Topic Editors

Laboratory of Environmental Quality and Geospatial Applications, Department of Marine Sciences, University of the Aegean, GR-81100 Mytilene, Lesvos, Greece
Dr. Maurizio Azzaro
CNR-IAMC, National Research Council, Institute for Coastal Marine Environment, Spianata S. Raineri, 86, 98122 Messina, Italy

Marine Ecology, Environmental Stress and Management

Abstract submission deadline
30 April 2024
Manuscript submission deadline
30 August 2024
Viewed by
15890

Topic Information

Dear Colleagues,

Scientific interest in marine life began in the first decades of the 19th century. Initially, research almost exclusively focussed on the exploration and description of marine organisms. However, it became apparent that the perception of biogeochemical processes required an understanding of the relationships between biological communities and the abiotic environment, as well as between organisms. This led to the emergence of the field of marine ecology, which embraced diverse scientific disciplines. Through this, researchers soon developed knowledge on trophic webs, the production and consumption of organic matter, the flow of energy and biomass through the ecosystem, and the identification of limiting factors. These developments produced revolutionary scientific concepts and encouraged the generation of new methods in fieldwork, the laboratory, and data analysis. Marine ecology, beyond purely scientific interest, is now recognized as an applied scientific field. Applied marine ecology provides a scientific background for marine environmental protection and conservation policies. In addition to the identification and quantification of the effects of pollution, it is an indispensable tool for coastal management and marine spatial planning, and studying various aspects of climate change. Finally, and importantly, marine ecology is an indespensible contribution to environmental impact assessment studies.

This publication welcomes original research articles or reviews on all aspects of marine ecological communities, with emphasis on the links between different ecological groups. Biogeochemical marine ecological processes, as well as the flow of energy and matter through marine ecosystems, are also within the scope of this issue. We are especially interested in manuscripts on ecosystem stress due to species invasions, climate change, and forms of pollution, with a focus on emerging pollutants. We also welcome work that suggests ways to mitigate environmental impacts through management and the improvement of environmental quality, as well as experimental research and data-analyses on environmental quality assessment methodologies.

Prof. Dr. Michael Karydis
Dr. Maurizio Azzaro
Topic Editors

Keywords

  • marine communities
  • benthic biota
  • plankton communities
  • climate change
  • emerging pollutants
  • species invasions
  • impact assessment
  • data analysis

Participating Journals

Journal Name Impact Factor CiteScore Launched Year First Decision (median) APC
Diversity
diversity
2.4 3.1 2009 17.8 Days CHF 2600 Submit
Ecologies
ecologies
- - 2020 19.8 Days CHF 1000 Submit
Journal of Marine Science and Engineering
jmse
2.9 3.7 2013 15.4 Days CHF 2600 Submit
Sustainability
sustainability
3.9 5.8 2009 18.8 Days CHF 2400 Submit
Water
water
3.4 5.5 2009 16.5 Days CHF 2600 Submit

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Published Papers (12 papers)

