نشریه آب و توسعه پایدار
سال هشتم شماره 3 (پیاپی 21، پاییز 1400)

The utilization of water resources models enables correct and sustainable planning in water resources management. The purpose of this study is to optimize the use of water resources in the catchment area of Varamin plain for 10 years under different management scenarios. To achieve optimal conditions in the volume of water resources, the minimization of non-supply needs and the needs of different land use in Varamin plain were studied. Accordingly, the situation of water resources in Varamin plain in three sectors of agriculture, industry, and drinking using WEAP model under two scenarios: a- reference with prioritization of the ministry of energy and b- scenario of reducing inlet volume by changing prioritization in the period 2016-2026  Solar was evaluated. The climate of the region was studied based on the model of the blue year (flow, precipitation, evapotranspiration, temperature) and entered the model. The results showed that according to Scenario A, we will have a 30% shortage of drinking water supply in the region, and this is 37% for the scenario of the reduced input volume. Based on the results, the reference scenario, which in terms of meeting different needs and reliability index of water needs and maximum volume of water not provided during the statistical period, compared to the scenario of the reduced input volume, has a better performance for the Varamin plain, It was considered as the preferred scenario.

In South Khorasan province, water shortage is one of the main limiting factors for the development of economic activities in the coming decades. In this province, similar to other parts of the country, the optimal use of water in the form of culture has not yet found its special place, so achieving a relative equilibrium in the supply and demand of water is a basic and essential principle. This is not possible except by creating a comprehensive system in water management and consequently water security. to prevent crises caused by water insecurity, it is necessary to identify rapid developments and defective trends in current water management based on the climate, social, economic, and other realities in each region. In this regard, the current state of water resources in this province was monitored and evaluated by creating a set of indicators. Then, with the help of gray analysis, which is a kind of hierarchical ranking method, the plains of the province were ranked in terms of water security.  The results of the gray analysis also showed that the highest score of water security level is in the Deh-e-Salm plain (0.524), Dehno_mighan plain (0.519), and chahak-Mousavieh plain (0.504). Their degree of Security is mainly interpreted by their ability to reduce the risks of water shortage and water scarcity, although it will never be secure to study unless there is a risk of water shortage and water scarcity. There are important study areas such as Birjand Plain (0.462) that are currently in water insecurity. The highest levels of Water insecurity are observed in the South Khorasan Province, Sarayan (0.268) and Boshrouyeh (0.363).

Today, the issue of water shortage has become a major challenge in Iran. Since the agricultural sector has a high share in water consumption in order to increase population and food supply, so the study of water footprint that indicates the volume of water that directly or indirectly to produce goods or provide any services Consumed has significant potential to help water management in agriculture. In this study, water footprint in cucumber production from 1394 to 1398 using AGWAT software in 4 areas of Darhshahr city, Ilam province, which have the highest area under cultivation and export of cucumber is investigated it placed. The results showed that in Faryab lands of the four studied parts, Ermo rural district, Abbas Abad rural district, Chamjab village and Darhshahr center, the share of green, blue, gray and white water footprints were 16%, 20%, 20%, 25%, respectively. Percentage of total water footprint in cucumber production in Darhshahr city. In the study, the average total water footprint in Faryab lands is about 9,684 cubic meters per ton. Therefore, according to the trend of water footprint in the study areas, the replacement of new irrigation methods, including; Drip irrigation with low wastage and higher efficiency is recommended instead of flood irrigation in cucumber cultivation in these areas.

