Showing 11 results for Motaghian
Alireza Hosseinpur, Hamidreza Motaghian, Tahereh Raeisi Gahrooee1,
Volume 17, Issue 64 (summer 2013)
Abstract
Information about potassium (K) release characteristics in the Chaharmahal-va-bakhtiari soils is limited. In this study, K release kinetics of fifteen calcareous soils was investigated. Soil samples were extracted using successive extractions with 0.01 M CaCl2 and citric acid solutions for 2-2017 h at 25±1 0C. Moreover, soil K was determined using 6 chemical extraction methods. The results showed that released K ranged from 111 to 411 mg kg-1in calcium chloride solution and from 177 to 1199 mg kg-1 in citric acid solution for 2017 h. Amounts of extracted K using any extraction methods were different. Result of kinetics study and chemical methods indicates that K supplying power of the soils is different. A plot of cumulative amounts of released K shows a discontinuity in slope at 168 h. Thus, two equations were applied to the total reaction time (2 to 168 and 168 to 2017 h). Moreover, results showed that release kinetics of K conformed fairly well to parabolic diffusion, simplified Elovich and power function models in two segments in 0.01 M CaCl2 and citric acid. In addition, results showed that correlation between released K by using 0.01 M calcium chloride and citric acid and extracted K using chemical methods was significant. The results of this research showed that kinetic studies and soil testing could be used for evaluating K fertility status of studied soils.
H. Motaghian, A. Hosseinpur, F. Raiesi, J. Mohammadi,
Volume 17, Issue 65 (fall 2013)
Abstract
Studying the distribution of Zn in the soils allows investigating their mobility and bioavailability. In this research, 10 calcareous soil samples were selected, and sewage sludge-amended (1% w/w) and -unamended (control) soils were incubated for 1 month. Before planting, fractions of Zn were determined, three seeds of wheat were planted in each pot and after 8 weeks, they were harvested. Results showed that all Zn fractions were increased by sewage sludge addition. Results of pot experiment indicated a significant correlation between Zn concentration in wheat with exchangeable (r=0.92**) and Zn associated with Fe and Mn oxides (r=0.76*) in control soils. In addition, significant correlation coefficient was found between Zn associated with Fe and Mn oxides and Zn uptake index (r=0.86**). Moreover, wheat responses were significantly correlated with Zn exchangeable (r=0.71*- 0.84**) in amended soils. Yield was correlated with Zn associated with carbonates and Zn associated with Fe and Mn 0.69 and 0.75, respectively. Zn uptake index was correlated with Zn associated carbonates (r=0.64*). Therefore, the exchangeable and Zn associated with Fe and Mn oxides in control soils and the exchangeable and Zn associated carbonates and Zn associated with Fe and Mn oxides in amended soils could be used as available fractions of wheat.
H. R. Motaghian, A. R. Hosseinpur, F. Raiesi, J. Mohammadi,
Volume 18, Issue 67 (Spring 2014)
Abstract
Rhizosphere is a small zone and has quite different chemical, physical, and biological properties from bulk soil. This research was performed to study the available Zn and its fractions in the wheat rhizosphere and bulk soils by using rhizobox at greenhouse conditions. Total organic carbon (TOC), dissolved organic carbon (DOC), microbial biomass carbon (MBC) and available Zn using 7 chemical procedures and Zn-fractions were determined in the rhizosphere and bulk soils. The results indicated that TOC, DOC and MBC in the rhizosphere were increased significantly (P<0.01). Zn extracted using several chemical extractants (except 0.01 M CaCl2) in the rhizosphere were significantly (p<0.05) higher than in the bulk soils. Also, concentrations of Zn-fractions (except carbonate-associated) in the rhizosphere were significantly (p<0.05) different from concentrations of Zn-fractions in the bulk soils. Results indicated that correlation between uptake index and extracted Zn using DTPA-TEA and Mehlich 3 were significant (p<0.05). Moreover, significant correlation (p<0.05) between uptake index and exchangeable Zn and Zn associated with iron-manganese in the wheat rhizosphere and bulk soils were found. The results of this research illustrated that available Zn and its fractions in the rhizosphere soils are different from the bulk soils. Therefore, application of the rhizosphere soil would be recommended in the study on these properties after planting.
