Seagrass Beds Research Articles

BIOMASSA DAN SIMPANAN KARBON PADA EKOSISTEM PADANG LAMUN DI WILAYAH NUSA LEMBONGAN

The Seagrass ecosystem is one of the important ecosystems in the ocean in mitigating global warming. This research aims to examine the potential for storing carbon stocks in seagrass biomass. The purposive sampling method was used at three location points. At each location, there are 9 quadrants for a total of 27 quadrants. The types of seagrass found were Thalassia hemprichii, Cymodocea rotundata, Enhalus acoroides, Halodule uninervis, Halophila ovalis, Halodule pinifolia with moderate diversity and moderate community stability. Seagrass conditions are relatively protected between the coast and coral reefs with the highest average density of 225 ind/m2. The type of seagrass with the highest density is Thalassia hemprichii. The types of substrates are sand, coral rubble, and sandy mud. The carbon stock in the Lembongan Beach area has an area of ??89.46 hectares of seagrass beds. Around 56.32% or 3,21 tons of carbon were stored as the bottom carbon stock of the substrate and 43.67% or 2,49 tons of carbon were stored as the top carbon stock of the substrate. Keywords: Thalassia Hemprichii, Seagrass, Substate, Global Warming

Limited potexvirus diversity in eastern Gulf of Mexico seagrass meadows.

Turtlegrass virus X, which infects the seagrass Thalassia testudinum, is the only potexvirus known to infect marine flowering plants. We investigated potexvirus distribution in seagrasses using a degenerate reverse transcription polymerase chain reaction (RT-PCR) assay originally designed to capture potexvirus diversity in terrestrial plants. The assay, which implements Potex-5 and Potex-2RC primers, successfully amplified a 584 nt RNA-dependent RNA polymerase (RdRp) fragment from TVX-infected seagrasses. Following validation, we screened 74 opportunistically collected, apparently healthy seagrass samples for potexviruses using this RT-PCR assay. The survey examined the host species T. testudinum, Halodule wrightii, Halophila stipulacea, Syringodium filiforme, Ruppia maritima, and Zostera marina. Potexvirus PCR products were successfully generated only from T. testudinum samples and phylogenetic analysis of sequenced PCR products revealed five distinct TVX sequence variants. Although the RT-PCR assay revealed limited potexvirus diversity in seagrasses, the expanded geographic distribution of TVX shown here emphasizes the importance of future studies to investigate T. testudinum populations across its native range and understand how the observed fine-scale genetic diversity affects host-virus interactions.

Shallow estuarine reef as nursery habitat for Australasian snapper (Chrysophrys auratus)

ABSTRACT Estuaries are important recruitment sites for many fish species, with structurally-complex habitats such as subtidal seagrass beds on soft sediments particularly valuable due to their provision of food and shelter. Soft sediments dominate most estuaries, but where hard-bottom reefs are present they have the potential to act as nursery habitats for juvenile fish. We document recruitment of juvenile Australasian snapper (Chrysophrys auratus) to a shallow linear sandstone reef in Whangateau Harbour, a small estuary in north-eastern New Zealand. Up to several hundred 0 + juveniles (∼20–70 mm fork length) were present on the reef during early summer to mid-late autumn each year from 2018 to 2021. Numbers were consistently highest at the seaward end of the reef, facing into incoming tidal currents, and lowest in the deeper central part of the reef, where larger, potentially cannibalistic, snapper were common. Juveniles disappeared from the reef fairly abruptly at the end of each season, with departure in at least two of the years appearing to follow a sudden decrease in water temperature rather than being associated with body size or absolute temperature. Although relatively small in area, estuarine reefs may be increasingly important nursery habitats in the future given the widespread loss of subtidal seagrass beds.

Disentangling the effect of space, time, and environmental and anthropogenic drivers on coastal macrobenthic β diversity in contrasting habitats over 15 years