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10 pages, 4108 KiB  
Article
Polluted Rivers—A Case Study in Porto, Portugal
by Patrícia Lemos, Paulo Silva, Cátia A. Sousa and Abel J. Duarte
Ecologies 2024, 5(2), 188-197; https://doi.org/10.3390/ecologies5020012 - 06 Apr 2024
Viewed by 424
Abstract
River contamination by microorganisms, or another chemical source, poses a serious threat to both the environment and public health. Taking immediate and appropriate actions is essential to mitigate the contamination and prevent further spread. As such, regular monitoring of these pollution agents is [...] Read more.
River contamination by microorganisms, or another chemical source, poses a serious threat to both the environment and public health. Taking immediate and appropriate actions is essential to mitigate the contamination and prevent further spread. As such, regular monitoring of these pollution agents is essential to act in time and control its minor extension. However, there is a lack of commitment to this emergent concern and respective actions around the world. This work aims to study the contamination of a Portuguese river (Tinto River) within Porto city (a highly populated urban area) regarding the total aerobic microorganisms, coliforms, and Enterococcus (as colony-forming units (CFUs) using specific solid culture media) and total organic matter (TOC). Different locations were considered along the Tinto River course (i.e., 14 locations within 11 km) and samples were collected on distinct days throughout September 2022. The overall results showed microbial contamination of aerobic microorganisms (up to 2 × 105 CFU/100 mL), total coliforms (up to 7 × 104 CFU/100 mL), Escherichia coli (up to 9 × 103 CFU/100 mL), and Enterococcus (up to 8 × 103 CFU/100 mL). The results also surpassed the maximum recommended values (MRVs) described in Portuguese decree-law no. 236/98 for irrigation waters. Moreover, TOC was found in a range of 4.54 mg/L to 57.2 mg/L. This work highlights the dangerous microbial contamination and higher amount of organic matter than would be expected for a surface water resource. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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14 pages, 2407 KiB  
Article
Mass Mortality Event of Mediterranean Mussels (Mytilus galloprovincialis) in the Middle Adriatic: Potential Implications of the Climate Crisis for Marine Ecosystems
by Luca Bracchetti, Martina Capriotti, Massimiliano Fazzini, Paolo Cocci and Francesco Alessandro Palermo
Diversity 2024, 16(3), 130; https://doi.org/10.3390/d16030130 - 20 Feb 2024
Viewed by 1041
Abstract
The effects of the climate crisis are affecting ecosystems at different scales and magnitudes. This paper focuses on a massive Mediterranean mussel die-off observed along the middle Italian Adriatic coast in the summer of 2022. We considered the possible environmental causes of this [...] Read more.
The effects of the climate crisis are affecting ecosystems at different scales and magnitudes. This paper focuses on a massive Mediterranean mussel die-off observed along the middle Italian Adriatic coast in the summer of 2022. We considered the possible environmental causes of this phenomenon and carried out a climatic analysis of the last decade. We performed field surveys in different locations along a 16 km coastal stretch from Martinsicuro (TE) in the south, to Grottammare (AP) in the north. The study area includes two marine Sites of Community Importance under the European Natura 2000 network. The die-off of the mussels was observed in practically all the natural mussel beds colonizing the study area. As sessile filter-feeding organisms inhabiting the intertidal zone, mussels are highly exposed to variations in environmental conditions such as temperature and nutrient load. We discuss the possible causes of this die-off, proposing that high temperature and the scarce availability of food acted simultaneously as stress factors, generating local unsustainable living conditions for this species. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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25 pages, 698 KiB  
Review
Alternate Stable States Theory: Critical Evaluation and Relevance to Marine Conservation
by Jean-Marc Guarini and Jennifer Coston-Guarini
J. Mar. Sci. Eng. 2024, 12(2), 261; https://doi.org/10.3390/jmse12020261 - 31 Jan 2024
Viewed by 911
Abstract
