Naghem Navabi; Mahnoosh Moghaddasi; Naser Gangi
Abstract
Drought is a natural phenomenon that occurs in almost all parts of the world. The effects of this crawling phenomenon are more pronounced in arid and semi-arid areas due to their annual rainfall. In contrast to traditional methods based on meteorological stations observations that focus more on weather ...
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Drought is a natural phenomenon that occurs in almost all parts of the world. The effects of this crawling phenomenon are more pronounced in arid and semi-arid areas due to their annual rainfall. In contrast to traditional methods based on meteorological stations observations that focus more on weather drought, the use of remote sensing and satellite imagery as a useful tool for monitoring agricultural drought has been considered. In the present study, the aim of comparing and assessing agricultural drought monitoring in Urmia Lake basin using VCI, VHI, TCI vegetation cover indices during the years 2000 to 2011 is using Madison. For this purpose, the NDVI index was first calculated from the images of Madis during June, July, August and September. Then, by comparing the mean of this index during these months, Shahrivar was selected with the maximum value as the month of the indicator. With regard to the minimum and maximum NDVI index in the months of September 2003 and 2008, VCI, VHI, TCI dash mapping maps were prepared. In order to evaluate the performance of agricultural drought indices, correlation coefficients were calculated for VCI, VHI and TCI profiles with SPI Meteorological Index. The results showed that the remote sensing index had a good accuracy in estimating the spatial and temporal dispersion of agricultural drought, so that the correlation coefficient between the VHI and SPI index was 0.86, which indicates that the index is consistent with the SPI meteorological index.
Saeideh Ansariyan; Mahnoosh Moghaddasi; Mojaba Moradi
Abstract
The success of the artificial recharge projects of aquifers need to recognition the appropriate points. The aim of this investigation is finding appropriate points for artificial recharge in “Kavir Meighan” basin in Markazi province. Because of that the Geographical Information System (GIS) ...
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The success of the artificial recharge projects of aquifers need to recognition the appropriate points. The aim of this investigation is finding appropriate points for artificial recharge in “Kavir Meighan” basin in Markazi province. Because of that the Geographical Information System (GIS) is used. In this investigation. the method“Analytic Hierarchy Process (AHP)” is used to find suitable points. By using the opinion of the experts, the necessary criterion to choose suitable points are: Water Quality, Water Depth, Slope, Land use, Geology, Soil texture and the position of wells, springs and Qanats. In AHP methods the raster layer of used criterion was prepared. Then by using double comparison and Expert choice software, the weight of the any layers was made. In this method the maps were put together by overlap methods. After that, inappropriate points those are too close to wells, springs and qanats, were showed. Finally, the potential map of artificial recharge zone was prepared. In AHP method the potential map contents 29 zones, the total area of them is 14,770,183 square meters.