| 1. |
- Dahl, Martin, et al.
(författare)
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A temporal record of microplastic pollution in Mediterranean seagrass soils
- 2021
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Ingår i: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 273
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Tidskriftsartikel (refereegranskat)abstract
- Plastic pollution is emerging as a potential threat to the marine environment. In the current study, we selected seagrass meadows, known to efficiently trap organic and inorganic particles, to investigate the concentrations and dynamics of microplastics in their soil. We assessed microplastic contamination and accumulation in 210Pb dated soil cores collected in Posidonia oceanica meadows at three locations along the Spanish Mediterranean coast, with two sites located in the Almería region (Agua Amarga and Roquetas) and one at Cabrera Island (Santa Maria). Almería is known for its intense agricultural industry with 30 000 ha of plastic-covered greenhouses, while the Cabrera Island is situated far from urban areas. Microplastics were extracted using enzymatic digestion and density separation. The particles were characterized by visual identification and with Fourier-transformed infrared (FTIR) spectroscopy, and related to soil age-depth chronologies. Our findings showed that the microplastic contamination and accumulation was negligible until the mid-1970s, after which plastic particles increased dramatically, with the highest concentrations of microplastic particles (MPP) found in the recent (since 2012) surface soil of Agua Amarga (3819 MPP kg-1), followed by the top-most layers of the soil of the meadows in Roquetas (2173 kg-1) and Santa Maria (68-362 kg-1). The highest accumulation rate was seen in the Roquetas site (8832 MPP m-2 yr-1). The increase in microplastics in the seagrass soil was associated to land-use change following the intensification of the agricultural industry in the area, with a clear relationship between the development of the greenhouse industry in Almería and the concentration of microplastics in the historical soil record. This study shows a direct linkage between intense anthropogenic activity, an extensive use of plastics and high plastic contamination in coastal marine ecosystems such as seagrass meadows. We highlight the need of proper waste management to protect the coastal environment from continuous pollution.
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| 2. |
- Majtényi-Hill, Claudia, 1998, et al.
(författare)
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Inorganic carbon outwelling from a Mediterranean seagrass meadow using radium isotopes
- 2023
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Ingår i: Estuarine, Coastal and Shelf Science. - : Elsevier BV. - 0272-7714. ; 283
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Tidskriftsartikel (refereegranskat)abstract
- Seagrass meadows are ‘blue carbon’ ecosystems widely recognised for their potential role in climate change mitigation. Previous studies have focused mainly on carbon storage within meadows and sediments. However, little is known about contribution of outwelling (i.e., lateral transport) to seagrass carbon budgets. Here, radium isotopes (223Ra and 224Ra) were used to assess dissolved inorganic carbon (DIC) and total alkalinity (TA) outwelling from a Mediterranean Posidonia oceanica meadow during early autumn. DIC outwelling was 114 ± 61 mmol m−2 day−1 and exceeded above-meadow CO2 outgassing (3 ± 1 mmol m−2 day−1). Production of DIC was uncoupled from TA and fuelled by net heterotrophy and aerobic processes within the meadow. The small export of TA (5 ± 6 mmol m−2 day−1) implied that ∼90% of outwelled DIC may return to the atmosphere as CO2 in offshore waters. Combining these fluxes with above-meadow outgassing suggested a total carbon loss that exceeded long term burial in sediments. Overall, the meadow acted as a carbon source to the atmosphere during the early autumn season. Further studies quantifying outwelling at multiple spatial and temporal scales are required to better resolve seagrass carbon budgets and their contribution to carbon sequestration.
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| 3. |
- Nordlund, Lina Mtwana, et al.
(författare)
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One hundred priority questions for advancing seagrass conservation in Europe
- 2024
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Ingår i: PLANTS PEOPLE PLANET. - 2572-2611.
