Showing 411 results for Water
S. Koohi, B. Bahmanabadi, Z. Partovi, F. Safari, M. Khajevand Sas, H. Ramezani Etedali, B. Ghiasi,
Volume 27, Issue 4 (12-2023)
Abstract
Water supply remains a significant challenge in arid and semi-arid regions, and in addressing this concern, unconventional water sources have gained prominence. Notably, the extraction of water from air humidity, classified as an unconventional water source has seen increased adoption. Diverse techniques have been developed to achieve this goal, with the utilization of mesh networks being particularly prevalent. Consequently, this study assesses the evaluation of the performance of the ERA5 dataset in the simulation of atmospheric variables that influence the ability to assess water harvesting from air humidity (including temperature, wind speed, and water vapor pressure). Also, the possibility of water harvesting from air humidity was investigated in Qazvin Province. The outcomes demonstrated the benefit of incorporating adjustment coefficients in estimating temperature and wind speed using the ERA5 dataset. Based on these findings, the northwestern and southern regions of the province (Kuhin and Takestan) exhibit notable potential during spring and summer for water harvesting from the atmosphere. The peak water harvesting for these stations in the summer is estimated at 10.2 and 9.7 l/day.m2, respectively. Using the ERA5 reanalysis dataset, the annual average potential for water harvesting in the stations was evaluated at 7.9 and 4.6 l/day.m2, respectively. Notably, the minimum water harvesting capacity during the summer season recorded in Qazvin is equal to 3.39 l/day.m2, which can be planned for use in irrigation requirements of green spaces, fields, or gardens.
M. Baki, J. Abedi Koupai,
Volume 28, Issue 1 (5-2024)
Abstract
The improvement of water consumption efficiency is very significant, especially in arid and semi-arid regions. In this research, the effects of three hydrogel rates (0, 10, and 50 Mg ha-1) and three irrigation regimes (50%, 70%, and 100% of water requirement) on growth, yield, and oil production of Thymus daenensis were studied in a lysimetric experiment. The process of hydrogel synthesis was performed with sodium alginate as the main bone of the polymer and acrylic acid and acrylamide as monomers with the rapeseed meal biochar was made at 300 ºC. The results showed that the essential oil content produced by the plant was impressed by the hydrogel application. The essential oil content increased with an increase in water deficit, but the essential oil yield decreased in the lysimeters with water deficit compared to the ones without water stress. Besides, the application of 50 Mg ha-1 hydrogel caused a 17% increase in the dry matter and a 12% increase in the plant's height. According to the results of this experiment, the application of hydrogel caused the improvement in most characteristics of the Thymus daenensis in water stress conditions.
F. Gholamzadeh, H. Asgarzadeh, H. Khodaverdiloo, M.r. Mosaddeghi,
Volume 28, Issue 1 (5-2024)
Abstract
This study was conducted in the summer of 2021 to evaluate and validate the gravimetric soil water content measurements using a field oven. Ten soil types with a salinity of saturated paste (ECe) less than 4 dS m-1 and three saline soils were studied around Urmia Lake. Plots with dimensions of 1 m × 2 m were prepared for the selected soils to measure gravimetric soil water content and soil physical and chemical properties. The gravimetric water content (θm) values measured using the field oven (i.e., θmFO), were compared with those measured by a standard lab oven (i.e., θmLO). The soil water content values measured in the lab, regarded as a benchmark, were measured at 105 °C for 24 h. Temperatures of 120, 140, and 160 °C with three durations of 10, 15, and 20 min were used to dry the soil samples in the field oven. There was very good compatibility between the values of θmFO and θmLO when the soil samples were dried in the field oven for 15 or 20 min at all three temperatures. Significant linear relations were obtained between the θmFO and θmLO values as the slopes of linear relations were close to 1, the intercepts of relations were negligible and the distributions of measured data around the line 1 to 1 were unbiased. The minimal effects of soil organic matter content, clay content, salinity, and bulk density on water content measurements by the field oven indicate an important advantage of this method. These results confirm the high efficiency of the field oven for fast and reliable measurements of water content in different soils.
