The nameseagrass stems from the many species with long and narrowleaves, which grow byrhizome extension and often spread across large "meadows" resemblinggrassland; many species superficially resemble terrestrialgrasses of the familyPoaceae.
Like allautotrophic plants, seagrassesphotosynthesize, in the submergedphotic zone, and most occur in shallow and sheltered coastal waters anchored in sand or mud bottoms. Most species undergo submarinepollination and complete their life cycle underwater. While it was previously believed this pollination was carried out without pollinators and purely by sea current drift, this has been shown to be false for at least one species,Thalassia testudinum, which carries out a mixed biotic-abiotic strategy. Crustaceans (such as crabs,Majidae zoae,Thalassinidea zoea) andsyllidpolychaete worm larvae have both been found with pollen grains, the plant producing nutritious mucigenous clumps of pollen to attract and stick to them instead of nectar as terrestrial flowers do.[2]
Seagrasses form dense underwaterseagrass meadows which are among the most productive ecosystems in the world. They function as importantcarbon sinks[3] and provide habitats and food for a diversity ofmarine life comparable to that ofcoral reefs.
Seagrasses are a paraphyletic group of marineangiosperms which evolvedin parallel three to four times from land plants back to the sea. The following characteristics can be used to define a seagrass species:
The roots can live in ananoxic environment and depend on oxygen transport from the leaves and rhizomes but are also important in thenutrient transfer processes.[4][5]
Seagrasses profoundly influence the physical, chemical, and biological environments of coastal waters.[4] Though seagrasses provide invaluableecosystem services by acting as breeding and nursery ground for a variety of organisms and promotecommercial fisheries, many aspects of their physiology are not well investigated. There are 26 species of seagrasses in North American coastal waters.[6] Several studies have indicated that seagrass habitat is declining worldwide.[7][8] Ten seagrass species are at elevated risk of extinction (14% of all seagrass species) with three species qualifying asendangered. Seagrass loss and degradation of seagrassbiodiversity will have serious repercussions for marine biodiversity and the human population that depends upon the resources and ecosystem services that seagrasses provide.[9][4]
Seagrasses form importantcoastal ecosystems.[10] The worldwide endangering of these sea meadows, which provide food and habitat for manymarine species, prompts the need for protection and understanding of these valuable resources.[11]
Evolution of seagrass, showing the progression onto land from marine origins, the diversification of land plants and the subsequent return to the sea by the seagrasses
Around 140 million years ago, seagrasses evolved from early monocots which succeeded in conquering the marine environment.[11]Monocots are grass and grass-likeflowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf orcotyledon.[12]
Terrestrial plants evolved perhaps as early as 450 million years ago from a group ofgreen algae.[13] Seagrasses then evolved from terrestrial plants which migrated back into the ocean.[14][15] Between about 70 million and 100 million years ago, three independent seagrass lineages (Hydrocharitaceae,Cymodoceaceae complex, andZosteraceae) evolved from a single lineage of themonocotyledonous flowering plants.[16]
Other plants that colonised the sea, such assalt marsh plants,mangroves, andmarine algae, have more diverse evolutionary lineages. In spite of their low species diversity, seagrasses have succeeded in colonising the continental shelves of all continents except Antarctica.[17]
Genome information has shown further that adaptation to the marine habitat was accomplished by radical changes incell wall composition.[18][19] However the cell walls of seagrasses are not well understood. In addition to theancestral traits ofland plants one would expect habitat-driven adaptation process to the new environment characterized by multipleabiotic (high amounts of salt) andbiotic (different seagrass grazers and bacterial colonization) stressors.[11] The cell walls of seagrasses seem intricate combinations of features known from both angiosperm land plants and marine macroalgae with new structural elements.[11]
Today, seagrasses are a polyphyletic group of marine angiosperms with around 60 species in five families (Zosteraceae,Hydrocharitaceae,Posidoniaceae,Cymodoceaceae, andRuppiaceae), which belong to the order Alismatales according to theAngiosperm Phylogeny Group IV System.[20] The genusRuppia, which occurs in brackish water, is not regarded as a "real" seagrass by all authors and has been shifted to the Cymodoceaceae by some authors.[21] TheAPG IV system and The Plant List Webpage[22] do not share this family assignment.[11]
The familyZosteraceae, also known as theseagrass family, includes two genera containing 14 marine species. It is found intemperate andsubtropicalcoastal waters, with the highest diversity located around Korea and Japan.
