Showing 40 results for شیر
Z. Karimi , M. Rahemi,
Volume 12, Issue 45 (10-2008)
Abstract
Pathogens are the most important factors inducing postharvest losses on citrus fruit. Experiments were conducted as a CRD with 4 replications on sweet lime (Citrus limetta) and Valencia orange (Citrus sinensis) in 2003 and 2004. Treatments were pure essential oils of clove and thyme and in 25% ethanol solution at concentrations of 0.1, 0.3 and 0.5% and imazalil (2 ml/l). Results indicated that in the first year, pure essential oils of clove and thyme reduced the decay percentage of blue mold of Valencia orange fruit from 90 % (control) to 0 and 12.5 %, respectively. Pure essential oils of clove and thyme reduced the decay percentage of sweet lime in the first year of experiment from 95 % (control) to 0 and 6 %, respectively. In the second year, with the same treatments decay percentage of blue mold was reduced from 90 % (control) to 0. Solutions of 0.1, 0.3 and 0.5 % of clove and thyme oil extracts in 25 % ethanol solution reduced decay percentage of sweet lime fruits form 85 % (control) to 65, 41 and 26 % for thyme oil and to 60, 30 and 22.5 % for clove oil. Comparison of pure clove and thyme oil extract with imazalil showed that pure clove and thyme oil extracts were not significantly different with fungicide treatment. Treatments of clove and thyme oils in 25 % ethanol treatment were not as effective as fungicide.
M. Alichi, P. Shishehbor, M.s. Mossadegh, E. Soleiman Nejadian,
Volume 12, Issue 45 (10-2008)
Abstract
In a study of aphids and their parasitoids in wheat fields of Shiraz region, the species composition, distribution and seasonal dynamics of the dominant species were monitored during 2004-5.Collections were made from 1-3 hectare fields in 10 locations within 50 Km radius around Shiraz city. Species density was estimated by counting individuals present on 40 winter wheat tillers taken at random along 2 transects 5 m apart in the fields. Eight aphid and 3 parasitoid species were identified through this survey. Rhopalosiphum padi (L.) and Metopolophium dirhodum (Wlk.) with relative abundances of 33.94 and 31.33%, Aphidius rhopalosipi De Stefani-Perez and Praon volucre (Hal.) with relative abundances of 55.53 and 39.90%, were the dominant species of aphids and parasitoids, respectively. Seasonal dynamics of the above species were also studied in Badjgah, located 15 Km north of Shiraz city. Peak populations of the dominant aphids occurred between late May and first of June 2004-5, and those of parasitoids were seen 1-3 weeks later. A comparison between seasonal parasitism of the dominant parasitoids showed significant preferences of A. rhopalosiphi on R. padi, and P. volucre on M. dirhodum. Since the total parasitism of both wasps was nearly 30% of the two aphid hosts, attention should be paid to chemical control programs of wheat pests (such as Sunn pest) so that it does not disturb the efficiency of the aphid parasitoids.
S. Jannat, M. Chizari, S. Abbasi,
Volume 12, Issue 45 (10-2008)
Abstract
The purpose of this study was to investigate dairy farmers' attitudes regarding the quality of milk and role of training in improving the quality of milk. The study was implemented in two parts. The first part was survey research and 6200 dairy farmers were the target population for this study in Golpayegan Township, Iran. Dairy farmers were selected using stratified randomization sampling method (n= 130). In the second part, 12 dairy farmers were selected. Plate count and lipid percentage of milk in 12 dairy farms were determined in a completely randomized block design with 2 treatments and 3 replications. The results of the study showed positive and statistically significant relationship between independent variables (sex, educational level, membership in dairy :::union:::s, knowledge and participation in educational programs) and dependent variable (attitude). Results of analysis of variances showed that plate count and lipid percentage in the two treatments were significantly different.
