Journal of Irrigation and Water Engineering
Year:2015 | Volume:5 | Issue:18|Papers Count:10

Investigate variation of groundwater resource is very important in planning and sustainable management of water resource in each region. Quantitative and qualitative properties of ground water are changed in spatial and temporal scales; therefore it con not presumed fixed these properties. The goal of this study was investigate temporal and spatial variation ground water level in Kermanshah plain in annual, season and month in a 20 years period from 1991 to 2011 by using groundwater data of 61 piezometric wells. After was controlling of quality, accuracy and normality of data and Reconstruction of the statistical deficiencies, we used Kriging interpolation method for zoning variation of annual, season, and month, As well as Thiesson Polygon Method was used for variation of average height of piezometric level in Kermanshah plain. The diagram of height variation of piezometric level in each wells showed that preference of interpolation method compare to Thiesson Polygon Method. Assessment of results showed that average height of table groundwater during statistical period was felled 9.9 meter (0.49m in year), whereas fall variation in some of wells showed fall is upper 30m.

Temperature is one the most important parameters in climatology and hydrological investigations. The main purpose of this article is enhancing the resolution of the gridded annual temperature data of the NCEP/NCAR reanalysis dataset to a reasonable level. In this data base, temperature is available at the resolution of 2.5 degree. For regional studies in Iran, due to the diversity of topographical features, the precision of the available resolution is not enough. In this research, it is intended to replace a finer resolution of 1 degree by applying the interpolation methods embedded in the MATLAB. There are 4 different methods for interpolation in the MATLAB: Linear, Nearest Neighborhood, Spline and Natural Nearest Neighborhood. By applying these methods over the 30 second order watersheds across Iran, a network of 1*1 degree resolution was obtained from the 2.5*2.5 degree resolution. To examine the precision of the simulated data, the annual average temperature for each sub-watershed was calculated via the long term data of the 47 synoptic stations distributed unevenly across the country. Using RMSE, MBE, Nash-Sutcliffe and CRM statistics the Nearest Neighborhood and Spline methods was identified as the best methods for interpolation of the NCEP/NCAR reanalysis temperature data. The main result of this research is the generation of gridded temperature data for hydro-climatological studies, introducing a method for its updating and henceforth, omitting the labor of gathering, testing and using local data.

Water shortage in nature, especially in arid and semi-arid regions, often related to a decrease in water quality. This research is applied in loamy gravely field area which is located in 25 km away from city center of Mashhad in 1390-1390 and 1391-1392 cultivate years. The followed experimental design was randomized in split- split plot complete block in which four different levels of salinity (0.5, 5, 8 and 11 dS/m, are respectively in S1, S2, S3 and S4 levels) as the main plots, four irrigation levels as subplots (supply 125, 100, 80 and 50% water necessity, I1, I2, I3 and I4 Respectively) and two cultivars of canola (Hyola401 and RGS003) as the sub-sub plots in three places. Log - linear function of the entre salinity in I4 treatment yield higher is estimated grains application more than reality. Based on the results of quadratic functions and the higher order estimates are better than the other two functions. The coefficient of R2 determination values is shown that the rate of Hayola cultivars and RGS, quadratic function with R2=0.99 and R2=0.8 would be first level. In contrast, the minimum numbers of Hayola and RGS logarithmic and linear functions were respectively in the next ranking. The RMSE indices show that the total higher amount of Hayola cultivar and RGS are 12.5 and 8.17 percentage yield less (according to the CRM - positive) estimates of the real values while the quadratic function total amount of 11.7 and 6.4% performance for less (due to the positive CRM) are have been estimated the actual values. Thus, according to the occurrence comparison these indices for different functions and a final ranking is assigned to a quadratic function, this function is optimized as a function of the combined conditions of low salinity and irrigation Cultivars of Hayola and RGS which would be introduced in Mashhad.

Proper management of saline soils needs adequate information about the amount and salt distribution in the root zone. Irrigation of the factors that control the distribution of salt. This paper investigates salt distribution under two sources of dripper and bubbler. This study based on the evaporation of soil surface of a land without plant located at shahid chamran university, Ahwaz, Iran. Samples were taken from three distances 0, 20 and 40cm from the soil surface and 0-20, 20-40, 40-60 and 60-80 depths.The results showed that, the average salinity of bubbler were 12.75 dS/m that less than drippers with 13.64 salinity respectively. Among measured depth, the depth of 20–40 cm was known as the best working depths, the depth of 60-80 cm had the most salt with salinity of 15.76 dS/m. depth of 0-20 cm (with the average salinity of 12.53 dS/m includes more salinity than the depth of 20-40 with the average salinity of 11.48 dS/m. Soil salinity decreased by time pass and irrigation until the last irrigation, soil salinity under the dripper reached) with salinity of 3.62 dS/ m) to 1.15 and under the bubblersalinity of 3.99 dS/ m) to 1.14 of the initial amount.

