Showing 6 results for Enayati
K. Enayati, M.j. Rousta, A. Vakili,
Volume 15, Issue 56 (sumer 2011)
Abstract
Soil structure and aggregate stability affect soil erodibility. There is a necessity for increasing aggregate stability against erosive factors such as wind and water. This study was conducted on surface soil samples (0-20cm) collected from agricultural land susceptible to erosion located in Chahoo, southeast of Fars province. The experimental design was CRD with 10 treatments and was replicated 3 times as follows: control plot (without addition of soil amendments), pure gypsum, chopped wheat straw, farm yard manure, gypsum+wheat straw, gypsum+ farm yard manure (1% w/w), cement at levels (0.3% w/w), (0.6% w/w), (0.9% w/w), gypsum +cement (0.9% w/w). After one, four and seven months, the amounts of soil aggregates in 53-4000 µm sizes were determined by wet sieving and MWD was calculated. The results of aggregate size distribution in every stage of the experiment showed that application of farm yard manure and wheat straw separately or in combination with gypsum through reduction in aggregates with diameters of <106 µm has caused an increase in aggregates with diameter of >106 µm. Based on the results of this research, the effect of these treatments, which increased MWD of the aggregate, results from the amount of aggregates with diameters larger than 1000 µm. According to the results of this study, it is suggested that these treatments be considered suitable to increase the stability of sensitive silt loam soils.
M. Farzadian, S. Hojati, Gh. A. Sayyad , N. Enayatizamir,
Volume 19, Issue 72 (summer 2015)
Abstract
One of the major problems associated with petroleum-contaminated soils is water repellency, especially in arid regions of the world. Hence, a variety of methods such as clay addition has been proposed to improve the hydrophobicity of soils. This research was conducted to evaluate the influence of zeolite application on water repellency of an oil-contaminated soil from Khuzestan Province under various treatments including initial soil moisture content (0, 10, 20, and 30 weight %), the amount of applied zeolite (2, 4 and 8 weight %), size (25-53 and <2 μm), and exchangeable cation (Sodium and Calcium). The hydrophobicity of soil sample was determined using Water Drop Penetration Time (WDPT) method. The results showed that by increasing the amount of applied mineral WDPT decreased, where the application of 2 percent of zeolite led to the reduction of WDPT by about 27 percent less than the control. The results also indicated that soils treated with sodium-saturated zeolite had less WDPT than the calcium-treated samples, where the average of WDPT in sodium and calcium treatments decreased by 23% and 5% compared with the control, respectively. The initial moisture content of 30 percent showed the best performance with the decreasing WDPT of about 67 percent. Furthermore, the effect of mineral particle sizes showed a meaningless reduction in WDPT.
B. Rezaeiniko, N. Enayatizamir, M. Norouzi Masir,
Volume 22, Issue 4 (Winter 2018)
Abstract
Zinc is essential micronutrients for plants. This element improves plant growth and yield and plays a role in the metabolism of carbohydrates. Zinc deficiency in soils and Iranian crops is possible due to numerous reasons such as calcareous soils, excessive use of phosphorus fertilizers and unbalanced fertilizer use. The effect of zinc solubilizing bacteria on some wheat properties was considered as a factorial experiment in greenhouse conditions based on a completely randomized design. Treatments consisted of four levels of bacteria comprising B1 (control), B2 (Bacillus megaterium), B3 (Enterobacter cloacae) and B4 (consortium of both bacterium), and ZnSO4 fertilizer at three levels including Zn0 (control), Zn20 (20 Kg/ha) and Zn40 (40 kg/ha). During the experiment, some parameters such as plant height and chlorophyll index were measured. At the end of the cultivation period, soil available zinc, dry weight of root and aerial part, and the zinc concentration of the root, shoot and grain were determined. Grain yield and zinc uptake in the grain were also calculated. The results indicated soil exchangeable zinc content was increased significantly (P<0.05) in all bacterial treatments, as compared to the control treatment. The maximum amount of soil exchangeable zinc, grain yield, zinc concentration and uptake in grain were observed in the treatment containing bacteria consortium with the application of 40 kg/ha of zinc sulfate fertilizer, which was followed by the treatment containing Enterobacter cloacae with the application of 40 kg/ha of the zinc sulfate fertilizer. The maximum amount of all measured properties in the treatment containing Enterobacter cloacae and Bacillus megaterium indicated the possibility of applying those bacteria for zinc enrichment in wheat, crop optimal production, and the sustainable agriculture.
