간척지 논 토양의 염 농도가 메탄 배출에 미치는 영향

Abstract

BACKGROUND: Salt accumulation in coastal reclaimed soil can decrease plant growth and productivity, which could lead to considerable variation of methane(CH4) emission in a rice paddy. The objective of this study was to evaluate the effect of salt concentration on CH4 emission in a coastal reclaimed soil. METHODS AND RESULTS: The effect of salt concentration on CH4 emission and rice growth characteristics was studied by pot test, which packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Electrical conductivity(EC) of each treatment was controlled by 0.98, 2.25, 5.05 and 9.48 dS/m and CH4 emission was characterized a week interval by closed chamber method during rice cultivation. The CH4 emission rate was significantly decreased with increase of salt accumulation, but total CH4 flux in EC 5.50 dS/m treatment was lower than those of EC 9.48 dS/m treatment. It seems because of higher content of water soluble SO4 2- in EC 5.50 dS/m treatment than those of EC 9.48 dS/m treatment. Rice growth and grain yield were significantly decreased with increase of salt accumulation. Soil properties, especially EC and pH were negatively correlated with CH4 flux, while rice growth characteristics like plant height and tiller number show significantly positive correlation with CH4 flux. CONCLUSION(S): Conclusively, salt accumulation significantly decreased CH4 flux in a rice paddy, which could be useful information for evaluating CH4 flux in reclaimed area in Korea.