1
reza saeidi; AbdolMajid Liaghat
Abstract
This research aimed to simulate the yield of maize cv. S. C 704 under conditions of separate application of salinity stress at different growth stages in mini-lysimeter, in Qazvin area, Iran. The experiment was performed as factorial and in a completely randomized design. Soil salinity treatments, as ...
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This research aimed to simulate the yield of maize cv. S. C 704 under conditions of separate application of salinity stress at different growth stages in mini-lysimeter, in Qazvin area, Iran. The experiment was performed as factorial and in a completely randomized design. Soil salinity treatments, as the main factor, included four levels of 1.7(S1), 3(S2), 5(S3) and 7(S4) dS.m-1. The sub-factors included different growth stages as follows: one-stage at 6-leaves (C1), flowering (C2), and milk stage (C3); and two-stages of C1C2, C1C3 and C2C3. By combining saline water (from a salt marsh) with a well fresh water (0.5 dS.m-1), saline water was prepared according to the treatments. Irrigation was done in a way that the salinity of input and output water from the mini-lysimeters was equal. The control treatment was irrigated with fresh water. By combining the water uptake reduction functions, the derived models were presented and evaluated for simulating yield reduction coefficient (α). The stress application data in one and two-growth stages were used for models calibration and validation, respectively. Applying the highest salinity level led to decrease in dry matter yield from 157.2 g. plant-1 (in S1 treatment) to 115.9, 53.2, 77.7, 86.1, 97 and 46.5 g. plant-1 in the C1, C2, C3, C1C2, C1C3 and C2C3 treatments, respectively. The results showed that crop sensitivity was different in one-stage and two-stage stress application. Salinity stress at flowering (C2) and milk stage (C3) had a more negative effect relative to C1C2 and C1C3. In this research, Van Genuchten's additive model and Dirksen-Maas-Hoffman's multipliable model could be recommended as the optimal models for crop yield simulation. Also, application of two-stage salinity stress (up to level of 7 dS.m-1) in C1C2 and C1C3, had higher yield relative to application of one-stage stress in C2 and C3 growth stages.
6
Razieh Bayani; Mojtaba Khoshravesh; Abdolmajid Liaghat; Masoud Pourgholam-Amiji
Abstract
Due to the drought, water and food security in the country is facing serious challenges, and a precise and science-based implementation plan is needed. The use of new technologies, such as modern irrigation systems, is essential as an effective tool for optimal water use. Therefore, this study was conducted ...
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Due to the drought, water and food security in the country is facing serious challenges, and a precise and science-based implementation plan is needed. The use of new technologies, such as modern irrigation systems, is essential as an effective tool for optimal water use. Therefore, this study was conducted to investigate the yield, yield components, and water efficiency of rice variety "Honda" in two surface and subsurface drip irrigation systems in a paddy field located in Kiasar, Mazandaran Province, Iran, during the spring and summer of 2022. The experimental design was strip plots using a randomized complete block design with 6 treatments and 3 replications in 18 plots measuring 2 by 3 m. The treatments included surface drip irrigation with strip distances of 25, 50, and 75 cm, and subsurface drip irrigation at a depth of 30 cm with the same strip distances. The results showed that cluster length, number of grains, plant height, and root length were significantly increased in surface drip irrigation treatments compared to subsurface treatments, with an increase of 1.2 cm (6.8%), 8.19 (49.8%), 6.9 cm (8.2%), and 1 centimeters (6.9%), respectively. The grain yield, harvest index, physical efficiency, and economic efficiency in the surface drip irrigation treatments showed significant increases of 1664 kg/ha (40.8%), 4.7% (14.1%), 0.27 kg/m3 (38.5%), and 242,363 Rials/m3 (38.4%), respectively, compared to subsurface drip irrigation treatments. The maximum grain yield and harvest index were observed at distances of 25 cm, equal to 5834 kg/ha and 40%, respectively. The maximum physical efficiency was observed at a distance of 50 cm, equal to 0.93 kg/m3. With an increase in distance between the strips from 25 to 50 cm, the physical efficiency increased by 22%. However, further increase in the distance led to a decrease in physical efficiency. The maximum economic efficiency was observed for surface drip irrigation at a distance of 50 cm, equal to 836,951 Rials/m3.
