Knowledge

Keyword: marine environment

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Reflections on the Implications of Environmental Norms for Fishing: The Link between the Regulation of Fishing and the Protection of Marine Biological Diversity

Tanaka, Yoshifumi

The aim of this article is to examine the implications of environmental norms for fishing by analysing the South China Sea and Chagos Marine Protected Area cases. In so doing, the article considers the link between the regulation of fishing and the protection of marine biological diversity. Specifically, three issues are to be examined: (1) the implications of Articles 192 and 194(5) of the UN Convention on the Law of the Sea for the regulation of environmentally harmful fishing, (2) the implications of Article 194 of the Convention for the fishing rights of a state, and (3) balance between environmental considerations and the fishing rights of a state. In this connection, the article argues that environmentally harmful fishing can be regarded as a key concept when considering the regulation of fishing from the viewpoints of marine environmental protection.

International Community Law Review, 22(3-4) / 2020
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Rock Armor Slope Stability under Wave Attack in Shallow Water

Jentsje W. van der Meer, Thomas Lykke Andersen & Mads Røge Eldrup

The stability formula for rock slopes under wave attack was revised in Van der Meer (2021), replacing the mean period Tm with the spectral period Tm-1.0. This rewritten formula closely resembles the Modified Van der Meer formula as in the Rock Manual (2007), with differences primarily in coefficients and the use of H2% in the Rock Manual and H1/3 in Van der Meer (2021).

The wave characteristics change significantly in shallow water due to nonlinearities and wave breaking. The result is a significant change in the wave height and period, especially when severe breaking occurs and infragravity waves become significant or even dominate the spectrum. This may lead to very large breaker parameters. At a certain point, existing stability formulas may thus become inaccurate, both the original and the Modified formula for shallow water. The primary objective of this paper is to identify when and where shallow water stability results deviate from established formulas and how these deviations can be described.

The analysis involves an in-depth examination of datasets from Van Gent et al. (2003), Eldrup (2019), and other relevant data to increase the understanding of waves in shallow water and how they affect rock slope stability.

The use of H2% in the Modified Van der Meer formula gives some difficulties as no reliable prediction method is available for that parameter when the relative depth is small, h/Hm0 depth < 1.5. The Van der Meer (2021) formula applies the significant wave height, and it may be chosen as either Hm0 or H1/3. These two parameters are almost identical in deep water for which the formula was derived, but significant differences may occur in shallow water. The application of the Van der Meer formula in shallow water indicates a preference for the use of Hm0 as it describes nonlinear waves better. The main conclusion is that the Van der Meer (2021) formula seems valid much further into the shallow water region than what the Rock Manual (2007) recommends and at least to relative water depths of h/Hm0 deep > 1.5. For shallow water with h/Hm0 depth < 1.5 no systematic trend with the energy period is observed anymore and constant combined stability numbers are given for guidance in preliminary design.

JOURNAL OF COASTAL AND HYDRAULIC STRUCTURES / 2024
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SEANERGY – a spatial tool to facilitate the increase of synergies and to minimize conflicts between human uses at sea

Ida Maria Bonnevie, Henning Sten Hansen & Lise Schrøder

With expanding human uses at sea, the objective of maritime spatial planning (MSP) to promote sustainable coexistence between marine uses becomes an increasingly challenging task. In order to assess coexistence options, both use-use interactions and use-environment interactions are important to explore. Tools for doing cumulative impact assessments (CIA) on the environment provide a means for spatially exploring environmental impacts. Finding inspiration in such ecosystem-based spatial use-environment approaches while drawing on pairwise marine use compatibility knowledge from existing literature, a spatial approach to model potential synergies and conflicts between marine uses through an expert-based scoring system is presented and implemented in SEANERGY, an ArcMap-based opensource toolbox. A test based on Baltic Sea GIS data demonstrates how SEANERGY supplements CIA analyzes with knowledge about potential use-use synergies, potential use-use conflicts, and their spatial extents, useful for optimizing the use of marine space in MSP without putting too much cumulative pressure on the environment.

