Showing 32 results for Ebrahimi
R. Fotouhi Ghazvini, Y. Hammidoghli, Y. Ebrahimi,
Volume 5, Issue 2 (summer 2001)
Abstract
In order to produce Tristeza virus-free plants from Satsuma mandarin (Citrus unshiu) cultivars (Ishikawa, Sugiyama and Myogawa), unfertilized ovules of plants suspected of CTV (Citrus Tristeza virus), from Mazandaran Mahdasht orchard were cultured on 4 media.
Embryogenesis of nucellus tissue of ovules from Ishikawa and Sugiyama cultivars on MS medium were 31% and 25% and on MT medium from Ishikawa was 40.5%. Unfertilized ovules of Myogawa did not germinate on all media.
Nucellar embryos of Ishikawa and Sugiyama developed on MT+GA3+ME were 83% and 95%, respectively. Embryo differentiation, leaf and plantlet formation were observed on MT+GA3+ADE+ME medium. In the stage of two leaves, the plantlets’ growth under 1500 lux illumination was twice its growth under 800 lux illumination. Budding of in vitro plantlets from both cultivars on susceptible to Tristeza and virus-free seedlings of Key Lime did not show any infection by Tristeza.
S. Seyedebrahimi, R. Ebadi, M. Mobli, B. Hatami,
Volume 8, Issue 1 (spring 2004)
Abstract
In order to study the nectar quantity and quality of some onion cultivars and honeybees foraging activity on them, a complete randomized block design with three replications was conducted. Ten selected onion cultivars consisting of Ghom, Kashan, Azarshahr, Dorcheh, Tarom, Kazeroon 1, Kavar, Abarkooh, Hurand, and Yellow Sweet Spanish were used. Sixty mm mother bulbs of different onion cultivars were planted in 3×4 m plots on 6 lines. The distance between rows was 35 cm and plants were spaced 25 cm apart on each row. At flowering time, bees’ activity on the inflorescences was studied and flower nectar was collected in 10 micro-liter capillary tubes. Nectar volume was determined and analyzed. Mean numbers of honeybees visiting on inflorescence every 10 minutes and the mean residing time of each honeybee on a seed stalk (inflorescence) were significantly different in different cultivars. Hurand flowers had the least number of visitors and Dorche flowers had the longest visiting time. The amount of nectar varied in different cultivars, so did glucose (G), fructose (F), and sucrose (S) contents. Except for the Abarkuh cultivar that had more glucose than it had other sugars, all the cultivars had higher quantities of fructose than they had other sugars while sucrose had the least quantities among the sugars. Nectar sugar ratio in most of the cultivars was hexose dominant, which was identified by the low S/(F+G) ratio. Potassium, calcium, and sodium contents in nectar were different in different cultivars, too. Finally, the results showed that foraging activity of honeybees on onion inflorescences depends on the interactions of several factors such as nectar quantity and, more importantly, on sugar quantity and ratio as well as potassium content. .
E. Ebrahimi, J. Pourreza, S. V. Panamariov, A Kamali, A. Hosaini,
Volume 8, Issue 2 (summer 2004)
Abstract
A 3×4 factorial experiment was conducted for 45 days to determine the effects of diets containing different levels of protein and fat on growth of fingerlings Beluga (Huso huso L.1758). Twelve different diets were formulated with 3 levels of protein (45,50 and 55) and 4 levels of oil including fish oil and sunflower oil (0.5 ,4 , 8 and 12). 1260 Beluga fingerlings with an initial body weight (IBW) of 2.2 gram, after adaptation to the experimental conditions, were selected and stocked randomly into 36 fiberglass tanks (100 water volume) at 35 fish per tank, and fed on experimental diets for 45 days. Two ways analysis of variance showed that the percentage of body weight increase (%BWI), specific growth rate (SGR),protein efficiency ratio (PER), food concumpsion ratio, and productive protein value (PPV) content were significantly (P<0.05) affected by different protein and fat levels. Fishes fed on diets No.3 (containing 45% protein and 14 % lipid) and No.8 (containing 50% protein and 17 % lipid) showed the highest increase in body weight percentage, the best specific growth rate, protein efficiency ratio, and lowest food concumption ratio. Besides, the highest productive protein value was observed in diet No.2 (45% protein and 10.5% lipid) and diet No.3 (45% protein and 14 % lipid).Comparison of chemical composition of examined fish corps indicated a significant difference in their protein and lipid contents (P<0.05). However, the composition of the diet, revealed no significant changes on the dry matter and ash content of the body. Based on the findings of the present study 45-50% dietary crude protein is recommended for the optimum growth of Beluga fingerling. Moreover, the rate of needed lipid for optimum growth of fingerling range is from 14 to17 percents.
