Analysis of spatial variability of specific physical and hydraulic properties of soil on a catchment scale

آب و خاک

Article 36, Volume 22, Issue 2, May 2008   

Document Type: Research Article

DOI: 10.22067/jsw.v0i22.1042

Authors

H.R. Motaghian¹; A. Karimi^{* 2}; J. Mohammadi²

¹Shahrekord university

²College of Agriculture Shahrekord University

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 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