Showing 7 results for Vahedi
N Vahedi, M Mazaheri Tehrani, F Shahidi,
Volume 13, Issue 48 (7-2009)
Abstract
In this study, the effect of “Osmodehydrofrozen” fruit addition on sensory, physical, chemical and microbiological properties of concentrated yoghurt and its quality during storage was evaluated. This research was done in two stages. At the first stage, fruit percentage, type and addition time (before and after fermentation) was determined. The results indicated yoghurts containing 10% apple or 13% strawberry, which was added before fermentation had a better quality. Because of high osmotic activity of apple, the synersis was lower in apple yoghurt in comparison with strawberry yoghurt. According to osmotic activity of both fruits, the synersis value was much lower than that of fruit yoghurts, which contained untreated fruits. Taste value was higher in strawberry yoghurt and texture and mouth feel values were higher at low percentages of fruit. The results of the second stage (quality evaluation during storage) indicated that storage had a significant effect on pH, acidity, synersis, taste and texture (P<0.05). In samples which contained apple, coli forms disappeared after 7 days of storage. In samples that contained strawberry, coli forms disappeared after 7 days of storage.
M. Bahreini Touhan, E. Dordipour, S. A. Movahedi Naeini,
Volume 14, Issue 53 (fall 2010)
Abstract
Kinetical study on non-exchangeable potassium (NEK) release is necessary for management, optimum use of soil resources, availability and supplying power of potassium. Information about NEK release rate in Golestan soils is limited. The aim of this study was to investigate the NEK release of saturated soil sample by calcium using acid citric and CaCl2 extractants from 2 to 1844 h duration in 12 dominant soil series in Golestan province. Different soils indicated various responses to continuous extraction. The rate of K released in different soils was lower in CaCl2 than that of Citric acid. Potassium release was faster in earlier periods of the extraction in all soils followed by a lower release rate. Due to high coefficient of determination and low value of the standard error of the estimate, the NEK release kinetic by citric acid and CaCl2 were well described by Elovich and Parabolic diffusion equations and Power, First order and Elovich equations, respectively. Therefore, NEK release rate was controlled by K diffusion from weathered surface of soil minerals.
M. Hosseini, S. A. Movahedi-Neeni, M. Zeraat Pishe,
Volume 18, Issue 68 (summer 2014)
Abstract
Effects of five various tillage systems on soil porosity, volumetric water content, diurnal and nocturnal soil temperatures, plant water uptake and dry matter yield was investigated using a completely randomized design with five treatments and four replications in Gorgan University of Agricultural Sciences and Natural Resources research farm located in Seyed-Miran during 2009-2010 growing season. Tillage systems were: moldboard plough followed by one discing (20-25 cm) rototiller (12-17 cm) double disc (8-10 cm) Chisel plow (25-30 cm) No-tillage. Results show that during all stages of wheat growth, the highest and the lowest soil porosities at 0-8 cm depth were obtained by moldboard plough and No-tillage treatments respectively. For all stages except before tillering and harvest, the highest soil porosity obtained by moldboard treatment at 8-16 cm depth. Increasing tillage intensity increased those porosity that keep water in potentials greater than -5 and those in potentials less than -15 bar. No-tillage and moldboard induced the highest and the lowest soil temperatures respectively before earring stage. Tillage intensification, increased soil porosity and root density. More roots reduced soil water content in response to increased water uptake by wheat, resulting greater dry matter accumulation.
R. Vahedi, M. H. Rasouli Sadaghiani, M. Barin,
Volume 23, Issue 1 (Spring 2019)
Abstract
The pyrolysis of fruit trees Pruning waste to be converted to biochar with microbial inoculation is a strategy improving the biological properties in calcareous soils. In order to investigate the biochar effect on some soil biological properties of the soil in the presence of microorganisms, a factorial experiment was carried out in a completely randomized design in the rhizobox under greenhouse condition. The factors included organic matter (pruning waste biochar and control), microbial inoculation (arbuscular mycorrhizal fungi and plant growth promoting rhizobacteria) and soil (rhizosphere and non-rhizosphere). After the end of the wheat plant growth period, microbial respiration (BR), Substrate-induced respiration (SIR), microbial biomass carbon (MBC), microbial biomass phosphorus (MBP), acid phosphatase (ACP) and alkaline phosphatase (ALP) enzymes in the rhizosphere soil and non-rhizosphere soil were determined. The results showed that the biochar and microbial inoculation application increased BR, SIR, MBC, MBP and ALP and decreased ACP, as compared to the control. So, the highest increase in the value of BR, SIR and MBC was related to mycorrhizal inoculation with biochar. An increase of 2.67 fold of ACP activity was observed in the treatment of bacterial inoculation with Biochar, as compared to the control treatment. Also, pruning waste biochar increased the amounts of MBC, MBP and ALP by 45.62%, 56.22% and 62.6% in the rhizosphere soil rather than non-rhizosphere soil, respectively. Microbial inoculation led to the increase of 1.31 and 1.41 folds by MBP and ACP in the rhizosphere soil, as compared with non-rhizosphere soil. Bacterial inoculation in the rhizosphere soil increased the ACP enzyme activity (28.31%), as compared with non-rhizosphere soil. It could be concluded that application of biochar in the conditions of microbial inoculation improved the soil biological properties.
