We sampled the surface sediments of the East China Sea shelf (ECSS) in spring and autumn, 2014, and analyzed the biogenic element concentrations and stable carbon (δ13C) and nitrogen (δ15N) isotopic compositions to study the distribution and seasonal variations of sedimentary organic matter (OM). The average concentrations of TOC, TN and OP in autumn decreased obviously compared with those in spring. The increase of δ15N values in autumn indicated the priority utilization of 14N by bacterial decomposition activity. The values of δ13C were used to trace organic matter sources. The estimated percentages for terrestrial OM were in the range of 0–34.6%. They generally decreased seaward in nearshore areas, indicating the decrease of terrigenous influence. There was an obvious tongue-shaped region with relatively low percentages of terrestrial OM (<12%) in the northern part of the ECSS, which may be a reflection of the intrusion pathway of the outer seawater.

Sixty sediment samples from four sites in the Bijagós archipelago were characterized for fine fraction, loss on ignition, major, minor and trace elemental composition (Al, Fe, Ca, Mg, Ti, P, Zr, Mn, Cr, Sr, Ba, B, V, Li, Zn, Ni, Pb, As, Co, U, Cu, Cs and Cd), and the elements of the La–Lu series. Element concentrations were largely explained by the Al content and the proportion of fine fraction content, with the exception of Ca and Sr. Sediments showed enhanced Ti, U, Cr, As and Cd concentrations with respect to estimated upper crust values, most likely mirroring a regional signature. Rare earth elements were in deficit relatively to the North American Shale Composite (NASC), mainly in coarser material. No pronounced Ce-anomaly was observed, while Eu-anomalies were positive in most analyzed sediments.

Understanding the natural variability and its influence on the performance of marine biotic indices used for the health assessment of marine ecosystem is the prime concern. This study addresses the seasonal variability of univariate and multimetric indices by using macrobenthic data collected from three intertidal habitats for two years (July 2013–July 2015). The univariate indices viz., abundance, richness, Shannon index and ES (100) showed strong seasonal variability. For the multimetric indices, the seasonal variability was low and appeared site specific. W-statistics, AMBI and M-AMBI showed highest constancy whilst BENTIX and BOPA exhibited wide - ranging. A general tendency could be inferred as majority of indices showed improvement in benthic quality (poor - moderate and good - high) from turbulent monsoon to stable dry period. The results are discussed concerning possible consequences especially related to the benthic community and biotic indices in intertidal habitats under the influence of sewage discharge and monsoonal effects.

Copepods are the most abundant metazoans, forming a vital food chain link between the primary producers the phytoplankton and fish. This study presents baseline information on the concentration of ²¹⁰Po among calanoid copepods isolated from the Kuwait marine area. The concentration of ²¹⁰Po in six species of copepod, including Subeucalanus flemingeri, Parvocalanus crassirostis, Acartia pacifica, Calanopia elliptica, Acrocalanus gibber, and Euterpina acutifrons were 151.3–158.8 Bq kg⁻¹ wwt, 121.1–129.5 Bq kg⁻¹ wwt, 51.23–54.91 Bq kg⁻¹ wwt, 38.88–40.09 Bq kg⁻¹ wwt, 38.07–38.29 Bq kg⁻¹ wwt, and 33.46–36.50 Bq kg⁻¹ wwt, respectively.The ²¹⁰Po concentration in seawater shows a seasonal variation, with a higher concentration range of 0.58–0.70 mBq L⁻¹ during summer and autumn, while a lower concentration is found (0.30–0.38 mBq L⁻¹) during winter and spring. The concentration factor among the copepods varies between 8 ∗ 10⁴ and 5 ∗ 10⁵ that is an order of magnitude higher than the diatoms and dinoflagellates.

To fully understand the impact of oil exposure, it is important to understand sublethal effects like how increased thermoregulatory costs may affect survival and reproduction. However, it is difficult and time-consuming to measure these effects in wild animals. We present a novel use of a bioenergetics model, Niche Mapper™, to estimate thermoregulatory impacts of oiling, using data from captive Double-crested Cormorants (Phalacrocorax auritus) experimentally exposed to oil. Oiled cormorants had significant increases in surface body temperatures following exposure. Niche Mapper accurately predicted surface temperatures and metabolic rates for unoiled and oiled cormorants and predicted 13–18% increased daily energetic demands due to increased thermoregulatory costs of oiling, consistent with increased food consumption observed in experimentally oiled cormorants. We show that Niche Mapper can provide valuable insight into sublethal oiling effects by quantifying the extent to which thermoregulatory costs divert energy resources away from important life processes like maintenance, reproduction and migration.

