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BACKGROUND: Glyoxal has been implicated as a significant contributor to the formation of secondary organic aerosols, which play a key role in our ability to estimate the impact of aerosols on climate. Elevated concentrations of glyoxal over open ocean waters suggest that there exists an additional source, different from urban and forest environments, which has yet to be identified. METHODS: Based on mass spectrometric analyses of nascent sea spray aerosols (SSAs) and gas-phase molecules generated during the course of a controlled algal bloom, the work herein suggests that marine microorganisms are capable of excreting toluene in response to environmental stimuli. Additional culture flask experiments demonstrated that pathogenic attack could also serve as a trigger for toluene formation. Using solid-phase microextraction methods, the comparison of samples collected up-channel and over the breaking wave suggests it was transferred across the air-water interface primarily through SSA formation. RESULTS: The presence and then absence of phenylacetic acid in the SSA days prior to the appearance of toluene support previous reports that proposed toluene is produced as a metabolite of phenylalanine through the Shikimate pathway. As a result, once in the atmosphere, toluene is susceptible to oxidation and subsequent degradation into glyoxal. CONCLUSIONS: This work adds to a minimal collection of literature that addresses the primary production of aromatic hydrocarbons from marine microorganisms and provides a potential missing source of glyoxal that should be considered when accounting for its origins in remote ocean regions.

This capstone project is a completed draft of an illustrated field guide of Southern California seaweeds. The purpose of this was to create a region-specific and user-friendly guide for readers to learn about local seaweeds. This was done by collecting life specimens and illustrating them by hand with watercolor. The illustrations were digitized and put into a draft, along with supporting information about each species. The completed draft will be prepared and submitted for publication in print.

Sargassum polycystum is among the seaweed species in the Philippines that are considered coastal waste after drifting on the shorelines. Although there has been a report on the potential of S. polycystum as a biostimulant for certain crops, its utilization as a hydroponic nutrient solution is not yet thoroughly analyzed. Thus, a study utilizes various ratios of S. polycystum seaweed extract (SE) mixed with commercial hydroponic nutrient solution (CHNS) to the growth and yield of green leaf lettuce grown under the Kratky method of hydroponic system. Treatments are 100% CHNS and percentage replacements of CHNS with SE (25%, 50%, and 75%, respectively). The result shows a 10.53% increase in lettuce plant height grown under 25% and 50% SE compared to 100% CHNS. A similar result is also observed in the lettuce leaf width (14.29%), leaf length (7.14%), and plant weight (22.41%). Regarding root length, replacing 50% SE resulted in longer root length (44.83%) and more leaves (10%) compared to lettuce plants grown under 100% CHNS. However, replacement of SE beyond 50% is detrimental to leaf length and comparable to all growth and yield parameters with 100% CHNS. Regarding the return on investment, 50% SE replacement has the highest return of 98.62% compared to 100% CHNS, with 49.87% only for a projected six cropping cycles. Hence, a 50% replacement of CHNS with SE from its recommended rate can be suggested for more profitable production of green leaf lettuce under a hydroponic system. [ABSTRACT FROM AUTHOR]

Green tide area is a crucial indicator for monitoring green tide dynamics. However, scale effects arising from differences in image resolution can lead to estimation errors. Current pixel-level and sub-pixel-level methods often overlook the impact of morphological differences across varying resolutions. To address this, our study examines the influence of morphological diversity on green tide area estimation using GF-1 WFV data and the Virtual-Baseline Floating macroAlgae Height (VB-FAH) index at a 16 m resolution. Green tide patches were categorized into small, medium, and large sizes, and morphological features such as elongation, compactness, convexity, fractal dimension, and morphological complexity were designed and analyzed. Machine learning models, including Extra Trees, LightGBM, and Random Forest, among others, classified medium and large patches into striped and non-striped types, with Extra Trees achieving outstanding performance (accuracy: 0.9844, kappa: 0.9629, F1-score: 0.9844, MIoU: 0.9637). The results highlighted that large patches maintained stable morphological characteristics across resolutions, while small and medium patches were more sensitive to scale, with increased estimation errors at lower resolutions. Striped patches, particularly among medium patches, were more sensitive to scale effects compared to non-striped ones. The study suggests that incorporating morphological features of patches, especially in monitoring striped and small patches, could be a key direction for improving the accuracy of green tide monitoring and dynamic change analysis. [ABSTRACT FROM AUTHOR]

Seaweed is rich in many unique bioactive compounds such as polyphenols and sulfated polysaccharides that are not found in terrestrial plant. The discovery of numerous biological activities from seaweed has made seaweed an attractive functional food source with the potential to be exploited for human health benefits. During food processing and digestion, cell wall polysaccharide and polyphenols commonly interact, and this may influence the nutritional properties of food. Interactions between cell wall polysaccharide and polyphenols in plant-based system has been extensively studied. However, similar interactions in seaweed have received little attention despite the vast disparity between the structural and chemical composition of plant and seaweed cell wall. This poses a challenge in extracting seaweed bioactive compounds with intact biological properties. This review aims to summarize the cell wall polysaccharide and polyphenols present in brown, red and green seaweed, and current knowledge on their potential interactions. Moreover, this review gives an overview of the gut modulation effect of seaweed polysaccharide and polyphenol. Graphical Abtsract: Polysaccharide and polyphenols from algae, the potential interaction between them and their gut modulation effect. [ABSTRACT FROM AUTHOR]

AbstractThe present study aims to investigate the dye decolorization efficiency of the brown seaweed Dictyota bartayresiana against reactive blue 19 (RB19) dye. The process variables namely dye and biosorbent concentration, pH and incubation time were optimized through BBD based RSM for achieving enhanced dye decolorization. The experimental data well fitted into Freundlich isotherm and proving the heterogenous adsorption of RB19. The Temkin and Dubinin – Radushkevich isotherm models showcased the endothermic and chemisorption mediated adsorption of RB19 onto D. bartayresiana. The pseudo second order kinetic model exhibited the chemisorption assisted adsorption and the Weber Morris kinetic model proved that the intra particle diffusion was not the rate limiting step in the adsorption of RB19 onto D. bartayresiana. Thermodynamic studies revealed the spontaneous, feasible and endothermic process of biosorption. Interaction between the dye and the biosorbent was assessed through UV-Vis, FT-IR and SEM which confirmed the process of decolorization. Desorption and regeneration studies revealed that 73% of the dye was desorbed in the first cycle using 0.1 M NaOH as eluent with regeneration efficiency of 68% which reduced in subsequent cycles highlighting the reusability of the biosorbent. Toxicity assessments of untreated and D. bartayresiana treated RB19 dye solution were examined on the microflora, brine shrimp and fenugreek and the results revealed the nontoxic nature of D. bartayresiana treated RB19 solution. Thus, this study provides valuable insights on utilization of D. bartayresiana as an eco-friendly biosorbent for the decolorization of RB19 and affirms its safe use in various biological applications. [ABSTRACT FROM AUTHOR]