H. R. Motaghian, A. R. Hosseinpur, J. Mohammadi, F. Raiesi,
Volume 20, Issue 75 (Spring 2016)
Abstract
Zinc (Zn) is one of the essential micronutrients for plant growth and its deficiency frequently occurs in calcareous soils. But, a suitable extractant for estimation of plant-available Zn in calcareous soils, amended with sewage sludge, has not been presented yet. The aim of this research was to assess several chemical extractants (7 extractants) for estimation of available Zn in calcareous soils amended (1% w/w) and unamended with sewage sludge. Results showed that Mehlich 3 and Mehlich 1 extractants extracted the highest and the lowest concentrations of Zn in both amended and unamended soils, respectively. All wheat indices (wheat yield, Zn concentration and Zn uptake) increased by sewage sludge addition. Besides, the results indicated that in unamended soils, significant correlations were found (r=0.65*- 0.91**) between extracted Zn using AB-DTPA, DTPA-TEA and Mehlich 3 extractants and different wheat indices. On the contrary, in sewage sludge-amended soils, only the correlation between extracted Zn using Mehlich 2 and Zn concentration was significant (r=0.83**). According to this study findings, the suitable extractant for extracting wheat-available Zn is thoroughly different in calcareous soils amended and unamended with sewage sludge.
S. Z. Atar Shahraki, A. R. Hosseinpur, H. R. Motaghian, Sh. Ghorbani,
Volume 22, Issue 1 (Spring 2018)
Abstract
The study of the kinetics of non-exchangeable potassium (NEK) release is very important for a better understanding of K availability for plants in different soils. Moreover, aggregates with different sizes have different effects on the release of nutrients. Therefore, the aim of this study was to examine the release of NEK in 5 calcareous soils of chaharmahal-va- bakhtiari province, and small and large aggregates (<250 μm and >250 μm) using CaCl2 0.01 M at 25±1ºc for 2-2017 h. The results showed that cumulative released NEK in soils, and small and large aggregates was 173.5-372.7, 215.1-426.1 and 178.9-381.5 mg kg-1, respectively. The results revealed that coefficients of the cumulative released NEK in small aggregates was lower than those of the soils and large aggregates. Based on the coefficient of determination (R2) and standard error (SE), the released NEK was well described by the first order, the power function, parabolic diffusion, and simplified Elovich equations. The rate coefficients of the release of K were different in different soils. The cumulative released amount of K and its rate of release in a solution of calcium chloride in small aggregates was more than those of large aggregates.
S. Z. Kiani Harcheghani, A. R. Hosseinpur, H. R. Motaghian,
Volume 23, Issue 2 (Summer 2019)
Abstract
Adsorption is one of the most important processes controlling the concentration of zinc (Zn) in the soil solution. The presence of nutrient anions in the solution can affect Zn2+ adsorption. In this study, the effect of orthophosphate, nitrate and chloride anions on the Zn2+ adsorption in five calcareous soil samples of Chaharmahal-va-Bakhtiari province was investigated. In order to study the Zn adsorption isotherms, solutions containing 25, 50, 75, 100, 150 and 200 mg/L Zn of ZnSO4 source were used in KH2PO4, KNO3 and KCl electrolytes (electrolytes concentration equal to 50 mM). The Freundlich, Langmuir, and linear equations were used to investigate the ability to describe the Zn adsorption. Based on the results, the Freundlich and Langmuir equations could describe the Zn adsorption. The results of this study showed that Zn in the presence of orthophosphate anion had the maximum adsorption capacity and an adsorption intensity higher than that of chloride and nitrate anions; meanwhile, in comparison with nitrate and orthophosphate anions, adsorption energy (k), maximum buffering capacity (MBC), and distribution coefficient (kf) in the presence of chloride anion were higher (p< 0.05). The results of this study, therefore, showed that in the presence of anion orthophosphate, Zn adsorbed more intensity and strongly, while adsorption energy was less than the presence of the other two anions. Therefore, it could be concluded that Zn and phosphate fertilizers should not be applied together in the soil.
