Showing 7 results for Ground Water
A. Mahdavi , M. R. Nouri Emamzadei, R. Mahdavi Najafabadi, S. H. Tabatabaei,
Volume 15, Issue 56 (7-2011)
Abstract
In recent years, surface water resources in Chaharmahal and Bakhtiari province have decreased and groundwater level has fallen down. Thus, groundwater must be strengthened by surface water resources. The objective of this search was identification of artificial recharge sites thorough Fuzzy Logic in Shahrekord Basin. Effective factors in ground water recharge such as slope, infiltration rate, thickness of unsaturated zone, surface water EC, land use and stream network were determined. They were classified, weighted in software packages Arc View 3.2a and Arc GIS 9.3 and they were integrated using multiplying operator in fuzzy model. The obtained results showed 4.79 % of all areas are suitable and 17.94 % are somewhat suitable in this method. To include the effect of land use parameter, it was overlaid on the final maps, showing a decrease in suitable areas up to 1/3. Generally about 30 points were introduced with priorities A, B, AB as having potential for artificial recharge.
S.h. Tabatabaei, M. Ghazali ,
Volume 15, Issue 57 (10-2011)
Abstract
The accuracy and precision of the input data in decision making is important. Error originates from data collection, data entry, storage, retrieval and analysis of the data which consequently result in model error. One of the errors in spatial analysis is interpolation error. The main objective of this research was the suitability assessment of some interpolation methods for estimation of groundwater level in Farsan-Joneghan and Sefiddasht aquifers, located in Beheshtabad catchment, Chaharmahl-Va-Bakhtiyari province, Iran. Cross-validation technique was employed for the determination of each method's error. The RMSE and MAE indices were used for the error comparison. The results show that the modified Shapard's method with an MAE=6 and RMSE=7 was the most accurate for interpolation of groundwtaer level in the Sefiddasht aquifer. The inverse distance power method with MAE=6 and RMSE=9 was the best interpolation method for Farsan-Jonaghan aquifer. The Kriging with MAE=7 and RMSE=12 is the second best method in these aquifers. The moving average, minimum curvature and polynomial regression procedures produce the maximum error in the aquifers (17
H. Zare Abyaneh, H.noori, A.m.liaghat, V.karimi, H.noori,
Volume 15, Issue 57 (10-2011)
Abstract
Fertilizers in agriculture are potential sources of environmental pollution, especially in ground water quality and soil resources. Studying factors effective in water and nutrient transport through soil profile is helpful for nutrient management to minimize adverse impacts on environment and nitrate leaching below the root zone. In this study, the ground water level and nitrate leaching transportation below the root zone were measured in a paddy rice field and the data were simulated with the DRAINMOD-N model. For evaluating DRAINMOD-N software in a paddy rice field under surface drainage in Mazandaran, the ground water level and nitrate transportation were measured during four months (June, July, August and September) in 2008. The DRAINMOD-N model was calibrated by adjusting nitrification and denitrification rate constants to reach the best fit between measured and predicted data. Results indicate that predicted ground water level and nitrate concentration by model were significant at one percent level. The statistical comparison was done by model efficiency (EF) 0.84 for estimation of ground water level and 0.97 for estimation of nitrate concentration, respectively. The DRAINMOD-N model can be used as a tool to manage environmental pollution of nitrate in paddy rice fields.
A. Khanamani, E. Dodangeh, F. Soleymani , H. Karimzadeh, S. Soltani,
Volume 18, Issue 67 (6-2014)
Abstract
Underground water resources considered as a major source of fresh water. Increasing need to water in Iran, causing to
immensely utilization and ground water balance disorder, so that state of ground water in many of area is negative.The
purpose of this study is to investigate the trend of changes in some of the characteristics of groundwater during the
period 1374 to 1387 is Segzi plain. For this purpose, data gathered from the Organization of regional water and
homogenous test with Tom test (Run-test) at 95% confidence level was performed on the data. The independence of
data evaluated by time series auto correlated functions (ACF), to do this, the amount of auto correlated data computed
in different time delays and finally Mann- Kendall test used to evaluate the trend of time series properties in
groundwater. The results of Run-Test showed that all of used series in this study were homogenous (P value< 0.05).
