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[[File:CAS Macrocystis 2.JPG|thumb|{{largethumb}}|Giant kelp]]
[[File:CAS Macrocystis 2.JPG|thumb|{{largethumb}}|Giant kelp]]


Aquaculture of [[giant kelp]], ''Macrocystis pyrifera'', is the cultivation of kelp for uses such as food, [[Dietary supplement|dietary supplements]] or potash.<ref name = "Abbott">Abbott 1996</ref>{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}} Giant kelp contains compounds such as [[iodine]], [[potassium]], other minerals vitamins and [[carbohydrates]].<ref name = "Bushing 2000">Bushing 2000</ref><ref name="Connor 1989">Connor 1989, p. 58</ref>
Aquaculture of [[giant kelp]], ''Macrocystis pyrifera'', is the cultivation of kelp for uses such as food, [[Dietary supplement|dietary supplements]] or potash.{{sfn|Abbott|1996}}{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}} Giant kelp contains compounds such as [[iodine]], [[potassium]], other minerals vitamins and [[carbohydrates]].<ref name = "Bushing 2000">Bushing 2000</ref><ref name="Connor 1989">Connor 1989, p. 58</ref>


== History ==
== History ==
At the beginning of the 20th century California kelp beds were harvested for their [[potash]].<ref name="Abbott" />{{sfn|Neushul|1987}}{{sfn|Druehl|Baird|Lindwall|1988}} Commercial interest increased during the 1970s and the 1980s due to the production of [[alginate]]s, and also for biomass production for animal feed due to the [[1970s energy crisis|energy crisis]].{{sfn|Neushul|1987}}{{sfn|Druehl|Baird|Lindwall|1988}}{{sfn
At the beginning of the 20th century California kelp beds were harvested for their [[potash]].{{sfn|Abbott|1996}}{{sfn|Neushul|1987}}{{sfn|Druehl|Baird|Lindwall|1988}} Commercial interest increased during the 1970s and the 1980s due to the production of [[alginate]]s, and also for biomass production for animal feed due to the [[1970s energy crisis|energy crisis]].{{sfn|Neushul|1987}}{{sfn|Druehl|Baird|Lindwall|1988}}{{sfn
Gerard|1987}} However commercial production for ''M. pyrifera'' never became a reality. With the end of the energy crisis and the decline in [[alginate]] prices, research into farming ''Macrocystis'' declined.{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}
Gerard|1987}} However commercial production for ''M. pyrifera'' never became a reality. With the end of the energy crisis and the decline in [[alginate]] prices, research into farming ''Macrocystis'' declined.{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}


The supply of ''M. pyrifera'' for alginate production relied heavily on restoration and management of natural beds during the early 1990s.{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}<ref name="Buschmann ''et al.'' 2006" /> Other functions such as substrate stabilization were explored in California, where the “Kelp bed project” transplanted 3-6m adult specimens to increase the stability of the harbor and promote diversity.<ref name="Buschmann ''et al.'' 2006" /><ref name="Simenstad ''et al.''1978">Simenstad ''et al.''1978</ref>
The supply of ''M. pyrifera'' for alginate production relied heavily on restoration and management of natural beds during the early 1990s.{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}{{sfn|Buschmann||Varela||Hernández-González|2008}} Other functions such as substrate stabilization were explored in California, where the “Kelp bed project” transplanted 3-6m adult specimens to increase the stability of the harbor and promote diversity.{{sfn|Buschmann||Varela||Hernández-González|2008}}<ref name="Simenstad ''et al.''1978">Simenstad ''et al.''1978</ref>


===Twenty-first century===
===Twenty-first century===
The demand for ''M. pyrifera'' increased due to newfound uses such as [[fertilizer]]s, [[bioremediation]], and as feed for [[abalone]] and [[sea urchin|sea urchins]].{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}<ref name="Buschmann ''et al.'' 2006">Buschmann ''et al.'' 2006</ref> Research is investigating its use as feed for other [[aquaculture]] species such as shrimp.<ref name="Buschmann ''et al.'' 2006" /><ref name="Cruz ''et al.'' 2009">Cruz ''et al.'' 2009</ref>
The demand for ''M. pyrifera'' increased due to newfound uses such as [[fertilizer]]s, [[bioremediation]], and as feed for [[abalone]] and [[sea urchin|sea urchins]].{{sfn|Gutierrez|Correa|Tomás|Muñoz|2006}}{{sfn|Buschmann||Varela||Hernández-González|2008}} Research is investigating its use as feed for other [[aquaculture]] species such as shrimp.{{sfn|Buschmann||Varela||Hernández-González|2008}}<ref name="Cruz ''et al.'' 2009">Cruz ''et al.'' 2009</ref>