Coastal zones are biodiversity hotspots and deliver essential ecosystem functions and services, yet they are exposed to multiple and interacting anthropogenic and environmental constraints. The individual and cumulative effects of these constraints on benthic communities, a key component of coastal ecosystems, and their variability across space and time, remains to be thoroughly quantified to guide conservation actions. Here, we explored how the presence of biogenic habitats influences the response of benthic communities to natural and anthropogenic constraints. We investigated this effect in both intertidal and subtidal habitats exposed to different pressures. We used data collected in the North-East Atlantic over 15 years (2005–2019) as part of the REBENT monitoring program, covering 38 sites of bare sediments, intertidal seagrass beds and maerl beds. We collected a range of environmental variables and proxies of anthropogenic pressures and used variation and hierarchical partitioning with redundancy analyses to estimate their relative effect on macrobenthic communities. We used descriptors modeling spatial and temporal structures (dbMEMs) to explore the scale of their effects and potential missing predictors. The selected variables explained between 53 % and 64 % of macrobenthic β diversity depending on habitat and depth. Fishing pressures, sedimentary and hydrodynamics variables stood out as the most important predictors across all habitats while proxies of anthropogenic pressures were overall more important in intertidal habitats. In the intertidal, presence of biogenic habitat strongly modulated the amount of explained variance and the identity of the selected variable. Across both tidal levels, analysis of models' residuals further indicated that biogenic habitats might mitigate the effect of extreme environmental events. Our study provides a hierarchy of the most important drivers of benthic communities across different habitats and tidal levels, emphasizing the prominence of anthropogenic pressures on intertidal communities and the role of biogenic habitats in mitigating environmental changes.

The Use of Photo-Biological Parameters to Assess the Establishment Success of Posidonia oceanica Cuttings after Transplantation

Seagrass meadows are increasingly threatened by anthropogenic activities and climate change, necessitating restoration efforts such as cutting transplantation. Understanding the complex interactions between plant morphology and physiology is crucial for designing robust restoration strategies and assessing the success of transplantation and recovery processes. A pilot transplantation experiment with the Mediterranean seagrass Posidonia oceanica (L.) Delile was conducted in Northwestern Corsica (Calvi, France) to evaluate the feasibility of meadows degraded due to boat anchoring. The effects of the cuttings’ origin and transplanting depth were investigated. The establishment success of transplanted fragments was assessed by investigating the photo-physiological parameters, carbohydrate content, and biometric parameters of both transplanted and control plants one year after transplantation at depths of 20 and 28 m. After one year, there was a high survival rate (90%) of the transplants, but their leaf surface area and biomass were significantly reduced compared to the control plants. Photosynthetic activity remained consistent between both depths, emphasizing the ability of P. oceanica cuttings to acclimate to a new light environment in a relatively short period of time (<3 months). Furthermore, light-harvesting pigments, photoprotective pigments, and carbohydrate concentration were greater at the deeper sites. This implies that transplantation at greater depths might be more effective. Furthermore, additional research is necessary to enhance our understanding of the relationship between photosynthesis and the overall health of the plant. This study emphasizes the essential integration of morphological and physiological investigations to offer an ecologically meaningful understanding of how marine ecosystems respond to various restoration methods.

Seagrasses on the move: Tracing the multi-decadal species distribution trends in lagoon meadows using Landsat imagery

Seagrass meadows play a vital role for lagoon ecosystems and their biota, sustaining multiple ecosystem services. Their distribution and functioning are closely tied to the environmental pressures induced by global changes. Long-term monitoring of seagrass species and communities is, hence, important to depict their response to past and future scenarios. The availability of long term open-access satellite data offers a new remote sensing perspective for monitoring seagrass communities dynamics in shallow waters, especially when combined with machine learning algorithms. In this study, seasonal multispectral images (from 1999 to 2019) were collected from Landsat 5 Thematic Mapper and 8 Operational Land Imager satellites to map the seagrass meadows, at the community and species levels, within the vast Grado and Marano lagoon (Northeast Italy) using a Random Forest (RF) algorithm. RF models were calculated using an extensive field training dataset collected in 2010 (n = 426) and reached an overall accuracy of 0.92 and 0.76 for the classification at the community and species levels, respectively. The change detection analysis revealed an increase of 14.16 km2 (+ 39%) of the whole seagrass community cover over the period, at a rate of 1.59 km2year−1. Despite the coarse spatial resolution (30 m) of the Landsat's images, the classification of seagrasses at species level achieved a good overall accuracy (0.76), evidencing Nanozostera noltei as the species with the highest cover increase (+13.87 km2 over the time period). The observed expansion is likely caused by an increase of the sea water influence that is radically modifying Adriatic brackish water bodies, emphasizing the connection between the ongoing environmental changes and the rapid responses of seagrass meadows.