In their 2023 book, “The Blue Compendium: From Knowledge to Action for a Sustainable Ocean Economy”, Lubchenko and Haugan invoked alternate stable (AS) states marginally as an undesired consequence of sources of disturbance on populations, communities and ecosystems. They did not provide detailed [...] Read more.
In their 2023 book, “The Blue Compendium: From Knowledge to Action for a Sustainable Ocean Economy”, Lubchenko and Haugan invoked alternate stable (AS) states marginally as an undesired consequence of sources of disturbance on populations, communities and ecosystems. They did not provide detailed arguments, but considered the existence of AS states as a given. Conversely, May, in his 1977 Nature article, pointed out that, when applied to systems that are complex, “the [AS states] theory remains largely metaphorical”. This is the starting point of this critical review, which aims to re-examine the general theory behind AS states in ecological systems and its applications to marine ecology and conservation. The focus is first on theory, taking as examples communities that sustain competition and studying the relative importance of the fluxes of individuals between simple low-dimension, interconnected systems. We find that a minimal formulation of fluxes is sufficient to obtain a set of non-null multiple stable (MS) states and to trigger shifts between AS states when fluxes become large enough. This provides new insights into the theory of rescue and mass effects by distinguishing them through a threshold at which the system dynamics shift from one stable equilibrium to another. Then, we consider how the theoretical framework of AS states has been applied in marine environments. It appears that many applications have confounded shifts between AS states and changes in the structure of systems, particularly when the complexity of the systems increases. The main difficulty for any application remains that the concepts of MS and AS states can only be established and validated for low-dimension systems and simplified experiments. This is because the mathematical properties of models that describe large-dimension, complex systems deviate from the observed characteristics of their real-world counterparts. There are many intriguing scientific challenges around the plausible shifts between AS states, but a deeper understanding and characterization of their occurrence in nature would require a significant investment in modeling to formulate predictive ecosystem models. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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19 pages, 6426 KiB  
Article
Diel Variation in Phytoplankton Biomass Driven by Hydrological Factors at Three Coastal Monitoring Buoy Stations in the Taiwan Strait
by Cun Jia, Lei Wang, Youquan Zhang, Meihui Lin, Yan Wan, Xiwu Zhou, Chunsheng Jing and Xiaogang Guo
J. Mar. Sci. Eng. 2023, 11(12), 2252; https://doi.org/10.3390/jmse11122252 - 28 Nov 2023
Cited by 1 | Viewed by 641
Abstract
To investigate the diurnal variation in phytoplankton biomass and its regulating factors during the diurnal cycle, we conducted in situ observations in June 2018 at three buoy stations, including Douwei Buoy Station, Minjiang Estuary Buoy Station, and Huangqi Buoy Station on the western [...] Read more.
To investigate the diurnal variation in phytoplankton biomass and its regulating factors during the diurnal cycle, we conducted in situ observations in June 2018 at three buoy stations, including Douwei Buoy Station, Minjiang Estuary Buoy Station, and Huangqi Buoy Station on the western side of the Taiwan Strait. The calibration of buoy sensor data, including temperature, salinity, dissolved oxygen, pH, chlorophyll, and phycoerythrin, was conducted simultaneously. In addition, water sampling was conducted to measure chlorophyll a and phycoerythrin concentrations at hourly time intervals. The results showed that the 24 h cumulative chlorophyll a concentration order for the buoys was Minjiang Estuary (10.280 μg/L) > Huangqi (7.411 μg/L) > Douwei (4.124 μg/L). The Minjiang Estuary had a lower nighttime biomass proportion than Douwei and Huangqi. The diurnal variation in phytoplankton was jointly regulated by water masses, tides, and light. There were three response patterns, including the “light trumps tidal influences” pattern at Douwei, the “Low-tide, High-biomass” pattern at Minjiang Estuary, and the “High-tide, High-biomass” pattern at Huangqi. The prediction of algal blooms and hypoxia using buoy monitoring needs to be based on seasonal water mass background and tidal influence. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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20 pages, 17448 KiB  
Article
