Aquaculture is a cornerstone of global aquatic food production, yet its rapid expansion has raised growing concerns about ecological risks and water pollution. Bivalve-macroalgae polyculture, recognized for its substantial ecosystem service potential, offers diverse ecological benefits. However, misaligned culture scales and improper species ratios can drive functional imbalance and trophic bottlenecks, ultimately hindering the recovery of biological resources. Consequently, understanding how variations in culture scale and ratio influence ecosystem dynamics while also balancing ecological risks and restoration benefits is pivotal for the sustainable development of aquaculture. In this study, the Ecopath with Ecosim model was employed to simulate the effects of multiple aquaculture scenarios on ecosystem stability and functional group biomass in Sansha Bay. The results revealed that reducing the bivalve culture scale promoted an increase in the biomass of most functional groups, whereas an expansion of bivalve culture led to a decrease. Although increasing macroalgae culture reduced phytoplankton biomass, it boosted the biomass of other functional groups. When varied individually, enlarging bivalve culture or reducing macroalgae culture enhanced ecosystem stability and maturity, whereas the opposite adjustments diminished these attributes. Within the non-spatial EwE framework used here, an ecologically favorable scenario was identified when bivalve and macroalgae culture scales were reduced to 50% and 60% of their current scales, respectively; under this scenario, the biomass of most functional groups increased by 30-65%, together with improvements in ecosystem maturity and diversity. These findings provide a scenario-based, non-spatial reference for adaptive aquaculture management in Sansha Bay and similar semi-enclosed marine ecosystems, while the proposed culture levels should be further refined through spatially explicit ecological analyses and socioeconomic assessments before implementation.

Seagrass meadows rank among the most productive coastal ecosystems, yet our understanding of their nutrient-acquisition strategies in oligotrophic environments remain fragmented. Current research tends to focus on isolated processes, such as leaf or root uptake, without adequately integrating morpho-physiological traits, sediment heterogeneity, or microbial interactions. This fragmentation constrains our ability to predict seagrass responses to global environmental change. This review synthesizes seagrass nutritional ecology and shows that species in oligotrophic systems employ complementary strategies, including high-affinity foliar absorption, extensive root proliferation, and internal resorption. Crucially, these traits exhibit high plasticity and are modulated by intricate plant-microbe mutualisms, such as nitrogen fixation and phosphorus solubilization. We further demonstrate how sediment properties and hydrodynamic create spatial heterogeneity that dictates site-specific nutrient bioavailability. We propose three priority research directions: (1) deciphering the genetic and epigenetic drivers of phenotypic plasticity adaptation to oligotrophy; (2) applying stable isotope tracers and comparative genomics to quantify the net functional benefits of the seagrass microbiome; and (3) assessing long-term impacts of synergistic stressors (e.g., warming and eutrophication) on meadow structure and biogeochemical functions. By treating oligotrophic environments as natural laboratories, this review informs restoration efforts and the need to safeguard ecosystem services globally, particularly blue carbon sequestration and biodiversity conservation.