AbstractThe exploration of endophytic fungi associated with seaweeds has garnered significant interest due to their crucial ecological functions and potential as sources of valuable bioactive compounds. In this study, we isolated and identified endophytic fungi from the brown seaweed Dictyopteris pacifica, collected from the intertidal zone of Yeongdoek, Gyeongsangbuk-do in Korea. Through morphological examination and molecular phylogenetic analysis using multiple molecular markers, including ITS, LSU, SSU, TEF1, TUB2, and RPB2 sequences, we identified three fungal species not previously recorded in Korea: Emericellopsis fuci, Neoarthrinium lithocarpicola, and Periconia chimonanthi. Detailed descriptions of morphological characteristics and phylogenetic analyses are provided. This study represents the first report of these endophytic fungi isolated from D. pacifica in Korea, thereby enhancing the understanding of the diversity of seaweed-associated endophytic fungi in the region. [ABSTRACT FROM AUTHOR]

Simple Summary: The red macroalgae Acanthophora spicifera (spiny seaweed) is a naturalized alien species at La Paz Bay and appears to tolerate areas with human activity. However, before this study, we were unaware of the type and quantity of hydrozoan epibiont growing on this alga. Therefore, this study aims to examine the community structure of hydrozoan epibionts of A. spicifera in warm and cold seasons. We recorded eleven hydrozoans, of which there are more in summer. This study provides a detailed analysis of the community of hydrozoan epibionts of Acanthophora spicifera in La Paz Bay, Baja California Sur. The investigation was carried out in two season periods, corresponding to the warm and cold seasons on the pier of the Autonomous University of Baja California Sur (UABCS) Pichilingue research station. The percentage of epibiont coverage was calculated and analyzed. The average length of the thalli was 7.8 ± 4.6 cm. Eleven taxa of hydrozoans were recorded; the hydrozoan Obelia cf. dichotoma had the highest coverage percentage, and in summer, there was a higher taxa richness. It is recommended to monitor this macroalga and its epibionts for its wide distribution in the bay, although in UABCS, Pichilingue Pier has not seen epibionts that threaten biological diversity. [ABSTRACT FROM AUTHOR]

Energy security is a critical global challenge in the transition to sustainable development. Anaerobic digestion (AD) offers a promising renewable energy solution that mitigates environmental impacts. Algae, as biomass feedstock, have shown significant potential for bioenergy production; however, their complex chemical composition poses challenges to the efficiency of the AD process. To address these limitations, various pretreatment methods have been applied to enhance biogas production. In this study, we performed a comprehensive meta‐analysis to evaluate the effects of different pretreatments on methane (CH₄) yields from both microalgae and macroalgae. Our results demonstrate that biological, physical, and combined chemical–physical pretreatments significantly improve CH₄ production in microalgae, with increases of up to 141%, 125%, and 151%, respectively. For macroalgae, physical pretreatments were the most effective, leading to a 129% increase in CH₄ yield. We also estimate that utilizing just 10% of the global algal biomass production (3.6 Mt) could generate over 5.5 TWh y−1 of energy. This potential could be doubled with the application of appropriate pretreatment strategies. These findings highlight the role of algae in advancing renewable energy production and contribute to the growing body of knowledge on optimizing AD processes for cleaner energy generation. [ABSTRACT FROM AUTHOR]

Introduced seaweeds can alter the structure and productivity of marine food webs, especially when they lack top-down control by native herbivores. However, relatively little is known about the role of consumption of introduced seaweeds by native herbivores, and the potential role of seaweed nutrient content to mediate local herbivore consumption. In southeastern USA estuaries, the introduced red seaweed, Gracilaria vermiculophylla, has transformed unvegetated intertidal mudflats into a patchwork of non-native seaweed beds. We used a series of laboratory feeding assays to assess how invertebrate and fish species on the Georgia coast utilize G. vermiculophylla as a novel food resource. Because G. vermiculophylla readily absorbs nutrients, we also tested the role of nutrient enrichment on its consumption. We found that G. vermiculophylla was not significantly consumed by the mud snail Ilyanassa obsoleta nor the mud crab Eurypanopeus despressus, but it was rapidly eaten and even preferred over the native seaweed Ulva lactuca by adult pinfish Lagodon rhomboides. Nutrient enrichment of G. vermiculophylla did not affect consumption rates by the amphipod Ampithoe valida, but did double consumption rates by pinfish over unenriched seaweed. The differential responses of native consumers highlight the importance of evaluating multiple species when investigating introduced species' impacts on recipient communities. Given that consumer identity and nutrient content of the seaweed mediated the consumption of the non-native seaweed, site-specific patterns of consumer populations and environmental conditions could lead to patchy abundance and impacts of the non-native seaweed. [ABSTRACT FROM AUTHOR]

Risk is an inherent characteristic of aquaculture production. For a holistic understanding of risk, the risk assessment process must account for both subjective and objective dimensions of risk. This paper empirically studies the role of risk perception and the risk properties of inputs used in aquaculture to explain the low adoption rates of seaweed farming in Chile. We propose a risk production estimation framework with selectivity to explore the role of risk, given that many aquaculture concessions remain totally or partially unexploited. We found that farmers are more likely to produce seaweed when they perceive greater access to financing, but also that this activity is more exposed to theft than other activities. Moreover, results suggest that labor and energy are risk-increasing inputs, while we found that capital and the number of hectares available are risk-decreasing inputs. The latter is important as it suggests that larger seaweed producers and more investment would reduce production variability. [ABSTRACT FROM AUTHOR]

Marine brown algae produce the highly recalcitrant polysaccharide fucoidan, contributing to long-term oceanic carbon storage and climate regulation. Fucoidan is degraded by specialized heterotrophic bacteria, which promote ecosystem function and global carbon turnover using largely uncharacterized mechanisms. Here, we isolate and study two Planctomycetota strains from the microbiome associated with the alga Fucus spiralis, which grow efficiently on chemically diverse fucoidans. One of the strains appears to internalize the polymer, while the other strain degrades it extracellularly. Multi-omic approaches show that fucoidan breakdown is mediated by the expression of divergent polysaccharide utilization loci, and endo-fucanases of family GH168 are strongly upregulated during fucoidan digestion. Enzymatic assays and structural biology studies reveal how GH168 endo-fucanases degrade various fucoidan cores from brown algae, assisted by auxiliary hydrolytic enzymes. Overall, our results provide insights into fucoidan processing mechanisms in macroalgal-associated bacteria. Degradation of the recalcitrant polysaccharide fucoidan, produced by marine brown algae, is carried out by some bacteria through unclear mechanisms. Here, the authors provide insights into fucoidan processing mechanisms by studying two alga-associated bacterial strains, using microscopy, multi-omic, biochemical and structural techniques. [ABSTRACT FROM AUTHOR]

Influenza is a contagious viral infection of the respiratory tract, affecting nearly 10% of the world's population, each year. The aim of this study was to extract and identify antiviral compounds against the influenza-A virus (H1N1) from different species of Egyptian marine algae. Three samples of marine macroalgae species were extracted and the antiviral activity of the extracts were tested on Madin Darby Canine Kidney cells. The bioactive compounds present in the most active fractions were identified using gas chromatography-mass spectrometry (GC-MS), then the binding potentials of the identified compounds were examined towards neuraminidase (NA) of the influenza-A virus using molecular docking. The methanolic extract of Sargassum aquifolium showed promising in-vitro antiviral activity with a selectivity index (SI) value of 101. The GC-MS analysis showed twelve compounds and the molecular docking analysis found that tetradecanoic acid showed the strongest binding affinities towards the NA enzyme. [ABSTRACT FROM AUTHOR]