A Preliminary Snapshot Investigation of the Marine Soundscape for Malta: A Steppingstone towards Achieving ‘Good Ecological Status’
by Julia Micallef Filletti, Adam Gauci, Alan Deidun, Giorgio Riccobene and Salvatore Viola
J. Mar. Sci. Eng. 2023, 11(11), 2163; https://doi.org/10.3390/jmse11112163 - 13 Nov 2023
Viewed by 1252
Abstract
The ever-accelerating rate of research focusing on the issue of underwater noise pollution, particularly concerning low-frequency, continuous noise, has steadily been unveiling the myriad of detrimental ecological implications caused to marine life. Despite this, many European Member States, such as Malta, still lack [...] Read more.
The ever-accelerating rate of research focusing on the issue of underwater noise pollution, particularly concerning low-frequency, continuous noise, has steadily been unveiling the myriad of detrimental ecological implications caused to marine life. Despite this, many European Member States, such as Malta, still lack solid monitoring and regulatory frameworks aimed at characterising and improving the state of the marine acoustic environment and achieving ‘Good Ecological Status’ in accordance with the Marine Strategy Framework Directive. This shortcoming is directly reflected in the complete absence of baseline information covering the quality of the national soundscape. This paper aims to serve as a preliminary investigation into continuous underwater noise generation within Maltese waters, focusing on two sites characterised by heavy marine activity: Ċirkewwa and the Grand Harbour. Digital signal processing software packages (dBWav version 1.3.4) were used to extract and analyse sound pressure levels from in situ recorded audio files. Further statistical analysis was also carried out so as to evaluate the resultant snapshot of the baseline marine soundscapes at both sites. Furthermore, AIS data were used to tentatively identify the identifiable sources of underwater noise pollution. Given the current information lacuna revolving around the issue of underwater noise pollution in Malta, this paper may serve as a pilot study, with the aim of bridging this knowledge gap and forming the basis of future national research for Maltese marine conservation. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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19 pages, 2293 KiB  
Article
Beyond the Ecological Boundary: A Quasi-Natural Experiment on the Impact of National Marine Parks on Eco-Efficiency in Coastal Cities
by Xiao Zhang and Di Wang
Sustainability 2023, 15(20), 14856; https://doi.org/10.3390/su152014856 - 13 Oct 2023
Cited by 1 | Viewed by 664
Abstract
National marine parks (NMPs) are a crucial form of marine protected areas that serve an essential function in safeguarding marine ecosystems and the related inland urban ecosystems. Though 30 coastal cities in China have established NMPs, little is known about the ecological benefits [...] Read more.
National marine parks (NMPs) are a crucial form of marine protected areas that serve an essential function in safeguarding marine ecosystems and the related inland urban ecosystems. Though 30 coastal cities in China have established NMPs, little is known about the ecological benefits national marine parks contribute to surrounding areas. This study takes China’s coastal cities as an example and employs a multi-period DID model to investigate how eco-efficiency responds to the establishment of national marine parks, based on panel data from 2003 to 2020. The results show that the establishment of NMPs contributed to a 3.87% enhancement in the eco-efficiency of coastal cities. This finding remains robust after a series of robustness tests such as PSM-DID. In addition, significant heterogeneities are captured, with NMPs exhibiting a more substantial enhancement effect for cities along the East China Sea and South China Sea. NMPs with a large area increased the eco-efficiency of coastal cities by 5.18%, but small-area NMPs failed the significance test. A mechanism analysis further reveals that NMPs could improve the eco-efficiency of coastal cities by optimizing the industrial structure, enlivening the local economy, and inhibiting sewage pollution behaviors. This study provides evidence of the impact of NMPs on local eco-efficiency in developing countries. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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18 pages, 12242 KiB  
Article
Assessment of Diversity of Marine Organisms among Natural and Transplanted Seagrass Meadows
