Soil science
O. Toorajzadeh; H. Piri; A. Naserin; M.M. Chari
Abstract
IntroductionAppropriate and practical use of agricultural waste reduce the pressure on the environment. Recently, there has been significant promotion of biochar utilization in agricultural lands. It serves as a valuable source of organic material for enhancing plant growth and as an effective soil amendment ...
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IntroductionAppropriate and practical use of agricultural waste reduce the pressure on the environment. Recently, there has been significant promotion of biochar utilization in agricultural lands. It serves as a valuable source of organic material for enhancing plant growth and as an effective soil amendment to improve soil properties. Due to its unique chemical and physical properties, biochar can be used as a soil conditioner and has many benefits for optimal agricultural and environmental management. Studies have shown that biochar is a useful amendment for improving the physical and chemical properties of soil and effective in maintaining organic matter and soil moisture. Materials and Methods This research was conducted with the aim of investigating the effects of biochar on the physical and chemical properties of soil under conditions of water stress and irrigation using saline water. The experiment was carried out in a factorial based on a completely randomized design with three replications in greenhouse conditions. The treatments include three irrigation water treatments (60, 80, and 100 percent water requirement of the plant, respectively, I1, I2, and I3), three treatments of biochar prepared from northern forest trees at a temperature of 300 degrees Celsius (0, 2, and 4 percent by weight of potting soil, respectively, B1, B2, and B3) and three water quality treatments (with electrical conductivity 1, 4 and 7 dS/m, respectively, S1, S2 and S3). The pots were weighed every other day and at each level of biochar and salinity, the water deficit up to the agricultural moisture level was calculated based on the changes in the pot's weight. After harvesting (in the first half of April 2022), in order to investigate the effect of biochar on the amount of soil nutrients and some physical and chemical parameters of the soil under the conditions of water stress and irrigation water salinity, sampling was done from the soil of each pot. The samples were taken to the laboratory and parameters of apparent and actual specific gravity, acidity and salinity of the soil, percentage of nitrogen, phosphorus and potassium absorbable of the soil were measured in the laboratory. Referring to the yield to irrigation water ratio, water productivity is obtained by the following relation (Payero et al., 2009): WP=Y/IR, where, WP represents water productivity (kg/m3), Y denotes the yield (kg/ha), and IR shows the amount of irrigation water (m3/ha). Analysis of variance for the results obtained from different treatments was conducted using SAS software (SAS 9.1, SAS Institute, Cary, NC, USA). The mean values of the main factors and interactive effects were compared using the Duncan method at the 1% and 5% levels of significance. Results and DiscussionThe results showed that the amount of biochar, irrigation water and water salinity and their mutual effects had a significant effect on the measured parameters at the probability level of one and five percent. Adding 2 and 4 mass percent biochar to the soil increased the amount of phosphorus (35 and 60%, respectively), potassium (57% and 61%), nitrogen (83% and 91%), pH (13% and 13%) and electrical conductivity (EC) (13% and 57%) of the soil. By adding 2% and 4% of biochar to the soil, the actual specific gravity of the soil decreased by 13% and 21%, respectively, and the apparent specific gravity decreased by 11% and 22%, respectively. The actual and apparent specific gravity of the soil decreased by adding biochar to the soil. Decreasing the depth of irrigation water and increasing water salinity increased the amount of phosphorus, potassium, nitrogen, pH and EC of the soil. The amount of irrigation water had no significant effect on the apparent and actual specific gravity, however, the salinity of the irrigation water caused a significant increase in the apparent and actual specific gravity of the soil. Although the addition of biochar to the soil increased the nutrients required by plants in the soil, high amounts of biochar in the soil should be used careful, because the addition of this organic matter to the soil at high levels increased soil EC significantly. Based on the findings derived from the research, the utilization of biochar is recommended as a viable approach for enhancing both the chemical quality and productivity of nutrient-poor and sandy soils.