6
Masoud Pourgholam-Amiji; Khaled Ahmadaali; Abdolmajid Liaghat
Abstract
This research aimed to select essential features for modeling the cost of pressurized irrigation systems using the data of 515 drip irrigation projects in four parts, including the cost of pumping station and central control system (TCP), cost of on-farm equipment (TCF), cost of installation and operation ...
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This research aimed to select essential features for modeling the cost of pressurized irrigation systems using the data of 515 drip irrigation projects in four parts, including the cost of pumping station and central control system (TCP), cost of on-farm equipment (TCF), cost of installation and operation on-farm and pumping station (TCI), and total cost (TCT). In the first stage, a database including 39 features influencing the cost of the mentioned sectors was prepared and the price of all projects (2006 to 2019) was updated for the base year of 2021. Then, feature selection was done with different algorithms in MATLAB environment and in two parts including (1) all features (39 features before and after the design stage) and (2) 18 features before the design phase (BD). The results showed that the amounts of RMSE and R2 for all the features were equal to 0.007 and 0.92, respectively, and for the BD section, they were equal to 0.003 and 0.89, respectively. Among the different algorithms for feature selection, support vector machine (SVM) and optimization algorithms (Wrapper) were identified as the best learner and feature selection method, respectively. The results of the evaluation criteria showed that the two LCA and FOA algorithms achieved the best estimation, and their error criterion in all the features were 0.0020 and 0.0018, respectively, while their correlations were 0.94 and 0.94. In the BD features, these criteria were 0.0006 and 0.95 for both algorithms, respectively. Finally, in the all features section, 10 out of 39 features and for BD section, 8 out of 18 were selected as the most effective features. The results of choosing the most effective features that affect the cost of different parts of the drip irrigation system can make the cost modeling of the systems simpler and faster and, while being useful for research works, it facilitates estimation and management of costs before implementation of each project.
Mohammad saeid Jafari; Hamideh Noory; Abdol-Majid Liaghat; Hamed Ebrahimian
Abstract
Lettuce is one of the most important leafy vegetables used primarily for fresh and salad applications. The purpose of this study was to investigate the effect of different levels of water and nitrogen on lettuce yield and find the best irrigation and nitrogen fertilizer practices for producing this crop ...
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Lettuce is one of the most important leafy vegetables used primarily for fresh and salad applications. The purpose of this study was to investigate the effect of different levels of water and nitrogen on lettuce yield and find the best irrigation and nitrogen fertilizer practices for producing this crop in drip irrigation. Iceberg variety of lettuce was planted in 2018 with three irrigation treatments (I1, I2 and I3 to provide 100%, 80%, and 60% of crop evapotranspiration, ETa, respectively) and four nitrogen treatments (N1, N2, N3, and N4 to provide 105, 70, 35 and zero kg of nitrogen per hectare in total, respectively). In 2019, two irrigation treatments (I1 and I3) and two nitrogen treatments (N1 and N4) were used. The experiment had a randomized complete block design with three replications. The results indicated that the effect of irrigation and nitrogen treatments and their interactions on the marketable yield of lettuce; but the dry matter produced was only affected by irrigation and nitrogen treatments. Maximum marketable yield and dry matter production were 66.1 ton.ha-1 and 2728.2 kg.ha-1 for full irrigation treatment with 105 kg.ha-1 nitrogen (I1N1) treatment, respectively. The minimum marketable yield and dry matter were 37.5 ton.ha-1 and 1929.6 kg.ha-1 for 60% ETa treatment with 35 kg.ha-1 nitrogen (I3N3) treatment, respectively. The maximum and minimum irrigation water productivities for marketable yield were 21.63 and 15.38 kg.m-3 for I2N1 and I3N3 treatments, respectively. The linear and nonlinear production functions of yield-water and yield-nitrogen were obtained for lettuce variety Iceberg, which can be used in similar environmental conditions in research and practical applications.
Ali Akbar Azizi Zohan; Abdolmajid liaghat; Mehdi Shahabifar
Abstract
In order to complete and differentiate various water productivity indexes according to the actual situation, it is necessary to provid a measure to evaluate the suitability of the productivity index and extend the results to other areas. Therefore, in this study, through a process view of the agricultural ...
