فصلنامه علوم و مهندسی آبیاری
سال چهل و هفتم شماره 3 (پاییز 1403)

Flow control and regulation of water levels in irrigation canals are critical to improving the distribution network's performance, water transfer, and ease of operation of the intakes. Therefore, the network needs to improve the existing control and regulation structures and construct the new structures (Monem and Hosseinzadeh, 2012). Today, various spillways and gates have been used as control and regulation structures in water transmission networks. Elliptical LOPAC gates are a particular type of gate that researchers have considered in recent decades due to their convenient advantages (Pilbala et al., 2021). Studies have been limited so far, so in this study, the hydraulic performance of this type of gate with the presence of gradual inlet transition has been investigated both experimentally and numerically. Research on Lopac gates indicates that studies have been performed on hydraulics, mainly in a sudden contraction or full-width gates in the laboratory flume. However, in many cases, the width of the gate needs to be less than the width of the channel, and an inlet transition is necessary to reduce the energy loss. Therefore, a parabolic transition was used in this study, and in particular, the effect of the parabolic transition upstream of the elliptical Lopac gate on the hydraulic conditions was investigated using Flow-3D software.

The key to social and economic development is water, an essential natural resource. Worldwide, many areas are experiencing water supply and demand mismatches or are under extreme stress due to water shortages. Water resources have been mismanaged or limited due to an increase in demand and limitations in available water supply (Banadkooki et al., 2019). Rainfall and runoff are considered to be the main components of the hydrological cycle. In order to capture the dynamic relationship between rainfall and runoff, engineers need to develop an accurate model (Tikhamarine et al., 2022). Rainfall-runoff modeling is one of the methods of estimating runoff and a suitable tool for studying hydrological processes, evaluating water resources and watershed management (Abrahart and See, 2000). But the complexity and non-linear nature of the rainfall-runoff process and the unknown effect of the factors on each other and finally on the outflow of the basin make modeling more difficult (Moriasi et al., 2007). Therefore, it is necessary to use methods that, in addition to dynamism, have the ability to develop, have a conceptual and user-friendly structure (Shi et al., 2012). The role and importance of the mentioned process in water resources studies has caused this process to be noticed by experts (Guven, 2009). Therefore, several methods such as artificial neural networks, fuzzy and neuro-fuzzy systems, wavelet analysis, genetic algorithm, genetic programming and stochastic differential equations have been developed to model the rainfall-runoff process (Yaseen et al., 2016; Zhang et al., 2019). The development of rainfall-runoff models using different AI models has been conducted several times in the past two decades, but these models still have several shortcomings. These drawbacks are usually related to overfitting, difficulty in initializing the internal parameters related to these models and proposing the proper input-output architecture of the model (Ahmed et al., 2019).

Moghaddasi et al. (2010a,b) did a research on optimization of water allocation and distribution in irrigation network of Zayandeh Rud catchment by the use of non-linear methods of collective intelligence and genetic algorithm. In the above mentioned study, optimization has done by 4 sub-models of water distribution optimization during crop growth periods, water allocation optimization among network crops, water distribution optimization among different networks, and annual optimization of agricultural water proportion of Zayandeh Rud. Comparing the results, it can be assumed that nonlinear programming )NLP) and consequently particle swarm optimization )PSO) methods have priority to the others.in addition the study confirmed that the optimization method associates 36% more income. Management of irrigation water resources in the agricultural sector, as the most important renewable but limited resource, has been the most important challenge of the current century and has resulted in major concerns around the world. The aim of this study was to allocation irrigation water and cropping area under uncertainty with emphasis on water use efficiency (WUE) and relative irrigation supply (RIS) indices and the results were compared to the actual management in  Marun Irrigation Network.

The purpose of this study was to comparison of the of phosphorus and potassium availability in the soil and their uptake by sugarcane under subsurface drip irrigation and furrow irrigation conditions. This research was conducted in two sugarcane fields (subsurface drip irrigation and furrow irrigation) located in Hakim Farabi Agro-Industry. In this study, soil and plant sampling was done at two and four months after cultivation and the concentration of available phosphorus and potassium in the soil, shoot dry weight and the concentration of phosphorus and potassium in the sugarcane shoot were measured at two and four months. Also, the phosphorus and potassium uptake tiin sugarcane shoot were calculated. Statistical analysis and average data comparison was done by t test. The results showed that at two months after cultivation, under subsurface drip irrigaon condition, the phosphorus available concentration in the soil, the concentration and uptake of phosphorus (19.2%) and potassium (22.9%) in the sugarcane shoot were significantly more than the condition of furrow irrigation. Also, at four months after cultivation, under the subsurface drip irrigation condition, the available concentration of phosphorus and potassium in the soil and phosphorus (13.9%) and potassium (14.8%) uptake in shoot were significantly more than the furrow irrigation condition. Therefore, it can be concluded that in the early stages of plant growth (two and four months after cultivation), the phosphorus and potassium availability in the soil and their uptake by sugarcane plant can be improved under subsurface drip irrigation conditions.