[[China]] and [[Chile]] are the largest producers of aquatic plants, each producing over 300,000 tonnes in 2007.<ref name="Fishery and Aquaculture Statistics[[FAO]] 2007 Handbook">FAO 2007</ref> How much of this total can be attributed to ''M. pyrifera'' is unclear.<ref name="Fishery and Aquaculture Statistics[[FAO]] 2007 Handbook" /> Both countries culture a variety of species, in Chile 50% of the production involves [[Phaeophyte|''Phaeophytes'']] and the other 50% is ''[[Rhodophytes]]''.<ref name="Buschmann ''et al.'' 2005">Buschmann ''et al.'' 2005</ref> China produces a larger variety of seaweeds including [[chlorophytes]].<ref name="Chaoyuan and Guangheng 1987">Chaoyuan and Guangheng 1987</ref> Experiments in Chile are exploring hybrids between ''M. pyrifera'' and ''[[Macrocystis integrifolia|M. integrifolia]]''.{{sfn| Westermeier|Patino||Piel|2006a}}
[[China]] and [[Chile]] are the largest producers of aquatic plants, each producing over 300,000 tonnes in 2007.<ref name="Fishery and Aquaculture Statistics[[FAO]] 2007 Handbook">FAO 2007</ref> How much of this total can be attributed to ''M. pyrifera'' is unclear.<ref name="Fishery and Aquaculture Statistics[[FAO]] 2007 Handbook" /> Both countries culture a variety of species, in Chile 50% of the production involves [[Phaeophyte|''Phaeophytes'']] and the other 50% is ''[[Rhodophytes]]''.{{sfn|Buschmann|Hernández-González||Astudillo|2005}} China produces a larger variety of seaweeds including [[chlorophytes]].<ref name="Chaoyuan and Guangheng 1987">Chaoyuan and Guangheng 1987</ref> Experiments in Chile are exploring hybrids between ''M. pyrifera'' and ''[[Macrocystis integrifolia|M. integrifolia]]''.{{sfn| Westermeier|Patino||Piel|2006a}}


==Culturing methods==
==Culturing methods==
The most common method of cultivating ''M. pyrifera'' was developed in China in the 1950s called the long line cultivation system, where the sporelings are produced in a cooled water greenhouse and then later planted out in the ocean attached to long lines.<ref name = "Mariculture of Seaweeds">Mariculture of Seaweeds</ref> The depth to which they are grown is varied in different countries.
The most common method of cultivating ''M. pyrifera'' was developed in China in the 1950s called the long line cultivation system, where the sporelings are produced in a cooled water greenhouse and then later planted out in the ocean attached to long lines.<ref name = "Mariculture of Seaweeds">Mariculture of Seaweeds</ref> The depth to which they are grown is varied in different countries.
Since this species has an [[alternation of generations]] in its life cycle, which involves a large [[sporophyte]] and a microscopic gametophyte. The sporophyte is what is harvested as seaweed. The mature [[sporophyte]] form the [[reproductive]] organs called [[Sorus|sori]], these are found on the underside of the leaves and produce the motile [[zoospores]] that germinate into the gametophyte.<ref name="Mondragon and Mondragon 03">Mondragon & Mondragon 2003</ref><ref name="Prescott">Prescott 1968, pp.226-227</ref> To induce sporalation, the selected plants are dried from a couple to up to twelve hours and placed in a seeding container filled with cool seawater of about 9-10&nbsp;°C; salinity of 30% and a pH of 7.8-7.9.<ref name="Buschmann ''et al.'' 2005"/><ref name = "Mariculture of Seaweeds"/><ref name = "Westermeier ''et al.'' 2006">Westermeier ''et al.'' 2006</ref> Photoperiod is also controlled for during the sporolation and the growth phases. A [[synthetic fiber|synthetic]] twine of about 2 – 6mm in diameter is placed on the bottom of the same container after sporalation and the released zoospores attach themselves to the twine and begin to geminate into male and female [[gametophytes]].<ref name="Buschmann ''et al.'' 2005"/><ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/> Upon maturity these gametophytes release sperm and egg cells that fuse in the water column and attach themselves to the same substrate as the gametophytes (i.e. the synthetic twine).<ref name="Buschmann ''et al.'' 2005"/><ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/> These plants are then reared up into young sporophyte plants for up to 60 days.<ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/>
Since this species has an [[alternation of generations]] in its life cycle, which involves a large [[sporophyte]] and a microscopic gametophyte. The sporophyte is what is harvested as seaweed. The mature [[sporophyte]] form the [[reproductive]] organs called [[Sorus|sori]], these are found on the underside of the leaves and produce the motile [[zoospores]] that germinate into the gametophyte.<ref name="Mondragon and Mondragon 03">Mondragon & Mondragon 2003</ref><ref name="Prescott">Prescott 1968, pp.226-227</ref> To induce sporalation, the selected plants are dried from a couple to up to twelve hours and placed in a seeding container filled with cool seawater of about 9-10&nbsp;°C; salinity of 30% and a pH of 7.8-7.9.{{sfn|Buschmann|Hernández-González||Astudillo|2005}<ref name = "Mariculture of Seaweeds"/><ref name = "Westermeier ''et al.'' 2006">Westermeier ''et al.'' 2006</ref> Photoperiod is also controlled for during the sporolation and the growth phases. A [[synthetic fiber|synthetic]] twine of about 2 – 6mm in diameter is placed on the bottom of the same container after sporalation and the released zoospores attach themselves to the twine and begin to geminate into male and female [[gametophytes]].{{sfn|Buschmann|Hernández-González||Astudillo|2005}<ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/> Upon maturity these gametophytes release sperm and egg cells that fuse in the water column and attach themselves to the same substrate as the gametophytes (i.e. the synthetic twine).{{sfn|Buschmann|Hernández-González||Astudillo|2005}<ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/> These plants are then reared up into young sporophyte plants for up to 60 days.<ref name = "Mariculture of Seaweeds"/><ref name="Westermeier ''et al.'' 2006"/>