E. Karami, K. Rezaei- Moghaddam, H. Ebrahimi,
Volume 10, Issue 1 (spring 2006)
Abstract
Increasing the water use efficiency through promotion of sprinkler irrigation system, in order to increase production, has been the aim of the Ministry of Agricultural-Jihad in the past decade. Considerable amount of investment and efforts have been devoted to this end. Therefore, investigation of these efforts and development of models to predict the adoption behavior of farmers are of considerable importance. A survey research was conducted in four provinces (Fars, Bushehr, Kohkiloye-va-Boyerahmad, and Chaharmahal-va-Bakhteyari). A stratified random sample of 422 farmers was interviewed including 124 and 298 adopters and non-adopters, respectively. The findings indicated that the discriminant model developed based on the multiplicity model is a better predictor of farmers’ adoption behavior than diffusion and farm structure model. Application of multiplicity model in extension of sprinkler irrigation can increase the adoption rate and as result the efficiency of extension efforts.
M. A. Ebrahimizade, A. M. Hassanli ,
Volume 12, Issue 44 (summer 2008)
Abstract
Root depth is one of the main parameters affecting soil moisture availability held within the plant root zone. This study was conducted to evaluate the trend of corn root development during the growing season in different irrigation methods with two water qualities, and distribution of roots in soil profile. The experiment was a split plot design with three main treatments (subsurface drip(SSD), surface drip(SD) and furrow irrigation(FI)) and two sub main treatments (municipal effluent and fresh water) in two consecutive years conducted in Korbal plain, Fars province. Root monitoring was carried out with the observation of soil profile root depth measurement. Samples were taken during the growing season 16 times, each with a 7 day interval. Measurement of root weight in different soil layers was carried out using monoliths of soil washed with water pressure using 50 mesh sieves. Although the longest roots were observed in plots irrigated with SSD and the shortest in FI, the final root length was not significantly affected by irrigation methods and water qualities. In this research, a model showing the trend of root length average growth was developed and tested in the experiment conditions. The average final main root depth for all treatments was 77 cm. Irrigation volume using root depth monitoring could be reduced compared to linear model, Borg & Grimes and CROPWAT model for root depth estimation. Irrigation water on the base of soil moisture deficit within the root zone in each irrigation event could be reduced when the real root depth is considered compared with the conventional general models giving a final root depth. Results showed the total dry root weight in SSD was more than that in SD and FI methods. However, water quality did not show a significant effect on dry root weight. The most root concentration in SSD was measured in depth of 20-40 cm, while in SD and FI the most concentration was in surface layer (0-20 cm). In the SSD, the roots were distributed more evenly compared with SD and FI methods. The concentration of roots in all treatments below 65 cm was not significant.
M. Ramazani, H.a. Samizadeh Lahiji, H. Ebrahimi Koulabi, A. Kafi Ghasemi,
Volume 12, Issue 45 (fall 2008)
Abstract
In order to study agronomic and morphological traits in maize hybrids in Hammedan, two early (108 and 301), three medium (604, 647 and TWC647) and two late maturing (704 and 711) hybrids were evaluated in a randomized complete block design with three replications in Agricultural and Natural Resources Research Station in Hammedan in 2005. 33 morphological and phonological traits were recorded from 10 plants randomly selected from two central rows of each plot. The maximum and minimum grain yield was obtained from SC647 and SC301, respectively. The grain yield had the highest correlation with dehusked ear weight. Factor analysis of data after varimax rotation identified four factors that accounted for 98.03% of total variance. The scatter plot of hybrids based on the two first factors (the seed yield factor and phenological structure factor) showed that SC704 had the maximum forage yield and the best physiological characteristics and SC647 had the maximum grain yield, cob diameter and number of seed in row.