When developing ozone control strategies, the empirical kinetic modeling approach curve cannot easily be applied to practical problems. On this basis, the ozone production efficiency (OPE) is proposed as an indicator to represent the effects of NOₓ on ozone. The research results of the OPE are reviewed and include the definition and calculation of OPE, observations and model simulations, several factors affecting the OPE, and the application of OPE. The measurements and applications of the OPE have improved and become widespread after decades of development. OPE is mostly used to measure regional atmospheric oxidation characteristics, which play an important role when developing ozone control strategies (especially in highly polluted areas). However, there have been few studies on the advancement of chemical mechanisms in the OPE in recent years. In addition, there is no detailed interpretation of the strong linear correlation between ozone and NOz. The results may be significant for improving simulation results and understanding the formation of ozone.

Water quality in Tolo Harbour and Channel (Tolo) has been improved since 1998 after the diversion of sewage effluent. However, it remains poorly understood how nutrient loading reduction has impacted the phytoplankton community. To evaluate this, we applied a Phytoplankton Community Index PI(mp) to the 23-year data (1991–2013) at inner (TM4) and outer (TM8) sites in Tolo, with the former being more eutrophic than the latter. The results show that 1) the phytoplankton community changed with time after sewage diversion; 2) “diatoms and dinoflagellates” were better indicators of nutrient impact than “autotrophic/mixotrophic and heterotrophic dinoflagellates”; 3) the rate of recovery differed between the two stations, but both reached a similar state at a similar time; 4) seasonality of the phytoplankton community showed greater disturbance in spring than in other seasons. Our findings indicate that the nutrient reduction in the Tolo resulted in a positive change in the phytoplankton community.

This study investigated occurrence of microplastic particles in digestive tracts of fishes from the Amazon River estuary. A total of 189 fish specimens representing 46 species from 22 families was sampled from bycatch of the shrimp fishery. Microplastic particles removed from fish gastrointestinal tracts were identified using Attenuated Total Reflectance – Fourier Transform Infrared (ATR-FTIR). In total, 228 microplastic particles were removed from gastrointestinal tracts of 26 specimens representing 14 species (30% of those examined). Microplastic particles were categorized as pellets (97.4%), sheets (1.3%), fragments (0.4%) and threads (0.9%), with size ranging from 0.38 to 4.16 mm. There was a positive correlation between fish standard length and number of particles found in gastrointestinal tracts. The main polymers identified by ATR-FTIR were polyamide, rayon and polyethylene. These findings provide the first evidence of microplastic contamination of biota from the Amazon estuary and northern coast of Brazil.

In-situ burning (ISB) is a remediation strategy that is used for managing oil spills. ISB generates heavy residues that can submerge and negatively impact benthic environments. To track the fate of toxic contaminants in ISB residues, a conservative hopane biomarker, such as C₃₀-αβ hopane, is often used. Furthermore, diagnostic ratios of various hopanes are used for source oil identification. Use of these biomarkers assume that during ISB the quantity of C₃₀-αβ hopane will be conserved, and the diagnostic ratios of various hopanes will be stable. The objective of this study is to test the validity of these two assumptions. We conducted laboratory-scale ISB experiments using a model oil prepared from commercial C₃₀-αβ hopane standard, and a reference crude oil. Laboratory data collected under controlled burning conditions show that C₃₀-αβ hopane will not be conserved; however, the diagnostic ratios of hopanes will still remain fairly stable.

This paper deals with marine plastic debris and its collection and recycling methods as one possible answer to the rising amount of plastic in marine environments. A novel approach is to use energy recovery, for example pyrolysis of marine plastic debris into high-energy products. Compared to other thermal processes, pyrolysis requires less technical effort and the end products can be stored or directly reused. In order to design such an onboard pyrolysis reactor, it is necessary to know more facts about the feedstock, especially the thermochemical behaviour and kinetic parameters. Therefore, a thermogravimetric analysis was carried out for three selected plastic sizes with a temperature range of 34–1000 °C. The results obtained from TGA showed the same curve shape for all samples: single stage degradation in the temperature region of 700–780 K with most of the total weight loss (95%). Small microplastics had an average activation energy of 320–325 kJ/mol.