These strings are either wrapped around or are cut up into small pieces and attached to a larger diameter cultivation rope. The cultivation ropes vary but are approximately 60m with floating [[buoy]]s attached.<ref name="Buschmann ''et al.'' 2005"/> The depths at which they are grown in the water column vary for some of the countries. In [[China]], ''M. pyrifera'' is cultivated on the surface with floating buoys attached every 2-3m and the ends of the rope attached to a wooden peg anchored to the substrate, individual ropes are usually hung at 50&nbsp;cm intervals to each other.<ref name = "Mariculture of Seaweeds"/> In Chile however ''M. pyrifera'' is grown at a depth of 2m using buoys to keep the plants at a constant depths.<ref name="Westermeier ''et al.'' 2006"/> These are then left alone to grow until ready to harvest.
These strings are either wrapped around or are cut up into small pieces and attached to a larger diameter cultivation rope. The cultivation ropes vary but are approximately 60m with floating [[buoy]]s attached.{{sfn|Buschmann|Hernández-González||Astudillo|2005} The depths at which they are grown in the water column vary for some of the countries. In [[China]], ''M. pyrifera'' is cultivated on the surface with floating buoys attached every 2-3m and the ends of the rope attached to a wooden peg anchored to the substrate, individual ropes are usually hung at 50&nbsp;cm intervals to each other.<ref name = "Mariculture of Seaweeds"/> In Chile however ''M. pyrifera'' is grown at a depth of 2m using buoys to keep the plants at a constant depths.<ref name="Westermeier ''et al.'' 2006"/> These are then left alone to grow until ready to harvest.
There are several problems with this method of cultivation as there are difficulties that lay in the management form the transition in the juvenile stages; from spore the gametophyte and [[embryonic]] sporophyte which are all done on a land based facility with careful control of water flow, temperature, nutrients, and light.<ref name = "Mariculture of Seaweeds"/> The [[Japan]]ese use a force cultivation method where a 2-year growth rate is achieved within a single growing season by controlling for the above requirements.<ref name = "Mariculture of Seaweeds"/>
There are several problems with this method of cultivation as there are difficulties that lay in the management form the transition in the juvenile stages; from spore the gametophyte and [[embryonic]] sporophyte which are all done on a land based facility with careful control of water flow, temperature, nutrients, and light.<ref name = "Mariculture of Seaweeds"/> The [[Japan]]ese use a force cultivation method where a 2-year growth rate is achieved within a single growing season by controlling for the above requirements.<ref name = "Mariculture of Seaweeds"/>