A. Zare Garizi, K. Shahedi, A. Matboo,
Volume 28, Issue 1 (5-2024)
Abstract
Water quality characteristics play a crucial role in water resources management, watershed health assessment, and implementing effective management strategies. The objective of this research was to present an overall assessment of the surface water quality in the Gorganrood River Basin to be utilized for developing effective watershed management plans and programs. Various physicochemical water quality data including main anions and cations, Total Dissolved Solids (TDS), Electrical Conductivity (EC), Sodium Absorption Ratio (SAR), pH, and total hardness recorded at 25 hydrometric stations across the basin were analyzed and assessed with the Canadian (CCME) Water Quality Index. The mean water quality index for drinking, agriculture, and industrial purposes indicated that headwaters and higher areas generally exhibited better water quality compared to the downstream areas of the basin. Geochemical processes and the introduction of various pollutants during water flow from the headwaters to the basin outlet contribute to a decline in water quality. The highest water quality was observed in the Kabudval and Shirabad stations, whereas the Baghesalian station exhibited the lowest. For drinking water use, hardness, bicarbonate, and chloride were identified as variables contributing to water quality decline in the headwaters and upstream areas. However, these areas predominantly maintained a moderate to good quality for drinking purposes. Conversely, downstream areas experienced a significant deterioration in water quality with higher pollutant levels such as total dissolved solids (TDS), sulfate, and sodium, resulting in relatively poor to poor conditions. Approximately 60% of the stations in the basin had excellent water quality for agricultural use, with no limiting factors. Only three stations near the basin's outlet exhibited relatively poor to poor water quality due to elevated chloride levels, sodium adsorption ratio (SAR), and electrical conductivity. only 28% of hydrometric stations demonstrated good water quality for industrial use. Hardness, pH, and TDS are the main variables contributing to water quality decline for industrial use in the upstream, while downstream areas are impacted by chloride and sulfate. The outcomes of this study hold significant implications for effective water resources management, watershed preservation, and natural resource conservation in the Gorganrood basin. From industry and especially health aspects, however, more detailed investigations are needed, taking into account some other important variables of water quality (including nitrate, total coliform, fecal coliform, etc.).
E. Karamian, M. Navabian, M.h. Biglouei, M. Rabiei,
Volume 28, Issue 1 (5-2024)
Abstract
Cultivation of rapeseed as the second crop requires drainage systems in most of the paddy fields of the Guilan province. Mole drainage, as a low-cost and shallow drainage method that is suitable for rice cultivation conditions and easier to implement than pipe drainage, can be a solution in the development of second-crop cultivation. The present study was conducted to evaluate the drainage of mole drainage and nitrogen fertilizer management on the quantity and quality of drainage at Guilan University. In this regard, an experiment was conducted under two treatments including drainage and nitrogen fertilizer (i.e. traditional mole drainage and sand-filled mole drainage), and 180 and 240 kg of nitrogen fertilizer per hectare in three replications. After each rainfall during the plant growth period, water samples were taken from the drains, and parameters of electrical conductivity, pH, total suspended solids, total phosphorus, turbidity, concentrations of ammonium, chloride, nitrite, nitrate, and phosphate were measured. Also, the outflow from the drains and the water table level were measured by piezometers during the rain and after that. The results of the mean comparison of pH and total suspended solids showed that most of them were obtained with 7.49 and 281.25 mg/liter, respectively, in the mole drain filled with sand and the traditional mole drainage and 180 fertilizer treatment. The highest mean of electrical conductivity and turbidity was observed as 651 micro mohs/cm in the traditional mole drainage and 240 fertilizer treatment and with 67.76 NTU in the traditional mole drainage and 180 fertilizer treatment. The statistical analysis showed that the effect of drainage treatment on the amounts of ammonium, nitrite, nitrate, phosphate, and total phosphorus was not significant. The outflow from the traditional mole drainage was 49% lower than the sand-filled mole drainage. The traditional and sand-filled mole drains were able to drain excess water with average reaction coefficients of 0.8 and 0.83 per day during the growth period, respectively. Considering the speed of water discharge, drain discharge, and the main non-significance of qualitative parameters among drainage treatments, mole drainage filled with sand is recommended for the development of rapeseed cultivation in paddy fields.