Cage aquaculture can increase nutrient loading and exacerbate eutrophication in weakly flushed, semi-enclosed bays, whereas macroalgal cultivation is often expected to enhance nutrient uptake and dissolved oxygen (DO). However, scale-dependent management benchmarks for coordinating these aquaculture types remain poorly constrained. In Sansha Bay, China, we combined seasonal monitoring (2016-2020) with Sentinel-2 mapping to quantify cage-aquaculture and macroalgal cultivation areas within 500-, 1000-, and 1500-m buffers around monitoring stations. Linear mixed-effects models, with season as a random effect and salinity as a proxy for mixing, were used to relate aquaculture area to DO, dissolved inorganic nitrogen (DIN), and soluble reactive phosphorus (SRP). Water quality exhibited a pronounced estuarine-marine gradient. Within 500 m, cageaquaculture area was positively associated with DIN and SRP, whereas macroalgal area was positively associated with DO. At the 1500 m scale, cage-aquaculture area was negatively associated with DIN and SRP, and macroalgal area was negatively associated with DIN; these larger-scale negative associations likely reflect spatial covariation along the estuarine-marine gradient rather than direct mitigation effects. Under the fitted model, maintaining at least 2.12 km2 of macroalgal cultivation within a 1500 m buffer was associated with model-predicted DIN below 0.40 mg center dot L 1 , consistent with the Class III limit in China's Seawater Quality Standard (GB 3097-1997). Under a simple proportional extrapolation to the bay's 406 km2 open-water area, this local threshold would imply a heuristic bay-wide reference of approximately 122 km2 of macroalgal cultivation; this value should not be interpreted as a uniform target because practical implementation would need to account for aquaculture spatial planning, competing space uses, and the distribution of hydrodynamically suitable zones. In contrast, reducing cage-aquaculture area alone was unlikely to lower model-predicted SRP to <= 0.03 mg center dot L 1 . These results provide a scale-explicit reference for aquaculture zoning and integrated multi-trophic aquaculture planning in semi-enclosed coastal bays.

Addressing the growing threat of harmful algal blooms driven by eutrophication and climate change, biomanipulation via fish has emerged as a promising strategy to enhance water quality in lake ecosystems. While biomanipulation is often evaluated by its impact on algal control, the influence of food web structure and function on water quality requires further mechanistic understanding. This study pioneers a 22-year ecosystem-scale analysis using Ecopath with Ecosim (EwE) model to quantify how a dual biomanipulation strategy involving filter-feeding fish and piscivorous fish reshapes energy flow pathways and nitrogen cycling dynamics in a subtropical eutrophic lake. The findings indicate that the introduction of filter-feeding fish (silver carp, Hypophthalmichthys molitrix, and bighead carp, Aristichthys nobilis) suppress cyanobacterial blooms by redirecting 52.7% of nitrogen to fisheries, while piscivorous fish (bass, Lateolabrax japonicus, and eel, Anguilla japonica) amplify trophic cascades, enhancing zooplankton-mediated microalgal regulation. Food web connectivity increased (connectance: 0.12 to 0.21), minimizing nitrogen flux to detritus and improving water quality by 38%, driven by cyanobacterial biomass suppression, enhanced energy transfer efficiency, and fish-mediated nitrogen removal. These results demonstrate that integrated biomanipulation balances fishery yields with eutrophication control, offering a climate-resilient framework for restoring subtropical lakes globally. This work advances mechanistic insights into nutrient-energy synergies and provides actionable strategies for sustainable aquatic management in warming ecosystems.

As anthropogenic pressures intensify, aquatic ecosystems experience biodiversity loss and trophic imbalances that compromise their stability and resilience. Biomanipulation offers a promising avenue for ecological restoration, but its long-term effectiveness remains understudied. Using Yundang Lagoon as a case study, this research employed Ecopath with Ecosim modeling and a "peak reduction and trough filling" strategy to explore trophic structure and ecosystem function. Ten biomanipulation scenarios were tested through Ecosim simulations and trophic level spectrum analyses. In 2008, ecosystem maturity was relatively low, with persistent imbalances characterized by most energy flow being confined to lower trophic levels and a transfer efficiency of only 3.93 %. A comprehensive biomanipulation approach that reduces high-biomass functional groups and supplements lowbiomass groups produced the greatest increases in transfer efficiency, which rose to 10.99 % after three rounds of intervention. Gains in the ecosystem's energy transfer efficiency typically peak in the third year following each intervention, and although the rate of improvement diminishes over time, the lagoon continues to progress toward a more mature and stable state. These findings can inspire ongoing management efforts in Yundang Lagoon and underscore the potential of repeated, targeted biomanipulation for restoring similarly degraded coastal lagoon ecosystems.

