نشریه مدیریت آب در کشاورزی
سال نهم شماره 1 (پیاپی 17، بهار و تابستان 1401)

Due to the critical conditions of Lake Urmia, improving irrigation methods as one the effective solutions is considered by the country's water managers. The present study was conducted to evaluate the effect of improving agricultural activities with the aim of reducing water consumption on greenhouse gas emissions in the provinces of East Azerbaijan (five cities) and West Azerbaijan (six cities) during the autumn and spring crop season on tomato, wheat, and sugar beet crops. The results of autumn wheat cultivation showed that the amount of CO2 produced in East and West Azerbaijan decreased by 22 and 28%, respectively, compared to the control treatment. Carbon footprint in East and West Azerbaijan in the treatment compared to the control shows a decrease of 39 and 35%, respectively. The results of spring cultivation for tomatoes showed that the amount of CO2 produced in the treatment was reduced by 25% compared to the control So that this amount decreased from 3925 in the control to 2917 kg/ha in the treatment. The carbon footprint of tomato production also showed that it was equal to 0.04 in the treatment and equal to 0.06 in the control (Kg CO2/kg) and had a decrease of about 33%. For sugar beet in West Azerbaijan province, the amount of CO2 produced and carbon footprint in the treatment decreased by 11.7% and 28.5%, respectively, compared to the control.

At present, the tariff for agricultural water in irrigation networks is calculated based on the Law on Stabilization of Crop Water approved in 1990, based on 1% to 3% of the planted crop. Since the method of calculating agricultural water tariffs is non-volume and based on two performance indicators at the level and price of the product, it does not cover the costs of operation and maintenance of irrigation network facilities. It has caused a waste of water resources. Therefore, water pricing based on economic principles and foundations is one of the most critical requirements. The purpose of this study is to obtain the optimal price of agricultural water in the irrigation networks of northern Khuzestan. To determine this price, the average cost and the marginal cost of production per cubic meter of water were calculated. The water demand function of 8 agricultural products was obtained using time series data from 2003 to 2018 using the ordinary least squares method of OLS. In Eviews software, estimation and price elasticities of water demand were obtained. Then, with the help of MATLAB software, the optimal Ramsey price of water for the above products was calculated. The results show that optimal pricing first leaves the industry with a deficit. According to the Ramsey rule for the study area, the second optimal price (Ramsey price) defines the most efficient prices according to the budget constraint to be met. Also, to achieve maximum social welfare, the price of water for corn, barley, wheat, and rose crops, which have a better-guaranteed income, is higher than the average cost of water, and the products of okra, peas, beans, potatoes, and tomatoes are less than the average cost of water.

Due to the water situation in the country and on the other hand the increase in water needs, water resources management is important. Since the major share of water consumption is allocated to the agricultural sector, water allocation is one of the issues that should be considered. In the present study, a new and at the same time high-performance method based on the Whale algorithm (WOA), for the optimal allocation of water resources of Sufi-chai irrigation and drainage network located in East Azerbaijan province in the agricultural sector during the statistical year data were used from 2005 to 2013. The whale algorithm is one of the newest meta-heuristic algorithms inspired by the bubble net hunting method performed by humpback whales. The results were compared with the results of the ICA algorithm. The objective function was determined based on each of the products and their performance and the income from each product, and then the maximization of the objective function and the optimal allocation of water resources was performed by WOA and ICA algorithms. The results showed that by increasing the application coefficient to 0.9, the profit from the optimal water allocation is associated with a 30% increase in economic profit. Meanwhile, the WOA algorithm, compared to the ICA algorithm with an allocation of 1720 MCM per year, has 8.90% of the optimal use of water resources in agriculture. In general, the use of intelligent evolutionary methods can be a good solution for optimal water allocation in the agricultural sector.

