Wikipedia

Gelidium

Gelidium is a genus of thalloid red algae comprising 134 species. Its members are known by a number of common names.[note 1]

Gelidium
Gelidium amansii
Gelidium amansii
Scientific classification Edit this classification
Clade: Archaeplastida
Division: Rhodophyta
Class: Florideophyceae
Order: Gelidiales
Family: Gelidiaceae
Genus: Gelidium
J.V. Lamouroux, 1813
Synonyms

Acanthopeltis Okamura, 1892

Description and life cycle

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Specimens can reach around 2–40 cm (0.79–16 in) in size. Branching is irregular, or occurs in rows on either side of the main stem. Gelidium produces tetraspores. Many of the algae in this genus are used to make agar.[1] Agarocolloids are known to be extracted in algae belonging to the orders Gracilariales and Gelidiales with certain applications in the food and cosmetics. Gelling properties often differ among species, seasons, seaweed age, and substitutions between sulphate esters, among other compounds. Sulphate composition often dictates gel strength, while methyl esters determine gelling and elasticity.[2]

Gelidium is assumed to follow the Polysiphonia life cycle, with sexual and tetrasporangial generations.[3] Tetrasporangia formation is also known to be affected by temperature and other environmental factors including light, salinity and moisture,[4] although germination rates remain unaffected based on an earlier study.[5]

In 1993, Gelidium robustum in Santa Barbara, California was investigated for 16-months showing tetrasporangial abundance throughout the year, but may not have the ability to germinate despite maximum spore output.[3]

Distribution

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Gelidium are widely distributed globally, specifically in tropical to temperate regions, but lacking in polar regions.[6] In the ocean, Gelidium can be found inhabiting the intertidal to subtidal zone.[7] Species from the genus require further studies to distinguish boundaries among members, as recent molecular research have shown that there are cryptic, unidentified species assumed to be regionally endemic and isolated but may also be ubiquitous in nature.[7] Some species are common in the Atlantic and Pacific Ocean (G. crinale) while some are confined in North Atlantic waters (G. pussillum)[8][9][10]. Reports of G. pussillum occurrence outside of its specified range may be questionable and requires further verification.[7]

Ecology

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Gelidiales consists of many species that are economically important as they produce agar while some serve ecologically significant functions such as substrate cover.[6] The growth of Gelidium can primarily be affected by nutrient availability and light. In turn, these factors are also regulated by temperature and water movement, respectively. Santelices (1991) evaluated how eight factors may affect Gelidium productivity, all of which are important in understanding how different interactions correlate to production yield. Some of these factors include seasonality, phenotypic characters, age, reproductive state, and even the source of the algae.[6]

Cultivation and exploitation

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An important agarophyte, Gelidium has been cultured in Korea[11] and China[12] since the early 1990s, with some cultivation efforts noted in Europe, specifically in Spain[13] and Portugal.[11][14] In South Africa, G. pristoides has been cultivated in the field while laboratory trials on G. crinale and Pterocladiella capillacea were tested in Israel.[15][16] In Portugal, G. sesquipedale has commonly been harvested for agar since the 1960s.[17] Management strategies are yet to be implemented especially among big commercial companies that should be responsible in harvesting the resource, similar to South Africa where the decrease in annual Gelidium landings show how fisher folk shifted to collecting kelp for abalone feeds instead of Gelidium harvesting.[18]

Gelidium has been found to be over-exploited in Japan, depleting algal beds[19] which in part, affects agar production, pushing the need for even more efforts in cultivation, replacing the practice of harvesting wild Gelidium.[20] In 2017, global data have shown that Norway, China, and Chile are among the countries that lead the overharvesting of seaweeds, mostly kelp.[20] Advances in Gelidium cultivation have been put forth including the use of floaters at sea and marine ponds for free-float technology in cultivation.[21] At its core, environmental factors are needed to be controlled for favorable growth of Gelidium revealing how ponds may be the better option among the set-ups.[20]

Agar is primarily extracted from Gelidium especially among North African Atlantic and South European species based on specific gel properties with water. In Morocco, Gelidium sesquipidale is known to be harvested during summer time to extract agar used commercially, making the country among the top producers in the world.[2]

