فهرست مطالب f. abbasi

Age, growth, and reproductive traits of the South Caspian Spirlin in the southern part of the Caspian Sea basin, Tajan, River, were investigated. A comprehensive study was conducted on 663 specimens including 226 females, 297 males, and 140 unsexed individuals with a total length ranging from 25.88 to 121.66 mm. The specimens were collected using an electrofisher at monthly intervals. The female-to-male sex ratio was calculated as 1: 1.29. The growth rings on the scale were employed for age determination in this study. Both sexes exhibited only four age groups (0+ to 3+), with the 2+ age group dominating the population. Females consistently displayed larger sizes compared to males. The von Bertalanffy growth function yielded L t =123.90 (1- e -0.25(t+0.87) )  and L t =128.10 1- e -0.29 t+0.69  for males and females, respectively. Furthermore, the Fulton condition factor value was significantly higher in females than males. Notably, the maximum gonadosomatic index for both males and females coincided with the spawning seasons (May to August). Absolute fecundity varied from 290 to 1710 oocytes, with a mean of 793 oocytes. This study presents comprehensive data on the biological characteristics of the South Caspian Spirlin, providing valuable insights for fish stock assessment studies.

Experts believe that motivation plays an important role in the academic performance of students and according to the current conditions, various factors can improve it. Among these factors, psychological and social well-being is considered as effective variables. Therefore, this study was conducted with the purpose of determining the role of psychological and social well-being on the academic motivation of nursing students through the mediation of academic civic behaviors.

This is a correlational descriptive study. The statistical population consisted of nursing students of Tabriz University of Medical Sciences during the academic year of 1400-1401 (2021-2022). The number of 250 people was selected out of available 700 nursing students based on Morgan's table using stratified random sampling method. Harter's academic motivation questionnaire (1981), Rief's psychological well-being (1989), Keyes' social well-being scale (2004) and Gol Parvar's academic civic behavior questionnaire (2019) were used to collect data. Data analysis was performed using Pearson's correlation coefficient and structural equation analysis using SPSS-21 and Amos-22.

The results of showed that there is a positive and significant relationship between social well-being and its components (including prosperity, correlation, cohesion, acceptance and social participation) and psychological well-being and its components (including self-acceptance, positive relationships with others, autonomy, control over the environment, purposeful life, and personal growth) and academic motivation (p<0.05). Furthermore, academic civic behaviors have a mediating role in the relationship between psychological well-being and its components and social well-being and its components and academic motivation (p<0.01).

Based on the study findings, due to the influencing role of psychological and social well-being on variables such as academic motivation and civic academic behaviors in nursing students, universities should make efforts to hold consultation centers inorder to increase psychological well-being and academic motivation of their students

Missed nursing care seems to be controlled by factors such as social support. The present study was conducted with the aim of determining the relationship between perceived social supports and missed nursing care in working nurses.

In this descriptive correlational study, 156 nurses working in teaching hospitals of Hamedan city were selected by randomized stratified sampling method. The data collection tools included: Checklist of demographic characteristics, Perceived Social Support Scale by Zimmet et al., and Missed Nursing Care Questionnaire by Kalish and Williams. Data analysis was done in SPSS 24 software with descriptive statistics and Pearson, Mann-Whitney and Kruskal-wallis correlation coefficients. Also, the significance level of the tests was less than 0.05.

The results of study showed that 53.8% of the nurses were female and 82.7% have bachelor's degree, and the scores of perceived social support and missed nursing care were 45.35±5.74 and 6.92±46.32, respectively. Also, there is a negative and statistically significant relationship between these two variables (p<0.001, r= -0.329).

Considering the negative relationship between social support and missed nursing care, it is therefore suggested that managers increase the social support of nurses to reduce missed nursing care and improve the quality of nursing services.

