Mangrove wetlands can reduce heavy metal pollution by trapping heavy metals. In this study, the concentration, transport and bioaccumulation of Cr, Cd, Cu, Zn and Pb in the sediments and different parts of Aegiceras corniculatum at four different sites in the Qinzhou Bay in southwestern China were investigated. The results showed that although the potential ecological risk of all five heavy metals was slight, the concentration of Cr was at a moderate pollution level due to the emissions of industries and aquaculture waste water. Core sediment records indicated that the concentrations of heavy metals at the depth of 0–20 cm were relatively high, showing an increasing trend of heavy metals over the past 20–30 years. Cr, Cu, Pb and Cd accumulated mainly in the roots of A. corniculatum, while Zn accumulated mainly in the stems. Aegiceras corniculatum showed the strongest transport capacity for Zn and Cu and the strongest bioaccumulation ability for Cd. Compared with other mangrove communities, A. corniculatum can be chosen as a restoration species in tropical and subtropical coastal zones polluted by Zn, Cu and Cd.

Centropages tenuiremis is a species with a wide distribution range in disturbed coastal waters. However, due to a lack of dietary information, it remains unclear as to how they maintain such dominance in fluctuating conditions. In this study, C. tenuiremis was collected from the Daya Bay Nuclear Power Plant both in inlet and outfall regions at 06:00, 12:00 and 18:00 on April 27, 2011 and their in situ diet was analyzed using a PCR protocol targeting 18S ribosomal genes. Thirty-four species of prey organisms were identified totally, including Dinophyta, Baciliariophyta, Viridiplantae, Rhizaria, Apicomplexa, Chordata, Mollusca, Arthropoda and Fungi, indicating an obvious omnivorous feeding habit of C. tenuiremis. Centropages tenuiremis obviously exhibited spatial and temporal variations in diet composition. More plant prey (land plants and phytoplankton) were consumed in the morning (~50%), while more animal prey (metazoans and protozoans) were ingested at midday and night (60%–70%). Furthermore, a more diverse diet was detected in the outfall region (10–11 taxa), where the temperatures were relatively higher and more fluctuating, than in the control region (5–10 taxa). This finding indicated that C. tenuiremis could potentially expand its food spectrum under stressful condition. Specifically, C. tenuiremis exhibited phytoplankton preference (58.62%–67.64%) in the outfall region with a lower omnivory index (0.27–0.35) than in the control region (0.51–0.95). However, phytoplankton density was lower than that in the control region, suggesting a possible herbivorous tendency of C. tenuiremis under elevated temperatures to balance the energy acquirement and feeding effort. The flexible food choices of C. tenuiremis observed here could effectively buffer environmental fluctuations and might be an important survival strategy in coastal ecosystems.

²¹⁰Po and ²¹⁰Pb are increasingly used to constrain particle dynamics in the open oceans, however they are less used in coastal waters. Here, distributions and partitions of ²¹⁰Po and ²¹⁰Pb were examined in the Taiwan Strait, as well as their application to quantify particle sinking. Activity concentrations of dissolved ²¹⁰Po and ²¹⁰Pb (<0.6 μm) ranged from 1.21 to 7.63 dpm/(100 L) and from 1.07 to 6.33 dpm/(100 L), respectively. Activity concentrations of particulate ²¹⁰Po and ²¹⁰Pb varied from 1.96 to 36.74 dpm/(100 L) and from 3.11 to 38.06 dpm/(100 L). Overall, particulate ²¹⁰Po and ²¹⁰Pb accounted for the majority of the bulk ²¹⁰Po and ²¹⁰Pb. ²¹⁰Po either in dissolved or particulate phases showed similar spatial patterns to ²¹⁰Pb, indicating similar mechanisms for controlling the distributions of ²¹⁰Po and ²¹⁰Pb in the Taiwan Strait. The different fractionation coefficients indicated that particles in the Zhemin Coastal Current (ZCC) inclined to absorb ²¹⁰Po prior to ²¹⁰Pb while they showed an opposite effect in the Taiwan Warm Current (TWC). Based on the disequilibria between ²¹⁰Po and ²¹⁰Pb, the sinking fluxes of total particulate matter (TPM) were estimated to range from –0.22 to 3.84 g/(m²·d), showing an overall comparable spatial distribution to previous reported sediment accumulation rates. However, our sinking fluxes were lower than the sedimentation rates, indicating a sediment resuspension in winter and horizontal transport of particulate matter from the Taiwan Strait to the East China Sea.

To explore the spatial pattern of macrobenthic communities and their response to environmental factors in the Prydz Bay, samples were collected using a 0.25-m² box corer at 10 stations from November 2012 to April 2013. A total of 50 species of macrobenthos belonging to 8 phyla and 33 families were identified, of which polychaetes (e.g., Maldane sarsi) and sponges (e.g., Halichondria sp. and Leucosolenia sp.) were the most prominent groups. The macrobenthos in study area were categorized into five functional groups based on the feeding type, and the detritivorous group represented by polychaetes showed the highest average abundance, while the planktophagous group represented by sponges showed the highest average biomass. Macrobenthos abundance (0–592 ind./m²) and biomass (0–1 155.5 g/m²) in the Prydz Bay were relatively lower than those of other Antarctic shelf soft-bottom waters, although the compositions of the dominant species and functional feeding groups were similar. The results of the Spearman rank correlation analysis indicated that the average biomass of the macrobenthos and the biomass of the planktophagous group in the study area were negatively correlated with the water depth, sediment grain size and silt percentage. However, these variables were clearly not strong determinants of macrobenthos assemblage structure. Many factors not measured in the study, e.g., sediment organic matter and iceberg interference, have probably influenced the spatial distribution of macrobenthic community structure in the Prydz Bay.

