Effects of a controlled freeze-thaw event on dissolved and colloidal soil organic matter
- 주제(키워드) Colloid , Dissolved organic matter , Fluorescence excitation-emission matrix (EEM) , Fourier transformation infrared spectroscopy (FT-IR) , Freeze-thaw , Principal component analysis (PCA)
- 등재 SCIE, SCOPUS
- 발행기관 Springer Verlag
- 발행년도 2016
- 총서유형 Journal
- URI http://www.dcollection.net/handler/ewha/000000139567
- 본문언어 영어
- Published As http://dx.doi.org/10.1007/s11356-016-7552-x
- 저작권 이화여자대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
This study investigated the effects of the freezing and thawing that accompany the warming process on the composition of the soil organic matter in the dissolved and colloidal fractions. Temperate soil samples were incubated in a refrigerator at 2 °C for 4 weeks and compared with those frozen at −20 °C in the second week followed by thawing at 2 °C to study a freeze-thaw effect with minimal effect from the thawing temperature. The freeze-thaw group was compared with those incubated at 25 °C in the last week to investigate a warming effect after thawing. Thawing at 2 °C after freezing at −20 °C increased the dissolved organic carbon (DOC), but decreased colloidal Ca. The subsequent warming condition greatly increased both DOC and colloidal Ca. The colloidal organic carbon (COC) and dissolved Ca showed rather subtle changes in response to the freeze-thaw and warming treatments compared to the changes in DOC and colloidal Ca. The fluorescence excitation-emission matrix (EEM) and Fourier transformation-infrared spectrometry (FT-IR) results showed that the freeze-thaw and warming treatments gave the opposite effects on the compositions of dissolved humic-like substances, polysaccharides or silicates, and aliphatic alcohols. A principal component analysis (PCA) with the DOC, fluorescence EEM, and FT-IR spectra produced two principal components that successfully distinguished the effects of the freeze-thaw and warming treatments. Due to the contrasting effects of the freeze-thaw and warming treatments, the overall effects of freeze-thaw events in nature on the dissolved and colloidal soil organic matter could vary depending on the thawing temperature. © 2016 Springer-Verlag Berlin Heidelberg
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