R. Vahedi, M. H. Rasoili-Sadaghiani,
Volume 23, Issue 4 (winter 2020)
Abstract
Synergistic relationships between mycorrhizal fungi (AMF) and organic compounds affect the mobility of the micronutrient elements in the rhizosphere and improve their bioavailability. In order to evaluate the effect of biochar and pruning waste compost of apple and grape trees, as well as AMF, on micronutrient bioavailability in calcareous soil at the wheat rhizosphere, an experiment was carried out in a completely randomized design under greenhouse conditions in a rhizobox study. Some factors including the organic sourses (pruning waste biochar, pruning waste compost and control), microbial inoculation (AMF and no inoculation) were considered. At the end of the growth period, Organic matter (OM) content and bioavailability of micronutrients including iron (Fe), Zinc (Zn), Copper (Cu) and Manganese (Mn) in the rhizosphere and their uptake by wheat plant were determined. The results indicated that OM, Fe, Zn, Mn and Cu were significantly increased in the rhizosphere soil under the influence of organic sources and mycorrhizal inoculation. Furthermore, biochar application in the mycorrhizal tratment resulted in 74.73% and 19.28% increase in Fe and Mn, as compared to non-inoculated conditions, in rhizosphere. The presence of mycorrhizal fungi increased the bioavailability of 94.66% and 29.54% Zn and Cu in the compost treatment, as compared to non-inoculated ones. Application of organic sources and mycorrhizal inoculation increased the micronutrient uptake and plant dry weight.
M. H. Rasouli-Sadaghiani, R. Ebrahimi Karimabad, R. Vahedi,
Volume 24, Issue 3 (Fall 2020)
Abstract
In order to investigate P acquisition efficiency (PACE) and P utilization efficiency (PUTE) of the corn in the presence of phosphate-solubilizing microorganisms (PSMs), a factorial experiment was carried out in a completely randomized design in the greenhouse. The factors were including P sources (tricalcium phosphate (TCP) and rock phosphate (RP)) and microbial inoculation (control, soluble P as KH2PO4 (Ps), inoculation with bacteria (PSB), inoculation with fungi (PSF), co-inoculation of PSB + PSF). At the end of growth period, plant dry weight and P content in plant and soil available-P were measured and then PACE, PUTE and phosphorus efficiency (PE) indices were calculated. The results showed that, the interaction of phosphate source and microbial inoculation was significant with respect to shoot P content, soil P, PUTE and PE. PSF-TCP treatment increased 7 times shoot phosphorus content compared to cont-RP treatment. PUTE in Cont-TCP treatment was 2.35 times higher than the TCP-PS. The inoculation of PSF increased the PACE 1.61 times compared to co-inoculation of PSB + PSF tretment. Also, the highest PE index (99%) was obtained from SF-TCP treatment. In general, in calcareous soils with low P availability, inoculation of PSM with insoluble phosphorus sources can meet the phosphate needs of the plant.
M. Mehri, M. Hashemy, S. Javadi, M. Movahedinia,
Volume 27, Issue 3 (Fall 2023)
Abstract
Rapid urbanization is responsible for impervious area increases and more runoff generation in urbanized catchments. Higher runoff volume in urbanized catchments leads to higher flood risk. One of the methods of runoff management is low impact development (LID). Bio-retention cell (BRC) is one of the infiltration-based LID practices that allows restoring the pre-development hydrologic cycle. However, the overall hydrologic performance of BRCs can vary depending on different urban environments. In this study, the hydrologic performance of BRC in terms of runoff and flood reduction was investigated in a highly urbanized area in the east of Tehran, Iran. The SWMM model was used to evaluate the performance of BRC. The results showed that BRC for rainfall with a return period of 2 to 50 years reduced the total runoff volume by 76.2% to 70.2% and the peak discharge by 65.9% to 36.4%, respectively. Also, for rainfall with a return period of 2 to 50 years, BRC resulted in 15.2% to 27.5% infiltration of rainfall in the study area, respectively. This study demonstrates that BRC can help restore the natural hydrologic cycle of urbanized catchments by reducing runoff and increasing infiltration.