Ecological floating bed is an important biological remediation method for water pollution control. During the removal of excess nutrients and pollutants, changes in environmental factors affect the characteristics of microorganisms in aquatic ecosystems. To understand the influences of ecological floating beds on size-fractionated microorganisms, we investigated the community assembly and nitrogen metabolic characteristics of three size-fractionated microorganism groups in the ecological floating bed area, using 18S rDNA, 16S rDNA metabarcoding, and metagenomic sequencing techniques. Firstly, we discovered substantial differences between size-fractionated groups in the diversity and compositions of both microeukaryotic and bacterial communities, as well as the influences of floating beds on specific groups. The floating beds appeared to provide more habitats for heterotrophs and symbiotes while potentially inhibiting the growth of certain phytoplankton (cyanobacteria). Secondly, we observed that microeukaryotic and bacterial communities were predominantly influenced by stochastic and deterministic processes, respectively, and they both exhibited distinct patterns across different size-fractionated groups. Notably, microeukaryotic community assembly demonstrated a greater sensitivity to ecological floating beds, as indicated by an increase in dispersal limitation processes. Finally, the nitrogen metabolism functional genes revealed that microbes associated with large-sized particles played a crucial role in dissimilatory nitrate reduction to ammonium (DNRA) and denitrification processes within the floating bed area, thereby facilitating the removal of excess nitrogen nutrients from the water. In contrast, free-living microorganisms from small-sized groups were linked mainly to the genes involved in nitrogen assimilation and assimilatory nitrate reduction to ammonium (ANRA) processes. These findings help understand the impact of ecological floating beds on the diversity and functional characteristics of microorganism communities in different size-fractionated groups.

The rise in surface ocean temperature imposes strong effects on marine organisms. With large population sizes and fast generation times, microorganisms may rapidly adapt to ocean warming. However, long-term experimental adaptation studies on heterotrophic protists are very limited, hindering our comprehensive understanding of their adaptation capability and the underlying mechanisms. In this study, we conducted long-term thermal selection experiments on six representative marine protozoa. By assessing their phenotypes, metabolism, thermal performance curves, thermal traits, and carbon allocation status, we found that all investigated heterotrophic protists exhibited a fitness-improved adaptation response to warming scenarios. After growing in warmer conditions for hundreds of generations (~850 for Cafeteria burkhardae and ~500 for other species), their optimal temperature and maximum rates of both growth and ingestion increased, whereas respiration rates significantly decreased. In addition, the cell size, cellular carbon, and nitrogen content at an elevated environmental temperature also increased after warming adaptation. Mechanisms underlying the increased competitive fitness at high temperatures after warming adaptation might be associated with the alleviated oxidative stress, shown by the remarkable reduction in cellular reactive oxygen species contents. Our study, for the first time, reveals the ability of marine heterotrophic protists to adapt to higher temperatures, providing experimental support for predictive modeling studies that integrate evolutionary potential with short-term physiological responses, with important implications for marine ecosystem functioning and biogeochemical cycling under global warming.

Microbes of diverse sizes and classifications collaborate to mediate a variety of biogeochemical processes. Although seasonal fluctuations in environmental variables generally influence microbial community dynamics, our comprehension of interdomain microbial co-occurrence patterns remains incomplete. Here, we analyzed high-throughput sequencing datasets of bacteria, pico-protists (0.8–2 μm) and nano-protists (2–20 μm), and their seasonal changes in coastal marine ranching ecosystems. Our findings revealed that, in terms of trophic groups, pico-protists predominantly comprised parasites, whereas nano-protists had a higher proportion of mixotrophs. Microbial communities shifted with seasona, mainly in response to temperature, dissolved oxygen, and salinity. Interdomain microbial networks showed the highest robustness and information transfer efficiency in autumn. This pattern was linked not only to environmental conditions but also to how specialized the protist communities became during that time. The seasonal harvesting of seaweed and stages of fish farming may have contributed to these changes. Our findings suggest that both natural seasonal cycles and mariculture activities together shape how microbial species interact, potentially affecting ecosystem stability and function.