Requiring accurate, complete and reliable data is the first step in climate studies. Incomplete data challenges climate analysis. Missing (incomplete) data is often found in meteorology. Therefore, completing the data (imputation) is the primary need for analysis. There are several ways to imputation missing data that vary depending on the data type and climatic characteristics of each region. Precipitation and temperature are the most important variables of meteorology and climatology. The length of the statistical period plays a pivotal role in the accurate analysis of these variables. The monthly temperature of three cities in Iran, including Mashhad, Bushehr and Jask, has been available in a book called World Weather Records since about 1890. This information contains missing data, especially during World War II (1941-1949). This missing data is more visible.  The purpose of this study is to increase the accuracy of estimating these missing data by introducing the applied MICE method and providing a complete series of monthly temperatures over 130 years. Stations from neighboring countries were selected as independent (predictor) stations in the patterns. First, the missing monthly temperature data of these three stations were estimated by fitting regression patterns (RMSE of 0.71 to 0.94 οC). The classical regression method requires the study of basic hypotheses and pattern pathology. These patterns were also estimated by the MICE method (RMSE of 0.39 to 0.82 οC). The results of the study and implementation of this package in Rstudio show the superiority of this method. This method is designed for missing data, does not have regression problems, and has many capabilities. Therefore, it is recommended to estimate missing meteorological data.

In recent years, the outflows from the Karun Basin, especially in the interior of Khuzestan province, have decreased significantly. This study aimed to investigate the effect of climatic factors and drought on the inflow and outflow of the Karun basin in two parts (basin area inside Khuzestan plain and basin area outside Khuzestan plain).  The results indicate the onset of adverse climate change during the last two decades. During this period, especially in the last ten years, the study has witnessed a large decrease in rainfall compared to the previous decade in the Karun Basin. Changes in average, minimum, and maximum temperatures, evaporation and drought have also increased during the last two decades. Also, the results related to the effect of climatic parameters on the output discharge of the Karun basin showed that in Khuzestan province 83% of the output discharge changes were affected by climatic parameters (including rainfall, drought, and maximum temperature, respectively) and outside Khuzestan, 82% of discharge changes are due to climatic parameters (including rainfall, maximum temperature, and drought, respectively). Meanwhile, the surface currents of the basin during the last decade have been more critical than other decades and the output discharge outside Khuzestan (input to the province) has decreased by about 27%, and inside the province and the output of the basin has decreased by 44%, which due to the almost identical effect of climate on both areas, these changes can be attributed to the existence of other factors, including land management and human factors.

Considering that wheat fields are mainly irrigated by surface (basin) and localized (drip) methods, this study aimed to investigate, compare and analyze the effects of total applied water and yield factors on wheat Water Use Efficiency (WUE) of each irrigation system in Yazd province. In this way, the priority of addressing each of these factors in the two irrigation systems can be determined. The results showed that in the surface irrigation method, reducing the volume of applied water has played a more important role in improving the WUE than increasing the yield. In other words, to increase the wheat WUE of surface methods, implementation of water use optimization solutions are more prioritized compared to crop yield enhancement practices. In contrast, in the case of the drip irrigation method, the crop yield enhancement solutions have played a more decisive role in improving wheat WUE. In these fields, wheat agronomic practices such as proper planting date and density, selecting suitable and high yielding varieties, proper irrigation cycle, proper fertilizer application, and pest and disease control have had a significant role in WUE of wheat, which requires high attention by the farmers to these issues. It was also observed that despite the possible reduction of applied water in drip irrigation compared to the surface method and consequent quantitative enhancement of WUE, but there may be the possibility of low and unacceptable wheat performance. This can cause economic inefficiency of the drip irrigation system for wheat. So, it is highly recommended to consider and implement the above-mentioned agronomic practices in wheat drip irrigated fields.

Nowadays, due to the decrease in fossil fuel resources, generating biogas from corruptible waste is getting attention. Anaerobic digesters are utilized in wastes management and produce renewable energy from it. Generally, the anaerobic digesters convert wastes to methane and carbon dioxide. Effective parameters on the anaerobic digestion process are reactor configuration, temperature range, mixing system, and waste type. In this paper, using of produced sludge in an anaerobic digester was investigated for municipal WWTP with SBR and MLE processes. For this means, Alteimour and Kheine-Arab wastewater treatment plants (WWTPs) have been considered as case studies. The applied processes in Kheine-Arab and Alteimour WWTPs are SBR and MLE, respectively. Results comparison shows that the produced sludge from the SBR process (Kheine-Arab WWTP) has no suitable potential for biogas production. However, there is potential for biogas production at the Alteimour treatment plant, and investment can be made in the future on Alteimour WWTP.