Irrigation
Abdorreza Vaezihir; Vahede Aghaie; Mehri Tabarmayeh
Abstract
IntroductionDetermining the capture zone of water resources is a strategic approach proposed at the national level of water resources management in Iran. One of the important actions for this purpose is protection of karst water resources, which are considered one of the vital sources for supplying water ...
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IntroductionDetermining the capture zone of water resources is a strategic approach proposed at the national level of water resources management in Iran. One of the important actions for this purpose is protection of karst water resources, which are considered one of the vital sources for supplying water due to the widespread karst formations in this country and the limitation of groundwater resources in alluvial aquifers. Generally, water flows out through the springs in the karst system. The land area where the water contributes to the spring is called the spring's capture zone. The study and analysis of the recession curve of the springs, the area extending from a discharge peak to the base of the next rise, along with the other physical characteristics of springs such as electrical conductivity is a useful indicator for getting knowledge about the condition of the catchment area and other properties of the heterogeneous karst terrain. In estimating the water budget, unlike the non-karst areas where the surface runoff or the outflow is considered the main factor in the estimated water budget, the recharge component is an important factor in the karst domain. The difference between hydrogeological and hydrological (topographic) catchments is one of the obvious features in karst landscapes. The identification of these basins or their boundaries is possible by combining geology and topography information. Soufiyan Cement Company in the vicinity of Chelleh Khanehe Olya spring located in Moro Mountain is associated with the creating social problems due to the expansion of mining activities and the negative impact on spring water in this area. Therefore, this study aims to determine the catchment area and the capture zone of the Chelleh Khanehe Olya spring by determining the protective boundary for the extraction of limes by the Soufiyan cement factory to prevent the negative impact of this factory on the spring.Materials and MethodsIn this research, the hydrograph of the recession curve related to a rainfall event has been analyzed by taking into account the mean monthly discharge rate of spring to determine the sub-regimes of diffuse and conduit flow by employing the following equation:Qt=Q0e-αt (1)Where Qt is the discharge rate at time t, Qo reveals the discharge at the initial time, and α is a recession coefficient.In addition, The Qmax/Qmin ratio has been calculated to estimate the flow type and the degree of karstification in the catchment area.In the next step, to determine the Chelleh Khanehe Olya spring catchment area and its capture zone, spring hydrogeological boundaries were determined and investigated using the SCS method and estimating the area's water budget. Due to the lack of sufficient rainfall and groundwater discharge information in this region, the water budget for a given period (2019-2020) has been computed indirectly by measuring the monthly discharge rate from the selected stations. After collecting the required data, the following equation developed by Milanovich (1989) has been used to estimate the water budget as follows:P=E+R+I (2)Where P, E, R, and I denote precipitation (P), evaporation at the basin level (E), runoff (R), and recharge to the aquifers (I). All the parameters are in mm units.Results and DiscussionAnalyzing the variation of electrical conductivity along with the discharge rate indicates that by decreasing the discharge rate from 2.5 l/s to 8.1 l/s, the electrical conductivity increase from 463 µs/cm to 500 µs/cm, reflecting an increase in the volume of the reservoir, the dilution of the aquifer. The hydrograph recession curve during 2019-2020 indicated two laminar and turbulent sub-regimes. Micro regimes α1 (01.002) and α2 (0.013) represented that the dominant system of karst development in the region is diffuse. The high density of fractures and the lack of purity of lime are the main reasons for the weak development of the karst fracture in the region, which the Chelekhaneh Alia spring recession curve analysis, maximum to minimum ratio of discharge, and karstification coefficient confirmed this issue. Determining the catchment basin using geological, hydrogeological information, and water budget showed that the hydrological and hydrogeological boundary of the spring is different. The protected zone of Chelekhane Alia spring, which includes the total hydrogeological basin and the Cretaceous limestone area below the level of the spring, was estimated to be about 184,000 square meters (18 hectares). According to the findings of this research, Sufian Cement Factory does not have the right to enter the hydrogeological boundary to extract limes, and on the other hand, to prevent the water level from decreasing due to the excessive extraction of lime as a result of the excavation depth reaching the level of the water table, it suggests to extract from the unsaturated part of the aquifer (unsaturated limes) to prevent the flow rate of Chele Khana spring from decreasing and even drying it up.ConclusionAnalyzing the discharge rate, electrical conductivity, hydrograph recession curve, and its recession coefficient(α=0.002), revealed that the dominant flow in the system is diffuse, which results from the high density of fractures and region lithology consisting of impure cretaceous limestone. Since the result revealed the inconsistency between hydrological and hydrogeological boundaries, the geological profile of the site was prepared and the spring of the catchment was estimated. Based on the findings of this research, the Chelle Khanehe Olya capture zone consists of the hydrogeological area, obtained from the groundwater budget estimation, and the protective boundary for the limestone below Cheleh Khaneh Olya spring (the unsaturated zone of the area's limestones), which covers an area of about 18 hectares.
