Marine plants

Writing team: Jason Hall-Spencer (coordinating author), Joel C. Creed, Erik van Doorn, José Souto Rosa Filho, Dorsaf Kerfahi, Emad Koochaknejad, Carmen Mifsud (co-lead member), Nahid Osman, Edwin Lanfranco, Wenhai Lu, Mario Luiz Gomes Soares, Mehdi Ghodrati Shojaei (lead member), Nata Tavonvunchai and Lu Yang.

Key points

• Marine plant species are spreading poleward due to climate heating, with mangroves encroaching into salt marshes.
• Restoration has established marine plants in small areas but not at a scale to match historical losses; preservation of existing marine plants provides many benefits.
• Rates of mangrove loss have slowed as policies to conserve and maintain existing mangroves are beginning to work. Some losses have been offset by low biodiversity reforestation projects.
• Sabkha plants, not covered in previous World Ocean Assessments, are overlooked but form important marine wetland ecosystems in arid and semi-arid regions.

1. Introduction

Vascular marine plants create biodiverse habitats providing goods and services that are essential for achieving the Sustainable Development Goals (sect. 4, subchaps. 5G-5I; see also table 1 below). There are 72 seagrass species, and their diversity is highest in the tropical Indo-Pacific. Some meadows have several seagrass species, but most are monospecific. Thalassodendron pachyrhizum is the deepest living marine plant and occurs down to 63 m depth Ref 48. Mangrove diversity and extent peaks in tropical Asia with 69 species (and 13 hybrids) that belong to 18 families that include trees, shrubs, palms and ferns Ref 39. Rhizophora mangle is the most common mangrove tree species worldwide. Salt marshes occur from the tropics to the Arctic, with over 500 known species, including grasses, shrubs and herbs Ref 1 Ref 24. Sabkhas are often used for salt extraction Ref 3 Ref 29, and their flora, e.g. Atriplex, Salicornia, Salsola and Suaeda Species, tolerate high salinity, freshwater scarcity and extreme temperatures, with adaptations that include succulence, salt secretion and osmoregulation Ref 25 Ref 11.

2. Environmental change since the second World Ocean Assessment

Changes in overall status

Seagrasses

Twenty-two species are in decline due to the impacts of fishing, poor water quality, mariculture and coastal urban and industrial development (United Nations Environment Programme (UNEP), 2020). Ten are Vulnerable, and Phyllospadix japonicus and Zostera geojeensis are Endangered (International Union for Conservation of Nature (IUCN), 2024). Some seagrass meadows suffer from overconsumption by herbivores such as sea urchins (subchap. 4F) or turtles in places where their numbers have grown locally thanks to conservation measures (subchap. 5G). Seagrasses can recover when pressures on coastal systems are reduced; Halodule wrightii and Zostera japonica are increasing Ref 68, although invasive species are a growing threat Ref 5. "Blue carbon" and the role of marine plants in the carbon cycle are explained in subsection 5B, chapter 1. The only seagrass blue carbon project is in the United States of America, where 3,151 ha of Zostera marina has been restored since the publication of the second World Ocean Assessment.

Mangroves

Although rates of loss have slowed since the publication of the second World Ocean Assessment, some species, such as Bruguiera hainesii, remain Critically Endangered Ref 9 Ref 35 Ref 39. A global campaign, launched in 2022 and supported by 50 Governments, is aimed at protecting 15 million ha of mangroves worldwide. Some recent losses have been offset by restoration projects (Leal and Spalding, 2024; see also subchap. 5H), which are mainly focused on the following mangrove species: Rhizophora mangle, R. mucronata, R. apiculata, Bruguiera gymnorhiza, B. cylindrica, Ceriops tagal, Avicennia germinans, A. marina and Laguncularia racemosa (Verra Registry;2 Plan Vivo;3 Climate Action Reserve;4 Clean Development Mechanism5). The biodiversity of these plantations is lower than in natural mangrove forests Ref 43.

