فهرست مطالب میر خالق ضیاء تبار احمدی

Due to drought crisis in recent years, the use of alternative cropping methods that saves water without any decrease in yield is increasing. Regulated deficit irrigation is a method of irrigation in which, by supplying part of the maximum crop requirement at specified times, water management is addressed and therefore the root zone is in a dry area most of the time. Using this method will partially stop the growth of the plant and usually decrease yield (Jovanovic et al., 2010). Root Partial Drying (PRD) is a modified form of the deficit, which includes watering one section of the root zone in each irrigation and dry up another side, so the moisture of this section before next irrigation largely come down (Ahmadi et al., 2010). In the root drying method, the roots of the plant simultaneously with soil drying with the production of Abscisic Acid, prevent leaf expansion and reduce stomatal conductance. Simultaneously with this process, the root in the wet part with adequate water uptake puts the plant in proper moisture (Yousri Ibrahim Atta, 2008). Abscisic acid is a plant hormone whose production is increased by root in dry soils and transported by water flow into the stem. (liu et al., 2008). On the other hand, The quality of production is as important in all crops and especially in rice production in Iran. (Salehifar  et al., 2009) In order to evaluate some of the physical and qualitative properties of rice grain and the amount of nitrogen uptake in rice (Hashemi variety) under different irrigation levels and comparing it with continuous waterlogging, an experiment was conducted during two years of cultivation of 2015 and 2016.

Due to the increased water consumption and the depletion of water resources, deficit irrigation is an optimal strategy for cultivation, which is usually applied by utilizing the methods of Deficit Irrigation (DI), Regulated Deficit Irrigation (PRD), and Partial Root-zone Drying Irrigation (PRD). In the PRD method, just one side of the plant is irrigated in each irrigation interval. Under these conditions, in the part of the irrigated plant, the roots absorb enough water and grow, so that there is no change in the amount of the plan’s photosynthesis. There are some models, including WOFOST (Van Diepen et al., 1989; Boogaard et al., 1998), EPIC (Jones et al., 1991), AquoCrop (Steduto et al., 2009), and STICS (Brisson et al., 2003), that can simulate crop yield under different soil conditions, Climates, irrigation schedule, and agricultural managements (Hashemi et al., 2018). These models simulate PRD irrigation, such as the DI method. Daisy is the first model, differentiating the gained results between the two methods (Hansen et al., 1990; Hansen et al., 1991); a semi-experimental model that considers the Richards equation (Richards, 1931) to simulate the soil water content and the experimental equations to simulate crop yield parameters. The PRD sub-model in the Daisy was developed and upgraded based on the data gained from potato cultivation under PRD irrigation (Liu et al., 2008; Plauborg et al., 2010). Since this sub-model was developed only for the potato, the aim of the present study was calibration and validation of two parameters; stomatal slop factor (m) and specific leaf weight modifier (LeafAIMod) in the PRD sub-model, to run the Daisy model to simulate sunflower under the PRD irrigation.

The present study was conducted to investigate the effect of three rice cultivation systems including traditional flooded cultivation, improved cultivation and system of rice intensification (SRI) with different irrigation regimes on water productivity, yield and yield components of Hashemi and Kuhsar cultivars in the first and second crops. It was done in factorial in the form of a randomized complete block design in two cropping years of 2016-2017 and 2017-2018 of Mazandaran province in Iran.  The results showed that the effect of these three cropping systems on the number of seeds per panicle, number of full and empty seeds, grain yield, plant height, cluster length, water requirement and plant evapotranspiration was statistically significant at 1% level. The highest amount of irrigation-based productivity with a value of 2.24 for Kuhsar cultivar in the second crop (intensive rice cultivation management) and the lowest amount for Kuhsar cultivar in the first crop (traditional flooding system) with a value of 0.66 kg / m3 Kg of paddy per cubic meter of water was allocated. The results showed that the use of improved and intensive rice cultivation management systems increases water productivity and therefore can be one of the recommended solutions to officials and farmers in rice fields. Due to the increase in plant growth period in the intensive rice cultivation management system due to the young age of the plant and the possibility of its collision with the cold season and a significant reduction in yield, its use in the second crop, especially when delayed transplanting is not recommended. Be.

The purpose of this study was to investigate the effects of irrigation management on water requirement and crop coefficient of Hashemi and Kuhsar cultivars in the first crop. This experiment was carried out in Mahmoudabad District of Mazandaran Province in Iran in the form of factorial in a randomized complete block design, in two growing seasons of 2016-2018. The water requirements for the fields (from transplanting to harvest) and the crop coefficient of these two cultivars were studied in two systems of traditional flooding and system of rice intensification (SRI).  The results showed that, in the first crop, the two-year average water requirements of Kohsar and Hashemi in SRI were 534 and 556 mm and for the traditional flooding system 623 and 632 mm, respectively. The water required by the farm in traditional flooding decreased by 13.1% in the SRI. Based on reference evapotranspiration using pan evaporation method for the three stages of vegetative, reproductive, and maturing, crop coefficient values for the flooding system for Kuhsar were, respectively, 1.14, 1.29, and 0.92; and for Hashemi, they were 1.18, 1.32, and 0.92. According to the obtained results, SRI causes significant savings in paddy water consumption, therefore, it is suggested that, due to water shortage in the country, this method be used as one of the adaptation strategies in rice fields.