M. Saeidi Nia, H. Mousavi, S. Rahimi Moghadam,
Volume 28, Issue 1 (5-2024)
Abstract
Due to the lack of water resources and excessive evaporation in the country, it is necessary to have a detailed irrigation program and a suitable management method. The present research was conducted to investigate the effect of superabsorbent and mulch in Khorramabad in July 2022 in a factorial combination with a completely randomized design in three replications. The first experimental factor was irrigation water treatment in 4 levels including irrigation that provided 100% water requirement (I100), 80% of crop water requirement (I80), 60% of crop water requirement (I60), and 40% of crop water requirement (I40). The second factor included different corrective materials including plant mulch (M), superabsorbent (S), and control treatment (I). The results showed the maximum amount of wet and dry yield and crop height was related to I100-M treatment, i.e. 100 percent water requirement and compost corrective material, which were 89.52 tons per hectare, 29.42 tons per hectare, and 2.27 meters. The maximum wet and biological productivity for I40-S was calculated as 14.24 kg of wet matter per cubic meter of water and 4.75 kg of dry matter per cubic meter of water. The lowest wet and dry yields were related to I40-M, which decreased the yield of the control treatment by 6.5 percent and 0.9 percent. The lowest productivity was related to the I100-S treatment, which was calculated as 3.13 kilograms per cubic meter of water for biological productivity and 9.14 kilograms per cubic meter of water for wet weight productivity. In general, mulch had a better performance in the treatments where the water stress was low, but when the water stress increased, the performance of the mulch treatments decreased. In the superabsorbent matter, the treatments with complete irrigation or with less stress, yield decreased, but the treatments with increased stress showed better results than most of the corrective materials and the control treatment.
Y. Choopan, H. Arianpour,
Volume 28, Issue 2 (8-2024)
Abstract
Reducing the effects of the misuse of urban wastewater is to use it in agriculture along with the subsurface irrigation system, which effects on the soil also require extensive investigations. Therefore, the present research was performed in a randomized complete block design with two factors of the type of irrigation source (well water W1 and treated urban wastewater W2) and the type of irrigation system (surface S1 and subsurface drip S2) in three replications (R) for a soil depth of 0-40 centimeter during two crop seasons. The results showed that the potassium, sodium, salinity, and sodium absorption ratio were significant at the 1% probability level in the comparison of system type and irrigation source type, whereas the values of pH, calcium, and magnesium were not significant in the comparison of system type and irrigation source type. The lowest value of calcium, magnesium, sodium cations, chlorine, phosphate, and sulfate anions was obtained in the W1S1 treatment. Also, the highest parameters of salinity, calcium, magnesium, phosphate, potassium, and chlorine were observed for the W2S2 treatment. It can be concluded that irrigation with urban wastewater has improved the chemical properties of the soil, and the type of irrigation system has had minor changes.
S. Esmailian, M. Pajouhesh, N. Gharahi, Kh. Abdollahi, Gh. Shams,
Volume 28, Issue 2 (8-2024)
Abstract
Studying the process of soil erosion and evaluating its effective factors is one of the most important prerequisites for proper management of soil and water resources. This study was conducted to investigate the production of surface and pipe runoff and sediment using artificial rainfall on silt loam soil in the laboratory. So, the soil was collected from the study area and transported to the laboratory. Laboratory experiments were performed on a soil bed in a rectangular flume with three pipes, at slopes of 2%, 6%, 10%, 14%, and 18% under simulated rain (30 mm/h) for one hour. Related graphs were drawn in Excel to analyze the results, and Spearman's correlation test was used in SPSS software to check the correlation between runoff and sediment values in each slope. The results showed that with the increase in slope, the sum of surface and pipe runoff and sediment increased over time. For example, in a slope of 2%, the runoff and sediment in the initial moments of the experiment increased from 0 to 1.3 liters and 26.2 g m-2 at the end of the experiment. Also, the correlation coefficient between runoff and sediment in the slopes was 0.98, 0.62, 0.4, 0.93, and 0.15, respectively, which was significant in some, but in others, it was not significant because of soil loss.