by Jatdilok Titioatchasai, Komwit Surachat, Ekkalak Rattanachot, Piyalap Tuntiprapas and Jaruwan Mayakun
J. Mar. Sci. Eng. 2023, 11(10), 1928; https://doi.org/10.3390/jmse11101928 - 06 Oct 2023
Viewed by 1008
Abstract
Seagrass ecosystems have been declining, and restorations are conducted in many parts of the world to compensate for habitat loss and restore the ecosystem services seagrasses provide. Assessment of transplantation success requires the monitoring of the level of biodiversity between the donor and [...] Read more.
Seagrass ecosystems have been declining, and restorations are conducted in many parts of the world to compensate for habitat loss and restore the ecosystem services seagrasses provide. Assessment of transplantation success requires the monitoring of the level of biodiversity between the donor and transplanted sites. In this study, we assessed a seagrass ecosystem after restoration in terms of the diversity of marine organisms using environmental DNA (eDNA) to compare four sites: (1) bare sand, (2) a natural meadow of Cymodocea serrulata, (3) a natural meadow of Halophila ovalis, and (4) a transplanted seagrass meadow. The results showed the presence of 3 domains, 34 phyla, 59 classes, 92 orders, 155 families, 156 genera, and 121 species. Proteobacteria, Actinobacteria, Cyanobacteria, and Bacteroidetes were the dominant bacterial phyla. Among eukaryotes, Phragmoplastophyta/Charophyta (epiphytes), Ascomycota (fungi), Cnidaria (jelly fish), and Arthropoda (Crabs and bivalves) were the dominant phyla. Dugong tails and commercial species (sea cucumber, dog conch, and swimming crab) have been observed in both the natural and transplanted meadows. Relative abundance among the four sites was significantly different. There were no differences in species richness and evenness between the four sites and no differences in species richness and evenness between the natural meadows and the transplanted seagrass meadow. It is possible that transplanted seagrass meadow can be successfully restored and established and can provide habitat for fauna and microbes. Additionally, fauna are not limited in their capacity to move between the natural and transplanted habitats. This study provides an assessment of biodiversity of restored seagrass patches and a better understanding of a seagrass ecosystem after restoration. However, to assess seagrass ecosystem services after restoration and the success of restoration actions, long-term monitoring of marine organism diversity and additional assessments are needed. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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15 pages, 3542 KiB  
Article
Spatial Differentiation Assessment of the Vulnerability of Marine Protected Areas to Oil Spill Stress in the Bohai Sea
by Yebao Wang, Cheng Tang, Peipei Du, Baijing Liu, Yanfang Li and Chuntao Chen
J. Mar. Sci. Eng. 2023, 11(10), 1877; https://doi.org/10.3390/jmse11101877 - 27 Sep 2023
Cited by 1 | Viewed by 727
Abstract
Marine protected areas (MPAs) are pivotal in safeguarding and preserving global ocean ecosystems. However, oil spills exert both discernible and evident impacts on marine ecosystems and the biodiversity of MPAs. In this research, an environmental model for assessing vulnerability to oil spills was [...] Read more.
Marine protected areas (MPAs) are pivotal in safeguarding and preserving global ocean ecosystems. However, oil spills exert both discernible and evident impacts on marine ecosystems and the biodiversity of MPAs. In this research, an environmental model for assessing vulnerability to oil spills was constructed, which amalgamates diverse indicators pertaining to pressure, state, and response capabilities into a unified index. This integration was achieved through the utilization of a geographic information system (GIS) and the analytic hierarchy process (AHP). For clarity, the Bohai Sea was segmented into seven distinct response zones. The study’s results underscore the substantial spatial disparities in vulnerability when these zones are exposed to oil spills. Notably, zone 6 displayed markedly heightened vulnerability compared to the other zones, while MPAs exhibiting relatively low to extremely low vulnerabilities were primarily situated in the northern sector of zone 7 and across zone 5. This study employed a quantitative vulnerability analysis to offer valuable perspectives on the repercussions of oil spill incidents on MPAs. This emphasizes the necessity of enhancing adaptability to minimize vulnerability, benefiting MPA stakeholders susceptible to the risks associated with oil spills. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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15 pages, 3774 KiB  