The water crisis is one of the major environmental challenges. Due to the problem of cheaper and faster desalination of seawater than seawater, in order to supply water, it has become increasingly important. Desalination using biological methods involves the use of different species of plants, microorganisms, algae or a combination of them, which can be effective in reducing water salinity. The aim of this study was to investigate the desalination of saline waters using seaweed. The present study was conducted to investigate the desalination of brine waters using seaweed. The present study was performed as a factorial study in a completely randomized design. The two-way ANOVA analysis of variance was performed with two main treatments including two types of algae (Dunaliella salina and Cholorella vulgaris) and two sub-treatments including 2 salinity levels (50 and 70 milliseconds per centimeter). The experiment was performed under controlled laboratory conditions and during the incubation period, electrical conductivity was measured daily. The results showed that the uptake of chlorine, sodium and bicarbonate was significantly different in Dunaliella salina and Cholorella vulgaris algae. Decreased by 3 mmHg Based on the research results, it seems that the reduction of salt absorption in algae using salt is in algal metabolism and their growth and reproduction.

It is necessary to study of water productivity of pomegranate orchards because of limited water resources, need to improve water productivity and the importance of pomegranate fruit. In this study, the volume of applied water and pomegranate yield in more than 120 selected orchards in the provinces of Isfahan, Khorasan Razavi, Markazi, Semnan, Yazd and Fars were measured. Analysis of variance was used to investigate the possible differences in yield, applied water and water productivity. Results showed that except for yield, the difference in the applied water and water productivity was significant. The average yield of pomegranate was 21.5 ton/ha. The average volume of applied irrigation water was 14792 m3/ha. The average productivity of applied irrigation water was 1.69 kg/m3. The average water + effective long-term rainfall productivity was 1.47 kg/m3. The productivity of water + effective rainfall of the current year was 1.43 kg/m3. The volume of applied water in pomegranate orchards and the gross water requirement was not similar in the selected provinces. In some provinces such as Fars, Khorasan Razavi, Semnan and Markazi, the volume of applied water was less than the gross water requirement and in Isfahan and Yazd provinces was more than the gross water requirement. But on average, the volume of applied irrigation water was close to the gross water requirement in the year of the research and to the long-term gross water requirement. The average volume of applied water in drip and surface irrigation systems was 9981 and 15765 m3/ha, respectively, the percentage of reduction of applied water in drip irrigation system compared to surface irrigation was 37%.

Wheat is a strategic crop in Iran . As a result, various policies and plans have been developed and or implemented in Iran. In macro-level documents, attention to this crop as a strategic crop is still low. However, in the policies and executive plans within the system of those in charge of crop production , it is one of the main challenges and concerns and various policies and plan have been developed and implemented. Such as policies and plan to use more modern irrigation methods , more use of conservation agriculture, “mutation plan” of crop production in rainfed agriculture, various research-development plans with international research institutes, agro-technics and breeding programs, implementation of the plan to increase wheat self-reliance, increase, the productivity of cereals-based production systems, increase the yield and water productivity of wheat in wheat systems, and formulate policies and implement instructions related to encouraging the nominated farmers with high water productivity. Of the highlights of these policies and plans is the special attention to improving the production of rainfed crops and more involvement of the private sector and relevant institutions in improving the production and productivity of this crop. However, the results of this study show that the developed policies and plans have not been well documented, developed, and or codified, and are mostly in the form of official statements in the media or case reports and circulars. Moreover, reviewing the progress and monitoring of these policies and plans in regard to identify obstacles to their implementation, as well as their cross-sectional and sustainability in terms of work continuation, are some of the weaknesses and shortcomings of such policies and plans. In conclusion, recommendations and solutions of various categories including planning-policies and strategies to improve the yield and water productivity of wheat in the country are presented.