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In order to complete and differentiate various water productivity indexes according to the actual situation, it is necessary to provid a measure to evaluate the suitability of the productivity index and extend the results to other areas. Therefore, in this study, through a process view of the agricultural production system and considering climate, land, and plant capabilities and constraints in the complex cycle of water-soil-plant-atmosphere and human, different water productivity (WP) researches were grouped and analyzed. Indices of Potential Climatic Water Productivity (PCWP), Potential Land Water Productivity (PLWP), Actual Water Productivity (AWP), Water Productivity Gap (WPG), Water Productivity Management Index (WPMI), and Water Productivity Management Level (WPML) were all defined and their methods of determination were presented. The indices were determined and analyzed for three forage maize farms in Moghan Plain. The results showed that changes in agronomic calendar and field soil conditions variation affected the PCWP and PLWP indices, such that the PCWP varied from 31 to 46 kg.m-3 in farms 1 and 3 and PLWP varied from 26 to 42 kg.m-3 in farms 2 and 3. The AWP was always less than the PLWP and was affected by farm management on yield, and the proportional of allocation and consumption of water to actual yield. The AWP was 27, 24 and 39 kg.m-3 for farms 1, 2 and 3, respectively, in the best condition. Where water allocation was location-specific and according to crop calendar and actual production, the WPG was drastically reduced and it was equal to 0.2, 2.2 and 3.5 kg.m-3 for farms 1, 2, and 3, respectively. Practically, using simply the AWP index cannot properly judge, analyze, and compare the status of water productivity management in different field conditions. However, The WPMI and WPML dimensionless indices presented in this article are suitable for this purpose.[1] [1] - Part of this research was funded by Project No. 2-10-10-096-961738, Soil and Water Research Institute (SWRI).
Masoud Pourgholam Amiji; Addolmajid Liaghat; Arezoo Nazi Ghameshlou; Mojtaba Khoshravesh
Abstract
The problem of soil salinity exists in the paddy field areas in Iran, especially in the Caspian Sea coastal areas, due to its proximity to the sea and low altitude with saline and shallow water table. Besides, considering that rice is one of the most important strategic crops for economy of Iran ...
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The problem of soil salinity exists in the paddy field areas in Iran, especially in the Caspian Sea coastal areas, due to its proximity to the sea and low altitude with saline and shallow water table. Besides, considering that rice is one of the most important strategic crops for economy of Iran and the people in this area, this research was necessary in order to investigate the possibility of production of rice in the presence of shallow and saline groundwater table. This research was performed as a physical model (insulated metallic lysimeter) in the Meteorological Research Center of College of Agriculture and Natural Resources, University of Tehran, in 2017. The complete randomized design included two treatments with shallow water table: FSG and SSG, with fresh (control) and saline water, respectively. The salinity of irrigation water was 0.94 dS/m for both treatments. Moreover, for SSG treatment, the EC of shallow groundwater was 20 dS/m at 40 cm soil depth and was regulated as an artificial recharge. The results of salinity profile in SSG treatment showed that there was almost no mixing of fresh and saline water in interstitial zone (under the hard pan from 30 cm to 40 cm of soil surface). In this manner, there was insignificant effect of salinity in the root zone, because of existing of permanent water layer in rice field and downward water flow, which makes an obstacle for upward flow for saline water. This problem did not affect the rice yield, which didn’t decrease. The results of data analysis confirm this and show that shallow groundwater salinity has no significant effect on the parameters like leaf area index (LAI), root length (RL), plant length (PL), membrane stability index (MSI), chlorophyll (SPAD), relative water content (RWC) and the biomass (BIO). The difference between the performance of the control and the salinity treatments was about 1 to 12 percent, while the grain and biological yield in SSG treatment compared with FSG treatment decreased 3.2% and 4.5 percent, respectively. Therefore, considering the significant leaching of soil after cultivation, the negligible loss of yield and upward movement of saline water in the soil, production of rice and other plants in such areas seems possible. Also, with the help of efficient and effective use of lands with shallow saline groundwater, we can decrease the pressure on conventional soil and water resources.
Hamed Nozari; Azin Poursadri; Saeed Azadi; abdolmajid liaghat
Abstract
After installing subsurface drainage system, quality of drainage water in saline lands continuously changes, starting from the beginning of irrigation and drainage network operation, until reaching a more or less equilibrium state. Reaching a state of equilibrium in areas with saline groundwater may ...