Portieria hornemannii, a marine red alga, has attracted considerable attention due to its possible therapeutic characteristics. NFκB, a crucial transcription factor involved in regulating immune and inflammatory responses, plays a central role in controlling the expression of various genes associated with inflammation, such as MMP 9. This study employed an aqueous extract of Portieria hornemannii (Ph) and subjected it to UV-Visible, FTIR spectroscopy, and GC-MS analysis to identify its phytochemical composition. The presence of Vanillin, tert-butyldimethylsilyl ether, Dodecane, 1-fluoro-, and Pentanoic acid, 5-hydroxy-2,4-di-t-butylphenyl esters in Ph indicates their potential anti-inflammatory properties, suggesting their potential application in inflammation treatment. In summary, Ph exhibited anti-inflammatory properties by modulating the expressions of NFκB-associated MMP 9 in zebrafish embryos, potentially reducing the risk of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Seaweeds are one of the major marine foods with high values. The diversity of seaweed species significantly impacts their quality and is closely linked to their purity and safety. For the first time, this study established a model to discriminate seaweed species using a multi-element fingerprinting approach for species identification. Twenty-nine elements derived from seaweeds were analyzed. Chemometrics showed that seaweed samples could be well separated by the established multi-element fingerprints, of which Ag, Mn, Sr, and K were the most important variables for discrimination. Furthermore, the present study proposed an innovative risk–benefit assessment strategy for seaweeds that considers both risks and benefits, developing a novel risk–benefit assessment model from both dietary and medicinal perspectives for the first time. Our innovative strategy was well-conceived to accurately and effectively differentiate seaweeds based on species and scientifically evaluate both benefits and risks associated with seaweeds. This strategy is poised to offer invaluable insights into the sustainable growth of the seaweed sector and to bolster public health initiatives, ensuring a robust and forward-looking approach to both industry and healthcare advancements. [ABSTRACT FROM AUTHOR]

Phase shifts from hard coral to macroalgae have led to the formulation of a top-down herbivory paradigm, whose assumption is that a reduction in herbivory is the primary driver of these changes. Caribbean parrotfish from Scarus and Sparisoma genera are usually known as main reef herbivorous. Yet, they are a diverse group of organisms that perform multiple functions, including the bioerosion of reef structures. Generalizing functions at the group level likely explains why the direct effects of parrotfish on macroalgae regulation are not always evident. In this study, we tested the hypothesis that parrotfish potential functions are strongly linked to the habitat's benthic characteristics. Furthermore, we expect that the parrotfish bioerosion potential will be highly sensitive to changes in benthic conditions, while herbivory will be more robust. We conducted in situ benthic and parrotfish surveys across the diverse reefscape of the remote Alacranes Reef, the most extensive system in the Gulf of Mexico. Both bioerosion and herbivory potential were highest in the most complex and structured sites, while only macroalgae removal was high in deep low-coral cover sites dominated by fleshy macroalgae. Interestingly, both functions were highly diminished in shallow and reticulated inner reefs dominated by turf algae and cyanobacteria, suggesting that even the herbivory function can be depleted under unfavorable benthic conditions. Our findings highlight the need to reconsider parrotfish management strategies to account for the specific roles of different species and consider reciprocal benthic-fish interactions. [ABSTRACT FROM AUTHOR]

Seaweed farming is a rising sector in European policy narratives and is increasingly integrated in coastal countries' bioeconomy strategies. Norway aims to lead this European 'Seaweed Revolution'. Envisioned as a 'billion‐euro industry', its development is in its infancy yet contains ambitions for upscaling and socio‐economic credentials that promote it as a sector for sustainable finance and investments. Through assemblage conceptualisation, the paper unfolds the relations that connect the fluid materialities of seaweed with ambitious business plans, coastal localities, calls for upscaling, complex markets and assesses the trajectories potentials for sector development. Instead of forecasting the future of seaweed farming in Norway, it displays how the sociospatial complexities of the Norwegian seaweed farming assemblages' components enable or disperse currently dominant and optimistic sectoral narratives, providing a critical window to highlight the underlying and partially contradictory processes that shape the development trajectories of a sector promoted as a beacon of sustainable transformation. [ABSTRACT FROM AUTHOR]

Bacteria and macroalgae share an inseparable relationship, jointly influencing coastal ecosystems. Within macroalgae habitats, Planctomycetota, a group of bacteria notoriously challenging to cultivate, often dominate. However, the mechanisms facilitating their persistence in this environment remain unclear. Here, we successfully isolated a novel Planctomycetota bacterium, Stieleria sp. HD01, from the surface of kelp. We demonstrated that HD01 possesses a robust ability to metabolize fucoidan, which constitutes half of the kelp‐derived organic carbon and exhibits resistance to attack by most microorganisms. Moreover, HD01 can utilize a broad spectrum of other organics, indicating its metabolic versatility and competitive prowess within algal environments. Additionally, HD01 can secrete antagonistic substances against other bacteria, form biofilms, and employ superoxide dismutase and catalase to resist oxidative stress, further consolidating its ecological fitness. Comparative metagenomics analysis suggested that Planctomycetota may have a mutually beneficial relationship with kelp. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the bioavailability of vitamin B12 from nori and to evaluate the required dosage for improving vitamin B12 nutritional status in vegetarians not using supplements. Methods: The study design is an open-label, parallel, dose-response randomized controlled trial. Thirty vegetarians were assigned to control (no nori), low-dose (5 g nori, aiming to provide 2.4 µg vitamin B12 per day), or high-dose (8 g nori, aiming to provide 4 µg vitamin B12 per day) groups. The primary outcome was changes in vitamin B12 status as measured by serum vitamin B12, holotranscobalamin (holoTC), homocysteine (Hcy), and methylmalonic acid (MMA), and a combined score of these four markers (4cB12 score) during the four-week intervention. Dietary vitamin B12 intakes were assessed at baseline and end of the trial with a 17-item food frequency questionnaire designed for vitamin B12 assessment. General linear model was used to compare least square means of changes in each biomarker of vitamin B12 status, among the three groups, while adjusting for respective baseline biomarker. Results: After adjusting for baseline status, nori consumption led to significant improvement in serum vitamin B12 (among-group P-value = 0.0029), holoTC (P = 0.0127), Hcy (P = 0.0225), and 4cB12 (P = 0.0094). Changes in MMA did not differ significantly across groups, but showed within-group pre-post improvement in the low-dose group (median [p25, p75] = -339 [-461, -198] nmol/L). Vitamin B12 status appeared to plateau at low dose (5 g of nori), which compared with control group, improved serum vitamin B12 (lease square mean [95% CI] = + 59 [25, 93] pmol/L, P = 0.0014); holoTC (+ 28.2 [10.1, 46.3] pmol/L, P = 0.0035); Hcy (-3.7 [-6.8, -0.6] µmol/L, p = 0.0226); and 4cB12 score (+ 0.67 [0.24, 1.09], p = 0.0036). High-dose resulted in similar improvements. There was no significant difference between low-dose and high-dose groups in all biomarkers of vitamin B12. Conclusions: Consuming 5 g of nori per day for 4 weeks significantly improved vitamin B12 status in vegetarians. A higher dose (8 g) may not confer additional benefits. Clinical trial registration: ClinicalTrials.gov Identifier: NCT05614960. Date of registration: November 14th 2022. [ABSTRACT FROM AUTHOR]