Line 24: Line 24:


===Harvesting===
===Harvesting===
The duration of the cultivation is varied upon the region and intensity of the farming, this species is usually harvested after two growth seasons (2 years).<ref name="Buschmann ''et al.'' 2005"/><ref name = "Mariculture of Seaweeds"/> For ''M. pyrifera'' that is artificially cultivated on ropes, they are harvested by a pulley system that is attached on boats that pull the individual lines on the vessels for cleaning.<ref name="Buschmann ''et al.'' 2005"/><ref name = "Mariculture of Seaweeds"/> Other countries such as the [[United States of America]] (USA) which rely primarily on naturally grown ''M. pyrifera'' use boats to harvest the surface canopy, the surface canopy is harvested several times per year. This is possible due to the fast growth of this species and the vegetative and reproductive parts are left undamaged.<ref name = "Bushing 2000"/><ref>Hoek ''et al.'' 1995, p.170</ref>
The duration of the cultivation is varied upon the region and intensity of the farming, this species is usually harvested after two growth seasons (2 years).{{sfn|Buschmann|Hernández-González||Astudillo|2005}<ref name = "Mariculture of Seaweeds"/> For ''M. pyrifera'' that is artificially cultivated on ropes, they are harvested by a pulley system that is attached on boats that pull the individual lines on the vessels for cleaning.{{sfn|Buschmann|Hernández-González||Astudillo|2005}<ref name = "Mariculture of Seaweeds"/> Other countries such as the [[United States of America]] (USA) which rely primarily on naturally grown ''M. pyrifera'' use boats to harvest the surface canopy, the surface canopy is harvested several times per year. This is possible due to the fast growth of this species and the vegetative and reproductive parts are left undamaged.<ref name = "Bushing 2000"/><ref>Hoek ''et al.'' 1995, p.170</ref>


==Control==
==Control==
Line 37: Line 37:
==Notes==
==Notes==
{{reflist|32em}}
{{reflist|32em}}
<

