Life depends on healthy oceans that provide ecosystem services (ES) to humans, including provisioning, regulating, supporting, and cultural ES (Kovalenko et al., 2023). However, biodiversity, habitats, and the delivery of marine ES and resources are increasingly threatened by growing human activities in the oceans (Worm et al., 2006). Blue-growth activities, such as shipping and energy, eutrophication, and climate change represent major pressures that affect marine ecosystems (Halpern et al., 2008; Ehlers, 2016). Over the past two decades, increasing scientific attention has focused on the need to preserve and restore healthy marine waters and their role in adapting to climate change (Santos et al., 2020). This challenge calls for holistic approaches that advance our knowledge. Within the contributions to this Research Topic (see Figure 1), three themes are central to driving further research to expand our understanding in this interdisciplinary field.
Although the concept of ecosystem services has been in use for many decades, its application for policy support is limited, particularly with respect to marine ecosystems. Gaps in the assessments of ecosystem services supply prevent its empirical application. We advance these assessments by providing an assessment tool, which links marine ecosystem components, functions and services, and graphically represents the assessment process and its results. The tool consists of two parts: (i) a matrix following the ecosystem services cascade structure for quantifying the contribution of ecosystem components in the provision of ecosystem services; (ii) and a linkage diagram for visualizing the interactions between the elements. With the aid of the Common International Classification of Ecosystem Services (CICES), the tool was used to assess the relative contribution of a wide range of marine ecosystem components in the supply of ecosystem services in the Latvian marine waters. Results indicate that the tool can be used to assess the impacts of environmental degradation in terms of ecosystem service supply. These impacts could further be valued in socioeconomic terms, as changes in the socioeconomic values derived from the use of ecosystem services. The tool provides an opportunity for conducting a holistic assessment of the ecosystem service supply and communicating the results to marine spatial planning practitioners, and increasing their understanding and use of the ecosystem service concept.
This paper presents experimental measurements of beaching times for buoyant microplastic particles released, both in the pre-breaking region and within the surf zone. The beaching times are used to quantify cross-shore Lagrangian transport velocities of the microplastics. Prior to breaking the particles travel onshore with a velocity close to the Lagrangian fluid particle velocity, regardless of particle characteristics. In the surf zone the Lagrangian velocities of the microplastics increase and become closer to the wave celerity. Furthermore, it is demonstrated that particles having low Dean numbers (dimensionless fall velocity) are transported at higher mean velocities, as they have a larger tendency to be at the free-surface relative to particles with higher Dean numbers. An empirical relation is formulated for predicting the cross-shore Lagrangian transport velocities of buoyant microplastic particles, valid for both non-breaking and breaking irregular waves. The expression matches the present experiments well, in addition to two prior studies.
This paper introduces an interactive method which aims to map out perspectives on the state of ecosystem-based approaches (EbA) in marine spatial planning (MSP). MSP meets a need for organizing the allocation of space to maritime uses. MSP should also control and limit the pressures induced by these activities on marine ecosystems. To evaluate how EbA is actually applied, this research proposes a participatory method to assess the effectiveness of current EbA practices within the MSP process using perceptual maps. The mapping focuses on two dimensions: relevance and implementation of a set of 13 key elements of EbA. The method was tested on a sample of marine planners from ongoing MSP processes in northern European sea basins. The study shows that perceptual maps provide four main benefits: participatory, visualization capacity, qualitative and quantitative applicability, and easy to use. This tool undoubtedly has the potential to illustrate the state of integration of EbA in MSP and highlight the priority issues to develop in future plans, and consequently to provide keys to revise marine plans in a way that better takes into account EbA principles.
Rapporter fra flere globale miljøinstitutioner, her
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under den internationale science-policy platform
om biodiversitet og økosystemtjenester (herefter
IPBES), understreger behovet for genopretning af
økosystemer (1,2). Den seneste globale IPBES-rap
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port fra maj 2019 peger således på, at forringelser
af økosystemer på land og i havet underminerer
livsgrundlaget for 3,2 milliarder mennesker. Gen
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opretning bliver fremhævet som en af de vigtig
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ste handlemuligheder for effektivt at begrænse
tabet af biodiversitet og forbedre livsgrundlaget
for os mennesker ved at imødegå forringelser for
en række økosystemtjenester. Det nuværende årti
2021-2030 er af UNEP udpeget til årtiet for genop
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retning med det formål at genetablere ødelagte
eller forarmede økosystemer verden over.
IPBES rapporterne dokumenterer, at biodiversi
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tetskrisen er en altomfattende og global udfor
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dring, og at krisen er på linje med klimakrisen. De
tiltagende klimaændringer er ligeledes en af ho
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vedårsagerne til tab af biodiversitet (2). Der er af
hensyn til begge kriser behov for, at der beskyttes
og genetableres velfungerende og uforstyrrede
økosystemer. Der bør derfor ske en national ud
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møntning af resultaterne fra de internationale aftaler baseret på den bedst tilgængelige viden.