Soil science
F. Alizadehgan; M.A. Gholami; S. Shiukhy Soqanloo
Abstract
IntroductionIncreased agricultural activities, the occurrence of successive droughts, and limited freshwater resources, along with increasing population, have made a priority for the importance of protecting water resources in programs of developed and developing countries. Due to the climatic conditions ...
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IntroductionIncreased agricultural activities, the occurrence of successive droughts, and limited freshwater resources, along with increasing population, have made a priority for the importance of protecting water resources in programs of developed and developing countries. Due to the climatic conditions in Iran, which has a wide range of arid and semi-arid characteristics, facing the challenge of water resources crisis, is inevitable. Therefore, the use of wastewater is very important.Materials and MethodsThis research was conducted in the research farm of Sari University of Agricultural Sciences and Natural Resources (SANRU), which has a silty clay soil texture. The latitude and longitude of the region are 36º 40ʹ N and 53º 04ʹ E, respectively. Its height above sea level is 21 meters. According to Demarten classification, Sari city has a temperate humid climate. The long-term average temperature of Sari is 11.18 °C and the total long-term rainfall is 780 mm. In order to evaluate the wastewater effects on soil chemical characteristics, microelements concentrations, heavy metals accumulation and Maize yield (Single Cross 704), an experiment was carried out as factorial based on a completely randomized design with treatments included; Water source factor (wastewater (A1), well water (A2)), Irrigation (subsurface method (I1) and (drip method (I2)) with three replication in 2018-2019 under lycimetric conditions, at the Sari Agriculture and Natural Resources University (SANRU), Iran.Results and DiscussionAccording to this study results, the effect of type of irrigation source on soil electrical conductivity, soil microelements and heavy metals accumulation of the soil was significantly different (P ≤ 0.01). The highest soil electrical conductivity with a value of 1.8 dS.m-1 was observed in the conditions of using treated wastewater. The highest amount of total nitrogen, phosphorus and potassium were related to the source of treated wastewater with values of 0.086, 24.2 and 222.2 mg.kg-1, respectively. The results showed that the accumulation of soil Pb (0.07) and Cd (0.014 mg.kg-1) in irrigation with treated wastewater increased compare to the well water source by 0.05 and 0.010 mg.kg-1, respectively. Also, the effect of irrigation method and the interaction effect of source and method irrigation on soil chemical characteristics, microelements concentration and heavy metals accumulation were not significant. The use of wastewater by increasing soil stability improves soil physical condition, increases soil fertility, increases photosynthetic products, increases the efficiency of plant photosynthetic system and ultimately improves plant growth. The use of subsurface irrigation resulted in a 67% increase in grain yield and 28% increase in biomass productivity compared to the drip method. Adequate nutrients during the reproductive growth stage of the plant play an important role in grain growth. Therefore, it can be said that the nutrients in the wastewater have increased the grain yield compared to using the well water source. Because the wastewater contains nutrients and micronutrients such as; nitrogen, phosphorus, potassium, calcium, zinc and iron were relative to the well water source and increased maize grain yield. The results showed that the use of effluent compared to well water, caused the absorption of more heavy metals lead and cadmium in the grain, leaf and stem of maize. Due to the use of wastewater water source, the amount of Pb uptake among different parts of the maize, with values of 27.2, 22.5 and 20.5 mg / g, respectively, related to the grain, leaf and stem. However, the uptake of Cd in the grains, leaves and stems was 2.32, 1.35 and 2.01 mg / g, respectively. According to the results, the high concentration of heavy metals Pb and Cd due to the use of wastewater in the grain sector directly threatens human health. Also, the concentration of heavy metals Pb and Cd in the leaf and stem parts of corn, by endangering the health of livestock and poultry, indirectly affects human health.ConclusionThe results showed that irrigation with treated wastewater due to its richness in nutrients and microelements, improves soil fertility and creates favorable conditions by increasing soil organic matter and mineral for plant growth. Also, according to the permissible threshold values of the concentration of heavy metals Pb and Cd in plants, the accumulation of heavy metals Pb and Cd in the grain, stem and leaf of single cross 704 corn, will not be a problem for consumers. Optimal use of wastewater can increase soil fertility and the ability of plants to absorb nutrients from the soil and ultimately increase plant yield.