Water column oxygenation by Posidonia oceanica seagrass meadows in coastal areas: A modelling approach

BackgroundSeagrass meadows are among the most abundant marine coastal ecosystems in the world. The wide variety of species, a worldwide distribution with overall high abundance, and especially their high productivity make them a plausible nature-based blue carbon solution to mitigate atmospheric CO2 levels. In the Mediterranean Basin, the endemic angiosperm Posidonia oceanica plays a remarkable role as a marine habitat provider in shallow waters through its vertical growth and as a carbon sink storing allochthonous carbon and biomass underneath the meadows. ObjectivesHere, we assess the capacity of a pristine meadow to oxygenate the water column in the coastal area of the Balearic Islands through an evaluation of the metabolic rates in the benthic compartment as well as the resulting oxygen concentrations in the pelagic compartment. MethodsGross primary production (GPP), respiration (R), and net community production (NCP) are determined from dissolved oxygen (DO) measurements using two different calculation methods: a model developed for this purpose is used for data obtained from water column sensors and benthic multiparametric sensors, whereas the mass balance of measured DO is used to calculate the metabolic rates inside benthic chambers. ResultsThe meadow at our study site was characterised as a net autotrophic ecosystem throughout the year. Oxygen productivity was significantly higher in the benthic compartment than in the water column and followed clear seasonal patterns, with enhanced productivity during spring. NoveltyThis work shows the key role of a healthy Posidonia oceanica ecosystem as a water column oxygenator by comparing primary production using three different sampling strategies. The potential of the seagrass as climate change mitigator and its importance for the Mediterranean coasts should be considered in future coastal planning strategies.

Potential of Organic Carbon Pool in the Ocean: Approaches for Naturally and Artificially Capturing and Retaining Carbon

Abstract The organic carbon stored in the seas and coastal ecosystems is referred to as “blue carbon.” Studies on blue carbon have focused a lot of emphasis on ocean ecosystems such seagrass beds, mangroves, saltmarshes, and algae beds. However, these vegetated ecosystems are not the exclusive repositories of atmospheric carbon, and alternative methods of capturing and retaining carbon naturally (by utilizing the inherent capacity of the ocean) and artificially (through the implementation of engineered approaches) are thus being investigated. This study provides an overview of these approaches and assesses the potential for storing organic carbon beyond vegetated ecosystems. The study used a systematic evaluation of the literature in order to determine the trend in blue carbon research, particularly with regard to carbon storage beyond vegetated environments. Besides the carbon sequestration by the marine vegetation, the present study proposes the feasibility of capturing aquatic carbon through a biological pump process that has the potential to store carbon at the ocean floor. Furthermore, we summarize the potential impact of artificial processes on carbon dioxide removal. This study suggests an expanded definition of “blue carbon” that incorporates the concepts of “organic carbon,” “carbon dioxide removal,” and “carbon capture and storage by oceans and coastal ecosystems.”

Eating Habits and Dietary Strategies of the Glass Perchlet Fish (Ambassis macracanthus) In Benoa Bay Waters, Bali in Two Different Seasons

The Benoa Bay area and its surroundings are a center of biodiversity at the ecosystem level in the southern coastal region of Bali. This area exhibits diverse ecosystems, including mangrove ecosystems, coral reefs, seagrass beds, and tidal flats. This research aims to analyze and describe the feeding ecology of Ambassis macracanthus in the waters of Benoa Bay. The study was conducted in May, at the end of the transitional season, and in July and August, during the eastern monsoon season in Benoa Bay Waters. Modified gill nets with mesh sizes of 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 cm were used for capturing the fish. The fish were caught at three stations, which represented the characteristic conditions of the Benoa Bay Waters. Out of the 396 individuals caught during the study, only 100 were selected for examination. The average relative fullness gut index (RGI) of Ambassis macracanthus ranged from 0.39 to 0.67. The total Important Relative Index (IRI) value for the food of Ambassis macracanthus in Benoa Bay Waters was 951.27. Ambassis macracanthus in Benoa Bay Waters is an omnivorous species with a tendency towards herbivory, and 21 different organisms were found in its diet, including three classes of phytoplankton and three classes of zooplankton. The feeding strategy developed by Ambassis macracanthus in Benoa Bay Waters is generalist. This information about the fish can be used as a fundamental basis for managing fish in the waters of Benoa Bay.