Corals often form reef ecosystems that support diverse marine life, but they are sensitive to environmental fluctuations that can affect their nutrient acquisition. While coral-associated microbes (e.g., Symbiodiniaceae, bacteria and fungi) may supplement nutrients to coral hosts via metabolite translocation and nutrient recycling, the extent to which these microbial partners contribute to coral autotrophy or heterotrophy remains unclear. Here, we seasonally measure the carbon isotopes of amino acids (δ13CAA) in reef-building coral Pocillopora damicornis and its nutrient sources (e.g., Symbiodiniaceae and particulate organic matter). Regional Bayesian mixing models show that P. damicornis increased autotrophy (from 67.1 to 80.5%), but decreased particulate feeding (from 32.9 to 19.5%) from the cool season to the warm season. Stable essential δ13CAA values (valine, leucine and isoleucine) suggest limited seasonal changes in microbial contributions. Linear discriminant analysis, which combines current and published data from basal organisms (e.g., bacteria and fungi) to coral consumers, also reveals limited bacterial and fungal contributions to coral nutrition. Thus, we advocate that coral nutrition is primarily determined by Symbiodiniaceae translocation and particulate feeding. As these nutritional pathways are highly subject to environmental fluctuations, corals lacking trophic flexibility may suffer more from malnutrition and even population decline under global environmental change.

The on-shelf penetration of low-frequency open-ocean signals makes a significant contribution to the variability of coastal sea level. However, owing to the complicated coupling, the high-frequency tidal effects on the shoreward penetration of the low-frequency signals are generally overlooked. This study revisits the classic b-plane arrested topographic wave model aiming to more explicitly reveal the role of tides in modulating the open-ocean sea level transmission over the continental shelf. By inferring and comparing different forms of the vorticity equation, we reexpress the bottom friction coefficient (BFC) as r = f SB = k based on a linear eddy-viscosity parameterization, thereby relating BFC to 7b/r the thickness of the bottom boundary layer SB and further to the bed shear stress (BSS)7b (f being the Coriolis parameter, k being a constant, and r is the seawater density). This provides a novel perspective to examine tidal effects on the across-shelf transmission by estimating enhanced BSS induced with the addition of tidal currents. Using appropriate parameterizations to estimate BSS, we apply the calculations to the western North Atlantic. It is shown that BFC exhibits an abrupt increase between 28 degrees and 35 degrees N by including tidal currents, which enhances the on-shelf penetration of open-ocean signals, especially in the downstream vicinity of 31 degrees N. Moreover, modeling experiments indicate that this enhancement is more evident for shorter-wavelength signals. Such a pronounced coastal response is clearly manifested in tide gauge measurements along the east coast of North America. We also discuss the impact of tidal current rotation on the ocean-to-coast transmission for a constant eddy-viscosity scenario.

Tissue culture is one of the most promising and practical methods for conserving endangered plant species. Therefore, the present study evaluates the conservation of the endangered seaweed Sargassum fusiforme through tissue culturing techniques from different explants for the first time. Besides, the genetic variation of the mother plant and cultivated explants using inter-simple sequence repeat (ISSR) techniques; this methodology was the first to be illustrated in such work for algae tissue culturing. The regeneration results have shown that different explants could induce shoot and rhizoid morphogenesis with a total number of blades of 2436, 1011, 1466, 678, and 6 from apical parts, stipe with blades, two-segmented seedlings, rhizoids, and stipe without blades, respectively. The total length was 234, 181.8, 83.5, and 81.8 cm from the two-segmented seedlings, apical parts, stipe without blades, and stipe with blades, respectively. At the same time, the total wet weight was 73.148, 48.369, 35.731, 18.588, and 2.035 g from the apical parts, the two-segmented seedlings, stipe with blades, rhizoids, and stipe without blades, respectively. Micropropagation of S. fusiforme was successfully achieved with apical, stipe, and stolon segments using free PES media. It is suggested that the applied genetic fingerprint is valid for S. fusiforme and will respond well to molecular marker assistance in cultivation. The significance of S. fusiforme and its exposure to being endangered due to over-exploitation have made its regeneration in vitro a subject of interest in this study. Thus, this report represents the successful regeneration of S. fusiforme and explores the genetic uniformity or somaclonal variation of the obtained seedlings using the ISSR-PCR marker for the first time.