Gh. Rahimi; F. Karimi
Abstract
Introduction: Salinization of soil has been reported as a problem in many parts of the world. Salinization could occur either as a result of natural processes e.g. high concentrations of salt in parent materials or groundwater and/or anthropogenic actions such as over-irrigation. The salinization probably ...
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Introduction: Salinization of soil has been reported as a problem in many parts of the world. Salinization could occur either as a result of natural processes e.g. high concentrations of salt in parent materials or groundwater and/or anthropogenic actions such as over-irrigation. The salinization probably affects the chemical and physical properties of soil, soil microbiological processes, plant growth, and soil fauna. Both quantity and quality of water, however, are the most important eco-factors needed for earthworm survival and development, and also biodegradation processes. Materials and Methods: In order to investigate the effect of irrigation water salinity on the survival and growth of earthworm Eisenia Fetida, an experiment was conducted in a completely randomized design with three replications under environmental conditions of the laboratory of Soil Sciences Department of Bu-Ali Sina University in Hamedan. The different types of water used in this study were: distilled water and saline water made with NaCl salt with electrical conductivity (EC) of 2, 4, 6, and 8 dS m-1. The experiment was carried out using completely randomized design in plastic containers of size 19 × 13 × 8 cm. Ten earthworms per container used in each exposure regime were introduced into the relevant test salinity by placing them on the surface and allowing them to burrow in. The test containers were covered with perforated lids to limit water loss due to evaporation and kept in 16 hours light, 8 hours dark at 25°C in a climate chamber for 42 days. Sampling was done at 3, 15, 21, 27, 33, 39, and 42 days after earthworms were introduced to the substrates to investigate mortality and weight changes of earthworms. The LC50 (concentration at which 50% of the earthworms are killed) and the EC50 (effect concentration at which a 50% reduction in a measured parameter) values for the salts expressed as conductivity (dS m-1) were calculated on day 27 and 42 by using the Probit Analysis. Results and Discussion: On day 3, no significant effect of salinity on percentages of survival was found. The survival rate of Eisenia fetida was significantly affected in the EC range used during 42 days (Table 2). The irrigation with distilled water (EC0) had the highest survival rate while the irrigation water with EC 8 dS m-1 had the lowest value. During the 39 days of exposure, no significant difference was found in survival rate of earthworms between EC 2, EC 4 and EC 6 dS m-1, but at the end of day 42, the salinity levels with EC 8 dS m-1 had a significant effect on percentage of earthworm survival in which 91.68% mortality occurred. The mean weight change of earthworms exposed to water with EC 2 dS m-1 was not significantly different (p < /em> < 0.01) from those exposed to the distilled water during 39 days, but there was a decrease in earthworm weight on day 42. The calculated LC50 for mortality after 27 and 42 days was 7.5 and 4.31 dS m-1, respectively, and EC50 for growth was 7.94 and 6.82 dS m-1, respectively. Conclusion: Our results showed that increased salinity had harmful effects on the growth and mortality of the earthworms (Eisenia fetida). Salinity can have detrimental effects on earthworms at concentrations considered safe for many plant species. We determined 42 day LC50 for mortality 4.31 dS m-1 (2521 mg lit-1). The EC50 for growth was 6.82 dS dS m-1 (3989 mg lit-1). The weight of earthworms was significantly affected by NaCl and dispersion analysis showed that NaCl concentration had a statistically significant influence on the weight of earthworms. The argument for using NaCl is that it is the predominant salt in most saline environments particularly in wastewaters. Since the salt type is dependent on the source of the contamination, it is, therefore, possible that other salts apart from NaCl could be the main compounds in saline toxicity in a specific area. The results of the current study suggest that the effects of salinity depend on the salt composition. Therefore, it would be important to assess the type of salt ions in soil in risk assessment, as this affects the extent of toxicity to soil organisms.
