A modelling evaluation of electromagnetic fields emitted by buried subsea power cables and encountered by marine animals : considerations for marine renewable energy development

Part of this work was supported by the Bureau of Ocean Energy Management (contract number M14PC00009).The expanding marine renewable energy industry will increase the prevalence of electromagnetic fields (EMFs) from power cables in coastal waters. Assessments of environmental impacts are required within licensing/permitting processes and increased prevalence of cables will increase questions concerning EMF emissions and potential cumulative impacts. It is presumed that protecting a cable by burial, may also mitigate EMF emissions and potential impacts on species. Focussing on a bundled high voltage direct current (HVDC) transmission cable, we use computational and interpretive models to explore the influence of cable properties and burial depth on the DC magnetic field (DC-MF) potentially encountered by receptive species. Greater cable pair separation increased the deviations from the geomagnetic field and while deeper burial reduced the deviations, the DC-MF was present at intensities perceivable by receptive species. An animal moving along a cable route may be exposed to variable EMFs due to varied burial depth and that combined with an animal’s position in the water column determines the distance from source and EMF exposure. Modelling contextually realistic scenarios would improve assessments of potential effects. We suggest developers and cable industries make cable properties and energy transmission data available, enabling realistic modelling and environmental assessment supporting future developments.PostprintPeer reviewe

Anthropogenic electromagnetic fields (EMF) influence the behaviour of bottom-dwelling marine species

Funding: Bureau of Ocean Energy Management (contract number M14PC00009), representing an integrated analysis drawn from the work fully reported in OCS Study Report Number BOEM 2018-003.Many marine animals have evolved sensory abilities to use electric and magnetic cues in essential aspects of life history, such as to detect prey, predators and mates as well as to orientate and migrate. Potential disruption of vital cues by human activities must be understood in order to mitigate potential negative influences. Cable deployments in coastal waters are increasing worldwide, in capacity and number, owing to growing demands for electrical power and telecommunications. Increasingly, the local electromagnetic environment used by electro- and magneto-sensitive species will be altered. We quantified biologically relevant behavioural responses of the presumed, magneto-receptive American lobster and the electro-sensitive Little skate to electromagnetic field (EMF) emissions of a subsea high voltage direct current (HVDC) transmission cable for domestic electricity supply. We demonstrate a striking increase in exploratory/foraging behaviour in skates in response to EMF and a more subtle exploratory response in lobsters. In addition, by directly measuring both the magnetic and electric field components of the EMF emitted by HVDC cables we found that there were DC and unexpectedly AC components. Modelling, restricted to the DC component, showed good agreement with measured results. Our cross-disciplinary study highlights the need to integrate an understanding of the natural and anthropogenic EMF environment together with the responses of sensitive animals when planning future cable deployments and predicting their environmental effects.Publisher PDFPeer reviewe

Judicial review of the decisions of public authorities in matters of private law

The presented dissertation deals with the current legislation of judicial review of administrative decisions in civil matters, which is incorporated into the fifth part of the Code of Civil Procedure. The introduction outlines the historical context of this legislation, as well as the fundamental motives that led to the formation of the current form of the evaluated legal regulations. Attention is also given to specific issues related to the chosen topic, in particular the question of dualistic concept of judicial protection, adopted within the reform of the administrative judiciary effective from 1st January 2003, as well as the issues of a conflict of jurisdictions, which is one of the consequences of exclusion of the review of decisions of public authorities about private individual rights from the jurisdiction of courts deciding in administrative judiciary, and assigning this agenda to civil courts, which occurred within the context of the mentioned reform. The focus of this work is to describe the valid and effective fifth part of the Code of Civil Procedure, within which a special emphasis is placed on the problematic aspects of this legislation. The main aim will be to clarify or explain controversial provisions, if needed using case law, as well as the publications expressing sometimes conflicting..

Sediment Burial Intolerance of Marine Macroinvertebrates

<div><p>The marine environment contains suspended particulate matter which originates from natural and anthropogenic sources. Settlement of this material can leave benthic organisms susceptible to smothering, especially if burial is sudden i.e. following storms or activities such as dredging. Their survival will depend on their tolerance to, and their ability to escape from burial. Here we present data from a multi-factorial experiment measuring burial responses incorporating duration, sediment fraction and depth. Six macroinvertebrates commonly found in sediment rich environments were selected for their commercial and/or conservation importance. Assessments revealed that the brittle star (<i>Ophiura ophiura</i>), the queen scallop (<i>Aequipecten opercularis</i>) and the sea squirt (<i>Ciona intestinalis</i>) were all highly intolerant to burial whilst the green urchin (<i>Psammichinus miliaris</i>) and the anemone (<i>Sagartiogeton laceratus</i>), showed intermediate and low intolerance respectively, to burial. The least intolerant, with very high survival was the Ross worm (<i>Sabellaria spinulosa</i>). With the exception of <i>C</i>. <i>intestinalis</i>, increasing duration and depth of burial with finer sediment fractions resulted in increased mortality for all species assessed. For <i>C</i>. <i>intestinalis</i> depth of burial and sediment fraction were found to be inconsequential since there was complete mortality of all specimens buried for more than one day. When burial emergence was assessed <i>O</i>. <i>ophiura</i> emerged most frequently, followed by <i>P</i>. <i>miliaris</i>. The former emerged most frequently from the medium and fine sediments whereas <i>P</i>. <i>miliaris</i> emerged more frequently from coarse sediment. Both <i>A</i>. <i>opercularis</i> and <i>S</i>. <i>laceratus</i> showed similar emergence responses over time, with <i>A</i>. <i>opercularis</i> emerging more frequently under coarse sediments. The frequency of emergence of <i>S</i>. <i>laceratus</i> increased with progressively finer sediment and <i>C</i>. <i>intestinalis</i> did not emerge from burial irrespective of sediment fraction or depth. Finally, and perhaps unsurprisingly, the greatest ability to emerge from burial in all other species was from shallow (2 cm) burial. Although survival was consistently highly dependent on duration and depth of burial as expected, emergence behaviour was not as easily predictable thereby confounding predictions. We conclude that responses to burial are highly species specific and therefore tolerance generalisations are likely to be oversimplifications. These data may be used to inform environmental impact models that allow forecasting of the cumulative impacts of seabed disturbance and may provide mitigation measures for the sustainable use of the seabed.</p></div

a-c. Multispecies assessment of emergence (%) in response to sediment burial.

<p>Factors assessed: a) Duration (days); b) Sediment fraction (C = course, M = medium, F = fine) and; c) Depth of burial (cm) above organism.</p

Indicators of mortality used to assess organisms following burial treatments.

<p>Indicators of mortality used to assess organisms following burial treatments.</p

a-c. Multispecies assessment of mortality (%) in response to sediment burial.

<p>Factors tested: a) Duration (days); b) Sediment fraction (C = course, M = medium, F = fine) and; c) Depth of burial (cm) above organism.</p

<i>Sabellaria spinulosa</i> clump with ‘emergence tubes’.

<p>‘Emergence tubes’ constructed during burial by 2 cm fine (0.1–0.25 mm) sand for 16 days. The inset (top left) shows an isolated emergence tube which breaks off the main parent colony easily, and through which an individual animal is clearly visible. The inset (bottom left) shows three tubes emerging from the sediment following burial (Image source: Kim Last).</p