Monitoring an Ecosystem in Crisis: Measuring Seagrass Meadow Loss Using Deep Learning in Mosquito Lagoon, Florida

Monitoring an Ecosystem in Crisis: Measuring Seagrass Meadow Loss Using Deep Learning in Mosquito Lagoon, Florida

Physiological and multi-omics analysis reveals the influence of copper on Halophila beccarii Asch

High concentrations of copper can pollute coastal waters, primarily from agricultural runoff and mining activities, which can harm marine organisms, including seagrasses. The molecular mechanism of copper toxicity to seagrass currently remains unclear. To determine the response to copper, physiological and multi-omic analyses were conducted to explore the molecular mechanism by which copper affects the global threatened seagrass Halophila beccarii Asch. Excessive copper stress causes oxidative damage and stimulates the activity of the antioxidant enzyme system to remove excess reactive oxygen species (ROS), thereby reducing the damage caused by copper stress. Cu increases the activities of superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11), glutathione peroxidase (EC 1.11.1.9), ascorbate oxidase (EC 1.10.3.3), glutathione reductase (EC 1.6.4.2), and dehydroascorbate reductase (EC 1.8.5.1) and the content of malondialdehyde and reduces the activity of monodehydroascorbate reductase (EC 1.6.5.4). Under copper stress, H. beccarii upregulates the metabolic pathways of steroid biosynthesis and cutin, suberin, and wax biosynthesis, downregulates the metabolic pathways of arginine and proline metabolism and fructose and mannose metabolism; the levels of expression of the ribosome-related genes; upregulates the levels of expression of circadian rhythm-related proteins and downregulates the levels of glutathione metabolism and the proteins related to carbon fixation. This study provides new insights into the response of seagrass to copper stress and reports potential candidate metabolites, genes, and proteins that can be considered as biomarkers to improve the protection and management of seagrass meadows.

Flood effects on estuarine fish are mediated by seascape composition and context

Estuaries are crucial feeding, nursery and resting sites for fish but can also be subject to the impacts of severe flooding. The environmental features of estuaries can mediate how they respond to these impacts. For example, the size, configuration, and context of estuarine habitats across seascapes affects the value of patches for fish, and so fish assemblages at sites with a greater habitat extent or closer to the mouth of an estuary may rebound more quickly from flooding. We investigated how a once in 100-year flood event affected fish assemblages at approximately 600 sites across 13 estuaries and six estuarine habitats (bare sediments, log snags, mangrove forests, rocky structures, saltmarsh and seagrass meadows) in southeast Queensland, Australia, and determined whether flood impacts were mediated by the position of sites within the broader estuarine seascape. Sites were surveyed annually in 2020/2021 (pre-flood) and 2022 (6 months post-flood) using underwater videography. Flooding modified the structure of the fish community and reduced the abundance of fish targeted by local fisheries in all six habitats. Crucially, flood effects on fish were greater at sites near more expansive urbanisation in some ecosystems, but lower at sites nearer to the estuary mouth. Maximising the extent of natural habitats across estuaries can mediate the effects of floods and should be priorities for restoration and management plans seeking to maintain biodiversity and fisheries productivity in the face of increasing climate-related disturbances.

Carbon and nitrogen deposits of macroalgal origin on a tropical seagrass meadow

Carbon and nitrogen deposits of macroalgal origin on a tropical seagrass meadow

Seagrass decline weakens sediment organic carbon stability

Seagrass meadows are globally recognized as critical natural carbon sinks, commonly known as ‘blue carbon’. However, seagrass decline attributed to escalating human activities and climate change, significantly influences their carbon sequestration capacity. A key aspect in comprehending the impact of seagrass decline on carbon sequestration is understanding how degradation affects the stored blue carbon, primarily consisting of sediment organic carbon (SOC). While it is widely acknowledged that seagrass decline affects the input of organic carbon, little is known about its impact on SOC pool stability. To address this knowledge, we examined variations in total SOC and recalcitrant SOC (RSOC) at a depth of 15 cm in nine seagrass meadows located on the coast of Southern China. Our findings revealed that the ratio of RSOC to SOC (RSOC/SOC) ranged from 27 % to 91 % in the seagrass meadows, and the RSOC/SOC increased slightly with depth. Comparing different seagrass species, we observed that SOC and RSOC stocks were 1.94 and 3.19-fold higher under Halophila beccarii and Halophila ovalis meadows compared to Thalassia hemprichii and Enhalus acoroides meadows. Redundancy and correlation analyses indicated that SOC and RSOC content and stock, as well as the RSOC/SOC ratio, decreased with declining seagrass shoot density, biomass, and coverage. This implies that the loss of seagrass, caused by human activities and climate change, results in a reduction in carbon sequestration stability. Further, the RSOC decreased by 15 %, 29 %, and 40 % under unvegetated areas compared to adjacent Halophila spp., T. hemprichii and E. acoroides meadows, respectively. Given the anticipated acceleration of seagrass decline due to climate change and increasing coastal development, our study provides timely information for developing coastal carbon protection strategies. These strategies should focus on preserving seagrass and restoring damaged seagrass meadows, to maximize their carbon sequestration capacity.