azam habibipoor; Ali Talebi; Ali Akbar Karimian; Farhad Dehghani; Mohammad Hosain Mokhtari
Abstract
Introduction: Salinity is one of the problems of arid and semi-arid soils. Identification and classification of saline/alkaline soils is necessity for dealing with difficult situations and correct management. Considering the nature of salinity data and selection of befitting methods to process data before ...
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Introduction: Salinity is one of the problems of arid and semi-arid soils. Identification and classification of saline/alkaline soils is necessity for dealing with difficult situations and correct management. Considering the nature of salinity data and selection of befitting methods to process data before use artificial neural network, can result in better simulations. The aim of this study was to investigate the optimal method for data processing to enhance the accuracy of surface soil salinity simulation and improve the efficiency of decision tree algorithm.
Materials and Methods: The study area was 88940.4 hectares of Marvast plain located in central Iran (54° 5´to 54° 18´ east longitude and 30° 10´to 30° 35´north latitude). This region faces with problems of soil and water resources salinity. In this study, the effect of data processing on increasing accuracy of simulation of soil surface salinity was assessed in Marvast region using decision tree algorithm. For this purpose, the decision tree algorithm was applied and simulation was performed using three approaches i.e. original data, logarithmic data and standardized data. Finally, five statistics including R، Rmse، %Rmse، MAE and Bias were calculated to evaluate the performance of used simulation methods.
Results and Discussion: In this study, when the logarithmic data was used, the composition of band 7 – elevation was identified as the most appropriate condition. The created tree can estimate the soil salinity by five laws:
If elevation is less than 1519, then the average of surface soil salinity will be 147.9 ds/m.
If elevation is between 1519 to 1569.9, then the average of surface soil salinity will be 43.6 ds/m.
If elevation is between 1569.9 to 1609.8, then the average of surface soil salinity will be 17.5 ds/m.
If elevation is more or equal to 1609.8 and pixel value of band 7 (ETM+ sensor) in selected point is less than 0.295, then the average of surface soil salinity will be 4.7 ds/m.
If elevation is higher or equal to 1609.8 and pixel value of band 7 (ETM+ sensor) in selected point is more than or equal to 0.295, then the average of surface soil salinity will be 1.4 ds/m.
For the approach of using the logarithmic data, decision tree algorithm used two parameters out of 46 independent variables introduced into the model. R، Rmse، %Rmse، MAE and Bias for this method was computed to be 0.76, 0.49, 38.57, 0.37 and -0.14, respectively. The application of logarithmic data was recognized as the best method considering the lower calculated error and its less input requirement. Using Easy fit software, the distribution of salinity data was found to be Log Pearson 3. Thus, the use of logarithmic data improved model performance. Our findings were in agreement with those of Afkhami et al (2015) who increased the simulation accuracy of suspended sediment with artificial intelligence methods (Artificial neural networks and ANFIS) using logarithmic data.
