peyman madanchi; mahmod habibnejadroshan; kaka shahedi; karim soleymani; Ahmad Fatehi
Abstract
Abstract:At present, there are a variety of reliable and practical methods for measuring soil moisture from point to world scale. Recently, remarkable progress in remote sensing techniques has allowed the scientific community to accurate and repeatedly map soil moisture anywhere in the world. The above ...
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Abstract:At present, there are a variety of reliable and practical methods for measuring soil moisture from point to world scale. Recently, remarkable progress in remote sensing techniques has allowed the scientific community to accurate and repeatedly map soil moisture anywhere in the world. The above points out the need for this research. In this research, this is the hypothesis, Do MERRA-LAND remote sensing data have an acceptable accuracy in determining the soil moisture content of the baft watershed? To answer this question, After downloading the data and reading them, Pearson correlation method was used to validate the data between monthly average remote sensing data and monthly average precipitation of baft synoptic and Kiskan Rainfall stations measurement in 2009-2013. The results showed 99% confidence in the Kiskan station and 95% confidently at the baft station There is a high correlation between monthly average soil moisture content downloaded with average monthly rainfall, Then, to compare the mean of MERRA-LAND data from the Goddard earth science(GES DISC) As predicted data at the specified date and time and the percentage moisture content obtained from 14 sampling points from the soil surface and the root zone area in the baft basin, the same time and date was used as in-situ data. Mean comparison of T-pair method was performed in SPSS software for each sample. The results showed that due to the higher T calculated from the table T with a degree of freedom 13 compared to the moisture content of the surface area and the root area there is no significant difference with surface download data and root area with 99% confidence. And can be recommended to the executive department Instead of spending a lot of time and cost Use the percentage moisture content provided by this site to predict and monitoring agricultural drought.
Freidoon Soleimani; Aaollah Kavian; Karim Solaimani; Forod Sharifi; Kaka Shahedi
Abstract
The major issues that must be addressed in watersheds is correct estimating threshold from the rainfall events. According to the agricultural leveling land and irrigation and drainage network of study area is exposed to sourounding runoff destruction, so watershed management activities such as design ...
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The major issues that must be addressed in watersheds is correct estimating threshold from the rainfall events. According to the agricultural leveling land and irrigation and drainage network of study area is exposed to sourounding runoff destruction, so watershed management activities such as design of small-scale water structures, sediment control structures, implementing the management actions in vegetation, soil and land utilization is required to understand and estimate surface runoff threshold. The aim of this study was to determine the effect of soil conservation practices on runoff initiation time and runoff coefficient using rainfall simulator in the Arayez plain. For this purpose, a rain simulator with a metal plot that has a square meter area was used. The treatments consisted of natural soil (observed), polyacrylamide at two levels 3 and 6 grams per square meter (P3 and P6, respectively) and Parsian mulch (Pc) that were conducted in sandy clay loam and sandy loam soil with three replications. The rainfall intensities set up to be of 32 and 50 mm per hour in slopes 7.5 and 12.5 percent. For statistical comparison split split plot design was used. Least Significant Difference (LSD) method was used for comparison of means. Results indicated that the mean of runoff initiation time in observed treatment is higher than mulch treatments, it means which runoff begins later in observed treatment. Mulches of P6 and Pc have not significantly differences in runoff initiation time. Runoff initiation time in P3 mulch much earlier began than the other treatments. Also, results revealed that the mean of runoff coefficient in different treatments (observed, P3, P6 and Pc) have a significant differences, and belonged to separate group.