Eelgrass meadow response to heat stress. II. Impacts of ocean warming and marine heatwaves measured by novel metrics

In June 2015, a marine heatwave triggered a severe eelgrass Zostera marina die-off event at the Virginia Coast Reserve (USA), followed by a slow and spatially heterogeneous recovery. We investigated the effects of heat stress on seagrass loss and recovery. Using hourly summer water temperature measurements from 2016-2020, we developed a novel approach to quantifying the stress of ocean warming on seagrass meadows. We defined 2 metrics: cumulative heat stress (as heating degree-hours, HDHs) and heat stress relief (as cooling degree-hours, CDHs), relative to a 28.6°C eelgrass ecosystem thermal tolerance threshold previously determined at this site from aquatic eddy covariance measurements. These metrics were compared to spatiotemporal patterns of summertime eelgrass shoot density and length. We found that the healthiest parts of the meadow benefited from greater heat stress relief (2-3×) due to tidal cooling (inputs of cooler ocean water through ocean inlets) during warm periods, resulting in ~65% higher shoot densities compared to the center of the meadow, which experienced higher heat stress (2×) and less relief. We also calculated the amount of heat stress preceding the eelgrass die-off in summer 2015, and found that this event was triggered by a cumulative heat stress of ~100-200°C-hours during the peak growing season. Sulfur isotope analyses of eelgrass leaves and sediment also suggested that sulfide toxicity likely contributed to eelgrass decline. Overall, our metrics incorporate physiological heat tolerances with the duration and intensity of heat stress and relief, and thus lay the groundwork for forecasting seagrass meadow vulnerability and resilience to future warming oceans.

Systematic histology and evidence for the male reproductive activity of Amphibalanus amphitrite (Darwin, 1854)

AbstractThe striped acorn barnacle, Amphibalanus amphitrite, a taxon of Balanidae, is commonly found along Thailand's coastline. In this study, we used histological methods to describe the microscopic anatomy of A. amphitrite. All samples (n = 30) were obtained from the seagrass beds of Libong Island, Thailand, in the Andaman Sea. Histological observation of various longitudinal sections from specimens of A. amphitrite provides clear insights into the organization of organ systems in the species. The digestive tract was observed to be mainly divided into four subregions, including the cuticle‐lined mouth and esophagus, which is characterized by a high columnar epithelium, the stomach, and the intestine. The accessory organ, including the digestive gland, exhibited lobulated structures and was covered with low columnar epithelial cells on a thin layer of smooth muscle. Furthermore, we examined the reproductive system, including both the ovary and testes, as well as the process of gametogenesis. Testicular development was predominantly observed during active breeding seasons throughout the observation.

Occurrence and distribution of antibiotic pollution and antibiotic resistance genes in seagrass meadow sediments based on metagenomics

Seagrass meadows are one of the most important coastal ecosystems that provide essential ecological and economic services. The contamination levels of antibiotic and antibiotic resistance genes (ARGs) in coastal ecosystems are severely elevated owing to anthropogenic disturbances, such as terrestrial input, aquaculture effluent, and sewage discharge. However, few studies have focused on the occurrence and distribution of antibiotics and their corresponding ARGs in this habitat. Thus, we investigated the antibiotic and ARGs profiles, microbial communities, and ARG-carrying host bacteria in typical seagrass meadow sediments collected from Swan Lake, Caofeidian shoal harbor, Qingdao Bay, and Sishili Bay in the Bohai Sea and northern Yellow Sea. The total concentrations of 30 detected antibiotics ranged from 99.35 to 478.02 μg/kg, tetracyclines were more prevalent than other antibiotics. Metagenomic analyses showed that 342 ARG subtypes associated with 22 ARG types were identified in the seagrass meadow sediments. Multidrug resistance genes and RanA were the most dominant ARG types and subtypes, respectively. Co-occurrence network analysis revealed that Halioglobus, Zeaxanthinibacter, and Aureitalea may be potential hosts at the genus level, and the relative abundances of these bacteria were higher in Sishili Bay than those in other areas. This study provided important insights into the pollution status of antibiotics and ARGs in typical seagrass meadow sediments. Effective management should be performed to control the potential ecological health risks in seagrass meadow ecosystems.