This article proposes a paper-based microfluidic chip that can non-invasively measure glucose with optical detection technique using NIR. This paper chip is disposable, portable, low-cost, lightweight, and suitable for point-of-care and cost-effective tests. This paper chip is fabricated with a kind of photoresist that is used in the publishing industry called UV curable resin. This method is chip, simple, and suitable for mass production. This paper chip is used for measuring glucose non-invasively and an interface sensor is designed with an NIR technique that can measure glucose concentration between 60 to 500 mg/dl with voltage range of 630 to 730 mV.

The lack of water resources and increase in water demand are among the effective factors in the imbalance of the water resources in each region, and it is necessary to manage the proper use of available water resources in all activities. Water in the agricultural sector is one of the main factors of production, which should be conveyed by irrigation systems to the field level and made available for the plant roots. The necessity of macro-planning in water management and consumption imposes a comprehensive study of the amount of water consumed in the agricultural sector. Hence, this study was conducted with the objective of directly measuring and field-assessing the applied water, water productivity, and water footprint associated with the primary crops cultivated in Markazi Province, all managed by local farmers.

For this purpose, 141 farms were selected in the major production areas of the main agricultural and horticultural crops of Markazi province with the coordination of the Agricultural Jihad centers. Then, the volume of water applied was measured without interfering in the irrigation scheduling of the users. To do so, first, the flow rate of the water source (canal, well, aqueduct or spring) was measured with a suitable device (flume and meter) in each of the selected farms. Then, by carefully monitoring the irrigation schedule of the farm, including the time of each irrigation, the number of irrigation throughout the year, as well as measuring the area under crop cultivation, the amount of water used by the crop was measured for each of the selected farms during the season. Also, based on the measured data, the amounts of blue, green and gray water footprints were determined for each of the examined crops. For this purpose, the blue, green and gray water footprints of different crops were calculated using the framework provided by Hoekstra and Chapagain (2008), and Hoekstra et al., (2011).

The irrigation intervals in the studied fields varied between 3 and 15 days with an average of 8 days and the average irrigation depth varied between 26.2 and 99 mm with an average of 67.8 mm in different crops. The results showed that the average volume of applied water for the studied crops in Markazi province was 10782 cubic meters per hectare. Also, the minimum and maximum amount of applied water for the evaluated crops was as follows: barley 3783 and 7232, alfalfa 10382 and 19797, beans 8280 and 17840, watermelon 5333 and 7174, walnuts 4420 and 29600, almonds 3850 and 13932, peaches 6872 and 17727, cherries 7050 and 14645, pomegranates 7156 and 20790, and grapes 5937 and 18168 cubic meters per hectare. Furthermore, the average value of irrigation water efficiency index and water footprint was as follows: barley 0.46 and 1642, alfalfa 0.92 and 700, bean 2924 and 0.24, watermelon 9.37 and 117, walnut 0.1 and 6706, almonds 0.16 and 6857, peach 2.48 and 242, cherries 0.73 and 875, pomegranates 1.33 and 636, and grapes 11.2 and 322. Based on the obtained results, the average total water footprint index was equal to 2102 cubic meters per ton. On average, the almond with a water footprint of 6857 cubic meters per ton had the highest share in allocating the water footprint in the crop production of the province. Whereas, the lowest water footprint related to the watermelon with a water footprint of 117 cubic meters per ton. he average values of the irrigation application efficiency index, irrigation water productivity, and water footprint for the examined farms were 72.5%, 1.79 kg/m3, and 2,102 m3/ton, respectively. In summary, the results indicate that the combined volume of irrigation water and beneficial rainfall in the irrigated fields within Markazi Province surpasses the actual water demand of the crops. This underscores the substantial impact of irrigation management on water utilization in the region.

On average, the total volume of irrigation water and effective rainfall in irrigated fields and gardens in Markazi Province is more than the actual water requirement of the plant. In general, the results showed that irrigation management has a great impact on the amount of water use in the region. Based on the obtained results, considering that most of the farms and gardens receive water in an intermittent manner, in principle, no special attention is paid to the need for water and even effective rainfall, and the amount of water availability has the greatest impact on water consumption. Therefore, in order to reduce water consumption and improve water efficiency, it is suggested to manage the delivery of water to farmers during the season and according to their crop water needs. Also, the results of the water footprint can be used to improve water resource policies at the province level, land use studies, cropping pattern modification, and environmental sector policies.