N. Enayatizamir, M. Noruzi Masir, A. Ghadamkhanii,
Volume 23, Issue 4 (winter 2019)
Abstract
The soil organic matter plays an important role in increasing agricultural products and various nutrient cycle in the soil due to its effect on the physical, chemical and biological properties of soil. There is, however, little information regarding the effect of growth promoting bacteria on biological indices and different forms of carbon in agricultural soils of the country. Therefore, this study was aimed to investigate the effect of plant growth promoting bacteria on soil respiration, microbial quotient, organic carbon, microbial carbon biomass, permanganate oxidizable carbon, cold water extractable organic C, and hot water extractable organic C under the cultivation of wheat, Chamran cultivar. The experiment was conducted in greenhouse condition as a randomized complete design with 9 replications. Treatments consisted of bacterium inoculation (without inoculation, Enterobacter cloacae Rhizo_33, Enterobacter cloacae Rhizo_R1
and mixof both bacteria). During the experiment, some characteristics such as plant height and chlorophyll index were measured. At the end of the cultivation period, root and aerial part dry weight and grain yield were determined. Biological properties and different forms of carbon in the soil were measured after cultivation. The results indicated the applied plant growth promoting bacteria increased chlorophyll index, height, root and shoot dry weight and grain yield, as compared to the control. The minimum value of pH and the highest amount of each carbon forms were obtained by soil inoculation with different strains of bacteria, as compared to the control. The highest value of organic carbon was observed in the presence of the consortium of both bacteria with 22.7% increase, as compared to the control. The highest amount of microbial carbon biomass was, respectively, measured in the treatments containing consortium of bacteria, Enterobacter cloacae Rhizo_R1, Enterobacter cloacae Rhizo_33 with 87.67, 42 and 26.5% increment, as compared to the control. A positive and significant correlation was observed between cold and hot water extractable organic carbon, dissolved organic carbon and permanganate oxidizable carbon with soil respiration and there was a negative correlation between mentioned properties and the soil pH. The use of microbial inoculants increased the carbon content of the soil, which can play a positive role for improvement of physical and chemical properties of the soil and plant yield.
S. F. Hashemi, R. Zalaghi, N. Enayatizamir,
Volume 26, Issue 1 (Spring 2022)
Abstract
This study investigated the effect of the inoculation of the soil with some phosphorus solubilizing microorganisms (PSM) on inorganic P fractions in sandy soil enriched with inorganic and organic amendments. A factorial experiment arrangement was performed in a completely randomized design with three replications, using two factors: microorganisms (control, Entrobacter cloacae, Brevundimonas, and piriformospora indica) and amendments (control, (5%) apatite, (5%) apatite + (3%) zeolite, (5%) apatite + (1%) molasses). A 60-days incubation was performed after the application of treatments. Inorganic P fractionation and alkaline phosphatase activity of soil were measured at the end of the experiment. Phosphorus distribution in soil was as follow: octacalcium phosphate > apatite P > dicalcium phosphate > Olsen p > aluminium phosphate > iron phosphate. The application of apatite increased all of the P mineral fractions. The application of zeolite-appatie was very effective and although did not increase Olsen P (probably because of the low cation exchange capacity of soil), had a significant effect (p<0.05) on other P forms and caused dicalcium phosphate to increase (69.2%) and apatite P and octaclcium phosphate to decrease (34.8% and 60.0%, respectively) compared to apatite application. Application of molasses resulted in significant increases in dicalcium phosphate and octacalcium phosphate (48.9% and 29.3%, respectively) and decreases in apatite P and Olsen P (62.1% and 63.9%, respectively). Microbial inoculation resulted in a significant increase in Olsen P and dicalcium phosphate and a decrease in octacalcium phosphate and apatite P; showing the ability of these organisms to increase the phosphorus availability. Entrobacter and Piriformospora indica were more effective than Brevundimonas. It seems that microorganisms in different substrates had used different mechanisms; such that in apatite and apatite-molasses treatments microbial inoculation resulted in an increase in alkaline phosphatase activity, but in zeolite-apatite treatment, pH had decreased indicating the organic acid production by microorganisms.
Seyed Masoud Soleimanpour, Omid Rahmati, Samad Shadfar, Maryam Enayati,
Volume 30, Issue 1 (spring 2026)
Abstract
Gully erosion is one of the most important types of water erosion. Since the amount of soil loss due to this erosion is directly related to environmental factors, the amount of soil loss due to each gully can be modeled based on environmental conditions. According to the high ability of machine learning models based on artificial intelligence to analyze environmental information, in addition to determining soil loss due to gully erosion, modeling has been carried out using two random forest models, and artificial neural networks and evaluating their efficiency in the Mahurmilati watershed located in the southwest of Fars province in this study. The dimensional parameters of 70 gullies were measured over four years (2021-2024), and the volume and weight of soil lost were calculated. 15 environmental factors were selected as predictive variables, and modeling was performed with a cross-validation approach using these two models, and the accuracy of the models was evaluated using quantitative criteria. The amount of soil loss in gullies during the study period was 15300.94 tons. The accuracy evaluation of the models showed that the random forest model had better performance based on the coefficient of determination (R2=0.66-0.73). Also, this model had the lowest value in terms of the RSR error index evaluation criterion (RSR=0.66-1.03) and the highest accuracy. In terms of the fit evaluation index (D), the random forest model also had the highest fit between the observational and forecast data and had the highest value of this index (D=0.83), and therefore, it was introduced as the superior model for predicting soil loss due to gully erosion in this watershed.
