Research Paper
Masoomeh Ahmadzadeh; Ebrahim Sedaghati; Roohallah Sabri-Riseh; Asghar Rahimi; Narges Hatami; Ali Akbar Mohammadi Mirik
Abstract
Introduction; Rising global demand for food, along with the limitation of arable land, has posed a major challenge for agricultural researchers. Given that the development of agricultural lands is not practically possible, most attention should be focused on increasing the production yield per unit area. ...
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Introduction; Rising global demand for food, along with the limitation of arable land, has posed a major challenge for agricultural researchers. Given that the development of agricultural lands is not practically possible, most attention should be focused on increasing the production yield per unit area. One of the basic approaches to increase crop yield is the consumption of more types of inputs, especially chemical fertilizers, despite their application poses problems for humans, soil and the environment. In addition to decreasing the use of chemical fertilizers, organic fertilizers can be considered as a suitable solution to solve this problem. Organic compounds and biomass are the main factors of soil fertility, maintain soil fertility as well as its productivity. One way to increase soil organic substance is the applying organic fertilizers such as living compounds (bacteria, yeast, Azolla) and non-living compounds (compost tea, amino acids, humic acid and fulvic acid). Arbuscular Mycorrhizal Fungi are cosidered as beneficial microorganisms. Arbuscular mycorrhizal fungi promote plant growth by establishing a symbiotic relationship with plants. The colonization of plant roots by these fungi increases plant resistance to biotic and abiotic stresses, enhances growth through increasing elements uptake, improves the water flow of plants, and protects plants against diseases. Due to the importance of some food products such as Zea mays, investigation of various aspects of the mycorrhizal fungi application and their effect on these products is important.Materials and Methods; In this study, in order to investigate the efficacy of some organic compounds and microorganisms on the colonization of arbuscular mycorrhizal fungi and uptake of some elements trough the plant roots, a factorial experiment in greenhouse conditions was conducted in a completely randomized design with three replications for 3 months. This study involved the fungal factor at three levels, Funneliformis mosseae (FM), Rhizophagus intraradices (RI), and Rhizophagus irregalaris (RIr), and the organic enhancer factor at seven levels (Azolla, P. fluorescens VUPf5 bacterial strain, Amino acid complex, Humic acid, Yeast, Bacterial siderophore and Compost tea).Results and Discussion; The results of this study showed that the highest root mycorrhizal colonization percentage by Funneliformis mosseae (FM) was observed in bacterial (93%), humic acid (90%) and Azola (76%) treatments, respectively. Treatments of Azola and humic acid with 96% and compost tea with 82% showed the highest effect on R. intraradices (Ir) colonization. Also, Azola (96%) and compost tea (90%) had the greatest effect on the root colonization percentage by R. irregalaris (Rir). According to the results, the main increase in root colonization percentage by three mycorrhizal species was observed in Azola, humic acid, compost tea and bacterial treatments. The results showed that some compounds increased the concentration of nutrients in the roots and shoots of the treated plant. The function of these compounds is as a stimulant in mycorrhizal fungi and it seems mainly via root stimulation and rooting and creating signals related to the roots of the plant and mycorrhizal fungi. According to the results, all mycorrhizal species significantly increased the amount of phosphorus (69.5%) in the shoot under the compost tea application. Treatment of amino acid along with R. irregaluris caused to increase in the concentration of iron, compared to the control. Application of R. intraradices along with amino acid increased manganese concentration by 2.87 times compared to the control. Simultaneous application of siderophore and RI, FM and Rir increased the concentration of zinc 2.16, 2.55 and 1.81 times compared to the control, respectively. Results of the present study indicated an increase in the uptake of elements by all three species of mycorrhizal fungi and the performance of these fungi accompanied with compost tea, amino acid complex and siderophore had a better outcomes compared to the control. The highest uptake of phosphorus, zinc and manganese was observed using R. intraradices and iron in inoculated plant with R. irregaluris. The mean comparison of different treatments effect revealed no significant differences between non- mycorrhiza and mycorrhiza-treated samples, while in comparison with the control, their differences were significant. Overall, concomitant use of mycorrhizal fungi with azolla, bacterial and humic acid has the greatest increase in the mycorrhizal root colonization and treatments of compost tea, amino acid complex and siderophore has the highest impact on nutrient content increase in plant.Keywords: Arbuscular mycorrhizal fungi, Elements content, Root colonization, Synergistic effect
Research Paper
Mansoreh Bameri; Farhad khormali; Hossein kheirabadi
Abstract
Introduction. Soil is an essential part of the environment. It is important for the production of food and other crops. Soil erosion and sedimentation are complicated and least well-known environmental problems worldwide (Mahmoodabadi et al, 2014). Recently, the application of compounds that modify and ...