Mangroves provide essential ecological functions and services but face increasing external disturbances, leading to degradation and even mortality. While most studies focus on external drivers of mangrove decline, the role of internal factors remains underexplored. Derris trifoliata, a native climbing vine associated with mangroves, has been reported to cause localized degradation and mortality in recent years. However, the lack of spatial distribution data on D. trifoliata hinders comprehensive mangrove health assessments and management efforts. Here, we developed a multi-level automated classification method integrating spectral characteristics and phenological information to detect D. trifoliata using time-series Sentinel-2 imagery on the Google Earth Engine platform. Focusing on the Beibu Gulf mangrove wetlands, we found that D. trifoliata exhibits distinct seasonal greenness variations and unique spectral reflectance, enabling its effective identification and differentiation from invaded mangrove patches, terrestrial vegetation, and salt marshes. This approach achieved an overall classification accuracy of 93.7 % in the Beibu Gulf region. In 2023, the total D. trifoliata coverage in the coastal zone was 220.49 ha, with 83.14 % (183.33 ha) concentrated in Beihai City and 73.29 % (161.59 ha) distributed in the Lianzhou Bay estuarine delta. D. trifoliata primarily invaded true mangrove communities, especially Aegiceras corniculatum stands, covering 155.51 ha (70.53 % of total invaded area).These results demonstrate the effectiveness of satellite remote sensing in detecting such ecological disturbances and quantify the considerable impact of D. trifoliata on Beibu Gulf mangroves, highlighting the need to prioritize monitoring of its threat to specific mangrove communities (e.g., A. corniculatum).

Strategies for restoring degraded ecosystems vary widely in the levels of human intervention. It has commonly been assumed that recovery with artificial inputs would be quicker and more efficient. However, is this truly the situation? We conducted a meta-analysis to evaluate the differences and applicability between ecological restoration and ecological rehabilitation. Relationships between soil phosphorus content, plant diversity, and soil microbial diversity were analyzed using 463 valid experimental data points collected from 72 publications. The results indicated that in grassland ecosystems, ecological restoration outperformed rehabilitation by 35%, 68%, 38%, and 48% in belowground biomass, community coverage, plant richness, and Shannon diversity, respectively. In forests, rehabilitation trailed behind restoration by 58%, 26%, and 92% in belowground biomass, Simpson diversity, and bacterial Shannon diversity. Furthermore, there was minimal difference in the recovery mode among different fungal and bacterial phyla. Rehabilitation demonstrated lower stability and efficiency in long-term phosphorus cycling compared to restoration. Overall, ecological restoration offers more stable and efficient long-term phosphorus cycling, thereby questioning the effectiveness of ecological rehabilitation for sustainable ecosystem recovery, especially for species diversity and phosphorus cycling.

