharge (1971-2013) was evaluated and analyzed based on the chaos theory. According to the results, the non-integer value of the correlation dimension for Eskandari and Ghale Shahrokh stations (3.34 and 3.6) showed that there was a chaotic behavior in the upstream of Zayandehrud-Dam Reservoir. On the other hand, in the Tanzimi-Dam station, the correlation dimension curve was ascending with respect to the embedding dimension, showing that the studied time-series in the downstream of Zayandehrud-Dam Reservoir was random. The slope of the Lyapunov exponent curve for Eskandari, Ghale Shahrokh and Tanzimi-Dam stations was 0.0104, 0.017 and 0.0192, respectively, and the prediction horizon in the chaotic stations was 96 and 59 days. The non-periodical feature of time series was studied by using the Fourier spectrum power. The wide bandwidth, besides other indices, showed that river discharge in the upstream stations of Zayandehrud Reservoir was chaotic.

After Hamidieh Diversion Dam near the city of Hamidieh, Karkheh River is divided into two streams known as Hufel and Nissan. At the lower flow rates, Nissan makes up a greater share than Hufel due to the steeper slope of the former. This study attempted to construct a hydraulic structure to appropriately divide water flow in Hufel. In a laboratory experiment, a flume with a 90-degree bend was used at Islamic Azad University of Ahvaz. Various experiments were conducted at different widths and heights. Furthermore, this model was simulated through CCHE2D, the results of which were compared against those of physical and mathematical models. The results indicated that the weir height increased the deviation flow percentage to the Hufel stream due to rising water level. Moreover, the deviation flow percentage to Hufel was declined as the weir width was increased due to falling water level. At Hufel, the installation of rectangular weir in different dimensions yielded the minimum of 34.3% and the maximum of 61.5% increase in the flow rate. In the normal mode without any weirs installed, however, there would be an increase in the flow rate, as compared to the mode where a weir has been installed. This can be associated with the flow controlled by the weir. On average, the deviation flow rate was increased by 2.8% in the weir mode and 7.7% in the weir-less one. An increase in the Froude number from 0.21 to 0.38 led to a lower average deviation flow rate by 19.3%. Moreover, the results of the simulation through CCHE2D were demonstrated to be largely similar to those of physical model experiments. However, an increase in the Froude number did not lead to a decline in the deviation flow rate (i.e. it remained constant). This trend was inconsistent with the results of the physical model.

Identifying the rainfall characteristics and understanding the rainfall-related processes is one of the key factors in the scientific management of water resources. Selection of the design storm is the first step in the estimation of the design flood. Determining temporal rainfall patterns is very important as one of the design rainfall properties in flood estimation and the design of drainage systems. This study was concerned with the pattern of rainfall depth during its occurrence at the Dez dam station. In order to plot Huff curves in the Dez dam station, the recorded data of the rain gauge was used. For this purpose, all 280 storms from 1972 to 2016 in different seasons were classified into the five distinct classes including i) 0-2 hours, ii) 2-6 hours, iii) 6-12 hours, iv) 12-24 hours, and v) more than 24 hours. Furthermore, for each class and in each of the seasons, the Huff curves were plotted using all storms information single class. Moreover, for the considered station, all recorded events were considered in a single class and the general Huff curve was plotted using the probability of 50%. In general, the highest number of storms in the Dez dam (about 32.9%) was grouped in the second quartile. However, it was about 55, 48.5 and 50.4 percent in the case of short storms (0-2 hours) for spring, autumn and winter, respectively. In contrast, low percentages were obtained for the rainfalls having long durations. The Logistic equation was extracted for all Huff curves. These curves would be useful in efficient water resources management. The value of the correlation coefficient between the amounts obtained from the Logistic model and the corresponding values extracted from the curves was more than 0.99, which was significant in 1 percent.

Soil is one of the most important natural resources of countries in which erosion occurs. In this research, the effect of soil characteristics on the amount of erosion at the suborder level was studied. For this purpose, 77 soil samples (0-30 cm) were prepared and the parameters were determined in the laboratory. The semi-variograms of soil parameters and their spatial distribution maps were prepared with GS⁺ and GIS, respectively. The study area was divided into work units by combining land use and geology maps and water erosion was estimated at each unit by the EPM method. By drilling profiles in different parts of study area, soil suborders were determined by Soil Taxonomy and the average values of parameters in each suborder was estimated. The principle components analysis (PCA) was then used for data analysis. The results showed that three parameters of silt, organic carbon and electrical conductivity could account for 30.384% as the first main component; clay, sand and vegetation could explain 11.189% as the second main component; and slope and height covered 15.330% as the third main component; in total, 63.805% percent of erosion variation could be justified by three main components. The lowest and highest amounts of erosion (69.12 and 343.57 m³/km², respectively) were estimated in Xeralfs and Fluvents suborders. The erosion class of suborders at the study area was determined to be “few” and “medium”.

