• Estimation of Water Retention Characteristics Using Lognormal Distribution Model
  • Sang Il Hwang;
  • Korea Environment Institute;
  • 로그분포모형을 이용한 토양수분특성 추정
Abstract
Hwang and Powers (2003) developed a simple model for estimating water retention characteristic (WRC) directly from particle-size distribution (PSD) data, by applying a lognormal distribution law to both PSD and pore-size distribution. The objective of this work was to determine if the performance of the model developed by Hwang and Powers (2003) would be affected by soil texture. The results of this research proved that the performance of the model was indeed affected by soil texture. In particular, its performance diminished with increases in the fine particle fractions. Also, the nonlinear model, which assumes a nonlinear relation between particle-size and pore-size, performed better than the linear model, regardless of soil texture classes.

황과 Powers(2003)는 입도분포와 공극크기분포에 로그분포함수를 적용하여, 입도분포로부터 토양수분특성을 직접 추정하는 간단한 모형을 개발하였다. 본 연구의 목적은 황과 Powers(2003)가 개발한 모형의 추정능력이 토성에 의해 영향을 받는가를 밝히는 것이다. 연구결과, 모형은 토성에 의해 영향을 받았고, 특히 토양내 세립질 분율이 커질수록 모형의 추정능력은 감소하였다. 또한 입도와 공극크기사이의 관계를 비선형으로 가정한 비선형모형이 선형모형보다 토성에 관계없이 그 추정능력이 크게 나타났다.

Keywords: Water retention characteristics;Particle-size distribution;Lognormal distribution model;Soil texture;

Keywords: 토양수분특성;입도분포;로그분포모형;토성;

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This Article

  • 2003; 8(4): 21-26

    Published on Dec 1, 2003