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Mohsen Jalali - One of the best experts on this subject based on the ideXlab platform.
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assessment risk of phosphorus leaching from Calcareous Soils using soil test phosphorus
Chemosphere, 2017Co-Authors: Mohsen Jalali, Mahdi JalaliAbstract:Accurate estimation of phosphorus (P) leaching is important because excess P may reduce surface and ground water quality. Little attention has been paid to estimate P leaching from soil tests in Calcareous Soils. The relation between different soil tests P (STP), P sorption index (PSI) and degree of P saturation (DPS) and leaching of P were examined for assessing the risk of P loss from Calcareous Soils. Columns leaching repacked with native Soils were leached with either distilled water or 10 mM CaCl2 solutions, separately. Four leaching events were performed at four days, and 28.7 mm of distilled water or 10 mM CaCl2 solutions was applied at each leaching events. Compared with distilled water, CaCl2 had a small ability to solubilize P from Soils. Concentration of P in leachate in both leaching solutions was exceeding 0.1 mg l-1 associated with eutrophication. Cumulative P leached P was ranged from 0.17 to 18.59 mg P kg-1 and 0.21-8.16 mg P kg-1, when distilled water and 10 mM CaCl2 solutions were applied, respectively and it was higher in sandy clay loam Soils compared with clay Soils. Among evaluated environmental soil P tests, PCaCl2-3h (P extracted by 10 mM CaCl2 for 3 h), PCaCl2-1h (P extracted by 10 mM CaCl2 for 1 h) were more accurate than other soil P tests for predicting P concentration in the leachates in both leaching solutions and accounting for 83% and 72% of variation of P concentration, respectively. The water extractable P (WEP) (r = 0.771) and Olsen-P (POls)(r = 0.739) were significantly related to the leached P concentration using distilled water solution in a split line model, with a change point of 27.4 mg P kg-1 and 61.5 mg P kg-1, respectively. Various DPS were calculated and related to the leached P concentration. Based on P extracted by Mehlich-3 (PM3) and HCl (PHCl) and PSI, the change point of the relationship between leached P concentration and DPSM3-3 (PM3(PM3+PSI)×100) and DPSHCl-2 (PHCl(PHCl+PSI)×100) for both leaching solutions was approximately the same, thus a mean value of 49% for DPSM3-3 and 73% for DPSHCl-2 was obtained. Soils were grouped into four categories of increasing P leaching potential based on WEP, POls, and DPSM3-3. The results indicated that 8.00%-25.50% of the soil grouped in no risk category whereas 8.00%-13.70% of the Soils fell into the high risk category.
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Relation between various soil phosphorus extraction methods and sorption parameters in Calcareous Soils with different texture
Science of the Total Environment, 2016Co-Authors: Mohsen Jalali, Mahdi JalaliAbstract:The aim of this study was to investigate the influence of soil texture on phosphorus (P) extractability and sorption from a wide range of Calcareous Soils across Hamedan, western Iran. Fifty seven soil samples were selected and partitioned into five types on the basis of soil texture (clay, sandy, sandy clay loam, sandy loam and mixed loam) and the P extracted with calcium chloride (PCaCl2), citrate (Pcitrate), HCl (PHCl), Olsen (POls), and Mehlich-3 (PM3) solutions. On the average, the P extracted was in the order PHCl > PM3 > Pcitrate > POls > PCaCl2. The P extracted by Pcitrate, PHCl, POls, and PM3methods were significantly higher in sandy, sandy clay loam and sandy loam textures than clay and mixed loam textures, while soil phosphorus buffer capacity (PBC) was significantly higher in clay and mixed loam soil textures. The correlation analysis revealed a significant positive relationship between silt content Freundlich sorption coefficient (KF), maximum P sorption (Qmax), linear distribution coefficient (Kd), and PBC. All extractions were highly correlated with each other and among soil components with silt content. The principal component analysis (PCA) performed on data identified five principal components describing 74.5% of total variation. The results point to soil texture as an important factor and that silt was the crucial soil property associated with P sorption and its extractability in these Calcareous Soils. DPSM3-2(PM3PM3+Qmax×100) and DPScitrate(PcitratePcitrate+Qmax×100) proved to be good indicators of soil's potential P release in these Calcareous Soils. Among the DPS, 21% of Soils reported DPSM3-2, values higher than the environmental threshold, indicating build-up of P and P release. Most of the studied sandy clay loam Soils had exceeded the environmentally unacceptable P concentration. Various management practices should be taken into account to reduce P losses from these Soils. Further inorganic and organic P fertilizer inputs should be reduced in some parts of studied area.