B. Moravejalahkami, N.a. Ebrahimipak, S. N. Hosseini,
Volume 28, Issue 2 (8-2024)
Abstract
Evapotranspiration variations (ET0) were investigated and analyzed using Minitab16 software for the 2010-2019 period using the Nizab system's data in Yazd province, and then ET0 was predicted until 2027. Based on the results, the increase of ET0 in cities of Yazd province was affected by the enhancement in wind speed and weather temperature, and the decrease in relative humidity from 2010 to 2019. To determine the appropriate model, Ardakan, Abarkooh, and Taft cities were selected as a representative in each climatic group, and ET0 data for the years 2010 to 2015 were considered as the input data of the software and ET0 data for the years from 2016 to 2019 were used to validate the determined model. The prediction of the determined models showed an increasing trend of ET0 for cold seasons in Ardakan and Abarkoh by 2027. Also, the model prediction showed a decreasing trend of ET0 for hot seasons in Taft by 2027. Also, the ET0 will not change significantly in cold seasons. In Abarkoh and Ardakan cities, autumn-spring crops such as wheat and in Taft city, spring-summer crops such as sunflower will be more affected by ET0 variations.
A.r Vaezi, Kh. Sahandi, F. Haghshenas,
Volume 28, Issue 3 (10-2024)
Abstract
Water erosion can be affected by land use change and soil degradation by agricultural activities. This study was conducted to investigate the effects of land use change in poor pastures on soil physical degradation and water erosion in semi-arid regions. Experiments were performed in 42 soil samples taken from seven areas covering the two land uses: poor pasture and rainfed agriculture, which have different soil textures (clay loam, silty clay loam, sandy clay loam, silt loam, loam, sandy loam, and sandy loam). The physical characteristics of soils were measured in the samples of both types of land use and its changes were expressed as physical degradation of the soil. The soil's susceptibility to water erosion was measured under simulated rainfall with 50 mm h-1 intensity for 60 min. The results showed that the land use change in pastures leads to the physical deterioration of soils; so bulk density, porosity, macropore, field capacity, saturated point, aggregate size, and aggregate stability were degraded with a rate of 28, 22, 41, 11, 5, 62, and 63 percentages. The structural characteristics of soil (aggregate size and stability) had the highest physical deterioration due to the land use change in the pastures. The change in land use change greatly increased the sensitivity of soils to water erosion. A significant relationship was found between the susceptibility of water erosion and the soil's physical degradation. The soils with coarser and more stable aggregates have higher physical degradation by the land use change and in consequence show more susceptibility to water erosion.
M. Barahimi, A.r. Sehhat, H. Kavand, S. Parvizi,
Volume 28, Issue 3 (10-2024)
Abstract
Today, many countries, including Iran, face natural hazards such as ground subsidence, drought, floods, and acute water shortage. Lack of correct management of underground water resources leads to many of these natural hazards. Artificial recharge of aquifers is one of the solutions proposed in the world to deal with these natural hazards, especially ground subsidence. The quantitative and qualitative effects of the effluent treatment plant on the Damaneh Daran Aquifer recharge were investigated in this research. The results showed that aquifer recharge through the distribution of effluents in the Damaneh Daran River has a positive effect on increasing the water level and releasing effluents in the river will enhance the water level in a larger radius regardless of the quality of the effluents. Based on the result of the present study, it is suggested that all the effluent treatment plants be allocated to aquifer balancing in the future. In the part of replacing wastewater with active wells, due to the lack of wells with industrial and green area use in this region, provided advanced wastewater treatment, all wastewater should be replaced with active wells in the agricultural area.
F. Afsharipour, M.r. Sharifi, A. Motamedi,
Volume 28, Issue 4 (12-2024)
Abstract
Drought monitoring in snowy basins requires modifications in common drought indices, called snow drought indices. The latest developed snow index is SZIsnow. The SZIsnow index calculating with special algorithm requires access to the values of 22 different climatic and physical variables, including soil moisture at a depth of 0 to 10 centimeters, soil moisture at a depth of 100 to 200 centimeters, air temperature, water equivalent to snow, runoff from snow melting, snowfall, rainfall, total precipitation rate, evaporation and transpiration, wind speed, surface runoff, groundwater runoff, potential evaporation, air pressure, relative humidity, net latent heat flux, ground heat flux, net sensible heat flux, evaporation from bare soil, evaporation from the canopy, and potential evapotranspiration. So far, the mentioned index has been calculated only on a continental scale. Drought monitoring at the basin scale is important as one of the management aspects of water resources. On the other hand, due to the lack of sufficient information to estimate the mentioned parameters, the use of information from global databases will be a solution. Therefore, in this research, while introducing the process of calculating the SZIsnow index, in the Dez catchment area, extracting the required parameters of the index in a time scale of 3, 6, and 12 months and a period of 41 years (1982 to 2023) using data GLDAS and then drought monitoring of the basin was studied. The results showed that the new SZIsnow index is a multi-variable index that provides the possibility of calculating the index due to the existence of parameters that lack ground observations and on the other hand, the availability of the reliable GLDAS database. Also, the results showed that in the time steps of 3, 6, and 12 months, July at -0.59, June at -0.45, and October at -0.35 had the highest amount of drought, respectively.