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After installing subsurface drainage system, quality of drainage water in saline lands continuously changes, starting from the beginning of irrigation and drainage network operation, until reaching a more or less equilibrium state. Reaching a state of equilibrium in areas with saline groundwater may take several years. In this regard, field experiments are useful but they also have significant limitations. As an alternative, simulation models are among the methods that greatly eliminate these limitations. Therefore, in this research, the performance of DRAINMOD-S model was evaluated in simulation of drainage volume, drainage water salinity, and water table fluctuations. To validate the results of the model, data collected in the 2007-2008 cropping year from ARC18-18 farm was used in the research site of Sugarcane Research Center (Amir Kabir Agro Industrial Development Unit of Sugarcane Development Company, Khuzestan Province). This information included meteorological and soil data, drainage outflow, irrigation water salinity, water salinity within piezometers, and drainage water salinity. After statistical analysis and calculating the root mean square error (RMSE) and standard error (SE), the fits between the measured and simulated values of drainage water salinity, groundwater salinity, water table fluctuations and drainage discharge were investigated. The RMSE statistical index was 4.76 dS /m for drainage water salinity, 0.82 dS/m for groundwater salinity, 21.2 cm for groundwater surface and 2.1 L/s for the drain discharge, which indicated a fairly good accuracy compared with actual conditions. The results showed that the model was capable of simulating the water level fluctuations, drainage outflow and its salinity in Khuzestan region with saline and shallow groundwater table.
maryam alizade; peyman afrasiab; mohammad reza yazdani; abdolmajid liaghat; Masoomeh Delbari
Abstract
In rice cultivation, mid-season and end-season drainage at harvest time are two important operations of water management which, respectively, increase yield and provide better conditions for harvesting rice. Due to the unique conditions of paddy fields of Guilan province, making decisions about ...
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In rice cultivation, mid-season and end-season drainage at harvest time are two important operations of water management which, respectively, increase yield and provide better conditions for harvesting rice. Due to the unique conditions of paddy fields of Guilan province, making decisions about the spacing and depth of drains and proper equation to determine the drainage spacing in paddy field requires research on the mid-season and end-season drainage. Therefore, in this research, the efficiency of drains spacing (L) and depth (D) of subsurface drainage in controlling water table and also accuracy of the steady and non-steady equations were evaluated at mid-season and end-season drainage stages in Guilan’s rice fields. Drainage treatments included six conventional subsurface drainage systems with rice husk envelope including drainage system with drain depth of 0.8 m and drain spacing of 7.5 m (L7.5 D0.8), (L10 D0.8), (L15 D0.8), (L7.5 D1), (L10 D1), and (L15 D1). All drain lines were 40 m long and made of PVC corrugated pipes with a diameter of 125 mm. Results showed that subsurface drainage with spacing of 15 m and depth of 80 cm (due to the proper water table depth and higher yield) and subsurface drainage with distance of 10 m and depth of 80 cm (due to the highest resistance to pentrometer penetration and the lowest soil moisture content) are recommended as the best drainage treatment for mid-season and end-season drainage, respectively. Dagan, Hooghoudt and Bouwer & Van Schilfgaarde equations combined with Hooghoudt equation were suitable equations for determining drainage spacing at mid-season drainage stage. Hooghoudt, Kirkham, Dagan, Bouwer & Van Schilfgaarde equations combined with Hooghoudt equation and Glover-Dumm equation were selected as suitable formulas for determining the spacing of subsurface drains for end-season drainage.
H J; A L; A H
Abstract
Reuse of treated municipal wastewater in agriculture and artificial recharge of aquifers in arid and semi-arid regions are of great interest to water resources specialists. In the use of treated wastewater for artificial recharge operations, the fate of substances added to the soil by wastewater transmission ...
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Reuse of treated municipal wastewater in agriculture and artificial recharge of aquifers in arid and semi-arid regions are of great interest to water resources specialists. In the use of treated wastewater for artificial recharge operations, the fate of substances added to the soil by wastewater transmission of pollutants to the aquifer depth and movement is very important, because they may cause contamination of soil and groundwater resources. In this study, an L-shaped cylindrical column, made of PVC with a diameter of 30 cm was used to simulate the vertical movement of water and its movement in the shallow groundwater layer during artificial recharge operations. Horizontal sections along the vertical length were 300 cm and 250 cm. The column was filled with a sandy loam soil and the treated wastewater of Mahdasht treatment plant located in Alborz Province was used for artificial recharge operations. During the test period, the effect of management strategy of permanent water logging for 40 days and a dry period for the removal of wastewater pollutants in the soil column were examined. Values of BOD5, COD, EC, coliform, fecal coliform, phosphorus and nitrate in water samples collected from the inlet and the path length were measured at one meter intervals. The results indicated the high efficiency of removing pollutants in the soil column, while the nitrate removal efficiency and EC changes were low. The values of BOD5, COD, EC, coliform, fecal coliform, phosphorus and nitrate in the best of cases were 96.4%, 91.8%, 15.4%, 99.3%, 99.4%, 92.4% and 17.2%, respectively. A comparison with National Guides of Iranian Environmental Protection Agency shows that the outflow of artificial recharge system can be used for irrigation of agricultural crops. However, it is to be noted that, generally, use of wastewater for irrigation of food crops is not recommended.