M Gorji, H Eshghizadeh, A Khosh Goftarmanesh, A Ashrafi, A Moalem, N Poursakhi, N Pourghasemian, A Miladi,
Volume 12, Issue 46 (1-2009)
Abstract
Iron deficiency is a worldwide nutritional constraint in agricultural lands especially in calcareous soils. Cultivation of crops tolerant to Fe-deficiency is an approach to combat Fe deficiency. The aim of this investigation was to evaluate Fe-efficiency of selected important crops in Iran. A completely randomized block design in triplicates was conducted at IUT research greenhouse in fall 2006. Sweet corn (Hybrid K.S.C. 404), grain corn (Hybrid S.C. 500), safflower (cvs. S3110, S-411), sunflower (Hybrid Hyson) and durum wheat (cv. Shuga) were grown in a nutrient solution at two Fe levels (1 and 10 µM Fe-EDTA). The results showed significant (P < 0.01) variation among the studied crops in Fe-efficiency. Corn hybrids were more sensitive to Fe deficiency (FeE = 26%) as compared to other studied crops, and the greatest reduction was observed in their shoot dry matter at 0.1 mM Fe- EDTA treatment. In contrast, the lowest decrease in root and shoot dry matter weight under Fe-deficient condition was found for durum wheat (FeE=94%). Comparing the calculated Fe-efficiency using different indices showed that Fe concentration and content in the whole plant, shoot and root had no relationship with crop tolerance to Fe deficiency.
Z Davarpanah, M Shey Zeinodin, Sh Dokhani, Gh Saeedi,
Volume 13, Issue 47 (4-2009)
Abstract
Sweet tasting glycyrrhizic acid is considered to be the most important chemical compound in licorice root. However, environmental factors affect chemical composition of licorice root including glycyrrhizic acid content. In this study, the effects of the harvesting time and location on licorice root composition were studied. Chemical composition of the licorice roots (Glycyrrhizia glabra) collected in summer and fall seasons from three locations in Fars province (Eghlid, Beiza and Doshman-Ziary) and one location from each of Kerman (Baft) and Kermanshah (Islam-Abad) provinces was determined. Glycyrrizhic acid, ash and sugar content before and after hydrolysis were measured in all samples after extraction. A combined analysis of variances was performed on data based on a randomized complete block design in six replications. The results showed that effects of harvesting season on sugar content, and the effects of location and its interaction with harvesting season on ash, sugar and glycyrrhizic acid content were significant (p<0.01). It was also found that the lowest ash content were obtained from roots harvested from Islam-Abad in summer the highest sugar content before hydrolysis belonged to roots harvested from both Baft and Islam-Abad in fall. Highest amount of sugar after hydrolysis was reported in the roots collected from Islam-Abad in Fall. Roots harvested from Beiza in Fars province in fall had the maximum glycyrrizhic acid content.
A Gholamhoseni Por, M.j Varidi, M Elahi, F Shahedi,
Volume 13, Issue 47 (4-2009)
Abstract
This research was carried out taking into consideration the defects of traditional process in and the most important factors affecting production of rock candy. Selected parameters used for effluent and rock candy consisted of supersaturation at 4 levels (1.3, 1.4, 1.5, and 1.6) and temperature at 3 levels (70, 80, 900C) with 3 replications. The physiochemical tests consisted of pH, color and invert sugar percentage done on all the samples. According to the results, the rise in super-saturation and temperature had significant effect on all the effluent and rock candy characteristics (P<0.01) such that color and invert sugar percentage increased and pH decreased as super-saturation and temperature increased. Furthermore, the interaction effect of super-saturation and temperature on pH, color and invert sugar percentage of rock candy was significant (P<0.01).