Using the simulated models can help the users to approach the attitude of applying different managements. Therefore, identifying and evaluating the models in this case is non-negligible. The Daisy model is one of the most comprehensive models for simulating of the water-soil-plant-atmosphere system whose performance was evaluated in this study. Based on the data of three irrigation treatments: Full irrigation (FI) and deficit irrigation (DI) at 75% and 55% level during two years, the conditions were defined in the model and the crop submodel was made for the sunflower. The yield parameters were measured and compared with simulated values based on R2, NRMSE and efficiency coefficients (EF). The model was validated based on the results of full irrigation treatments and the model performance was also evaluated based on irrigation treatments. The results showed that Daisy has a very acceptable performance by the mean of NRMSE for the leaf area index(LAI), height(H) and dry matter(DM) and water content estimated 0.059, 0.036, 0.031 and 0.064 and the mean EF were equal to 85.67, 33.82, 91.5 and 67 percent. the rang of R2 was 0.799-0.999. The significance of the difference between simulated and observed values was compared by T-test for the paired samples in SPSS. The total results showed that the model could simulate the full irrigation better than the deficit irrigation. In general, Daisy could be used as an applied model to simulate the conditions of irrigation projects under different management.

Localized irrigation methods can be used to manage low water holding capacity in the sandy soils. In this research, the effects of different irrigation systems including pot, tape and drip irrigation with gravity pressures of 0.5, 1.5 and 3 meters on the sandy soil moisture distribution under watermelon cultivation were compared with the furrow irrigation as the control treatment. The moisture content of the soil at different depths and at the distance of 5 and 20 cm from the plant was measured using the TDR device. Water distribution study showed that in the pot irrigation method, the moisture content of different depths of soil was kept constant by 16% during the irrigation interval, but the highest moisture content was observed in gravitional drip irrigation treatment at the depths of 40, 50 and 60 cm; in contrast, the lowest amount of moisture was observed in the pot irrigation treatment. In tape and gravitional drip irrigation system with gravity pressure, in addition to the adjustment soil moisture up to 15 to 22% within the wetting front, soil moisture can be kept almost constant by pulsed irrigation technique. Therefore, while providing the use of drip irrigation system with minimum water pressure available in most of the agricultural land (0.5 m), using pot irrigation can ensure sandy soil moisture retention and soil for the cultivation of fruits such as watermelon plants.

The use of commonly known irrigation methods (especially surface irrigation or even irrigation under pressure) is limited due to the specific physical characteristics of keeping moisture and lowering the water holding capacity. In sandy beaches or desert plains (called sandstones) with mentioned physical characteristics. lack of nutrients necessary for plant growth restrict the commonly known irrigation application. Gravity Drip Irrigation (GDI) is a new method that avoids the use of extra energy (pumping station). The total amount of pressure head required by the GDI for fields with a maximum area of 100 hectares is between 1 and 3 meters height. The main purpose of GDI is to reduce the required pressure by the drippers. The utilization of drip tape irrigation as one of the GDI methods has been considered in Iran in recent years. Several studies have been carried out in this regard, each of which pursues specific goals. The GDI benefits includes: reducing water consumption per unit area while increasing the moisture content of the plant root zone, increasing water use productivity, the possibility of irrigation in uneven terrain, reducing weed, pests and diseases damage, ease of distribution of fertilizer, requires lower pressure which consequences to lower cost and energy in the production process. Pot irrigation method is one of the most effective methods for irrigating in these conditions with rough terrain, coarse texture and light soils with high water penetration and saline water which surface irrigation methods normally cannot be used. The application of methods that can provide optimal irrigation conditions for such soils with their specific characteristics, such as delay in water infiltration and low outflow, can lead to improved physical conditions and optimal management of these soils. This research was carried out in the first four months of 2016 in a sandy field located in a part of the agricultural land of Jihad-e-Tavan Co. in Kashan city. In this research, according to the custom of the region, the local watermelon of Sunbek district in Aran and Bidgol city, were chosen as a study plant. A factorial design in a completely randomized block including three main treatments of localized irrigation and three irrigation treatments (total of nine treatments) with three replications, as well as furrow irrigation treatment as control were applied. In each row, 12 plants were planted with a distance of one meter on a row and three meters between rows, on an area of 1080 (36×30) square meters. The role of pulsed irrigation cycle in providing favorable growth conditions and consequently increasing yield can be achieved by comparing the performance of localized treatments and control treatment. The Duncan's test results for number of fruits and yield comparison using selected irrigation methods showed that there was no significant difference in the number of watermelons and their weight at the probability level of 1% and 5%. For different irrigation methods, there was a significant difference between yield and number of watermelons at same probability level. By the end of the 110 days after planting, the yield in furrow irrigation, pot irrigation, drip tape and GDI were 11426, 1224, 7527 and 11457 kg/ha, respectively. The improvement percentage of yield in comparison with the control treatment, were 85%, 1034% and 1626% in pot irrigation, drip tape and GDI, respectively. This research results revealed that the ratio of water used to yield in furrow treatments, pot, drip tape and GDI were 1.18, 5.55, 0.9 and 0.09 m3/kg. Also, considering the amount of water used for each treatment, 49.7 and 23.4 percent decrement in applied water in drip tape and GDI and 371.2 percent increment in applied water in pot irrigation observed per kilograms of watermelon produced compared to the conventional irrigation method (furrow irrigation). Highest water productivity index achieved in GDI among the four methods studied, as much as 1.7 kg of watermelon produced per cubic meter of water. In this study, the efficiency of more than 80% achieved in furrow irrigation in sandy soil. Improvement in irrigation efficiency in these soils can be achieved by managing parameters involved like furrow length, time and irrigation discharge. The results showed that with the amount of water consumed equal to 6790 cm3/ha in each of the gravity localized irrigation methods and 13452 cm3/ha in the control treatment, the watermelon yield in pot irrigation, gravity drip, drip tape and furrow irrigation methods were 1224, 11457, 7527 and 11426 kg/ha, respectively, and the water productivity index was equal to 0.2, 1.7, 1.1 and 0.8 kg/ha.m3, respectively. In comparison with the one-day irrigation interval, using pulses irrigation in localized irrigation, irrigation efficiency increased from 87% to 98%. In general, by using localized irrigation in comparison with furrow irrigation in sandy soils, in addition to increasing water productivity, high yield could be achieved in plants like watermelon.