S. Zandi, S. Borumandnasab, M. Golabi,
Volume 28, Issue 4 (12-2024)
Abstract
Quinoa, a nutritionally rich crop with remarkable adaptability to unfavorable environments, exhibits a high tolerance to salinity. Reusing agricultural drainage water is a natural and important method in drainage management that increases farmers' income, sustainable production, and food security. The objective of this study was to investigate the effects of irrigation with agricultural drainage water, salinity stress, and water deficit on the yield and yield components of quinoa (Titicaca) under salinity levels of 2, 10, 15, and 20 dS/m and irrigation levels of full irrigation, 80%, and 60% of the crop water requirements. The experiment was conducted with three replications using a split-plot design with a randomized complete block design (RCBD) at the experimental farm of the Faculty of Water and Environmental Engineering at Shahid Chamran University of Ahvaz, during the fall and spring seasons of the years 2022 and 2023. The water requirement of Qinoa was determined gravimetrically by measuring soil moisture before each irrigation and increasing it to field capacity. The experimental treatments were imposed after seed germination and from the start of cultivation. The plants were harvested and transported to the laboratory for drying and yield component analysis upon physiological maturity. The results revealed that salinity stress had a more pronounced impact on reducing quinoa yield and yield components compared to water stress. The highest and lowest grain yields were observed in the autumn season, reaching 5.45 and 1.8 t/ha under the treatments of S1I1 and S4I3, respectively. Similarly, in the spring season, the highest and lowest grain yields were 3.87 and 0.73 t/ha under the same treatments, respectively.
R. Daneshfaraz, M. Majedi Asl, T. Omidpour Alavian,
Volume 29, Issue 1 (4-2025)
Abstract
Weirs play a crucial role in flood management and dam safety, accounting for a significant portion of the construction costs of dams. The selection of floods with long return periods for flood design is of utmost importance. However, in some cases, increasing the weir capacity by widening it may be impossible due to topographical limitations. One solution to enhance the flow capacity of weirs is the application of labyrinth weirs. These weirs increase the effective length of the weir crest within a given width, allowing for the passage of higher flow rates while maintaining similar hydraulic conditions. In this study, the hydraulic performance of labyrinth weirs is investigated using the Flow3D numerical model and laboratory data. Since laboratory experiments are time-consuming and costly, employing numerical simulations to achieve more accurate and reliable results for evaluating the hydraulic behavior of labyrinth weirs is prioritized. The results of the simulations indicate that the Flow3D software, utilizing statistical parameters such as R², DC, and RMSE, achieves values of (0.9805, 0.9725, and 0.0142), respectively. This demonstrates its capability to model the flow passing through weirs with high accuracy. The obtained values of the discharge coefficient in Flow3D show a high agreement with the laboratory data from Crookston. The approximate alignment of these results indicates the high accuracy of the numerical model. Additionally, in comparison to different discharges, the relative computational error observed for flow rates of 0.35, 0.6, and 0.44 (cubic meters per second) was approximately 0.5 percent, while for flow rates of 0.3, 0.4, and 0.57, the corresponding errors were 8, 6, and 4 percent, respectively. The results indicate that these tools can be effectively utilized in precise hydraulic analyses and the optimization of weir designs, irrigation systems, and fluid dynamics phenomena.
