Hamid reza Matin far; Kazem Alavi panah; Ammar Rafiei Emam
Volume 16, Issue 4 , January 2010, , Pages 560-573
Abstract
One of the apparent characteristics of soil is color which shows high correlation with soil characteristics and spectral reflectance. Soil color is identified using visual comparison of sample and colored chips of Munsell color charts .In arid regions due to the prolonged sunny days, low soil moisture, ...
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One of the apparent characteristics of soil is color which shows high correlation with soil characteristics and spectral reflectance. Soil color is identified using visual comparison of sample and colored chips of Munsell color charts .In arid regions due to the prolonged sunny days, low soil moisture, sparse vegetation cover and close relation between land units and soils, there is an ideal condition for application of remote sensing data especially for study of relation between satellite data and color of surface features. The soil color and the most effective factors on color and spectral reflectance of soil are explained in brief. Color composite images produced from TM7, TM4 and TM2 as red, green and blue respectively used in order to choose sample sites. The 20 sample sites were chosen based on resample 3×3 pixels (90×90 m). In each site, the soil surface conditions and the munsell color of the soil surface were investigated in the field. Some physico-chemical properties of soil samples were also determined in the laboratory. The results of this study indicates that munsell notation of hue, value and Chroma are significantly correlated to the visible bands of Landsat (TM) data. From this study it may be concluded that visible reflectance of Landsat can be used to estimate soil color, if very precise result is not expected .More investigation are necessary in order to improve the obtained results.
Tahereh Ensafi Moghadam; Amar Rafiei Emam
Volume 16, Issue 2 , December 2009, , Pages 274-292
Abstract
The present study firstly sets out the procedure for the generation of climatic files for localities with climatic records and secondly, The process of obtaining maps of the climatic zones for all of the localities in the Salt Lake Basin of Iran. For the generation of the climatic records such as rainfall ...
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The present study firstly sets out the procedure for the generation of climatic files for localities with climatic records and secondly, The process of obtaining maps of the climatic zones for all of the localities in the Salt Lake Basin of Iran. For the generation of the climatic records such as rainfall periods and intensity, provided by the 34 climatology stations for a total of 44 years data from (1957-2000), was used as a source of information. These data was then subjected to a statistical analysis, using SPI method for the calculation of the frequency, intensity and duration of drought process. Finally for the mapping drought zoning in all localities of the Salt Lake Basin for the long term period, the Inverse Distance Weighted Method(IDV) was used in the Arc view software environment. The results showed that the study area is very sensitive to climatic drought.
Daruosh Ghorbanian; Sudabeh korouri; Parvin Salehi; Amar Rafiei Emam; Mohammad Mousavi
Volume 15, Issue 4 , January 2009, , Pages 525-539
Abstract
This project was done as a part of ecological and phonological studies of Haloxylon sp. This study was done in artificial habitat (Mohsenabad in Garmsar) and natural habitat (Chahjam in Shahrood) of Haloxylon sp. General information about condition of Haloxylon sp. habitats was gathered. Haloxylon ...
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This project was done as a part of ecological and phonological studies of Haloxylon sp. This study was done in artificial habitat (Mohsenabad in Garmsar) and natural habitat (Chahjam in Shahrood) of Haloxylon sp. General information about condition of Haloxylon sp. habitats was gathered. Haloxylon stands were examined from different points including viability of seeds, dry matter in green, yellow and green- yellow stands. Phonological studies were done. In addition, soil physical and chemical properties were determined. Results indicated the direct and significant effect of precipitation and temperature on growth of Haloxylon sp. The other important factors were insufficient amount of major elements, unsuitable texture, the low distance between stands that caused strong competition between trees to get nutrients. The presence of rare green stands indicated their genetical resistance. It seems that the origin of these stands are form central desert region of Iran.
Ammar Rafiei Emam; Kazem Alavi panah
Volume 13, Issue 1 , February 2006, , Pages 1-9
Abstract
Remote sensing plays a considerable role on detection of natural resources features by its multi spectral means. Three decades works of remote sensing scientists have resulted in presentation of several vegetation indices, for soil how ever there are not many examples. TM spectral ratioing have been ...
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Remote sensing plays a considerable role on detection of natural resources features by its multi spectral means. Three decades works of remote sensing scientists have resulted in presentation of several vegetation indices, for soil how ever there are not many examples. TM spectral ratioing have been employed in this study to overcome problem of detection of soil variation. To reach the point spectral ratioing of TM (18 May 1998) was used. Data used in this study were: a) 3 first principle component, b) spectral ratioing of reflectance bands, c) spectral ratioing of Thermal band and d) original bands of TM. Results show that distinction of different soil in possible by PC3 on the basis of soil moisture variation. So, more researches in various regions for more studies in this subject are advised.