Bahman Kavari; Yahya Esmaeilpour; Ali Akbar Mousavi; Ommolbanin Bazrafshan; Arashk Holisaz
Abstract
The main source of water in the Arsanjan plain is underground water, which has been exploited in the past with Aqueduct and now with numerous wells. For knowing about the quality conditions of these sources; multivariate statistical analysis and interpolation methods were used in three years with different ...
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The main source of water in the Arsanjan plain is underground water, which has been exploited in the past with Aqueduct and now with numerous wells. For knowing about the quality conditions of these sources; multivariate statistical analysis and interpolation methods were used in three years with different rainfall. Factor analysis determined the key indicators of underground water quality and mapping was done with interpolation methods. The maps were classified using the Jenks optimization method of classification and the area of each class in each year calculated. Based on the results of factor analysis, EC, TH and Sodium concentration were selected with factor loadings of 0.843, 0.889 and 0.991, respectively. The RBF interpolation method for the sodium parameter was suitable in all three years of the study. For parameters of EC and TH, RBF-MQ method and LIP method had the least error in 2014 and 2015. Mapping spatial changes of the three mentioned parameters showed that in 2015, when the rainfall was lower than the average, the area of the regions with low values decreased. Due to the quantity and quality of its changes, sodium concentration parameter has a good potential to be used as an indicator of changes of the quality of underground water in response to climatic or management factors. In general, it is suggested that in assessment of the groundwater quality of Arsanjan Plain, the proximity factor to Bakhtegan Salt Lake, in addition to factors related to climate and watershed, should be considered.
Behnaz Asefjah; Yahya Esmaeilpour; Ommolbanin bazrafshan; Hossein Zamani
Abstract
The past decade has seen a major revolution in vegetation monitoring using satellite imagery, resulting in quantitative indicators of vegetation with a professional processor in a web-based interactive development environment. In this study, using MOD13A1 and MOD13Q1 products of Modis sensor, the trend ...
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The past decade has seen a major revolution in vegetation monitoring using satellite imagery, resulting in quantitative indicators of vegetation with a professional processor in a web-based interactive development environment. In this study, using MOD13A1 and MOD13Q1 products of Modis sensor, the trend of temporal and spatial changes of NDVI and EVI indices in Fars province in a period of 16 days from 2000 to 2020 was coded and processed monthly in Google Earth engine system. The results of this study showed that the average index of NDVI index is from minimum 0.11 to maximum 0.495 and the average index of EVI index is 0.1. According to the results obtained in this survey, in all the years from 2000 to 2020 in January, NDVI and EVI values had the highest values compared to other months, so that in January 2019 and January 2020, the highest EVI values averaged 0.22 and the NDVI values Was estimated to be 0.18. The lowest monthly average values of both indices occurred between 2000 and 2005, which indicates that the vegetation has been severely degraded during these years. The results of spatial changes using EVI index showed that the level of vegetation in Fars province in different months varied from 10,000 square kilometers to 22,000 square kilometers and from the perspective of NDVI index from 15,000 square kilometers to 30,000 square kilometers.
Sayyed Alireza Hosseini; Hassan Khosravi; Hamid Gholami; Yahya Esmaeilpour; Artemi Cerda
Abstract
In this study, land use change trend in coastal areas of south of Iran, including Sistan Baluchestan, Hormozgan, Bushehr were studied during 31 years (1988-2019). Landsat satellite images including TM, ETM +, OLI were used for this purpose. The maximum likelihood method was also used to classify satellite ...
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In this study, land use change trend in coastal areas of south of Iran, including Sistan Baluchestan, Hormozgan, Bushehr were studied during 31 years (1988-2019). Landsat satellite images including TM, ETM +, OLI were used for this purpose. The maximum likelihood method was also used to classify satellite images. Vegetation indices (SAVI) and salinity index (SI1) were used to influence land use classes on land degradation and desertification. The results of land use change trend showed that Changes in land use classes of man-made areas and saline lands as the most dynamic land use classes followed an increasing trend of 2.72% and 1.14%, respectively. The results of multivariate regression analysis showed that three vegetation, saline and man-made variables, and four vegetation, saline, man-made and sandy areas explain 22.3% and 37.8% of the dependent variables of vegetation and salinity indices, respectively. Therefore, in more than 60% of changes, other environmental variables are affected. Hence, with respect to the results of land use area and regression analysis and the mean trend of SAVI and SI1 changes, where vegetation and SAVI classes show decreasing trend and saline land and SI1 classes have increasing trend, it can be concluded that land use changes is phenomena that changes ecosystem services with almost irreversible impacts. This will have nothing to do with disturbing the ecosystem balance and intensifying land degradation in coastal areas.
Mohammad Jafari; ِAli Tavili; Yahya Esmaeilpour; Hossein Azarnivand; Mohammad Zare Chahouki; Hamid Reza Asghari
Abstract
Abstract In this study the effects and costs of application of two kinds of super absorbent polymer on the establishment and surviving of seedlings was investigated. Experiments were done in the field and on two kind of soil with different salinity (EC: 4.5 and 8 dsm-1). The results showed: the establishment ...
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Abstract In this study the effects and costs of application of two kinds of super absorbent polymer on the establishment and surviving of seedlings was investigated. Experiments were done in the field and on two kind of soil with different salinity (EC: 4.5 and 8 dsm-1). The results showed: the establishment rate of seedling in control was about 40 percent. The percentage of seedling establishment in the hydrogel treatments significantly increased and statistically is equal to the optimal surviving of the seedling (80%). Soil salinity on seedling establishment in the same treatments did not produce significant differences. The results were compared with a similar project to determine the costs and benefits. Based on the results a 30 percent reduction in water usage per round and 33 to 50 percent reduction in the number of irrigation replicate were recorded. The costs in compare to the normal project varied from -2 to 29 percent respectively for treatment Herbosorb® 0.5% and Aquasorb 1%. The treatments Herbosorb® and Aquasorb with usage level of 0.5% caused about 2.5 percent for each one percent increasing in the cost. There is no significant increase in the percentage of seedling survival by using 1% super-absorbent compared to 0.5 percent.
