Hokkaido University · 지구·행성과학
유hei Yamashita 교수의 연구실은 해양 및 수문 환경에서의 용해성 유기물(DOM)과 그 상호작용을 중심으로 연구를 진행하고 있습니다. 특히, 형광 스펙트로스코피와 PARAFAC 분석을 활용해 DOM의 성분별 특성과 금속 이온(구리, mercury 등)과의 상호작용을 규명하며, 해양 유기물의 기원, 분포, 생물학적 생산 및 분해 과정을 이해하는 데 초점을 맞추고 있습니다. 연구는 주로 해안만, 강, 열대 강 유역 및 세계 해양을 대상으로 하여 수질 생물지구화학 순환의 이해를 심화하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Natural dissolved organic matter (DOM) is composed of a variety of organic compounds, which can interact with metals in aquatic environments. The interactions between DOM and two metals of environmental concern (Cu(II) and Hg(II)) were studied using fluorescence quenching titrations combined with excitation-emission matrix (EEM) spectra and parallel factor analysis (PARAFAC). This allowed characterizing the specific interactions between eight fluorescent components in DOM and two metals. Triplic
The distributions of fluorescent components in dissolved organic matter (DOM) from Ise Bay, Japan, were determined by excitation emission matrix (EEM) fluorescence spectroscopy combined with parallel factor analysis (PARAFAC). Three terrestrial humic‐like, one marine humic‐like, and three non‐humic‐like fluorescent components were identified by PARAFAC, and the environmental dynamics of individual fluorescent components in the bay area were evaluated. The observed linear relationships between sa
Tropical rivers are an important source of dissolved organic matter (DOM) to coastal oceans. However, temporal and spatial variability of DOM composition and thus its quality in such rivers, on landscape and basin scales, have not been well documented. In this study, we present data on the spatial distribution of DOM quantity and quality based on source, molecular weight, and composition using optical properties including excitation emission matrix fluorescence with parallel factor analysis. We
The horizontal and vertical distribution of marine humic‐like fluorophore, namely, chromophoric dissolved organic matter (CDOM) fluorescence, was surveyed in Ise Bay, Japan. The distribution patterns of salinity and marine humic‐like fluorescence intensity suggested that riverine humic‐like fluorophore conservatively distributed along with fresh‐sea water mixing in surface water at Ise Bay. However, analysis of mixing behavior of riverine CDOM implied that the 25.1 ± 10.6% in average of bulk mar
Abstract. Chromophoric dissolved organic matter (CDOM) ubiquitously occurs in marine environments and plays a significant role in the marine biogeochemical cycles. Basin scale distributions of CDOM have recently been surveyed in the global ocean and indicate that quantity and quality of oceanic CDOM are mainly controlled by in situ production and photobleaching. However, factors controlling the spectral parameters of CDOM in the UV region, i.e., spectral slope of CDOM determined at 275–295 nm (S
