Land-use changes were assessed using isotopic and elemental composition of organic matter (OM) and organic pollutants in estuarine sediments from two Brazilian basins: the Caeté River (CR, Amazon Rainforest) and the Paraíba do Sul River (PSR, Atlantic Rainforest). Between 1985 and 2024, anthropogenic land use in CR increased in 39%, while PSR decreased by 2.6%. CR sediments exhibited lower δ13Corg (-27.3 ± 0.9‰) and δ15Ntotal (2.1 ± 2.2‰) than PSR (-23.6 ± 2.9‰ and 5.6 ± 1.0‰, respectively). Seasonal variability occurred only in CR, with more 13C-depleted and 15N-enriched values in the rainy season, suggesting surface runoff of C3-derived OM from rainforest or mangroves and upstream anthropogenic inputs. The Bayesian mixing model (MixSIAR) indicated clear contrasts in OM sources between basins. In the CR basin, sedimentary OM was predominantly derived from mangroves (median = 0.76), with a secondary contribution from sewage (0.18). In contrast, in the PSR basin, sewage was the dominant OM source (0.65), followed by mangrove contributions (0.28). Organic pollutants correlated with OC, showing that contaminant distribution is partly governed by OM dynamics. PAH diagnostic ratios revealed the sewage, biomass/coal burning as the main source in PSR, with additional fossil-fuel inputs, while CR reflected mixed combustion sources linked to agricultural fires and boat traffic. Organochlorine patterns in CR suggest historical pesticide use and diffuse atmospheric input, while PSR shows lindane and local/industrial influences. These results highlight contrasting OM dynamics under different land-use intensities and the dual role of estuaries in storing carbon and pollutants.

In the Amazon Coastal Zone (ACZ), the massive sediment input from the Amazon River dominates the coastal environment. However, the eastward transport of these sediments is limited by the predominant westward pattern of winds, waves, and currents. In contrast, extensive tidal flats and mangroves have developed along this sector, where local rivers do not provide significant sediment inputs and therefore are not the leading sediment suppliers. In this context, this study aims to understand the provenance of inorganic and organic sediments deposited in an estuary without effective fluvial input, thereby clarifying the role of Amazon River sediments in the southeastern ACZ (SACZ). For this purpose, estuarine and inner shelf bottom samples were collected and subjected to sedimentary, geochemical (XRF), radiogenic isotope, and biogeochemical analyses (C and N contents and their stable isotopes). In the estuary, the role of the local terrigenous source is highlighted, with organic sediments showing typical terrigenous organic matter signals, and inorganic sediments emphasizing the contribution of cratonic sources to sediment supply. On the inner shelf, two distinct patterns are observed: one evidences the influence of Amazon River input on organic and inorganic sediments located in the western portion of the study area; the other highlights the role of cratonic sources for inorganic sediments and the contribution of terrigenous sources, such as mangroves, to the organic matter dispersed on the shelf. This study underscores the complexity of sediment provenance in the SACZ and demonstrates the need for more detailed source-to-sink studies along the Amazon coast.

Tidal channels are fundamental pathways for the exchange of water, nutrients, and sediments in estuarinemangrove systems. Along the Amazon coast (western Equatorial Atlantic Ocean), more than 20 estuarine systems encompass approximately 8000 km2 of mangroves interconnected by tidal channels. This study focuses on one such channel, the Muria Channel, which is distinctive due to its structural origin, in contrast to the more common morphodynamic origin of most tidal channels. We conducted seasonal bathymetric, sedimentologic, and hydrodynamic surveys, capturing longitudinal and cross-sectional variations, along with detailed measurements at both ends of the channel (the Mocajuba and Curu & ccedil;a estuaries). Results indicate that the channel is deep, with an average depth (10 m) twice the mean spring tidal range (5 m). Bottom morphology and sediment mapping revealed basement outcrops and minimal temporal variation. This stability contrasts with the dynamic equilibrium of shallow, high-connectivity tidal channels, where frequent sediment resuspension and deposition drive morphological change. The channel's structural framework maintains its characteristic deep, narrow morphology, which sustains continuous hydrodynamic circulation throughout the tidal cycle. This configuration results in substantially reduced bed shear stresses and minimized sediment transport convergence - both key factors that typically promote rapid infilling and instability in shallower systems. Acting as a conduit between the Mocajuba and Curu & ccedil;a estuaries, the channel facilitates seasonal import of Amazon-derived particulate matter, imparting a distinct rainy-season signature to the system's sediment composition and dynamics.