With the increasing population, increasing production in rainfed fields is necessary for food security. With regard poor distribution of rainfall in recent years, Water management for rainfed fields in critical conditions has priority. The results showed that for one or two irrigation in sensitive times, the yield of rainfed fields increased. Although supplementary irrigation in order to improve yield and water use efficiency in rainfed fields is the attention the study of special characteristic rainfed fields such as topography, slope, and the access to water resources is essential. The main purpose of this study is to evaluate the ability of supplemental irrigation in rainfed fields is based on the topography and slope. According to the land use map of Qazvin province, about 284 thousand hectares are irrigated lands and 132 thousand hectares are rainfed fields in the province that most of these lands in the Qazvin plain. Then with regard to the slope map from the region, rainfed fields for doing supplementary irrigation are classified into 4 classes: 0-5%, 5-8%, 8-12%, and more than 12%. The two land use and slope maps of Qazvin province were unified. In rainfed fields, 83, 10.7, 3.8, and 2.5% of fields have slope 0-5, 5-8, 8-12, and more than 12%, respectively. So 97.5% of rainfed fields have the ability to do supplementary irrigation. Most of these lands are in the Qazvin plain and in the vicinity of irrigated lands.

The purpose of this study is to assess the impact of different dimensions of service quality on customer satisfaction of the company operating the irrigation networks in the northern region of Khuzestan.The geographical territory of the company is one hundred and ninety thousand hectares in the north of Khuzestan, where a variety of horticultural and agricultural products such as wheat, fodder, vegetables and summer crops are grown.This research is based on the service quality gap model (SERVQUAL) and in addition to ranking the components of this model, the gap between customers' expectations and perceptions of the quality of the company's performance has been analyzed. This research is applied in terms of purpose and based on the method of data collection is a descriptive survey. Eighteen thousand farmers are working in the north of Khuzestan and the statistical population of this study is the heads of these farmers with a number of six thousand people who have a contract to buy water with the company. The sample size based on the Cochran formula was determined to be 361 people. In practice, 375 questionnaires were collected. The data collection tool is a questionnaire that has been localized according to the company's activities and the type of customers. Structural equations were used to evaluate the model and correlated t-test was used to significantly measure the difference between customers' expectations and perceptions. Findings indicate that Pearson correlation coefficient between customer satisfaction with the dimension of physical factors is 0.49, reliability 0.46, responsibility 0.65, guarantee 0.53 and empathy 0.42. Therefore, all the studied dimensions are effective on the customer satisfaction of the operating company. The correlation between service quality and farmers' satisfaction is 0.58

Due to the limited water resources and recent droughts, as well as the adverse environmental effects resulting from the unprincipled release of agricultural drainage waters, the management and optimal utilization of agricultural drainage waters is essential. In this study, the possibility of reusing drainage water from sugarcane cultivation in Khuzestan plain for barley and eucalyptus cultivation and final discharge to artificial wetlands or evaporation ponds was investigated as a simulation program. In this regard, using desalination tests, the best empirical model of soil desalination was determined in the study area. Using an empirical desalination model, a simulation model was prepared to determine the final values of salinity of soil (ECf) for applying the depth percolation from irrigation of sugarcane. Then, based on the amount of sugarcane drainage water and water requirement of barley and eucalyptus, the area of arable land of these plants was determined. Also, by preparing a calculation program, the area of evaporative ponds or artificial wetlands was determined to drain the remaining drainage water from all crops. The results showed that using the drainage water of one hectare of sugarcane in the second year of cultivation, 0.5 hectares of barley can be cultivated and using the remaining drainage water of one hectare of sugarcane and drainage water of 0.5 hectare of barley, 0.22 hectare of eucalyptus planting. Finally, the area of drainage areas to create one hectare of evaporation pond (zero water balance), wetland (water level + 0.25 m) and wetland (water level height + 0.5 m), using the remaining drainage water amounts of sugarcane, barley and eucalyptus equal to 0.4348 m during a crop year was obtained equal to 5.715, 12.61 and 19.51 ha, respectively.