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aging effects on phosphorus transformation rate and fractionation in some Calcareous Soils
Geoderma, 2010Co-Authors: Mohsen Jalali, Faranak RanjbarAbstract:Abstract Rate of phosphorus (P) transformation in Soils can significantly influence P fertility of Soils. The transformation rate and fractionations of P in 20 Calcareous Soils of varying properties were investigated. Phosphorus was added to the samples at rates of 200 mg kg− 1 soil. The samples were incubated for 3, 24, 168, 336, 504, 720, 1440, and 2160 h at 25 °C and Olsen-P was determined after each incubation period. The P release in the studied Soils was initially rapid followed by a slower release that lasted up to 2160 h. The transformation rate of Olsen-P for Soils was estimated by best fitted kinetic equation (parabolic) for above incubation periods. There were differences in the rates at which redistribution took place between Soils and P. Phosphorus in control and amended Soils were fractionated before and after 2160 h incubation by sequential extraction procedure, in which the P fractions were experimentally defined as exchangeable (KCl–P), Fe- and Al-bound (NaOH–P), Ca-bound (HCl–P), and residual P (Res-P) fractions. The results showed a sharp decrease in Olsen-P within 3 h after P addition. Relative NaOH–P in amended Soils ranged from 6.6 to 13.5%. Relative HCl–P, Res-P and KCl–P ranged from 49.9 to 71.2, 13.5 to 26.7, and 7.4 to 13.3%, respectively. There were changes in the proportional distribution of P in all the Soils during 2160 h of incubation with amended P. In general the proportions of P associated with the most weakly bound fraction (KCl–P) tended to decrease, with corresponding increases in the NaOH–P and HCl–P fractions during the incubation. The principal component analysis showed that the first four components explained 77.1% of the overall variation.
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evaluation of phosphorus leaching from contaminated Calcareous Soils due to the application of sheep manure and ethylenediamine tetraacetic acid
Environmental Earth Sciences, 2009Co-Authors: Mohsen Jalali, H. OstovarzadehAbstract:Organic amendment application to heavy metal contaminated Soils may contribute to leaching of phosphorus (P). The objectives of this study were to determine the influence of sheep manure and ethylenediamine tetraacetic acid (EDTA) on the P leaching from a wide range of Calcareous contaminated Soils. Glass tubes, 4.9 cm diameter, and 40 cm long, were packed with contaminated soil. The resulting 20 cm long column of Soils had bulk density of 1.3–1.4 g cm−3. The columns were leached with distilled water, 0.01 M EDTA, 0.01 M CaCl2 or sheep manure extract (SME) solutions. The breakthrough curves for P were different and the amounts of P leached varied considerably between different Soils and leaching solutions. The amounts leached with SME were less than the amount added through the SME, indicating that some P was retained by the soil, mainly due to preliminary sorption of organic ligands on to the soil with the creation of new sorbing surfaces. The amount leached with EDTA solution varied from 9.9 to 46.3% of the extractable P when 15 pore volumes had passed through the column. Low amounts of P were leached by 0.01 M CaCl2, which is likely to be due to the high concentration of soluble Ca used in the solution. Thus, among leaching solutions the application of EDTA and SME on contaminated Calcareous Soils might enhance the mobility of P and large amounts of P will be leached, leading to contamination of ground and surface waters.