The objective of the present study was to conduct field studies for direct measurement of canola under farmers' management in one crop season (2019-2020) in 27 farms in Behbahan, Khuzestan province. Water requirement was calculated based on the FAO Penman-Monteith model using the daily statistics of the Behbahan synoptic meteorological station. A T-test was used to statistically compare the results such as the depth of irrigation and applied water productivity in the field in different irrigation systems. Linear multivariate regression analysis was used to investigate the effects of the independent variable on the dependent parameter of water productivity. The volume of applied water in the fields ranged from 4085.5 to 7865.3 m3/ha. The results of comparing the average yield of two irrigation systems in the t-test showed that the two sprinkler and surface irrigation systems with yields of 2614 and 2330 kg/ha, respectively, were not significantly different. Applied water productivity in traditional and modern irrigation systems was calculated to be 0.386 and 0.486 kg/m3, respectively, which had significant differences. The results of the analysis of variance in the regression model showed that among the independent variables, yield with t-statistic (23.997) and equivalent beta coefficient (0.880) had the most significant positive effect at a 1% level on applied water productivity. After that, the volume of applied water (irrigation water + effective rainfall) with a t-statistic of (-11.702) and a beta coefficient of equivalent (-0.793) had the most negative and significant effect at the level of 1% on the applied water productivity. The results of the Pearson correlation coefficient showed that irrigation events had a positive and significant correlation at a 5% level with applied water and yield. These correlations were 0.455 and 0.380, respectively. By increasing irrigation events, the volume of applied water has practically decreased and has become as close as the plant needs, and has increased water productivity.

The present study was conducted in the research field of Seed and Plant Improvement Research Institute to investigate the effect of fertilizer amount in three levels (N1: 100, N2: 80, N3: 60 percent of fertilizer requirement) and two splitting methods (T1: four equal usage including 4-6 leaf stage, 10 leaf stage, reproduction stage and inoculation stage and T2: three equal usage including 4-6 leaf stage, 10 leaf stage and reproduction stage) on corn yield and yield components. The treatments were compared with control which is the common fertilizer usage in the region. Based on the results, the highest grain yield in the first year was obtained in T1N1, T1N3 and control treatments. Grain yield in T2 was less than T1. Nitrogen splitting in T2 compared to T1 reduced the nitrogen content and grain protein content by 12.8% and 13%, respectively. Splitting of nitrogen fertilizer in three stages caused more nitrogen uptake by crop leaves at the end of the growing season; however, this did not increase grain yield and seed quality. Except for the control, no significant changes in soil nitrogen content were observed from surface to depth. The highest percentage of soil nitrogen was observed in the two layers of 0-20 and 20-40 cm in the control. The lowest content of soil nitrogen was observed in in T2N3 treatment with 24.5% (0-20 cm) and 24.5% (20-40 cm) more than control, respectively. The highest and lowest nitrogen losses in runoff were observed in T1N1 (23%) and control (7%), respectively. With the reduction of fertilizer application, runoff losses also decreased; in the T1N2 and T1N3 treatments, this reduction was 9% and 14%, respectively. Overall, T1N2 is recommended as a suitable treatment due to the high grain yield, seed quality and reduction of nitrogen losses.

Epidemiological studies have indicated the prevalence of a wide spectrum of diffused pigment lesions throughout the world and Iran. The aim of this study was to determine the frequency distribution of oral diffused pigment lesions in patients presenting to Oral Diseases Department of Isfahan Dental School.

A cross-sectional descriptive study was conducted on 303 patients presenting to Oral Diseases Department of Isfahan Dental School during the first three-month period of 2019. The demographic data, location of lesions, and type of lesions were recorded in a checklist and analyzed with the SPSS version 22 using Chi square, Mann Whitney test, Fisher's exact test, and spearman correlation coefficient. The level of significance was set at 5%.

