Publications by authors named "Neung-Hwan Oh"

Approximately 64% of the Republic of Korea comprises mountainous areas, which as cold and high-altitude regions are gravely affected by climate change. Within the mountainous and the alpine-subalpine ecosystems, microbial communities play a pivotal role in biogeochemical cycling and partly regulate climate change through such cycles. We investigated the composition and function of microbial communities, with a focus on fungal communities, in Republic of Korea's second tallest mountain, Mt.

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Coastal sediments accumulate organic matter (OM) from diverse sources, including local anthropogenic pollution. Effective source tracking of sediment OM is crucial for pollution source management. This study compares fluorescence proxies and stable isotopic ratios as tracers for sediment OM in Gangu Port, Korea.

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Energy deprivation triggers various physiological, biochemical and molecular changes in plants under abiotic stress. We investigated the oxidative damages in the high altitude grown conifer Korean fir (Abies koreana) exposed to waterlogging stress. Our experimental results showed that waterlogging stress led to leaf chlorosis, 35 days after treatment.

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Atmospheric particulate matter (PM) can damage human health. Biogenic organic compounds emitted from trees may increase the concentration of PM via formation of secondary aerosols. Therefore, the role of biogenic emissions in PM formation and the sources of PM need to be investigated.

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Tracking the sources of organic carbon (OC) is critical not only for understanding riverine carbon dynamics but also for providing management options to improve water quality. We collected water samples from upland forest streams to the mainstream Geumho River (GHR) of South Korea, which included a variety of wastewater treatment plants (WWTP) effluents. We analyzed the concentrations, optical properties, and dual carbon isotope ratios of these samples to identify the sources of OC.

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Forest and agricultural land use affects the concentration and composition of dissolved organic carbon (DOC) in streams and rivers. To elucidate the impacts of forest and agricultural land use on stream DOC during storm events, we investigated DOC concentration ([DOC]), optical properties of dissolved organic matter (DOM), and ΔC-DOC in both forest- and agriculture-dominated headwater streams in South Korea in the summer of 2012. One forested and five agricultural streams were investigated.

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This review provides focused insights into the contamination status, sources, and ecological risks associated with multiple classes of antibiotics in surface water from the East and Southeast Asia based on publications over the period 2007 to 2020. Antibiotics are ubiquitous in surface water of these countries with concentrations ranging from <1 ng/L to hundreds μg/L and median values from 10 to 100 ng/L. Wider ranges and higher maximum concentrations of certain antibiotics were found in surface water of the East Asian countries like China and South Korea than in the Southeast Asian nations.

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Radiocarbon (C) analysis is a powerful tool for tracing carbon in the global carbon cycle. Precipitation is a component of the global carbon cycle through which dissolved organic carbon (DOC) enters terrestrial and aquatic ecosystems from the atmosphere. In previous studies, the ΔC of DOC in rain or snow was negative indicating an input of relatively old organic carbon including fossil fuels, with only a few positive values up to +108‰ showing the signal of recent photosynthesis.

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The water and dissolved inorganic carbon exported by rivers are important net fluxes that connect terrestrial and oceanic water and carbon reservoirs. For most rivers, the majority of dissolved inorganic carbon is in the form of bicarbonate. The riverine bicarbonate flux originates mainly from the dissolution of rock minerals by soil water carbon dioxide, a process called chemical weathering, which controls the buffering capacity and mineral content of receiving streams and rivers.

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