Showing 64 results for Mica
M. S. Mousavi Dastenaei, H. Khademi,
Volume 18, Issue 70 (3-2015)
Abstract
Few investigations have been carried out on the ability of different plants to take up non-exchangeable potassium (K). The objective of this investigation was to examine the ability of different alfalfa cultivars to absorb K from phlogopite. An experiment was carried out with a completely randomized design with 3 alfalfa cultivars including Pickseed 2065 (MF), Rehnani (R) and Hamadani (H) grown in a quartz sand medium containing <53 micron sized phlogopite under complete and K-free nutrient solutions for a period of 6 months. During the growth period, the shoot was harvested 4 times. At the end of the experiment, the root was also separated from the growth medium and collected. Plant samples were extracted using the dry ash method and their K concentration was determined. Under the K-free nutrient solution, the highest shoot and root K concentration and uptake were found for the MF cultivar. The shoot and root K concentration in this cultivar were respectively 1.6 and 1.5 times higher than those in the R cultivar and 1.8 times greater than those in the H cultivar. The K uptake in the shoot and root of the MF cultivar was respectively 1.6 and 1.9 times higher than that of the H cultivar and 1.6 and 1.5 times higher than that of the R cultivar. Thus, in addition to other parameters, the type of plant variety should be taken into account when K requirement is evaluated.
T. Raiesi, A. Hosseinpur,
Volume 19, Issue 71 (6-2015)
Abstract
The ability of different soil tests in predicting soil phosphorus (P) is important in soils amended with municipal sewage sludge. The objective of the present study was to evaluate several chemical extractants to estimate available P for bean growing in 10 calcareous soils amended with municipal sewage sludge from Chaharmahal-Va-Bakhtiari province under the greenhouse conditions. For this purpose, the soil samples were incubated with sludge at a rate of 39-ton sludge ha–1. The amount of available P of the soil samples was determined by Olsen, Colwell, ammonium bicarbonate-DTPA, 0.01 M calcium chloride, BrayІ, ІІ, Mehlich І and ІІ methods. A pot experiment in a completely randomized design was conducted to evaluate the bean plant indices. The results showed that the amount of extractable P with the above methods decreased in the following order: Colwell> Bray ІІ> Mehlich ІІ> Olsen> Ammonium bicarbonate DTPA> Mehlich І> Bray І> 0.01M chloride calcium. The extractable P with 0.01M chloride calcium, Mehlich І, ІІ Colwell and Olsen methods correlated significantly with plant indices (P concentration and P uptake). Thus, mentioned methods could be used to estimate plant-available P in the soils amended with sewage sludge.
V. Moradinasab, M. Shirvani, M. Shamsaee, M. R. Babaee,
Volume 19, Issue 74 (1-2016)
Abstract
Mobarakeh Steel Complex has been using treated industrial wastewater for irrigation of green space to combat water shortage and prevent environmental pollution. This study was performed to assess the impact of short-, middle-, and long-term wastewater irrigation on soil quality attributes in green space of this complex. Soils were sampled from the wet bulb produced by under-tree trickles in three depths of forested lands irrigated with treated wastewater (for 2, 6 and 18 years) or groundwater. Several chemical, physical and biological characteristics of the soil samples were determined in the laboratory and compared to those of the native unirrigated soils as the controls. The results showed that pH was significantly reduced in the wastewater-irrigated soils as compared to the control. Organic matter content and cation exchange capacity significantly increased in the irrigated soils due to the incorporation of tree leaves into soil. Soil salinity also increased as the irrigation period increased because of the relatively high salinity of water and wastewater used for irrigation. Microbial basal respiration and arginine ammonification were greater in the irrigated soils in comparison to the control. In general, forestation and irrigation management have improved most of the soil quality indexes in the Mobarakeh Steel Complex green space, but some soil characteristics, such as salinity, need to be monitored and improved in future.