Increasing of water demand, drought and climate changes, the development of contaminated resources, in addition to the threat of the ecosystem, affects the supply of drinking water and agriculture. The use of QUAL2KW as a qualitative numerical simulations model, water quality parameters changing such as dissolved oxygen (DO), biological oxygen (CBODu), acidity (pH), electrical conductivity (EC), nitrate (NO3-) and phosphate (PO43-) had studied in Talar River. The accuracy of predicted DO and pH parameters is better than the others. The most accurate simulation was occurred with the lowest coefficient of variation mean square error (0.017) and mean square error (0.139 mg/l) of pH parameter in February and also lowest accuracy in the simulation with maximum coefficient of variation mean square error (0.45) and mean square error (4.5 mg/l) of BODu parameter in November and most changes in the trend chart occurred in Ghaemshahr and Kiakola output Which could be due to the impact of the waste water coming from the two cities into the river. In general, the results of the river's simulation showed that the qualitative model QUAL2KW gives proper estimation of the river's quality conditions

Regulated Deficit Irrigation (RDI) is the strategy of reducing irrigation rates, during a specific period of growth and development, with the objective of conserving water and managing plant growth while maintaining or improving yield and quality. Partial root zone drying (PRD) is a possible irrigation technique that deliberately exposes the plant to water deficits to induce physiological responses that can improve the efficiency of water use. It involves irrigating only one part of the root zone in each irrigation event, leaving another part to dry to certain soil water content before rewetting by shifting irrigation to the dry side.
Various plants are different in economic efficiency of irrigation water used. Medicinal plants, as a collection of plants with high economic value, can produce more capital than other plants in terms of water scarcity. The objective of this study was to determine the response of peppermint yield components, oil yield, and water use efficiency to regulated deficit irrigation and partial root-zone drying in field condition.

The main purpose of irrigation and partial root zone drying is to overcome soil moisture deficit in root zone for plant use and water saving, respectively. In addition, one of the soil amendments to increase soil fertility is biochar, which affects the amount of water abstraction in the root zone. The aim of this study was to evaluate the effect of partial root zone irrigation of maize under different level of biochar (6 and 12 ton ha-1) on the moisture characteristics and soil water content of loamy texture. The project was done in Ahmadabad Mostofi research farm in Tehran. This project was complete block design under split plot with three replicates. The results showed that full irrigation treatment had the highest amount of soil saturation moisture and available water, which had a significant difference with partial root zone irrigation (PRD) treatments. On the other hand, in the soil of PRD, under low matric potential and near saturation level, the maximum of soil moisture content was related to 12 ton per ha treatment of biochar. In addition, this treatment had the highest amount of available water and water content that were 24 and 15 % and 18.6 and 9.8 %, respectively, higher than 0 and 6 ton ha-1 biochar treatments. Therefore, the biochar can effectively improve the soil ability to maintain water. This condition has improved the maize yield under partial root zone irrigation.

Water demand is one of the most effective factors in irrigation scheduling. In evapotranspiration formulas, crop coefficient (Kc), as a representative of different plants characteristics, is of great importance. Calculating this coefficient using the existing methods and formulas is costly and time-consuming, and results are point-specific. However, nowadays, calculation methods that provide large- scale Kc values are of interest. The methods based on remote sensing have been welcomed by many researchers. The objective of the present study was calculating crop coefficient (Kc) and leaf area index (LAI) of rice in different growing stages, using OLI sensor. In this regard, data LAI of two rice fields (areas of 15 and 65 hectares) located in north part of Sari, Iran, were used in two growing seasons (2014-2015 and 2015-2016). The average Kc at transplantation, tillering, heading, and maturity stages was, respectively, 0.92, 1.24, 1.19, and 1.12, showing that Kc had a good correlation with NDVI at different stages (r>0.97). According to the results, NDVI is a good estimator for rice Kc. In addition, Rice Growth Vegetation Index (RGVI) in all growing stages had a correlation coefficient r>0.93. RGVI is considered as a good estimator of LAI. Approximately at all growing stages, except heading, more than 93% of LAI changes were predicted by RGVI. Generally, it can be concluded that the most suitable indices for estimating Kc and LAI of rice are NDVI and RGVI, respectively.