In order to investigate the effects of organic and chemical fertilizers on yield and yield components of safflower (Carthamus tinctorius L.); Goldasht variety under water stress conditions, an experiment was conducted on research farm, Faculty of agriculture, Shahid Bahonar University of Kerman, in split plot with Randomize Block Design (RCBD); and 3 replications in each treatment. Water stress in three levels: 60 mm evaporation from evaporation pan (normal irrigation); 120 mm evaporation from evaporation pan (low water stress); 180 mm evaporation from evaporation pan (high water stress) in main plots and cow manure (15 t/ha); humic acid (80 kg/ha); chemical fertilizer (N=150 kg/ha, P=50 kg/ha, K=100 kg/ha), and control (no fertilizer) were in sub plots. The reasults showed that water stress caused decrease in leaves, Relative Water Content (RWC), yield, yield components and harvest index (HI); but increased chlorophyll meter numbers (SPAD). The effect of fertilizer was positively significant on all indices; except on 1000 seed weight. Cow manure increased seed yield significantly, and had positively significant effects on other indexes. It seems that organic fertilizer, specially cow manure in water stress condition, caused higher soil water content; and finally higher yield, compared to chemical fertilizer; and is better choice in water stress condition.

The spatial and temporal variation of wheat virtual water, as one of the strategic product in Sistan and Blouchestan Province, has been investigated. To this end, the 12 year weather data, yield, cultivated area and irrigation method were used. The 12 year average of the net wheat water use was 303 million cube meter from which 9.2 percentage was supplied by green water. Regardless of the irrigation efficiency, the net virtual water varied among 1.59 (Khash City) to 6.18 (Zabol City) meter cube per kilogram and its 12-year average was 3.42 meter cube per kilogram in the whole province. Considering the real water volume allocated to the wheat, the 12-year average of the imported and exported virtual water in the entire province was 1043 and 43.2 million cube meter, respectively, and Zahedan and Zehak were, respectively, the biggest importer and exporter of the virtual water. Results showed that decreasing the water loss by 10 percentages through improving irrigation efficiency would increase the sel-sufficiency in whaet production by 18.2% and decrease the dependency to virtual water import by 3.62 percentages due to 11.7 percentage decrease in wheat water use.

In rivers spatially ephemeral rivers, volume of water in downstream reduced due to transmission losses. Thus the modeling such process is important in water resources management and river engineering. In this study, using gene expression programming, transmission losses in zangmar River that is located in northwest Iran, based on observations input and output hydrographs in Mako and Poldasht stations has been calculated. After the introduction of various terminals and commen function in gene expression programming model, the output hydrograph in downstream stations were simulated. Statistical indices showed that the gene expression programming model predict output hydrograph acceptable so that the estimated output losses in comparison with the observed values is 7.4%.

Population growth, industrialization and the development of agricultural activities are the causes of increasing municipal and industrial wastewaters and irregular use of fertilizers and pesticides, and consequently the contamination of groundwater resources. Since the main problem with SINTACS models, applies expertise rating parameters to be used in it, in this study, the model using Analytical Hierarchy Process based on local hydrogeological conditions were indeed improvement. To achieve efficient models, the correlation coefficients between nitrate concentrations in the aquifer vulnerability index as an indicator of contamination were determined using Simple Linear Regression Analysis (SLRA). The results showed that the optimal model SINTACS than model the normal SINTACS is correlated with higher nitrate concentrations. Also, in order to assess risk Andimeshk aquifer pollution, land use parameters with the parameters used in the SINTACS model are overlaid, thus in turn specific aquifer vulnerability map was provided. Results from the map showed that the risk of aquifer contamination is not high.

Water is the soul of life and law is the organizer of life. Although water crisis is not a new concern, recently, it has been an objective problem. Unwritten law and canonical rule has an old root in country, but formal law which is a necessary for modern society is the young one esp. law of water which refers to 1930s. The three most effective laws in the field of water are: law aof “water and trends of its nationalization (1968)”, law of “justice distribution of water (1982) ”, and recently, law of "Determination for illegal wells (2010) ". The main objective of this research paper was to study and criticize the law of "Determination for illegal wells”. This research was a descriptive- correlational research using survey technique which was done during 2013 and 2014. Semi-structured questions were used for interview. Also questionnaire as research instrument included closed and open ended questions. Research population includes technical and legal affairs experts in Fars Regional Water Authority, official experts of law court in field of Water and also judges for water subjects. Data was extracted in quantitative and qualitative methods. For inferential statistics and drawing diagram, SPSS20 and Excel 2013 were used. According to findings, law of "Determination for illegal wells” is not environmentally friendly and cannot preserve groundwater and aquifer (6.4 out of 20), it is not a holistic law (6.7 out of 20), and it is practically a weak law (10.7 out of 20). Mann-Whitney U tests show that there are no significant differences between in viewpoint of experts about the preservative role of this law in regards of gender, education level and field of study. At the end, legal objections and executive challenges are discussed in details. Allocating this law for Non-banned areas, delivering a bill to the parliament for deleting or fundamental revising the law and also preparing the “holistic law for water”, are the suggestions.

Spur dike is one of the various hydraulic structures used in rivers, and are utilized in order to protect river banks, keeping the flow away from the walls, and directing them towards the main route. Due to flow digression, a turbulent circulation zone appears around the spur dike. Consequently, in order to prevent local scour, they use a wider, T-shaped nose for the spur dike. In this paper, a study on flow pattern around a 25 percent submerged T-shaped spur dike, located in a 45 degree position, in a 90 degree bend with rigid bed, and various relative radius of curvature 2, 3, 4, and 5, with a constant discharge of 25 lit/s has been conducted using Flow-3D software. Numerical results have been compared with experimental results, and they have been analyzed. The results indicate that with an increase in radius of curvature, the number of vortexes in cross sections near the wing of the spur dike, as well as lateral velocity of the flow increases, and the maximum lateral velocity is found upstream of the wing of the T-shaped spur dike. It was also observed that the less the relative radius of curvature is, the wider zone downstream of the spur dike has relative immobility of the flow.