majid khazayi; Iman Saleh; reza bayat; Shokr allah Absallan
Abstract
The concept of water productivity is to produce the best and most products by spending the lower amount of water. in this study water productivity was investigated with field surveys, field measurements and remote sensing analysis. For this purpose, in the first stage, water resources condition of the ...
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The concept of water productivity is to produce the best and most products by spending the lower amount of water. in this study water productivity was investigated with field surveys, field measurements and remote sensing analysis. For this purpose, in the first stage, water resources condition of the Basht aquifer investigated. in the next step, the cultivated area of Basht aquifer was investigated using Sentinel-2 satellite images in Google Earth Engine. Then, the agricultural condition of the aquifer investigated through questionnaire by farmers and experts. In the next step, the water requirement of the current cultivation pattern was calculated by the Penman-Monteith method. Finally, by evaluating the products in terms of productivity indicators, the water productivity of different products was determined. Penman-Monteith method calculations indicated that the water requirements of the aquifer dominant crops, including Citrus fruits, wheat, barley, corn, rapeseed, watermelon, branches, legumes and alfalfa respectively were 9170, 5630, 4821, 7863, 5411, 9291, 20234, 5225, 14083 cubic meters per hectare, respectively. In total, the amount of water consumed by the agricultural products in aquifer Basht is 45 million cubic meters, that approximately equivalent to 1 cubic meter per square meter of the aquifer cultivation area and and this amount is much more than the aquifer agriculture programmable water (17 million cubic meters).
Nader Oveisi; Reza Jafarinia; Lobat Taghavi; Jamal Ghoddousi
Abstract
Preservation of river ecosystem depends on the quantity and quality of the river flow regime, and the construction of large dams causes quantitative and qualitative changes in downstream rivers, so it is necessary to pay attention to the quality of rivers in addition to the quantity of water needs. Therefore, ...
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Preservation of river ecosystem depends on the quantity and quality of the river flow regime, and the construction of large dams causes quantitative and qualitative changes in downstream rivers, so it is necessary to pay attention to the quality of rivers in addition to the quantity of water needs. Therefore, in this study, a 22 km long section of the river at the bottom of Taleghan Dam located in Alborz Province (103 km of Karaj City) was selected with the aim of determining the minimum flow quantitatively in accordance with aquatic biological standards. Based on this, the average annual and monthly flow of the river in four stations in the study period with an approximate distance of six km from each other was estimated. Since there is a relationship between river hydraulic parameters such as depth and flow velocity with the habitat of the target species (such as the index fish), the measured field value was calculated to determine the optimal habitat conditions. Also, in this study period, to compare the possible change in the concentration of pollutants, each of the water quality parameters with its standard concentration for salmon survival was used as an ecological indicator and it was found that among 17 physicochemical parameters of water quality, Sulfate parameter (SO4) and its concentration can be considered as the most appropriate indicator for determining the minimum environmental flow for red-spotted trout in the Taleghan River. SPSS-24 software and One Sample T Test method were used to determine the mean concentration comparison test with standard concentrations of water quality parameters for Salmon biology.