Article
Three-Dimensional-Printed Coral-like Structures as a Habitat for Reef Fish
by Asa Oren, Ofer Berman, Reem Neri, Ezri Tarazi, Haim Parnas, Offri Lotan, Majeed Zoabi, Noam Josef and Nadav Shashar
J. Mar. Sci. Eng. 2023, 11(4), 882; https://doi.org/10.3390/jmse11040882 - 21 Apr 2023
Cited by 3 | Viewed by 2236
Abstract
Coral reefs are three-dimensional biogenic structures that provide habitat for plenty of marine organisms; yet, coral reefs are deteriorating worldwide. Hence, it is essential to identify suitable substitutes for such coral services. This study examines reef fishes’ behavior and reactions to three-dimensional-printed (3DP) [...] Read more.
Coral reefs are three-dimensional biogenic structures that provide habitat for plenty of marine organisms; yet, coral reefs are deteriorating worldwide. Hence, it is essential to identify suitable substitutes for such coral services. This study examines reef fishes’ behavior and reactions to three-dimensional-printed (3DP) corals based on scanned Stylophora pistillata, as well as modified 3DP models. In particular, fishes’ unresponsiveness to the color, shape, morphology, and material of 3DP models both in vitro and in situ experiments was investigated. Coral reef fishes responded to the 3DP corals and demonstrated their usage in a range of services. Moreover, a greater number of fish species interacted more with 3DP models than they did with live corals. Furthermore, specific reef fish species, such as Sea Goldies (Pseudanthias squamipinnis), showed a preference for specific 3DP coral color, and other species demonstrated preferences for specific 3DP model shapes. The current study results show that three-dimensional-printed coral models can substitute for live corals for certain types of reef fish services. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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17 pages, 3305 KiB  
Article
Unravelling Nutrients and Carbon Interactions in an Urban Coastal Water during Algal Bloom Period in Zhanjiang Bay, China
by Jibiao Zhang, Miaojian Fu, Peng Zhang, Dong Sun and Demeng Peng
Water 2023, 15(5), 900; https://doi.org/10.3390/w15050900 - 26 Feb 2023
Cited by 3 | Viewed by 1944
Abstract
Nutrients and carbon play important roles in algal bloom and development. However, nutrients and carbon interactions in the period of the spring algal bloom are not well understood. The aim of this study is to explore the nutrients and carbon interactions in the [...] Read more.
Nutrients and carbon play important roles in algal bloom and development. However, nutrients and carbon interactions in the period of the spring algal bloom are not well understood. The aim of this study is to explore the nutrients and carbon interactions in the period of the spring algal bloom covering an urban Jinsha Bay (JSB) coastal water in Zhanjiang Bay (South China Sea) using in situ multidiscipline observation. The results showed that the average concentration of total nitrogen (TN), total phosphorus (TP), and dissolved silicon (DSi) was 97.79 ± 26.31 μmol/L, 12.84 ± 4.48 μmol/L, and 16.29 ± 4.00 μmol/L in coastal water, respectively. Moreover, the average concentration of total dissolved carbon (TDC), dissolved inorganic carbon (DIC) and organic carbon (DOC) in JSB was 2187.43 ± 195.92 μmol/L, 1516.25 ± 133.24 μmol/L, and 671.13 ± 150.81 μmol/L, respectively. Furthermore, the main dominant species were Phaeocystis globosa and Nitzschia closterium during the spring algal bloom. Additionally, the correlation analysis showed salinity (S) was significantly negatively correlated with nutrients, indicating that nutrients derived from land-based sources sustained spring algal bloom development. However, as the major fraction of TDC, DIC was significantly positively correlated with S, which was mainly derived from marine sources. Besides, the algal density showed a significant positive correlation with temperature (T) (p < 0.001) and dissolved oxygen (DO) (p < 0.001), but a significant negative correlation with DIC (p < 0.05), suggesting that spring algal blooms may be simulated by water T increase, and then large amounts of DIC and nutrients were adsorbed, accompanying DO release through photosynthesis in coastal water. This study revealed nutrients and carbon interactions in the spring algal bloom of urban eutrophic coastal water, which has implications for understanding the nutrients and carbon biogeochemical cycle and algal bloom mitigation under climate change and anthropogenic pressures in the future. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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16 pages, 4048 KiB  