E Mahjoubi, H Amanlo, D Zahmatkesh,
Volume 13, Issue 47 (4-2009)
Abstract
In order to examine the effects of increasing concentrations of beet pulp (lipogenic nutrient) substituted for barley grain (glycogenic nutrient) on productive performance, body condition score loss, and blood metabolites, 18 Holstein cows were used in a randomized complete block design. The cows were blocked based on parity. The cows were 171 ± 16 d in pregnancy, 2.76 ± 1.14 parity, and 289 ± 35 d in milk at the beginning of the experiment. The cows' body condition scores were 4.12 ± 0.35 at the beginning of the trial. The cows were assigned randomly to three dietary treatments containing 1) 23.47% barley (0% beet pulp), 2) 14.87% barley (8.6% beet pulp), or 3) 6.27% barley (17.2% beet pulp). Substituting beet pulp for barley grain didn't affect FCM 3.5%, milk protein, lactose, total solid, and SNF percentage, but milk fat percentage (4.37, 4.91, and 5.18, P < 0.003) and milk energy (0.76, 0.82, and 0.84 Mcal/kg, P < 0.02) increased as beet pulp was replaced with barley, respectively. A tendency was detected for a more negative body condition score change (0.13, -0.09, and -0.12, P < 0.13) and back fat thickness (2.5, -0.4, and -1.6 mm, P < 0.13) with added beet pulp. Plasma glucose (65.83, 58, and 57.16 mg/dl, P < 0.01) and cholesterol (157.33, 122.4, and 120.8 mg/dl, P < 0.03) decreased as beet pulp was substituted for barley grain, respectively. No difference was found in the plasma content of insulin and NEFA between treatments. Considering these results, it appears that with inclusion of beet pulp in fat cows diet during late lactation may slightly reduce body condition score safely and inhibit concomitant low production with diet diluting.
A Bohloli, A Naserian, R Valizadeh, F Eftekhari,
Volume 13, Issue 47 (4-2009)
Abstract
Eight multiparous Holstein dairy cows with 634±44 BW, 57±6 DIM, and 46.7±3.1 kg daily milk yield were assigned to a duplicated 4×4 Latin square design for 21-day periods (adaptation, 14d sample collection, 7d). The treatment diets were: 1) no pistachio by-product (control), 2) 5% of pistachio by-product, 3) 10% pistachio by-product and 4) 15% pistachio by-product. Corn silage in control diet was replaced with pistachio by-product. The blood metabolites (2h after feeding), DMI, daily milk yield and milk compositions were not affected by the treatment diets. The economically corrected milk (ECM) and fat corrected milk (FCM) were decreased linearly by increasing pistachio by-product in the diet (P<0.1). By increasing the by-product level in the diet, digestibility of DM, OM, NDF and ADF were decreased linearly (P<0.05). Daily rumination and chewing activity alone or per DMI, NDFI or ADFI were linearly decreased when the by-product level increased in the diet (P<0.1). The results showed that the pistachio by-product does not seem to be suitable for complete replacing of the roughages in the diet and it can be used as a part of forage in the diet up to 10% of DMI.
A Gharehbash, T Ghorchi, S Hasani, N Torbatinejad, H Mansori,
Volume 13, Issue 47 (4-2009)
Abstract
This study was carried out to compare the effects of ewe milk with commercial milk replacer and starter diet with different levels of concentrate on microbial protein synthesis, ruminal fermentation and blood metabolites in the suckling lambs. Thirty Dalagh breed male lambs were separated from their mothers on 3±1 days of age and divided into 6 groups (5 lambs per treatment), and reared in individual cages. Lambs were fed with 6 treatment diets for 90 days age. Treatment diets consisted of 2 fluid feed (ewe milk and milk replacer) and 3 starter diets, 1: 100% concentrate, 2: 67% concentrate and 33% alfalfa hay and 3: 33% concentrate and 67% alfalfa hay. Data were analyzed as a completely randomized design according to 3×2 factorial method. Average of rumen fluid pH, total volatile fatty acids (TVFA), ammonia nitrogen (NH3-N), blood urea nitrogen (BUN), beta hydroxyl butyrate (BHBA), urinary purine derivative excretion (PD), microbial purines (MPD) and microbial nitrogen supply (MN) in lambs fed with ewe milk and milk replacer did not show any significant differences (P>0.05). Average of pH, TVFA (P<0.01), BHBA and MPD, MN were significantly different and higher on lambs fed with starter diet of 100% concentrate than other starter diets (P<0.05). Feeding suckling lambs with all the 3 starter diets affected PD and allantoin to creatinine ratio (P<0.05). This experiment demonstrated that lambs could be reared with milk replacer, without any efeect on microbial protein synthesis, rumen and blood metabolites. Feeding starter diet containing high concentrate to suckling lambs increased microbial protein synthesis and improved rumen and blood metabolites.