Environmental Modeling and Software / 2020
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SEANERGY – a spatial tool to facilitate the increase of synergies and to minimize conflicts between human uses at sea

Ida Maria Bonnevie, Henning Sten Hansen & Lise Schrøder

With expanding human uses at sea, the objective of maritime spatial planning (MSP) to promote sustainable coexistence between marine uses becomes an increasingly challenging task. In order to assess coexistence options, both use-use interactions and use-environment interactions are important to explore. Tools for doing cumulative impact assessments (CIA) on the environment provide a means for spatially exploring environmental impacts. Finding inspiration in such ecosystem-based spatial use-environment approaches while drawing on pairwise marine use compatibility knowledge from existing literature, a spatial approach to model potential synergies and conflicts between marine uses through an expert-based scoring system is presented and implemented in SEANERGY, an ArcMap-based opensource toolbox. A test based on Baltic Sea GIS data demonstrates how SEANERGY supplements CIA analyzes with knowledge about potential use-use synergies, potential use-use conflicts, and their spatial extents, useful for optimizing the use of marine space in MSP without putting too much cumulative pressure on the environment.

Environmental Modeling and Software / 2020
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Setting the scene for a multi-map toolset supporting maritime spatial planning by mapping relative cumulative impacts on ecosystem service supply

Aurelija Armoškaitė, Juris Aigars, Ingrīda Andersone, Ida Maria Bonnevie, Henning Sten Hansen, Solvita Strāķe, Miriam von Thenen & Lise Schrøder

The aim of this paper is to provide the foundations for the development of a spatial decision-support toolset that combines cumulative impacts and ecosystem service supply assessments to support what-if scenario analysis in a maritime spatial planning context. Specifically, a conceptual framework for a toolset has been designed in order to introduce a new approach for place-based assessments of change in relative ecosystem service supply in multiple services at a time due to changes in cumulative impacts. Central to the toolset are two pre-existing approaches for relative ecosystem service supply and cumulative impact assessments and tools that facilitate them. The tools take advantage of available data from various sources, including geodata and expert knowledge, and have already been proven to support maritime spatial planning in a real-world context. To test the new approach and demonstrate the outputs, an ecosystem service supply assessment was done manually using the two currently separate tools. The results of the test case ecosystem service supply assessment for the Gulf of Riga in the Baltic Sea are also presented in this paper and illustrate the assessment steps and data needs. Although presently the focus of the illustrative assessment is the Gulf of Riga, the toolset will be able to accommodate analysis of cumulative impacts and service supply of any location, leaving the scope of the assessment to be determined by the objectives of the assessment as well as data availability (i.e., geospatial data availability and extent of expert knowledge).

Frontiers in Marine Science / 2023
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Setting the scene for a multi-map toolset supporting maritime spatial planning by mapping relative cumulative impacts on ecosystem service supply

Aurelija Armoškaitė, Juris Aigars, Ingrīda Andersone, Ida Maria Bonnevie, Henning Sten Hansen, Solvita Strāķe, Miriam von Thenen & Lise Schrøder

The aim of this paper is to provide the foundations for the development of a spatial decision-support toolset that combines cumulative impacts and ecosystem service supply assessments to support what-if scenario analysis in a maritime spatial planning context. Specifically, a conceptual framework for a toolset has been designed in order to introduce a new approach for place-based assessments of change in relative ecosystem service supply in multiple services at a time due to changes in cumulative impacts. Central to the toolset are two pre-existing approaches for relative ecosystem service supply and cumulative impact assessments and tools that facilitate them. The tools take advantage of available data from various sources, including geodata and expert knowledge, and have already been proven to support maritime spatial planning in a real-world context. To test the new approach and demonstrate the outputs, an ecosystem service supply assessment was done manually using the two currently separate tools. The results of the test case ecosystem service supply assessment for the Gulf of Riga in the Baltic Sea are also presented in this paper and illustrate the assessment steps and data needs. Although presently the focus of the illustrative assessment is the Gulf of Riga, the toolset will be able to accommodate analysis of cumulative impacts and service supply of any location, leaving the scope of the assessment to be determined by the objectives of the assessment as well as data availability (i.e., geospatial data availability and extent of expert knowledge).