Background Ecological floating beds can restore eutrophic water,but few studies have focused on changes in microbial communities during the remediation process.To gain a deeper understanding of the restoration process,we used 16S/18S rRNA gene metabarcoding and metagenomic sequencing to investigate the changes in the struc-ture and function of protist and bacterial communities. Results By comparing seawater with or without floating beds,we found that Sesuvium portulacastrum can effec-tively remove nutrients and dissolved solids from water,with nitrate removal above 52％and phosphate removal above 34％within 33 days.S.portulacastrum increased the alpha diversity of both protists and bacteria,changed their community composition,and improved the community stability.The stochastic processes were critical in shaping the community assembly,and the contribution of stochastic processes in floating beds was lower in the treatment group than in the control group.In addition,changes in aquatic community structure further led to changes in com-munity function,particularly nitrogen cycle processes.Among all nitrogen cycle-related functional genes,dissimila-tory nitrate reduction genes(44.50％)and denitrification genes(62.44％)were the most common on day 1 and day 33,respectively.The enhanced denitrification process promoted the nitrogen removal in eutrophic water,contributing to ecological restoration and water quality improvement. Conclusions Our results suggested that S.portulacastrum and associated microbial communities exhibited a syn-ergistic role in the restoration process.The well-developed root system of S.portulacastrum acted as a carrier for microorganisms to play a crucial role in the removal of nutrients and other dissolved solids.This study can provide a reference for the optimization of ecological management of eutrophic seawater.Restoration efforts should inte-grate considerations of water physicochemical properties with the structure and function of aquatic community.

ABSTRACT The microbial food web plays a critical role in marine ecosystems, composed of various cell sizes of microbial organisms. Here, high-throughput sequencing of the 16S and 18S rRNA genes was conducted to detect the community structure and distribution patterns of bacterioplankton (0.2 µm–2 µm) and three size fractions of protist communities, i.e., pico-protist (0.2 µm–2 µm), nano-protist (2 µm–20 µm), and micro-protist (20 µm–200 µm), in the euphotic zone of the South China Sea. The trophic mode compositions of protist communities varied significantly across three size fractions, characterized by a substantial prevalence of parasitic pico-protists (40% amplicon sequence variants) and a greater predominance of mixotrophic taxa within nano- and micro-protist communities. Furthermore, we detected stronger vertical stratification of bacterial and pico-protist communities, corresponding to the wider niche breadth of smaller cells and reliance on passive dispersal. Additionally, both bacterial and protist community assemblies were dominated by stochastic processes. The relative contribution of homogeneous selection in nano-protist community assembly was greater compared to other size fractions, probably related to high relative abundance of mixotrophs. In summary, our results suggest that both cell size and trophic mode affect marine microbial community assembly, and that neither the “size-plasticity” hypothesis nor the “size-dispersal” hypothesis fully matched microbial communities. Our analyses are important for a better understanding of the assemblage processes of marine epipelagic microbial communities and how they will respond to global change. IMPORTANCE Cell size is a key feature that influences microbial biology at both the cellular and community levels. Poorly understood is the extent to which diverse ecological factors influence the assembly of microbial communities of various sizes. Two important hypotheses addressing the mechanisms of biome assembly are “size-plasticity” and “size-dispersal.” Here, we investigated epipelagic microbial communities to reveal differences in the ecological functions of various microbial sizes, to explore the association of ecological processes with niche and cell size, and to expand the current understanding of marine microbial community assemblages and their possible responses to future global change.

This study investigated the level of dissolved heavy metals in the water of Longhu Lake and focused on the speciation, mobility, and risks of heavy metals (Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb) in sediment. The levels of heavy metals in the water were found to be below the thresholds set by the Chinese safe drinking water standard. The highest average percentages of Cr, Ni, Zn, and As were bound with residual fractions, while Pb and Cu were bound with reducible fractions. Additionally, the highest percentage of Cd and Mn was bound to the acid-soluble fraction in the sediment. These findings suggest that Cd, Mn, Pb, and Cu likely originated from anthropogenic sources in the lake. There was a strong correlation between total organic carbon (TOC) and metal fractions in the sediment, indicating that TOC may play a role in transporting heavy metal fractions. Risk assessment code values for Cd and Mn indicated higher risks and mobility, while Ni, Cu, and Zn showed medium risks and mobility for aquatic biota. To mitigate heavy metal contamination, it is recommended to improve monitoring and regulation of urban runoff and inlet areas.