In this study, 303 patients were examined of whom 93 (30.69%) were diagnosed with diffused pigment lesions. As for the pigmentation severity, the patients were grouped into low, moderate, and high with 54 persons (58%), 13 persons (14%) and 26 persons (28%) in each group, respectively. The most frequent site was labial gingiva and the most common type was the physiologic type. The results showed that gender had no effect on the frequency distribution (P=0.09) but gender and age had significant effects on the severity of pigmentation (P=0.047, r=0.459 and P<0.001 respectively). Skin color had a significant effect on the type of pigmentation
(P < 0.001).

The frequency of oral diffuse pigmentation in patients presenting to the Isfahan dental school was noticeable.

Since 1995, Iran has been striving to liberalize its trade regime in order to increase its growth and trade performance. Despite a long period of liberalization, imports are still growing faster than exports, widening the trade deficit. Therefore, this study aimed mainly at investigating the effects of trade liberalization on the growth and trade of agricultural products using the Markov-switching model approach and annual time series data (from 1986 to 2018). The results showed that liberalization, by reducing the import tariff rate, increased exports by 1.56 percent in the short run, but reduced imports by about 7.65 percent in the long run. In addition, the results of growth pattern estimation showed that the liberalization index in both regimes had a significantly positive effect on agricultural growth, meaning that the implementation of trade liberalization policy in the studied period had a positive effect on agricultural growth by 1.98 percent. Thus, trade liberalization in the short run leads to growth in exports and in the long run, by increasing production, increases the volume of exports and decreases imports, and hence, leads to economic growth. According to the obtained results, in order to increase the trade potential of the agricultural sector, it is suggested that tariff policies on trade liberalization be developed in line with the objectives of the Perspective Document Programs of the country.

Recognizing the literary, critical and political features of the poems of poets such as the Third Brotherhood, including and fragmentation has always been prominent among researchers, but understanding these features in the light of an analytical method that allows the researcher to have a comprehensive understanding of how Representations of the protest poems of these poets can be found. In the present study, we try to study the methods of protest poetry in the poetry of poets such as the Third Brotherhood, including the fragmentation, with a comparative approach.

The method of this research is descriptive, documentary (library) and based on an analytical approach. In this method, the researcher tries to present his desired idea by using different methods of data collection.

The study of contemporary protest poetry methods based on the poetry of poets such as the Third Brotherhood and Shamloo and Siavash Kasraei indicates the unity of the conceptual and thematic system of the poems of these poets in the way of raising the voice of the people. Meanwhile, the Third Brotherhood speaks with a desperate voice about the length of Zoroastrian history and religion. Shamloo does not accept the established social order and in trying to understand an ideal system, it is political and social goals that gradually lead to a simple philosophical and revolutionary worldview. Kasraei, however, is not as disappointed with change as the Brotherhood, nor is he inclined to philosophical and social propositions, but he is a committed and revolutionary poet in every sense.

In the poetry of the Brotherhood, the themes of protest appear in the form of a kind of despairing attitude. The Brotherhood thought that the only way out was to take refuge in a genuine ritual. But Shamloo was inherently a poet incompatible with the spirit of his time. Shamloo's poetry considered all the vital elements of society to be a distorted structure of the ideological realms of political rule, and therefore considers protest in such a society a sacred movement. On the other hand, although Kasraei was close to Shamloo in terms of school and social ideology, but his primitive allegorical and symbolic approach and finally his revolutionary and guerrilla poems made him a supporter and encourager of a socialist and popular revolution.

