간척지 토양의 제염과정 중 전기전도도 분석 = Analysis of Electrical Conductivity during Desalinization of Reclaimed Tidal Lands

다국어 초록 (Multilingual Abstract)

This study was performed in order to produce the basic data for developing prediction techniques of desalinization to be applicable to reclaimed tidal lands at the beginning stage.
The desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage. The 5 soil samples used in this study were collected in 4 tidal land reclamation projects.
Regression equations were obtained in order to investigate the changes of electrical conductivity during the desalinization of reclaimed tidal lands and to estimate water requirements for desalinization.
The results obtained from this study were summarized as follows:
1. According to USDA Salinity Laboratory classification system of salt affected soils the reclaimed tidal land soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage.
2. With the increase of the water requirements for desalinization the electrical conductivity was decreased with high degree of correlationships and the desalinization effects were remakable in both the leaching method and the rinsing method.
3. In case of the leaching method the electrical conductivity had been reduced below the classification value of salt affected soils when the depth of water leached per unit depth of soil (Dwl/Ds) was 0.3 and the desalinization effects showed a tendency to be much the same in each treatment.
4. In the model experiments by the rinsing method, the electrical conductivity had been reduced below the classification value of salt affected soils when the depth of water applied per unit depth of soil (Dwa/Ds) was 3.0 in both permeable soils and impermeable soils. In the lysimeter experiments by the rinsing method, it was estimated that the electrical conductivity could be reduced below the classification value of salt affected soils when Dwa/Ds would be 3.5 in permeable soils and 4.5 in impermeable soils.
5. The leaching method has the merits of saving water requirements for desalinization and the convenience of desalinization works in permeable soils, but the demerit of a long period for desalinization. Also desalinization works would be next to impossible in impermeable soils through the leaching method.
On the other hand, the rinsing method has the adventage of a short period for desalinization regardless of permeability, but the desalinization of subsoil would be difficult and the water requirements for desalinization would require 10 times more than those of the leaching method.