Salt marshes

These habitats are declining worldwide (for estimates of the rate, see subchap. 5I), often due to land reclamation, conversion to agriculture, increased erosion, sea level rise, eutrophication (Niner and others, 2019; Roman and others, 2023; see also sect. 5, subchap. 5A) and invasive species (sect. 4, chap. 6). Salt marsh species are spreading poleward due to recent climate heating Ref 10 Ref 13 and planting and restoration work has been successful in some regions Ref 77 Ref 40.

3. Region-specific changes in biodiversity

Arctic Ocean

Zostera marina is the only seagrass reported in the Arctic. This region has approximately 17% of the global extent of salt marshes, with at least 113 species of vascular plants (12% of Arctic flora); information on recent changes in their status is lacking Ref 64 Ref 75 although the region is warming rapidly, which is expected to favour the northward spread of temperate marine plants but threaten those adapted to surviving seasonal freezing conditions.

North Atlantic Ocean, Baltic Sea, Black Sea, Mediterranean Sea and North Sea

Phragmites australis has invaded western North Atlantic salt marshes; it is expensive and difficult to remove, but can provide ecosystem benefits Ref 46. Extensive areas of the previously degraded seagrasses Zostera marina, Ruppia maritima (Chesapeake Bay) and Thalassia testudinum (Tampa Bay) have recovered in the United States of America thanks to reductions in nutrient pollution. Avicennia germinans and Rhizophora mangle mangroves are expanding northward in the western North Atlantic Ref 10 Ref 69.

Blue carbon projects in the eastern North Atlantic are using A. germinans, A. africana, Laguncularia racemosa and R. mangle. Sabkhas can provide habitat for a wide diversity of vascular plant taxa (from 29 families) including endemics, e.g. Echiochilon simonneaui and E. chazaliei Ref 60, and critically endangered species, e.g. Limonium mucronulatum, which is found only in Cyprus Ref 63.

Endemic Posidonia oceanica meadows are receding in the Mediterranean due to human impacts, although some meadows of this and Cymodocea nodosa are expanding due to implemented legislation and restoration (de los Santos and others, 2019; see also table 2) and the use of best practices in transplantation (Pergent-Martini and others, 2024). Halophila stipulacea has spread in the region and H. decipiens, first reported in the Mediterranean in 2018, is expected to spread Ref 27 raising calls for improved biosecurity to prevent the arrival of non-native species Ref 26.

South Atlantic Ocean and wider Caribbean

The main blue carbon species now being planted in this region are the mangroves Laguncularia racemosa, Rhizophora mangle, Conocarpus erectus, Avicennia germinans and Rhizophora harisonii. Several mangrove species are at elevated risk of extinction in the Caribbean Ref 35. Collection of and commercial trade in Rhizophora mangle is regulated in the Caribbean (see table 2). In Brazil, 80 to 90% of mangroves are in protected areas and the species are listed as of Least Concern Ref 35. The mangroves Avicennia germinans, A. schaueriana, Rhizophora mangle and Laguncularia racemosa are all expanding southward, causing the loss of salt marsh Spartina alterniflora, S. densiflora and Acrostichum plants Ref 13. The mangrove Sonneratia apetala has been introduced from the Indo-Pacific Ref 20. The seagrasses Halodule wrightii and Halophila decipiens have expanded south by approximately 250 km in the twenty-first century due to climate heating. The South Atlantic has vegetated hypersaline tidal flats (locally called "apicuns" or "salgados") that are easily damaged by human activities Ref 2. The West African coast has one of the highest rates of recent mangrove plant loss worldwide, due to agriculture, urbanization and cutting wood to burn (Food and Agriculture Organization of the United Nations (FAO), 2023) as well as oil pollution and the spread of invasive nipa palm. The Calabar Protocol on Sustainable Mangrove Management to the Convention for Cooperation in the Protection, Management and Development of the Marine and Coastal Environment of the Atlantic Coast of the West, Central and Southern Africa Region (see table 2), adopted in 2019, establishes rules for the environmental protection and conservation of mangroves as well as their use.

