The composition of altered volcanic ash of the Late Ordovician Kinnekulle bed was studied in geological sections of the Baltic Paleobasin. The composition of altered ash varies with paleosea depth from northern Estonia to Lithuania. The ash bed in shallow shelf limestones contains an association of illite-smectite (I-S) and K-feldspar, with the K2O content ranging from 7.5 to 15.3%. The limestone in the transition zone between shallow- and deep-shelf environments contains I-S-dominated ash with K2O content from 6.0 to 7.5%. In the deep-shelf marlstone and shale, the volcanic ash bed consists of I-S and kaolinite with a K2O content ranging from 4.1 to 6.0%. This shows that authigenic silicates from volcanic ash were formed during the early sedimentary-diagenetic processes. The composition of the altered volcanic ash can be used as a paleoenvironmental indicator showing the pH of the seawater or porewater in sediments as well as the sedimentation rate.

Quantifying and managing the cumulative effects of human activities on coastal and marine environments is among the foremost challenges in enabling sustainable development in the twenty-first century. As the speed with which these environments are changing increases, there is greater impetus to resolve the evident problems facing governance systems responsible for managing cumulative impacts. Policymakers and regulators recognise the need to assess and manage cumulative effects, as evidenced by widespread legislation requiring cumulative effects assessment (CEA). Yet there is ample evidence that we are not turning the tide in terms of balancing good environmental health with increasing demands of already degraded coastal and marine spaces that are increasingly impacted by climate change. This paper reviews the current state of knowledge regarding scientific and practical advances in CEA, assesses whether these advances are being applied in decision-making and identifies where challenges to implementation exist. Priority research questions are formulated to accelerate the inclusion of effective CEA in marine and coastal planning and management.

The United Republic of Tanzania, also called Tanzania, is a country composed of Mainland Tanzania and the islands of Zanzibar. Tanzania's domestic laws promote sustainable development of the marine environment; however, since the beginning of the 21st century, the country has been importing large quantities of oil, resulting in an increased risk of vessel-source oil pollution damage. Through a comparative analysis, this article examines the laws addressing this issue in Mainland Tanzania and Zanzibar, the progress that has been made in the legal environment and the challenges that remain, and it discusses possible solutions and improvements. The article reveals that weak implementation of domestic laws for marine environment conservation, a lack of harmonization between domestic laws regarding this issue, and weak domestication of relevant ratified international conventions are among the challenges currently hindering the sustainability of Tanzania's marine environment.

This article considers the under-studied question of the interests that the international community may have in the protection of the marine environment within national jurisdiction. This question is addressed on the basis of a comprehensive analysis of the major documents that reveal the convictions of the international community, including UN General Assembly resolutions, major international treaties and the outcomes of multilateral conferences. The core argument is that, despite the dominance of the zonal jurisdictional regime in the law of the sea, the international community has, in fact, clearly and consistently demonstrated an interest in the protection of the marine environment within national jurisdiction. Although a finding of community interest does not affect the character of the coastal State's primary environmental protection obligations, it may have implications for the rights of third States to challenge a coastal State's failure to protect its own marine environment. Whether third States choose to exercise this right in practice remains to be seen; however, this article's findings should indicate to States that their actions and policies concerning the protection of the marine environment of their own maritime zones are a matter of concern to all States.

This article takes stock of the contribution of the International Tribunal for the Law of the Sea (ITLOS) to the development of international environmental law. It examines in this regard the jurisdiction of the tribunal and provides an overview of its environmental jurisprudence. It then assesses the potential role of ITLOS in relation to some marine environmental challenges ahead. In particular, it considers the possibility of a request for an advisory opinion on climate change, the settlement of disputes regarding deep seabed mining, and the potential role of the tribunal under a new legal instrument on the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction.