The familyHydrocharitaceae, also known astape-grasses, includeCanadian waterweed and frogbit. The family includes both fresh and marine aquatics, although of the sixteen genera currently recognised, only three are marine.[23] They are found throughout the world in a wide variety of habitats, but are primarily tropical.
The familyPosidoniaceae contains a single genus with two to nine marine species found in the seas of theMediterranean and around the south coast ofAustralia.
Seagrasscell walls contain the samepolysaccharides found inangiosperm land plants, such ascellulose[25] However, the cell walls of some seagrasses are characterised bysulfated polysaccharides,[26][27] which is a common attribute ofmacroalgae from the groups ofred,brown and alsogreen algae. It was proposed in 2005 that the ability to synthesise sulfated polysaccharides was regained by marine angiosperms.[26] Another unique feature of cell walls of seagrasses is the occurrence of unusualpectic polysaccharides calledapiogalacturonans.[28][29][11]
In addition to polysaccharides,glycoproteins of thehydroxyproline-rich glycoprotein family,[30] are important components of cell walls of land plants. The highly glycosylatedarabinogalactan proteins are of interest because of their involvement in both wall architecture and cellular regulatory processes.[31][32] Arabinogalactan proteins are ubiquitous in seed land plants[32] and have also been found inferns,lycophytes andmosses.[33] They are structurally characterised by large polysaccharidemoieties composed ofarabinogalactans (normally over 90% of the molecule) which are covalently linked viahydroxyproline to relatively small protein/peptide backbones (normally less than 10% of the molecule).[32] Distinctglycan modifications have been identified in different species and tissues and it has been suggested these influence physical properties and function. In 2020, AGPs were isolated and structurally characterised for the first time from a seagrass.[34] Although the common backbone structure of land plant arabinogalactan proteins is conserved, the glycan structures exhibit unique features suggesting a role of seagrass arabinogalactan proteins inosmoregulation.[35][11]
Further components of secondary walls of plants are cross-linkedphenolic polymers calledlignin, which are responsible for mechanical strengthening of the wall. In seagrasses, this polymer has also been detected, but often in lower amounts compared to angiosperm land plants.[36][37][38][39][11] Thus, the cell walls of seagrasses seem to contain combinations of features known from both angiosperm land plants and marine macroalgae together with new structural elements. Dried seagrass leaves might be useful for papermaking or as insulating materials, so knowledge of cell wall composition has some technological relevance.[11]
Seagrasses have contrastingcolonisation strategies.[50] Some seagrasses formseed banks of small seeds with hardpericarps that can remain in the dormancy stage for several months. These seagrasses are generally short-lived and can recover quickly from disturbances by notgerminating far away fromparent meadows (e.g.,Halophila sp.,Halodule sp.,Cymodocea sp.,Zostera sp. andHeterozostera sp.).[50][51] In contrast, other seagrasses formdispersalpropagules. This strategy is typical of long-lived seagrasses that can form buoyant fruits with inner large non-dormant seeds, such as the generaPosidonia sp.,Enhalus sp. andThalassia sp.[50][52] Accordingly, the seeds of long-lived seagrasses have a large dispersal capacity compared to the seeds of the short-lived type,[53] which permits the evolution of species beyond unfavourable light conditions by the seedling development of parent meadows.[40]
The seagrassPosidonia oceanica (L.) Delile is one of the oldest and largest species on Earth. An individual can formmeadows measuring nearly 15 km wide and can be hundreds to thousands of years old.[54]P. oceanicameadows play important roles in the maintenance of thegeomorphology of Mediterranean coasts, which, among others, makes this seagrass a priority habitat of conservation.[55] Currently, the flowering and recruitment ofP. oceanica seems to be more frequent than that expected in the past.[56][57][58][59][60] Further, this seagrass has singular adaptations to increase its survival during recruitment. The large amounts of nutrient reserves contained in the seeds of this seagrass support shoot and root growth, even up to the first year of seedling development.[54] In the first months ofgermination, when leaf development is scarce,P. oceanica seeds performphotosynthetic activity, which increases their photosynthetic rates and thus maximises seedling establishment success.[61][62] Seedlings also show high morphological plasticity during theirroot system development[63][64] by forming adhesiveroot hairs to helpanchor themselves to rocky sediments.[56][65][66] However, many factors aboutP. oceanica sexual recruitment remain unknown, such as when photosynthesis in seeds is active or how seeds can remain anchored to and persist on substrate until their root systems have completely developed.[40]