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Introduction. Soil is an essential part of the environment. It is important for the production of food and other crops. Soil erosion and sedimentation are complicated and least well-known environmental problems worldwide (Mahmoodabadi et al, 2014). Recently, the application of compounds that modify and improve soil quality and also reduce soil erodibility has been more thoroughly researched. These compounds are known by the common name of soil amendments with a relatively high variety such as gypsum, basanite, zeolite, chemical amendments, organic additives, a variety of chemical, biological and composite polymers, soiltac, fungi, polyvinyl acetate, vermicompost and cattle manure, biochar, straw mulching and cyanobacteria and bacteria (Behzadfar et al, 2017). The objective of this study was to investigate the influence of bentonite clay and slope gradient on runoff and sediment concentration and some hydraulic Characteristics in the Loess soil using a rainfall simulator. Materials and Methods The experiments were conducted using a rainfall simulator at the Soil Erosion and Conservation Laboratory, Gorgan University of Agricultural Sciences and Natural Resources, Iran. The soil used for the experiments is taken from the surface layer (0-30 cm depth) of loess lands from Golestan province (37° 55ʹ N and 55° 29ʹ E). The soil sample at first was air-dried, thoroughly mixed and then crushed to pass through 10 mm sieve size. Experiments were done as factorial based on completely random design with three replications. The factors were the bentonite clay at four level (0, 2, 5 and 10 % weight) and slope steepness at three level (10, 20 and 30%). In all experiments, each soil sample was put in the flume, then was saturated from the bottom for 24 h. Afterwards, the drainage water was removed out of the tray, and the experiment lasted for 45 min. For each rainfall event, the sediment-laden overland flow was sampled at selected time intervals and volumetrically measured. The sediment-laden overland flow was sampled at several time intervals and the sediment concentration was determined . The sediment in the collected samples was allowed to settle, separated from the water, and dried in an oven at 105 °C for 24 h. The sediment concentration was determined as the ratio of dry sediment mass to sampled runoff volume for each time interval.Different hydraulic parameters including flow depth, shear stress, stream power, and unit stream power were measured.Results and Discussion The result showed that the sediment concentration decreased with increasing levels bentonite at all slopes. At 10 % slope steepness, the mean sediment concentration varied 32.48 in the control treatment to 24.67 kg m-3 at level 3 bentonite treatment. At 30% slope the corresponding value were 474.52 and 224.14 kg m-3. Therefore, with increasing slope steepness the sediment concentration increased. Totally, the use of bentonite at level 10 % weight could decrease 46% of sediment concentration in comparison with control treatment. Defersha and Melesse (2012) found that rain intensity and slope gradient had significant influences on sediment concentration. Slope gradient is important as more soil particles are splashed down-slope than up-slope (Dunne et al. 2010; Grismer 2012). According to Fig. 2, the obtained flow depth was 1.92×10−4, 1.92×10−4, 1.92×10−4 and 1.92×10−4 m for 0, 2, 5, 10% clay treatment, respectively. Also, the depth flow ranged from 3.6×10− 4 to 1.96×10−4 m on 10 to 30 % slopes. Totally, the depth of flow decreased with increasing slope steepness for all treatments. In fact, due to higher flow velocities at steeper slopes, shallower flow depths were achieved. Statistical analysis (Table 2) confirmed a significant positive main effects of application levels of bentonite and slope on shear stress, power flow and unit power flow. The clay treatment showed significant reductions ranging from 2 to 50% compared to the control treatment for all slopes. Unit stream power varied from 0.0084 to 0.0095 ms-1, 0.0176 to 0.0241 ms-1 and 0.030 to 0.057 ms-1 for 10, 20 and 30 % slope, respectively. Totally, with increasing slope steepness, all the hydraulic parameters, except flow depth, increased. While with increasing percentage of bentonite clay, shear stress and depth flow and stream power, decreased. Consequently, the maximum values were observed at the steepest slope (30 %) and control treatment (0%). Conclusion Based on the results obtained during the present study, it can be concluded that the bentonite can be considered as an effective modifier of soil physicochemical properties leading to better performance in soil and water conservation in loess lands. Keywords: Bentonite, Simulator Rain, Slope, Sediment Concentration, Hydraulic Characteristics
Research Paper
Amir Parnian; Hossein Beyrami; Kianoush Behrahi
Abstract
Introduction lack of water and soil salinization are two main threats to the sustainability of agriculture, especially in arid and semi-arid areas same as most parts of Iran. High evaporation in arid and semi-arid regions drive the down-to-up salt movement into the soil profiles and led the soil to salinization. ...