The instability of the roof and walls of the tunnels excavated in coal mines has always attracted the attention of the miners and experts in this field. In this work, the instability of the main tunnels of the mechanized Parvadeh coal mine in Tabas, Iran, at the intersection with coal seam is studied. The main tunnels of this mine show significant horizontal displacements due to the complex ground conditions and great depth. The behavior of the rock mass surrounding the tunnel is investigated using various experimental methods, and according to the results obtained, the surrounding rock mass has squeezing conditions. In order to analyze the stability of the main tunnels, a series of 2D and 3D numerical modelings are performed using the FLAC2&3D finite difference software, and the results obtained are compared with the actual displacement values recorded in the walls of the main tunnels of the mine. The analysis results show that the tunnels under study are unstable with a steel frame support, and therefore, the use of different support systems for the stabilization is investigated. The results of modeling different types of support systems show that the use of shotcrete instead of galvanized sheet (as strut) does not have a significant effect on the reduced displacements. Also although the installation of steel sets is very effective in preventing the displacement of the walls, due to the swelling problems in the tunnel bottom and the placement of the conveyor and haulage rail, it cannot be used in practice. Finally, the use of truss bolt has yielded good results, and it can be proposed as a new support system in these tunnels. In addition, the modeling results show that in case the coal seam is higher than the tunnel foot, less displacement will occur in the tunnel walls compared to the other cases. In other words, changing the tunnel level in the future excavations can help reduce the displacements.

The process of guarantee of quality and evaluation of advancement of programs or effectiveness evaluation of progresses based on pre-set indicators is called ‘accreditation’. The accreditation program was run by Agricultural Engineering Research Institute (AERI) as one of the twenty research institutes affiliated to Agricultural Research, Education and Extension Organization (AREEO) of Ministry of Agriculture-Jahad (MAJ) in Iran. This institute is involved in four fields of ‘Irrigation and Drainage’, ‘Food Engineering and Post-harvest’, ‘Agricultural Machinery and Mechanization’ and ‘Greenhouse’. Thus, five working groups including ‘Missions and Objectives’, ‘Human Resources’, ‘Research’, ‘Education and Extension’ and ‘Budget and Credit’ were established and the tables of objectives and indicators, evaluation criteria, measurement indices, and achievement criteria were determined; then, six specialized questionnaires relevant to each working group (one questionnaire for each factor and two questionnaires for ‘Education and Extension’ factor) at the national level for 2014-15 activity years of the institute were given to the respondents and institute. The collected data were analyzed based on the Likert scale. The results indicated that the situation of the AERI status was satisfactory in the ‘Human Resources’, ‘Research’ and ‘Education and Extension’ aspects and unsatisfactory in ‘Missions and Objectives’ and ‘Budget and Credits’ aspects; in addition, the overall assessment of the institute was relatively satisfactory. Therefore, by benefiting more from the intellectual, skilled and collaborative efforts of AERI's faculty members as well as the attention of higher authorities, it is likely to strengthen the institute's strengths and eliminate its weaknesses to achieve a higher quality level. This study may serve as a good model for the other research institutes.

In this paper, a new simple direct method to solve nonlinear Fredholm-Volterra integral equations is presented. By using Block-pulse (BP) functions, their operational matrices and Taylor expansion a nonlinear Fredholm-Volterra integral equation converts to a nonlinear system. Some numerical examples illustrate accuracy and reliability of our solutions. Also, effect of noise shows our solutions are stable.

Sustainable agricultural development and national food security while preserving the health and the quality of crops depend on the development of knowledge-based agriculture. To advance knowledge-based agriculture, observing national and global developments in the future and coordinating its activities with the fluctuating changes in science and technology is the keystone. Due to the special position of research institutes in the achievement of knowledge-based agriculture, it is essential for these institutes to carry out the research based on scientific and technological world evolutions. So, in this research, alternative futures of the Agricultural Engineering Research Institute (AERI) considered as a knowledge-based research institute in the field of agricultural technology. The present study was based-on descriptive-analytical and survey methods. The statistical population of this research includes agricultural experts, researchers of AERI, agricultural managers, certified agricultural equipment producers, and beneficiaries. To collect data, a questionnaire, a library study and a panel of expert’s methods were used. Based on a literature review and panel of experts the questionnaires were designed in three steps, and their validity and reliability were measured. The GBN method was used to develop scenarios. In this research, the trend analysis was carried out. So, the driving forces affecting the future of AERI were identified. After determining the uncertainty of driving forces, the scenario matrix was determined and future scenarios of AERI designed. Three scenarios such as the common future, desired future, and hard-time future were designed based on the scenario matrix.