Morphological and photoacclimatory responses of intertidal and subtidalZostera marina eelgrass[67]
Seagrasses occurring in the intertidal and subtidal zones are exposed to highly variable environmental conditions due to tidal changes.[68][69] Subtidal seagrasses are more frequently exposed to lower light conditions, driven by plethora of natural and human-caused influences that reduce light penetration by increasing the density of suspended opaque materials. Subtidal light conditions can be estimated, with high accuracy, using artificial intelligence, enabling more rapid mitigation than was available usingin situ techniques.[70] Seagrasses in theintertidal zone are regularly exposed to air and consequently experience extreme high and low temperatures, high photoinhibitoryirradiance, anddesiccation stress relative to subtidal seagrass.[69][71][72] Such extreme temperatures can lead to significant seagrass dieback when seagrasses are exposed to air during low tide.[73][74][75] Desiccation stress during low tide has been considered the primary factor limiting seagrass distribution at the upper intertidal zone.[76] Seagrasses residing the intertidal zone are usually smaller than those in the subtidal zone to minimize the effects of emergence stress.[77][74] Intertidal seagrasses also show light-dependent responses, such as decreased photosynthetic efficiency and increased photoprotection during periods of high irradiance and air exposure.[78][79]
In contrast, seagrasses in thesubtidal zone adapt to reduced light conditions caused by light attenuation and scattering due to the overlaying water column and suspended particles.[81][82] Seagrasses in the deep subtidal zone generally have longer leaves and wider leaf blades than those in the shallow subtidal or intertidal zone, which allows more photosynthesis, in turn resulting in greater growth.[72] Seagrasses also respond to reduced light conditions by increasingchlorophyll content and decreasing thechlorophyll a/b ratio to enhancelight absorption efficiency by using the abundant wavelengths efficiently.[83][84][85] As seagrasses in the intertidal and subtidal zones are under highly different light conditions, they exhibit distinctly different photoacclimatory responses to maximize photosynthetic activity and photoprotection from excess irradiance.[citation needed]
Seagrasses assimilate large amounts ofinorganic carbon to achieve high level production.[86][87] Marinemacrophytes, including seagrass, use both CO2 andHCO−3 (bicarbonate) for photosynthetic carbon reduction.[88][89][90] Despite air exposure during low tide, seagrasses in the intertidal zone can continue to photosynthesize utilizing CO2 in the air.[91] Thus, the composition of inorganic carbon sources for seagrass photosynthesis probably varies between intertidal and subtidal plants. Because stablecarbon isotope ratios of plant tissues change based on the inorganic carbon sources for photosynthesis,[92][93] seagrasses in the intertidal and subtidal zones may have different stable carbon isotope ratio ranges.
Seagrass beds/meadows can be either monospecific (made up of a single species) or in mixed beds. Intemperate areas, usually one or a few species dominate (like the eelgrassZostera marina in the North Atlantic), whereastropical beds usually are more diverse, with up to thirteenspecies recorded in thePhilippines.[citation needed]
Seagrass beds are diverse and productiveecosystems, and can harbor hundreds of associated species from allphyla, for example juvenile and adultfish,epiphytic and free-livingmacroalgae andmicroalgae,mollusks,bristle worms, andnematodes. Few species were originally considered to feed directly on seagrassleaves (partly because of their low nutritional content), but scientific reviews and improved working methods have shown that seagrassherbivory is an important link in the food chain, feeding hundreds of species, includinggreen turtles,dugongs,manatees,fish,geese,swans,sea urchins andcrabs. Some fish species that visit/feed on seagrasses raise their young in adjacentmangroves orcoral reefs.