Indian Ocean, Arabian Sea, Bay of Bengal, Red Sea, Gulf of Aden and Persian Gulf

Since 2018, the main species planted in blue carbon projects in this region are Avicennia marina, Bruguiera gymnorhiza, Ceriops tagal, Rhizophora apiculata and R. mucronata. Sundarbans is the largest mangrove forest in the world (10,200 km²) and a world heritage site (see table 1). Here around 50% of the trees have been felled for timber and to create space for agriculture and shrimp farms. The forest is being rapidly altered due to sea level rise (Intergovernmental Panel on Climate Change (IPCC), 2022). Salt-tolerant species are increasing and spreading (e.g. Avicennia marina and Phoenix paludosa) with no plans in place to allow for the natural inland retreat of mangrove plants Ref 36. The Indian Ocean mangroves Bruguiera hainesii and Sonneratia griffithii are critically endangered Ref 55 Ref 35.

Around the Persian Gulf and the Sea of Oman, conservation and restoration has contributed to the expansion of mangrove plants Ref 50 Ref 19. In the Islamic Republic of Iran they are expanding with sea level rise where landward margins remain unimpeded by coastal development Ref 31. Mangrove extent is now increasing in the Red Sea and the Gulf of Aden Ref 7 with A. marina plantations in Saudi Arabia, Egypt and the Sudan. Restoration of A. marina, Bruguiera gymnorrhiza, Ceriops tagal and Rhizophora mucronata mangroves is underway in Somalia, Mozambique, Madagascar, the United Republic of Tanzania and Kenya.

Middle Eastern coastal sabkhas host 12 marine plant families that form biodiversity hotspots and carbon sinks Ref 28 Ref 15 Ref 18. Some are native to this region, such as Arthrocnemum macrostachyum and Halopeplis perfoliata. The few sabkha plants that have had their conservation status listed are categorized as of Least Concern Ref 35. Several types of sabkha plants are economically important (e.g. Aeluropus lagopoides, Juncus rigidus, Phoenix dactylifera, Suaeda vermiculata).

The first seagrass restoration initiative for this region was announced in 2024 to rescue and transplant eight Red Sea seagrass species. In the United Republic of Tanzania, best practices for the transplantation of Syringodium isoetifolium are being promoted Ref 72. In Mozambique and South Africa, experimental transplantation of the regionally endangered Zostera capensis was recently achieved Ref 4 Ref 51 Ref 71. In Kenya, there are attempts to restore the seagrasses Thalassodendron ciliatum, Thalassia hemprichii, Enhalus acoroides, and Syringodium isoetifolium. Under the framework of the Convention for the Protection, Management and Development of the Marine and Coastal Environment of the Eastern African Region (see table 2), detailed guidelines on seagrass and mangrove ecosystem restoration were published in 2020. Trial transplantations of Thalassodendron ciliatum and Thalassia hemprichii confirm that protecting existing meadows is more effective than planting new ones.

North Pacific Ocean

This region has around 250 to 300 salt marsh taxa, including species of Suaeda, Triglochin, and Salicornia; some, such as T. maritima, are vulnerable Ref 35. Over 200 salt marsh plant species grow along the western North Pacific Ref 70 where invasive Spartina alterniflora has colonized and altered 63% of the coastal marshes of China Ref 81 Ref 40. The use of S. alterniflora for coastal protection has threatened indigenous marine plants, birds, fisheries and tourism Ref 76 Ref 84 so it is now being removed; 68,000 ha had been removed in China by 2025, according to the Special Action Plan for Spartina Removal and Coastal Marsh Restoration (2022-2025) by the State Forestry and Grassland Administration of China. There has also been large-scale replantating of native species such as the mangrove Kandelia obovata, salt marsh plants such as Suaeda salsa, Scirpus mariqueter and the seagrass Zostera marina Ref 22 Ref 79. Invasive S. alterniflora is also spreading in Japan and the Republic of Korea, where large-scale eradication projects are ongoing Ref 37 Ref 49 Ref 38.