The Chinese goal to reach carbon peak by 2030 and achieve carbon neutrality by 2060 (the "30/60" dual carbon goal) will require a swift and dramatic reduction in greenhouse gas emissions. Among various ocean carbon dioxide removal (CDR) technologies, seaweed cultivation has gained more attention due to its potential for CO2 removal. However, the current legal framework in China lacks specific laws and regulations addressing seaweed cultivation for carbon removal. This paper highlights three key points: (1) the existing Chinese legal system needs to be updated to keep up with policy changes and govern the practice of seaweed cultivation for carbon removal; (2) transitioning seaweed cultivation from aquaculture to an ocean CDR approach can promote climate mitigation benefits; and (3) successful implementation requires not only technical and financial support but also the establishment of comprehensive policy and legal frameworks. [ABSTRACT FROM AUTHOR]

The increase in cancer incidence in recent years necessitates urgent exploration of novel and alternative sources of natural bioactives for targeted cancer therapy. Approximately 75% of the Earth's surface is covered by oceans, which are thought to harbor untapped physiologically active compounds with potential efficacy against cancer. Recently, a growing focus has been on isolating and investigating novel bioactive compounds derived from marine sources. Bioactive metabolites with diverse chemical structures, isolated from various marine species such as algae, mollusks, and actinomycetes, demonstrate potential efficacy against a wide range of cancers. To our knowledge, this is one of the articles that has reviewed recent papers on the application of marine-derived bioactives in targeted cancer therapy. This study aims to showcase some of the most current developments in targeted cancer therapy with various bioactives that have been identified from marine sources. [ABSTRACT FROM AUTHOR]

A celebrated result of Gromov ensures the existence of a contact structure on any connected, non-compact, odd-dimensional Lie group. In general, such structures are not invariant under left translation. The problem of finding which Lie groups admit a left-invariant contact structure resolves to the question of determining when a Lie algebra g is contact; that is, admits a one-form φ ∈ g ⁎ such that φ ∧ (d φ) k ≠ 0. In full generality, this remains an open question; however we settle it for the important category of the evocatively named seaweed algebras by showing that an index-one seaweed is contact precisely when it is quasi-reductive. Seaweeds were introduced by Dergachev and Kirillov who initiated the development of their index theory – since completed by Joseph, Panyushev, Yakimova, and Coll, among others. Recall that a contact Lie algebra has index one – but not characteristically so. Leveraging recent work of Panyushev, Baur, Moreau, Duflo, Khalgui, Torasso, Yakimova, and Ammari, who collectively classified quasi-reductive seaweeds, our equivalence yields a full classification of contact seaweeds. We remark that since type-A and type-C seaweeds are de facto quasi-reductive (by a result of Panyushev), in these types index one alone suffices to ensure the existence of a contact form. [ABSTRACT FROM AUTHOR]

The production of Litopenaeus vannamei has significantly intensified, and integrated multi-trophic aquaculture (IMTA) has emerged as an effective farming technique to sustain the shrimp industry. Integrated aquaculture reduces pollution while increasing aquaculture production. This production system could give both ecological and economic benefits. Its contribution to the reduced amount of nutrients from intensive shrimp farming effluents and to the improvement of water quality conditions and growth of white shrimp are significant. This study aimed to evaluate the impacts on water quality and growth performance of shrimp (L. vannamei) at the same time assess the viability of rearing shrimps integrated with either green mussel, Perna viridis (GM alone), GM+seaweed (Gracilariopsis bailiniae), GM+tilapia (Oreochromis mossambicus), or GM+seaweed+tilapia. Shrimps were cultured outdoors for 60 days in a recirculating system at an average water exchange rate of 6 L hr-1. Shrimps were stocked at 400 shrimp m-3 in shrimp tank while seaweed (2kg m-2), green mussels (50 individuals per meter line), and tilapia (350 grams m-3) were cultivated separately in plastic baskets inside the biofiltration tank. Shrimp effluents were recirculated from the shrimp tank to the biofiltration tank. After 60 days of culture, results showed that shrimps without integration had the lowest average body weight (ABW), survival, weight gain, specific growth rate (SGR), biomass gain, and high feed conversion ratio (FCR) compared to shrimps with integration. This experiment confirmed that shrimp can be cultured intensively with either green mussel (GM alone), GM+ seaweed, GM+tilapia, or GM+seaweed+tilapia without adversely affecting the water quality and its growth performance and could even result in better yield than the shrimp cultured without integration. This research demonstrated the benefits of integrated aquaculture and could be further verified using large-scale culture. [ABSTRACT FROM AUTHOR]

Genomic resources have yielded unprecedented insights into ecological and evolutionary processes, not to mention their importance in economic and conservation management of specific organisms. However, the field of macroalgal genomics is hampered by difficulties in the isolation of suitable DNA. Even when DNA that appears high quality by standard metrics has been isolated, such samples may not perform well during the sequencing process. We here have compared Oxford Nanopore long‐read sequencing results for three species of macroalgae to those of nonmacroalgal species and determined that when using macroalgal samples, sequencing activity declined rapidly, resulting in reduced sequencing yield. Chemical analysis of macroalgal DNA that would be considered suitable for sequencing revealed that DNA derived from dried macroalgae was enriched for polyphenol–DNA adducts (DNA with large polyphenols chemically attached to it), which may have led to sequencing inhibition. Of note, we observed the strongest evidence of sequencing inhibition and reduced sequence output when using samples dried using silica gel—suggesting that such storage approaches may not be appropriate for samples destined for Oxford Nanopore sequencing. Our findings have wide‐ranging implications for the generation of genomic resources from macroalgae and suggest a need to develop new storage methods that are more amenable to Oxford Nanopore sequencing or to use fresh flash‐frozen tissue wherever possible for genome sequencing. [ABSTRACT FROM AUTHOR]