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Introduction lack of water and soil salinization are two main threats to the sustainability of agriculture, especially in arid and semi-arid areas same as most parts of Iran. High evaporation in arid and semi-arid regions drive the down-to-up salt movement into the soil profiles and led the soil to salinization. Soil salinity reduces plant production through many ways like reducing water and nutrient uptake, ion toxicity, change in soil microbial activity, carbon and nitrogen ecological cycle disruption, etc. There are many ways to control the soil salinity and preserve soil water by application of mulch is one of them. Actually the use of mulch on soil in agriculture is mainly to limit evaporation, improve water use efficiency, and weed control. Many tupes of mulch are using to control the soil evaporation such as tephra, sand, plastic, wheat straw, geotextile, etc. Organic mulches have two main disadvantages, the ecological problem and, biological pollution for agricultural areas. More than one million tons of sugarcane bagasse produce in the Khuzestan province of Iran as the agricultural waste. And composting is a proper way to reduce the bad effects of raw organic material. This study examined a soil organic mulch, produced by composted sugarcane bagasse, in Jofeir area haloculture pilot in Khuzestan province. Materials and Methods. This study, conducted in the southwest of Khuzestan province, Iran. The mean temperature during the experiment was 44 ± 2 ᵒC and the relative humidity was 65 ± 3%. The composted sugarcane mulch in 4 different thicknesses of 0.5, 1, 2 and, 0 (control) cm with 3 replicas applied on 2.5 liters of the local silt-clay-loam soil. The micro-lysimeters were 3 liters PVC pots which have heat-insulated and fill with the soil in 25 cm depth. In addition, The weight of the pots were measured at 10:00, 12:00, 14:00, 16:00, and 18:00 houres after the soil saturation. Before and after the experiment soil EC (1:2), bioavailable B concentration, saturation extracts Na concentration, and exchangeable sodium percentage (ESP) of the top 5 cm of the pots was examined. The experiment re-conducted in 5 continuous days and Identification of significant differences was performed using one-way ANOVA, in which p < 0.05 is considered significant in differences. Statistical analysis was performed with the Microsoft Excel 2010 and SPSS Version 16.Results and DiscussionResults showed the significant difference between treatments with and without soil mulch in available water loss. The lowest water loss was belonging to the treatment with 2 cm (198.6 g of water/pot) of sugarcane composted mulch. The non-mulched soil had the highest evaporation amount (407.7 g of water/pot). water loss percentage showed the same trend and reduction with increasing in the sugarcane composted mulch thickness. Which with 2 cm of the mulch the moisture loss percentage calculated about 9.8 % and it near half of the value for the control (no-mulched soil) one. This mulch able to increase the available water for plant uses. Salts, B, and Na accumulation in surface soil appeared due to the evaporation process and mulch prevents it. As the results represented, with increasing the sugarcane composted mulch thickness, EC rising was slow. The EC increase in surface section of the non-mulched soil was high (20.5 dS/m) and the final EC were 41, 32, 25.5, 22 dS/m respectively in 0, 0.5, 1, and 2 cm of the mulch thickness treatments. This effect of sugarcane composted mulch could save the plant roots from salinity effects such as high Na, B and ESP. Also, it may play a positive role in water preservation in horticulture and green space. According to the composting process, this mulch has less ecological adverse effect than other organic raw materials. On the other hand, it able to release carbon and nutrients to enhance soil biological activity which would help plants to grow well.Conclusion Results showed increasing in the water losses and salinity accumulation in the soil surface of the treatments with decresing the mulch thickness. Also, the same trend was observed for bioavailable B concentration, saturation extract Na concentration, and ESP of the soil surface. Evaporation and, as the result salinization of the soil surface, decreased by the time but, the salt transport was very fast and the high considerable amount moved to the top
Research Paper
Kamran Azizi; Shamsollah Ayoubi; Kamal Nabiollahi
Abstract
Introduction: The parent material and geology have a significant contribution to heavy metal contents and magnetic susceptibility in soils. Magnetic susceptibility is known as the extent of a material’s impact on the magnetic field, which depends on the concentration and the type of magnetic minerals ...