Due to drought crisis in recent years, the use of alternative cropping methods that save water without any decrease in yield is increasing. Therefore, in order to evaluate the yield, yield components, and water use of rice under different non-submerged water levels and comparing it with permanently submerged condition, an experiment was conducted at fields of Rice Research Institute of Mazandaran during 2015 and 2016, using a randomized complete block design with three replications. The treatments consisted of two methods, regulated deficit irrigation (RDI) by irrigating all furrows and partial root drying (PRD) by irrigating alternate furrows, with three levels of drought stress: 10, 30, and 60 KPa (RDI10, PRD10, RDI30, PRD30, RDI60, PRD60) and a control treatment with permanently submerged basin irrigation in puddled soil (traditional method). Rice yield, yield components, and water consumption were measured in each treatment. The results showed that yield, plant height, panicle length, number of grains, 1000-grain weight, and water productivity (kg/m3) and water consumption at different levels of irrigation had a statistically significant difference in different treatments. Although the highest yield of rice was obtained in continuous submergence, yield reduction in alternate furrow irrigation treatments with minor stress (RDI10 and PRD10) was negligible and they were in the same statistical group in the two years of study. Also, partial root drying, significantly reduced water consumption, such that PRD10 treatment resulted in 32% reduction in water consumption compared to the control treatment, and deficit irrigation, especially partial root drying, increased water productivity. The highest water productivity (kg/m3) was calculated in PRD30 treatment at 0.724 kg per cubic meter of water. Based on the results, water consumption in the partial root drying was less than regulated deficit irrigation with the same tension, such that water consumption in PRD10 decreased by 15% compared to RDI10. However, average yield of PRD10v in both years was 1.1% higher. The results related to the yield components were also proportional to yield and partial root drying method compared to regulated deficit irrigation was better.

Deficit irrigation as a tension producing factor effects on vegetative and physiological characteristics of plants. In order to investigate the effect of the amount of irrigation water and the method of applying deficit irrigation practices on the yield, quantitative and qualitative parameters a Hayward cultivar Kiwi, experiment was made on of Hadishahr (5 kilometers from Babolsar) with 5 treatments and 3 replications during 2 growing years. The treatments under investigations were full irrigation (100% water consumption requirement), deficit irrigation (DI) at 2 levels of 60% and 70%, partial root drying irrigation (PRD) at 2 levels of 60% and 70%, respectively. Investigations of the effect of treatments was measuring quantitative and qualitative measurements of fruit samples including: volume, fruit size in different directions, fresh and dry weight, moisture content, treatable acidity and soluble solid materials in each processing stage. The amount of water consumption of irrigation treatment in full irrigation in total growing season and applying deficit irrigation were 239 and 141 mm, respectively. The water savings in deficit irrigation treatments were respect to total irrigation at the level of 70% was 15.33% and 25.26% in the whole period of irrigation and the duration of applying irrigation treatments, and 16.79% and 25.75% respectively in irrigation treatments. Based on the mean comparison between irrigation treatments in harvesting stage, the effect of treatments on fresh and dry weight, volume and Y dimensions were meaningful but not in X dimension, soluble solid materials, moisture content and dominant fruit acidity. The results indicate that applying deficit irrigation treatments not only improve fruit quality, but only is an approach for improvement of water crisis and reaching a sustainable agriculture.

According to the Statistical Center of Iran, the country's population between 1957 and 2017, has increased approximately from 19 people to 80 million. With population growth, the water demand is increased and water resources are threatened cumulatively. Agriculture is recognized as the main water consumer in the country. Due to the arid and semi-arid climate of the country, it is essential to use water reduction strategies such as deficit irrigation (DI) and partial root zone drying (PRD) deficit irrigation in agriculture. In case of water shortages, DI is an optimal solution for production, which is usually accompanied by a reduction in product per unit area. The base of PRD is keeping dry the half of root while irrigating the other half. The plant root in the wet area absorbs enough water. The other part of the root in dry soil, with a reaction to dryness and sending symptoms to the stomata, affects their opening size and reduces water losses. Sunflower is one of the four major oil producing plants in the world. The high volume of this product's import causes the country's strong dependence on oil import and the currency's outflow from the country. Although all living and non-living stresses are considered to be major factors in reducing production, water deficit stress is one of the main factors limiting the production of sunflower; Therefore, studying the reaction of this plant to different drought stress conditions and providing a solution to reduce the negative effects of dryness would be essential.