Because of decreasing the value and availability of water resources¡ we have to use water resources in a best way. The new irrigation systems like subsurface drip irrigation can improve irrigation efficiency and water use efficiency. To properly manage SDI systems¡ the precise distribution of water around the emitter must be known. Several models have been developed to simulate soil moisture pattern and wetting front by using soil hydraulicparameters¡ the emitter’s discharge and the volume of discharged water. In this paper¡ HYDRUS-2D model was used so simulation results were compared with two sets of experiments involving SDI with emitters installed at two different depth (40 &50 cm) while the emitters space was 75 cm with 3.5 l/h emitter discharge. The RMSE at different locations around emitter varied between 0.014 and 0.033 for volumetric water content in 40 cm installation depth and 0.009 and 0.025 for 50 cm installation depth. The continuous horizontal wetting profile was achieved so the space of emitter was suitable. With due attention to our results¡ 75 cm distance between emitters and 50 cm installation depth with 3.5 l/hr emitter discharge is proposed to be applied in loamy soil.

The presence of nitrate in water is one of the most important global concerns. Therefore use of cheap absorbents such as biochar and vermicompost is important as a solution environmental protection and management of crop residue. This study was conducted whit porpuse of compare of biochar and vermicompost sugarcane bagasse performance on nitrate removal from contaminated water and determines the optimum conditions for adsorption process. after providing of sugarcane bagasse biochar and vermicompost and determine of theirs characteristics, the effect of different parameter such as initial pH (2-11), dosage of adsorbent (1-10 g/L), solution temperature (10, 22 and 30 ° C), the presence of competing ions (phosphate, sulphate, carbonate and chloride) and contact time (0-180 min) was investigated on the efficiency of absorption. Then, different kinetic and isotherm models were fitted to the experimental data. The results of this study showed that the optimum pH of nitrate adsorption by sugarcane bagasse biochar and vermicompost was 4.64 and 3.78, respectively. Also optimum adsorbent dosage was obtained 2 gr/L. Among the competing anions, carbonate and chloride had the highest and the lowest impact on the reduction of nitrate removal and nitrate removal efficiency was increased as the temperature increases. According to kinetic experiment, equilibrium time for nitrate adsorption by biochar and was obtained 60 and 120 min, respectively. The higher removal of nitrate by biochar (73.7%) in compare to vermicompost (48%) was due to specific surface area, the amount of carbon and anionexchange capacity of sugarcane bagasse biochar is higher than vermicompost. The pseudo-second order adsorption kinetic model and Langmuir adsorption isotherm model showed the best fit to the experimental adsorption data.

Diagnosis of water management at the irrigation district level is required for therational modernization of the irrigation schemes and the subsequent increase in the efficiency of water allocation and application. The objective of this study is to evaluate globally in 3079 ha of land under modern irrigation system Hamody. The main district’s water inputs (irrigation، precipitation and canal releases) and outputs (actual evapotranspiration of crops، outflow surface drainage and canal seepage) were measured or estimated during the 1385 to 1388 hydrological years. The annual average water outputs were 16% higher than the corresponding water inputs، presumably due to canal seepage and lateral groundwater inflows from neighbor dry-land watershed. The district-level irrigation performance was poor (mean 1385-88 seasonal irrigation consumptive use coefficient- ICUC were equal 44%)، due to the low distribution (68%) and on-farm (53%) efficiencies for the 1385-88 irrigation seasons. Thus، despite the high volume of applied irrigation water، the actual district ET was 19% lower than the maximum achievable ET، indicating that the water-stressed crops yielded below their maximums. The evaluation by using neoclassical approach indicated that the values of net (0. 77) and effective efficiency (0. 65) were more than classical efficiency (0. 53)، in surface irrigation systems. The results obtained in this study showed that effective efficiency has suitable expression about irrigation management and method at farm scale، whereas net efficiency only considers concept of reuse of beneficial losses on spatial scale larger than the field. Potential reductions in water allocation were analyzed for three ICUC values (65، 75 and 85%) and two scenarios of modernization (I and II). In scenario I، where the aim was to achieve maximum ET and crop yields، water allocation could be reduced from 0 to 23% of the current allocation. In scenario II، where the aim was to achieve the maximum conservation of water under the actual ET and crop yields، reductions in water allocation would be much higher (from 31 to 47% of current allocation). Thus، significant volumes of water could be conserved in the rehabilitation of this district by increasing the distribution efficiency and، in particular، the onfarm irrigation efficiency.