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Introduction: The parent material and geology have a significant contribution to heavy metal contents and magnetic susceptibility in soils. Magnetic susceptibility is known as the extent of a material’s impact on the magnetic field, which depends on the concentration and the type of magnetic minerals in the soil. Magnetic susceptibility measurement is fast, easy, economically convenient, and non-destructive. Mass magnetic susceptibility and frequency-dependent magnetic susceptibility are among the conventionally used parameters. The type of land use is among the main factors influencing magnetic susceptibility distribution in soil. Besides, soil magnetic susceptibility is affected by slope position and different soil properties such as soil organic matter and carbonates. A variety of relationships have been observed between heavy metal concentrations and magnetic susceptibility across various types of soil, parent material and climatic regimes. Generally, magnetic properties have positively correlated with the type and concentration of magnetic minerals as well as the particle size of soil fractions. Besides, magnetic susceptibility has a weak negative correlation with diamagnetic components such as quartz, gypsum, calcite, and organic materials. The main objectives of this study were to i) determine the relationships between magnetic susceptibility (MS) and concentration of some heavy metals such as copper, iron, zinc, and manganese in the surface soils and ii) explore the impacts of land use and geomorphological units on the variability of heavy metals and MS in a semi-arid region in the west of Iran.Materials and Methods: The present study was conducted in Kurdistan province located in western Iran, the area is about 110,000 ha and mean altitude of 2277m above sea level. The area has an average annual temperature of 10.20 °C and an average annual rainfall of 369.8 mm, which dominantly occurs in spring and winter. Besides, the area has soil moisture and temperature regimes of Xeric and Mesic, respectively. The lithological setting of the studied area includes reddish of sandy marls and marl sandstone, river deposits, alluvium-cultivated land, and granite. The studied area was divided into different parts in terms of geomorphology and land use. Soil sampling was done using the stratified random sampling approach. A total of 347 samples were collected from the surface layers (0-30 cm depth) of the studied area. Magnetic susceptibility at both high and low frequencies was measured using a Bartington MS2 dual-frequency sensor. The amounts of all the selected heavy metals including iron, zinc, manganese, copper, and nickel were measured using atomic absorption spectrophotometer. Soil particle sizes, acidity, SOC, CCE and electrical conductivity were measured in all soil samples. The concentration factor and Tomlinson’s Pollution Load Index were calculated. The Spearman correlation coefficient was used to examine the correlation between different parameters. The analysis of variance was used to evaluate the effects of geomorphology and land use on heavy metals and magnetic susceptibility. Spatial analysis was done conducted for some variables (Fe, Mn, Zn, Ni, Cu, and χlf) and the map of variables were created in ArcGIS v.13 software.Results and Discussion: The results showed that the positive significant correlations were observed between heavy metals and silt content and negative significant correlations were observed between heavy metals and sand content. Fine soil fraction compared with coarse fraction has the higher specific surfaces and more susceptible to attract heavy metals. Moreover, positive and significant correlations were obtained between the SOC and heavy metals across various land use types and geomorphic units. Organic matters have a high cation exchange capacity, therefore they adsorb heavy metals and hold them on their surfaces. pH and CCE showed negative and significant correlations with heavy metals and magnetic susceptibility. The positive correlation between heavy metals and magnetic susceptibility in agricultural land, piedmont, and river plains units observed. Also, PLI and CF have a positive correlation with magnetic susceptibility. The t-test showed that a significant difference between agricultural lands and non-agricultural land types and ANOVA results in various geomorphic units of the study area indicated that the magnetic susceptibility between piedmont and mountainous areas were significantly different. Conclusion: Results indicated a significant correlation between magnetic susceptibility and heavy metals. Besides, the magnetic properties of the soil are influenced by its physical and chemical properties that have large impacts on reducing or improving its magnetic field. Significant differences were observed between agricultural lands and non-agricultural lands as well as mountainous and piedmont areas that had different parent materials. These results indicate the great impact of parent materials constituting the soil on the absence or presence of diamagnetism in the region.
Research Paper
najmeh salari ardsiri; Majid Hejazi-Mehrizi; hormazd naghavi; rabi Behrooz; Majid Fekri
Abstract
Introduction providing the food needed by the world's ever growing population has led to changes in cultivated areas, water resources, and the overuse of chemical fertilizers and consequent environmental pollution. Providing essential nutrients to the plant is one of the most important factors related ...
