The deterioration of marine ecosystems, such as pollution and coastal eutrophication (overflow of nutrients in water), has become a global challenge. Oceans are reported to mitigate the impact of climate change by absorbing roughly 23% of the annual emissions of various forms of carbons, the most concerning being carbon dioxide. Carbon sequestration in freshwater, coastal and oceanic vegetated ecosystems (such as wetlands, mangroves, seagrass meadows, and salt marshes), so-called “blue carbon ecosystems” may contribute to climate change mitigation. Consequently, conservation, expansion, and sustainable use of these ecosystems have begun to be included in national policies and strategies for reducing atmospheric greenhouse gas levels and climate change adaptation (e.g., Nationally Determined Contributions; NDCs). However, weather/climate variations, biodiversity spectrums, and anthropogenic activities (e.g., non-sustainable resource extraction, land-based pollution and habitat degradation) across the geological sites could alter hydrology, biogeochemistry of carbon and thus the greenhouse gas dynamics; thereby driving the fragile balance of BCE as carbon sinks or sources. In contrast to the open sea, higher spatiotemporal variation in carbon quantity and flux was observed in coastal and estuary ecosystems due to intensive anthropogenic activities, natural biological processes and substantial terrestrial loads.
Dead zones refer to low-oxygen (or hypoxic) areas that occur in marine ecosystems primarily resulting from eutrophication, which happens when nutrient concentrations (e.g., phosphorus and nitrogen) increase to higher levels. Eutrophication could naturally occur; however, human activities are the major cause of these excess nutrients being loaded into the ocean. Dead zones lead to adverse consequences for larger-scale problems in biodiversity, fisheries, and human illness. Dissolved organic matter (DOM) is the major carbon source in aquatic ecosystems and is characterized by a complex mixture of organic compounds. DOM contains a variety of functional groups which can strongly interact with both organic and inorganic pollutants (e.g., metals, carbonaceous materials and hydrophobic contaminants), change their spatiotemporal distribution, and thus affect their transportation, transformation, bioavailability, accumulation and toxicity at the marine ecosystems. Decaying algal blooms in eutrophic coastal ecosystems produce a large quality of DOM into the water. Consequently, understanding the factor and processes that shape the spatiotemporal variations in sources and composition of DOM from natural or anthropogenic activities would benefit the sustainable use of marine resources as well as protect marine ecosystems for sustainable fisheries in both costal and oceanic ecosystems.
Undoubtedly, it is important to clarify the biochemical reaction on dissolved inorganic carbon (DIC), total alkalinity (TA) and pH in BCEs, such as the effect of phytoplankton, submerged aquatic vegetation, shellfish and aquatic habitats on carbon fluxes. This collection welcomes papers on these topics. In addition to BCEs, since the water area of freshwater lakes is more than twice as large as shallow coastal regions, there is the potential to capture and store carbon in inland waters, which has not been understood sufficiently. Thus, this special issue also pays attention to not only coastal BCEs but also "freshwater blue carbon ecosystems". This collection welcomes manuscripts related to carbon dynamics in freshwater, coastal and oceanic ecosystems, including but not limited to GHG emission/storage (blue carbon), acidification, fishery resource and marine pollution (such as eutrophication, dead zone and metal pollution). This special issue aims to reach comprehensive and innovative understandings that contribute to the target topic of SDG Goals in Climate Action (Goal 13) and Life Below Water (Goal 14).
The deterioration of marine ecosystems, such as pollution and coastal eutrophication (overflow of nutrients in water), has become a global challenge. Oceans are reported to mitigate the impact of climate change by absorbing roughly 23% of the annual emissions of various forms of carbons, the most concerning being carbon dioxide. Carbon sequestration in freshwater, coastal and oceanic vegetated ecosystems (such as wetlands, mangroves, seagrass meadows, and salt marshes), so-called “blue carbon ecosystems” may contribute to climate change mitigation. Consequently, conservation, expansion, and sustainable use of these ecosystems have begun to be included in national policies and strategies for reducing atmospheric greenhouse gas levels and climate change adaptation (e.g., Nationally Determined Contributions; NDCs). However, weather/climate variations, biodiversity spectrums, and anthropogenic activities (e.g., non-sustainable resource extraction, land-based pollution and habitat degradation) across the geological sites could alter hydrology, biogeochemistry of carbon and thus the greenhouse gas dynamics; thereby driving the fragile balance of BCE as carbon sinks or sources. In contrast to the open sea, higher spatiotemporal variation in carbon quantity and flux was observed in coastal and estuary ecosystems due to intensive anthropogenic activities, natural biological processes and substantial terrestrial loads.
Dead zones refer to low-oxygen (or hypoxic) areas that occur in marine ecosystems primarily resulting from eutrophication, which happens when nutrient concentrations (e.g., phosphorus and nitrogen) increase to higher levels. Eutrophication could naturally occur; however, human activities are the major cause of these excess nutrients being loaded into the ocean. Dead zones lead to adverse consequences for larger-scale problems in biodiversity, fisheries, and human illness. Dissolved organic matter (DOM) is the major carbon source in aquatic ecosystems and is characterized by a complex mixture of organic compounds. DOM contains a variety of functional groups which can strongly interact with both organic and inorganic pollutants (e.g., metals, carbonaceous materials and hydrophobic contaminants), change their spatiotemporal distribution, and thus affect their transportation, transformation, bioavailability, accumulation and toxicity at the marine ecosystems. Decaying algal blooms in eutrophic coastal ecosystems produce a large quality of DOM into the water. Consequently, understanding the factor and processes that shape the spatiotemporal variations in sources and composition of DOM from natural or anthropogenic activities would benefit the sustainable use of marine resources as well as protect marine ecosystems for sustainable fisheries in both costal and oceanic ecosystems.
Undoubtedly, it is important to clarify the biochemical reaction on dissolved inorganic carbon (DIC), total alkalinity (TA) and pH in BCEs, such as the effect of phytoplankton, submerged aquatic vegetation, shellfish and aquatic habitats on carbon fluxes. This collection welcomes papers on these topics. In addition to BCEs, since the water area of freshwater lakes is more than twice as large as shallow coastal regions, there is the potential to capture and store carbon in inland waters, which has not been understood sufficiently. Thus, this special issue also pays attention to not only coastal BCEs but also "freshwater blue carbon ecosystems". This collection welcomes manuscripts related to carbon dynamics in freshwater, coastal and oceanic ecosystems, including but not limited to GHG emission/storage (blue carbon), acidification, fishery resource and marine pollution (such as eutrophication, dead zone and metal pollution). This special issue aims to reach comprehensive and innovative understandings that contribute to the target topic of SDG Goals in Climate Action (Goal 13) and Life Below Water (Goal 14).