Historical environmental analysis

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Gelidium species have been collected, pressed and maintained in herbaria and personal collections from the 1850s onwards since seaweed collecting became a popular pastime for the middle classes as well as scientists in Europe and North America.[22] These numerous well-documented specimens can provide information beyond taxonomy.[23]

Sensitive measurement of stable nitrogen isotope ratios in Gelidium species collected in southern Monterey Bay between 1878 and 2018 showed a pattern of changes that matched with changes in the California current and provided support for a theory about the end of the local fishing industry.[24] Nitrogen isotope ratios are well established as a measure of nutrient productivity in aquatic ecosystems. The California current runs along coastal California and correlation with information on fish catches indicates that an increase in nutrient-rich cold water is important for fish productivity, notably sardines.[25] The California current has only been measured since 1946. The correlations with the Gelidium nitrogen ratios allowed the California current to be projected back into the nineteenth century and compared with historical records of fish catches.[24] The data matched, notably for the highest sardine catches through the 1930s and then the sudden decrease from 1945 to 1950 that ended the Monterey cannery industry. This information supports the theory that environmental changes as well as overfishing caused the collapse of the local fishery business. More broadly, this suggests that elemental analysis of historical samples of macroalgae can provide evidence of primary productivity processes. The species used included specimens of G. coulteri, G. robustum, G. purpurascens, G. pusillum and G. arborescens collected over a 140-year timespan from the 6 km coastline between Point Pinos, Pacific Grove and Cannery Row, Monterey in California, US.[24]

Taxonomy and nomenclature

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Gelidiaceae has 159 species, considered to be the largest family in Gelidiales with four major genera: Capreolia, Gelidium, Gelidiophycus, and Ptilophora.[26]

Gelidium was first described by Lamouroux in 1813 and is regarded to be one the genera with the most species. Species diversity has been established by previous studies, whereas, molecular analysis reveals biogeographic relations that concerns its current distribution pattern in oceans.[7]

Identification of species has been a challenge as sexual plants are somewhat difficult to find in nature, therefore, other physiological features are examined instead, such as branching patterns and vegetative traits, but subsequent studies revealed that these are also affected by its development and environmental factors[9] highlighting the need for genetic studies utilizing genetic markers.[7]

Species

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Notes

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  1. ^ Recorded common names are tengusa, makusa, genso, niu mau tsai, japansche scheleiachtige mos, steen-or klipbloem, hay tsay, olus marinus, sajur laut, tschintschau, tschoo-hoae, onikusa, hirakusa, obusa, rødalge-slaegt, gelídeos, punalevä-suku, tokoroten, kanten, tokoro-tengusa, kinukusa, isingglass, hai-ten-gusa, tocoroten, tengusa-agar, limu lo-loa, hai-tengusa, onigusa, oyakusa, kanten weed, goumaocai, hime tengusa, shihua and tanmae.