M Ebrahimi, S.m Khayam Nekoei, S Kadkhodaei,
Volume 12, Issue 46 (fall 2009)
Abstract
Somatic embryogenesis is affected by several factors. In this research project, we studied the effect of explant size, wounding and desiccation treatments on somatic embryogenesis and their conversion into plantlet among three genotypes of soybean. The explants were sampled from immature embryos of soybean in three different sizes (3, 5 & 7 mm) with wounding treatment on half of each, and then were cultured on the somatic embryogenesis medium. In order to determine desiccation effect on conversion amount of embryos into plantlets, the produced embryos were affected by three levels of desiccation treatments (2, 4 & 6 days). The increase ratio of callus mean weight, percentage of embryogenic calli, embryo number per explant and percentage of embryo conversion to plantlet were used for treatment evaluation. Variance analysis of the data showed significant differences (P<0.01) between treatments regarding the variables. The results indicated that BP was a superior genotype with embryogenic capability (24.19 %) and the best explant size for somatic embryogenesis was immature embryo with 3 mm length. The six day desiccation treatment caused highest percentage of embryo conversion into plantlet (74.7 %). Wounding increased callus production on explants and number of embryos per explant (20.28), but it did not show any significant effect on percentage of embryogenic calli. Germinated somatic embryos were transferred to pots containing peat-moss. Somatic embryogenesis is an efficient method for the plant regeneration and genetic transformation. However, this method still offers low percentages of plant regeneration, and is perhaps related to the maturation process and high morphological abnormalities of the matured embryos. This study aimed to find some solutions for soybean somatic embryogenesis problems.
M. Akbari, B. Nazari, M. Parsinezhad , H. Ebrahimian,
Volume 16, Issue 62 (Winte - 2013 2013)
Abstract
This study was conducted on subsurface drainage network under operation in Behshahr. DRAINMOD model was used to simulate drainage system using measured data in 2006. The model was evaluated to estimate soil hydraulic conductivity by comparing the measured and predicted values of water table depth and drain discharge for different values of hydraulic conductivity. The results of this method were compared with the results of output drainage water method (as a baseline method). Use of water table depth simulation results in estimating hydraulic conductivity model resulted in considerable error, while the simulation results of drain discharge rate could be used with good accuracy for estimating it. There was a small difference between the output drainage water method and the inverse solution of DRAINMOD model to estimate soil hydraulic conductivity (2.3 and 2.5 cm/h, respectively). Thus, the comparison between the measured and predicted values of drain discharge could be a good criterion to estimate soil hydraulic conductivity using the inverse solution of the DRAINMOD model
N. Kaveh, A. Ebrahimi,
Volume 17, Issue 63 (Spring 2013)
Abstract
Riparian vegetation is a component of river system that performs certain basic functions including primary vegetative production, protecting stream banks from erosion, trapping sediments, promoting water quality, wildlife habitat and fisheris, forage for livestock, etc. In this research, spatio-temporal change of vegetation riparian area of Aghbolagh-river as an upstream of Karoon-river for 65-km was investigated using 1956, 1969, 1998 aerial photos and 2006 satellite images. Results showed a significant change in riparian area between different periods (kappa=26.55%). This change is the result of construction of dam in the upstream in 1993, alteration of riparian area to arabal land, exploitation of groundwater for agricultural usage, etc
M. Ebrahimi, M. Jafari, E. Rouhimoghaddam,
Volume 19, Issue 72 (summer 2015)
Abstract
The present study was conducted to increase phytoextraction efficiency of Festuca ovina L. in lead contaminated soil in the EDTA-assisted (0, 1.5, 3, 1.5+1.5, 3+3, 6 mmol kg−1), assess the best time of plant harvesting to increase Pb uptake and method of EDTA application to reduce Pb leaching risk. The results revealed that the greatest Pb uptake was observed in 3EDTA treatment. Therefore, 3mmolkg-1 was used in the second step for assessing harvest time for 15, 30 and 45 days. Results showed that the concentration of Pb in plant tissues was increased with the passage of time and the best harvest time to achieve maximum removal of Pb was 60 days of the first harvest. In the third step to reduce leaching of Pb-chelate, 3mmolkg-1 EDTA in five ways of single, double, triple, quadruplet, quintuplet were added to the soil. The results indicated that under quintuplet application, Pb content reached its minimum concentration in the soil and in the plant organs, the Pb concentration was maximum and metal concentration in the plant organs did not vary significantly when triple, quadruplet and quintuplet dosages were added (p<5%). Overall, optimum phytoextraction of F. ovina L. and Pb leaching reduction were achieved when 3mmol kg−1 EDTA was added in quintuplet dosage and the plant was harvested at the end of growth stage.