Seaweed is a great source of biologically active metabolites which could prove interesting in cosmeceutical applications. In this study, seven Icelandic seaweed species (Ascophyllum nodosum, Alaria esculenta, Laminaria hyperborea, Laminaria digitata, Saccharina latissima, Palmaria palmata, and Schizymenia jonssonii) were screened for total polyphenol content, antioxidant properties, and inhibition of skin-degrading enzymes. Antioxidant assays included DPPH (2,2-diphenyl-1-picrylhydrazyl), reducing power, and ORAC (oxygen radical absorbance capacity). In most assays, A. nodosum extracts were the most active. A. nodosum extracts also showed the strongest inhibition of the skin-degrading enzymes elastase and collagenase at low concentrations, demonstrating its skin-protective qualities. To further investigate the activity, A. nodosum was subsequently extracted with solvents with increasing polarity into seven different extracts. Compared to other extracts, the extracts obtained by extraction with acetone and methanol showed the highest activity in all assays. Extracts obtained with room-temperature water and 85 °C water also demonstrated moderate to high activities. The outcomes of this study support the potential utilization of the brown seaweed A. nodosum as a source of natural ingredients in cosmeceuticals. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The 2 brown seaweeds, Fucus serratus and Fucus vesiculosus , have demonstrated antimethanogenic properties in vitro with reductions in CH 4 production ranging from 53 to 63%. This study aimed to investigate the effects of the 2 Fucus seaweeds on enteric CH 4 emissions, DMI, ECM, and nutrient digestibility when fed to dairy cows. The experiment was conducted using 4 multicannulated lactating Danish Holstein dairy cows, which over 3 experimental periods received either: (1) basal diet (CON; diet without any seaweed), (2) basal diet diluted with 4% (DM basis) Fucus serratus (SER), or (3) basal diet diluted with 4% (DM basis) Fucus vesiculosus (VES); resulting in one complete 3 × 3 Latin square and one incomplete 3 × 3 Latin square. Each period lasted 21 d and consisted of 14 d of adaptation, followed by 3 d of digesta sampling, and 4 d of gas exchange measurements using respiration chambers. Milk yield and feed intake were recorded daily. Blood samples were collected on d 15 and 17. All parameters were statistically analyzed using a mixed procedure of R. Opposite to what we had expected, neither of the 2 Fucus seaweeds reduced CH 4 emissions from the dairy cows as daily CH 4 production was significantly higher for both Fucus treatments compared with CON. Additionally, CH 4 yield (g CH 4 /kg DMI) and intensity (g of CH 4 /kg ECM) were significantly higher for SER compared with CON. Milk yield, DMI, and total-tract digestibility were unaffected by the treatments; however, SER resulted in lower milk protein yield (kg/d) and lower milk and blood plasma urea concentrations compared with CON. In conclusion, neither SER nor VES showed potential as methane-mitigating feed additives when fed to dairy cows at an inclusion level of 4% of DM. The inclusion of the 2 brown seaweeds had no effects on DMI, milk yield, or total-tract digestibility. [ABSTRACT FROM AUTHOR]

Animals combine colour change and behavioural choices to enhance concealment and adapt to changes in habitat in time and space. However, non‐native and invasive habitat‐forming plants and seaweeds can change the landscape, challenging animals to remain camouflaged, especially when the colour of the new habitat differs from the native backgrounds.The chameleon prawn (Hippolyte varians) exhibits remarkable colour variation and effective camouflage against different native seaweeds in shallow tidepools. Individuals optimize crypsis by choosing colour‐matching seaweeds and changing colour over time. In some locations, the prawn's native habitats are now replaced by non‐native seaweeds of different coloration and structure, making it important to understand whether substrate choice and colour change facilitates the occupation of these seaweeds and enables prawns to camouflage against new backgrounds.Using image analysis and visual modelling of a fish predator, we assessed the colour variation and camouflage of chameleon prawns occupying the non‐native seaweeds brown wireweed (Sargassum muticum) and pink harpoon weed (Asparagopsis armata) in southwest UK. We performed laboratory trials to examine whether prawns maintain their preference for colour‐matching native substrates when given a choice between them and non‐native seaweeds, and if they can change their coloration to improve camouflage against non‐native substrates.Prawns exhibit phenotypic diversity and camouflage that varied with the non‐native seaweed species, with low colour variation and effective camouflage on pink harpoon weed, but high colour diversity and reduced concealment against brown wireweed. Prawns choose non‐native seaweeds when the alternative native substrate provides mismatching coloration, but they did not exhibit any preference between colour‐matching native and non‐native seaweeds. Once in non‐native habitats, prawns change their appearance over a few days to match the background, sometimes faster than when changing on native seaweeds of contrasting coloration.Although human activities considerably modify the coloration of marine landscapes by increasing the establishment of non‐native seaweeds, the impacts of those changes appear less severe for colour‐changing species, such as chameleon prawns, and will depend on the similarity between the colour of the new substrates and the original native backgrounds, and how animals use behaviour and physiology to match new habitats. [ABSTRACT FROM AUTHOR]

The study commenced in March-September, 2023, in the canopy of the University of Kerbala, Kerbala, Iraq. The experiment's implementation relied on a completely randomized block design (RCBD) with three factors. The first was pomegranate (Punica granatum L.) cultivars (Wonderful and Slimi), the second was the marine algae extract at three concentrations (0, 1.5, and 3 ml L-1), and the third was the Humax acid at three concentrations (0, 0.25, and 0.50 g L-1). The most important results revealed the Wonderful cultivar significantly superior to the Slimi cultivar in all studied vegetative traits, recording the highest average of the following: increases in the seedling height, seedling stem diameter, the number of leaves per seedling, the total leaf area, relative moisture content in the leaves, and dry matter percentage. The marine algae treatment of 3 ml L-1 showed significant superiority to other extract concentrations in the vegetative growth trait. It included increases in the seedling height, seedling stem diameter, number of leaves per seedling, total leaf area, relative moisture content in the leaves, and dry matter percentage. Humax acid treatment of 0.50 g L-1 was notably better than the other Humax acid concentrations in all studied vegetative traits. [ABSTRACT FROM AUTHOR]

The current investigations on green onion (Allium cepa L.) commenced during the crop season of 2021-2022 at the University of Mosul, Mosul, Iraq. The presented research examined the effect of foliar application of humic acid and seaweed extract on the growth and production of green onions. The first factor involved spraying of humic acid (H) at different concentrations (0, 1, and 2 ml L-1). The second factor had the foliar application of seaweed extract (Super 50) (S) with different concentrations (0, 1, and 2 ml L-1). The study used the local onion cultivar Crystal in the research, planted in a randomized complete block design with three replications. Furthermore, spraying with seaweed extract, and humic acid not only exceeded the control treatment in tubular leaf count, bulb width, and bulb length, but also surpassed the vegetative growth and growth rate in onions. The best measurements came from the foliar treatment, where the interaction of humic acid with seaweed with the same concentration (2 ml L-1) resulted in no significant differences for growth traits and bulb yield. However, the bulb yield was 693.3 t ha-1 in the experimental treatments, while 553.3 t ha-1 for the control group. [ABSTRACT FROM AUTHOR]

Brown algae are one of the most abundant biomasses on Earth. To recycle them as blue carbon sources, an effective decomposition system is necessary. This study focused on microorganisms present in seawater that decompose brown algae which contain laminarin and alginate. Where Undaria and Sargassum spp. were present, genera Psychromonas, Psychrobacter , and Pseudoalteromonas were predominant in seawater, while genera Arcobacter and Fusobacterium increased in abundance during the process of decomposition. The inoculation of Undaria samples into laminarin-minimal media led to a predominance of Pseudoalteromonas species. A Pseudoalteromonas isolate, identified as Pseudoalteromonas distincta , possesses genes encoding a putative laminarinase, polysaccharide lyase family 6 (PL6) alginate lyases, and a PL7 alginate lyase. The culture media of P. distincta contained no monosaccharides, suggesting the rapid conversion of polysaccharides to metabolites. These findings indicated that Pseudoalteromonas species play a major role in the decomposition of brown algae and affect the microbiota associated with them. [ABSTRACT FROM AUTHOR]