The present study was conducted on sunflower plant (Hysun 25) in a research farm of Sari Agricultural Sciences and Natural Resources University (SANRU) in 27 plots (5 × 5 square meters). Each plot consisted of 6 rows of planting at a distance of 75 cm from each other and 5 meters long. Sunflower seeds were planted at a depth of 4 cm from the soil and at a distance of 20 cm from each other. The experiment was conducted by using split-plot design, with three main factor (irrigation interval) and three sub-factor (irrigation water amount) in randomized complete block design in three replication. The irrigation intervals were irrigation after 20, 35 and 50 mm evaporation from class-A evaporation pan (F-20, F-35 and F-50 respectively). The sub-factor was irrigation water in levels of 100%, 75% and 55% of water demand (FI, PRD-75 and PRD-55 respectively). Controlling the volume of water delivered to each treatment was carried out using a volumetric flow meter. The application of irrigation treatments was carried out six weeks after planting. The irrigation for FI was conducted regularly at both sides of the root and for PRD it alternatively changed at the right and left sides of the root. The studied traits were irrigation water use efficiency (IWUE, kg/m3), height (H, cm), the flower diameter (D, cm), the seeds number per flower (SN), the 1000 seeds weight (W, gr) and the chlorophyll index (SPAD). Statistical analysis of data conducted by SAS software using Duncan test (1% level). Diagrams extracted by Microsoft Excel software.

Evaluation of irrigation interval factor based on the experiment two years data, indicated that the best results for plant growth parameters was for F-20. Also, the best results for sunflower plant growth parameters was for FI. According to the significant difference between FI and PRD-55 at most of the growth parameters, it’s suggested to conduct PRD-75 for PRD. For the irrigation interval factor, there was significant difference for most of the plant growth parameters between F-20 and F-50. Therefore, considering this case as well as the problem of increasing the operating cost by reducing the irrigation interval, F-35 is recommended for irrigation interval. It’s concluded that there was significant difference between all of the irrigation interval treatments by analyzing the IWUE trait. The highest amounts was for F-50 and the lowest was for F-20. Despite the increase in the value of IWUE in PRD-75 in comparison with other treatments for each two years of the experiment, this difference was not significant. According to the non-significant difference between F-35 and F-50 for IWUE at the second year of the experiment and this trait relative increase at PRD-75 in comparison with two other treatments, it’s suggested to conduct PRD-75 with F-35 to have higher IWUE.

Simultaneous analysis of sunflower’s IWUE and its growth parameters showed that it could be possible to save in irrigation water use and increase the IWUE with the lowest decrease in the sunflower plant growth parameters by applying PRD-75 and F-35.

The current study was conducted at Sari county prior 2015 and 2016 seasons with split plot design with three main factors (irrigation interval) and three sub main factors (irrigation water amount) in a complete block design in three replications. The irrigation intervals were irrigation after 20, 35 and 50 mm evaporation from class A evaporation pan (respectively F-20, F-35 and F-50). The statistical analysis of data was conducted by SAS software using Duncan test. Due to the non-significant difference for seed performance (SP) trait between FI and PRD-75 treatments, it could be possible to save approximately 13% of water by applying PRD-75. The F20-FI and F20-PRD75 treatments had the best results for SP respectively. F20-PRD75 and F35-FI had the best results for oil performance.

In order to reduce water and chemical fertilizer consumption and improved nutrient uptake in a maize field in Sari Agricultural Sciences and Natural Resources University this research were carried out during years 2015 to 2016. Main plot consisted of irrigation treatment (Full irrigation (FI), deficit irrigation (DI) and partial root zone drying irrigation (PRD)). Sub plot consisted of fertilizer treatment (chemical fertilizer (T1), 50% chemical fertilizer 5.5 tons per ha of vermicompost (T2) and 11 tons per ha of vermicompost (T3)). The result showed that the simultaneous application of PRD and vermicompost save more water. The effect of irrigation treatment on N, P, K, Fe, Zn and Mn was significant but no significant on Cu. The effect of fertilizer treatment on N, P, Fe, Cu, Zn and Mn was significant but no significant on K. There was no significant effect between PRD and T2 treatment with FI and T2 treatment on concentrations of nutrients and yield. Therefore, simultaneous use of partial root zone drying with vermicompost in combination with chemical fertilizers is recommended to achieve sustainable agriculture.