F. Jafari , H. Khademi,
Volume 21, Issue 1 (6-2017)
Abstract
Dust deposition phenomenon is an important climatic and environmental issue in arid and semi-arid regions. The objective of this study was to examine important characteristics of atmospheric dust in Kerman as one of the major cities in arid areas of our country with high potential of dust production. Dust samples were collected monthly using glass traps installed on the roof of 35 one-story buildings in Kerman for 7 months from April 20 to Nov. 20, 2012. To compare the results of atmospheric dust with those of soil, 60 surface soil samples (0-10 cm) from outside Kerman and 35 soil samples from urban areas were also collected. Some physical and chemical characteristics such as pH, electrical conductivity, organic matter, calcium carbonate equivalent, and particle size distribution were determined in dust and soil samples. The results of chemical analyses indicated that the amount of these properties is much higher than that in soils. Atmosphere dust particles appear to mainly originate from alkaline and saline soils surrounding the city of Kerman. Dust particle size distribution analysis further confirmed that dust particles have been transferred to Kerman city from medium to long distance areas. Temporal variability in dust chemical properties indicates that the contribution of anthropogenic and natural sources to urban dust in Kerman has seasonal changes. Based on the results obtained, it is necessary to control dust production outside and inside the city and its distribution in populated areas employing proper management practices.
F. Jalilian, B. Behmanesh, M. Mohammad Esmaeili, P. Gholami,
Volume 21, Issue 2 (8-2017)
Abstract
In this study, different indices of vegetation cover variations and different physicochemical properties of soil in three treatments of flood spreading, enclosure and grazing (control) were investigated and compared in in the region of Peshert in Mazandaran province. In order to measure different soil characteristics, 18 soil samples (six withdrawals at any treatment) from a depth of zero to 30 cm were taken from the desired treatments. In order to investigate different vegetation indices, a total of 90 plots (nine transects of 100 m) were run using systematic random sampling in the studied treatments and the necessary measurements were done (30 plots at any treatment). Then, in each of these plots, canopy coverage percentage was determined separately for each species and to evaluate and assess the diversity and richness in all three treatments, Shannon-Wiener and Simpson diversity indices and Menhink and Margalef richness indices were used. Finally, the data obtained from both sections of soil and vegetation in three studied treatments were compared and analyzed using one-way ANOVA and Duncan test. The results showed that floodwater spreading and enclosure significantly increased the percentage of sand and total Nitrogen, and significantly reduced the percentage of silt and potassium compared to control treatment. Also, percentage of clay and organic matter, soil pH levels, conductivity and soil phosphorus showed no significant differences in the treatments under study. The results of variance analysis of various indices of diversity, richness and species evenness showed that all indicators had significant responses in three treatments and the highest diversity and species richness were observed in flood spreading and enclosure treatments. Due to changes in soil properties and vegetation in flood spreading and enclosure treatments compared to the control treatment, it can be stated that operations of floodwater spreading and enclosure in the studied region has had positive effect on modification of soil texture, increasing the permeability of the soil and ultimately improvement of the vegetation.
M. Khoshravesh, M. Valizadeh,
Volume 21, Issue 2 (8-2017)
Abstract
Construction of a dam in the upstream of Tajan basin, as one of the human activities in order to provide drinking water, hydropower, agriculture, flood control or other purposes, can be effective on other sectors such as water resources. The purpose of this study is investigating the impact of Rajaei dam on groundwater resources in Sari-Neka plain during 26 years period (1985-2011) using geostatistical method, parametric and non-parametric tests. The results of statistical tests showed that groundwater table variation during 26 years has experienced insignificant upward trend. Quality factors such as EC, TDS, TH, Cl, SO4, Mg, Na and SAR had significant downward trend at 5% confidence level for Pearson and Kendall test. The Quality changes of groundwater resources in the region had good condition due to construction of dam. The results of spatial analysis for the study area using Kriging interpolation method in the three years for 1985, 1999, 2011 showed that in 1999 (the year of exploitation of the dam) most of the quality factors had reached the highest level from 1985 until the dam operation (1999) and then decreased to 2011. The results of this study showed that, agricultural activities after dam construction, operation of irrigation system and drainage network design of Rajaei dams, have raised the water table in northern part of the region and consequently had a significant impact on the quality of water resources.