Plastic pollution has become a global environmental problem, and the large number of microorganisms attached to plastic debris in the environment has become a hot topic due to their rapid response to pollutants and environmental changes. In this study, we used high-throughput sequencing to investigate the microbial community structure of and explore the metagenome in the biofilm of two types of plastic debris, polystyrene (PS) and polyethylene terephthalate (PET), and compared them with a water sample collected at the sampling site. The phylum Proteobacteria dominated both the PET and PS samples, at 93.43% and 65.95%, respectively. The metagenome data indicated that the biofilm is enriched with a number of hydrocarbon (petroleum, microplastics, etc.) degrading genes. Our results show that the type of plastic determined the bacterial community structure of the biofilm, while the environment had relatively little effect.

This study aimed to explore the spatial distribution, sources, contamination status, speciation, and risks of vanadium (V) in sediments and water from Yundang Lagoon (YL) at Xiamen in China. The concentration of V in YL water exhibited a similar distribution pattern, with an average concentration lower than the Chinese drinking water limit value. The V content in the sediments of various YL sampling sites varied significantly. The average V concentration in sediments was 108.28 mg/kg, ranging from 77.38 mg/kg to 151.20 mg/kg. Speciation investigations revealed that the largest amount of V was bound in the residual fraction, while the acid-soluble fraction had the lowest concentration in sediments. On average, the residual and acid-soluble fractions were 51.82% (ranging from 16.09% to 76.13%) and 1.22% (ranging from 0.16% to 2.60%), respectively. Enrichment factor values suggested minor anthropogenic enrichment of V in sediments. Correlation analysis indicated a weak correlation between silt and clay, while carbonate and Fe showed significant correlations with total V in sediments. This correlation suggests that concentrations of Fe and carbonate could favour V accumulation in YL sediments. Potential ecological risk values suggested no risk of V to aquatic biota in the study area.

Croakers are an economically important fish species in Nigeria. Croakers are harvested by artisanal and industrial fisheries, providing a significant source of income and livelihood for coastal communities. Yet, human activities pose a significant threat to the survival of croakers in Nigeria. This study aims to evaluate the sustainability of croakers in the coastal waters of Lagos, Nigeria. The study also examines stakeholders' perceptions of EcosystemBased Fisheries Management (EBFM) as a tool for sustainable fisheries management in Nigeria. Questionnaires are used to collect data, and the Multidimensional Scaling Tool "Rapfish" is used to assess the sustainability level of croakers in three study areas. The results indicate that stakeholders have a positive attitude toward implementing EBFM. The sustainability analysis indicates degrees of sustainability of croakers at the boundary of being "less sustainable". Specifically, the sustainability scores along the five dimensions analyzed are Ecological sustainability (55.69 %), economic (56.35 %), ethical (54.02 %), social (42.31 %), and technological sustainability (57.51 %). Based on these findings, the study derives several policy recommendations to improve the sustainability of croakers in Nigeria.

A small pigmented flagellate, Micromonas, is prevalently distributed in coastal and pelagic waters. However, there have been few studies conducted to quantify their abundance in the marginal seas of the Northwest Pacific Ocean. In this study, we used fluorescent in situ hybridization with tyramide signal amplification (TSA-FISH) to reveal the spatial distribution of Micromonas in the northern South China Sea (SCS). On average, the abundance of Micromonas was 317 cells mL(-1), with the average proportions in the nanoflagellates (NF) and photosynthetic picoeukaryotes (PPE) communities being 10.94% and 15.39%, respectively. This indicates a wide distribution and dominance of this genus in the studied area. The relationships between Micromonas abundance and various environmental factors suggested that biotic correlations play more important roles than physicochemical filtering on Micromonas assemblage. This may indicate a broad environmental adaptation spectrum of this genus through its flexibility in terms of resource acquisition strategies. In summary, this study provides insight into the spatial distribution pattern of Micromonas and highlights its crucial contribution to the composition of NFs and PPE communities, which rely on biological interaction to respond to the changing environmental conditions in the northern SCS.