Using soil moisture storage techniques, simultaneously with irrigation management practices play an important role in coping with the problem of water shortage and water crisis. Therefore, the aim of this study was to evaluate the simultaneous effect of partial root zone drying and vermicompost on the water use, yield, biological yield, harvest index and leaf relative water content (RWC) of maize in sari.
The experiment was arranged in split plots based on complete randomized block with 3 replications were carried out during years 2015 to 2016. The experiment treatments were full irrigation and chemical fertilizer (FIT1) as control treatments, full irrigation and 50% chemical fertilizer 5.5 tons per ha of vermicompost (FIT2), Full irrigation and 11 tons per ha of vermicompost (FIT3), deficit Irrigation and chemical fertilizer (DIT1), deficit irrigation and 50% chemical fertilizer 5.5 tons per ha of vermicompost (DIT2), deficit irrigation and 11 tons per ha of vermicompost (DIT3), partial root zone drying irrigation and chemical fertilizer (PRD1), partial root zone drying irrigation and 50% chemical fertilizer 5.5 tons per ha of vermicompost (PRD2), partial root zone drying irrigation and 11 tons per ha of vermicompost (PRD3); while in DI and PRD 65% water of FI was irrigated. TDR access tubes were installed in the soil profile to measure soil water content.
The results showed that the effect of irrigation treatments was significant on all physiological parameters considered in this study. The effect of fertilizer treatments was significant on all parameters except RWC. The highest yield was attained in FIT2 treatment, equal with 8 and 8.2 tons per ha in 2015 and 2016, respectively. The PRD treatments was caused to significant increase in yield, biological yield and RWC compared with the DI treatment. The use of vermicompost in combination with chemical fertilizer increased yield, biological yield and harvest index. Vermicompost increased RWC was compared to chemical fertilizer.
simultaneous use of PRD and vermicompost was saved more water (26.3 %) than using them separately. Compared with FIT2 treatment was no significant difference in the values of yield and other physiological parameters of maize. Therefore, PRD2 is recommended to compatibility with the problem of water shortage. simultaneous use of PRD and vermicompost was saved more water (26.3 %) than using them separately. Compared with FIT2 treatment was no significant difference in the values of yield and other physiological parameters of maize. Therefore, PRD2 is recommended to compatibility with the problem of water shortage.

Practical problems such as rushing roots toward pot, difficulty of manually filling with water and deficit irrigation due to permeation from regular pots prevents the development of pot irrigation. With regard to increasing irrigation efficiency importance and preventing water loss to fix the problems of this irrigation method.Changing physical structure of pot could solve many problems and issues which this irrigation technique is facing. Comparison of the two major characteristics of localized irrigation hydraulic characteristics (coefficient of variation and distribution uniformity) and also using gravity pressure can achieve a solution for water and energy shortage problems. So far, with knowledge of the role of water pressure at gravitational pressures in hydraulicproperties of these methods, some effective features in these methods application is specified.
Material and This study was carried out in randomized complete block at water engineering department of Sari Agriculture Science and Natural Resources university laboratory from September to December 2015. In this study, in the form of randomized complete block, hydraulic specifications of three treatments of pot irrigation, gravity drip irrigation and porous pipe irrigation investigated under water pressure of 0.5, 1.5 and 3 m. In each of the water column pressure, output water volume from 10 samples of each irrigation method treatments calculated from 7 replicates during one hour in about two months. Porous pipes which used in this study were imported 16mm sample pipes from Anahita Company. GDI gravitational emitter model, porous pipe and containers made of cellulose clay pots in the form of cylinder shape with diameter of 15 cm were used. Thus, within one hour of irrigation, water volume withdrawn from tested samples under constant pressure of irrigation were collected by suitable containers and measured by graded container and flow rate of each samples were calculated. Christensen distribution uniformity coefficient was calculated with Christensen distribution uniformity coefficient formula. Based on USA agronomical engineers, a pointed emitters with variation coefficient less than 0.05 is good, with cv of 0.05-0.10 is medium and with cv of 0.10-0.15 is weak. After calculating evaluation parameters, the results were analyzed with SPSS statistical software and Tukey test at 1 %and 5 % level of probability.
The results of statistical analysis of randomized complete block design and mean comparison of different level of treatments effects with Duncan test (irrigation method treatment and water pressure treatment) at 5 %level of probability showed that maximum distribution uniformity achieved in gravitational drip irrigation among samples. With increasing pressure, coefficient of variation was less affected and at lower pressures, coefficient of variation among tested samples were more evident. In addition, it is indicated that increasing pressure have maximum effect on flow rate and distribution uniformity increment while with increasing pressure, minimum changes observed in coefficient of variation. Therefore, among possible gravitational pressures in each project, maximum pressure should be selected for design and implementation. Result showed that in porous pipes and in pressures of 50, 150 and 300 cm, average flow rate were 0.31, 1.4 and 4.2 liter per hour in meter, average coefficient of variation were 0.88, 0.61 and 0.83 and average distribution uniformity were 2.2, 6.2 and 1.6 percent, respectively. In the main-treatment and in each pressure sub-treatment, samples flow rate changes at different replicates is so high that coefficient of variation was more than conventional coefficient (more than 0.6) and thus classified in unacceptable emitters. In this treatment, distribution uniformity was so low that using this irrigation method at gravitational pressures range cannot be recommended. Based on statistical analysis results, it is indicated that increasing pressure in gravitational drip irrigation have maximum effect and in pot irrigation, have minimum effect on flow rate changes, and in addition, maximum distribution uniformity among samples was in gravitational drip irrigation while in porous pipe irrigation besides high coefficient of variation, minimum distribution uniformity among samples were observed.
Due to the high influence of pressure changes in gravitational pressures on hydraulic characteristics of mentioned three irrigation method, among investigated gravitational pressures in this study, pressure of 3m as appropriate pressure at gravitational pressures and among localized irrigation methods, gravitational drip irrigation were recommended. It is recommended to paying attention to the development of gravitational drip irrigation application in large-scale garden and agriculture projects with positive approach.