m a; p a; m y; a l; m d
Abstract
A second crop in paddy fields has economic advantages resulting from the production of crops (canola, beans, garlic, triticale, soybean, etc.), Preparation of rice bed for mechanized harvesting, strengthening the economy of farmers’ families, increase the incentive for farmers to stay in the village, ...
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A second crop in paddy fields has economic advantages resulting from the production of crops (canola, beans, garlic, triticale, soybean, etc.), Preparation of rice bed for mechanized harvesting, strengthening the economy of farmers’ families, increase the incentive for farmers to stay in the village, etc. Due to the inability of the existing surface drainage systems in rapid depletion of water from the root zone, conditions for planting a second crop in paddy fields is not suitable. This can be provided by installing subsurface drainage systems, which, in addition to creating more favorable conditions for planting and harvesting rice, allows cultivation of other crops in the wet season. This research was conducted to determine the appropriate space and depth of subsurface drainage in paddy fields in order to provide favorable conditions for planting a second crop. The experiment was laid out in one and a half hectares of paddy fields at Rice Research Institute of Iran in Guilan province, in 2014. Drainage treatments included: six conventional subsurface drainage systems with rice husk envelope including drainage system with different drain depth and spacing L7.5 D0.8, L10 D0.8, and L15 D0.8, L7.5 D1, L10 D1, and L15 D1, surface drainage, and the control (without drainage). All lines were 40 meters long and made of PVC corrugated pipes with a diameter of 125 mm. Rice husk was used as a covering around the pipe drain. The results showed that subsurface drainage spacing of 15 m had failed to lower the water table depth to an acceptable level and provided the conditions only for the cultivation of shallow-rooted plants such as dill, parsley, and leeks. Also, surface drainage could reduce the excess water in the soil by 22% compared to control. To provide suitable conditions for the cultivation of second crops such as canola and beans, subsurface drainage spacing of 7.5 and 10 m seemed effective. However, to avoid excessive drainages by 7.5 m spacing, subsurface drainage spacing of 10 m was selected as the best space at drainages stage, for a second crop. Furthermore, due to the lack of significant differences in water table depth between treatments L10D1 and L10D0.8,theywere identified as suitable drainage systems at 0.8 m depth.
b n; a l; m p; s b; h a
Abstract
Energy consumption and energy cost in irrigation systems have been important issues due to energy charge increase in recent years. In this study, theoretical basis of pressurized irrigation systems management and technical factors that affect energy costs were studied and the optimum system design criteria ...
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Energy consumption and energy cost in irrigation systems have been important issues due to energy charge increase in recent years. In this study, theoretical basis of pressurized irrigation systems management and technical factors that affect energy costs were studied and the optimum system design criteria for energy consumption were identified. In addition, energy consumptions of 45 pressurized irrigation systems in Qazvin province were evaluated. These irrigation systems types were classic sprinkler, center pivot, linear move, and trickle. The energy requirements of these systems for supplying a unit volume of water were obtained as 0.290, 0.250 and 0.202 KWh/m3, respectively. The results show the importance of irrigation systems selection in energy costs saving in national and regional plans. At last, energy consumption and related costs for various pressurized irrigation systems were studied for the main crops in Qazvin irrigation network. These results can be useful in deciding cropping pattern and economic studies.
Meysam Ramezani; Shokoofeh Salehi; Abdolmajid Liaghat; Mohammad Ali Gholami Sefidkouhi
Abstract
Soil water retention curve (SWRC) is necessary for many studies, such as unsaturated hydraulic conductivity and solute transport in porous media. However, its direct measurement is time consuming and expensive. In this study, an optimization method was developed in order to estimate soil water retention ...