This article examines the historical development of the Greenland shark (Somniosus microcephalus) fishery in North Greenland from 1774-1898. The purpose of the article is to present a starting point, a so-called baseline, for further studies of the extent of the historical fishery. With data from mainly two archival series, the historical catch figures are presented, which has led to the year 1862 as a realistic baseline for the historical fishery of the Greenland shark in North Greenland.
Non-indigenous species (NIS) pose a major threat to biodiversity and the functioning and services of ecosystems. Despite their rapid spread in coastal waters worldwide, biotic invasions are widely disregarded in marine conservation planning. To guide conservation actions, a better understanding of the underlying mechanisms determining the success of NIS are therefore needed. Here we develop a combined modelling approach to identify the key drivers and community assembly processes determining the occurrence of invasive benthic invertebrates, using Danish coastal waters as a case study. To reflect factors affecting the introduction, establishment and spread of NIS throughout the area, we compiled long-term monitoring data on NIS, as well as information on commercial shipping, environmental conditions and estimates of larvae settling densities derived from drift model simulations informed by species traits. We then applied a set of species distribution models to identify the key drivers determining the occurrence of NIS. Our results demonstrate a significant positive effect of vessel activity, a negative effect of depth and bottom salinity, as well as a positive effect of the simulated settling densities on the probability of presence. Taken together, our results highlight the role of commercial shipping, habitat characteristics and passive advection of early-life stages on the presence of NIS. Our combined modelling approach provide improved process understanding on the key community assembly processes determining the presence of NIS and may serve to guide monitoring, management and conservation planning in order to limit future invasions and their negative consequences on coastal ecosystems.
This paper presents a wave flume investigation of beaching times for buoyant microplastic particles dropped at various distance from the shoreline. The beaching times are used to quantify the cross-shore Lagrangian transport velocities of the microplastic particles. Results show that prior to breaking, there is little dependence on particle characteristics (e.g. their rise velocity), and the particles travel onshore with a velocity close to the Lagrangian fluid particle velocity. In the surf zone the Lagrangian transport velocities of the microplastic particles increase significantly, becoming closer to the wave celerity. Additionally, particle characteristics become important, as particles with low Dean numbers (high rise velocity) have a greater tendency to be captured by surface rollers relative to particles with larger Dean numbers (lower rise velocity). An empirical relation is formulated for predicting the cross-shore Lagrangian transport velocities of buoyant microplastic particles. The expression matches the present experiments well and is valid for both non-breaking and breaking irregular waves. These findings help in understanding the accumulation of microplastics at beaches due to the surf-zone processes, especially for buoyant particles.
Crude oil and cadmium (Cd) are common pollutants in Ghana's coastal ecosystems, where the cyanobacterial phytoplankton Synechococcus sp. serves as the primary producer and forms the base of the marine food web alongside small grazers. We hypothesized that cadmium and crude oil would disrupt microbial community structure and function, with the strongest effects under combined exposure. This study investigates the toxic effects of Oil (2 mL L−1), Cd (4.4 μg L−1), and their combined impact (Cd + Oil) on functional groups within the coastal microbial community, including Synechococcus sp., heterotrophic bacteria, nanoflagellates, eukaryotic phytoplankton, ciliates, and dinoflagellates, as well as on copepod nauplii and copepodite development during six-day incubations. We observed acute toxic effects on heterotrophic ciliates and dinoflagellates, with >50 % reductions in abundance within 6 h and a marked decrease in diversity. Phytoplankton showed growth within the first 24 h due to nutrient replenishment from the protist decay, however, their growth continued to decline after 24 h, with Synechococcus being particularly sensitive to Cd and less affected by Oil. In contrast, heterotrophic bacteria increased in abundance across all treatments, likely benefiting from organic matter released during phytoplankton decay and their high adaptability. Notably, the bacterial genera Marivivens and Rhodovulum became dominant mainly in the Oil-amended treatments. Overall, the microbial groups exhibited diverse responses to the pollutants, with the combined Cd + Oil treatment exerting the strongest negative effects, while crude oil alone had the least impact. These findings highlight the vulnerability of tropical microbial food webs, typically dominated by Synechococcus and microbial grazers, to combined pollutant stress, with potential cascading effects on higher trophic levels and coastal ecosystem productivity. This highlights the need for comprehensive monitoring and conservation efforts in these globally significant, yet understudied, regions.
The concept of 'seal-fishery conflict' is used when referring to the complex contradictions stemming from seals' impacts on fishing livelihoods, a pertinent social struggle between stakeholder groups of the Baltic Sea. Tensions are most remarkable between coastal fisheries and seal conservationists. As existing knowledge has been scattered and the conflict has become increasingly problematic, the RESOCO project compiled Nordic knowledge and best practices and built an interdisciplinary synthesis to set the stage for alternative solutions on how to effectively reconcile the seal-fishery conflict in the Baltic Sea. The report takes a pragmatic stand by turning the attention to approaches and instruments that have been suggested to be helpful or that have the potential to help mitigate the conflict. The report synthesizes knowledge and presents existing gaps and needs of further research.