S Shrifi, H Rahmani, M Motamedi,
Volume 13, Issue 47 (4-2009)
Abstract
In dairy cattle, the increase in milk yield has been accompanied by a more negative energy balance during early lactation and a decrease in fertility. The 167 amino acid protein product of the ob gene was named leptin (derived from the Greek term ‘leptos’ meaning thin). The leptin hormone, as a 16-kDa protein is synthesized mainly by adipose tissue and is involved in regulation of food intake, energy balance, fertility and immune function. The expression and secretion of leptin are correlated with body fat mass and are acutely affected by changes in food intake. The objective of this study was to investigate the fluctuations of leptin concentrations during late pregnancy and early lactation, the effect of parity and BCS on plasma leptin concentration, and to investigate its fluctuation effects on reproductive status. Blood samples of 54 Holstein cows were taken at a fixed time of the day after milking but before feeding, from 2 weeks before calving until 6 weeks after calving. BCS and plasma leptin concentration were measured at 2-wk intervals. Leptin concentrations were affected by parity. Primiparous cows and cows in first parity had higher leptin concentrations compared with multiparous cows (P<0.05). Leptin concentration was not different in late pregnancy and early lactation. BCS was negatively correlated with plasma leptin concentration (P<0.05). Plasma leptin concentration did not influence reproductive traits (days in milk at first breeding, service per conception and open days).
Z. Hatam, A. Ronaghi,
Volume 15, Issue 58 (3-2012)
Abstract
Application of compost and compost leachate as organic fertilizers can improve plant growth, nutrients uptake and increase phytoavailability of nutrients in soil. A factorial experiment (4×4×2) was conducted in a completely randomized design to evaluate the effect of compost and compost leachate on growth and chemical composition of barley and bioavailability of some nutrients in calcareous clay loam soil and sandy soil under greenhouse conditions. Treatments consisted of four levels of compost (0, 15, 30, and 60 g kg-1), four levels of compost leachate (0, 10, 20, and 40 g kg-1), and two culture mediums (clay loam soil and sandy soil) with three replicates. Results indicated that application of compost and compost leachate significantly increased barley shoot dry matter, the number of tillers, spikes and grain yield in clay loam soil and sandy soil. The maximum barley shoots dry matter and numbers of tillers in both culture mediums were obtained at the highest level of compost or compost leachate, and the maximum number of spikes and grain yield were obtained at the lowest level of compost or compost leachate. Application of compost in clay loam soil and sandy soil increased shoot and root concentrations of nitrogen (N), phosphorus (P), Iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu). However, addition of compost leachate only increased shoot concentrations of Fe and P. Increasing compost levels increased post harvest concentrations of NO3- N, P, Fe, Mn, Zn, Cu and also electrical conductivity and organic matter content of clay loam soil and sandy soil. Addition of compost leachate significantly increased concentrations of Fe, Zn, Cu and also electrical conductivity and organic matter content of both culture mediums. In both culture mediums and both compost and compost leachate treatments, post harvest concentrations of micronutrients were above critical levels. Therefore, addition of these nutrients is not required for the next cultivation. Generally, compost and compost leachate are appropriate organic fertilizers for barley production however, high salinity level in compost leachate, the rate and frequency of leachate application, particularly in sand, needs intensive control and monitoring. Prior to any fertilizer recommendation, the results of this study need to be verified under field conditions, as well.