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Tidskriftsartikel (refereegranskat)abstract
- Societal Impact StatementSeagrass ecosystems are of fundamental importance to our planet and wellbeing. Seagrasses are marine flowering plants, which engineer ecosystems that provide a multitude of ecosystem services, for example, blue foods and carbon sequestration. Seagrass ecosystems have largely been degraded across much of their global range. There is now increasing interest in the conservation and restoration of these systems, particularly in the context of the climate emergency and the biodiversity crisis. The collation of 100 questions from experts across Europe could, if answered, improve our ability to conserve and restore these systems by facilitating a fundamental shift in the success of such work.SummarySeagrass meadows provide numerous ecosystem services including biodiversity, coastal protection, and carbon sequestration. In Europe, seagrasses can be found in shallow sheltered waters along coastlines, in estuaries & lagoons, and around islands, but their distribution has declined. Factors such as poor water quality, coastal modification, mechanical damage, overfishing, land-sea interactions, climate change and disease have reduced the coverage of Europe's seagrasses necessitating their recovery. Research, monitoring and conservation efforts on seagrass ecosystems in Europe are mostly uncoordinated and biased towards certain species and regions, resulting in inadequate delivery of critical information for their management. Here, we aim to identify the 100 priority questions, that if addressed would strongly advance seagrass monitoring, research and conservation in Europe. Using a Delphi method, researchers, practitioners, and policymakers with seagrass experience from across Europe and with diverse seagrass expertise participated in the process that involved the formulation of research questions, a voting process and an online workshop to identify the final list of the 100 questions. The final list of questions covers areas across nine themes: Biodiversity & Ecology; Ecosystem services; Blue carbon; Fishery support; Drivers, Threats, Resilience & Response; Monitoring & Assessment; Conservation & Restoration; Governance, Policy & Management; and Communication. Answering these questions will fill current knowledge gaps and place European seagrass onto a positive trajectory of recovery. Seagrass ecosystems are of fundamental importance to our planet and wellbeing. Seagrasses are marine flowering plants which engineer ecosystems that provide a multitude of ecosystem services, for example, blue foods and carbon sequestration. Seagrass ecosystems have largely been degraded across much of their global range. There is now increasing interest in the conservation and restoration of these systems, particularly in the context of the climate emergency and the biodiversity crisis. The collation of 100 questions from experts across Europe could, if answered, improve our ability to conserve and restore these systems by facilitating a fundamental shift in the success of such work. image
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| 4. |
- Piñeiro-Juncal, Nerea, et al.
(författare)
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Review of the physical and chemical properties of seagrass soils
- 2022
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Ingår i: Geoderma. - : Elsevier BV. - 0016-7061 .- 1872-6259. ; 428
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Tidskriftsartikel (refereegranskat)abstract
- Seagrasses are a polyphyletic group of angiosperms that colonized marine environments more than 30 million years ago and currently inhabit coastal soft and rocky substrates in all continents except Antarctica. Due to their evolution from terrestrial plants, seagrasses have belowground organs that interact with the substrate, transforming it through chemo-physical processes analogous to terrestrial soil formation. Although seagrass substrates provide valuable ecosystem services including carbon and coastal stabilization, they have been largely regarded as sediments by marine scientists and neglected in soil science research. However, over the last decades, the increasing interest in carbon accumulation by seagrasses has generated multiple data on seagrass soil physical and chemical characteristics. Here, we review clay and silt content (<0.063 mm particle size), redox potential, pH, carbonate content, organic carbon or organic matter contents, dry bulk density, porosity and color of seagrass soils worldwide, summarizing data typically used for soil description, and looking for generalities in soil characteristics across seagrass habitats. The data gathered was biased towards temperate species and high-income countries, while data about color, porosity, redox potential and pH was scarce. Soil characteristics did not show significant differences among seagrass bioregions. Most seagrass substrates showed sandy textures, whereas one of the most sampled genera, Posidonia, was not present in muddy substrates. The soil Corg content was significantly higher in meadows formed by persistent species (mean ± SD; 1.76 ± 2.17 %) than in meadows formed by species with opportunistic and colonizing life-strategies (1.52 ± 2.24 and 0.76 ± 0.95 %, respectively), while mud content was significantly higher in meadows formed by opportunistic and colonizing species (27.87 ± 29.58 and 21.23 ± 21.77 %, respectively) than in those formed by persistent species (11.83 ± 14.45 %). Redox potential was significantly lower in intertidal than in subtidal meadows, although caution is needed when interpreting these differences due to methodological limitations. This review provides an overview of current knowledge on seagrass soil characteristics, while identifying knowledge gaps in seagrass soil science, including geographical, species diversity and soil physico-chemical traits that limit our capacity to characterize and classify seagrass soils worldwide.
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