The hydrodynamics of the inner shelf east of the Amazon River mouth in the Southeastern Amazon Coastal Zone (SACZ) are examined based on 1.5 years of observations of wind and currents. A meteorological station was established onshore to record the wind data, while an acoustic Doppler current profiler was moored offshore at a depth of 22 m. This is the first observational dataset of such length and quality east of the Amazon River mouth off SACZ. The results reveal two primary modes of hydrodynamic variation associated with the zonal migration of the Intertropical Convergence Zone (ITCZ), which significantly influences the regional wind regime. The first mode, termed "wet", occurs when the ITCZ shifts southward, leading to brief periods (hours to days) of wind relaxation. In contrast, the second mode, referred to as "dry", is characterized by a northward displacement of the ITCZ, resulting in more intense and consistent wind conditions. Throughout the year, the hydrodynamics are predominantly controlled by semidiurnal meso (neap) and macro (spring) tidal regimes, accounting for more than 98 % of the variance in cross-shelf currents and more than 90 % of longitudinal currents. This dominance is especially pronounced during the dry mode. In the wet mode, the current regime exhibits greater vertical variability, with low-frequency currents near the surface potentially dominating (>80 %). These low-frequency currents are associated with periods of wind relaxation and the eastward advance of the Amazon River plume. During the dry mode, low-frequency currents are influenced primarily by wind action, with a secondary contribution from the synodic modulation of tidal amplitude.

Mangroves are globally distributed ecosystems that provide numerous ecosystem services. They act as natural barriers along coastlines, mitigating the impact of waves and tidal forces. In doing so, they play a crucial role in controlling erosion and providing various resources for local human populations. The eastern sector of the Amazon coastal zone boasts the world's longest continuous mangrove belt, covering approximately 8000 km2. The regional dynamics are intense due to persistent Northeastern trade winds, associated wave climate, and a macrotidal regime, all of which shape the fringing mangroves responsible for coastal protection, sediment stabilization, and biodiversity. This study, therefore, assesses the extent of tidal current attenuation by fringe mangroves and its consequent influence on sediment transport and deposition. Current meters, pressure sensors/ data loggers, and turbidity meters were deployed at three points along a transversal transect. The composition and structure of the mangrove forest along the transect were also investigated, using saltmarsh beds (Spartina alterniflora) as the proximal Station P1 and the mangrove forests (Laguncularia racemosa, Avicennia germinans, and Rhizophora mangle) as the intermediate and distal Stations P2 and P3, respectively. Our findings indicate a direct correlation between vegetation density and flow attenuation. An integrated analysis reveals an ebb-dominant flow pattern, where transport from the mangrove forest to the tidal channel predominates, contributing to observed mangrove progradation. Understanding sediment dynamics and balance in mangrove forests is key to managing coastal ecosystems in a scenario of sea-level rise. Our findings reinforce how critical sediment supply is for fringing mangrove areas.

The coastal region serves as a crucial link between the ocean and the mainland, with its morphology significantly shaped by seasonal meteorological and oceanographic conditions. This study was conducted in Salinopolis, located in the state of Para in northern Brazil, along the eastern sector of the Amazon coast. This area is characterized by a coastal system influenced by semi-diurnal macro tides and waves, alongside notable seasonality in rainfall patterns. Data collection occurred during 2022 and 2023, encompassing both dry and rainy seasons and including neap and spring tides. Observations were made at two sites: a mangrove forest (P1) and a reconstructed retaining wall (P2) designed to mitigate erosion. The data collected included current speed and direction, turbidity, and salinity. Results revealed a 70-80 % reduction in current velocity at the mangrove site (P1) compared to the retaining wall site (P2), underscoring the mangrove forest's effectiveness in dampening wave and tidal energy. Salinity varied significantly between the dry (similar to 30 PSU) and rainy (similar to 8 PSU) seasons, showing a 70 % reduction. Additionally, suspended sediment concentration was higher during the rainy season (similar to 114 mg/ L), representing an 80 % increase compared to the dry season (similar to 29 mg/L), attributed to higher sediment input from local rivers. This study represents the first evaluation of mangrove forests as nature-based solutions for coastal protection in the Amazon region. It highlights the potential of such ecosystems not only for coastal preservation but also for the conservation of the region's threatened biodiversity, which is increasingly at risk due to coastal urban development.