Halimeda macroloba (H. macroloba) a seaweed commonly known as green macroalgae is a potential source of bioactive compounds utilised in nutraceuticals and pharmaceuticals. However, there are no reliable scientific studies that describe harmful consequences, which attest to its safety. Thus, the current investigation focuses on a 14-day acute toxicity assessment of H. macroloba hydroalcoholic extract (HME). HME was prepared using 70 % alcohol as solvent by the maceration method for 72 h and Soxhlet method. Phytochemical analysis was done using standard procedures, according to OECD 423 guidelines. Female Wistar albino rats fasted overnight and received a single oral dosage of 50, 300, and 2,000 mg/kg BW (body weight). Further rats were starved for 4 h and watched individually for every 30 minutes, then twice a day for 14 days. To determine the toxicity overall behaviour, BW, haematological, biochemical, histopathology, and gross morphology were examined. Pharmacologically active phytoconstituents were identified by phytochemical analysis. No significant abnormalities/fatalities from single-dose of HME at escalating doses. No BW or behavioural changes. The majority of the haematological and biochemical parameters were normal. Did not show any apparent changes. simultaneously, a few indicated slight variations that may or may not be caused by HME extract no lesions or anomalies in Gross morphology. Histopathological investigations revealed that HME had no adverse effects on organs. HME administration at doses up to 2,000 mg/kg BW didn't result in acute toxicity/impairment to the pancreas, liver or kidney. Nevertheless, the study's limited test dose of 2,000 mg/kg, BW, didn't result in any fatalities/ adverse effects. [ABSTRACT FROM AUTHOR]

The efficient cathode material helps to improve the removal of antibiotics in the electro‐Fenton (EF) system. The simultaneous doping of transition metals and heterogeneous non‐metallic elements in biochar electrodes can enhance the performance of EF systems, but the catalytic mechanism for EF needs to be further explored. In this study, novel Fe/S‐doped biochar cathodes derived from marine algae (MA) were prepared to investigate the removal rate of ceftriaxone sodium (CS) and the underlying mechanisms. The results indicated that the Fe/S modified MA (Fe/S/MA) biochar cathode showed the highest CS removal rate (71.23%) in the EF system when treating 20 mg/L CS solution containing 8 mg/L Fe2+ at pH 4. Scanning electron microscopy and X‐ray photoelectron spectroscopy analyses revealed that this cathode provided more iron and sulfur active sites for catalyzing the oxygen reduction reaction to produce H2O2, enhanced surface porosity, and improved CS removal rate. Electrochemical tests demonstrated this cathode possessed high electrocatalytic capacity, rapid charge transfer capability, and low electrode resistance. This suggested that it can provide more oxygen reduction reaction sites to promote ∙OH generation and enhance Fe2+ regeneration for improving CS removal. This study demonstrates the Fe/S/MA biochar cathode in the EF system shows great potential for the removal of antibiotics. [ABSTRACT FROM AUTHOR]

Metabolic Syndrome (MetS) is a complex, multifactorial condition characterized by risk factors such as abdominal obesity, insulin resistance, dyslipidemia and hypertension, which significantly contribute to the development of cardiovascular disease (CVD), the leading cause of death worldwide. Early identification and effective monitoring of MetS is crucial for preventing serious cardiovascular complications. This article provides a comprehensive overview of various biomarkers associated with MetS, including lipid profile markers (triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and apolipoprotein B/apolipoprotein A1 (ApoB/ApoA1) ratio), inflammatory markers (interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), plasminogen activator inhibitor type 1 (PAI-1), C-reactive protein (CRP), leptin/adiponectin ratio, omentin and fetuin-A/adiponectin ratio), oxidative stress markers (lipid peroxides, protein and nucleic acid oxidation, gamma-glutamyl transferase (GGT), uric acid) and microRNAs (miRNAs) such as miR-15a-5p, miR5-17-5p and miR-24-3p. Additionally, this review highlights the importance of biomarkers in MetS and the need for advancements in their identification and use for improving prevention and treatment. Seaweed therapy is also discussed as a significant intervention for MetS due to its rich content of fiber, antioxidants, minerals and bioactive compounds, which help improve cardiovascular health, reduce inflammation, increase insulin sensitivity and promote weight loss, making it a promising nutritional strategy for managing metabolic and cardiovascular health. [ABSTRACT FROM AUTHOR]

Background/Objectives: Fucoidan, a sulfated polysaccharide derived from marine algae, is known for its antioxidant and immunomodulatory properties. Galectin-3 (Gal-3), a protein associated with cardiovascular fibrosis, has been identified as a potential therapeutic target in cardiac remodeling. This study aimed to evaluate whether fucoidan could inhibit Gal-3 activity and mitigate cardiac remodeling in a mouse model of pressure overload-induced cardiac hypertrophy. Methods: To test this hypothesis, we used transverse aortic constriction (TAC) surgery to induce pressure overload in normotensive mice, replicating the pathological features of cardiac hypertrophy. Mice were treated with fucoidan at a dose of 1.5 or 7.5 mg/kg/day. In vivo assessments of cardiac function, fibrosis, inflammation, and Gal-3 expression were performed. Results: Pressure overload led to significant upregulation of serum Gal-3 levels, increased cardiac collagen deposition, and elevated markers of fibrosis and inflammation. In mice treated with fucoidan, these effects were significantly attenuated. Fucoidan treatment prevented the upregulation of Gal-3, reduced collagen deposition, and decreased inflammatory cell infiltration, suggesting an inhibition of both fibrosis and inflammation. Conclusions: Fucoidan effectively mitigated the adverse effects of pressure overload in this mouse model, including reduced Gal-3 expression, fibrosis, and inflammation. These findings suggest that fucoidan holds promise as a therapeutic agent for preventing or delaying cardiac remodeling and associated complications, such as fibrosis and inflammation, in pressure overload-induced cardiac hypertrophy. Further research is needed to explore the underlying mechanisms and clinical applicability of fucoidan in cardiac disease. [ABSTRACT FROM AUTHOR]

This paper is dedicated to soft grippers, robot tools with a wide application area in various activities where an accurate and delicate grabbing movement is required such as routine manipulation tasks with fragile objects, operation in unknown or dangerous environments, and manipulation with unknown shape objects, as well as exploring the depths of the sea or harvesting vegetables in agriculture. The main goal of this paper is to review and systematize the main ideas about and achievements of soft grippers published from 2015 to 2024. The paper provides a statistical analysis of the performed research and systematized advancements of soft grippers according to their operating principle, forces and effects that enable their operation, and the properties of potential manipulation objects. Grippers inspired by nature are also discussed, as most successful solutions are based on ideas derived from nature. This study discusses the latest achievements of soft grippers and their various applications and presents a unique distribution of soft grippers according to the physical principle of the forces they act on, according to the size of the object to be grasped, and according to technological realizations. The results of this analysis can be useful for practical gripper users aiming to improve their workplace and find optimal design solutions, for gripper manufacturers or developers, or for scientists of material sciences looking for applications for their products. [ABSTRACT FROM AUTHOR]