A. Koochekzadeh, H. Hoveizeh, A. R. Yazdipour,
Volume 22, Issue 4 (3-2019)
Abstract
Since 2001, water main drainage of sugarcane farms located in the east side of Karoon River has been deviated to Shadegan lagoon. The average discharge and salinity of the drain water in spring and summer were 20 and 20.5 m3 sec-1 and 17.1 and 13.3 dS m-1, respectively. Therefore, there have been considerable changes in the lagoon water quality when compared to the time before entering the drain water. Therefore, an experiment was performed to investigate the effects of sugarcane waste water on the quality of Lagoon’s water. The results showed that the average salinity was increased significantly before and after the entrance of the drainage into different points. The average salinity in the sample point No.2 (along the entrance of the drainage) in summer was changed from 17.7 to 51.5 dS m-1. The results, therefore, revealed that after the entrance of drainage water to Lagoon, during summer time, water salinity and mineral concentrations were increased for all locations except the points of 1 (on the northern margin of Lagoon) and 3 (influenced by Jarahi River). Phosphate ion concentration was increased at all investigated locations, but the highest phosphate concentrations were observed at the location points of 1 and 2 in summer. Given the important role of this lagoon in the protection of animal and plant spices, it is essentially important for sugarcane production companies to adopt a special measure for the protection of Lagoon from any source of pollution.
H. Ghamarnia, F. Sasani, B. Yargholi,
Volume 23, Issue 1 (6-2019)
Abstract
Exploring the homogenous regions for site specific management is important, especially in the areas under different anthropogenic activities. This was investigated using multi-way analysis including Factor Analysis, Hierarchical Clustering Analysis and k means in the areas under long-term wastewater irrigation over a period of more than 40 years, in Shahre Rey, south of Tehran. By using Factor Analysis model, eight factors as eight geochemical groups were extracted to explain approximately 60% of the total variance related to 37 soil physicochemical properties. The most important groups included the nutrient elements (OM, OC and N), micronutrients (Mn and B), soil water adsorption capacity (Clay, Silt, Sand and CEC), salinity and osmotic pressure (EC, OP and TDS) and sodification (SAR and Na). The maximum values of Cophenet and Silhouette coefficients were equal to 0.77 and 0.83, respectively, dictating the selection of the average linkage approach in Hierarchical Clustering Analysis and three clusters in the k-average method with 19, 24 and 34 mapping units. The Thiessen Polygons method in GIS was applied to separate the geochemical groups in the form of mapping units. This output, which was, in fact, the combination of multi-way models and its visual representation in GIS under separated mapping units of study area, could present suitable management activities for the areas under each cluster.
H. Hasheminejada, M. Sayedbarzin, K. Jeirany, A. Taebi,
Volume 23, Issue 1 (6-2019)
Abstract
Detergents are the main organic pollutants in the industrial and domestic wastewater. Electro-chemistry methods are advanced purification methods developed with high efficiency features. The goal of this study was to investigate the possibility of using electrocoagulation and the complementary flocculation process to achieve the highest removal efficiency of the detergent COD. So, with iron electrode, synthetic samples at the concentrations of 500, 750 and 1000 mg/l (with COD of 217, 268 and 370 mg/l, respectively) and with the initial pH levels of 5, 7.3 and 9 were tested. Variable parameters during the electrocoagulation process included the current duration at 3, 5 and 10 minutes, and the current density was at 4, 10, 16 and 22 mA/cm2. The primary results showed that in the optimum conditions, the coagulation process and complementary flocculation could reduce the sample’s COD with an initial concentration of detergent (500 mg/l) from 217 mgO2/l to 81.30 mgO2/l. The electrocoagulation method could reduce the chemical oxygen demand to below the standard limit of environmental discharge (200 mgO2/l) and compensate for the possibility of the irrigation of green spaces due to water shortages.