Climate heating has caused the recent northward expansion of the mangroves Conocarpus erectus in Mexico Ref 57 and Kandelia candel in Taiwan Province of China. Iriomote Island in Japan has 11 species of mangrove plants and nearly 70% of the national mangrove area Ref 32. Here, species include Kandelia obovata, Bruguiera gymnorrhiza, and Rhizophora stylosa, which are conserved well in a natural world heritage site (United Nations Educational, Scientific and Cultural Organization (UNESCO), 2021; see also table 1). Some mangrove species are at an elevated threat of extinction along the North Pacific coasts of Central America Ref 35. China, home to 37 mangrove species, is reversing habitat loss with the Government's Special Action Plan for Spartina Removal and Coastal Marsh Restoration (2022-2025) which is aimed at the planting of over 8,800 ha of new forest and restoring 8,200 ha of mangroves Ref 58. Restoration efforts also include rare and endangered species like Lumnitzera littorea, Sonneratia hainanensis and S. ovata (Zhang and others, 2024).

Zostera, Ruppia and Phyllospadix seagrasses are widely distributed in the North Pacific, where they are under pressure from some of the most densely populated areas in the world Ref 66 Ref 78. Species such as Zostera caespitosa, Phyllospadix iwatensis and Halophila beccarii are listed as vulnerable Ref 80 Ref 17 Ref 83 Ref 35. In the eastern North Pacific, eel grass decline has been exacerbated by marine heatwaves, sea star wasting disease, reduced water clarity and physical damage from human activities such as boating and coastal development Ref 12 Ref 53. Similarly, between 2015 and 2021, over 1,000 ha of Zostera japonica were lost in the Yellow River estuary in China due to Spartina alterniflora invasion and typhoons; restoration efforts are aimed at mitigating this damage Ref 83 Ref 40.

South Pacific Ocean

Improved water quality has resulted in recent regrowth of the seagrasses Posidonia australis and Posidonia sinuosa Ref 23. Avicennia marina, the only mangrove species in New Zealand, is expanding south throughout the South Pacific, encroaching upon salt marshes Ref 74. In Australia, subtropical and temperate coastal salt marsh plants are threatened Ref 35, but taxa are being conserved and recovered, such as Sarcocornia quinqueflora, Suaeda australis and Sporobolus virginicus Ref 6 Ref 61. Posidonia australis restoration has worked in small areas Ref 65, but not yet at a scale to match historical losses. Zostera chilensis is considered endangered in the South-East Pacific.

Note: there are no marine plants in the Southern Ocean.

4. Key remaining knowledge and capacity gaps

Much of what is known about changes in marine plants worldwide comes from remote sensing. A lack of in situ monitoring, due to a lack of marine botanists and funding, means that there are knowledge gaps regarding the status of marine plants in most regions, with sabkhas especially overlooked. Molecular techniques have been developed for marine plant identification, but the infrastructure and human resources to do this work is lacking in many regions. The resilience of most marine plants to changing climate and ocean conditions has not been assessed.

Increased protection of marine plants requires international attention, support and cooperation. Marine plants provide biodiversity and ecosystem function support and coastal protection and contribute to livelihoods and improved water quality Ref 44. In some areas, mangroves have been so damaged that these services have been lost and the habitats have become a source, rather than a sink, of greenhouse gasses Ref 8. Criticisms of carbon markets largely centre around the integrity and additional benefit of carbon credits and certification schemes Ref 30 Ref 73 Ref 14. Assessments of carbon stored by marine plants present difficulties in submersed ecosystems Ref 45 Ref 54. Many blue carbon projects depend on philanthropy, rather than carbon credit finance; the viability of carbon finance for marine plant conservation is a current knowledge gap.

Table 1 Global legal and policy instruments applicable to marine plants

Source: Prepared by the writing team.

Table 2 Regional legal instruments applicable to marine plants

Source: Prepared by the writing team.