Sargassum algae, being able to proliferate without the need to be attached to a substrate, travel through the ocean generating massive stagnations on the Caribbean coasts of the continent, becoming an environmental problem. Because its composition mainly includes polysaccharides, such as cellulose and hemicellulose, these algae were used to produce nanocellulose and create hydrogels to apply to germination. This article aims to develop of nanocellulose hydrogels from Sargassum and study the effect of it adding nanocellulose hydrogels from Sargassum algae loaded with Ca-PO4- and NO3 as nutrients in the germination process. The Sargassum algae used underwent two hydrolysis processes, one basic and one acid, with which it was possible to increase the cellulose content from 25.7 ± 0.42% to 34.05 ± 0.39 after the first hydrolysis and after 90.15 ± 0.44% after the second. Size reduction to nanocellulose was performed employing an ultrasonic homogenizer sonicator. The obtained nanocellulose was characterized using infrared spectroscopy, X-ray diffraction, and transmission electron microscopy, showing that by the alkaline method, the sizes were between 135-190 nm while by the acid method, the fiber sizes were between 108-163 nm with a difference of 1.04 in the crystallinity index between the two hydrolyses. With the nanocellulose, hydrogels were formed using 5%, 10%, and 15% borax as crosslinking agents. Drying curves and scanning electron microscopy were performed on the hydrogels. Nutrients Ca-PO4-NO3 were added to the hydrogel and their release in water was studied through Ultraviolet-Visible spectrophotometry, with which it was decided to use the hydrogel containing 10% borax in the germination study. The effect of the hydrogel loaded with nutrients on the germination of bean and linseed seeds employing a complete factorial design 23. Obtaining results that the nutrient with the greatest influence on germination was nitrogen while the nutrient with the least favorable results was the match. [ABSTRACT FROM AUTHOR]

Biomass harvesting represents one of the main bottlenecks in microalgae large-scale production. Solid–liquid separation of the biomass accounts for 30% of the total production costs, which can be reduced by the use of flocculants as a pre-concentration step in the downstream process. The natural polymer chitosan and the two chemical flocculants FeCl3 and AlCl3 were tested on freshwater Chlorella sorokiniana and two marine algae, Dunaliella tertiolecta and Tetraselmis striata. A preliminary screening at the laboratory scale was performed to detect the most suitable doses of flocculants. On the basis of these results, selected doses were tested on the pilot scale, using the flocculants for a pre-concentration step and the centrifugation as a second step to confirm the effectiveness of flocculants in a realistic operational environment. The biomass recoveries (Rpilot, %) of 100 L cultures were as follows: (1) for T. striata, Rpilot = 94.6% for 0.08 g/L AlCl3, 88.4% for 0.1 g/L FeCl3, and 68.3% for 0.04 g/L chitosan; (2) for D. tertiolecta, Rpilot = 81.7% for 0.1 g/L AlCl3, 87.9% for 0.2 g/L FeCl3, and 81.6% for 0.1 g/L chitosan; and (3) for C. sorokiniana, Rpilot = 89.6% for 0.1 g/L AlCl3, 98.6% for 0.2 g/L FeCl3, and 68.3% for 0.1 g/L chitosan. Flocculation reduced the harvesting costs by 85.9 ± 4.5% using chemical flocculants. Excesses of aluminum and iron in the biomass could be solved by decreasing the pH in the biomass combined with washing. This is the first study, to the best of our knowledge, that investigates the pilot-scale flocculation of three native Canarian microalgal strains. A pilot-scale pre-concentration step before centrifugation can improve the yield and reduce costs in the microalgae harvesting process. [ABSTRACT FROM AUTHOR]

Scaffolds resembling the extracellular matrix (ECM) provide structural support for cells in the engineering of tissue constructs. Various material sources and fabrication techniques have been employed in scaffold production. Cellulose-based matrices are of interest due to their abundant supply, hydrophilicity, mechanical strength, and biological inertness. Terrestrial and marine plants offer diverse morphologies that can replicate the ECM of various tissues and be isolated through decellularization protocols. In this study, three marine macroalgae species—namely Durvillaea poha, Ulva lactuca, and Ecklonia radiata—were selected for their morphological variation. Low-intensity, chemical treatments were developed for each species to maintain native cellulose structures within the matrices while facilitating the clearance of DNA and pigment. Scaffolds generated from each seaweed species were non-toxic for human dermal fibroblasts but only the fibrous inner layer of those derived from E. radiata supported cell attachment and maturation over the seven days of culture. These findings demonstrate the potential of E. radiata-derived cellulose scaffolds for skin tissue engineering and highlight the influence of macroalgae ECM structures on decellularization efficiency, cellulose matrix properties, and scaffold utility. [ABSTRACT FROM AUTHOR]

Coastal mussel populations have declined worldwide, largely due to overharvesting, water pollution, climate change, invasive species and other anthropogenic stressors. Mussel restoration projects have emerged to combat these declines, with restoration methods primarily prioritizing mussel transplantations from healthy populations into degraded areas. While this technique can be effective, it is also costly and often infeasible to upscale. One alternative restoration technique is assisted juvenile recruitment through plantigrade or spat provision, which has facilitated the creation of mussel reefs on small scales. This study assessed the effectiveness of upscaled assisted recruitment of juvenile mussels, specifically using plantigrades attached to macroalgae experimentally placed into restored mussel reefs and adjacent bare cobble habitat. Ultimately, low natural settlement of plantigrades to macroalgae (eight plantigrades per gram macroalgae) and high post‐settlement losses of plantigrades (> 99%) resulted in assisted recruitment being unsuccessful as very few juvenile mussels small enough to have originated from the plantigrade provision (0.6 juveniles/m2) were found in either habitat. These results demonstrate two key barriers limiting the success of assisted recruitment as a restoration technique: highly variable natural settlement processes to macroalgae and low successful progression from post‐settlement plantigrades to established juveniles due to mortality or emigration. Addressing these limitations will require assessing more reliable sources of plantigrades, such as hatcheries, and identifying the mechanisms currently impeding the transition of plantigrades to juvenile recruits. [ABSTRACT FROM AUTHOR]

Macroalgal beds are increasingly recognised as nursery habitats for coral reef fish; however, the extent to which they are used as a source of food and/or a refuge from predation remains largely unexplored. Here, we investigate the distribution, feeding behaviour, diet, and predation risk for juvenile rabbitfish in macroalgal habitats on Orpheus Island, Great Barrier Reef. Visual surveys revealed that juvenile and adult Siganus doliatus had different among-habitat distributions with juveniles being largely restricted to the reef flat and positively associated with macroalgal cover, while adults were abundant on the reef crest. Focal feeding observations show that within macroalgal habitats, juvenile S. doliatus targeted epiphytes on Sargassum (80% of bites), with relatively few bites taken on turfs or the Sargassum itself (27% and 8%, respectively). These observations were supported by stomach content analyses with filamentous algae being the dominant item in the stomach content of both small (< 4 cm total length, TL; 58%) and large juvenile S. doliatus (> 4 cm TL; 47%). The stomach content of juvenile S. doliatus, S. canaliculatus, and S. spinus collected from macroalgal habitats was similar, consisting primarily of filamentous algae and detritus. We found no relationship between the abundance of potential predators and juvenile rabbitfishes across the study sites. Collectively, our results suggest that juvenile rabbitfishes are using macroalgal habitats on this, and potentially other, inshore reefs as a food source and add to a growing body of literature highlighting the importance of these habitats for the early life stages of reef fish. [ABSTRACT FROM AUTHOR]