We used satellite altimetry data to investigate the Kuroshio Current because of the higher resolution and wider range of observations. In previous studies, satellite absolute geostrophic velocities were used to study the spatio-temporal variability of the sea surface velocity field along the current, and extraction methods were employed to detect the Kuroshio axes and paths. However, sea surface absolute geostrophic velocity estimated from absolute dynamic topography should be regarded as the geostrophic component of the actual surface velocity, which cannot represent a sea surface current accurately. In this study, mathematical verification between the climatic absolute geostrophic and bin-averaged drifting buoy velocity was established and then adopted to correct the satellite absolute geostrophic velocities. There were some differences in the characteristics between satellite geostrophic and drifting buoy velocities. As a result, the corrected satellite absolute geostrophic velocities were used to detect the Kuroshio axis and path based on a principal-component detection scheme. The results showed that the detection of the Kuroshio axes and paths from corrected absolute geostrophic velocities performed better than those from satellite absolute geostrophic velocities and surface current estimations. The corrected satellite absolute geostrophic velocity may therefore contribute to more precise day-to-day detection of the Kuroshio Current axis and path.

An explicit one-dimensional model based on the shallow water equations (SWEs) was established in this work to simulate tsunami wave propagation on a vegetated beach. This model adopted the finite-volume method (FVM) for maintaining the mass balance of these equations. The resistance force caused by vegetation was taken into account as a source term in the momentum equation. The Harten–Lax–van Leer (HLL) approximate Riemann solver was applied to evaluate the interface fluxes for tracing the wet/dry transition boundary. This proposed model was used to simulate solitary wave run-up and long-periodic wave propagation on a sloping beach. The calibration process suitably compared the calculated results with the measured data. The tsunami waves were also simulated to discuss the water depth, tsunami force, as well as the current speed in absence of and in presence of forest domain. The results indicated that forest growth at the beach reduced wave energy loss caused by tsunamis. A series of sensitivity analyses were conducted with respect to variable parameters (such as vegetation densities, wave heights, wave periods, bed resistance, and beach slopes) to identify important influences on mitigating tsunami damage on coastal forest beach.

This study produced a statistical analysis of multicore eddy structures based on 23 years' altimetry data in global oceans. Multicore structures were identified using a threshold-free closed-contour algorithm of sea surface height, which was improved for this study in respect of certain technical details. Meanwhile a more accurate definition of eddy boundary was used to estimate eddy scale. Generally, multicore structures, which have two or more closed eddies of the same polarity within their boundaries, represent an important transitional stage in their lives during which the component eddies might experience splitting or merging. In comparison with global eddies, the lifetimes and propagation distances of multicore eddies were found to be much smaller because of their inherent structural instability. However, at the same latitude, the spatial scale of multicore eddies was found larger than that of single-core eddies, i.e., the eddy area could be at least twice as large. Multicore eddies were found to exhibit some features similar to global eddies. For example, multicore eddies tend to occur in the Antarctic Circumpolar Current, some western boundary currents, and mid-latitude regions around 25°N/S, the majority (70%) of eddies propagate westward while only 30% propagate eastward, and large-amplitude eddies are restricted mainly to reasonably confined regions of highly unstable currents.

We analyzed seafloor morphology and geophysical anomalies of the Southeast Indian Ridge (SEIR) to reveal the remarkable changes in magma supply along this intermediate fast-spreading ridge. We found systematic differences of the Australian-Antarctic Discordance (AAD) from adjacent ridge segments with the residual mantle Bouguer gravity anomaly (RMBA) being more positive, seafloor being deeper, morphology being more chaotic, M factors being smaller at the AAD. These systematic anomalies, as well as the observed Na_8.0 being greater and Fe_8.0 being smaller at AAD, suggest relatively starved magma supply and relatively thin crust within the AAD. Comparing to the adjacent ridges segments, the calculated average map-view M factors are relatively small for the AAD, where several Oceanic Core Complexes (OCCs) develop. Close to 30 OCCs were found to be distributed asymmetrically along the SEIR with 60% of OCCs at the northern flank. The OCCs are concentrated mainly in Segments B3 and B4 within the AAD at ~124°–126°E, as well as at the eastern end of Zone C at ~115°E. The relatively small map-view M factors within the AAD indicate stronger tectonism than the adjacent SEIR segments. The interaction between the westward migrating Pacific mantle and the relatively cold mantle beneath the AAD may have caused a reduction in magma supply, leading to the development of abundant OCCs.

In this study, the impact of oceanic processes on the sensitivity of transient climate change is investigated using two sets of coupled experiments with and without tidal forcing, which are termed Exp_Tide and Exp_Control, respectively. After introducing tidal forcing, the transient climate response (TCR) decreases from 2.32 K to 1.90 K, and the surface air temperature warming at high latitudes decreases by 29%. Large ocean heat uptake efficiency and heat storage can explain the low TCR in Exp_Tide. Approximately 21% more heat is stored in the ocean in Exp_Tide (1.10×10²⁴J) than in Exp_Control (0.91×10²⁴J). Most of the large ocean warming occurs in the upper 1 000 m between 60°S and 60°N, primarily in the Atlantic and Southern Oceans. This ocean warming is closely related to the Atlantic Meridional Overturning Circulation (AMOC). The initial transport at mid- and high latitudes and the decline in the AMOC observed in Exp_Tide are both larger than those observed in Exp_Control. The spatial structures of AMOC are also different with and without tidal forcing in present experiments. The AMOC in Exp_Tide has a large northward extension. We also investigated the relationship between AMOC and TCR suggested by previous studies using the present experiments.