S. Ashkevari, S. Janatrostami, A. Ashrafzadeh,
Volume 29, Issue 1 (4-2025)
Abstract
In this study, a conceptual model based on dynamic systems was developed to optimize the management of water, land, and agricultural production (tea and rice) in the irrigation zones of the Sefidroud irrigation and drainage network. To understand the behavior of the network and create a simulation model of the system, a dynamic systems modeling approach was employed, and the simulation was conducted using MATLAB/Simulink. Subsequently, the optimization model of the studied system was developed as a multi-objective model using a genetic algorithm. Various management scenarios were implemented through the weighting of the objective functions. The results showed that selecting the best response from multi-objective optimization models depends on the weighted values of the objective functions, and by changing these values, decision-makers can provide various responses to complex optimization problems. The optimization model determines the cultivated area and water allocation in such a way as to minimize water scarcity and maximize crop performance through different weighting combinations. Furthermore, the findings indicate that the canals of the irrigation network play a crucial role in meeting water needs, and equitable water allocation is essential to prevent excessive extraction and negative consequences, such as saline intrusion and land subsidence. The study demonstrates that the best solutions are contingent upon local conditions and decision-makers' policies. To achieve maximum economic benefits and address water needs, it is suggested to use a weighting combination close to (w1=1,w2=2). Ultimately, this model assists managers and decision-makers in minimizing water scarcity in the region by adjusting cropping levels and optimizing the use of available water resources.
J. Karimi Shiasi, F. Fotouhi Firoozabad, A. Fathzadeh, M. Hayatzadeh, M. Shirmardi,
Volume 29, Issue 1 (4-2025)
Abstract
One of the main factors contributing to water erosion is the inherent characteristic of soil erodibility. Erodibility depends on particle size distribution, organic matter, structure, and soil permeability. This research aimed to investigate changes in the soil erodibility factor across geomorphological facies. The soil erodibility index was estimated by sampling 58 points within the geomorphological facies of the Dorahan watershed, using the Wischmeyer and Smith method. In the laboratory, soil granularity distribution, organic matter, soil structure, the amount of gravel, lime, salinity, acidity, and sodium absorption ratio were measured. Results indicated that soil erodibility across the entire area ranges from 0.0148 to 0.0661 (t.hr/Mj.mm). The soil erodibility index (K) for the hro-p1 and hro-p2 facies is higher than for others and exhibits the widest range of variations compared to the other facies. The lowest range of changes within geomorphological facies is associated with the hrc facies. The erodibility index decreases from the east to the west of the basin due to the presence of exposed rock faces, which protect the soil as a cover layer.
A. Mirzaei, A. Soltani, F. Abbasi, E. Zeinali, Sh. Mirkarimi,
Volume 29, Issue 1 (4-2025)
Abstract
Water scarcity and adaptation to it are the most significant issues facing Iran's agriculture. Optimizing the cropping pattern is one of the fundamental strategies for addressing water scarcity. This study evaluated the optimization of the cropping pattern in the irrigated lands of Fars province, one of Iran's key agricultural production areas. Linear mathematical programming and the SAWA system (System for Provincial Agricultural Water Balance and Accounting) were employed. The optimal cropping pattern (OCP) was designed to minimize applied irrigation water and was compared with the current cropping pattern (CCP) as well as a proposed cropping pattern from the Agricultural Jahad Organization (CPAJO) for the province for the cropping year 2023-2024. The results indicated that in the OCP, compared to the CCP, the cultivated area for the following crops decreased: wheat by 30%, barley, grain maize, silage maize, alfalfa, sugar beet, potato, cold- season legumes, and cold-season oil crops by 60%, rice by 80%, warm-season fruit trees by 42%, and vegetables by 13%. Conversely, the cultivated area for warm-season legumes and cold-season fruit trees each increased by 60%, while cold-season legumes increased by 150%. To meet the adaptation goals for water scarcity and sustainable agriculture outlined in this study, a 24% reduction in the irrigated cultivation area of the province was deemed necessary. The OCP achieved a 34% reduction in applied irrigation water at the provincial level without decreasing farmers' income. Compared to the CCP, the OCP led to a 32% reduction in the amount of plant production (by weight) at the provincial level. However, prioritizing plants with higher gross economic profit and lower water consumption over those with lower gross economic profit and higher consumption resulted in the gross economic return of the OCP being comparable to that of the CCP and the CPAJO. The comparison of OCP with CPAJO indicated that the CPAJO has not seriously considered adaptability to water scarcity or agricultural sustainability. The CPAJO needs to be reviewed and optimized to address water scarcity and ensure production stability in light of the impacts of excessive water withdrawal in the province.