M Rezaei Pasha, K Shahedi, Q. Vahabzadeh, A. Kavian, M. Ghajar Sepanlou, P. Jouquet,
Volume 23, Issue 2 (9-2019)
Abstract
One of the management practices to reduce the harmful effects of chemical fertilizers and to protect soil and water resources is applying a combination of organic and chemical fertilizers that can better than using them separately. Therefore, in order to understand and identify the effectiveness of this management practice, it is necessary to examine runoff and sediment production. This study was carried out in an agricultural sloping land located in the North of Iran, near Sari city. For this purpose, runoff measurement plots of 1 × 5 m were set up under natural rainfall based on a randomized block experimental design. Soil samples were measured at 0-10 and 10-20 cm depths. In this study, parameters such as runoff (volume, nitrate content, sediment yields), soil physical features (porosity and infiltration coefficient), and soil chemical properties (EC, OC, N, CEC, pH) were measured. The results showed that among soil chemical and physical properties, just N, EC and pH significantly influenced the Municipal Solid Waste Compost. A PCA was carried out, showing that these treatments explained 74.35% of the total variance of the results. Accordingly, it could be stated that using soil and water conservation management practices can rapidly significantly improve the soil properties in the sloping lands.
F. Soroush, A. Seifi,
Volume 23, Issue 2 (9-2019)
Abstract
Evaluation of groundwater hydro chemical characteristics is necessary for planning and water resources management in terms of quality. In the present study, a self-organizing map (SOM) clustering technique was used to recognize the homogeneous clusters of hydro chemical parameters in water resources (including well, spring and qanat) of Kerman province; then, the quality classification of groundwater samples was investigated for drinking and irrigation uses by employing SOM clusters. Patterns of water quality parameters were visualized by SOM planes, and similar patterns were observed for those parameters that were correlated with each other, indicating a same source. Based on the SOM results, the 729-groundwater samples in the study area were grouped into 4 clusters, such that the clusters 1, 2, 3, and 4 contained 73%, 6.2%, 6.7%, and 14.1% of groundwater samples, respectively. The increase order of electrical conductivity parameter in the clusters was as 1, 4, 3 and 2. The results of water quality index based on the entropy weighting (EWQI) showed that all of the samples with excellent and good quality (36.3% of samples) for drinking belonged to the cluster 1. According to the Wilcox diagram, 435-groundwater samples (81.7%) in the cluster 1 had the permitted quality for irrigation activities, and the other 285-groundwater samples were placed in all four clusters, indicating the unsuitable quality for irrigation. The Piper diagram also revealed that the dominant hydro chemical faces of cluster 1 were Na-Cl, Mixed Ca-Mg-Cl and Ca-HCO3, whereas the clusters 2, 3, and 4 had the Na-Cl face. This study, therefore, shows that the SOM approach can be successfully used to classify and characterize the groundwater in terms of hydrochemistry and water quality for drinking and irrigation purposes on a provincial scale.
O. Mohamadi, M. Heidarpour, S. Jamali,
Volume 23, Issue 3 (12-2019)
Abstract
Shortage of water resources and renewable per capita in last 30 years is put Iran on crisis threshold. Wastewater reuse is one of the battle solutions for water shortage and prevents wastewater depletion and environmental pollution. Thus, a pilot scale experiment was carried out to evaluate an integrated anaerobic/aerobic treatment for removal of BOD5 and COD, also to reduction of hydraulic retention time by considering optimum removal efficiency. The pilot was an anaerobic/aerobic bioreactor type under continuous-feeding regime based on a central composite design. The pilot was studied in different retention time and aeration was carried out between 5-15 hours. According to different retention times for COD removal efficiency, 24 hours was selected as optimum hydraulic retention time, that it is comparable to those obtained for 48 hours and over in plant roughly and could remove COD and BOD in acceptable ranges, results showed that average removal efficiency for BOD5 were 63.86 and 83.99 percent in aerobic and anaerobic phases, respectively. The average removal efficiency for COD was 76.5 and 74.35 percent for anaerobic and aerobic sections, respectively. The average removal efficiency for BOD5 and COD in this integrated aerobic-anaerobic pilot 95.24 and 94.8 percent, respectively.
A. Forghani, A. H. Forghani, M. Taghizadeh, B. Rabiei,
Volume 24, Issue 1 (5-2020)
Abstract
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.