Mangroves are essential tropical ecosystems nurturing a wide range of marine biodiversity and counteracting global warming by sequestering atmospheric carbon dioxide. Hence, the export mechanisms and fluxes of particulate and dissolved organic carbon and trace elements from mangroves directly influence coastal productivity, the global carbon cycle and thus global climate, which are, however, not well constrained. Here we find consistent radiogenic neodymium and hafnium isotopic compositions of porewater, sedimentary iron-manganese oxyhydroxides and coastal seawater, suggesting that the Amazonian mangrove belt supplies trace elements through porewater discharge, dissolution of iron-manganese oxyhydroxides and their interactions with seawater. Together, these processes supply 8.4 × 106 g yr-1 dissolved neodymium, equivalent to 64

Mangrove-fringed estuaries are intertidal ecosystems discharging significant amounts of dissolved organic matter (DOM) into coastal oceans. DOM in these ecosystems is derived from autochthonous production, fluvial input, and mangrove porewater outwelling; however, differentiating between these sources remains challenging. Our incomplete understanding of the biogeochemical factors controlling DOM dynamics and its relationship with nutrient and trace metal cycling still hinders the formulation of elemental budgets in coastal environments. Here, we relate the DOM composition in a mangrove-fringed estuary in North Brazil (Amazonia) to the redox conditions at the formation sites. We combined molecular DOM analyses via ultrahigh-resolution mass spectrometry (FT-ICR-MS) with parallel factor analysis of excitation-emission fluorescence matrices (EEM-PARAFAC), nutrient and redox-sensitive trace metal analyses. During low tide, the influx of oxygen-depleted porewater carried terrigenous DOM, inorganic nutrients, and trace metals into the mangrove-fringed creeks. Precipitation of metal(hydr)oxides and microbial turnover controlled nutrient and trace metal dynamics in the estuary. The highest inorganic nitrogen concentrations within the upper mangrove-fringed estuary indicated outwelling from mangrove sediments as an essential source. Phosphate concentrations were highest within the lower mangrove-fringed estuary, where available phosphate likely exceeded precipitation with iron(hydr)oxides. We tracked the DOM transport to the coastal ocean using a novel molecular index derived from sulfidic porewater (ISuP). Outwelling of recalcitrant DOM from mangrove habitats is relevant in the context of blue carbon storage. Therefore, applying our molecular proxy (ISuP), together with trace-metal and optical DOM analyses, is a powerful approach for differentiating contributions of diverse DOM sources in highly complex coastal ecosystems.

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This study investigates the geochemical characteristics and evolutionary implications of sediments at the confluence of the Xingu and Amazon Rivers. The main objective is to understand sediment mixing, mobility, and weathering processes through geochemical proxies. Samples were collected from various sections of the lower Xingu River, focusing on its interaction with the Amazon River. Analytical techniques such as X-ray diffraction (XRD), X-ray fluorescence (XRF), and inductively coupled plasma mass spectrometry (ICP-MS) were employed to analyze major and trace elements. The results reveal significant spatial variations in mineralogical and textural patterns, with sediments forming distinct groupings based on their location. The data suggest that the lower Xingu River is strongly influenced by sediment inputs from the Amazon River, particularly affecting sediment composition and chemical weathering processes. This research highlights the critical interactions between river systems and their implications for the evolution of the Amazon basin, especially regarding sediment contributions from various geological sources. Even though the Xingu River drains cratonic regions at higher elevations, the geochemistry of the bottom sediments confirms that the bedload is derived from heterogeneous sources with primarily intermediate igneous compositions and has undergone substantial recycling during river transport.