==References==
==References==
{{refbegin|2}}
{{refbegin|2}}
* Abbott, I A & G J Hollenberg. (1976) ''Marine Algae of California.'' California: Stanford University Press. {{ISBN|0-8047-0867-3}}
* Abbott, I A & G J Hollenberg. (1976) ''Marine Algae of California.'' California: Stanford University Press. {{ISBN|0-8047-0867-3}}
* Abbott, I. A. (1996). Ethnobotany of seaweeds: clues to uses of seaweeds. ''Hydrobiologia'', 326-327(1), 15-20.
* {{Cite journal|last=Abbott|first=Isabella A.|date=July 1996|title=Ethnobotany of seaweeds: clues to uses of seaweeds|url=http://link.springer.com/10.1007/BF00047782|journal=Hydrobiologia|language=en|volume=326-327|issue=1|pages=15–20|doi=10.1007/bf00047782|issn=0018-8158|ref=harv}}
* Agardh, C A. (1820) ''Species algarum rite cognitae, cum synonymis, differentiis specificis et descriptionibus succinctis.'' Vol. 1, Part 1, pp. [i-iv], [1]-168. Lund: Berling.
* Agardh, C A. (1820) ''Species algarum rite cognitae, cum synonymis, differentiis specificis et descriptionibus succinctis.'' Vol. 1, Part 1, pp. [i-iv], [1]-168. Lund: Berling.
* Buschmann, A., Varela, D., Hernández-González, M., & Huovinen, P. (2008). Opportunities and challenges for the development of an integrated seaweed-based aquaculture activity in Chile: determining the physiological capabilities of ''Macrocystis'' and ''Gracilaria'' as biofilters. ''Journal of Applied Phycology, 20''(5), 571-577.
* {{Cite journal|last=Buschmann|first=Alejandro H.|last2=Varela|first2=Daniel A.|last3=Hernández-González|first3=María Carmen|last4=Huovinen|first4=Pirjo|date=2008-01-09|title=Opportunities and challenges for the development of an integrated seaweed-based aquaculture activity in Chile: determining the physiological capabilities of Macrocystis and Gracilaria as biofilters|url=http://link.springer.com/10.1007/s10811-007-9297-x|journal=Journal of Applied Phycology|language=en|volume=20|issue=5|pages=571–577|doi=10.1007/s10811-007-9297-x|issn=0921-8971|ref=harv}}
* Buschmann, A. H., Hernández-González, M. C., Astudillo, C., Fuente, L. d. l., Gutierrez, A., & Aroca, G. (2005). Seaweed cultivation, product development and integrated aquaculture studies in Chile. ''World Aquaculture, 36''(3), 51-53.
* {{Cite journal|last=Buschmann|first=Alejandro|last2=Hernández-González|first2=María|last3=Astudillo|first3=C|last4=De La Fuente|first4=Lucia|last5=Gutierrez|first5=Alfonso|last6=Aroca|first6=Gesica|date=2005-09-01|title=Seaweed cultivation, product development and integrated aquaculture studies in Chile|url=https://www.researchgate.net/publication/285704013_Seaweed_cultivation_product_development_and_integrated_aquaculture_studies_in_Chile|journal=World Aquaculture|volume=36|pages=51–53|ref=harv}}
* Bushing, William W (2000) [http://www.starthrower.org/research/kelpmisc/kelp_mp.htm ''Giant Bladder Kelp ''].
* Bushing, William W (2000) [http://www.starthrower.org/research/kelpmisc/kelp_mp.htm ''Giant Bladder Kelp ''].
* {{Cite journal|last=Druehl|first=L. D.|last2=Baird|first2=R.|last3=Lindwall|first3=A.|last4=Lloyd|first4=K. E.|last5=Pakula|first5=S.|date=July 1988|title=Longline cultivation of some Laminariaceae in British Columbia, Canada|url=http://doi.wiley.com/10.1111/j.1365-2109.1988.tb00428.x|journal=Aquaculture Research|language=en|volume=19|issue=3|pages=253–263|doi=10.1111/j.1365-2109.1988.tb00428.x|issn=1355-557X|ref=harv}}
* {{Cite journal|last=Druehl|first=L. D.|last2=Baird|first2=R.|last3=Lindwall|first3=A.|last4=Lloyd|first4=K. E.|last5=Pakula|first5=S.|date=July 1988|title=Longline cultivation of some Laminariaceae in British Columbia, Canada|url=http://doi.wiley.com/10.1111/j.1365-2109.1988.tb00428.x|journal=Aquaculture Research|language=en|volume=19|issue=3|pages=253–263|doi=10.1111/j.1365-2109.1988.tb00428.x|issn=1355-557X|ref=harv}}

Revision as of 23:27, 19 July 2018

Giant kelp

Aquaculture of giant kelp, Macrocystis pyrifera, is the cultivation of kelp for uses such as food, dietary supplements or potash.[1][2] Giant kelp contains compounds such as iodine, potassium, other minerals vitamins and carbohydrates.[3][4]

History

At the beginning of the 20th century California kelp beds were harvested for their potash.[1][5][6] Commercial interest increased during the 1970s and the 1980s due to the production of alginates, and also for biomass production for animal feed due to the energy crisis.[5][6]{{sfn Gerard|1987}} However commercial production for M. pyrifera never became a reality. With the end of the energy crisis and the decline in alginate prices, research into farming Macrocystis declined.[2]

The supply of M. pyrifera for alginate production relied heavily on restoration and management of natural beds during the early 1990s.[2][7] Other functions such as substrate stabilization were explored in California, where the “Kelp bed project” transplanted 3-6m adult specimens to increase the stability of the harbor and promote diversity.[7][8]

Twenty-first century

The demand for M. pyrifera increased due to newfound uses such as fertilizers, bioremediation, and as feed for abalone and sea urchins.[2][7] Research is investigating its use as feed for other aquaculture species such as shrimp.[7][9]

China and Chile are the largest producers of aquatic plants, each producing over 300,000 tonnes in 2007.[10] How much of this total can be attributed to M. pyrifera is unclear.[10] Both countries culture a variety of species, in Chile 50% of the production involves Phaeophytes and the other 50% is Rhodophytes.[11] China produces a larger variety of seaweeds including chlorophytes.[12] Experiments in Chile are exploring hybrids between M. pyrifera and M. integrifolia.[13]