A. Abdollahi, M. Norouzi Masir, M. Taghavi, A. Moezzi,
Volume 24, Issue 2 (7-2020)
Abstract
Nowadays, one of the ways to confront with the micronutrients deficiency is application of Nano materials to increase the availability of elements such as zinc for plants. Therefore, this study was conducted to investigate the effect of functionalized iron oxide nanoparticles and zinc sulfate chemical fertilizer on the zinc chemical forms in soil solution phase and its correlation with zinc concentrations and uptake in wheat. This study was carried out in a completely randomized design with three replications. Treatment consisted of functionalized iron oxide nanoparticles of Hydroxyl (OH), Carboxyl (COOH) and Amine (NH2), each at three levels (100, 200 and 300 mg.kg-1), ZnSO4 (40 kg.ha-1) and Control (without using iron oxide nanoparticles). At the end of the cultivation period, soil chemical properties such as pH, soil available zinc and dissolved organic carbon and concentrations and the uptake of zinc in plant were measured. The results showed that pH, available zinc and dissolved organic carbon content of soil solution were significantly affected by the treatments. The results obtained from the Visual MINTEQ Geochemical model showed that the highest amount of the free form of zinc (Zn2+) was obtained at the level of 300 mg.kg-1 of carboxyl iron oxide nanoparticles. Also, the experimental treatments significantly influenced the concentration of Zn-DOM species. The positive and significant correlation between Zn+2 and Zn- DOC species with the concentration and total Zn uptake of wheat indicated that these pools of Zn could be liable species in soil. The results of this study, therefore, showed that the application of functionalized iron oxide nanoparticles could help to improve soil conditions in order to increase the zinc availability for plants.
S. Shakeri, A. Azadi, M. Saffari,
Volume 24, Issue 4 (2-2021)
Abstract
Determining the relative distribution of each chemical form of the elements and their relationship with the physical, chemical, and clay mineralogical properties of soils can help researchers to achieve the sustainable agricultural management. The present study was conducted to evaluate the chemical forms of four micronutrients (Zn, Cu, Fe and Mn) in some surface and subsurface soils of Kohgiluyeh and Boyer Ahmad province and their relationship with the physical, chemical and mineralogical properties of the soils. The results showed that the exchangeable and sorbed chemical forms of the studied elements were very low and negligible, but the residual, carbonate, and organic forms had the highest to lowest values of the chemical forms of these elements, respectively. Examination of the correlation of the chemical forms of these elements with soil properties showed the effective correlation of organic carbon values with the Zn chemical forms; also, there was a correlation between clay, silt, cation exchange capacity and calcium carbonate and the chemical forms of Cu, Fe and Mn. The correlation between the quantities of clay minerals and the chemical forms of these elements showed that the amounts of different forms of the studied elements were directly related to 2:1 clay silicate minerals (especially vermiculite). Evaluation of Fe and Mn chemical forms also showed that the amounts of these elements were higher in the soils with developed profiles (Alfisol and Mollisol), the wetter climate and zeric moisture regime rather than in soils with non-developed profiles (Entisols and Inceptisols) and a drier climate and a ustic moisture regime. In general, the results showed that variations of soil forming factors such as climate (as well as the total amount of each micronutrients), could be effective on the chemical forms of micronutrients (especially on Mn and Fe); these can be effective in the management of weakly to highly-developed soils orders.
H. Motaghian, M. Shirmohammadi, A. Hosseinpur,
Volume 25, Issue 2 (9-2021)
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 (3-2022)
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.