In order to produce the world’s growing population food demands, it would be necessary to increase the productivity. Most of this increase should be gain by funding for improving irrigation and drainage at current fields. High costs of these projects and the funds’ limitation make challenges to conduct the projects; so in order to have optimized use of the limited funds, it would be necessary to spatial prioritize the projects. At the current study spatial prioritization of subsurface drainage within the Alborz irrigation and drainage project was evaluated by using geographical information system (GIS). Prioritization was done based on the electrical conductivity and depth to water table. After determining limitations for effective factors on positioning, the interpolation done and interpolated maps were exported. After complexion of the interpolated maps for different factors, the prioritization map for conducting subsurface drainage was gained. The geostatistical analysis tool of ArcGIS software was used for interpolation. According to the results the kriging method had acceptable results for interpolation. After positioning the locations with various prioritizations, it founded that an area about 10300 ha (about 54.64 % of total area) was in the 1st and 2nd prioritizations. Generally these lands were at the northern half of area near to Caspian Sea. The main problems of these lands were salinity, swamplands or mixture of these two factors. According to the positive effect of drainage on rice productivity as one of the main crops of the area, conducting subsurface drainage systems for higher priorities is suggested.

In this study downscaling of temperature was down in Tajan Plain located in the province of Mazandaran. The result of atmospheric general circulation models was obtained with HadCM3 climate model under scenario A2. Since the output of atmospheric general circulation models has a low locative resolution, should be downscaled in the area or Basin level that it was conducted with statistical method. The statistical methods used included of downscaling SDSM5.5. And artificial neural network model. In this study, by using the average daily temperature data of Kordkheil Station during the30-year statistic Period (1971-2001) and the large-scale variables NCEP, as inputs to the neural network and SDSM model, simulation and downscaling was down respectively of the maximum and minimum temperature in the last period to determine models error. To this end were used of the features and functions available in the programming software MATLAB. Then To evaluate the performance of the models, were used the statistical criteria including of correlation coefficient, coefficient of declaration and root mean square error between observed and predicted values ​​of temperature. The obtained results show the appropriate performance of SDSM model for downscaling temperature Than the ANN model. So that the error percentage of SDSM model is lower and the correlation coefficient is more than the ANN model. The best Structure of neural network to simulate of maximum temperature is perceptron model with four hidden layer with the 5-5-6-6 architecture and for the minimum temperature Variable is perceptron model with three hidden layer with 5.3.1 architecture.

Implementation of subsurface drainage in Northern Iran paddy fields is crucial to achieve the feasibility of round-cropping and improve sustainable use of limited soil and water resources. One of the subsurface drainage systems is bi-level system that can be installed because of lower costs than conventional and better control in drains discharge. Installation of this system needs suitable knowledge of designing of subsurface drainage systems due to layered soil of paddy fields. In this study¡ an analytical solution of two dimensional transient saturated flow of Bear equation to subsurface drainage in a paddy field is presented to investigate the bi-level drainage systems operation. Also¡ due to importance of vertical head in clay and layered soils¡ a modified procedure was performed to separately involve vertical head. Validity of the solution has been evaluated by comparing with the field data collected at paddy fields of Northern Iran. The two dimensional solution was not able to reasonably predict the water table profile. But the obtained results indicated that considering the vertical resistance in the media improved the simulated data in the bi-level subsurface drainage systems and provided good representation of water table dynamics. The differences between field data and results were only 21% for modified procedure in comparison with 61% for two dimensional solution. Totally¡ it would be mentioned that in future work for designing bi-level drainage systems in paddy fields¡ the vertical head loss should be considered.

Crop models are suitable for simulation of crop yield by different scenarios of deficit irrigation and salinity. In this research, the AquaCrop model was evaluated to simulate the soybean grain yield and biomass under different levels of salinity and deficit irrigation in Gorgan County during 2011 and 2012 growing seasons. The model was calibrated by experimental data of 2011 and validated with data of 2012. The experiment included three irrigation levels of 100%, 75% and 55% water requirement and three salinity levels of 0.7, 5 and 10 dS/m. Statistical indices of the results of validated model including RMSE, E, and d for grain yield were 0.225 ton/ha, 0.88 and 0.97, respectively, and for biomass, they were 0.718 ton/ha, 0.77 and 0.95, respectively. Results showed that grain yield decreased with decrease in the amount of irrigation water and increase in salinity level. Further analysis showed that the sensitivity of AquaCrop model to the canopy decline coefficient (CDC) was more than the other parameters at senescence and maximum canopy cover stages.