N. Basirani, H. Karimi, A. Moghadamnia, H. Ebrahimi,
Volume 19, Issue 72 (summer 2015)
Abstract
Erosion and sedimentation as a river natural behavior lead to the loss of soil and cause irreparable damages to water development projects. Since the phenomenon of erosion and deposition is one of the most complex natural processes, the complete understanding of the effective factors involved in this phenomenon is really a big problem. This study was done to optimize the parameters affecting sediment yield and determine their sensitivity in the Doiraj river basin in the West of Iran, using SWAT, a semi-distributed model, and SUFI2 algorithm, and the monthly sediment yield from 1994 to 2004. In the first run of the model, coefficients R2, NS, and Br2 were respectively obtained as 0.43, 0.39 and 0.28. The results showed that performance of the model with the default data was not satisfactory and we needed to determine the used optimal values. Then, the optimal values of parameters were determined using SUFI2 algorithm and reverse modeling and the model was run with the new values. Based on the new results, coefficients R2, NS, and Br2 were respectively obtained as 0.75, 0.73 and 0.65 and performance of the model improved and its accuracy increased acceptably. In the next step, from among the studied 30 parameters, (CH_N2), (USLE_K), (USLE_P) and (OV_N) were identified as the important parameters effective in the output of the sediment yield from basin. Also, USLE_K as was diagnosed as the most sensitive parameter. Results of this survey can be used in the management of the effective parameters in sediment load. Determining exact values of the effective parameters in other studies can be helpful to improve the simulation results in similar basins, too.
D. Dezfooli, S. M. Hosseini-Moghari, K. Ebrahimi,
Volume 20, Issue 76 (Summer 2016)
Abstract
Precipitation is an important element of the hydrologic cycle and lack of this data is one of the most serious problems facing research on hydrological and climatic analysis. On the other hand, using satellite images has been proposed by many researchers as one of practical strategies to estimate precipitation. The present paper aims to evaluate the accuracy of satellite precipitation data, provided by PERSIANN and TRMM-3B42 V7 in Gorganrood basin, Iran. To achieve this aim, two sets of daily precipitation ground-based data, 2003 to 2004 and 2006 to 2007, from six stations of Gorganrood basin, named; “Tamer”, “Ramian”, “Bahalkeh-ye Dashli”, “Gorgan Dam”, “Ghaffar Haji” and “Fazel Abad” have been used in this paper. The evaluation indices have been calculated and analyzed in different time scales, including daily, monthly and seasonal. The results indicated that the two above mentioned satellite models are not accurate in daily scale. However, they showed reasonable accuracy in monthly and seasonal scales. The highest correlations between satellites and recorded data in daily and monthly scales, for TRMM-3B42 V7 in “Gorgan Dam” and “Bahlke Dashlei” stations, are 0.397 and 0.404, respectively. The comparison of measured and satellite data of winter showed better agreement for PERSIANN model. However, TRMM-3B42 V7 shows better correlation in other seasons. The results also indicated that while TRMM-3B42 data displays higher correlation with measured data, PERSIANN provids better results in predicting the number of rainy days.
V. Rezaverdinejad, H. Ahmadi, M. Hemmati, H. Ebrahimian,
Volume 20, Issue 76 (Summer 2016)
Abstract
In this study, two different approaches of infiltration parameters estimation in traditional, variable and fixed alternate furrow irrigation, with and without cutback inflow, were performed and compared. Four usual methods including two-point (Elliott and Walker), Valiantzas one-point, Mailapalli one-point and Rodriguez and Martos optimization methods, as approaches based on advance data, and multilevel optimization method as an approach based on the advance, storage and recession data, were considered. Surface irrigation model: WinSRFR was used to simulate irrigation phases and infiltration value in each method. 13 furrow irrigation field experiments, from two case studies: Karaj and Urmia, were used to perform different methods. Based on the results, the multilevel optimization method predicted the advance and recession phases and runoff-infiltration with high accuracy for traditional, variable and fixed alternate furrow irrigation. The multilevel optimization method for traditional furrow irrigation, showed more accuracy than variable and fixed alternate furrow irrigation in advance and recession phases and the average root mean square error (RMSE) for predicting advance phase for the three furrow irrigation methods was 1.37, 1.8, and 1.57 minutes and for the recession phase was 3.76, 5.0, and 3.03 minutes, respectively. Also the multilevel optimization method for cutback options indicated high performance to advance and recession prediction and the average RMSE of advance and recession prediction were obtained 3.57 and 2.13 minutes for cutback option and 3.8 and 1.3 minutes for no cutback option, respectively. The multilevel optimization method indicated high performance in storage phase, too. The average of relative error (RE) of runoff estimation for traditional, variable and fixed alternate furrow irrigation was calculated 0.5, 0.4 and 0.4 percent, respectively. The runoff average RE of multilevel optimization method with cutback and no cutback option were obtained 1.85 and 0.85 percent, respectively; that showed high performance of this method for no cutback option in comparison with the cutback option. Therefore, the use of data of all irrigation phases to estimate infiltration parameters shows better performance in the prediction of irrigation and water balance components. (run-off and infiltration).