M. Navabian, M. Aghajani,
Volume 16, Issue 60 (7-2012)
Abstract
In Guilan province, Sefidrud River, as the main source of irrigating rice in Guilan province, has been subjected to increasing salinity and a decreasing discharge because of decreasing in the volume of sefidrud dam, diverting water upstream and entering different sewages into the river. This research tries to determine optimum irrigation depth and intermittent periods in proportion to salinity resistance at different growth stages using optimization- simulation model. After calibration, Agro-hydrological SWAP model was used to simulate different growth stages of rice. Optimization results were obtained for managing fresh and saline intermittent water, 8-day intermittent period, for salinity of 0.747 dS/m in sensitive maturity stage and salinity of 3.36 dS/m in resistant vegetative, tiller and harvest growth stages. It is suggested that the depth of irrigation water be 1, 3, 3 and 5 cm for vegetative, tiller, maturity and harvest stages, respectively. Comparing managements of irrigation and saline based on the resistance of different growth stages to salinity and exploitation of irrigating water with a constant salinity during growth periods of the plant showed that irrigation management based on resistance of different growth periods of the plant to salinity causes rice yield to be improved by 23percent.
M. J. Fereidooni, H. Farajee, H. R. Owliaie, E. Adhami,
Volume 16, Issue 60 (7-2012)
Abstract
Effect of urban sewage and nitrogen on soil chemical characteristics in sweet corn was evaluated in Yasouj region at 2009. Five irrigation treatments were managed common water during entire period of growing season as control (I1) urban sewage during the first half of growing season (I2) urban sewage during the second half of growing season (I3) alternate urban sewage and common water (I4) and urban sewage during entire period of growing season (I5) and three nitrogen rates (N0=0, N80= 80 and N160=160 kg N ha-1) in a completely randomized design with three replications. Results indicated that the soil N, P and K concentrations in treatment I5 had a significant difference compared to the other irrigation treatments. Irrigation levels were also exhibited a significant difference in soil organic matter and EC. Maximum and minimum of soil organic matter were observed in I5 (%0.45) and in I1 (%0.33), respectively. Maximum and minimum of soil EC were found in I5 (2.0 dsm-1) and in I1 (1.4 dsm-1), respectively. Irrigation treatments did not show a significant change in soil pH. The effect of irrigation and interaction between irrigation treatments and nitrogen rates were not significant on available forms of Fe, Zn, Cu and Mn in soil. The effect of nitrogen fertilizer was significant on soil N content. Maximum (%0.034) and minimum (%0.030) of soil nitrogen were noticed in N160 and N0, respectively.
Bita Moravejalahkami, Behrouz Mostafazadeh-Fard, Manouchehr Heidarpour, Saeed Eslamian, Jaber Roohi,
Volume 17, Issue 64 (9-2013)
Abstract
Most furrow irrigation systems have low performance due to deep percolation at the upstream end and tailwater runoff at the downstream end of the field. To eliminate this problem improving furrow irrigation performance is necessary. Since the inflow discharge has high effect on infiltration along the furrow which consequently affects the application efficiency and water distribution uniformity, it would be important to apply different furrow inflow hydrograph shapes based on the field data such as field slope, soil texture and furrow length to save water. To produce different furrow inflow hydrograph shapes, an automatic valve which was connected to a stepper motor was designed to change the inflow discharge with time according to the desired inflow hydrograph shape. The experimental field was located at Isfahan University of Technology. A constant head water delivery system to the furrows including the automatic valve was installed in the experimental field and the tests were conducted for different inflow hydrograph shapes. The comparison of the measured furrow inflow discharges with the simulated furrow inflow discharges produced by the automatic valve showed that the automatic valve can produce different furrow inflow hydrograph shapes with high accuracy.