Water shortage is one of the most important threats to the survival and development of agriculture in the country, so it is necessary to use different methods of farm water management to improve the water productivity and water efficiency. In order to investigate the effect of vermicompost and biochar on the yield and water productivity of corn, a factorial research was conducted in Khorramabad city with a completely random basic design in three replications, the first factor was irrigation water treatment at 4 levels including irrigation based on supplying 100% of Water requirements (I1), providing 80% of Water requirements (I2), providing 60% of Water requirements (I3), providing 40% of Water requirements (I4) and the second factor including organic fertilizer, vermicompost (C), biochar (B) and control treatment (I). The results of the research showed that maximum wet yield, dry yield and plant height were observed in the I1-C treatment, which were 126.71 tons per hectare, 46.27 tons per hectare and 2.35 meters, respectively, and the maximum amount of wet productivity and dry productivity was obtained in I2-C treatment was 16.79 kg/m3 and 5.9 kg/m3, respectively. Although the use of vermicompost had better results than biochar, the use of biochar also increased the yield compared to the control treatment, so that in the treatment without water stress and using biochar, the dry yield was 27.06%, the wet yield was 29.78%, and the biological productivity 36.41% and more productive 46.01% increase in control treatment ratio was observed. Therefore, the use of these two organic fertilizers was significantly effective in increasing the yield and water productivity of corn.

The study of supply and shortage related to rice also has a similar trend with other products in this sector, out of the total 17 million cubic meters of water demand, 7 million cubic meters have been supplied and 42% of it has not been supplied. Of course, checking the numbers of supply and shortage in different months of this product shows that the shortage is mainly in the hot months of the year when the base flow and release of the reservoir in this region is reduced and it is between the months of May to September and according to Due to the priority of less supply compared to the other two products on the one hand and the relatively lower demand of this product with black root and citrus fruits, its supply has had such a trend. In the case of wheat, grain corn, and oilseeds, there is a more or less different trend, so that the availability of oilseeds was almost 50%. The results of the balance of resources and water consumption in the Tajan catchment basin in the existing conditions by the VENSIM model during the years 2013-2017 showed that the agricultural demand in Finesk, Shahid Rajaee, Zarem and the Tajan diversion dam was 18, 146, 93 and It is 478 million cubic meters, respectively, 6 million cubic meters (33%), 93 million cubic meters (63%), 100 million cubic meters (59%) and 380 million cubic meters (80%) have been supplied, which is only in the Band area.

Rivers are one of the most important water sources that play an important role in supplying water for various needs including agriculture, industry and drinking. Determining the flow regime and water quality of the river is an important factor in determining the health of the river. In this research, in order to determine the water quality and zoning of Karoon River (Bavi region) using IRWQISC, NSFWQI quality index and Liu index, monthly water sampling was done from April to March 1402. Three indicators and their presentation in the form of zoning maps, the comprehensive system of water quality assessment and management can be used by managers and decision makers to achieve better health and sustainability of water resources. According to the results of the IRWQISC index, the quality of the river is in the medium to relatively good category, while according to the NSFWQI index, the river water is in the poor to medium quality category, and according to the Liu index, it is in the relatively polluted category. It seems that NSFWQI index and Liu index are more strict, but there can be suitable indices to use and evaluate water quality for different purposes. Considering the water quality from the upstream stations to the downstream side of the studied area, the impact of industrial activities, agricultural drains and urban areas should not be ignored and water quality monitoring in this area.

Due to the limited water resources and the need for optimal use of them, the importance of using treated wastewater in cases where lower water quality is required is determined.( Munoz and Guieysse, 2006) On the other hand, untreated wastewater can lead to many environmental issues.( Kalyuzhngi et al,2005)  The use of low-tech wastewater treatment systems and no energy consumption or low energy consumption help to reduce economic costs and improve the environment. Since biological processes are one of the most common and affordable methods in wastewater treatment and the main purpose of biological treatment is to use microorganisms to convert organic matter into other products, remove or reduce nutrients and other contaminants, so the purpose of this study is to reduce TSS, total nitrogen and nitrate using the combined process of AO in the treatment of industrial wastewater from metal industries.( Zhou and Lisng, 2008; Adam et al 2006).