Conclusions: As effective factors for soil salinity simulation vary in different regions, application of a unique method and indicator to estimate soil salinity in deferent region may not be possible.. The application of semi intelligent algorithm which limits user intervention and selects effective parameters for simulation would increase the simulation accuracy. Furthermore, considering the nature of salinity data and selection of befitting methods to process before using decision tree algorithm can effectively improve model performance. The current study was conducted to select an appropriate approach to enhance the simulation accuracy of surface soil salinity. The results demonstrate that the performance of decision tree algorithm as one of the artificial intelligence models can be affected by input data. In this study, Log-Pearson3 distribution was defined as the distribution of salinity data. Moreover, despite existence of significant correlation coefficients for three simulation methods, the error was lower when logarithmic data was used. Since the probability distribution of salinity data in the studied area was logarithmic (Log-Pearson 3), the reduction in error rate can be attributed to the probability distribution of salinity data.
Leila Bakhshandehmehr; Mohammad Reza Yazdani; Ali-Asghar Zolfaghari
Abstract
Introduction: In recent years, due to the reduction in surface water, utilization of groundwater has been increased to meet the growing demand of irrigation water. The quality of these water resources is continually changing, due to the geological formations, the amount of utilization, and climatic parameters. ...
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Introduction: In recent years, due to the reduction in surface water, utilization of groundwater has been increased to meet the growing demand of irrigation water. The quality of these water resources is continually changing, due to the geological formations, the amount of utilization, and climatic parameters. In many developing countries, the irrigation water is obtained from poor quality groundwater resources, which in turn, creates unfavorable circumstances for plant growth and reduces the agricultural yield. Providing adequate water resources for agricultural utilization is one of the most important steps needed to achieve the developmental targets of sustainable agriculture. Thus, this necessitates the assessment and evaluation of the quality of irrigation water. There are many proposed methods to determine the suitability of water for different applications, such as Piper, Wilcox, and Schoeller diagrams. Zoning of quality and suitability of irrigation water could represent the prone and critical areas to groundwater exploitation. Garmsar alluvial fan is one of the most sensitive areas in the country where traditional agriculture practices had turned into modern techniques and excessive exploitation of groundwater has caused an intensepressure on aquifers and increased water salinity. The aim of this study is to evaluate the suitability of groundwater for irrigation in a 10-year period (2002-2012) and its changes in this basin.
Materials and Methods: Garmsar alluvial fan is located in the North-West of Semnan Province. Semnan is situated in the Southern hillside of the Alborz Mountains, in North of Iran. The study area includes the agricultural land on this alluvial fan and covers over 3750 hectares of this basin. In order to evaluate the quality of groundwater in this area, the electrical conductivity and sodium absorption ratio of 42 sample wells were calculated. The raster maps of these indicators were obtained using Geo-statistical techniques. The suitability of irrigation water was determined by Wilcox diagram. Upon evaluating the data distribution and testing the data from Klomogrov-Smirnov normality test, normalization of the data was performed in SPSS software. Spatial correlation and spatial structure of variables were analyzed by drawing their semi-variograms in GS+ software. The most accurate variogram model was selected according to the lowest Residual Sums of Squares (RSS) and the highest correlation coefficient (R2). Interpolation and zoning of the indicators were performed in ArcGIS software and the Quality classes were determined.
Results and Discussion: According to the results of Kolmogorov-Smirnov test, none of the data series had normal distribution. Therefore, they were normalized through calculating the logarithm of variables. Fitting and the selection of variograms were performed in GS+ software and after the calculation of errors, kriging method with Guassian model was determined as the best fitting model. The correlation coefficient was 0.896 for electrical conductivity and 0.99 for sodium absorption ratio. Interpolation of indicators in ArcGIS implied fewer measurements of these indicators in north of the study area (Hableh-Rood inlet). The maximum measurement of indicators was observed on the western edge of the alluvial fan. In total, the values of both electrical conductivity and a sodium absorption ratio indicators in the western half of the area, in the vicinity of the third period domes, were more than the eastern half. The result of the water classification using Wilcox diagram represented the unsuitability of groundwater for irrigation in all of the study area. The area with unusable groundwater for irrigation has increased over the 2005 – 2009 period.