S. M. J. Mirzaei, , S. H. Tabatabaei, M. Heidarpour, P. Najafi,
Volume 17, Issue 66 (2-2014)
Abstract
There chemical and organic matter content in garbage leachate that may affect soil physical and hydraulic properties. The main objective of this study was to evaluate the influences of the leachate of Isfahan Organic Fertilizer Factory (IOFF) on some soil physical and hydraulic properties in a soil chemically enriched by Zeolite. The treatments include two soil textures (clay loam and sandy loam) and three levels of zeolite (0, 5 and 10 percent). The treatments were applied on lysimeters scale. The results showed that irrigation with the leachate caused a reduction of infiltration and hydraulic conductivity in the clay loam soil. The hydraulic conductivities in clay loam soil without zeolite (B0) before and after irrigation with leachate were 1.73 and 0.36 m/day, respectively. In contrast, there were no changes in the sandy loam soil’s infiltration and hydraulic conductivity. The hydraulic conductivities in the sandy loam soil with 5 percent zeolite (A5) before and after irrigation with leachate were 3.17 m/day. Furthermore, zeolite had a decreasing effect on those processes. The results show that irrigation with leachate caused reduction of bulk density in two types of soil and all levels of zeolite.
D. Khosraviani, A. R. Davoudian Dehkordi, J. Givi, M. Sheibi,
Volume 19, Issue 74 (1-2016)
Abstract
The concentrations of rare-earth elements (REEs) were determined with the aim of investigating the behavior of these elements in granitic rock, granitic soils and soils between rock and lichen in Shir-kuh of Yazd province. Rare earth element patterns of the P-rich granite were determined by the mixture of Eu-enriched feldspars, middle REEs to heavy REEs-enriched apatite and Light REEs-enriched monazite. Granite-normalized REEs patterns for soils and soil lichen-granite interface represented the same signatures and similar to parent rocks. The REEs levels of the soils lichen-granite interface were similar to the concentrations of the elements in the natural compositions (Upper Continental Crust and Post-Archean Australian Shale). PAAS-normalized Rare earth element patterns for three soils’ lichen-granite interface were identical to each other and PAAS and close to the reference axis (PAAS). The same signatures of REEs in granitic rock, granitic soils and soils lichen-granite interface in arid and semi-arid mountainous areas indicate that the elements are immobile and therefore, they can be used as a suitable tracer in soil provenance studies.
F. Jahanbakhshi, M. R. Ekhtesasi, A. Talebi, M. Piri,
Volume 22, Issue 2 (9-2018)
Abstract
One of the main sources of runoff in arid and semi-arid mountainous highlands is typically composed of before Quaternary formations. Since the structure and lithology of formations are different, varying formations can have different significance in terms of runoff and sediment. The present study aimed to investigate the sediment production potential and the runoff generation threshold on three formations (Shirkooh Granite, Shale, Sandstone and Conglomerate of Sangestan and Taft Limestone) in Shirkooh mountain slopes. The 60 mm/h rainfall intensity with the 40 minute continuity, according to region rainfall records, and the ability of the rainfall simulator were selected as the basis for the study. Field experiments were conducted in dry conditions based on one square meter plot on rocky slopes with a gradient of 20 to 22 percent and a maximum thickness of 30 cm of soil. The results showed that in 60 mm/h rainfall intensity, the minimum rainfall to produce runoff on Sangestan, Shirkooh and, Taft, was 10, 10.7 and 16.7 mm, respectively. The maximum amount of the sediment was measured on Sangestan, Taft and Shirkooh, respectively. Statistical tests related to runoff and sediment production on all three formations confirmed a significant difference at the 5 % level. In terms of the time required to start runoff, the minimum time was for Sangestan, Shirkooh and Taft, respectively. According to the results, in terms of the potential for runoff generation and sediment production, Sangestan, Shirkooh and Taft can be ranked from high to low levels.
