5
Somayeh Sadr
Abstract
This research was conducted in order to investigate the quality of groundwater for agricultural use in the northern and central parts of Kerman Province. In this study, there were 534 water samples from 8 counties (Kerman, Zarand, Bam, Bardsir, Jiroft, Baft, Faryab, and Rafsanjan), which were collected ...
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This research was conducted in order to investigate the quality of groundwater for agricultural use in the northern and central parts of Kerman Province. In this study, there were 534 water samples from 8 counties (Kerman, Zarand, Bam, Bardsir, Jiroft, Baft, Faryab, and Rafsanjan), which were collected from different sources, and concentration of Na+, Ca+2, Mg+2, Cl-, SO4-2, and HCO3-2 was determined. Also, indicators such as Total Dissolved Solids (TDS), Sodium Absorption Ratio (SAR), Permeability Index (PI), Residual Sodium Bicarbonate (RSBC), Electrical Conductivity (EC), Salinity Potential (PS), Magnesium Hazard (MH), Water Hardness (TH), percentage of sodium soluble in water (SSP) were determined and evaluated. After determining the quality characteristics of water, the results were compared and interpreted with water standards for agriculture. AqQA software was used to draw graphs to investigate and compare water characteristics. Based on the results, more than 37% of the studied resources were classified as unsuitable (salinity above 2 dS/m) in terms of salinity. Zarand and Rafsanjan counties had unfavorable conditions in terms of groundwater quality indicators, with EC, SAR, PS, TH, SSP and MH in critical conditions in one or both counties, but, in terms of agricultural water standards, the other sites had good quality water. The combined type of underground water in all areas was Ca-Mg-SO4-Cl: while in the northern parts of the province, such as Rafsanjan, Zarand, Bardsir, as well as Bam and Kerman, the predominant anion of water was chlorine, in Faryab, Baft and Jiroft, the status of the predominant anions was slightly sulfate. In most of the counties, Na+>Mg+2>Ca+2 were the dominant anions of chlorine-waters, and little bicarbonate was observed. Also, the dominant water in all areas were Na-Cl and Mg-Cl . Therefore, it is necessary to manage water properly and plant crops suitable for the chemical conditions of waters.
5
Hooshang Ghamarnia; Sajad Ameri; Mahtab Nekookish
Abstract
A part of the plants' water needs can be met by shallow groundwater with desirable quality. In this research, contribution of shallow and saline groundwater to evapotranspiration of rosemary plant was studied in a completely randomized factorial design with three replications and using drainage lysimeters ...
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A part of the plants' water needs can be met by shallow groundwater with desirable quality. In this research, contribution of shallow and saline groundwater to evapotranspiration of rosemary plant was studied in a completely randomized factorial design with three replications and using drainage lysimeters with a diameter of 1.20 m, in 2017 and 2018. The applied treatments included groundwater with salinity levels of 1, 2 and 4 dS/m at a constant depth of 0.8 m. The results showed that the total water requirement of rosemary was 597 mm. From total water required by the plant, 312.6 mm (54%), 260.3 mm (44%), and 201.1 mm (34%) were supplied by shallow groundwater with qualities of 1, 2 and 4 dS/m, respectively. The daily groundwater contribution was 4.9, 3.9, and 3 mm by, respectively, treatments 1, 2, and 4 dS/m. The effects of groundwater salinity on the yield of rosemary plant parameters were significant at the level of 5%, which can be attributed to the tolerance of this plant to groundwater salinity. In addition, due to the rosemary plant use of groundwater with different qualities, some water from surface water can be saved and irrigated land can be expanded, with consequently higher crop production and more jobs for farmers.
5
ali mokhtaran; abdali naseri; Heidarali kashkuli
Abstract
In the new drainage conditions in the center and southwest of Khuzestan Province, by reducing the depth of drainage installation and controlled drainage, studying the dynamics of the mixing zone, understanding the specifications of this region, and its effect on the flow rate of drainage water and salinity ...
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In the new drainage conditions in the center and southwest of Khuzestan Province, by reducing the depth of drainage installation and controlled drainage, studying the dynamics of the mixing zone, understanding the specifications of this region, and its effect on the flow rate of drainage water and salinity is important. In this study, seven groups of piezometers, each consisting of 8 piezometers placed at different soil depths (0.8 to 5m) and at different distances from the drainage water collector were studied in two research farms, namely, field R9-11 Dabal Khazaei agro-industry (with an average drainage depth of 2 m and distances of 65 m) and field R8-7 in Salman Farsi agro-industry (with an average depth of 1.4 meters and 42 meters distances).Water level in piezometers, water salinity in different soil layers, and drainage water flow rate and salinity were monitored daily in three periods of heavy irrigation of sugarcane (March to October of 2013, 2014 and 2017). Results indicated that by starting a heavy irrigation, hydraulic head increased and hydraulic head variance between bottom layer (4 and 5 m) relative to the surface layers, established vertical flow and saline inflow upwards. Reducing the installation depth of drains up to 60 cm from in R9-11 compared to farm R8-7 and moving away from the collector up to 400 m in each farm, reduced the installation depth of drains up to 40 cm, and increased the hydraulic load by an average of 8-12 cm. The thickness of the mixing area was up to one meter and the reduction of the average salinity line in the mixing area was 8%. It was found that in addition to irrigation water salinity, drainage water salinity was affected by groundwater salinity and the difference in drainage depth, position of the impermeable layer, and the presence of sand lenses. By decreasing drainage depth, the drainage water discharge decreased sharply, such that the averag drainage water from each lateral in farm R9-11 was 10 mm/day, and in farm R8-7 it was 3.3 mm/day. The results showed that with increasing the thickness of the salt and fresh water mixing zone due to the optimal reduction of drainage depth, the volume of water consumed in each irrigation cycle decreased due to plant use of this zone, which can be an effective factor in conserving soil and water resources.
5
Alireza Karbasi; Toktam Mohtashami; Amin Alizadeh; Zahra Moghimi
Abstract
Agriculture in arid and semiarid areas is dependent on groundwater extraction. Utilization of groundwater resources in Zaveh-Torbath Haydarieh plain is more than the aquifer's renewable potential, therefore, these resources have a reservoir deficit. To this end, in this study, using the information obtained ...
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Agriculture in arid and semiarid areas is dependent on groundwater extraction. Utilization of groundwater resources in Zaveh-Torbath Haydarieh plain is more than the aquifer's renewable potential, therefore, these resources have a reservoir deficit. To this end, in this study, using the information obtained from interviews with farmers in this plain, who were selected through cluster sampling in the year 2015-2016, and the use of the Tobit Model and the two-stage method of Hackman, factors influencing the extraction of groundwater resources were studied. The results of the two-stage Hackman model showed that, in the first stage, the explanatory variables including the dominant cultivation and personal and share ownership of water wells had a positive final effect of 0.35, 0.43 and 0.41, respectively, while variables of well depth, type of water transfer channel, and low yielding crops had a negative effect on overdraft of groundwater resources. In the second stage, the results showed that farm-to-well distance, farmer's annual income, and type of the dominant cultivation had a positive and significant effect at 5 percent on overdraft. Accordingly, paying more attention to the technical factors effective in water management, as well as raising farmers' awareness of their participation in improving cropping pattern, is an effective step in reducing overdraft of groundwater resources.