References

1. Adam, Paul (2016). Saltmarshes. In Encyclopedia of Estuaries. Encyclopedia of Earth Sciences Series, Kennish, M.J., ed. Springer, Dordrecht.
2. Albuquerque, Antonia G.B.M., and others (2014). Hypersaline tidal flats (apicum ecosystems): the weak link in the tropical wetlands chain. Environmental Reviews, 22, 99-109.
3. Alshenawy, Abdulhafiz O., and others (2021). A review on the characteristics of sabkha soils in the Arabian Gulf Region. Arabian Journal of Geosciences, 14, 1-15.
4. Amone-Mabuto, Manuela, and others (2022). A field experiment exploring disturbance-and-recovery, and restoration methodology of Zostera capensis to support its role as a coastal protector. Nordic Journal of Botany, e03632.
5. Beca-Carretero, Pedro, and others (2024). Climate change and the presence of invasive species will threaten the persistence of the Mediterranean seagrass community. Science of The Total Environment, 910, 168675.
6. Beaumont, Kieren P., and Dittman, Sabine (2022). Early seed dynamics and tidal marsh revegetation of a salt pond following tidal reconnection. Applied Vegetation Science, 25, e12661.
7. Blanco-Sacristán, Javier, and others (2022). Mangrove distribution and afforestation potential in the Red Sea. Science of the Total Environment.
8. Bruederle, Anna, and Hodler, Roland (2019). Effect of oil spills on infant mortality in Nigeria. Proceedings of the National Academy of Sciences 116, 5467-5471.
9. Bunting, Pete, and others (2022). Global Mangrove Extent Change 1996-2020: Global Mangrove Watch Version 3.0. Remote Sensing, 14, 3657.
10. Cavanaugh, Kyle C., and others (2019). Climate-driven regime shifts in a mangrove-saltmarsh ecotone over the past 250 years. Proceedings of the National Academy of Sciences, 116: 21602-21608.
11. Chenchouni, Haroun (2017). Assessing the ecology of halophytes for developing salt-tolerant crops in arid and semiarid regions. In Plant Adaptation to Environmental Change: Significance of Amino Acids and their Derivatives (pp. 75-90). Springer.
12. Christiaen, Bart, and others (2022). Puget Sound Seagrass Monitoring Report, monitoring year 2018-2020. Nearshore Habitat Program. Washington State Department of Natural Resources, Olympia, WA.
13. Cohen, Marcelo C.L., and others (2020). Southward migration of the austral limit of mangroves in South America. CATENA, 195: 104775.
14. Comte, Adrien, and others (2023). Blue carbon credits: a lot of promises but even more uncertainties for the Global South. Policy Brief, COP28, UAE, 1-4.
15. Dar, Basharat A., and others (2022). Vegetation composition of the halophytic grass Aeluropus lagopoides communities within coastal and inland sabkhas of Saudi Arabia. Plants,, 11, 666.
16. De Los Santos, Carmen B., and others (2019). Recent trend reversal for declining European seagrass meadows. Nature Communications, 10(1), 3356.
17. Du, Jianguo, and others (2023). Protect seagrass meadows in China's waters. Science, 379(6631), 447-447.
18. Eid, Ebrahem M., and others (2023). Modeling soil organic carbon at coastal sabkhas with different vegetation covers at the Red Sea coast of Saudi Arabia. Journal of Marine Science and Engineering, 11, 295.
19. Erfanifard, Yousef, and others (2022). Assessment of Iran's Mangrove Forest Dynamics (1990-2020) Using Landsat Time Series. Remote Sensing, 14(19), article 19.
20. Eysink, Geraldo, and others (2023). First Occurrence in Mangroves of South America of the Exotic Species Sonneratia apetala Buch.- Ham. From The Indo-Malayan Region. Biota Neotropica, 23, 4, 1-5.
21. FAO (2023). The world's mangroves 2000-2020. Rome. https://doi.org/10.4060/cc7044en. 
22. Feng, JianXiang, and others (2017). Ecological restoration by native-invasive species replacement for mangrove wetlands in Zhangjiang River Estuary, Fujian. Oceanologia et Limnologia Sinica, 48(2), 266-275.