F. Shahbazi, A. R. Hosseinpur, H. R. Motaghian,
Volume 24, Issue 1 (Spring 2020)
Abstract
In order to increase the available Phosphorous (P), chemical fertilizers are applied; however, P chemical fertilizers are transformed into low available forms over time. Organic amendments could be effective in improving the efficiency of P fertilizers. The aim of this study was to investigate the effect of P fertilizers and vermicopost on the availability and fractions of P and maize (Zea Mays L.) indices in a calcareous soil. This study was performed in a factorial completely randomized design with three replicates. The experimental factors included chemical fertilizer (0 and 50 mg/kg P) and vermicopost (0 and 1 %W). After 2 months of planting in greenhouse, the shoots of maize were removed and the maize indices (P concentration, dry matter and P uptake) were determined. Then, the soil samples taken from each pot, P available, and P fractions were evaluated by a modified method developed by Hedley et al (1982). The results showed that the effect of the interaction beyween P fertilizer and vermicopost on the available P was significant. Also, the interaction of P fertilizer and vermicopost on the soluble and exchangeable P (P<0.05) and organic P (P<0.01) was significant. By applying the P fertilizer or % 1 vermicompost, all P fractions (except Ca bound P) were increased. The results, therefore, showed that the effect of the interaction between P fertilizer and vermicopost on P concentration, dry matter and P uptake was not significant (P>0.05). Vermicopost application increased the dry matter from 6.9 to 10.5 g pot-1, while application of 50 mg kg-1 P as fertilizer increased the dry matter from 7.7 to 9.7 g pot-1. Also, by adding vermicopost (11.1%), the i P uptake was increased, as compared to 50 mg kg-1. The results, therefore, indicated that the beneficial effect of vermicompost on the dry matter and P uptake in maize was more than that of the chemical fertilizer. Moreover, P fertilizer and manure could influence P fractions and P availability.
H. Motaghian, M. Shirmohammadi, A. Hosseinpur,
Volume 25, Issue 2 (Summer 2021)
Abstract
Iron (Fe) is an essential micronutrient for plants and its deficiency occurs in calcareous soils. However, a suitable extractant for the estimation of plant-available Fe and its critical level in calcareous soils depends on the type of soil and plant. The objective of the present study was to evaluate several chemical extractants to estimate available Fe and its critical level for corn growing in calcareous soils from Chaharmahal-Va-Bakhtiari Province. The amount of available Fe was measured by DTPA-TEA, AB-DTPA, 0.01 M calcium chloride, Mehlich IІ, and Mehlich ІІI extractants. At the end of the experiment, corn was harvested, and dry weight, Fe concentration in the plant, and the amount of Fe uptake by corn were determined. Extracted Fe had a significant correlation with all extractants used with maize indices. . The highest correlation coefficients were determined between the DTPA-TEA (0.32-0.94) and AB-DTPA (0.43–0.96) methods and the plant indices. The results of this research showed that the DTPA-TEA and AB-DTPA methods were the most suitable extractants for predicting available Fe content in these soils and the critical level of Fe extracted by these extractants was 2.81 and 3.67 mg kg-1.
E. Mirzakhani, H. Motaghian, A. Hosseinpur,
Volume 25, Issue 4 (Winiter 2022)
Abstract
Pollution of the environment by heavy metals, especially soil pollution with cadmium (Cd), is one of the most important environmental problems. Also, salinization of soils due to a decrease in irrigation water quality reduces plants growth. To investigate the effect of sugarcane bagasse biochars and salinity on Cd available and Cd fractions in a contaminated soil (15 mg kg-1 Cd), an experimental factorial design in a completely randomized design including (1) biochar factor with control, 1% (w/w) bagasse, 1% (w/w) biochar 400 °C and 1% (w/w) biochar 600 °C, and (2) salinity factor with control, 20, and 40 mmol kg-1 as sodium chloride were performed in 3 replications. The amount of available Cd was determined by the DTPA-TEA method and the Cd fractions were determined by Tessier et al. (1979). The results showed that biochar and salinity had no significant effect on soil pH (P > 0.05) but increased soil EC (P < 0.05). Interaction of biochar and salinity was not significant (P > 0.05) on available Cd and Cd fractions. Biochar application reduced Cd -DTPA-TEA (P < 0.05), whereas salinity increased Cd -DTPA-TEA (P < 0.05). Application of biochar prepared at 600 °C reduced (P < 0.05) exchangeable Cd (23.8%) and increased (P < 0.05) Cd associated with iron and manganese oxides (25.2%) and residual (15.6%) compared to the control. The results showed that salinity had no significant effect on the Cd fractions (P > 0.05) and soil treated with sugarcane bagasse biochar can reduce Cd available due to changing the Cd distribution from unstable forms to stable forms.