The Amazon reef system harbors a large proportion of the fish diversity known for the SW Atlantic, including some critical fishery resources, such as the Southern Red Snapper, Lutjanus purpureus, that thrives in the Great Amazon Reef System (GARS). Brazilian exports of L. purpureus result in millions of dollars every year, being socio-economically relevant at northern Brazil. Its capture is largely associated with the GARS. On the other hand, its regional abundance is attributed to the productivity of the area, which is, in turn, the result of the Amazon River plume (ARP). Thus, its trophodynamics is rather complex and important to understand the ARP-GARS linkage. The aim of the present study was to evaluate the trophic ecology of this fish and the possible influences of the nutrients from the ARP. To this end, gut microbiome and stable isotopic profiling of the gut and muscles of L. purpureus were performed. Fish samples were collected at two different stations (S8, S10) at different distances from the coast. The isotopic composition (δ13C and δ15N) of the fish tissues shows the influence of the river plume (particulate and dissolved), suggesting a substantial contribution of continental organic matter to L. purpureus food items. A total of ten 16S rRNA illumina libraries were obtained from the gut contents (546,301 sequences). The presence of picoplanktonic plume microbes (Synechococcus, Cyanobium, SAR324, Blastopirellula, Vibrio) in the gut microbiome of L. purpureus reinforces the influence of the river plume on the diet of this fish. Fluxes from the Amazon Forest and river nutrients which reach the ocean may indirectly contribute to the nutrition of L. purpureus through the food web by fueling its invertebrates and fish preys.

After successful invasions in the Caribbean and Mediterranean, lionfish (Pterois spp.) have recently invaded another important biogeographical region -the Brazilian Province. In this article, we discuss this new invasion, focusing on a roadmap for urgent mitigation of the problem, as well as focused research and management strategies. The invasion in Brazil is already in the consolidation stage, with 352 individuals recorded so far (2020-2023) along 2766 km of coastline. This includes both juveniles and adults, including egg-bearing females, ranging in length from 9.1 to 38.5 cm. Until now, most of the records in the Brazilian coast occurred in the equatorial southwestern Atlantic (99%), mainly on the Amazon mesophotic reefs (15% of the records), northeastern coast of Brazil (45%), and the Fernando de Noronha Archipelago (41%; an UNESCO World Heritage Site with high endemism rate). These records cover a broad depth range (1-110 m depth), twelve protected areas, eight Brazilian states (Amapá, Pará, Maranhão, Piauí, Ceará, Rio Grande do Norte, Paraíba, and Pernambuco) and multiple habitats (i.e., mangrove estuaries, shallow-water and mesophotic reefs, seagrass beds, artificial reefs, and sandbanks), indicating a rapid and successful invasion process in Brazilian waters. In addition, the lack of local knowledge of rare and/or cryptic native species that are potentially vulnerable to lionfish predation raises concerns regarding the potential overlooked ecological impacts. Thus, we call for an urgent integrated approach with multiple stakeholders and solution-based ecological research, real-time inventories, update of environmental and fishery legislation, participatory monitoring supported by citizen science, and a national and unified plan aimed at decreasing the impact of lionfish invasion. The experience acquired by understanding the invasion process in the Caribbean and Mediterranean will help to establish and prioritize goals for Brazil.

The geomorphological aspects of coastal environments are influenced by the sea level variation, sediment supply, waves, tides, currents, river discharge, and tectonic evolution. In some cases, tectonic events that occurred millions of years ago still control the morpho- and hydrodynamics of modern depositional environments. The Mocajuba estuary is in the northeastern sector of the Brazilian Amazon coast, where the Amazon River Plume (ARP) provides offshore suspended sediment concentrations (SSC) substantially higher than those provided by the Mocajuba River itself. The aim of this study was to analyze the morphology and SSC dynamics of a tropical tide-dominated estuary, formed by small-scale tectonic faults. Morphology, hydrodynamics, and SSC were measured during spring tides of rainy and dry seasons of two different years. The morphology was assessed via bathymetric surveys. Vertical profiles of depth, salinity, and SSC were collected using a CTD + turbidity sensor. Current velocity and discharge were evaluated on an ADCP transect occupied for 13 h at 20 km from the mouth. The water level variation was measured with five pressure sensor/tidal gauges along the estuary. The Mocajuba estuary is a tide-dominated estuary, with peculiar morphology aspects, such as rectilinear areas instead of the funnel-shaped morphology. Furthermore, due to the structural evolution and the faults caused by the tectonic events, the Mocajuba is a deep estuary, presenting an estuarine circulation similar to fjord systems. The combination between the inherited morphology and hydrodynamics aspects allows the tidal wave propagates without substantial deformation characterizing the synchronous behavior. The seasonal conditions influenced the salinity and SSC data along the estuary. While the salinity levels were higher during the dry season, the SSC was higher during the rainy season. In both seasons, we noticed the influence of the ARP providing fine sediments to the estuary and mangroves adjacent areas. In contrast to other Amazonian estuaries, the Mocajuba estuary does not present an estuarine turbidity maxima zone due to the high deep areas, low current velocities, and low SSC. Nevertheless, a “turbid wedge” was formed near the estuary mouth.