A ‘spillway’ is a structure used to provide the controlled release of flood water from upstream into downstream area of a dam. As an important component of every dam, a spillway should be constructed strongly, reliably and efficiently to be used at any moment. Labyrinth and stepped spillways are presented as appropriate modifications to those spillways hardly capable of managing the maximum potential discharge. Owing to their nonlinear crests for a given width, labyrinth and stepped spillways have a larger discharge rate than linear- crest spillways at an identical height. Compared to other energy dissipaters, the combination of stepped and labyrinth spillways is known as a very strong energy dissipater. In the following part, the combination of these two structures and their dimensional change for increasing the water- energy dissipation are addressed. To conduct this study, an experimental flume with a 90- degree bend in the Islamic Azad University of Ahwaz was used. In total, 90 experiments were conducted on three different labyrinth- shape stepped spillway models with two different lengths, three different widths, and five different discharges. Analysis of the results showed a greater energy loss reduction in triangular rather than rectangular or trapezoidal labyrinth- shape stepped spillways. In addition, energy loss was greater in labyrinth spillways with two cycles than those with one cycle. Energy loss was increased by raising the Froude number from 0.05 to 0.1; in contrast, energy loss was decreased with increasing the Froude number from 0.1 to 1.0, which was due to the submergence of steps, a decrease in the roughness of steps and an increase in the intensity of aeration.

The production of compost and vermicompost from manure and different organic residues and also, their enrichment with some fertilizers and other treatments have been extensively investigated. However, no study has yet been conducted on the enrichment of composted and vermicomposted manure with clay minerals. This research was, therefore, carried out to investigate the selected properties of phlogopite enriched manure during the composting process with and without earthworm activity. The experiment was conducted in plastic containers with the lid under an average temperature of 27.5°C and the humidity of 42.5% using a factorial arrangement in a completely randomized design with 3 replications. Factors included levels of phlogopite addition (0%, 20% and 40% by weight), with or without the earthworm Eisenia fetida for different time periods of 1.5, 3, 4.5 and 6 months. At the end of the experiment, the total of organic carbon, nitrogen, potassium, magnesium, and iron, as well as the contraction the available magnesium, potassium and iron, was determined. The results showed that the percent of organic carbon was decreased while the total nitrogen, the total and available potassium, iron and magnesium were increased with time. The results also indicated that a significant percentage of the total content of the elements in all treatments without phlogopite was available. However, in treatments containing phlogopite, the amount of the available elements was increased slowly with time. This was Due to the weathering of phlogopite mineral and the decomposition of manure. In general, it seems that the enrichment of composted and vermicomposed manure with phlogopite can guarantee the supply of nutrients such as potassium, iron and magnesium in a longer period, as compared with the ordinary composts.

Erosion under the conveying pipeline affected by river flow at the cross to rivers is one the important reasons for breaking the pipelines that can lead to leakage. While the mechanism of erosion under the conveying pipeline in steady flow has been studied by many researchers, studies have shown the importance of scouring research in flood times under unsteady conditions. So, this study has been concerned with the investigation of bed river erosion under the conveying pipeline at the conflict of river in unsteady condition. To achieve this aim, some effective hydrograph’s parameters were changed in different scenarios and the results were compared to the steady condition. The result showed the erosion’s ratio of unsteady condition to steady one was 34 to 69 percent. Also, the rise of flood hydrograph’s peak led to increasing depth erosion from 7% to 22%.

Synergistic relationships between mycorrhizal fungi (AMF) and organic compounds affect the mobility of the micronutrient elements in the rhizosphere and improve their bioavailability. In order to evaluate the effect of biochar and pruning waste compost of apple and grape trees, as well as AMF, on micronutrient bioavailability in calcareous soil at the wheat rhizosphere, an experiment was carried out in a completely randomized design under greenhouse conditions in a rhizobox study. Some factors including the organic sourses (pruning waste biochar, pruning waste compost and control), microbial inoculation (AMF and no inoculation) were considered. At the end of the growth period, Organic matter (OM) content and bioavailability of micronutrients including iron (Fe), Zinc (Zn), Copper (Cu) and Manganese (Mn) in the rhizosphere and their uptake by wheat plant were determined. The results indicated that OM, Fe, Zn, Mn and Cu were significantly increased in the rhizosphere soil under the influence of organic sources and mycorrhizal inoculation. Furthermore, biochar application in the mycorrhizal tratment resulted in 74.73% and 19.28% increase in Fe and Mn, as compared to non-inoculated conditions, in rhizosphere. The presence of mycorrhizal fungi increased the bioavailability of 94.66% and 29.54% Zn and Cu in the compost treatment, as compared to non-inoculated ones. Application of organic sources and mycorrhizal inoculation increased the micronutrient uptake and plant dry weight.

