M. Naderi; A. Karimi
Abstract
Abstract
In case the performance of irrigation and drainage systems could be monitored by using satellite data, which are taken in short intervals, the problems concerning these systems could be corrected. Roodasht region which is located in the lower part of the Zayanderood River Basin was considered ...
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Abstract
In case the performance of irrigation and drainage systems could be monitored by using satellite data, which are taken in short intervals, the problems concerning these systems could be corrected. Roodasht region which is located in the lower part of the Zayanderood River Basin was considered as a pilot plain. The basin is struggling with salinity and waterlogging which started by construction of the Zayanderood Dam and consequently, doubling the share of irrigation water of the area. For this purpose the satellite images of Landsat MSS and TM of 1976 through 1990 were used. Modifications was performed after field works, reviewing the available reports and maps from the area, and then, the satellite data were classified. Temporal analysis of the satellite images showed that by doubling the irrigation water share during 14 years, soils with severe and no salinity risk were decreased by 5 and 16%, respectively, while 20% was added to the land with moderately salinity risk. During this time the area of waterlogged lands has been doubled. The images of 1990 showed that new waterlogged lands were developed in the vicinity of the drainage and irrigation canals.
Key words: Satellite images, Landsat MSS and TM, Temporal analysis, salinity, Waterlogging
H.R. Motaghian; A. Karimi; J. Mohammadi
Abstract
Abstract
Analysis and interpreting spatial variability of soil hydraulic and physical properties on a catchment scale is important in hydrological modeling and decision making. This study was conducted to analyze and interpret spatial distribution of selected soil hydraulic and physical properties including ...
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Abstract
Analysis and interpreting spatial variability of soil hydraulic and physical properties on a catchment scale is important in hydrological modeling and decision making. This study was conducted to analyze and interpret spatial distribution of selected soil hydraulic and physical properties including clay, silt, and sand content, bulk density (BD), infiltration rate (IR) and saturated hydraulic conductivity (Ks) in Marghmalek watershed. In this research, 111 soil samples were collected in a regular spaced grid pattern of 1 km from 0-30 cm depth in order to determine the soil size distribution. In addition, at each sampling site undisturbed soil samples were obtained from the topsoil using cylinder method to determine soil bulk density and consequently the saturated hydraulic conductivity. Saturated hydraulic conductivity was determined using the falling head method. Infiltration tests were conducted on all 111 sample sites using double-ring infiltrometers. Maximum coefficient of variation (CV) was found for IR (72%) and Ks (67%). In contrast, the minimum CV value of 8% was found for BD. Statistical analysis illustrated that there was a significant difference (P