The microbiome is fundamental for understanding bacterial activities in sediments. However, only a limited number of studies have addressed the microbial diversity of Amazonian sediments. Here, we studied the microbiome of sediments from a 13,000-year BP core retrieved in a floodplain lake in Amazonia using metagenomics and biogeochemistry. Our aim was to evaluate the possible environmental influence over a river to a lake transition using a core sample. To this end, we sampled a core in the Airo Lake, a floodplain lake in the Negro River basin. The Negro River is the largest tributary of the Amazon River. The obtained core was divided into three strata: (i) surface, almost complete separation of the Airo Lake from the Negro River when the environment becomes more lentic with greater deposition of organic matter (black-colored sediment); (ii) transitional environment (reddish brown); and (iii) deep, environment with a tendency for greater past influence of the Negro River (brown color). The deepest sample possibly had the greatest influence of the Negro River as it represented the bottom of this river in the past, while the surface sample is the current Airo Lake bottom. In total, six metagenomes were obtained from the three different depth strata (total number of reads: 10.560.701; sequence length: 538 ± 24, mean ± standard deviation). The older (deeper) sediment strata contained a higher abundance of Burkholderia , Chitinophaga , Mucilaginibacter , and Geobacter , which represented ~ 25% of the metagenomic sequences. On the other hand, the more recent sediment strata had mainly Thermococcus , Termophilum , Sulfolobus , Archaeoglobus , and Methanosarcina (in total 11% of the metagenomic sequences). The sequence data were binned into metagenome-assembled genomes (MAGs). The majority of the obtained MAGs ( n = 16) corresponded to unknown taxa, suggesting they may belong to new species. The older strata sediment microbiome was enriched with sulfur cycle genes, TCA cycle, YgfZ, and ATP-dependent proteolysis in bacteria. Meanwhile, serine-glyoxylate cycle, stress response genes, bacterial cell division, cell division-ribosomal stress protein cluster, and oxidative stress increased in the younger strata. Metal resistance and antimicrobial resistance genes were found across the entire core, including genes coding for fluoroquinolones, polymyxin, vancomycin, and multidrug resistance transporters. These findings depict the possible microbial diversity during the depositional past events and provided clues of the past microbial metabolism throughout time.

Estuaries along the Amazonian coast are subjected to both a macrotidal regime and seasonally high fluvial discharge, both of which generate complex circulation. Furthermore, the Amazon River Plume (ARP) influences coastal circulation and suspended sediment concentrations (SSCs). The Gurupi estuary, located south of the mouth of the Amazon River, is relatively unstudied. This study evaluates how the Gurupi estuary dynamics respond to seasonal discharge and the varying influence of the ARP using cross-sectional and longitudinal surveys of morphology, hydrodynamics, and sediment transport. The Gurupi was classified as a tide-dominated estuary based on morphology and mean hydrodynamic conditions. However, the estuary was only partially mixed during both the wet and dry seasons. The tides propagated asymmetrically and hypersynchronously, with flood dominance during the dry season and ebb dominance during the rainy season. Seasonal variations of the ARP did not significantly affect the hydrodynamic structure of the lower Gurupi estuary. Estuarine turbidity maxima (ETM) were observed in both seasons, although the increase in fluvial discharge during the wet season attenuated and shifted the ETM seaward. Little sediment was delivered to the estuary by the river, and the SSCs were higher at the mouth in both seasons. Sediment was strongly imported during the dry season by tidal asymmetry. The morphology, hydrodynamics, and sediment dynamics all highlight the importance of considering both fluvial discharge and coastal influences on estuaries along the Amazon coast.

