東華大學圖書館 |

Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms./
作者:	Yi, Loh Jun.
面頁冊數:	1 online resource (183 pages)
附註:	Source: Dissertations Abstracts International, Volume: 84-04, Section: B.
Contained By:	Dissertations Abstracts International84-04B.
標題:	Plankton. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29352391click for full text (PQDT)
ISBN:	9798352685211

Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms.
Yi, Loh Jun.

Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms. - 1 online resource (183 pages)

Source: Dissertations Abstracts International, Volume: 84-04, Section: B.

Thesis (Ph.D.)--National University of Singapore (Singapore), 2022.

Includes bibliographical references

Harmful algal blooms (HABs) are accumulations of phytoplankton that can lead to noxious outcomes in coastal waters. Dinoflagellates are known causative organisms. They include the athecate dinoflagellates which are known to cause fish-kills. Bloom-formation strategies of athecate dinoflagellates are not well understood. These dinoflagellates have demonstrated wide environmental tolerance, with their geographical distributions expanding over recent years. Most small, athecate dinoflagellates characteristically have lower abilities to directly compete for nutrient resources. Yet, harmful blooms of small athecate dinoflagellates are occurring more frequently, suggesting bloom-formation strategies that require investigation. Nitrogen is known to be a major driver of HABs, and pertinent to the Southeast Asian (SEA) region, due to the prevalence of nitrogen-pollutants. Coastal waters surrounding Singapore are also eutrophic, owing to their physical connection to urbanised terrain and host to heavy shipping activity. To establish a baseline, this thesis examined the role of nitrogen supply as a driver for athecate dinoflagellate blooms, in both culture and field-based studies. The roles of interspecific interactions in multi-species blooms were also investigated. The athecate dinoflagellate Takayama acrotrocha, was isolated from Johor Strait and examined for its nitrogen preferences. Takayama acrotrocha was found to prefer high concentrations of inorganic nitrogen forms, ammonium, and nitrate for growth. Ammonium induced the highest growth rates out of the nitrogen forms tested. Differences in uptake strategies between nitrogen forms by T. acrotrocha were also observed. Interspecific interactions between T. acrotrocha and three other phytoplankton species, isolated from the Johor Strait varied. Takayama acrotrocha and another athecate dinoflagellate, Karlodinium ballantinum, could co-occur at high cell concentrations, under high nitrate concentrations. In contrast, the growth rate of T. acrotrocha was suppressed in the presence of the red tide thecate dinoflagellate, Scrippsiella acuminata. The suppression was attributed to high nitrogen acquisition rates of S. acuminata. Takayama acrotrocha was also suppressed by the chain-forming diatom, Skeletonema tropicum, while nitrogen was still available. This suggested allelopathic effects of S. tropicum, shortening the T. acrotrocha growth phase and reducing its growth rates. Nitrogen-driven changes in the composition of phytoplankton was assessed in the field environment via in-situ experimentation. Two tropical coasts were compared to elucidate the influence of urban-eutrophic versus natural-oligotrophic coastal conditions on the response of each phytoplankton community. Nitrogen supply and interspecific interactions were important for species selection and growth outcomes. Distinct preference for nitrogen forms were observed. When the preference for high nitrate concentrations overlapped between the nontoxin producing diatoms and athecate dinoflagellates, the latter group was able to proliferate, due to the suppression of faster-growing diatoms. Growth response times of the phytoplankton assemblages differed between the two field sites. Phytoplankton from the urban-eutrophic field site responded rapidly to the nitrogen spiking, while the phytoplankton community from the natural-oligotrophic site exhibited a lag phase. This thesis highlighted the unique responses of small athecate dinoflagellates to nitrogen. Small athecate dinoflagellates characterised with slow growth rates, are likely to utilise alternative strategies for bloom formation. This includes the requirement for faster-growing, more competitive species to be suppressed, and the continuous supply of nitrogen to maintain high cell concentrations, as observed in T. acrotrocha. Such nitrogen-pollution regimes can be observed in the coastal waters of Singapore and within SEA. Robust monitoring of coastal nitrogen profiles is therefore essential, but insufficient on its own to manage the bloom risk of Kareniaceae dinoflagellates. This thesis also emphasised the importance of interspecific interactions for bloom prediction and mitigation plans.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798352685211Subjects--Topical Terms:

1299572
Plankton.
Index Terms--Genre/Form:

542853
Electronic books.

Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms.
LDR:05650nmm a2200421K 4500 001 2354931
005 20230505090503.5
006 m o d
007 cr mn ---uuuuu
008 241011s2022 xx obm 000 0 eng d
020 $a 9798352685211
035 $a (MiAaPQ)AAI29352391
035 $a (MiAaPQ)USingapore226217
035 $a AAI29352391
040 $a MiAaPQ $b eng $c MiAaPQ $d NTU
100 1 $a Yi, Loh Jun. $3 3695306
245 1 0 $a Nitrogen-Induced Responses of Tropical Athecate Dinoflagellates in Harmful Algal Blooms.
264 0 $c 2022
300 $a 1 online resource (183 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 84-04, Section: B.
500 $a Advisor: Man, Wong Sek; Yew, Sandric Leong Chee.
502 $a Thesis (Ph.D.)--National University of Singapore (Singapore), 2022.
504 $a Includes bibliographical references
520 $a Harmful algal blooms (HABs) are accumulations of phytoplankton that can lead to noxious outcomes in coastal waters. Dinoflagellates are known causative organisms. They include the athecate dinoflagellates which are known to cause fish-kills. Bloom-formation strategies of athecate dinoflagellates are not well understood. These dinoflagellates have demonstrated wide environmental tolerance, with their geographical distributions expanding over recent years. Most small, athecate dinoflagellates characteristically have lower abilities to directly compete for nutrient resources. Yet, harmful blooms of small athecate dinoflagellates are occurring more frequently, suggesting bloom-formation strategies that require investigation. Nitrogen is known to be a major driver of HABs, and pertinent to the Southeast Asian (SEA) region, due to the prevalence of nitrogen-pollutants. Coastal waters surrounding Singapore are also eutrophic, owing to their physical connection to urbanised terrain and host to heavy shipping activity. To establish a baseline, this thesis examined the role of nitrogen supply as a driver for athecate dinoflagellate blooms, in both culture and field-based studies. The roles of interspecific interactions in multi-species blooms were also investigated. The athecate dinoflagellate Takayama acrotrocha, was isolated from Johor Strait and examined for its nitrogen preferences. Takayama acrotrocha was found to prefer high concentrations of inorganic nitrogen forms, ammonium, and nitrate for growth. Ammonium induced the highest growth rates out of the nitrogen forms tested. Differences in uptake strategies between nitrogen forms by T. acrotrocha were also observed. Interspecific interactions between T. acrotrocha and three other phytoplankton species, isolated from the Johor Strait varied. Takayama acrotrocha and another athecate dinoflagellate, Karlodinium ballantinum, could co-occur at high cell concentrations, under high nitrate concentrations. In contrast, the growth rate of T. acrotrocha was suppressed in the presence of the red tide thecate dinoflagellate, Scrippsiella acuminata. The suppression was attributed to high nitrogen acquisition rates of S. acuminata. Takayama acrotrocha was also suppressed by the chain-forming diatom, Skeletonema tropicum, while nitrogen was still available. This suggested allelopathic effects of S. tropicum, shortening the T. acrotrocha growth phase and reducing its growth rates. Nitrogen-driven changes in the composition of phytoplankton was assessed in the field environment via in-situ experimentation. Two tropical coasts were compared to elucidate the influence of urban-eutrophic versus natural-oligotrophic coastal conditions on the response of each phytoplankton community. Nitrogen supply and interspecific interactions were important for species selection and growth outcomes. Distinct preference for nitrogen forms were observed. When the preference for high nitrate concentrations overlapped between the nontoxin producing diatoms and athecate dinoflagellates, the latter group was able to proliferate, due to the suppression of faster-growing diatoms. Growth response times of the phytoplankton assemblages differed between the two field sites. Phytoplankton from the urban-eutrophic field site responded rapidly to the nitrogen spiking, while the phytoplankton community from the natural-oligotrophic site exhibited a lag phase. This thesis highlighted the unique responses of small athecate dinoflagellates to nitrogen. Small athecate dinoflagellates characterised with slow growth rates, are likely to utilise alternative strategies for bloom formation. This includes the requirement for faster-growing, more competitive species to be suppressed, and the continuous supply of nitrogen to maintain high cell concentrations, as observed in T. acrotrocha. Such nitrogen-pollution regimes can be observed in the coastal waters of Singapore and within SEA. Robust monitoring of coastal nitrogen profiles is therefore essential, but insufficient on its own to manage the bloom risk of Kareniaceae dinoflagellates. This thesis also emphasised the importance of interspecific interactions for bloom prediction and mitigation plans.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
650 4 $a Plankton. $3 1299572
650 4 $a Nitrates. $3 914879
650 4 $a Amino acids. $3 558768
650 4 $a Population growth. $3 3562887
650 4 $a Biomass. $3 1013462
650 4 $a Coasts. $3 545629
650 4 $a Nitrogen. $3 1314426
650 4 $a Eutrophication. $3 896350
650 4 $a Poisoning. $3 770903
650 4 $a Algae. $3 546231
650 4 $a Microscopy. $3 540544
650 4 $a Shellfish. $3 2147548
650 4 $a Taxonomy. $3 3556303
650 4 $a Microorganisms. $3 666946
650 4 $a Metabolites. $3 683644
650 4 $a Morphology. $3 591167
650 4 $a Toxins. $3 789124
650 4 $a Pollution. $3 518679
650 4 $a Cell division. $3 816756
650 4 $a Fish. $3 3564374
650 4 $a Animal sciences. $3 3174829
650 4 $a Biogeochemistry. $3 545717
650 4 $a Biological oceanography. $3 2122748
650 4 $a Biology. $3 522710
650 4 $a Cellular biology. $3 3172791
650 4 $a Chemistry. $3 516420
650 4 $a Developmental biology. $3 592588
650 4 $a Microbiology. $3 536250
655 7 $a Electronic books. $2 lcsh $3 542853
690 $a 0287
690 $a 0475
690 $a 0425
690 $a 0416
690 $a 0306
690 $a 0379
690 $a 0485
690 $a 0758
690 $a 0410
710 2 $a ProQuest Information and Learning Co. $3 783688
710 2 $a National University of Singapore (Singapore). $3 3352228
773 0 $t Dissertations Abstracts International $g 84-04B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29352391 $z click for full text (PQDT)