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Introduction providing the food needed by the world's ever growing population has led to changes in cultivated areas, water resources, and the overuse of chemical fertilizers and consequent environmental pollution. Providing essential nutrients to the plant is one of the most important factors related to the optimum production of agricultural crops. In recent years, most of essential nutrients are provided through the natural fertility of the soil and chemical fertilizers. Today, one of the most important ways to increase soil fertility is the use of fertilizers. Consistent and excessive use of fertilizers such as nitrogen and phosphorus (in the form of ammonium salts, urea, nitrate or phosphate compounds) in recent years has caused problems in the agriculture and environment. In recent years, the efficiency of application of nitrogen, phosphate and potash fertilizers has been about 30-35, 18-20 and 35-40-40, respectively. This indicates that a large part of the fertilizer used remains in the soil or enters the aquatic ecosystems and negatively affects the natural balance and biodiversity of agricultural lands. Accordingly, to overcome these problems, it is necessary to use solutions such as better water and fertilizer management, change in the structure of fertilizers and the use of new technologies. One of the effective methods to overcome the problems of low efficiency of chemical fertilizers is to develop the controlled release fertilizers. Slow-release fertilizers can be a good way to overcome the problems expressed by common chemical fertilizers. Release control fertilizers are usually prepared using the coating method and reducing the solubility of water-soluble fertilizers by creating a physical barrier. The biggest problem with slow release fertilizers is their high production cost. Therefore, it is necessary that the fertilizers covering chemical fertilizers be economical and compatible with the environment and have desirable coating properties. Nanocomposites are among the polymer coatings that have received much attention in recent research. Among the many materials used to form nanocomposites, polysaccharides such as cellulose, starch for economic reasons, biocompatibility, non-toxic and biodegradable are widely used compared to synthetic polymers. Despite many studies in the field of fertilizer production, the use of slow release fertilizers as a source of required nutrients and also the use of hydrophilic and hydrophobic polymers such as pure cellulose compounds with conventional fertilizers have not been studied. The need for this research is to use cellulose from agricultural waste in slow release of chemical fertilizers in order to increase the efficiency of fertilizers, prevent its overuse in agriculture, and also waste agricultural waste around orchards. In this study, cellulose compounds were extracted from paper, palm and pistachio branch and these cellulose compounds were then used to slow the release of urea fertilizers.Materials and Methods First, the sufficient amounts of pruned wastes from branch of palm, pistachio, and paper waste, were collected from agricultural regions in Kerman Province; then they were transferred to the laboratory of Kerman Agricultural Research Center. After washing and drying, the samples were ground. In the next step, 10 g of each of the air-dried cellulosic sources was passed through a 60-mesh sieve in an Erlenmeyer flask with 200 ml of 1% NaOH solution for 1 h. Then, it was entirely washed with distilled water and the resulting contents in the Erlenmeyer flask were re-boiled along with a mixture containing 300 ml of 80% acetic acid plus 30 ml of 67% nitric acid for 30 min at 120°C. At the end of the reaction time and partial cooling of the mixture, the cold distilled water was added to the reaction mixture and the resulting cellulose pastes were then washed thoroughly with distilled water until reaching the neutral pH. At the end, the samples were air-dried. Finally, the cellulose samples were washed with distilled water and air dried. In the second stage, slow release of urea fertilizer with cellulose from palm wastes in a ratio of 1 to 2 (fertilizer to cellulose) was made and they were made in the form of small tablets. Nitrogen release kinetics from these fertilizers in soil up to 90 days were measured and kinetic equations were also investigated.Results and Discussion After cellulose extraction of wastes, FTIR device was used to identify the extracted celluloses and compare them with Sigma Aldrich pure cellulose. The peaks obtained from the FTIR apparatus were similar to the pure cellulose peaks. The yield of extracted cellulose in the form of paper waste was 70%> palm branch 33%> branch of pistachio 28%. In the second stage, the extracted cellulose was used to cover urea fertilizer in a ratio of 1 to 2 (urea fertilizer to cellulose) and the desired fertilizer was made in the form of small tablets with diameter of 0.5 cm and height of 2 cm. The SEM scanning electron microscope was used to study the structure of the manure. Microscopic images showed that the urea fertilizer placed as white spherical particles around the cellulose rod particles, indicating that the urea fertilizer particles adhered to the cellulose particles without any adhesive. The FTIR diagram of the fertilizer showed that the shift of the diagram upwards at the common wavelengths in urea and pure cellulose and a strong physical bond is established between them. Nitrogen release kinetics for all treatments that were less than pure urea fertilizer and significant differences observed between treatments and pistachio branch cellulose caused a slower release of urea fertilizer. The kinetic equation of the power function was selected as the best model for fitting the kinetic data. The studied wastes in this study have a high potential for producing pure cellulose to slow the release of urea fertilizer.
