Open research questions in Marine and coastal plant biology

What the literature leaves open

• The difficulty of restoring charophyte habitats due to anthropogenic activity. The need to identify the most suitable substrate for C. tomentosa transplants. The challenge of understanding the complex interactions between sediment characteristics and C. tomentosa growth.

  Sediment characteristics affect thallus and rhizoid growth of the charophyte Chara tomentosa L. · 2026 · DOI

• investigating the effects of sediment characteristics on Chara tomentosa growth in different environments, - examining the long-term effects of sediment sand additions on C. tomentosa growth, - studying the impact of other sediment properties on C. tomentosa growth

  Sediment characteristics affect thallus and rhizoid growth of the charophyte Chara tomentosa L. · 2026 · DOI

• The limited spatial extent of target species in aerial imagery. The class imbalance in the dataset, with Spartina pixels occupying approximately 24.8% of the data. The need to mitigate spatial autocorrelation between training and validation samples. The challenge of fusing heterogeneous modalities, such as elevation data, into a photographically pre-trained encoder.

  Training strategy over architecture: A systematic ablation study for Spartina detection from aerial imagery with small geospatial datasets · 2026 · DOI

• The study uses a small geospatial dataset, - The five-fold estimate may be optimistic for genuinely new sites, - Independent field validation is still needed, - The study only evaluates three segmentation architectures

  Training strategy over architecture: A systematic ablation study for Spartina detection from aerial imagery with small geospatial datasets · 2026 · DOI

• methodological limitations due to logistical constraints, - gas flux measurements are limited in temporal replication, - below 50 cm depth a coarser core interval was used

  Landscape- and site-scale spatial variability of blue carbon stocks and fluxes in tropical seagrass meadows · 2026 · DOI

• The variability in current blue carbon stock and flux estimates is high, particularly at landscape scale. There is a need for evaluating blue carbon at spatial scales that are both locally robust and globally relevant.

  Landscape- and site-scale spatial variability of blue carbon stocks and fluxes in tropical seagrass meadows · 2026 · DOI

• Abstract The porewater‐surface water interface influences methane (CH 4 ) dynamics in mixed seagrass‐macroalgae ecosystems, but the mechanisms governing methanogenesis, oxidation suppression, and emission amplification remain poorly understood.

  Porewater‐Surface Water Interface Mediates Methanogenesis, Oxidation, and Large Methane Emissions in Mixed Seagrass‐Macroalgae Ecosystems · 2026 · DOI

• Their high flexibility and dynamic motion causes time‐varying drag forces, but the underlying mechanisms remain poorly understood.

  In Situ Measurements of Giant Kelp (M. pyrifera) Motion · 2026 · DOI

• Although they share a common origin with modern-day plants and display complex multicellular development, comprehensive genome data from the most highly evolved red algal groups remain scarce.

  The expanded Bostrychia moritziana genome unveils evolution in the most diverse and complex order of red algae · 2025 · DOI

• We will in this contribution summarise our current understanding of photosynthetic carbon assimilation of submerged marine photoautotrophs, and in particular how their ‘biophysical’ CCMs differ from the ‘biochemical’ CCMs of terrestrial C4 and Crassulacean Acid Metabolism (CAM) plants (for which there is very limited evidence in cyanobacteria, algae and seagrasses).

  Inorganic Carbon Acquisition and Photosynthetic Metabolism in Marine Photoautotrophs: A Summary · 2025 · DOI

• Early kelps were possibly grazed upon by mammals like desmostylians, but fossil evidence of the complex ecological interactions known from extant kelp forests is lacking.

  Early Oligocene kelp holdfasts and stepwise evolution of the kelp ecosystem in the North Pacific · 2024 · DOI

• However, the regulatory mechanisms governing the initiation of this stage by changes in environmental conditions are not well understood.

  H2O2 drives the transition from conchocelis to conchosporangia in the red alga Pyropia haitanensis with promotion facilitated by 1-Aminocyclopropane-1-carboxylic acid · 2024 · DOI

• It remains unclear how eutrophication influences the composition and function of microbial communities associated with different parts of seagrass.

  Impacts of eutrophication on microbial community structure in sediment, seawater, and phyllosphere of seagrass ecosystems · 2024 · DOI

• Efficient nitrogen (N) cycling and uptake are essential to maintain plant productivity, but the effects of OA on N transformations in these systems are poorly understood.

  Accelerated nitrogen cycling on Mediterranean seagrass leaves at volcanic CO2 vents · 2024 · DOI

• Theory predicts that spatial modular networks contain the propagation of local disturbances, but field experimental tests of this hypothesis are lacking.

  Modularity buffers the spread of spatial perturbations in macroalgal networks · 2024 · DOI

• Although the large concentration of plants and algae in marine coastal environments provides ample habitat and reliable resources for microbial communities, the role of the microbiome in host-microbe nitrogen cycling remains poorly understood.

  Ammonification by kelp associated microbes increases ammonium availability · 2024 · DOI

• Further studies should investigate the effects of other factors, such as water temperature and nutrient availability, on sea urchin feeding behavior. Research should focus on developing effective conservation strategies to mitigate kelp forest degradation.