Seagrasses trap sediment and slow down water movement, causing suspended sediment to settle out. Trapping sediment benefitscoral by reducing sediment loads, improving photosynthesis for both coral and seagrass.[94]
Although often overlooked, seagrasses provide a number ofecosystem services.[95][96] Seagrasses are consideredecosystem engineers.[97][15][14] This means that the plants alter the ecosystem around them. This adjusting occurs in both physical and chemical forms. Many seagrass species produce an extensive underground network of roots andrhizome which stabilizes sediment and reducescoastal erosion.[98] This system also assists in oxygenating the sediment, providing a hospitable environment forsediment-dwelling organisms.[97] Seagrasses also enhancewater quality by stabilizing heavy metals, pollutants, and excess nutrients.[99][15][14] The long blades of seagrasses slow the movement of water which reduces wave energy and offers further protection against coastalerosion andstorm surge. Furthermore, because seagrasses are underwater plants, they produce significant amounts of oxygen which oxygenate the water column. These meadows account for more than 10% of the ocean's total carbon storage. Per hectare, it holds twice as much carbon dioxide as rain forests and can sequester about 27.4 million tons of CO2 annually.[100]
Seagrass meadows provide food for many marine herbivores. Sea turtles, manatees, parrotfish, surgeonfish, sea urchins and pinfish feed on seagrasses. Many other smaller animals feed on the epiphytes and invertebrates that live on and among seagrass blades.[101] Seagrass meadows also provide physical habitat in areas that would otherwise be bare of any vegetation. Due to this three dimensional structure in the water column, many species occupy seagrass habitats for shelter and foraging. It is estimated that 17 species of coral reef fish spend their entire juvenile life stage solely on seagrass flats.[102] These habitats also act as a nursery grounds for commercially and recreationally valued fishery species, including the gag grouper (Mycteroperca microlepis), red drum,common snook, and many others.[103][104] Some fish species utilize seagrass meadows and various stages of the life cycle. In a recent publication, Dr. Ross Boucek and colleagues discovered that two highly sought after flats fish, the common snook andspotted sea trout provide essential foraging habitat during reproduction.[105] Sexual reproduction is extremely energetically expensive to be completed with stored energy; therefore, they require seagrass meadows in close proximity to complete reproduction.[105] Furthermore, many commercially importantinvertebrates also reside in seagrass habitats including bay scallops (Argopecten irradians),horseshoe crabs, andshrimp. Charismatic fauna can also be seen visiting the seagrass habitats. These species includeWest Indian manatee,green sea turtles, and various species of sharks. The high diversity of marine organisms that can be found on seagrass habitats promotes them as a tourist attraction and a significant source of income for many coastal economies along the Gulf of Mexico and in the Caribbean.
In 2022, scientists reported the discovery of the world’s largest known seagrass ecosystem, near the Bahamas.[106] The discovery was made with the help of tiger sharks who between 2016 and 2022 were tagged with cameras so that scientists could see the ocean floor from a different perspective.[107]
The most important interconnected processes within the seagrassholobiont are related to processes in the carbon, nitrogen and sulfur cycles.Photosynthetically active radiation (PAR) determines the photosynthetic activity of the seagrass plant that determines how much carbon dioxide is fixed, how muchdissolved organic carbon (DOC) is exuded from the leaves and root system, and how much oxygen is transported into therhizosphere. Oxygen transportation into the rhizosphere alters theredox conditions in the rhizosphere, differentiating it from the surrounding sediments that are usuallyanoxic andsulfidic.[108][109]
The concept of theholobiont, which emphasizes the importance and interactions of a microbial host with associated microorganisms and viruses and describes their functioning as a single biological unit,[110] has been investigated and discussed for many model systems, although there is substantial criticism of a concept that defines diverse host-microbe symbioses as a single biological unit.[111] The holobiont and hologenome concepts have evolved since the original definition,[112] and there is no doubt that symbiotic microorganisms are pivotal for the biology and ecology of the host by providing vitamins, energy and inorganic or organic nutrients, participating in defense mechanisms, or by driving the evolution of the host.[113]
Although most work on host-microbe interactions has been focused on animal systems such as corals, sponges, or humans, there is a substantial body of literature onplant holobionts.[114] Plant-associated microbial communities impact both key components of the fitness of plants, growth and survival,[115] and are shaped by nutrient availability and plant defense mechanisms.[116] Several habitats have been described to harbor plant-associated microbes, including the rhizoplane (surface of root tissue), therhizosphere (periphery of the roots), the endosphere (inside plant tissue), and thephyllosphere (total above-ground surface area).[108] These distinctions are due to the differences in how the biotic and abiotic factors interact with the plant as the community structure in anoxic sediments will differ from that in a dynamic water column.[117]
Mosy seagrass microbiome studies useZostera marina as the target species due to its wide distribution and substantial ecosystem services.[118] There is a general vertical shift in the microbial population in seagrasses withAlpha andGamma proteobacteria[119] dominating the upper leaf microenvironment whileDelta andGamma proteobacteria[120] are the primary phyla in the rhizosphere. While sharing phyla there are significant differences in above and belowground microbial communities on seagrass hosts. The functional roles of microbes in the regions are distinct. The consumption of waste products,[121][122] pathogen defense,[123] and epiphytic control[124] are primary roles on mature blades. Growth promoting characteristics from specialized taxa have endophytic representation in reproductive tissues and seeds.[125] Nitrogen fixation,[126] sulfur oxidation and compound management are the functions most associated with rhizosphere taxa in which fungal[127] and archaeal[128] OTUs (operational taxonomic units) also have representation.