Salvia leriifolia (Lamiaceae) is an endemic plant of Khorasan and Semnan provincewith medicinal, antioxidant and nutritional properties. Drought stress affects on plantgrowth and development. To study changes in proline content of S.leriifolia affectedby drought and also identification of suitable environment for drought experimentstwo separate experimental (completely randomized design) was carried out in soil andin vitro medium. MS (Murashige and Skoog) medium was used for in vitro culture.Experiment was carried out in five different levels of water potential including 0, -2,-4, -6 and -8 bar with 4 replicates. Pressure plates were used in the soil experiment andPEG (Polyethylene glycol) was used in the in vitro medium. Proline in the leaves wasmeasured after the plants reached four leaf stage. The results showed that with increasing drought stress, proline accumulation in leaves was increased. This increase in the soil experiment was more than the in vitro one. It can be concluded that proline accumulation is a good measure plant responses to drought stress. Results of experimentsconducted in in vitro are more accurate because it is easier to control the environmentalconditions. It is also of less experimental cost and more space saving criteria.

The scarcity of irrigation water and decrease of water resources are the most important limiting factors in crop production in countries such as Iran. Thus, studying the optimum use of water and increasing water use efficiency are essential to the agricultural sector. The use of a low pressure hydroflume has been suggested to replace traditional surface irrigation methods. The aim of this research was to compare water distribution in the hydroflume with traditional and sprinkler irrigation systems. Farms in the Kabodarahang plain were selected for the evaluation of water consumption, yield, irrigation efficiency and water productivity. The results showed that most water loss in the farms irrigated by hydroflume was deep percolation and, in the farms irrigated by traditional furrow irrigation, was runoff and deep percolation. The amount of runoff loss in the traditional and hydroflume methods were 25.8% and 15%, respectively. In the hydroflume method, the average of potential efficiency of low quarter was 50, application efficiency of low quarter was 48.2, distribution uniformity was 79.2, and uniformity of the Christiansen coefficient was 77. These parameters for the traditional method were 44.8, 34.9, 87.65, and 89.1, respectively. For the sprinkler method, they were 57.6, 56, 70.3 and 76.6, respectively. The water productivity for the traditional, hydroflume and sprinkler irrigation systems were 1.2, 2.4 and 3.2 kg/m3, respectively. The venue of hydroflume irrigation relative to traditional irrigation increased by 39376600 rails/ha. The ratio of benefit per cost in hydroflume irrigation systems was 6.

In this study, with measuring water uptake in different soil layers, the role of different parts of root system in crop water supply during water stress conditions is characterized. Four cylindrical lysimeters with 25 cm diameter and 100 cm height were filled with clay loam soil. Soil columns were separated to 4 layers with 3 cm sand layers. Subsurface irrigation was applied with water stress patterns (decreasing number of layers which were irrigated from subsurface). Sand layers in each column which were preventing soil moisture exchange, could characterize the real role of each sub-layer root in water uptake when surface layers were under water stress. In this study root water uptake equation is corrected for water stress condition with presenting a compensation factor. With this corrected equation root water uptake in soil layers under water stress condition is investigated. The results showed that corrected equation determined root water uptake better than other equations in some conditions. Compensation factor is dependent on a plant factor (), that was determined with inverse optimization technique from root water uptake data in each lysimeter (it is calculated as 1.1, 1.87, 2.23 and 2.38 for lysimeters 1, 2, 3 and 4, respectively). This factor increased with increasing water stress severity.