References

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  • Guiry, M.D.; Guiry, G.M. (2008). "Gelidium". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved 2009-04-18.
  1. ^ Tronchin, E. M.; Freshwater, D. W.; Bolton, J. J.; Anderson, R. J. (2002). "A Reassessment and Reclassification of Species in the Genera Onikusa Akatsuka and Suhria J. Agardh ex Endlicher (Gelidiales, Rhodophyta) Based on Molecular and Morphological Data". Botanica Marina. 45 (6): 548–558. doi:10.1515/BOT.2002.058. S2CID 84425094.
  2. ^ a b Mouradi-Givernaud, Aziza; Amina Hassani, Lalla; Givernaud, Thierry; Lemoine, Yves; Benharbet, Oumaima (1999-04-01). "Biology and agar composition of Gelidium sesquipedale harvested along the Atlantic coast of Morocco". Hydrobiologia. 398: 391–395. doi:10.1023/A:1017094231494. ISSN 1573-5117. S2CID 23800143.
  3. ^ a b Melo, Ricardo A.; Neushul, Michael (1993). Chapman, A. R. O.; Brown, M. T.; Lahaye, M. (eds.). "Life history and reproductive potential of the agarophyte Gelidium robustum in California". Fourteenth International Seaweed Symposium. Developments in Hydrobiology. Dordrecht: Springer Netherlands: 223–229. doi:10.1007/978-94-011-1998-6_27. ISBN 978-94-011-1998-6.
  4. ^ Santelices, Bernabe; G, Bernabé Santelices (1988). Synopsis of Biological Data on the Seaweed Genera Gelidium and Pterocladia (Rhodophyta). Food & Agriculture Org. ISBN 978-92-5-102717-2.
  5. ^ Correa, J.; Avila, M.; Santelices, B. (1985-03-01). "Effects of some environmental factors on growth of sporelings in two species of Gelidium (Rhodophyta)". Aquaculture. 44 (3): 221–227. doi:10.1016/0044-8486(85)90246-7. ISSN 0044-8486.
  6. ^ a b c Santelices, B. (1991). Juanes, J. A.; Santelices, B.; McLachlan, J. L. (eds.). "Production ecology of Gelidium". International Workshop on Gelidium. Developments in Hydrobiology. Dordrecht: Springer Netherlands: 31–44. doi:10.1007/978-94-011-3610-5_3. ISBN 978-94-011-3610-5.
  7. ^ a b c d e Boo, Ga Hun; Kim, Kyeong Mi; Nelson, Wendy A.; Riosmena-Rodríguez, Rafael; Yoon, Kyung Ju; Boo, Sung Min (April 2014). "Taxonomy and distribution of selected species of the agarophyte genus Gelidium (Gelidiales, Rhodophyta)". Journal of Applied Phycology. 26 (2): 1243–1251. doi:10.1007/s10811-013-0111-7. ISSN 0921-8971. S2CID 14936519.
  8. ^ Kim, Kyeong-Mi; Boo, Sung-Min (2012). "Phylogenetic relationships and distribution of Gelidium crinale and G. pusillum (Gelidiales, Rhodophyta) using cox1 and rbcL sequences". Algae. 27 (2): 83–94. doi:10.4490/algae.2012.27.2.083. ISSN 1226-2617. S2CID 83652614.
  9. ^ a b Freshwater, D. Wilson; Rueness, J. (1994-05-01). "Phylogenetic relationships of some European Gelidium (Gelidiales, Rhodophyta) species, based on rbcL nucleotide sequence analysis". Phycologia. 33 (3): 187–194. doi:10.2216/i0031-8884-33-3-187.1. ISSN 0031-8884.
  10. ^ Millar, Alan J. K.; Freshwater, D. Wilson (2005-06-30). "Morphology and molecular phylogeny of the marine algal order Gelidiales (Rhodophyta) from New South Wales, including Lord Howe and Norfolk Islands". Australian Systematic Botany. 18 (3): 215–263. doi:10.1071/SB04041. ISSN 1446-5701.
  11. ^ a b Melo, Ricardo A. (1998-06-01). "Gelidium commercial exploitation: natural resources and cultivation". Journal of Applied Phycology. 10 (3): 303–314. doi:10.1023/A:1008070419158. ISSN 1573-5176. S2CID 32635073.
  12. ^ Fei, X. G.; Huang, L. J. (1991). Juanes, J. A.; Santelices, B.; McLachlan, J. L. (eds.). "Artificial sporeling and field cultivation of Gelidium in China". International Workshop on Gelidium. Developments in Hydrobiology. Dordrecht: Springer Netherlands: 119–124. doi:10.1007/978-94-011-3610-5_11. ISBN 978-94-011-3610-5.
  13. ^ Camba, Juan Antonio Seoane (1997). ""Gelidium sesquipedale" (clem) thuret cultivation in Galicia (Spain)". Lagascalia. 19 (1): 179–186. ISSN 0210-7708.