Climate-driven species range expansions are underway with more tropically affiliated species, including Scleractinian corals, becoming increasingly abundant at higher latitudes. However, uncertainty remains on how these range shifts will affect reef-scale ecosystem processes, which will ultimately depend on the traits of the taxa that dominate these assemblages. Here, we quantified spatiotemporal patterns in the taxonomic and trait structure of coral assemblages along the subtropical-temperate coast of Western Australia (27°–34°S). Coral abundance was generally low and coral cover < 5% across our study sites. Coral assemblages shared similarities in morphological trait structures across the latitudinal gradient, mostly characterised by taxa with simple morphologies; yet subtle differences were also observed across latitudes, with high-latitude corals characterised by slower growth rates and reduced maximum colony sizes. We found a 3.4-fold increase (from 1 to 3.4 individuals m−2) in coral abundance at one heavily disturbed location, where canopy-forming seaweeds were replaced by turfing algae, a pattern that was partly driven by an increase in the relative contribution of warm affinity taxa, such as Acropora spp. We predicted these changes would be reflected in different components of functional diversity; yet, despite a localised signal of tropicalisation, we only observed subtle changes in the functional identity, richness, evenness, and divergence. The spatially invariant trait structure of coral assemblages suggests that the nature of ecosystem functions will likely remain unchanged during early stages of tropicalisation, and hence their contribution to temperate reef-scale ecological processes will depend on dominance over other benthic foundational species. [ABSTRACT FROM AUTHOR]

Joint species distribution models (JSDMs) have gained considerable traction among ecologists over the past decade, due to their capacity to answer a wide range of questions at both the species‐ and the community‐level. The family of generalised linear latent variable models in particular has proven popular for building JSDMs, being able to handle many response types including presence‐absence data, biomass, overdispersed and/or zero‐inflated counts.We extend latent variable models to handle percent cover response variables, with vegetation, sessile invertebrate and macroalgal cover data representing the prime examples of such data arising in community ecology.Sparsity is a commonly encountered challenge with percent cover data. Responses are typically recorded as percentages covered per plot, though some species may be completely absent or present, that is, have 0% or 100% cover, respectively, rendering the use of beta distribution inadequate.We propose two JSDMs suitable for percent cover data, namely a hurdle beta model and an ordered beta model. We compare the two proposed approaches to a beta distribution for shifted responses, transformed presence‐absence data and an ordinal model for percent cover classes. Results demonstrate the hurdle beta JSDM was generally the most accurate at retrieving the latent variables and predicting ecological percent cover data. [ABSTRACT FROM AUTHOR]

Settlement induction potential of two red algae, Sahlingia subintegra and Rhodosorus marinus, and one green macroalgae, Ulvella leptochaete was examined to identify potential alternative algal species to improve reliability and reproducibility of Haliotis tuberculata sp. settlement. CCA was used as a positive control. Settlement rates, post-larval survival and growth of Haliotis tuberculata sp. were evaluated for different algal species tested. Results showed that Sahlingia subintegra induced significantly higher settlement rates (58.17 ± 12.71%) compared to CCA, Ulvella leptochaete and Rhodosorus marinus. In all treatments, post-larvae were weekly fed a mix of diatoms (Amphora sp., and Navicula incerta). At four weeks post settlement, post-larval survival rates were significantly higher on CCA and Sahlingia subintegra substrates compared to the other two algal species tested. However, at four and five weeks post settlement there were no significant differences in post-larval shell length and growth rates between CCA and Sahlingia subintegra substrates. These findings suggest that Sahlingia subintegra could be a promising alternative red macroalgae providing settlement cue for abalone hatchery stages, particularly for Haliotis tuberculata sp. and could contribute to improve abalone breeding techniques through the selection of alternative settlement substrates that could be easily managed in abalone farms environments. [ABSTRACT FROM AUTHOR]

In Australia, cultured greenlip abalone (Haliotis laevigata) are fed formulated diets that lack macroalgae. This has resulted in a pale lip colour in contrast to the vivid green lip colour of wild abalone. We evaluated the effects of supplementing 15% dried macroalgae meal, using either commercially available macroalgae meal (MSM) or harvested Gracilaria cliftonii, on colour change in greenlip abalone. Abalone were fed the respective diets in a three month laboratory trial and an additional four month on-farm trial. The inclusion of MSM into formulated abalone diet did not change lip, foot, or shell colour, whereas the G. cliftonii meal treatment changed lip and shell colour. The laboratory study was extended for another three months. Greenlip abalone either: (1) continued to be fed their experimental diet; or (2) the abalone were fed a diet with no dried algal meal. The colour changes observed in the first study were retained for one month, after which the colour declined. The addition of 15% G. cliftonii meal to formulated diets can be used to manipulate greenlip abalone lip and shell colour. A minimum of three months is recommended and abalone should be harvested within one month to maintain the desirable colour changes. [ABSTRACT FROM AUTHOR]

Caulerpa is a widely distributed genus of chlorophytes (green macroalgae) which are important for their dietary, social and coastal ecosystem value. Ocean acidification (OA) threatens the future of marine ecosystems, favouring macroalgal species that could benefit from increased seawater carbon dioxide (CO2) concentrations. Most macroalgae species possess CO2 concentrating mechanisms (CCMs) that allow active uptake of bicarbonate (HCO3−). Those species without CCMs are restricted to using CO2, which is currently the least abundant species of dissolved inorganic carbon (DIC) in seawater. Thus, macroalgae without CCMs are predicted to be likely benefit from OA. Caulerpa is one of the rare few genera that have species both with and without CCMs. The two most common Caulerpa species in New Zealand are C. geminata (possesses a CCM) and C. brownii (non-CCM). We investigated the responses of growth, photo-physiology and DIC utilisation of C. geminata and C. brownii to four mean seawater pH treatments (8.03, 7.93, 7.83 and 7.63) that correspond to changes in pH driven by increases in pCO2 simulating future OA. There was a tendency for the mean growth rates for C. brownii (non-CCM) to increase under lower pH, and the growth rates of C. geminata (CCM) to decline with lower pH, although this was not statistically significant. However, this is likely because variability in growth rates also increased as seawater pH declined. There were few other differences in physiology of both species with pH, although there was tendency for greater preference for CO2 over HCO3− uptake in the CCM species with declining seawater pH. This study demonstrates that DIC-use alone does not predict macroalgal responses to OA. [ABSTRACT FROM AUTHOR]