Z. Abbasi, H. Azimzadeh, A. Talebi, A. Sotoudeh,
Volume 22, Issue 4 (12-2018)
Abstract
Groundwater quality evaluation is very necessary to provide drinking water. Groundwater excessive consumption can cause subsidence and penetration of saline groundwater into freshwater aquifers in Ajabshir Plain, on the Urmia lake margin. The main goal of the current project was to evaluate the groundwater quality by employing the qualitative indices of groundwater and GIS. Ten parameters of 15 wells including EC, TDS, total hardness as well as the concentration of Ca++, Na+, Mg++, K+, SO4--, HCO3- and Cl- were analyzed. At first, the maps of parameters concentration were prepared by the kiriging method. Then based on WHO drinking water standards, the maps were standardized and ranked for drawing the maps of quality indices. The results showed that quality index changes were in the range of moderate (61) to acceptable (81). Removing the single map method of sensitivity analysis detected the quality index was more sensitive to the K+ parameter. Finally, the quality index from the eastern north to the western south of Ajabshir Plain and the other areas was ranked in the acceptable and moderate classes, respectively.
M. Iranpour Mobarakeh, M. Koch,
Volume 23, Issue 4 (12-2019)
Abstract
Nowadays, with the increasing population in Iran, especially in arid and semi-arid areas, as a result of the growing importance of the quality of water resources, including groundwater, field experiments and many simulations have been conducted for the development of groundwater contamination through powerful and up- to- date software. However, in most cases, there is a tangible difference between the measured data in laboratories and the data produced with software; this is why the scientific validation and verification of the research results could be declined. In this study, in order to justify and correct these data, the calibration principle was used to minimize the error of testing and modeling. The purpose of this study was to validate and verify the SUTRA model for different scenarios of the solute transport in a sand tank with heterogeneous hydraulic conductivity to evaluate transverse dispersivity. In this study, coding was initially performed for the configuration and calibration of the SUTRA numerical model to simulate different scenarios of the solute transport in a heterogeneous sand Tank in the Hydraulic Laboratory of the University of Kassel, Germany, until acceptable values were obtained. Then the results were compared with the experimental model. In order to validate and verify the data obtained from the simulation with the SUTRA model, the relevant concentration profiles were compared with the results of the experimental model. The results of the numerical and laboratory models revealed the density effects by sinking the geometric center of the mixing zone for the low concentrations of salt, C0 = 250 ppm. The results also showed that the width of the mixing zone between salt and fresh water depended on the amount of longitudinal dispersivity, especially the transverse dispersivity. By analyzing the results of simulation and experiment, it was observed that with increasing the velocity, reducing the amount of sinking and raising the input concentration, the time needed to achieve the steady dispersion was decreased.
B. Torabi Farsani, M. Afyuni,
Volume 25, Issue 1 (5-2021)
Abstract
Compost leachate is a liquid resulting from physical, chemical and biological decomposition of organic materials. The main objective of this study was to evaluate the influence of leachate compost on the physical, hydraulic and soil moisture characteristic curves. Also, the effect of leachate on the aerial organ fresh weight of corn was investigated. Leachate was added to clay loam and sandy clay loam soils at the rate of zero, 1.25 and 2.5 weight percent. The soil water characteristic curve and the estimation of the parameters of the van Gnuchten and Brooks and Corey models were performed using RETC software. Leachate increased the bulk density and decreased the available water of the clay loam soil. Only 1.25% of the leachate increased the available water in the sandy clay loam soil. Two levels of leachate decreased the bulk density of sandy clay loam soil. Leachate decreased the saturation hydraulic conductivity of the clay loam and increased this parameter of sandy clay loam soil. Leachate was more successful in increasing the aerial organ fresh weight of corn in the sandy clay loam soil. Therefore, leachate was more useful in sandy clay loam than in clay loam soil, and 1.25% treatment was better in the sandy clay loam soil. Also, the used leachate increased the repellency of both soils. Leachate caused the parameters of van Gnuchten and Brooks and Corey models to increase, as compared to the control in both soils.