  14. ^ Salinas, J. M. (1991). Juanes, J. A.; Santelices, B.; McLachlan, J. L. (eds.). "Spray system for re-attachment of Gelidium sesquipedale (Clem.) Born. et Thur. (Gelidiales: Rhodophyta)". International Workshop on Gelidium. Developments in Hydrobiology. Dordrecht: Springer Netherlands: 107–117. doi:10.1007/978-94-011-3610-5_10. ISBN 978-94-011-3610-5.
  15. ^ Boulus, Areen; Spaneir, Ehud; Friedlander, Michael (2007-03-03). "Effect of outdoor conditions on growth rate and chemical composition of Gelidium crinale in culture". Journal of Applied Phycology. 19 (5): 471. doi:10.1007/s10811-007-9158-7. ISSN 1573-5176. S2CID 43030778.
  16. ^ Gal-Or, Sharon; Israel, Alvaro (2004-06-01). "Growth responses ofPterocladiella capillacea(Rhodophyta) in laboratory and outdoor cultivation". Journal of Applied Phycology. 16 (3): 195–202. doi:10.1023/B:JAPH.0000048505.13667.bf. ISSN 1573-5176. S2CID 38064200.
  17. ^ Santos, Rui; Duarte, Pedro (1991-03-01). "Marine plant harvest in Portugal". Journal of Applied Phycology. 3 (1): 11. doi:10.1007/BF00003915. ISSN 1573-5176. S2CID 1682347.
  18. ^ Troell, M.; Robertson-Andersson, D.; Anderson, R. J.; Bolton, J. J.; Maneveldt, G.; Halling, C.; Probyn, T. (2006-06-30). "Abalone farming in South Africa: An overview with perspectives on kelp resources, abalone feed, potential for on-farm seaweed production and socio-economic importance". Aquaculture. 257 (1): 266–281. doi:10.1016/j.aquaculture.2006.02.066. hdl:10566/1005. ISSN 0044-8486.
  19. ^ Fujita, D.; Ishikawa, T.; Kodama, S.; Kato, Y.; Notoya, M. (2006-10-01). "Distribution and Recent Reduction of Gelidium Beds in Toyama Bay, Japan". Journal of Applied Phycology. 18 (3): 591–598. doi:10.1007/s10811-006-9060-8. ISSN 1573-5176. S2CID 9864922.
  20. ^ a b c Buschmann, Alejandro H.; Camus, Carolina; Infante, Javier; Neori, Amir; Israel, Álvaro; Hernández-González, María C.; Pereda, Sandra V.; Gomez-Pinchetti, Juan Luis; Golberg, Alexander; Tadmor-Shalev, Niva; Critchley, Alan T. (2017-10-02). "Seaweed production: overview of the global state of exploitation, farming and emerging research activity". European Journal of Phycology. 52 (4): 391–406. doi:10.1080/09670262.2017.1365175. ISSN 0967-0262. S2CID 53640917.
  21. ^ Friedlander, Michael (2009), Borowitzka, Michael A.; Critchley, Alan T.; Kraan, Stefan; Peters, Akira (eds.), "Advances in cultivation of Gelidiales", Nineteenth International Seaweed Symposium: Proceedings of the 19th International Seaweed Symposium, held in Kobe, Japan, 26–31 March 2007., Developments in Applied Phycology, vol. 2, Dordrecht: Springer Netherlands, pp. 1–6, doi:10.1007/978-1-4020-9619-8_1, ISBN 978-1-4020-9619-8, retrieved 2022-01-24
  22. ^ Giaimo, Cara. "The Forgotten Victorian Craze for Collecting Seaweed". Atlas Obscura. Retrieved 27 October 2020.
  23. ^ Trethewey, Laura. "What Victorian-era seaweed pressings reveal about our changing seas". The Guardian. Retrieved 27 October 2020.
  24. ^ a b c Miller, Emily A; Lisin, Susan E; Smith, Celia M; Van Houtan, Kyle S (2020). "Herbaria macroalgae as a proxy for historical upwelling trends in Central California". Proceedings of the Royal Society B. 287 (1929): 20200732. doi:10.1098/rspb.2020.0732. PMC 7329038. PMID 32546101.
  25. ^ Ware, D M; Thompson, R E (1991). "Link between longterm variability in upwelling and fish production in the northeast Pacific Ocean". Can. J. Fish. Aquat. Sci. 48 (12): 2296–2306. doi:10.1139/f91-270. Retrieved 27 October 2020.
  26. ^ JAMAS, MAYRA; IHA, CINTIA; C. OLIVEIRA, MARIANA; M. P. B. GUIMARÃES, SILVIA; T. FUJII, MUTUE (2017-07-25). "Morphological and molecular studies on Gelidiaceae and Gelidiellaceae (Gelidiales, Rhodophyta) from Brazil with description of the new species Gelidium calidum". Phytotaxa. 314 (2): 195. doi:10.11646/phytotaxa.314.2.2. ISSN 1179-3163.
  • Toefy, R., Gibbons, M.J. & McMillan, I.K. 2005. The foraminifera associated with the alga Gelidium pristoides, South Africa. African Invertebrates 46: 1-26.[1]
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