Research Paper
Farzaneh Bandehelahi; Isa Esfandiarpour-Boroujeni; Alireza Karimi; Mohammad Hady Farpoor; Zohreh Mosleh; Morteza Fattahi
Abstract
Introduction Landscape represents a large portion of land/terrain that is either formed by a repetition of similar or dissimilar relief/molding types or an association of dissimilar relief/molding types (e.g., valley, piedmont, mountain, etc.). It is usually affected by a set of natural (e.g., climate, ...
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Introduction Landscape represents a large portion of land/terrain that is either formed by a repetition of similar or dissimilar relief/molding types or an association of dissimilar relief/molding types (e.g., valley, piedmont, mountain, etc.). It is usually affected by a set of natural (e.g., climate, organisms, parent material, topography, time, erosion, sedimentation, etc.) and/or artificial (e.g., artifacts) factors. Soil is one of the most important components of landscape that is affected by various factors such as water and wind. Aeolian or alluvial sediments (from seasonal rivers) in arid areas cause the formation of different landforms and change the landscapes in these areas. Therefore, the study of geoforms in arid regions can lead to a better understanding of geomorphological processes and soil change in these areas. There are various methods, including soil micromorphology and clay mineralogy, to understand the alteration of landscapes and the soils change on them. The aim of this study was to investigate the physical and chemical properties, clay mineralogy and micromorphology of soils in various geomorphic units of Davaran Region, Rafsanjan.Materials and Methods Seven dominant geomorphic units (geoforms) of the region, including pediment, margin of fan and cultivated clay flat, alluvial fan, desert pavement, margin of pediment and sand sheet, active drainage, margin of fan and uncultivated clay flat were selected using Google Earth images and field studies. Nineteen pedons were excavated and described in the geomorphic units. After selecting a representative pedon in each of the geoforms, their genetic horizons were sampled. Besides, in order to conduct soil micromorphology studies, undisterbed and oriented samples were collected from selected horizons. After transferring the samples to the laboratory, their physical and chemical properties were measured using standard methods. In addition, clay mineralogy studies were performed by X-ray diffraction method and micromorphological studies were done using a petrographic microscope. Finally, soil classification was performed based on both Soil Taxonomy (2014) and WRB (2015) systems.Results and Discussion Results showed that gypsification and calcification are the dominant soil forming processes in the studied region, which have led to the formation of Gypsic and Calcic horizons. This has placed the soils in the Gypsids and Calcids suborders based on the Soil Taxonomy system and the Gypsisols and Calcisols reference soil groups according to WRB system. The representative pedon in the margin of fan and cultivated clay flat (pedon 2) geoform lacks a salic horizon based on the Soil Taxonomy; while it is in the Solonchak reference soil group of the WRB. Also, the presence of argillic horizon in the representative pedon of the margin of fan and uncultivated clay flat geoform (pedon 7) indicates presence of a more humid paleoclimate in the history of the region. The results of clay mineralogy showed that the predominant minerals in the region include chlorite, illite, kaolinite, and smectite. The illite, chlorite, and kaolinite are inherited from papent materials of the soils, and the smectite has a transformation origin (from palygorskite and illite). Addition of this mineral by aeolian or alluvial sediments could not also be neglected. The micromorphological results indicated that the soil pores were mainly chamber. The presence of carbonates and gypsum in the studied soils has caused that the b-fabric in the most horizons to be Calcitic Gypsic Crystallitic. Gypsum was observed in the form of vermicular, lenticular, interlocked gypsum plates and subhedral shapes. Other pedofeatures in the studied soils include calcite nodule and limestone.Conclusion The simultaneous presence of aeolian and alluvial sediments in the different geoforms of Davaran region has caused the formation of stratified soils. Existence of dry climate and lack of significant vegetation in the region from one hand, and the addition of different sedimentary layers at different times (which causes soil rejuvination) on the other hand, has caused that the soils of the region, in general, not to be highly developed. As a result, few differences were observed among soils in different geoforms. Comparing the results of two soil classification systems for the studied soils showed that in general there is a relatively good correlation between them. Totally, the role of climate and parent material in alteration of the studied soils is evident; so that the physical and chemical properties, clay mineralogy and micromorphology of soils in different geoforms have been affected.
