Catchment-scale spatial variability analysis of soil hydro-physical properties in a semi-arid region of Iran

نویسندگان

1 M.Sc. student, Shahrekord University, Shahrekord, Iran

2 Associate professor, Shahrekord University, Shahrekord, Iran

3 Assistant professor, Shahrekord University, Shahrekord, Iran

doi
10.22059/jdesert.2008.36299
چکیده

Soil hydrau-physical data are important for many hydrological modelings. They are the main variables controllingthe key processes such as water and chemicals movement and transport in the soil profiles. This study was conductedin order to analyze the spatial distribution of selected soil hydrau-physcial characteristics including infiltration rate(IR), saturated hydraulic conductivity (Ks), bulk density (BD), clay, silt, and sand content. The study area wassampled on a pseudo-regular sampling scheme with initial grid spacing of 1 km during June and July 2007.Maximum coefficient of variation (CV) was found for IR (72%) and Ks (67%). While, BD showed a minimum CV of9%. Statistical analyses illustrated that there is a significant difference (P<0.05) in the mean values of IR in twodifferent landforms, i.e., plateaus and alluvial plains. However, different land uses including rangelands and dryfarming revealed no significant differences in the mean values of measured IR. The contrasting results were obtainedfor Ks. Geostatistical analyses revealed that the spatially dependent stochastic component (structure) waspredominant over the nugget variance (noise). The developed and modeled variograms of each variable were used ingenerating kriged maps. As expected, these maps exploited spatial similarities among soil properties.