M. Khalaji, E. Ebrahimi Dorche, H. Hasheminejad,
Volume 21, Issue 1 (Spring 2017)
Abstract
Water quality assessment is important in late years coincide white decreas quantity it. The Zayande-Rood's Dam Lake is one of the important water resources that supplies drinking water for human populations in Isfahan, This lake also supplies water resources for agricultural sections of these provinces. Five points were determined as the sampling stations. Samplings were performed from May, 2013 to March, 2014 in seven steps, once every forty five days in for seasons (two times in each season). The water quality parameters (DO, NO3, NO2, EC, pH, hardness, TDS, NH4, BOD5) were measured in all the stations and stages, and then water quality indexes were calculated. According to the results of this study, the water quality of the Zayande-Rood's Dam Lake estimated as good (50-100), with using WQI index. WQI index maximum was in summer (84.63) and minimum was in autumn (66.4). Considering the importance of the Zayande-rood's dam lake as a supplying resource of drinkable water of Isfahan. It seems that further attention in the lake watershed management is needed in order to protect water quality.
S. Ebrahimiyan, M. Nohtani, H. Sadeghimazidi,
Volume 21, Issue 2 (Summer 2017)
Abstract
The basis of spatial planning is the geomorphological zoning of ground surface, in which the first phase is determining the homogeneous zones of the ground surface in terms of geomorphological characteristics. The current study aimed at determining the proper zones for artificial feeding in Gahar mountainous region and Garebayegan plains in Fars province by the use of zoning the ground by Evans-Chezy quantitative coefficients. The quantitative zoning of ground surface plays a vital role in more accurate determination of the land capabilities due to precise determination and division of the types, facies, and surface terrains. For this study, the elevation numeral data with 10m resolution obtained from the National Cartographic Center was used. By the use of surface fitting tools in MATLAB software, the equation for each form was fitted to limited fragments of the surface and the program was applied. Then, each of the quantitative coefficients was illustrated as some zones. For determination of fitting degree, the total squared difference between the rate parameter was used and by the use of fitness degree, the propriety degree of the surface for optimal positioning of flood spreading with surface morphological view was determined. The results indicate that the surface downstream the alluvial fans and plains located on the southern region of the studied land is the most appropriate zone for the Flood Spreading. This area constitutes a surface of 10% of the total area of the region.
M. Mirmohammad Sadeghi, B. Ebrahimi, M. Pasandi,
Volume 22, Issue 2 (Summer 2018)
Abstract
Depletion and consequently reduction in groundwater storage results in numerous harmful environmental effects such as reduction in yields of wells, land subsidence, lowering of water quality and also reduction in storage of surface water bodies having hydraulic relation with aquifers. In this research, groundwater depletion in the Najafabad subcatchment aquifer located in the GavKhouni basin, Isfahan province was evaluated. These studies indicate groundwater depletion and deterioration of the aquifer water quality during the recent years. Zayandehroud River had been effluent and it has recently converted to influent and dominantly recharges the aquifer. The groundwater depletion in this region has been due to wells overpumping and it does not comply with the uniform rainfall variations in recent years. According to the shaly aquifer bedrock, the groundwater depletion cannot be due to leakage through the bedrock. Moreover, the groundwater quality has been deteriorated in all parts of the aquifer, especially in the regional drawdown cones resulted from recently groundwater overexploitation by deep wells. The river leakage to the aquifer is predicted to be persistent and increasing according to results of the research and it is necessary to limit the groundwater extraction and change the average surface water inflow to the area to mid 1370s condition.
P. Hadipour Nicktarash, H. Ghodousi, K. Ebrahimi,
Volume 22, Issue 4 (Winter 2019)
Abstract
One of the factors leading to the contamination of water resources is human activity, producing waste materials. In this paper, the effects of contamination on the water quality of Taleghan River, was simulated using of Qual2k model and the seasonal changes were evaluated. The qualified data collected during two months, August (as the dry season) and February (as the wet season), were used in the modelling. The results showed that the dissolved oxygen change was in the range of 4.5-6.52 mg/L in August. However, it changed between 4.8-5.3 mg/l in February and this reduction in the wet season was due to the run off deposition and the seepages of farmland near the river. Furthermore, BOD in the wet season and the dry season changed by 6-31 and 10-26 mg/l, respectively. These changes were due to the sewage dilution in flow during the wet season. Evaluation of the pH values in wet and dry seasons also showed that water of the river was more alkaline in the wet season, which is due to the effect of non-point resources or the fertilizer entrance after farm land bleaching by rain. Evaluation of Taleghan river EC variation also showed these changes were not significant during the wet and dry seasons. Water temperature was altered by 3-100C and 19-250C, respectively, in February and August.