23. Fernandes, Milena B., and others (2022). Landsat historical records reveal large-scale dynamics and enduring recovery of seagrasses in an impacted seascape. Science of The Total Environment, 813,152646.
24. Fitzgerald, Duncan M., and Hughes, Zoe J. (2021). Salt Marshes: Function, Dynamics, and Stresses. Cambridge University Press.
25. Flowers, Timothy J., and Colmer, Timothy D. (2008). Salinity tolerance in halophytes. New Phytologist, 179(4), 945-963.
26. Galil, Bella, and others (2017). The enlargement of the Suez Canal - Erythraean introductions and management challenges. Management of Biological Invasions, 8, 141-152.
27. Gerakaris, Vasilis, and others (2020). First record of the tropical seagrass species Halophila decipiens Ostenfeld in the Mediterranean Sea. Aquatic Botany, 160, 103151.
28. Ghazanfar, Shahina A., and others (2019). Plants of Sabkha Ecosystems of the Arabian Peninsula. In Sabkha Ecosystems, Tasks for Vegetation Science V I, B. Gul and others, eds., 2019.
29. Ghazanfar, Shahina A. (2024). Biogeography and Conservation in the Arabian Peninsula: A Present Perspective. Plants, 13, 2091.
30. Guizar-Coutiño, Jones, and others (2022). A global evaluation of the effectiveness of voluntary REDD+ projects at reducing deforestation and degradation in the moist tropics. Conservation Biology, 36, e13970.
31. Hamzeh, M.A., and Lahijani, H.A.K. (2022). Soil and Vegetative Carbon Sequestration in Khuran Estuary Mangroves, Strait of Hormoz, During the Last 18 Centuries. Estuaries and Coasts, 45, 1583-1595.
32. Inoue, Tomomi, and others (2022). Mangroves of Japan. In Mangroves: Biodiversity, Livelihoods and Conservation, (pp. 463-487). Singapore: Springer Nature Singapore.
33. IPCC (2022). Climate Change: Impacts, Adaptation, and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, H .- O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama, eds. Cambridge University Press.
34. Irani, Maryam, and others. A framework for coastal flood hazard assessment under sea level rise: Application to the Persian Gulf. Journal of Environmental Management, 349, 119502.Hogarth, PJ. 2015. The Biology of Mangroves and Seagrasses, 3rd ed. Oxford, Oxford University Press, 2024.
35. IUCN (2024). The IUCN Red List of Threatened Species. Version 202401. https://www.iucnredlist.org. 
36. Khan, Md F.A., and others (2020). Mangrove forest policy and management: Prevailing policy issues, actors' public claims and informal interests in the Sundarbans of Bangladesh. Ocean & coastal management, 186, 105090.
37. Kim, Sungtae, and others (2023). Vertical distribution of the salt marsh invader Spartina alterniflora and native halophytes on the west coast of Korea in relation to tidal regimes. Aquatic Invasions, 18(3), 331-349.
38. Koyama, Akihiko, and others (2024). Sub-habitat classification of temperate salt marshes in Japan based on aquatic fauna. Global Ecology and Conservation, e03211.
39. Leal, M., and Spalding, M.D. (2024). The State of the World's Mangroves 2024. Global Mangrove Alliance.
40. Liu, Ningning, and Ma, Zhijun (2024). Ecological restoration of coastal wetlands in China: Current status and suggestions. Biological Conservation, 291, 110513.
41. Liu, Zezheng, and others (2024). A global meta-analysis on the drivers of salt marsh planting success and implications for ecosystem services. Nature Communications, 15(1), 3643.
42. Long, Kexin, and others (2024). Spatiotemporal disturbances and attribution analysis of mangrove in southern China from 1986 to 2020 based on time-series Landsat imagery. Science of The Total Environment, 912, 169157.
43. Lovelock, Catherine E., and others (2024). Mangrove ecology guiding the use of mangroves as nature-based solutions. Journal of Ecology.