Culturing methods

The most common method of cultivating M. pyrifera was developed in China in the 1950s called the long line cultivation system, where the sporelings are produced in a cooled water greenhouse and then later planted out in the ocean attached to long lines.[14] The depth to which they are grown is varied in different countries. Since this species has an alternation of generations in its life cycle, which involves a large sporophyte and a microscopic gametophyte. The sporophyte is what is harvested as seaweed. The mature sporophyte form the reproductive organs called sori, these are found on the underside of the leaves and produce the motile zoospores that germinate into the gametophyte.[15][16] To induce sporalation, the selected plants are dried from a couple to up to twelve hours and placed in a seeding container filled with cool seawater of about 9-10 °C; salinity of 30% and a pH of 7.8-7.9.{{sfn|Buschmann|Hernández-González||Astudillo|2005}[14][17] Photoperiod is also controlled for during the sporolation and the growth phases. A synthetic twine of about 2 – 6mm in diameter is placed on the bottom of the same container after sporalation and the released zoospores attach themselves to the twine and begin to geminate into male and female gametophytes.{{sfn|Buschmann|Hernández-González||Astudillo|2005}[14][17] Upon maturity these gametophytes release sperm and egg cells that fuse in the water column and attach themselves to the same substrate as the gametophytes (i.e. the synthetic twine).{{sfn|Buschmann|Hernández-González||Astudillo|2005}[14][17] These plants are then reared up into young sporophyte plants for up to 60 days.[14][17]

These strings are either wrapped around or are cut up into small pieces and attached to a larger diameter cultivation rope. The cultivation ropes vary but are approximately 60m with floating buoys attached.{{sfn|Buschmann|Hernández-González||Astudillo|2005} The depths at which they are grown in the water column vary for some of the countries. In China, M. pyrifera is cultivated on the surface with floating buoys attached every 2-3m and the ends of the rope attached to a wooden peg anchored to the substrate, individual ropes are usually hung at 50 cm intervals to each other.[14] In Chile however M. pyrifera is grown at a depth of 2m using buoys to keep the plants at a constant depths.[17] These are then left alone to grow until ready to harvest. There are several problems with this method of cultivation as there are difficulties that lay in the management form the transition in the juvenile stages; from spore the gametophyte and embryonic sporophyte which are all done on a land based facility with careful control of water flow, temperature, nutrients, and light.[14] The Japanese use a force cultivation method where a 2-year growth rate is achieved within a single growing season by controlling for the above requirements.[14]

In China a project for offshore or deep water cultivation was also looked at where various farm structures were designed to facilitate the growth of M. pyrifera; nutrients from the deep waters were pumped up into the growing kelps.[14] The greatest benefit for this approach was that the algae were released from size constrains that are found in shallow waters. Issues with operational and farm designs plagued the project for deep water cultivation, and prevented further cultivation in this manner.[14]

Harvesting

The duration of the cultivation is varied upon the region and intensity of the farming, this species is usually harvested after two growth seasons (2 years).{{sfn|Buschmann|Hernández-González||Astudillo|2005}[14] For M. pyrifera that is artificially cultivated on ropes, they are harvested by a pulley system that is attached on boats that pull the individual lines on the vessels for cleaning.{{sfn|Buschmann|Hernández-González||Astudillo|2005}[14] Other countries such as the United States of America (USA) which rely primarily on naturally grown M. pyrifera use boats to harvest the surface canopy, the surface canopy is harvested several times per year. This is possible due to the fast growth of this species and the vegetative and reproductive parts are left undamaged.[3][18]

Control

In the UK, legislation defines giant kelp as a plant which should not be allowed to grow in the wild and these kelp are mechanically removed.[19]

See also

Notes

  1. ^ a b Abbott 1996.
  2. ^ a b c d Gutierrez et al. 2006.
  3. ^ a b Bushing 2000
  4. ^ Connor 1989, p. 58
  5. ^ a b Neushul 1987.
  6. ^ a b Druehl, Baird & Lindwall 1988.
  7. ^ a b c d Buschmann et al. 2008.
  8. ^ Simenstad et al.1978
  9. ^ Cruz et al. 2009
  10. ^ a b FAO 2007
  11. ^ Buschmann et al. 2005.
  12. ^ Chaoyuan and Guangheng 1987
  13. ^ Westermeier et al. 2006a.
  14. ^ a b c d e f g h i j k l Mariculture of Seaweeds
  15. ^ Mondragon & Mondragon 2003
  16. ^ Prescott 1968, pp.226-227
  17. ^ a b c d e Westermeier et al. 2006
  18. ^ Hoek et al. 1995, p.170
  19. ^ Schedule 9 Wildlife and Countryside Act 1981

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References