In order to investigate the effect of combining irrigation methods and nitrogen fertilizer levels in single and multiple seedling cultivation system on yield and water productivity of Tarom Roshan rice (Oryza sativa L.) cultivar, an experiment was conducted as split split plots based on randomized complete blocks with six irrigation treatments. The irrigation treatments include permanent flood irrigation method during the growing season (T1, control), strip drip irrigation method after the refilling of missing hills stage (T2), tillering (T3), clustering (T4), flowering (T5) and pasting (T6) with 50% of the amount of permanent flood irrigation water for each irrigation treatments. Two treatments of 90 (N1) and 180 (N2) kg/ha nitrogen fertilizer from urea source and two treatments of single (S1) and multiple (S2) seedlings was applied in three replications in 2019 in the rice research farm of Guilan University. The results showed that the highest grain yield with 6730.7 kg/ha was obtained in the treatment of T5 irrigation method with single seedling system and there was no significant difference with the treatments of T3 irrigation method with single planting and T1 with multi-seedlings systems. Additionally, the highest water productivity based on grain yield with 0.844 kg/m3 was obtained in the treatment of T2 irrigation method with multi-seedling system and there was no significant difference with the treatments of T2 and T3 irrigation methods with single seedling system. Also, the highest water productivity based on grain yield in all irrigation treatments was associated with N2 fertilizer treatment. Therefore, for higher grain yield with higher water productivity, N2 fertilizer level can be applied and in water restriction conditions, T3 irrigation method with S1 cultivation system can be applied in Rasht region.

Due to successive droughts and as a result of quantitative and qualitative reduction of water resources in Fars province, changing the cultivation pattern from High-water crops to low-water crops and the development of rain fed orchards has become inevitable. As in many cities of the province such as Fasa, Jahrom, Khafr and Kharameh, cultivation of green fig trees in addition to Estahban city is developing. This study was conducted to investigate the effect of supplementary irrigation on reproductive characteristics of fig crop in Kharameh city during the years 2016-2017 and 2017-2018 by using completely randomize block with 4 treatments of irrigation method and in 5 replications. The treatments included the1500 liter supplemental irrigation in March, May, August by flooding method (T1), subsurface drip irrigation method (T2), microjet irrigation method (T3) and control treatment (no supplemental irrigation) (T4). The results showed that the number of bright yellow fruits increased by 247% in the micro jet treatment compared to the control. The number of AA grade and hundred -one fruits, which are the best quality fruits in figs, were significantly higher in micro jet irrigation method than other irrigation methods. Also, The weight of bright yellow and AA fruits was highest in micro jet irrigated trees and the difference with other treatments and control treatment was significant. The physical productivity index of water in flood and micro jet treatments in the initial year of the project was 0.11 kg / m3, which was the highest value among the treatments.

The rapid spread of the coronavirus and its high mortality rate has caused serious and widespread damage to society and the economy. Therefore, the present study examines the correlation between Covid-19, water security, food security, and the environment. The Covid-19 outbreak has prompted an expansion in the utilization of water in the country. during the pandemic of coronavirus, some arid parts of the country, which have poor water security in terms of water poverty and environmental water supply, or sometimes face water insecurity, have become more unsafe in terms of water. the Covid-19 outbreak and implementation of the National Coronavirus Headquarters approvals have had many positive impacts on the environment including decreasing air pollution in the metropolitan, reducing greenhouse gas emissions, and reducing environmental pollution (such as rivers, forests, plains, and mountains). On the other hand, it is necessary to mention that staying at home has led to producing more waste, which can be dangerous for the environment if it is not recycled; Besides, the Covid-19 pandemic has damaged the economic activities and livelihood of the people and disturbed job and food security (based on the National Document on Nutrition and Food Security (2012-2020)). The coronavirus has shown many tenets to human society, including improving personal hygiene, using masks to reduce the spread of infectious diseases and social participation. Using social participation to advance goals and resolve existing crises such as global warming and water crises can be exploited.