Frontiers in Marine Science / 2023
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SPACEA: A Custom-Made GIS Toolbox for Basic Marine Spatial Planning Analyses

Miriam von Thenen, Henning Sten Hansen & Kerstin S. Schiele

Marine Spatial Planning (MSP) requires the analysis of the spatial distribution of marine uses and environmental conditions. Such analyzes can be carried out with GIS, but standard GIS programs do not feature a toolbox that combines the most needed functionalities for such analyses. The SPACEA toolbox presented here was created to bundle and adapt existing functionalities in one toolbox. SPACEA consists of several script tools that have been designed to be user-friendly and applicable to different analyzes for MSP. This includes the processing of different input layers with regard to marine uses and environmental conditions. The main functionalities of SPACEA are exemplified in a fictional case study in the Baltic Sea, where the tools are applied to find potentially suitable areas for mussel farming. The tools feature a user-friendly interface and more experienced users may also use the provided sample codes to run it from the python window or as a stand-alone script. As such, the tools can be applied by users with different levels of GIS knowledge and experience.

Jumper / 2020
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Spectral element FNPF simulation of focused wave groups impacting a fixed FPSO-type body

Allan P. Engsig-Karup & Claes Eskilsson

A 3D fully nonlinear potential flow (FNPF) model based on an Eulerian formulation is presented. The model is discretized using high-order prismatic – possibly curvi-linear – elements using a spectral element method (SEM) that has support for adaptive unstructured meshes. The paper presents details of the FNPF-SEM development and the model is illustrated to exhibit exponential convergence. The model is then applied to the case of focused waves impacting on a surface-piecing fixed FPSO-like structure. Good agreement was found between numerical and experimental wave elevations and pressures.

International Journal of Offshore and Polar Engineering / 2019
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Struggling towards co-existence of the Baltic Sea coastal fisheries and the grey seal

Kristina Svels, Pekka Salmi, Nelson F. Coelho, Viktor Eriksson, Sara Königson, Esa Lehtonen, Sven-Gunnar Lunneryd, Petri Suuronen, Markus Vetemaa & Åsa Waldo

Commercial small-scale fisheries along the Baltic Sea coasts have declined over the years although these fisheries are viewed as important for coastal development and food security at the local, national, and EU levels. The viability and future of small-scale fisheries are severely challenged by problems caused by grey seals. The conflict, occurring between Baltic Sea coastal fisheries and conservation of the grey seals, has been severe since the mid-1990s and continues despite attempts to find a more balanced situation. Resting on reviews of multiple material, this paper explores the state-of-the-art opportunities for mitigating the seal-fisheries conflict and asks how these are related to social struggles and social justice. Our paper concludes that co-existence of coastal fisheries and the grey seal is possible but necessitates political will and co-designed seal management plans that help implement context-specific measures. Seal deterrents, for instance, give hope as a supplementary conflict mitigation measure – along with seal-proof fishing gear – but provide only partial relief. From the fisheries sector’s position, influencing the size of the seal population is a logical solution. The lifting of the EU trade ban of seal products as a regional derogation would allow sustainable management of seal populations so that they be used as renewable natural resource. Monitoring changes in the seal population is crucial for maintaining a balanced population. Reaching co-existence is timely, because – unlike the seal – the diverse Baltic coastal fishing culture is increasingly endangered.

M A S T. Maritime Studies / 2025
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Supporting integrative maritime spatial planning by operationalising SEANERGY – a tool to study cross-sectoral synergies and conflicts

Ida Maria Bonnevie, Henning Sten Hansen & Lise Schrøder

With growing pressures on marine ecosystems and on marine space, an increasingly needed strategy to optimize the use of marine space is to co-locate synergic marine human uses in close spatial–temporal proximity while separating conflicting marine human uses. The ArcMap toolbox SEANERGY is a new, cross-sectoral spatial decision support tool (DST) that enables maritime spatial planners to consider synergies and conflicts between marine uses to support assessments of co-location options. Cross-sectoral approaches are important to reach more integrative maritime spatial planning (MSP) processes. As this article demonstrates through a Baltic Sea analysis, SEANERGY presents a crosssectoral use catalog for MSP through enabling the tool users to answer important specific questions to spatially and/or numerically weight potential synergies/conflicts between marine uses. The article discusses to what degree such a cross-sectoral perspective can support integrative MSP processes. While MSP integrative challenges still exist, SEANERGY enables MSP processes to move towards developing shared goals and initiate discussions built on best available knowledge regarding potential use-use synergies and use-use conflicts for whole sea basins at once.

International Journal of Digital Earth / 2021
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