44. Macreadie, Peter I., and others (2019). The future of Blue Carbon science. Nature Communications, 10(1), 3998.
45. Macreadie, Peter I., and others (2022). Operationalizing marketable blue carbon. One Earth. 5, 485-492.
46. Macy, Aaron, and others (2021). Changes in Ecosystem Nitrogen and Carbon Allocation with Black Mangrove (Avicennia germinans) Encroachment into Spartina alterniflora Salt Marsh. Ecosystems, 24, 1007-1023.
47. Maebara, Yu, and others. Genetic diversity of invasive Spartina alterniflora Loisel. (Poaceae) introduced unintentionally into Japan and its invasion pathway. Frontiers in Plant Science, 11, 556039, 2020.
48. Martin, Belinda C., and others (2023). Deep Meadows: Deep-Water Seagrass Habitats Revealed. Ecology, 104(10): e4150.
49. Matsuda, Ryuya, and others (2023). Effects of salinity, temperature, and immersion conditions on seed germination of invasive Spartina alterniflora Loisel (smooth cordgrass) in Japan. Regional Studies in Marine Science, 57, 102738.
50. Milani, Alireza S. (2018). Mangrove Forests of the Persian Gulf and the Gulf of Oman. In Threats to Mangrove Forests (vol. 25, pp. 53-75), C. Makowski and C. W. Finkl, eds. Springer International Publishing.
51. Mokumo, Mosihla F., and Adams, J.B. (2023). Investigating transplantation as a mechanism for seagrass restoration in South Africa. Restoration Ecology, 31(7), e13941.
52. Murray, Nicholas J., and others (2019). The global distribution and trajectory of tidal flats. Nature, 565(7738), 222-225.
53. Nahirnick, Natasha K. and others (2020). Long-Term Eelgrass Habitat Change and Associated Human Impacts on the West Coast of Canada. Journal of Coastal Research, 36 (1), 30-40.
54. Niner, Holly J., and Randalls, Samuel (2021). Good enough for governance? Audit and marine biodiversity offsetting in Australia. Geoforum, 120, 38-45.
55. Nuevo-Diego, Christine E., and others (2021). Pollinators necessary for the reproductive success of critically endangered mangrove, Sonneratia griffithii. Aquatic Botany, 169, 103340.
56. Obuah, Emmanuel E., and Keke, R.C. (2022). Mitigating the negative externalities of oil drilling activities in the Niger Delta, Nigeria. Open Access Library Journal, 9(5), 1-21.
57. Ochoa-Gómez, Jonathan G., and others (2021). Distribution and structure of Conocarpus erectus L. (Combretaceae) in the northern limit of the Pacific Ocean (Gulf of California). Ocean & Coastal Management 209, 105645.
58. Ouyang, Xiaoguang, and others (2024). Mangrove restoration in China's tidal ecosystems. Science, 385(6711), 836-836.
59. Pergent-Martini Christine, and others (2024). Guidelines for Posidonia oceanica restoration. Report Cooperation agreement Mediterranean Posidonia Network (MPN), French Biodiversity Agency (OFB) & University of Corsica Pasquale Paoli (UCPP) NºOFB-22-1310, 29 pp.
60. Qninba, Abdeljebbar, and others (2020). Sabkhat Imlili (Région Dakhla-Oued Eddahab), une zone humide saharienne relique, 152 pp.
61. Rankin, Caleb, and others (2023). Innovative tidal control successfully promotes saltmarsh restoration. Restoration Ecology, 31: e13774.
62. Roman, Charles T., and others (2023). Twenty Year Record of Salt Marsh Elevation Dynamics in Response to Sea Level Rise and Storm Driven Barrier Island Geomorphic Processes: Fire Island, NY, USA. Estuaries and Coasts, SI Wetland elevation dynamics.
63. Senni, Rachida, and De Belair, Gerard, A.H. (2020). Biodiversity of halophytes in semi-arid regions: case of Zharez Gharbi and Zahrez Chergui (Zaafrane-Djelfa) in Algeria. Ponte International Journal of Science and Research, 76(11).
64. Sergienko, Liudmila (2013). Salt marsh flora and vegetation of the Russian Arctic coasts. Czech Polar Reports 3, 30-37.