The concentration of radiocarbon (14C) differs between ocean and atmosphere. Radiocarbon determinations from samples which obtained their 14C in the marine environment therefore need a marine-specific calibration curve and cannot be calibrated directly against the atmospheric-based IntCal20 curve. This paper presents Marine20, an update to the internationally agreed marine radiocarbon age calibration curve that provides a non-polar global-average marine record of radiocarbon from 0–55 cal kBP and serves as a baseline for regional oceanic variation. Marine20 is intended for calibration of marine radiocarbon samples from non-polar regions; it is not suitable for calibration in polar regions where variability in sea ice extent, ocean upwelling and air-sea gas exchange may have caused larger changes to concentrations of marine radiocarbon. The Marine20 curve is based upon 500 simulations with an ocean/atmosphere/biosphere box-model of the global carbon cycle that has been forced by posterior realizations of our Northern Hemispheric atmospheric IntCal20 14C curve and reconstructed changes in CO2 obtained from ice core data. These forcings enable us to incorporate carbon cycle dynamics and temporal changes in the atmospheric 14C level. The box-model simulations of the global-average marine radiocarbon reservoir age are similar to those of a more complex three-dimensional ocean general circulation model. However, simplicity and speed of the box model allow us to use a Monte Carlo approach to rigorously propagate the uncertainty in both the historic concentration of atmospheric 14C and other key parameters of the carbon cycle through to our final Marine20 calibration curve. This robust propagation of uncertainty is fundamental to providing reliable precision for the radiocarbon age calibration of marine based samples. We make a first step towards deconvolving the contributions of different processes to the total uncertainty; discuss the main differences of Marine20 from the previous age calibration curve Marine13; and identify the limitations of our approach together with key areas for further work. The updated values for ΔR, the regional marine radiocarbon reservoir age corrections required to calibrate against Marine20, can be found at the data base http://calib.org/marine/.

An investigation was carried out on the bioavailability of kaolinite and the role it plays in remediating oil-polluted seawater, since kaolinite is known to enable hydrocarbon-degrading bacteria to grow well. Experimental results revealed that significant amounts of Al and Si dissolved from kaolinite were not observed ((P > 0.05) in comparison with a control sample which contained no kaolinite) in the aqueous phase during the ~24 day experimental period. Transmission electron microscope observations and energy-dispersive spectroscope data revealed that some altered kaolinite particles appeared, connected to intact kaolinite and bacterial cells. Bacterial cells were associated and encrusted with intact and/or altered kaolinite clay particles, where mixed (C, O, Na and Si)-precipitates of kaolinite clays were formed on the surface of hydrocarbon-degrading bacterial cells. However, the uptake of Si (from kaolinite) by bacterial cells appeared to be more prevalent than Al, and there were no significant changes in basal spacings of kaolinite due to these altered kaolinite particles. Separate studies showed that hydrocarbon-degrading bacteria have a high resistance to Si. Thus, the present data suggest that Si from kaolinite may facilitate hydrocarbon-degrading bacterial growth as shown in our previous study (Chaerun et al., 2005), and the C-O-Na-Si complexes on the surfaces of bacterial cell walls may be the stimulator for hydrocarbon-degrading bacterial growth in seawater contaminated with oil spill.

The ability of montmorillonite to mitigate the toxic effect of heavy oil from the Nakhodka oil spill, by growth of hydrocarbon-degrading bacteria and enable bioremediation was studied. Montmorillonite enhanced the bacterial growth significantly (P < 0.05) in the main treatment containing heavy oil+bacteria+montmorillonite (OBM), because the specific growth rate (μ) was greater than that in the biotic control treatment containing heavy oil+bacteria (OB). Significant amounts of Si and Al (major constituents of montmorillonite) were not released in the aqueous phase over the ∽24-day experiment (P > 0.05). Transmission electron microscopic observation showed that the hydrocarbon-degrading bacterial cells were covered and encrusted with montmorillonite particles. Scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS) also showed that the surrounding of the bacterial cells was frequently rich in Si but not in Al. Fourier transform infrared (FTIR) spectroscopy indicated that the heavy oil-bacterial cell-montmorillonite particle complex retained the composition of both water and heavy oil. X-ray powder diffractrometery (XRD) analysis revealed that heavy oil and heavy oil-bacteria did not change the basal spacing of montmorillonite over a period of 24 days. The enhancement of hydrocarbon-degrading bacterial growth is attributed to montmorillonite likely serving as both bacterial growth-supporting carrier and protective outer layer against high concentrations of heavy oil that inhibit growth. These results shed light on the interactions in oil-bacteria-clay complexes and could potentially be used in marine oil spill bioremediation.

Radioactive particulate matter (identified as hot particles) is present in the effluent discharged by the British Nuclear Fuels Ltd (BNFL) uranium reprocessing plant at Sellafield, Cumbria, UK. There is very little information on the abundance or chemical and physical forms of solid matter in the effluent; even less is known of the significance of particulate debris in relation to the uptake of radionuclides for non-occupationally exposed people as a result of transfer along marine foodchains. Some observations on the occurrence and abundance of hot particles in the vicinity of Sellafield are reported, with special reference to those that contain transuranic radionuclides (Pu,Am,Cm). Some of the uncertainties are discussed in an evaluation of the significance of hot particles, albeit aggregates of colloids for the smallest particles, and exposure to man from ionizing radiation. There is no evidence that hot particles derived from BNFL and subsequently dispersed into the marine environment represent a hazard to man. However, further studies are required in order to determine whether or not the pathways followed by the particles are significant, or different to those of other radionuclides through which the radiation exposure of man within this region of Cumbria is assessed.