Research Paper
Zahra Rezaee; Mojtaba Norouzi masir; Abdolamir Moezzi
Abstract
Introduction:Organic matter based on their composition and the C/N ratio can have different effects on nutrient bioavailability, concentration and uptake in soil and plant. Beside that, organic fertilizer can increase the yield of different agricultural products and pave the wey for emergence of sustainable ...
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Introduction:Organic matter based on their composition and the C/N ratio can have different effects on nutrient bioavailability, concentration and uptake in soil and plant. Beside that, organic fertilizer can increase the yield of different agricultural products and pave the wey for emergence of sustainable agricultural . Organic matter is relatively low in majority of soils in Iran, and continuous use of chemical fertilizer would create environmental hazards . Zinc deficiency is a worldwide nutritional constraint in crop production particularly in cereals growing on calcareous soils .Materials and methods:This research was conducted to investigate the effects of organic fertilizers such as bagasse, compost and biochar and chemical fertilizer ZnSo4 on yield of wheat and concentration and uptake of Zn in wheat ,a study based on randomized complete block design with 3 replications was conducted in Greenhouse Faculty of Agriculturar of Shahid Chamran University of Ahvaz during the years1395-96. Treatments included:1-control ,2- ZnSo4 , 3-Bagasse 4- Biochar 5- compost. Some Physical and chemical properties were determined using standard methods (table1).some basic properties of bagasse , compost and biochar were also determined (table 2). after the experiment ,soil and plant properties such as pH, organic matter content(OM), available Zn in soil. and yield , yield components and concentration and uptake of Zn in wheat were determined in samples.After seed ripening grain , yield and component yield were measured from the total pot of each treatment.Statisical analysis of the data was performed using SAS software and comporision using Toki method was also performed.Results: the intial soil was clay loam with organic matter content( om=0.79).Results showed that the treatments had significant effect (p≤ 0.01) on percentage of organic carbon, organic matter, the availability of Zn and pH of soil . Also content of soil micro element affected by treatments and amount of these parameters were increased by using of organic fertilizers .Increase the organic matter in soil by compost improved a must of chemical peroperties and Increase concentration nutrient element in soil. Results showed that pH in the control decreased significantly from 7.74 of soil to 7.53 of soil in the compost. Results showed that the available Zn in the control increased significantly from 0.5 mg kg-1 of soil to 0.71 mg kg-1 of soil in the compost.The results of the experiment showed that all treatments except bagsse increased factors wheat yield . Compost showed greatest yield and bagasse the lowest yield in the the wheat root, grain and shoots (compared to the control). The highest grain yield was obtained from the application of compost. The maximum amount of chlorophylls (a, b, total and SPAD), with application compost. The highest Plant height was obtained from the application of biochar. The results showed that the highest and the lowest of va lue concentration and uptake of Zn in wheat to compos and bagasse respectivity. The maximum amount of chlorophylls (a, b, total and SPAD), with application compost. The highest Plant height was obtained from the application of biochar. The results showed that the highest and the lowest of va lue concentration and uptake of Zn in wheat to compos and bagasse respectivity. Discussion:The obtained result highlight the increased effects of compost on yield and yield components and Zn uptake change in wheat, also in comparison to other treatments, it emphasizes ore on the soil though they were useful too. Therefore, it can be concluded that applying organic fertilizers especially composted form would have, useful effects on plant growth and increasing the concentration of Zn of wheat .The obtained result highlight the increased effects of compost on yield and yield components and Zn uptake change in wheat, also in comparison to other treatments, it emphasizes ore on the soil though they were useful too. Therefore, it can be concluded that applying organic fertilizers especially composted form would have, useful effects on plant growth and increasing the concentration of Zn of wheat .The obtained result highlight the increased effects of compost on yield and yield components and Zn uptake change in wheat, also in comparison to other treatments, it emphasizes ore on the soil though they were useful too. Therefore, it can be concluded that applying organic fertilizers especially composted form would have, useful effects on plant growth and increasing the concentration of Zn of wheat .