65. Sinclair, Elizabeth A., and others (2021). Advances in approaches to seagrass restoration in Australia. Ecological Management & Restoration, 22(1), 10-21.
66. Su, Zhinan, and others (2020). Changes in carbon storage and macrobenthic communities in a mangrove- seagrass ecosystem after the invasion of smooth cordgrass in southern China. Marine Pollution Bulletin, 152, 110887.
67. UNESCO World Heritage Centre (2021). Four natural and three cultural sites added to UNESCO's World Heritage List. Retrieved from https://whc.unesco.org/en/news/2318/. 
68. United Nations Environment Programme (2020). Out of the blue: The value of seagrasses to the environment and to people. Nairobi, 96 p.
69. Vervaeke, William, and others (2024). Ongoing range shift of mangrove foundation species: Avicennia germinans and Rhizophora mangle in Georgia, USA. 10.21203/rs.3.rs-4601188/v1.
70. Wang, Wen Qing, and Chen, Qiong (2013). Salt-tolerant plant resources from coastal areas of South China. Xiamen University Press, pp. 444.
71. Watson, Katie M., and others (2023). Using transplantation to restore seagrass meadows in a protected South African lagoon. PeerJ, 11.
72. Wegoro, January, and others (2022). Seagrass restoration in a high-energy environment in the Western Indian Ocean. Estuarine, Coastal and Shelf Science, 278, 108119.
73. West, Thales A.P., and others (2020). Overstated carbon ER from voluntary REDD+ projects in the Brazilian Amazon. PNAS. 117, 24188-24194.
74. Whitt, Ashley, and others (2020). March of the mangroves: Drivers of encroachment into southern temperate saltmarsh. Estuarine, Coastal and Shelf Science, 240, 106776.
75. Worthington, Thomas A., and others (2024). The distribution of global tidal marshes from Earth observation data. Global Ecology and Biogeography, 33, e13852.
76. Xia, Shaopan, and others (2021). Spartina alterniflora invasion controls organic carbon stocks in coastal marsh and mangrove soils across tropics and subtropics. Global Change Biology, 27(8), 1627-1644.
77. Xiao, Rong, and others (2020). Stronger network connectivity with lower diversity of soil fungal community was presented in coastal marshes after sixteen years of freshwater restoration. Science of the Total Environment, 744, 140623.
78. Xu, Shaoshun, and others (2021). Diversity, distribution and conservation of seagrass in coastal waters of the Liaodong Peninsula, North Yellow Sea, northern China: Implications for seagrass conservation. Marine Pollution Bulletin, 167, 112261.
79. Yang, Le, and others (2024). Effects of the comprehensive elimination of Spartina alterniflora along China's coast on blue carbon and scenario prediction after ecological restoration. Journal of Environmental Management, 369, 122283.
80. Yoshida, Goro, and others (2019). Carbon sequestration by seagrass and macroalgae in Japan: estimates and future needs. Blue carbon in shallow coastal ecosystems: carbon dynamics, policy, and implementation, 101-127.
81. Zhang, Xi, and others (2023). Continual expansion of Spartina alterniflora in China's temperate and subtropical coastal zones from 1985 to 2020. International Journal of Applied Earth Observation and Geoinformation, 117, 103192.
82. Zhang Y., and others (2021). Research on endangered mangrove species and recovery status in China. Journal of Applied Oceanography, 40(1), 142-153.
83. Zhou, Yi, and others (2023). Distribution status, degradation reasons and protection countermeasures of seagrass resources in China. Oceanologia et Limnologia Sinica, 54, 1248-1257.
84. Zhu, Xudong, and others (2024). Impacts of intensive smooth cordgrass removal on net ecosystem exchange in a saltmarsh-mangrove ecotone of Southeast China. Science of The Total Environment, 934, 173202.