The Brazilian Amazon coast is characterized by macrotides, abundant rainfall, and low relief. A wide coastal plain, including impressive mangrove forests, have developed. The substantial sediment supply from the continental shelf has gradually filled the estuaries, especially where the fluvial discharge is particularly low, such as the Taperaçu estuary. In this estuary the, still ongoing, infilling process is remarkable, and its uppermost portion is already converted to wetlands. This study investigated this infilling process, based on sediment cores, sub-bottom profiles, and topography. The cores and profiles indicate mixed, often interlayered, fine sand and mud sedimentation associated with tidal circulation and sandy estuarine channel/muddy tidal flat combination. Moreover, a significant disparity in age was identified within the Quaternary sediment deposit, indicating that the filling consists of two distinct layers comprising Holocene and Pleistocene estuary-mangrove sediments. The Holocene mud includes usually the uppermost 5 m, and its base was dated in 7,595 ± 25 cal yrs BP, and its top is assumed to be recent. The Pleistocene envelop corresponds mostly to layers between 5 and 10 m beneath the surface, from which four datings exceed the method limit (43,500 cal yrs BP) and other four datings ranged from 33,457 ± 288 to 42,040 ± 480 cal yrs BP. The results have shown that, despite ages, all investigated mud layers correspond to a mangrove environment, under salt influence and low oxygen availability. The small local fluvial discharge reduced the incision/erosion and therefore increased the preservation potential during sea-level lowstands. The geochronology suggests that the Pleistocene infilling phase is related to the Marine Isotope Stage 3 (MIS 3), although the Sangamonian transgression (MIS 5) might be also involved. Results show that the infilling process of Amazonian estuaries is much more complex than usually assumed and that estuaries are sometimes not ephemerons, but episodic.

Sponges have co-evolved with microbes for over 400 myr. Previous studies have demonstrated that sponges can be classified according to the abundance of microbes in their tissues as Low Microbial Abundance (LMA) and High Microbial Abundance (HMA). While LMA sponges rely mainly on water column microbes, HMA appear to rely much more on symbiotic fermentative and autotrophic microbes maintained in their tissues. However, it is unclear if this pattern holds when comparing different species of tropical sponges under extreme nutrient conditions and sediment loads in the water column, such as the Great Amazon Reef System (GARS), which covers an area of ~56,000 km2 off the Amazon River mouth. Sponges are the major GARS benthic components. However, these sponges' microbiome across the GARS is still unknown. Here, we investigated water quality, isotopic values (δ13C and δ15N), metagenomic and lipidomic profiles of sponges obtained from different sectors throughout the GARS. >180 million shotgun metagenomic reads were annotated, covering 22 sponge species. Isotopic and lipidomic analyses suggested LMA sponges rely on the Amazon River Plume for nutrition. HMA sponges (N = 15) had higher Roseiflexus and Nitrospira abundance, whereas LMA sponges (N = 7) had higher Prochlorococcus and Pelagibacter abundance. Functional data revealed that the LMA sponge microbiomes had greater number of sequences related to phages and prophages as well as electron transport and photophosphorylation which may be related to photosynthetic processes associated with the Prochlorococcus and Synechococcus found in the LMA. The higher phages abundance in LMA sponges could be related to these holobionts' reduced defense towards phage infection. Meanwhile, HMA sponge microbiomes had higher Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR abundance, which may be involved in defense against phage infection. This study sheds light on the nutrient fluxes and microbes from the Amazon River plume into the sponge holobionts.

Continental margin sedimentation represents the terrestrial-marine geological transition. Coarser coastal sediments usually transition to fine-grained sediments across the shelf as the energy level decreases. As the distance from the continental source of terrigenous sediments increases, the mid-shelf mud belt transitions to a seaward organic/carbonatic sedimentation domain. However, this general pattern might change depending on the terrigenous sediment load. This is the case for the Amazon continental shelf, where the Amazon River empties and builds up the large Amazon River plume (ARP). The ARP promotes an inverse pattern with muddy nearshore prodelta sediments and siliciclastic sands offshore. This study investigates water and bottom characteristics to the east of the Amazon River mouth to understand the complex interplay that leads to simultaneous massive river plume spread and mesophotic reef development. Three cross-self profiles were performed, including physicalchemical water column measurements and bottom sample collection. The profiles were approximately 150 km apart, comprising a longitudinal gradient off of the ARP. The results reassure that there is enough light for mesophotic reefs to grow at the outer shelf and that at the mid-shelf, large-scale sand movement is likely to be the major limiting control on reef accretion. Also, mesophotic conditions (i.e., low light levels) occur in shallower waters, where a trend of reef expansion was identified, but high-energy levels and the lack of hard substrates hinder reef expansion.

OPINION article Front. Mar. Sci., 08 December 2022Sec. Marine Conservation and Sustainability Volume 9 - 2022 | https://doi.org/10.3389/fmars.2022.1088956