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effect of sodium and magnesium on kinetics of potassium release in some Calcareous Soils of western iran
Geoderma, 2008Co-Authors: Mohsen JalaliAbstract:Abstract The rate of potassium (K) release from Soils can significantly influence their K fertility. Sodium (Na), calcium (Ca), and magnesium (Mg) in poor quality (sodic or saline) irrigation water participate in ion-exchange processes resulting in displacement and release of K from minerals into solution. This study determined the effect of sodium adsorption ratio (SAR) and Ca:Mg ratio of water on K release of some Calcareous Soils in western Iran. Nine different solutions at a total electrolyte concentration of 100 mmol c l − 1 and three levels of SAR (5, 15, 45) each with Ca:Mg ratios of 1:3, 1:1, or 3:1, prepared using solutions of NaCl, CaCl 2 , and MgCl 2 were used to extract K from the Soils. Significantly different quantities of K were extracted by the solutions. The maximum (average of five Soils) (985 mg kg − 1 ) and the minimum (387 mg kg − 1 ) K were extracted by an SAR 5 solution with a Ca:Mg ratio of 1:3 and an SAR 45 solution with Ca:Mg ratio of 3:1, respectively. The importance of Mg versus Ca can be related to the specific ion effect. The kinetics of K release from Soils consisted of two phases, an initial rapid phase followed by a slow phase of K release from Soils. The two phases of K release are characteristic of a diffusion-controlled process. Based on the correlation coefficients, power function, parabolic diffusion, and Elovich equations adequately described K + release, whereas a first order equation did not. The K release rate for the Soils was estimated by parabolic equation from the above solutions. The constant b (mg kg − 1 min − 1/2 ) in the parabolic equation was defined as the release rate and for the Ca:Mg ratio of 1:3 was 96.5 , 55.9, and 35.1.for the SARs of 5, 15, and 45, respectively. The results imply that K extraction from Soils could be increased during use of saline irrigation water containing high Mg concentration. The additional K released may be more readily available to plant roots but could also be leached down below the root zone. The results suggest that long-term use of saline irrigation water with a high Mg content could lead to enough leaching of K from soil under saline and sodic conditions that K fertilization management may need modification.
S Moharrami - One of the best experts on this subject based on the ideXlab platform.
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competitive adsorption of trace elements in Calcareous Soils of western iran
Geoderma, 2007Co-Authors: Mohsen Jalali, S MoharramiAbstract:Abstract Trace elements distribution between the solid and soil solution phases is a key issue in assessing the mobility and retention of trace elements in Soils. In a competitive system where Soils are contaminated with several trace elements metal adsorption reactions become important. This study was conducted to assess the competitive sorption of cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni) and mangenese (Mn) in surface samples of ten Calcareous Soils from western Iran. Sorption isotherms were characterized using linear, Freundlich and Langmuir equations. Most sorption isotherms were well described by the Langmuir equation. All Soils showed greater sorption capacity and binding strength for Cu than the other trace elements. On the basis of distribution coefficient values for the metal concentration of 25 mg l− 1 (Kd25) and maximum sorption capacity (Q) for each soil and trace element, the selectivity sequence was obtained. The three greatest adsorption sequences found were Cu > Zn > Cd > Ni > Mn, Cu > Ni > Zn > Cd > Mn and Cu > Cd > Zn > Ni > Mn. Copper, Zn and Ni were the trace elements most strongly adsorbed by all Soils, whereas Mn and Cd were the least adsorbed in the competitive situation.
Azam Jafari - One of the best experts on this subject based on the ideXlab platform.
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phosphorus sorption kinetics in Calcareous Soils of selected arid and semi arid toposequences and its relationship with plant growth
The South African Journal of Plant and Soil, 2010Co-Authors: Azam Jafari, H Shariatmadari, Y Rezainejad, Sh GhalamiAbstract:An array of kinetic equations has been used to describe time-dependent sorption of P by Soils. We investigated P sorption kinetics in Calcareous Soils at upper-, mid-, and lowerslope positions of two arid and two semi-arid landscapes and its relationship with plant growth and P uptake by wheat. The P sorption kinetics was described by the rival kinetic models in the order: power function Elovich > parabolic diffusion > first order > second order equation, all indicative of diffusion kinetics with a slow chemical reaction. The rate parameters showed positive correlations with CBD-extractable Al and active calcium carbonate contents and negative correlations with organic carbon content. The P sorption rate at 0.25 h and 72 h after initiation of the experiment (SRin and SRf, respectively) and the P sorption rate parameters derived from the Elovich (1/β), power function (ab) and parabolic diffusion (R) equations were significantly correlated with the shoot dry matter and P uptake by wheat. The soil P sorption rate and the P sorption kinetics parameters generally increased from upper to lower slope positions. This phenomenon was more significant in semi-arid than in arid toposequences.