N. A. Ebrahimipak, A. Egdernezhad,
Volume 23, Issue 1 (Spring 2019)
Abstract
Sugar beet is one of the most important agricultural crops and its yield depends on irrigation water. Due to the impossibility of assessing the effect of all water amount strategies on sugar beet yield, it is necessary to use crop models such as WOFOST, AquaCrop and Cropsyst. In order to achieve this goal, a set of data collected from Shahrekord’s Agricultural Research Station were used. Treatments consisted of irrigation water amount (in five levels: E0: 100%, E1: 85%, E2: 70%, E3: 55%, and E4: 30%) based on crop evapotranspiration in different growth stages (T1: initial, T2: T2: mid-season, and T3: late season). The values of RMSE statistical criteria for the results of AquaCrop, WOFOST and CropSyst simulation were equal to 0.57, 0.68, and 0.26 ton.ha-1, respectively. NRMSE results were also obtained to be 0.11, 0.13, and 0.05 ton.ha-1 for the mentioned crop mpdels, respectively. The results of the EF criteria revealed that CropSyst (0.91) had better efficiency, as compared to AquaCrop (0.62) and WOFOST (0.47). Regarding the results, it is suggested to use CropSyst to simulate sugar beet yield in similar conditions.
E. Ebrahimi, M. Zare Shahraki, O. Farhadian, Y. Keivany,
Volume 23, Issue 4 (winter 2020)
Abstract
Benthos play an important role in the transmission of primary production and organic material (detritus) accumulation of the substrate in the water ecosystems to the higher levels of food chain. Also, they are used as biological indicators to evaluate the effect of pollutants caused by human activities on water ecosystems. To evaluate the benthic communities of Zayanderood Dam Lake, 4 sampling stations were selected on the lake; then, during the year 2014, seasonal sampling at each station was performed. The sampling was carried out by using the sediment sampler instrument with the dimensions of (20 cm × 20 cm). The average temperature of surface and deep water in the Zayanderood Dam Lake during the study was estimated to be 15.6 ± 2.4 and 8.9 ± 1.8°C, respectively. The average concentration of dissolved oxygen in the surface and deep water was varied from 10.3 ± 0.6 to 8.1 ± 0.7 mg/L, respectively. Totally, 2165 samples of benthos were collected and identified in the Zayanderood Dam Lake, belonging to 3 classes, 6 orders and 5 families. The maximum number of samples belonged to Tubifex, Naididae and Chironomidae genera. The dominant genus was Tubifex in all stages. According to this study, therefore, it seems that the structure of substrate, the amount of nutrients, grazing pressure and hydrostatic pressure are the most important environmental factors that can affect benthic community in the Zayanderood Dam Lake.
A. Ebrahimi, M. Shayannejad, M. Reza Mosaddeghi,
Volume 23, Issue 4 (winter 2020)
Abstract
Wetting pattern in a trickle irrigation system is one of the most important characteristics that should be taken into consideration for designing the irrigation systems. Improving the dimensions of the wetting pattern will increase the water use efficiency and irrigation systems. The objective of this study was to investigate the effect of rice husk and its biochar application on the wetting pattern in a silty clay soil under surface trickle irrigation. A box with the length of 200, the width of 50 and the height of 100 cm was used. To easily fill and empty the model, it was filled up to a height of 50 cm. The rice husk and its biochar were added to the soil at the rates of 0, 1 and 2 mass percentages based on a factorial arrangement of the treatments in a completely randomized design with three replications. Biochar was prepared in a special furnace at 500°C without oxygen. The experiments were done with a flow rate of 4 liters per hour with the irrigation time of 3 hours. The results of the analysis of variance showed that the organic treatments increased the soil water content in the range of field capacity to a permanent wilting point; the highest increase was observed for the biochar 2% treated soil. Also, the addition of rice husk and biochar in the silty clay soil reduced the horizontal advance and increased the vertical advance wetting pattern.