A. Balvaieh, L. Gholami, F. Shokrian, A, Kavian,
Volume 26, Issue 4 (3-2023)
Abstract
Changes in nutrient concentrations of soil can specify optimal management of manure and prevent environmental and water resources pollution. The present study was conducted with the objective of changing macronutrients concentrations of Nitrogen, Phosphorus, and Potassium with amendments application of polyvinyl acetate, bean residual, and a combination of polyvinyl acetate + bean residual for time periods of one, two, and four months. The results showed that the application of soil amendments had various effects on changing Nitrogen, Phosphorus, and Potassium. The maximum amount of Nitrogen related to the treatment of bean residual at the time period of four months before simulation (with a rate of 44.62 percent) and minimum amount of nitrogen related to Polyvinyl acetate treatment at the time period of one month (with a rate of -1.92 percent). The minimum rate of Phosphorus was measured at the treatment of bean residual at the time period of one month before simulation (with a rate of 0.95 percent). The maximum amount of Potassium related to the treatment of Polyvinyl acetate at the time period of four months before simulation (with a rate of 189.35 percent) and the minimum amount of Potassium related to the combination of bean residual + Polyvinyl acetate at the time period of one month after simulation (with a rate of 40.66 percent). Therefore, the application of amendments has various effects on changing soil macronutrients at different time periods.
D. Khatibi Roudbarsara, A. Khaledi Darvishan, J. Alavi,
Volume 27, Issue 2 (9-2023)
Abstract
Soil erosion followed by sediment production is the most important phenomenon that causes soil and environment degradation in many areas and is increasing. Sediment fingerprinting is a method to identify sediment sources and determine the contribution of each source to sediment production. The present research was carried out to evaluate the relative erosion sensitivity of lithological units and to determine the contribution of each unit in bed sediment production using geochemical properties in the Vaz River located in Mazandaran province. The 33 soil samples were taken from the whole watershed and one sediment sample at the outlet of the watershed. Then, five tracers of B, Al, Sc, Mo, and Sn were selected as the optimal combination using three statistical tests range tests, Kruskal-Wallis, and discriminant function analysis. Finally, using optimal tracers and a combined multivariate model, the contribution of lithological units with very high (A), high (B), medium to high (C), and medium (D) sensitivity in bed sediment production were obtained using FingerPro statistical package and R software. The results showed that the contribution of lithological units with very high (A), high (B), medium to high (C), and medium (D) sensitivity in bed sediment production were 24.23, 50.77, 15.62, and 9.36%, respectively. Then, the specific contribution of each sensitivity class was also calculated to remove the effect of area on the results. The Qal lithological unit including the Quaternary sediments in the river bed and banks with very high sensitivity to erosion (A) and a specific contribution of 0.0807 % per hectare had the maximum contribution in bed sediment production in Vaz River.
A. Barikloo, S. Rezapour, P. Alamdari, R. Taghizadeh Mehrjardi,
Volume 27, Issue 4 (12-2023)
Abstract
Soil quality is one of the most crucial factors determining crop productivity and production stability. The soil's physical, chemical, biological, and ecological characteristics affect its quality. Numerous researchers have concentrated the evaluation on a small number of soil quality indicators because measuring all soil quality indicators would be time-consuming and expensive. This study looked at the spatial autocorrelation of soil quality in the southwest areas of the Urmia Plain to establish the minimal data set for quantitative assessment. To accomplish this, 120 composite soil samples were collected from a depth of 0 to 60 cm, and the soil quality index was then calculated using the IQI method in 4 modes: Total-Linear (IQIwL-TDS), Total-Nonlinear (IQIwNL-TDS), Minimum-Linear (IQIwL-MDS), and Minimum nonlinearity (IQIwNL-MDS). 22 physical and chemical characteristics were used to choose the data set. The characteristics of sand percentage, sodium absorption ratio, cation exchange capacity, Available phosphorus, active calcium carbonate, and nickel concentration were chosen as the minimum data set (MDS) using the decomposition method into principal components. The linear IQIMDS mode produced the greatest soil quality index result, whereas the non-linear IQIMDS mode produced the lowest. The non-linear mode of the IQI index has a greater correlation coefficient (R2=0.85) than the linear mode of the IQI index (R2=0.73), according to an analysis of the linear and non-linear correlation coefficient between the soil quality index with the total category and minimum data. The findings of computing the global Moran's index for study sets of IQI soil quality index data revealed that the soil quality data are not independent of each other and are spatially autocorrelated, distributed in clusters, and have spatial autocorrelation. Getis-ord GI statistics indicated that the eastern and southeastern parts of the research region comprise clusters with poor soil quality, salt marshes produced by Lake Urmia's drying up, and surrounding arid plains.