Article
A High Abundance of Holothuria (Halodeima) atra (Holothuroidea Aspidochirotida) in a Halimeda Dominated Habitat
by Vanyarat Kongsap, Ekkalak Rattanachot, Anchana Prathep, Witthaya Buaphol and Jaruwan Mayakun
J. Mar. Sci. Eng. 2023, 11(2), 451; https://doi.org/10.3390/jmse11020451 - 18 Feb 2023
Cited by 1 | Viewed by 1606
Abstract
High-value sea cucumber species are overexploited, and the focus of fishing has shifted to low-value species, e.g., Holothuria (Halodeima) atra. In this study, the population of H. atra was investigated in three different habitats: a seagrass habitat, a seaweed habitat, and bare sand, [...] Read more.
High-value sea cucumber species are overexploited, and the focus of fishing has shifted to low-value species, e.g., Holothuria (Halodeima) atra. In this study, the population of H. atra was investigated in three different habitats: a seagrass habitat, a seaweed habitat, and bare sand, at an intertidal zone of Lidee Island, Mu Ko Phetra National Park, Satun Province, Thailand. The habitat type was the predictor which had a significant impact on the density and frequency distribution of the body length of H. atra individuals. H. atra was only found in the seaweed and seagrass habitats. The highest density of this species, 91.1 ± 9.6 inds 100 m−2, was found in the seaweed habitat. The frequency distribution of the body length of H. atra individuals in the seagrass habitat showed no significant change throughout the study period, but the mode of the length frequency distribution in the seaweed habitat gradually rose from 9 to 22 cm from January−September 2019. Asexual reproduction was the major source of recruitment. The occurrence of recently fissioned individuals was slightly higher in the seaweed habitat than in the seagrass habitat (6.0 ± 1.1% and 2.2 ± 0.6%, respectively). This study showed that H. atra was most abundant in the seaweed habitat, which is likely because of the greater availability in this habitat of food sources, microhabitats, and protection against sun irradiance, desiccation, and stress during low tides. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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14 pages, 4455 KiB  
Article
Strong Genetic Structure and Limited Gene Flow among Populations of the Tropical Seagrass Thalassia hemprichii in the Philippines
by Yuichi Nakajima, Yu Matsuki, Miguel D. Fortes, Wilfredo H. Uy, Wilfredo L. Campos, Kazuo Nadaoka and Chunlan Lian
J. Mar. Sci. Eng. 2023, 11(2), 356; https://doi.org/10.3390/jmse11020356 - 05 Feb 2023
Cited by 1 | Viewed by 2355
Abstract
Seagrasses are marine angiosperms, and seagrass beds maintain the species diversity of tropical and subtropical coastal ecosystems. For proper understanding, management and conservation of coastal ecosystems, it is essential to understand seagrass population dynamics. Population genetic studies can cover large geographic scales and [...] Read more.
Seagrasses are marine angiosperms, and seagrass beds maintain the species diversity of tropical and subtropical coastal ecosystems. For proper understanding, management and conservation of coastal ecosystems, it is essential to understand seagrass population dynamics. Population genetic studies can cover large geographic scales and contribute to a comprehensive understanding of reproductive dynamics and potential dispersal among locations. The clonal and genetic diversity and genetic connectivity of Thalassia hemprichii in the Philippines were estimated by a population genetics approach. The geographic scale of this study has a direct distance of approximately 1600 km. Although high clonal diversity was found in some sites (R = 0.07–1.00), both sexual and asexual reproduction generally maintains separate populations. Genetic diversity is not definitely correlated with latitude, and genetic differentiation is significant in all pairs of sites (FST = 0.026–0.744). Complex genetic structure was found in some regions, even at a fine geographic scale. The migration of fruits and seedlings was elucidated as an infrequent and stochastic event. These results suggest the necessity for the conservation of this species due to a deficiency in migrants from external regions. Full article
(This article belongs to the Topic Marine Ecology, Environmental Stress and Management)
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