The microbial community in thePosidonia oceanica rhizosphere shows similar complexity as terrestrial habitats that contain thousands of taxa per gram of soil. In contrast, the chemistry in the rhizosphere ofP. oceanica was dominated by the presence of sugars likesucrose andphenolics.[129]
There is current interest in the concept of a core seagrass microbiome. The concept faces challenges as there is no consensus on definition or quantification methods as the scale, objectives and resolution of a study vary with research and analysis.[130] Overarchingly it is defined as a consistent set of microbial taxa associated with a given host.[131] Seagrass literature has been interested in defining core microbiomes across populations, species, genera, and geographical regions. The findings are in contention with support for[132] and against[133][134] the theory of a core microbiome. One of the primary challenges is the vast range of taxonomic resolution in seagrass studies that complicates meaningful comparisons.
The history of microbiome research in seagrasses has seen an expansion with the improvement of methods and technology. Research interests first sought to validate the existence of a seagrass holobiont by characterizing consistently present microbes on the plant that are distinct from the surroundingwater column andsediment.[135] As this characterization began,[136]high throughput sequencing, a data intensive and cost effective method to analyzeDNA andRNA, allowed for an increase of microbiome work in aquatic environments.[137]
The original interests shifted and radiated with studies characterizing seagrass communities by microenvironment (rhizosphere, endosphere, phyllosphere), life stage, and geographic region.[138] Conservation efforts[139] have begun considering microbial communities within rearing methods as they are linked to plant fitness and reproductive success.[140] Microbe-microbe interactions, seagrass microbe colonization and community shifts, disease and pathogenic interactions, and how environmental variables shift communities over time are examples of current fields within modern seagrass work.
Future directions aim to understand the functional mechanisms of seagrass associated microbes but are faced with challenges. Seagrass microbiomes and their interactions can bepolymicrobial;[141] which makes isolating and assigning functions difficult.Metagenomics still has lapses as low abundance organisms can be missed by the sequencing process and mechanistic pathways are not always determined with high confidence.[142] Identifying causative agents in seagrass diseases is a growing objective as populations are declining globally.[143]
Despite only covering 0.1 - 0.2% of the ocean’s surface, seagrasses form critically important ecosystems. Much like many other regions of the ocean, seagrasses have been faced with an accelerating global decline.[144] Since the late 19th century, over 20% of the global seagrass area has been lost, with seagrass bed loss occurring at a rate of 1.5% each year.[145] Of the 72 global seagrass species, approximately one quarter (15 species) could be considered at aThreatened orNear Threatened status on theIUCN’s Red List of Threatened Species.[146] Threats include a combination of natural factors, such as storms and disease, and anthropogenic in origin, includinghabitat destruction,pollution, andclimate change.[144]
By far the most common threat to seagrass is human activity.[147][148] Up to 67 species (93%) of seagrasses are affected by human activity along coastal regions.[146] Activities such as coastal land development, motorboating, and fishing practices liketrawling either physically destroy seagrass beds or increaseturbidity in the water, causing seagrass die-off. Since seagrasses have some of the highest light requirements ofangiosperm plant species, they are highly affected by environmental conditions that change water clarity and block light.[149]
Seagrasses are also negatively affected by changing global climatic conditions. Increased weather events,sea level rise, and higher temperatures as a result ofglobal warming all have the potential to induce widespread seagrass loss. An additional threat to seagrass beds is the introduction of non-native species. For seagrass beds worldwide, at least 28 non-native species have become established. Of theseinvasive species, the majority (64%) have been documented to infer negative effects on the ecosystem.[149]