Soils pollution with heavy metals is due to the presence of various metals such as copper, nickel, cadmium, zinc, chromium and lead. Heavy metals have a negative effect on the biological parameters of soil, including size, activity and diversity of soil microbial population, as well as the enzymes involved in the deformation of such elements as P, N, C, and S. Thus, the activity of soil enzymes as a bioavailable agent is reflected as a cheap and fast method for the natural and anthropogenic distribution of heavy metals contamination. The purpose of this study was to investigate the effect of lead, humidity and their interaction on urease and phosphatase enzyme activity during a 10 week incubation period. Different levels of acetate lead (50,100, 150 and 200 mg/kg soil) were added to the plots containing two different moisture regimes (field capacity and flooding). The activity of urease and phosphatase (alkaline and acidity) was measured after 2,4,6,8 and 10 weeks of incubation. The results indicated different levels of lead had no significant effect on the activity of urease and acidity phosphatase. In contrast, high levels of lead significantly reduced the activity of alkaline phosphatase. Moreover, moisture served a different role in the activity of these enzymes, and it was related to the lead concentration and incubation time. Additionally, the function and interaction of lead, moisture and time were very influential on urease and phosphatase activity. Therefore, the above three characteristics are very important to study soil contamination for the polluted soils.

In arid and semi-arid ecosystems, isolated trees significantly influence the soil properties and can have a great impact on the soil fertility as well as the conservation and improvement of soil quality. This investigation was conducted to examine the influence of wild almond (Amygdalus arabica Olive.) trees having different ages on the physical and chemical soil properties. Soil samples were taken from the depths of 0-20, 40-60, 80-100 and 120-140 cm at two distances from the tree crown including the basal area (referred to as the rhizosphere) and the canopy edge in 3 replications for the 30, 50, and 130 year-old stands and also, in a control site, all in the Anjarak area, southeast of Baft city, Kerman Province. Soil properties including pH, EC, organic matter, calcium carbonate equivalent, available and non-exchangeable potassium and soil texture were measured in all samples. The results indicated that the measured soil properties in different depths in the study area had been influenced by the age and the canopy size of the wild almond trees. The highest and the lowest amount of pH were found in the control soil and the soils covered by 130 year-old trees, respectively. Besides, the electrical conductivity of the soil under the tree crown was more than that of the soil in the canopy edge. The accumulation of C, N, and other nutrients under the tree canopies resulted in the creation of fertility islands surrounding the trees. Furthermore, the soil physical and chemical properties were greatly improved with the increase in the tree age of Amygdalus arabica Olive. As the conclusion, wild almond trees could have very positive effects on soil properties. Therefore, it is essential to protect the trees. Otherwise, the risk of soil quality reduction would be increased and soils might become more susceptible to soil erosion.

In order to investigate P acquisition efficiency (PACE) and P utilization efficiency (PUTE) of the corn in the presence of phosphate-solubilizing microorganisms (PSMs), a factorial experiment was carried out in a completely randomized design in the greenhouse. The factors were including P sources (tricalcium phosphate (TCP) and rock phosphate (RP)) and microbial inoculation (control, soluble P as KH₂PO₄ (Ps), inoculation with bacteria (PSB), inoculation with fungi (PSF), co-inoculation of PSB + PSF). At the end of growth period, plant dry weight and P content in plant and soil available-P were measured and then PACE, PUTE and phosphorus efficiency (PE) indices were calculated. The results showed that, the interaction of phosphate source and microbial inoculation was significant with respect to shoot P content, soil P, PUTE and PE. PSF-TCP treatment increased 7 times shoot phosphorus content compared to cont-RP treatment.  PUTE in Cont-TCP treatment was 2.35 times higher than the TCP-P_S. The inoculation of PSF increased the PACE 1.61 times compared to co-inoculation of PSB + PSF tretment. Also, the highest PE index (99%) was obtained from SF-TCP treatment. In general, in calcareous soils with low P availability, inoculation of PSM with insoluble phosphorus sources can meet the phosphate needs of the plant.

Identification and investigation of changes in the area under cultivation of various crops seem to be essential for the management supply of crop production. In this study, r to identify and investigate change of the area under cultivation in major crop Hoseynabade Mishmast region in Qom province, we used the time series images of OLI and ETM sensors of landsat 8 and 7satellites, according to the crop calendar of this region. By using the vegetation index (NDVI) in the decision tree algorithm, the thresholds of this index were adjusted according to the major crops of this region; then a map of the cultivation pattern of the crop of this region was prepared. In order to evaluate the results, the statistics of the provinces agricultural jihad were used during 2005, 2009, 2014 and 2019 crop years. The results showed that by using the threshold of NDVI index, crops in this region in 2005 included wheat and barley and alfalfa, and their areas had an error of 17/1 and 6/1 percent in comparison with the statistics of agricultural Jihad, respectively; in 2009, wheat and barley, alfalfa and corn had an error of 0/5, 9/6 and 0/1 percent. Also, in 2014, wheat and barley, alfalfa, corn and sophie crops had an error equal to 4/9, 0.4, 11/4 and 2/4 percent, and the same crops in 2019 had an error 0/04, 11/6, 1/4 and 17/5 percent; that error was not significant. According to the results, the appropriate efficiency NDVI index in estimating crop cultivation area was determined by their phenology. Also, in 2009 and 2014, corn and sophie crops were added to the regions crops, and the area under crops cultivation in 2019 was increased, as compared to 2014.