Water shortage is the most important factor affecting crop production in the world. The deficit irrigation is a way to reduce water consumption in farming. The Partial Root- zone Drying (PRD) irrigation is a new improvement in deficit irrigation in which the half of the root zone is irrigated alternatively in scheduled irrigation events. In the fixed partial root zone drying (FPRD) the irrigation is fixed to one side of the root zone in the growing season. Maize is a drought sensitive crop. In maize, secondary traits related to drought resistance are considered in producing tolerate cultivars.
An experiment was conducted in order to investigate the effects of regulated deficit irrigation, variable partial root zone drying (PRD) and fixed partial root zone drying (FPRD) on the yield, physiological and photosynthetic parameters of forage maize (KSC 704) during the growing seasons of 2014 in Mashhad region. A factorial experiment based on randomized complete block design with four replications was carried out. The treatments included the full irrigation (FI) and the deficit irrigations (regulated deficit irrigation (DI) and the replacements of 80 % (DI80) and 60 % (DI60) of total water requirement, fixed PRD (FPRD) at 100% (FPRD100), 80% (FPRD80) and 60%(FPRD60) of water requirement, and variable PRD at 100% (PRD100), 80% (PRD80) and 60% (PRD60) of water requirement). Drip irrigation tapes were placed between plant rows. In the full irrigation and regulated deficit irrigation treatments, the plants were irrigated from two sides for every irrigation. In the PRD, one of two neighboring tapes was alternatively used for irrigation. In FPRD, a drip tape was used for two plant rows and irrigation was fixed to one side of the root. The irrigation interval was 3 days for all treatments. Dry and fresh forage yield, leaf area index (LAI), stomatal conductance, leaf relative water content (RWC) and chlorophyll content were measured.
All the measured traits were affected by the deficit irrigation. The highest fresh forage yield (72099 kg/ha) was produced by the full irrigation treatment. The statistical comparison showed that there was no significant difference between regulated deficit irrigation and PRD method for the fresh forage yield. But the FPRD treatment reduced the fresh forage yield. There was no significant difference between the fresh forage yield of FI and PRD80 treatments. The dry forage yield was affected by the different irrigation methods, irrigation levels and the interaction effects of the treatments All the measured traits were affected by the deficit irrigation. The highest fresh forage yield (72099 kg/ha) was produced by the full irrigation treatment. The statistical comparison showed that there was no significant difference between regulated deficit irrigation and PRD method for the fresh forage yield. But the FPRD treatment reduced the fresh forage yield. There was no significant difference between the fresh forage yield of FI and PRD80 treatments. The dry forage yield was affected by the different irrigation methods, irrigation levels and the interaction effects of the treatments (p According to the results, it seems that the negative effects of water stress on physiological and photosynthetic parameters in the early growing season is not significant and increases with the aging of the plants. Water stress decreases the absorption of carbon dioxide and the photosynthesis by reduction in the stomatal conductance. As well as, reducing the leaf area decreased photosynthetic area and the production of asymylats in the water stress conditions and ultimately reduced the forage yield significantly. The PRD method increased irrigation water productivity. With respect to this fact that no difference between the dry matter yield, LAI, chlorophyll content and RWC in the FI, PRD100 and PRD80 treatments was observed, it seems that applying Partial Root- zone Drying (PRD) method will result in lower water consumption during forage maize production at Mashhad environmental conditions.

The salinity of water and soil is called white death in many countries, because of its importance. Generally, the quantity of leaching water, energy consumption and time usage of soil remediation procedure are important factors which affect suitable method of soil reclamation. Electrokinetic (EK) is a physical method for salt extraction such as chemical, Organic and inorganic compounds. In this study, the horizontal placement of electrodes along with leaching procedure was used in Electrokinetic remediation of a saline-alkaline soil. For this purpose, two aluminum and reticular electrodes was placed above and under the soil column as anode and cathode, respectively. The soil columns heights were 10, 20, 30 and 45 cm. Then leaching water (30 mm) every day and totally Equivalent to Four times pore water was entered to soil and properties of drain water was measured. Although, leaching procedure without applying electrokinetic technique was done as control treatment. The results showed that Electrical Conductivity (EC) of drain water and current rate was changed sinusoidal in EK. Although, PH and temperature of drain water was changed between 6.8 to 9 and 23 to 35 centigrade, respectively. Leaching of cations increased in EK technique significantly (p

Regional development planning requires knowing of climate parameters and adaptation to climate change in future. This is especially more important for Mazandaran province which economy is mainly dependent on agricultural production. In this study, changes in minimum temperature, maximum temperature, precipitation, solar radiation and the number of hot and freezing days of Ghaemshahr city (Mazandaran province) were predicted by the year 2100 and possible effects of these changes on the agriculture of the region was discussed. The climatic variables were predicted by HADCM3 general circulation model under A1B, A2 and B1 scenarios using LARS-WG downscaling model. Evaluation of the model using statistics including model efficiency, coefficient of determination, root mean square error and mean absolute error indicated acceptable performance of the model to simulate future climate conditions in the region. Increases in monthly average of minimum and maximum temperatures in the warmer months will be more than those in the cold months. Increase in the minimum temperature was generally higher than that of the maximum temperature. The average of minimum temperature increase for all scenarios in future periods was 1.65 ° C, while it was 1.13 ° C for maximum temperature. In January, February, March, April, October and November, rainfall generally will increase compared to the base period and in the other months, it will decrease. Also, the amount of solar radiation will decline in all scenarios. On average, potential evapotranspiration will increase by 8.24, 10.47 and 12.68 % during 2011- 2100 compared with the base period under B1, A1B and A2 scenarios, respectively. Based on the results, modification in cropping calendar and pattern and improvement of irrigation and drainage practices are necessary to provide sustainable agriculture in the region under climate change.