B. Naderi-Samani, M. Ghobadinia1, B. Haghighati, S.m.r. Hosseini-Vardanjani, A.r. Ahmadpour-Samani,
Volume 29, Issue 1 (4-2025)
Abstract
Awareness of the impact of water deficit stress on the quantitative and qualitative performance of agricultural products, considering the recent recurrent droughts and reduced precipitation, is essential for water consumption management. This study aimed to evaluate the effects of different irrigation deficit treatments on the yield, yield components, and water use efficiency of autumn wheat in the Shahrekord region. An experiment with three replications was conducted in a completely randomized block design at the Agricultural and Natural Resources Research Center of Chaharmahal Va Bakhtiari Province during 2023-2024. The experimental treatments included four irrigation levels: full irrigation (T100), 80% of full irrigation (T80), 60% of full irrigation (T60), and 40% of full irrigation (T40). The application of the T60 deficit irrigation treatment resulted in a reduction of more than 14% in grain yield, while the T80 treatment caused a more than 31% decrease in grain yield. Additionally, the T60 treatment exhibited the highest water use efficiency at 1.22 kg per cubic meter, while the water use efficiency for the T100, T80, and T40 treatments was 1.06, 1.12, and 1.19 kg per cubic meter, respectively. The results showed that water deficit irrigation significantly affected the grain yield, biomass, and water use efficiency of autumn wheat under the climatic conditions of the Shahrekord region. The results of this study indicated that the T80 deficit irrigation treatment could have a more acceptable performance in terms of water efficiency.
I. Saleh, S. Zandifar, M. Khazaei,
Volume 29, Issue 2 (7-2025)
Abstract
Groundwater resources are affected by long-term drought conditions and have received less attention than other issues. The current research was carried out to investigate and zone the quantitative fluctuations of groundwater as well as the temporal analysis of groundwater drought using GRI in the study area of Shiraz in the Maharloo-Bakhtegan watershed. The zoning of groundwater table variations was done in the ArcGIS environment, and a representative hydrograph of the aquifer was prepared using 15-year data (2003-2018) of groundwater resources divided into three five-year periods. Also, the drought of the groundwater resources of the studied plain was investigated using the GRI index. According to the results, the highest level of the groundwater table is related to the northwestern area of the plain by 1810.1 m in October 2007, and the lowest water table was observed in the southern study area with the amount of 1423.6 m in October 2017. Also, the results showed that the groundwater table faced a drop of 6 m and an average annual drop of 0.5 m during the studied 15 years. The volume changes of the reservoir also indicated that, in addition to consuming the entire renewable reserve, a large part of the fixed reserve has also been exploited in the past years. The descending trend of GRI and its intensification in the last years of the studied period is one of the most important results of this research, which occurred due to population growth and increasing cultivated area, a decrease in precipitation, and climate change.
M. Khoshoei,
Volume 29, Issue 2 (7-2025)
Abstract
The issue of water scarcity or the limited availability of water resources, including concepts such as water stress, water shortage, and water crisis, is investigated in this study. Water stress refers to problems related to access to freshwater resources, particularly due to the excessive withdrawal of surface and groundwater. A water crisis describes a situation where the available clean and safe drinking water in a specific region is insufficient to meet demand. Factors like drought, reduced rainfall, and pollution can exacerbate water stress. Water shortage arises from reasons such as the inability to meet demand, economic competition over water quality and quantity, conflicts among users, the irreversible depletion of groundwater resources, and negative environmental impacts. This study provides an index to assess water stress for spatial analysis in the study area and analyzes relevant data by collecting information from various sources. This index utilizes both static and dynamic parameters to estimate drought and better depict water stress conditions. Static parameters include land use, slope, and soil type. Dynamic parameters include precipitation, temperature, and groundwater level. Kashan County was selected as the case study due to the continuous reduction in water resources. The results showed that in the water years 2005, 2014, 2020, and 2021, Kashan experienced the highest level of water stress, while in the water years 2002, 2004, 2010, 2012, 2013, and 2015, it experienced the lowest level of water stress.