Conclusion: In this study, relying on the use of GIS and Geo-statistical methods, the quality of Garmsar basin groundwater has been evaluated. The electrical conductivity was applied to monitor water salinity, and Sodium absorption ratio was used to monitor alkalinity. The interpolation of these indicators was performed by Kriging method and Guassian fitting model. Likewise, in other studies, the Kriging method was introduced as an appropriate method for the interpolation of chemical parameters of the groundwater. The accuracy of various fitting models in the prediction of interpolated values differed according to the number and the distribution of sample points. In the current study, the Guassian fitting model was determined as the best model to interpolate both of the indicators. According to the maps, it seems that the third period domes in the western margin of the study area have a great influence on the quality of Garmsar’s surface water and groundwater. In total, the groundwater of Garmsar basin didn’t poss high suitability for irrigation, and was classified into two unsuitable and unusable classes. Moreover, according to the maps, the maximum area of unusable groundwater for irrigation in the area was observed in 2008.
M. Hajhashemkhani; M. Ghobadi Nia; Seyed Hassan Tabatabaei; A. Hosseinpour; S. Houshmand
Abstract
Recently, wastewater is one of the water resources for irrigation due to the scarcity of water resources. In this regard, using adsorbents such as zeolites is recommended to improve the characteristics of the wastewater. Although the results show that natural zeolite decrease amount of pollutions but ...
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Recently, wastewater is one of the water resources for irrigation due to the scarcity of water resources. In this regard, using adsorbents such as zeolites is recommended to improve the characteristics of the wastewater. Although the results show that natural zeolite decrease amount of pollutions but at the same time decreases the permeability of the soil, which could adversely affect the soil. This study was done in 2012 at the Shahrekord University, 27 PVC columns were used to study the effect of modified zeolite particles on permeability and quality of the wastewater. The experiment consisted of two factors the type of the microzeolite (natural zeolite, modified zeolite) and application procedure of the micro zeolite (mixed, layer) with three replications and in total had 7 treated. Injection of wastewater into the soil was through waterlogging and repeated fifteen times with a weekly frequency. Volume of wastewater used in each injection is equal "nv". In frequency injections of 1,3,5,7,11,15 infiltration was measured using Falling Heads. The results showed that treatment of modified zeolite included mixed, middle layer and layer on the surface had the highest infiltration rate respectively and treatment with natural zeolite included mixed, middle layer, layer on the surface had lowest infiltration rate. Further modified treatments decreased Ca effluent rate 111% with respect to natural Zeolite and therefore caused modified treatments to decrease SAR amount 45% with respect to control treatments and 132% with respect to natural zeolite.
F. Akbarnejad; A. Astaraei; A. Fotovat; M. Nasiri Mahalati
Abstract
Recently Application of municipal solid waste compost and sewage sludge on the farm land had received considerable attention. These organic wastes provides a valuable source of organic matter and enhances crop yield and soil fertility by improving soil physical, chemical and biological properties. To ...
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Recently Application of municipal solid waste compost and sewage sludge on the farm land had received considerable attention. These organic wastes provides a valuable source of organic matter and enhances crop yield and soil fertility by improving soil physical, chemical and biological properties. To evaluate the influences of municipal solid waste compost (MSWC) and sewage sludge (SS) on chemical properties of soil an experiment was conducted with Municipal solid waste compost at 0, 15, 30 ton/ha (C0, C15 and C30) and sewage sludge at 0, 15, 30 ton/ha (S0, S15 and S30) in a factorial experiment based on completely randomized design with three replications in greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad. Results showed that municipal solid waste compost and sewage sludge and their interaction effects had significant effects on soil chemical properties. With increasing amounts of municipal solid waste compost and sewage sludge, organic carbon and electrical conductivity of soil increased. Portion of Sewage sludge compared to municipal solid waste compost in increasing of organic nitrogen is lower. The most amount of soil organic nitrogen was observed in municipal solid waste treatments. Also use of these wastes together decreased soil acidity.