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phosphorus release kinetics and availability in Calcareous Soils of selected arid and semiarid toposequences
Geoderma, 2006Co-Authors: Hossein Shariatmadari, Mehran Shirvani, Azam JafariAbstract:Abstract Rate of phosphorus (P) release from solid to solution phase may control the lability of P in soil environments. Kinetics of P release from Iranian Calcareous Soils at upper-, mid-, and lower-slope positions of two arid and two semiarid landscapes were determined and relations between the P release rate parameters and P uptake by wheat were investigated. The kinetic data was best described by simple Elovich equation as evidenced by the relatively higher values of determination coefficient ( r 2 ) and the relatively lower values of the standard error of estimate. Power function, parabolic diffusion and first order equations also well fitted the time-dependent P release data. The initial and final P release rates (i.e., DR in and DR f ) that were estimated at reaction times of 0.25 and 72 h and the P release rate parameters derived from the Elovich (1 / β ), power function ( ab ) and parabolic diffusion ( R ) equations were well-correlated with the wheat shoot dry matter yield production and the amount and/or the concentration of P in wheat tops both at an early (4 weeks) and a later (10 weeks) stages of growth confirming the importance of P release rate in plant P nutrition in the Soils. The rate parameters showed positive significant relationships with clay, active calcium carbonate and citrate–bicarbonate–dithionate (CBD)-extractable Al contents of the Soils. The soil properties promoting the P release rate and the P release kinetic parameters increased from the upper-slope to the lower-slope positions of the arid toposequences.
Mahdi Jalali - One of the best experts on this subject based on the ideXlab platform.
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assessment risk of phosphorus leaching from Calcareous Soils using soil test phosphorus
Chemosphere, 2017Co-Authors: Mohsen Jalali, Mahdi JalaliAbstract:Accurate estimation of phosphorus (P) leaching is important because excess P may reduce surface and ground water quality. Little attention has been paid to estimate P leaching from soil tests in Calcareous Soils. The relation between different soil tests P (STP), P sorption index (PSI) and degree of P saturation (DPS) and leaching of P were examined for assessing the risk of P loss from Calcareous Soils. Columns leaching repacked with native Soils were leached with either distilled water or 10 mM CaCl2 solutions, separately. Four leaching events were performed at four days, and 28.7 mm of distilled water or 10 mM CaCl2 solutions was applied at each leaching events. Compared with distilled water, CaCl2 had a small ability to solubilize P from Soils. Concentration of P in leachate in both leaching solutions was exceeding 0.1 mg l-1 associated with eutrophication. Cumulative P leached P was ranged from 0.17 to 18.59 mg P kg-1 and 0.21-8.16 mg P kg-1, when distilled water and 10 mM CaCl2 solutions were applied, respectively and it was higher in sandy clay loam Soils compared with clay Soils. Among evaluated environmental soil P tests, PCaCl2-3h (P extracted by 10 mM CaCl2 for 3 h), PCaCl2-1h (P extracted by 10 mM CaCl2 for 1 h) were more accurate than other soil P tests for predicting P concentration in the leachates in both leaching solutions and accounting for 83% and 72% of variation of P concentration, respectively. The water extractable P (WEP) (r = 0.771) and Olsen-P (POls)(r = 0.739) were significantly related to the leached P concentration using distilled water solution in a split line model, with a change point of 27.4 mg P kg-1 and 61.5 mg P kg-1, respectively. Various DPS were calculated and related to the leached P concentration. Based on P extracted by Mehlich-3 (PM3) and HCl (PHCl) and PSI, the change point of the relationship between leached P concentration and DPSM3-3 (PM3(PM3+PSI)×100) and DPSHCl-2 (PHCl(PHCl+PSI)×100) for both leaching solutions was approximately the same, thus a mean value of 49% for DPSM3-3 and 73% for DPSHCl-2 was obtained. Soils were grouped into four categories of increasing P leaching potential based on WEP, POls, and DPSM3-3. The results indicated that 8.00%-25.50% of the soil grouped in no risk category whereas 8.00%-13.70% of the Soils fell into the high risk category.
