Spatial-temporal impacts of invasive Spartina anglica on the rates and pathways of organic carbon mineralization and resulting C-Fe-S cycles in the intertidal wetland of the Han River Estuary, Yellow Sea.

To elucidate the spatial-temporal impact of invasive saltmarsh plant Spartina anglica on the biogeochemical processes in coastal wetlands, we investigated the rates and partitioning of organic carbon (C) mineralization in three representative benthic habitats: (1) vegetated sediments inhabited by invasive S. anglica (SA); vegetated sediments by indigenous Suaeda japonica; and (3) unvegetated mud flats. Microbial metabolic rates were greatly stimulated at the SA site during the active growing seasons of Spartina, indicating that a substantial amount of organic substrates was supplied from the high below-ground biomass of Spartina.

Impacts of the invasive Spartina anglica on C-S-Hg cycles and Hg(II) methylating microbial communities revealed by hgcA gene analysis in intertidal sediment of the Han River estuary, Yellow Sea.

We investigated the impact of invasive vegetation on mercury cycles, and identified microorganisms directly related to Hg(II) methylation using hgcA gene in vegetated mud flats (VMF) inhabited by native Suaeda japonica (SJ) and invasive Spartina anglica (SA), and unvegetated mud flats (UMF) in Ganghwa intertidal sediments. Sulfate reduction rate (SRR) and rate constants of Hg(II) methylation (K) and methyl-Hg demethylation (K) were consistently greater in VMF than in UMF, specifically 1.5, 2 and 11.

Distinct temporal dynamics of planktonic archaeal and bacterial assemblages in the bays of the Yellow Sea.

The Yellow Sea features unique characteristics due to strong tides and nutrient-enriched freshwater outflows from China and Korea. The coupling of archaeal and bacterial assemblages associated with environmental factors at two bay areas in the Yellow Sea was investigated. Temporal variations of the archaeal and bacterial assemblages were shown to be greater than the spatial variations based on an analysis of the 16S rRNA gene sequences.

Impacts of typhoon-induced heavy rainfalls and resultant freshwater runoff on the partitioning of organic carbon oxidation and nutrient dynamics in the intertidal sediments of the Han River estuary, Yellow Sea.

Occurrence of typhoons accompanied by heavy precipitation has increased for the past 40 years in northeast Asia. To elucidate the impact of three consecutive typhoon-induced heavy rainfall events and resultant freshwater runoff on the partitioning of organic carbon (C) oxidation and nutrient dynamics, we investigated the geochemical constituents, the rate of anaerobic C oxidation, sulfate reduction (SR), iron reduction (FeR) and P speciation in the intertidal mud flat of the Han River estuary, Yellow Sea. C oxidation by SR and FeR and their metabolic products (∑CO, NH, HS, Fe) decreased significantly (P < 0.

A large artificial dyke greatly alters partitioning of sulfate and iron reduction and resultant phosphorus dynamics in sediments of the Yeongsan River estuary, Yellow Sea.

We investigated sediment geochemistry, partitioning of organic carbon (C) oxidation by iron reduction (FeR) and sulfate reduction (SR), and benthic phosphorus (P) release, together with the P speciation in the sediments to elucidate the P dynamics in two contrasting sediments (i.e., estuarine vs.

Impacts of long-line aquaculture of Pacific oysters (Crassostrea gigas) on sulfate reduction and diffusive nutrient flux in the coastal sediments of Jinhae-Tongyeong, Korea.

We investigated the environmental impacts of long-line aquaculture of Pacific oysters (Crassostrea gigas) on sediment geochemistry and carbon oxidation by sulfate reduction and diffusive benthic nutrient flux in a coastal ecosystem in Korea. Inventories of the NH4(+) and HPO4(2-) at the farm site were 7.7-11.