Water and nitrogen are the main limiting factors affecting agricultural production in arid and semiarid regions. Therefore, improving the efficiency of these factors is very important. The method of fertilizer application is affecting water and fertilizer use efficiency. The objective of this study was to investigate the effect of furrow fertigation on fertilizer use efficiency (FUE), water use efficiency (WUE), and corn yield. A field experiment was carried out in furrows which have 165m length and 0.006 (m/m) slope in Karaj. The corn Hybrid 370 double-cross was planted on June 2008. A factorial design based on randomized complete block design with 4 replicates. Four levels (0, 60, 80 and 100%) of the recommended fertilizer value and four levels (60, 80, 100, and 120%) of the irrigation water requirement were applied. These 16 treatments were compared with traditional fertilizer application method. Fertilizer treatments were accomplished in four critical stages of the growth (before cultivation, in seven leaves stage, shooting stage and Flowering stage) for fertigation treatments and two stages (before cultivation and seven leaves stage) for the traditional method. Results showed that effects of levels of different water and fertilizer on yield component were significant. Water use efficiency (WUE) was significantly affected by nitrogen rate. On the other hand, water treatments significantly affected fertilizer use efficiency. Increasing fertilizer increased water use efficiency. Increasing water levels to 100% of ETC resulted in increasing fertilizer use efficiency. Highest yield was obtained from the full irrigation treatments (W100%). Albeit the difference among W120%, W100% and W80% was not significant (P=0.05), because W100% was always higher than W120%, treatment of W80% recommends as optimum water level for arid and semi arid region. The maximum and minimum WUE was 2.24 and 0.66 (kg/m3) in W80%N100% and W100%N60%, and The maximum and minimum FUE was 29.85 and 8.52 (kg/kg) in W100%N100% and traditional method, respectively.

Estimation of unsaturated soil hydraulic and solute transport properties by Inverse modeling has thus far been limited mostly to analyses of one-dimensional experiments in the laboratory, often assuming steady-state conditions. This is partly because of the high cost and difficulties in accurately measuring and collecting adequate field-scale data sets, and partly because of difficulties in describing spatial and temporal variability in the soil hydraulic properties. In this study we estimated soil hydraulic and solute transport parameters from several two-dimensional furrow irrigation experiments under transient conditions. Three blocked-end furrow irrigation experiments were carried out, each of the same duration but with different amounts of infiltrating water and solutes resulting from water depths of 6, 10, and 14 cm in the furrows. Two more experiments were carried out with the same amounts of applied water and solute, and hence for different durations, on furrows with water depths of 6 and 10 cm. The saturated hydraulic conductivity (Ks) and solute transport parameters in the physical equilibrium convection-dispersion (CDE) and physical nonequilibrium mobile/ immobile (MIM) transport models were inversely estimated using the Levenberg-Marquardt optimization algorithm in combination with the HYDRUS-2D numerical code. Estimated Ks-values ranged from 0.0389 to 0.0996 cm min-1, with a coefficient of variation of 48%. Estimated immobile water contents (θim) were more or less constant at a relatively low average value of 0.025 cm3 cm-3, whereas the first-order exchange coefficient (ω) varied between 0.10 and 19.52 min-1. The longitudinal dispersivity (DL) ranged from 2.6 to 32.8 cm, and the transverse dispersivity (DT) from 0.03 to 2.20 cm. DL showed some dependency on water level and irrigation/solute application time in the furrows, but no obvious effect was found on Ks and other transport parameters. Agreement between measured and predicted infiltration rates was satisfactory, whereas soil water contents were somewhat overestimated and solute concentrations underestimated. Differences between predicted solute distributions obtained with the CDE and MIM transport models were relatively small. This finding and the value of optimized parameters indicate that observed data were sufficiently well described using the simpler CDE model, and that immobile water did not play a major role in the transport process.