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Relation between various soil phosphorus extraction methods and sorption parameters in Calcareous Soils with different texture
Science of the Total Environment, 2016Co-Authors: Mohsen Jalali, Mahdi JalaliAbstract:The aim of this study was to investigate the influence of soil texture on phosphorus (P) extractability and sorption from a wide range of Calcareous Soils across Hamedan, western Iran. Fifty seven soil samples were selected and partitioned into five types on the basis of soil texture (clay, sandy, sandy clay loam, sandy loam and mixed loam) and the P extracted with calcium chloride (PCaCl2), citrate (Pcitrate), HCl (PHCl), Olsen (POls), and Mehlich-3 (PM3) solutions. On the average, the P extracted was in the order PHCl > PM3 > Pcitrate > POls > PCaCl2. The P extracted by Pcitrate, PHCl, POls, and PM3methods were significantly higher in sandy, sandy clay loam and sandy loam textures than clay and mixed loam textures, while soil phosphorus buffer capacity (PBC) was significantly higher in clay and mixed loam soil textures. The correlation analysis revealed a significant positive relationship between silt content Freundlich sorption coefficient (KF), maximum P sorption (Qmax), linear distribution coefficient (Kd), and PBC. All extractions were highly correlated with each other and among soil components with silt content. The principal component analysis (PCA) performed on data identified five principal components describing 74.5% of total variation. The results point to soil texture as an important factor and that silt was the crucial soil property associated with P sorption and its extractability in these Calcareous Soils. DPSM3-2(PM3PM3+Qmax×100) and DPScitrate(PcitratePcitrate+Qmax×100) proved to be good indicators of soil's potential P release in these Calcareous Soils. Among the DPS, 21% of Soils reported DPSM3-2, values higher than the environmental threshold, indicating build-up of P and P release. Most of the studied sandy clay loam Soils had exceeded the environmentally unacceptable P concentration. Various management practices should be taken into account to reduce P losses from these Soils. Further inorganic and organic P fertilizer inputs should be reduced in some parts of studied area.
Qing Chen - One of the best experts on this subject based on the ideXlab platform.
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arsenic adsorption on layered double hydroxides biochars and their amended red and Calcareous Soils
Journal of Environmental Management, 2020Co-Authors: Xing Gao, Yutao Peng, Lili Guo, Qiong Wang, Chungyu Guan, Fan Yang, Qing ChenAbstract:Highly efficient amendments for controlling arsenic (As) pollution in Soils are imperative to improve soil quality and enhance food production. In the present study, corn stalk biochar was functionalized with three kinds of layered double hydroxides (i.e., Mg-Al-LDH, Zn-Al-LDH, and Cu-Al-LDH) using a simple co-precipitation method. The synthesized LDH biochar composites (LDH@BCs) exhibited better adsorption capacity and affinity for As due to their enhanced anion exchange capacity and reactive surface hydroxyl groups identified by XRD, FTIR and XPS. Arsenic (As) bioavailability and leaching characteristics of spiked red and Calcareous Soils (150 mg As/kg) amended with or without LDH@BCs were investigated using soil column. The Zn-Al-LDH@BC decreased the As (V) migration and increased pak choi (Brassica chinensis L.) growth in both red and Calcareous soil. These results indicated that LDH modified biochar is an effective way to overcome the shortfalls of unmodified biochar in mitigating the As contamination and provide a basis for further exploring the potential of biochar-based soil amendments for environmental remediation.