A 9.24 m sediment core, GA-2, was collected on the coastal platform of Grande Valley, a relatively narrow and shallow fjord in Fildes Peninsula, King George Island, Antarctica. The sediment was formed between 6600 and 2000 cal. yr bp according to accelerator mass spectrometry (AMS) 14C dating of five bulk sediment samples. The comprehensive proxy indicators (grain size, loss on ignition at 550°C, magnetic susceptibility, elements) were analysed, and three separate depositional environments and an alternating climate change pattern were identified. Grande Valley experienced a warm marine environment between 6600 and 5800 cal. yr bp, a minor cooling between 5800 and 4800 cal. yr bp, the transition from cool to warm during 4800–4400 cal. yr bp, a mid-Holocene climatic optimum between 4400 and 2700 cal. yr bp, and the onset of the Neoglacial at 2700 cal. yr bp. This study reconstructed the environmental history of Grande Valley during the mid–late Holocene, provides the missing marine record of historical climate for the western coast of Fildes Peninsula and lays the foundation for further study of the climate and environment changes therein. Our finding that the sea level was c. 12 m a.m.s.l. at 2000 cal. yr bp allows for detailed reconstruction of Holocene sea level variations.

The marine Eemian (marine oxygen-isotope substage 5e: MIS 5e) is represented by shallow-water deposits in southern and western Denmark, while relatively deep-water environments occurred to the north and north-east, where complete interglacial successions seem to be present. We present an overview of the marine Eemian deposits in Denmark, and discuss in more detail indications of climate variability, both for the late Saalian and within the Eemian.

The activity concentration of 137Cs, 131I, 65Zn, 60Co, 58Co, 54Mn, and 40K were determined in samples of brown seaweed (Fucus) and some other marine plants using low background high-resolution gamma-spectrometry. The algae were mainly sampled in the bay just north of the Barsebäck NPP (55.4 N, 12.6 E) in the south of Sweden to study the contamination levels in the nearest shallow waters. One aim of the study was to investigate whether the levels were high enough to expect environmental effects. Some samples were also taken at longer distances up to 130 km from the Barsebäck NPP. Measurable levels of the neutron activation products 65Zn (up to 17 Bq/kg dw), 60Co (100–600 Bq/kg dw), 58Co (1–160 Bq/kg dw) and 54Mn (12–90 Bq/kg dw) were found in the algae samples within a distance of 5 km from the plant. The decrease in activity concentration with distance from the plant could be described by a power function with an exponent ranging from 1.4 to 2.4.This was in fair agreement with the value for a true two-dimensional dispersion model. The present-day concentrations were found to be considerably lower than in earlier studies made in the late 1970s, especially for 65Zn and 58Co. The activity concentration of gamma emitting radionuclides in Fucus vesiculosus from the bay just north of Barsebäck in the period 2002-2003 was dominated by (in order of decreasing concentration): natural 40K, 60Co from the plant, 137Cs mainly from the Chernobyl debris, 54Mn and 58Co from the plant. It is not likely that any effects from the very marginal absorbed dose contribution from the Barsebäck NPP releases can be found even in the nearest environment. The study has also shown that the eelgrass Zostera marina may be a bioindicator to use in further studies of the radiation environment in shallow water, especially for 60Co and 54Mn.

Effective conservation requires that arguments for identifying units for preservation and management are based on scientifically sound information. There is a strong conservation concern for the harbour porpoise Phocoena phocoena of the Baltic Sea. This concern rests on the assumption that these porpoises represent a genetically distinct population reproductively separated from adjacent populations to the west. We argue that current scientific support for this claim is weak and to a large degree speculative. Current management of Baltic harbour porpoises as a genetically separate conservation unit is premature and we urge that high priority be given towards resolving this issue.

This article seeks to illustrate the decisive contribution of the sea environment and particularly the sea-surface circulation (which is determined by the circulation of sea currents and the winds) to the early growth of seafaring and maritime communications in the prehistoric Aegean. Given the means and techniques of navigation in that era, an attempt is made to reveal a dense network of sea routes which vessels could follow through the Aegean, in order to facilitate their trip. These sea routes are primarily based on environmental data and are confirmed concurrently by archaeological evidence and data of ancient sources. Therefore, it is evident that these sea routes played an important role not only in the early inhabitation of the Aegean islands and the foundation of coastal settlements throughout the Aegean area from the sixth millennium BC to the end of the third millennium BC, but in the development of the Aegean civilization during earlier prehistoric times as well.