The result of trend analysis test for region’s wells showed a significant increase in chlorine in underground water
resources (P value< 0.05). Calcium has an increasing Trend too about 3 units. Results also showed that all used series in
this study are random and Mann- Kendall trend analysis test can be an appropriate for trend evaluating in data series. As
regard to irregular utilization of underground water resources by increasing depth of water level, amount of different
salts such as chlorine and sodium increased, that causing to surface source degradation like soil and plant cover in
agricultural area.
S. M. Seyedan, R. Bahramloo,
Volume 22, Issue 4 (3-2019)
Abstract
In recent years, with the excessive use of underground water resources in the Malayer Plain, the water level has dropped sharply and underground water resources, which serve as the main source of water supply for the agricultural sector and drinking, the city is facing a serious risk. Because of the relevance of each of the fields with other agricultural fields around, this study was done to show the potential effect of this problem on the welfare. So, in this study, the special econometric method was employed. The purpose of this study was to analyze the welfare of farmers and how it is affected by the exploitation of underground water resources. For this purpose, by using social welfare function, the effect of change in the value of groundwater level of social welfare producers was addressed. The necessary information was collected from 119 questionnaires carried out in 2015 .Moran's I statistics showed that the results of special regression method were better than those of Ols. The results of this study indicates a decline in the welfare loss of groundwater level and the continuation of the harvest of underground water resources would lead to a reduction in access to water and reduced production. The rate of change in return for the welfare of the reduction of every meter of underground water level to cultivate wheat and potatoes was 6983 and 7634 million Rials, respectively.
M. M. Matinzadeh, J. Abedi Koupai, A. Sadeghi-Lari, H. Nozari, M. Shayannejad,
Volume 23, Issue 3 (12-2019)
Abstract
Selection of drainage equation with acceptable accuracy has always been a challenge for designers to design subsurface drainage systems. In this research, seven steady state drainage equations were used for predicting daily and cumulative drainage rate on a farmland of sugarcane in Imam agro-industrial Company. These drainage equation included Hooghoudt, Ernst, Kirkham and Dagan that have been developed in the past and Mishra and Singh, Henine and Yousfi et al that recently developed. The statistical indices consist of P-value, RMSE, R2 and Percentage Error of estimating cumulative drainage rate were calculated for Hooghoudt equation 0.9501, 1.49 (mm/day), 0.80 and -0.19%, respectively. For Ernst equation 0.0001, 2.46 (mm/day), 0.34 and 16.98%, respectively. The result of performance of drainage equations revealed that Hooghoudt and Ernst equation were as the equations with the highest and lowest accuracy in predicting drainage rate, respectively. Also from the newly developed equations, the Yousfi et al equation was found with relatively well accuracy to predict the drainage rate. This equation was placed in second rank after Hooghoudt equation and other equations showed poor performance. Thus, with selection of the appropriate drainage rate, the Hooghoudt equation is suggested for designing of drain spacing in medium to heavy textured soils such as sugarcane agro-industrial.
Sh. Nasiri, Hossein Ansari, A.n. Ziaei,
Volume 26, Issue 1 (5-2022)
Abstract
Hydrological models are useful tools in water resources planning, but some of them do not have satisfactory performance on a regional scale. Hydrological models are appropriate for a specific spatial scale and the lack of input data is a limiting factor in the modeling. One way to overcome this limitation is by using a flexible comprehensive model in different watersheds. Since surface and ground water have dynamic interaction in environmental ecosystems and form a combined water resources system so, the application of two general methods including fully integrated and coupled regions has been evaluated in this research. An investigation of these methods showed that the major focus in most studies is on increasing the accuracy of recharge and evapotranspiration rates in simulation. The results showed that the simultaneous use of SWAT and MODFLOW models to understand the hydrological conditions in a region has been able to cover the defects associated with the semi-distributional and distributive constraints of two models, simulating the surface-groundwater and the interaction between the aquifer and river. This method can provide useful information about the water balance of the basin and help to plan water resources more accurately