F. Khafi, A.r. Hossienpour, H. Motaghian,
Volume 26, Issue 2 (ُSummer 2022)
Abstract
One of the significant factors affecting biochar properties is the pyrolysis temperature. This study aimed to investigate the effect of pyrolysis temperature on the properties and fractionation of Zn and Pb in biochars produced by sewage sludge. Biochars were prepared at temperatures of 300 to 700 °C and the physicochemical properties, availability, and fractionation of Zn and Pb were investigated. The results showed that pH, pHzpc, percentage of calcium carbonate, cation exchange capacity, specific surface area, and porosity in biochars were higher than in the feedstock. By increasing biochar production temperature, the mentioned properties increased. FT-IR revealed that the OH functional group is present in free form, either in the structure of C-OH and -COOH and aliphatic-CH2 groups in the sewage sludge. By converting sewage sludge to biochar, the intensity of these peaks decreased. In contrast, peaks representing complex aromatic structures appeared. The availability of Zn and Pb in biochar was reduced as compared to sewage sludge. The results of fractionation indicated that sewage sludge has bio-availability and toxicity of Pb and Zn. the amount of oxide and residual fractions of these two metals increased by converting sewage sludge to biochar at different temperatures. Therefore, it seems that biochar production from sewage sludge reduces the toxicity and bio-availability of Zn and Pb. Also, by incrementing the temperature of production, the bio-availability potential (bonding with organic matter), and non-toxicity (residual) of these metals increased.
E. Mirzakhani, H.r. Motaghian, A.r. Hosseinpur,
Volume 27, Issue 3 (Fall 2023)
Abstract
In addition to the distribution of elements in the soil solid phase, element species in the solution are also very important due to their importance of providing elements for root uptake. For a deeper study of the chemical cycle of elements in saline soils treated with biochar, the study of speciation is very useful and provides a method to reduce or transform the toxicity caused by toxic elements in saline soils. Therefore, to investigate the effect of biochar on Cd speciation in two saline calcareous soils, 15 mg kg-1 Cd as cadmium chloride was added to the soil sample (200 g), and the soils were incubated for three weeks at 25±2 °C at 80% field capacity. After the incubation period, salinity levels of 20 and 40 mmol kg-1 as sodium chloride (equal to 3.65 and 7.30 dS m-1) were added to the soils. Then, the 1% (w/w) of the sugarcane bagasse and biochars produced at 400 and 600 °C were added to the soils, and then incubated for three months at 25±2 °C at 80% field capacity. At the end of the incubation period, for the speciation of Cd in the soil solution (in a 1 to 2 ratio), the concentration of dissolved cations and anions in the soil samples was measured. The results showed that the interaction between salinity, biochar, and soil on Cd2+, CdCl+, CdCl20, and Cd(SO4)22- was significant. The application of biochar in sandy soil reduced (p <0.05) the concentration of CdCl+, CdCl20, CdSO40, and CdOH+ species compared to the control soil, while it did not affect clay soil. Also, salinity caused by sodium chloride in sandy soil increased the concentration of CdCl+ and CdCl20 species and decreased CdSO40 and CdOH+ species compared to the control soil (p <0.05). The results showed that biochar in saline sandy soil was more effective than clay soil in reducing Cd toxicity.