Another major cause of seagrass disappearance iscoastal eutrophication. Rapidly developing human population density along coastlines has led to high nutrient loads in coastal waters from sewage and other impacts of development. Increased nutrient loads create an accelerating cascade of direct and indirect effects that lead to seagrass decline. While some exposure to high concentrations of nutrients, especiallynitrogen andphosphorus, can result in increased seagrass productivity, high nutrient levels can also stimulate the rapid overgrowth ofmacroalgae andepiphytes in shallow water, andphytoplankton in deeper water. In response to high nutrient levels, macroalgae form dense canopies on the surface of the water, limiting the light able to reach thebenthic seagrasses.[150]Algal blooms caused by eutrophication also lead tohypoxic conditions, which seagrasses are also highly susceptible to. Since coastal sediment is generallyanoxic, seagrass must supply oxygen to their below-ground roots either throughphotosynthesis or by the diffusion of oxygen in the water column. When the water surrounding seagrass becomes hypoxic, so too do seagrass tissues. Hypoxic conditions negatively affect seagrass growth and survival with seagrasses exposed to hypoxic conditions shown to have reduced rates of photosynthesis, increased respiration, and smaller growth. Hypoxic conditions can eventually lead to seagrass die-off which creates apositive feedback cycle, where the decomposition of organic matter further decreases the amount of oxygen present in the water column.[150]
Possible seagrass population trajectories have been studied in theMediterranean sea. These studies suggest that the presence of seagrass depends on physical factors such as temperature, salinity, depth and turbidity, along with natural phenomena like climate change and anthropogenic pressure. While there are exceptions, regression was a general trend in many areas of the Mediterranean Sea. There is an estimated 27.7% reduction along the southern coast ofLatium, 18%-38% reduction in the Northern Mediterranean basin, 19%-30% reduction onLigurian coasts since the 1960s and 23% reduction inFrance in the past 50 years. InSpain the main reason for regression was due to human activity such as illegaltrawling andaquaculture farming. It was found that areas with medium to high human impact suffered more severe reduction. Overall, it was suggested that 29% of known areal seagrass populations have disappeared since 1879. The reduction in these areas suggests that should warming in the Mediterranean basin continue, it may lead to a functional extinction ofPosidonia oceanica in the Mediterranean by 2050. Scientists suggested that the trends they identified appear to be part of a large-scale trend worldwide.[151]
seagrass in Sequim Bay, WA, visible via side-scan sonar in SonarView application, surveying with BlueBoat
Conservation efforts are imperative to the survival of seagrass species. While there are many challenges to overcome with respect to seagrass conservation there are some major ones that can be addressed. Societal awareness of what seagrasses are and their importance to human well-being is incredibly important. As the majority of people become more urbanized they are increasingly more disconnected from the natural world. This allows for misconceptions and a lack of understanding of seagrass ecology and its importance. Additionally, it is a challenge to obtain and maintain information on the status and condition of seagrass populations. With many populations across the globe, it is difficult to map the current populations. Another challenge faced in seagrass conservation is the ability to identify threatening activities on a local scale. Also, in an ever growing human population, there is a need to balance the needs of the people while also balancing the needs of the planet. Lastly, it is challenging to generate scientific research to support conservation of seagrass. Limited efforts and resources are dedicated to the study of seagrasses.[152] This is seen in areas such asIndia andChina where there is little to no plan in place to conserve seagrass populations. However, the conservation and restoration of seagrass may contribute to 16 of the 17UN Sustainable Development Goals.[153]
In a study of seagrass conservation in China, several suggestions were made by scientists on how to better conserve seagrass. They suggested that seagrass beds should be included in the Chinese conservation agenda as done in other countries. They called for the Chinese government to forbid land reclamation in areas near or in seagrass beds, to reduce the number and size of culture ponds, to control raft aquaculture and improve sediment quality, to establish seagrass reserves, to increase awareness of seagrass beds to fishermen and policy makers and to carry out seagrass restoration.[154] Similar suggestions were made in India where scientists suggested that public engagement was important. Also, scientists, the public, and government officials should work in tandem to integratetraditional ecological knowledge and socio-cultural practices to evolve conservation policies.[155]
World Seagrass Day is an annual event held on March 1 to raise awareness about seagrass and its important functions in the marine ecosystem.[156][157]
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