The Complete Mitochondrial Genome of the Chemosymbiotic Lucinid Bivalve Pillucina pisidium (Dunker, 1860) Occurring in Seagrass Zostera marina Bed in a Lagoon in Jeju Island, Korea

Commonly found in tropic and subtropic seagrass beds, lucinid clams host sulfur-oxidizing bacteria within their gills. These symbionts are crucial in converting phytotoxic sulfide in the sediment into less harmful sulfate, thus enhancing the environment for seagrasses and associated biota. We recently uncovered small clams within a Zostera marina seagrass bed situated in a lagoon on Jeju Island, off the south coast of Korea. These bivalves, with shell lengths of up to 7 mm, exhibited distinct features, including thick and hypertrophied gills, inflated and ovoid shells with a shell height/shell length ratio of 0.99, and the absence of a sulcus on the external shell surface. These characteristics align closely with those of Pillucina pisidium, a lucinid clam species originally reported in Japan. Analysis of the cytochrome b gene partial sequences of the clams from Jeju Island revealed a 100% match with P. pisidium reported in Japan, confirming their identity. Moreover, we successfully assembled the complete mitochondrial genome of P. pisidium for the first time, revealing a circular genome spanning 21,059 bp. Additionally, we constructed a phylogenetic tree using 13 protein-coding genes (PCGs) extracted from the mitochondrial genome of P. pisidium. Notably, P. pisidium formed a distinct clade within the subclass Autobranchia alongside other lucinid clams in the phylogenetic tree. However, within the family Lucinidae, synteny analysis of the 13 PCGs revealed diverse gene arrangement patterns, indicating considerable divergence. This divergence underscores the need for an extensive examination of Lucinidae mitochondrial genomes to elucidate the phylogenetic ties more precisely within the family, highlighting P. pisidium’s distinct evolutionary path within the family Lucinidae.

Characterizing Spatial and Temporal Trends in Net Sediment Accumulation in Seagrass Meadows

Seagrass meadows are known as hot spots for carbon accumulation, but there is limited field data on the variability of sediment accumulation across time and space. We developed a method to assess spatial and temporal heterogeneity in net sediment accumulation in seagrass meadows using small, inexpensive samplers, allowing for over 200 unique measurements across multiple transects within our study site. Using this method, we assessed sediment accumulation across seagrass meadow edges, and in varying weather conditions. We found the greatest accumulation of sediment 5 m outside of seagrass meadow edges, with sediment accumulation rates averaging just under 100 g m−2 day−1, though rates were highly variable. Carbon accumulation from settled sediment was generally greater outside of seagrass meadow edges than within the bed, especially at sites undergoing recent expansion. Measurements made during tropical storms showed both scouring of sediment away from sites, and increased accumulation, depending on site properties as well as individual tropical storm characteristics. In the storm that had a measurable storm surge, scouring of sediment was a more dominant mechanism, whereas deposition dominated in the storm that had high winds but no associated storm surge. Our data demonstrate the necessity of including measurements that characterize both spatial and meteorological variability to develop a more holistic understanding of the movement of sediment and particulate organic carbon associated with seagrass meadows, especially as meadow area becomes increasingly fragmented with human activity and global change.

Updating and validating seagrass ecosystem knowledge in the gulf of California: a comprehensive review

Seagrasses are globally acknowledged as crucial habitats as they provide a variety of ecosystem services. Mexico’s legislation protects most of these marine plants; however, the protection often fails in application. The Gulf of California, despite being a biodiversity hotspot, has scant data on seagrasses. Here, human activity and climate change increasingly threaten these coastal ecosystems, with conservation and research efforts lacking coordination at a regional level. Our manuscript aimed to review and standardize existing data on Gulf of California seagrass species, ensuring open access for data updates; pinpointing conservation deficiencies; and guiding future research. We have added new records to the official public data, but we were able to recapture only 25% of the seagrass locations meaning a potential reduction in their historical distribution of 45.8%. Even though Mexico’s legislation protects some species of seagrasses, it protection often fails in the application. We identified that only 6.1% of the seagrass locations are within protected areas that recognize their presence in their management plans (e.g., the Balandra Flora and Fauna Protected Area and the Upper Gulf of California and Colorado River Delta Biosphere Reserve). At least 55.9% of seagrass records are associated with potentially damaging activities like pollution, coastal modification or biological resources use, while 23% are exposed to higher frequency of marine heatwaves. Given the importance of seagrass meadows under Mexican law and their internationally recognized ecological value, sharing current information and guiding research is essential. Our study seeks to galvanize renewed research initiatives and raise more awareness on the conservation of the Gulf of California’s seagrasses.