In the past, the purpose of water treatment was to reduce suspended solids and eliminate living pathogens in water, which was achieved by conventional filtration and disinfection methods. But at present, with the increase of pollution in water sources, the existing methods are not fully capable of proper water treatment. Studies have shown that disinfecting drinking water can increase the growth of antibiotic-resistant bacteria in aqueous media. Water treatment may increase the antibiotic resistance of surviving bacteria, and water distribution systems may serve as an important reservoir for expanding antibiotic resistance to opportunistic pathogens. Drinking water treatment processes cannot completely eliminate ARGs from drinking water sources, and therefore, drinking water supply systems may be an initial route of release of ARGs from the environment to the host, posing potential risks to human health. It has also been shown that the number of some bacteria increases with the amount of chlorine in drinking water and the water treatment process is not able to completely remove antibiotics from drinking water. For this reason, it is necessary to learn more about the amount and frequency of bacteria with antibiotic-resistant mutations. In this article, a brief review of studies on drinking water treatment as well as the introduction of antibiotics used in daily life through sewage and effluents and its impact on human health has been done.

Given that many commercial aquatic species of the country are bred in recirculating aquaculture systems (RASes), it is necessary to carefully evaluate and control the amount of water quality in these systems. Due to this issue, in the present study, the efficiency of membrane filtration in water treatment of RASes was investigated. First, general information about the membrane filtration process, including its types and benefits, was presented, and then, the importance of membrane filtration in removing contaminants and water treatment from aquaculture systems was discussed. Membrane filtration covers a wide range of filtration processes including reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF), and microfiltration (MF). Examination of the obtained sources showed that the membrane filtration has several advantages, the most important of which are the reduction of overall production costs, high flexibility, and high product quality. The solids in the aquaculture system come from uneaten food and feces produced by fish. These substances can cause the spread of microbial and pathogenic agents in aquatic environments. Application of different membrane filtration methods showed that these methods have significant efficiency in removing fine particles and organic matter from aquaculture effluents. Therefore, they can be used for sustainable management of water resources as well as water treatment in this sector.

Recently, the influx of dyes into water resources has disrupted the natural order of ecologists due to their toxicity to biodiversity. In this study, activated carbon prepared from rice straw was synthesized with potassium hydroxide solution in ratios of 1: 3 and 1: 2 at temperatures of 800 °C and 900 °C, and it was used to absorb reactive yellow 145 dye prepared in a laboratory that has similar properties to the real effluent of Tehran textile industry. Then, the effect of important variables on the adsorption process such as pH (2-8), contact time (15-120 minutes), adsorbent dose (30-60 mg), dye concentration (50-200 mg/L), and temperature (15-45 °C) Checked out. The results showed that the adsorption rate was inversely related to the pH of the solution and the initial dye concentration and was directly related to the adsorbent dose, temperature, and activator saturation ratio. Among the isothermal models, the Redlich-Peterson model (R2 = 0.995) with the equilibrium adsorption capacity of 324.6 mg/g had a better agreement with the experimental adsorption results and the kinetic studies showed that the adsorption process follows the pseudo-second-order model (R2= 0.995). Thermodynamic studies also showed that the adsorption process is spontaneous and the negative slope of the Van-Hoff curve indicates that the reaction is endothermic. Due to the equilibrium time of 60 minutes in the adsorption mechanism, the synthesized adsorbent has a high rate of adsorption of reactive yellow 145 dye. The synthesized adsorbent with properties such as high specific surface area, environmentally friendly, availability of precursors, and suitable performance in dye adsorption can be used effectively in dye effluent treatment systems.