  When Sea Urchins Dine: The Roles of Friends, Food and Fear and Implications to Kelp Forest Conservation · 2026 · DOI

• There is a need to understand the behavioral drivers of sea urchin overgrazing in kelp forests. Previous studies have not fully investigated the effects of group size, diet composition, and predator cues on sea urchin feeding behavior.

  When Sea Urchins Dine: The Roles of Friends, Food and Fear and Implications to Kelp Forest Conservation · 2026 · DOI

• Integration of scientific knowledge into coastal policies through a Decision Support System (DSS) is needed to foster adoption of adaptive strategies reconciling environmental protection with tourism and local economies.

  Characterization and Management of Posidonia oceanica Banquettes as Nature-Based Solutions for Coastal Resilience · 2026 · DOI

• There is a lack of understanding of the persistence of kelp forests under accelerating ocean warming and intensifying marine heatwaves. There is a need for comprehensive, long-term studies with consistent datasets to capture trends in species presence and ecological persistence.

  Centennial persistence of kelp forests on the West Coast of Vancouver Island, Canada · 2026 · DOI

• There is a limited understanding of the reproduction and early life-cycle biology of D. potatorum. There is a lack of scalable nursery techniques for D. potatorum.

  Early life-cycle biology and nursery suitability of the southern bull kelp (Durvillaea potatorum) · 2026 · DOI

• The research gap lies in the limited understanding of the impact of nutrient availability on seagrass ecosystems. The study aims to address this gap by investigating the spatio-temporal dynamics of volcanic sediment nutrients and their association with the morpho-physiological plasticity of E. acoroides.

  Spatio-Temporal Dynamics of Volcanic Sediment Nutrients and their Association of Morpho-Physiological Plasticity of Enhalus acoroides in the Small Islands of Wallacea: A Case Study from Ternate Island, Indonesia · 2026 · DOI

• The paper identifies that small volcanic islands require holistic management approaches to maintain seagrass ecosystem sustainability, but no specific monitoring protocol for detecting critical nutrient thresholds (NO3- and TP levels) or corresponding morphometric warning indicators for E. acoroides has been proposed or validated.

  Spatio-Temporal Dynamics of Volcanic Sediment Nutrients and their Association of Morpho-Physiological Plasticity of Enhalus acoroides in the Small Islands of Wallacea: A Case Study from Ternate Island, Indonesia · 2026 · DOI

• Future research should investigate the long-term effects of a plant-based diet on red knots. Future research should examine the ability of other species to adjust to a plant-based diet.

  Molluscivorous red knots rapidly adjust to a plant diet · 2026 · DOI

• There is a lack of understanding of the ability of red knots to adjust to a plant-based diet. The study aims to address this gap by investigating the ability of red knots to live on plant material.

  Molluscivorous red knots rapidly adjust to a plant diet · 2026 · DOI

Most-cited papers in Marine and coastal plant biology

• A Global Crisis for Seagrass Ecosystems · BioScience · 2006 · 2,485 citations
• Threats and knowledge gaps for ecosystem services provided by kelp forests: a northeast Atlantic perspective · Ecology and Evolution · 2013 · 483 citations
• Global challenges for seagrass conservation · AMBIO · 2018 · 322 citations
• The Central Role of Dispersal in the Maintenance and Persistence of Seagrass Populations · BioScience · 2012 · 299 citations
• The value of ecosystem services in global marine kelp forests · Nature Communications · 2023 · 265 citations
• The Influence of Marine bottom Communities on the Depositional Environment of Sediments · The Journal of Geology · 1958 · 214 citations
• Climate change impact on seaweed meadow distribution in the North Atlantic rocky intertidal · Ecology and Evolution · 2013 · 198 citations
• The future of the northeast Atlantic benthic flora in a high CO2 world · Ecology and Evolution · 2014 · 189 citations
• Warming off southwestern Japan linked to distributional shifts of subtidal canopy‐forming seaweeds · Ecology and Evolution · 2012 · 169 citations
• Ecosystem Services Provided by Seaweeds · Hydrobiology · 2023 · 161 citations

Most recent work

• Extreme marine heatwaves drive divergent kelp forest trajectories and alternative stable states · Frontiers in Marine Science · 2026
• A catastrophic marine mortality event caused by a complex algal bloom including the brevetoxin producer Karenia cristata · Nature Ecology & Evolution · 2026
• Response of Early Life‐Stages of Forest‐Forming Seaweeds From Warm‐Edge and Central Populations to Marine Heatwaves · Ecology and Evolution · 2026
• Spatiotemporal Dynamics of Micropropagules in Seawater During the 2020 Green Tide Outbreak in the Southern Yellow Sea · Biology · 2026
• Impact of macroalgae farming on the carbonate system and biogenic sulfur dynamics in Sansha Bay, China · Marine Pollution Bulletin · 2026
• Ocean warming indirectly affects seagrass performance through effects on sediment microbial communities · New Phytologist · 2026
• Mass flowering of the seagrass Posidonia oceanica after 2022 record-breaking marine heatwaves, a Pan-Mediterranean study · Communications Earth & Environment · 2026
• Global high-resolution mapping of seagrass to support conservation · Nature · 2026
• Spatial and Temporal Patterns in Phenology, Fecundity, and Fertility for Spartina alterniflora in Coastal Georgia · Journal of Coastal Research · 2026
• Marine epiphytic diatoms: a review of environmental controls and ecosystem roles · Frontiers in Marine Science · 2026

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