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Soil water retention curve (SWRC) is necessary for many studies, such as unsaturated hydraulic conductivity and solute transport in porous media. However, its direct measurement is time consuming and expensive. In this study, an optimization method was developed in order to estimate soil water retention curve from limited measured points, such as water contents at field capacity and permanent wilting point. The main advantage of this method is that it is database independent. Three data sets including 156 soil samples from Belgium and Iran were used. Using van-Genuchten water retention model with restriction m=1-1/n and assuming residual water content to be equal to zero, vG model parameters such as and were optimized using two measured points and, consequently, SWRC was estimated (proposed method). Bulk density was used in order to estimate porosity in this method. In addition to the proposed method, ROSETTA model was applied to estimate vG model parameters and SWRC from sand, silt, and clay contents, bulk density, and water contents at field capacity and permanent wilting point. The MR, RMSE and AIC values for the proposed method were -0.00084, 0.031 and -8636 (cm3.cm-3) and for ROSETTA method were -0.037, 0.051 and -7327 (cm3.cm-3), respectively. Comparison of estimated SWRC using the proposed and ROSETTA method showed that the developed optimization method estimated SWRC more accurately than ROSETTA model.
Hamidreza Javani; Hassan Ojaghloo; Abdolmajid Liaghat
Abstract
Direct measurement of soil water retention curve parameters is hard, costly, and sensitive. One of the good indirect methods in prediction of soil water retention curve is Arya-Paris model, which uses the soil particle size distribution (PSD) data. The AP model estimates pore radius ( ri ) from the radius ...
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Direct measurement of soil water retention curve parameters is hard, costly, and sensitive. One of the good indirect methods in prediction of soil water retention curve is Arya-Paris model, which uses the soil particle size distribution (PSD) data. The AP model estimates pore radius ( ri ) from the radius (Ri) of spherical particles by scaling pore with a parameter α. In this study, data from soil particle-size distribution, soil water retention curve, bulk density, and porosity of 96 different soils including sandy, loamy sand, sandy loam, and silty loam were used to help assessing methods of estimating the scale parameter. The values of scaling parameter obtained from the inverse method for the sandy, loamy sand, sandy loam, and silty loam were 1.32, 1.36, 1.45, and 1.23, respectively. Use of the linear method for sandy and silty loam soils resulted in α values of 1.34 and 1.25, respectively, while, by using the constant method (recommended by Arya et al) for sandy loam and loamy sand, α values were1.37 and 1.46, respectively, which were the closest to the real calculated values. By studying the variations of α in different soil textures and moisture contents, it was noted that there was no significant relationship between α and the amount of sand in the soil. However, increase in the soil moisture increased the value of α while the correlation coefficient for α and soil moisture was calculated at 0.45.
h ramezani; a liaghat; m parsinejad; m ramezani
Abstract
Agricultural drought occurs when soil moisture is less than that required for the optimized production and damages crop yield. Drought indexes are used for monitoring purposes and in some of these indicators rainfall data are used. But, agricultural droughts indexes use soil moisture data. ...
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Agricultural drought occurs when soil moisture is less than that required for the optimized production and damages crop yield. Drought indexes are used for monitoring purposes and in some of these indicators rainfall data are used. But, agricultural droughts indexes use soil moisture data. Among the most important drought indexes that use soil moisture as input parameter, soil moisture drought index (SMDI) can be noted. Generally, mathematical models are used for soil moisture estimation. The objective of this study was to estimate soil moisture using AquaCrop model and to calculate SMDI with this estimation and compare it with the rainfall-based drought indexes such as PNI, DI, SPI and CZI, using Qazvin synoptic station data of 1982-2008. The results of soil moisture estimation using AquaCrop showed that monthly changes in soil moisture at 5 cm depth were very strong. With increasing depth, soil moisture changes were less and remained constant after 40 cm of depth. Average values of SMDI, PNI, DI, SPI and CZI were, respectively, 0.41.2, 10026.2, 0.042.6, 0.01.0, and 0.01.0. Based on SMDI, the wettest year was 1994 while the driest years were 1997, 1999 and 2008. But, based on other indexes, the wettest and driest years were 1982 and 2008. The main point for SMDI is that, in addition to the current season soil moisture conditions, the index uses soil moisture conditions of the previous year to calculate SMDI. According to our results, SMDI had low coefficient of determination with the other drought indexes, rain, and evaporation.