Aquatic Botany最新文献

{"title":"Fecundity and egg viability of Sargassum oligocystum Montagne, 1845 in Iligan Bay, Northern Mindanao, Philippines","authors":"Maria Lyn M. Magcanta-Mortos ,&nbsp;Wilfredo H. Uy ,&nbsp;Lovella R. Calala ,&nbsp;Venus E. Leopardas ,&nbsp;Danilo B. Largo","doi":"10.1016/j.aquabot.2023.103740","DOIUrl":"10.1016/j.aquabot.2023.103740","url":null,"abstract":"<div><p><span>Fertile thalli of </span><span><em>Sargassum</em><em> oligocystum</em></span> were collected from the intertidal area of Naawan, Misamis Oriental, in northern Mindanao, Philippines. The early development, fecundity, egg viability, and recruitment of <em>S. oligocystum</em> were studied to gain insights into the species' biology in preparation for its future ecological and commercial applications. The embryonic development of <em>S. oligocystum</em> followed almost the same pattern as other <em>Sargassum</em><span><span> species found in the literature: 1) the presence of unfertilized eight-nuclei eggs, 2) zygotes undergoing division into embryos after fertilization, and 3) the development of dense </span>rhizoids on embryos after 4–5 days from release. The fecundity of one thallus of </span><em>S. oligocystum</em> produced 0.5 million eggs and 746 ± 1.5 eggs per receptacle, with 94.72% viability of eggs developing rhizoids for attachment. Recruitment of zygotes ranged from 0.52 ind cm⁻² to 3.37 ind cm⁻², with clay bricks found to be the most suitable substrate with a significantly higher recruitment rate than nylon rope and plastic binder. The present study implies the high potential of producing <em>S. oligocystum</em><span> biomass through the mass production of seed stocks in the hatchery.</span></p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"191 ","pages":"Article 103740"},"PeriodicalIF":1.8,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138563355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon limitation and aluminium toxicity prevents dominance of Crassula helmsii on weakly buffered soils","authors":"J. van Doorn (Jelmer) ,&nbsp;E.C.H.E.T. Lucassen (Esther) ,&nbsp;M.I.J.T. van Roosmalen (Michael) ,&nbsp;A.J.P. Smolders (Fons)","doi":"10.1016/j.aquabot.2023.103737","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103737","url":null,"abstract":"<div><p><span>Invasions of the aquatic weed </span><span><em>Crassula</em><em> helmsii</em></span> pose a serious threat to native vegetation of soft water lakes, which increases the need for understanding the factors that regulate the success or failure of <em>C. helmsii</em>. Creating favorable conditions for native species seems promising to control <em>C. helmsii</em>, as previous research indicated that <em>C. helmsii</em> is a poor (root) competitor. We studied the development of <em>C. helmsii</em> growing together with the native <em>Littorella uniflora</em> (biomass, cover, tissue nutrient composition) at two different calcareous poor soil types (organic/acid, mineral/buffered) and under two different water tables (not inundated, submerged) in a greenhouse experiment. We found that when growing under submerged conditions, <em>C. helmsii</em> coexisted with <em>L. uniflora</em> and other native species without becoming dominant due to carbon limitation in the water layer. In contrast, we found that <em>C. helmsii</em> can easily become dominant over <em>L. uniflora</em> when growing on desiccated buffered fen soils with moderate nutrient availability. On the acidic/organic soils, <em>C. helmsii</em> development was poor and die-off was observed under both water level treatments, probably induced due to aluminum toxicity under a low acidity. These results indicate that creating oligotrophic and carbon-poor conditions are required for controlling <em>C. helmsii</em><span>. Restoration measures can preferably be taken before the onset of the rainy season and/or be followed by maintenance of a temporal artificial high water table to stimulate carbon limitation. Liming more or less organic shores could alleviate aluminum toxicity under acidic conditions which can potentially stimulate the development of </span><em>C. helmsii.</em></p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"191 ","pages":"Article 103737"},"PeriodicalIF":1.8,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138490755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between arsenic content and macroelements, microelements, and polysaccharides in Sargassum horridum (Ochrophyta, Phaeophyceae) in the Gulf of California, Mexico","authors":"Alejandra Mazariegos-Villarreal ,&nbsp;Elisa Serviere-Zaragoza ,&nbsp;Juan Manuel López-Vivas ,&nbsp;Yolanda Freile-Pelegrín ,&nbsp;Héctor Reyes-Bonilla ,&nbsp;Karla León-Cisneros ,&nbsp;Jobst Wurl ,&nbsp;Lia Celina Méndez-Rodríguez","doi":"10.1016/j.aquabot.2023.103730","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103730","url":null,"abstract":"<div><p><span><em>Sargassum</em></span> species are known for their capacity to accumulate toxic elements, which may pose environmental risks and limit their use. Arsenic accumulation in <em>Sargassum</em> may vary in response to environmental and physiological conditions. Moreover, interactions between chemical elements may result in synergistic or antagonistic effects. This study determined the variability in the concentration of macroelements (N, P, K) and microelements (As, Cd, Pb, Cu, Zn, and Mn) through time and between growth stages in <em>Sargassum horridum</em><span> from a site adjacent to a phosphorite<span> deposit in the Gulf of California. A generalized linear model (GLM) was performed to assess the influence of other concurrent elements, polysaccharides (alginate and fucoidan), and their main functional groups (uronic acids and sulfate) on arsenic content. Elemental concentrations showed the following decreasing order: N &gt; K &gt; P &gt; Fe &gt; Mn &gt; Zn &gt; Cd &gt; As &gt; Cu &gt; Pb. Arsenic concentration was 4.33 ± 0.20 mg kg</span></span>^-1. Significant differences in element concentrations were found by month and growth stage. The main variables associated with arsenic accumulation in <em>S. horridum</em><span> were potassium, nitrogen, zinc, fucoidan, sulfate from fucoidan, and alginate. The implications of the arsenic, cadmium, and lead concentrations in </span><em>S. horridum</em> and its potential applications in food, feed, and agricultural contexts are discussed. This research sheds light on the dynamic nature of elements accumulation in <em>Sargassum,</em> emphasizing the need for a comprehensive and context-specific understanding of elemental variations within <em>Sargassum</em> for safe and responsible applications.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"191 ","pages":"Article 103730"},"PeriodicalIF":1.8,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138465951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and occupation strategy of Egeria najas (Hydrocharitaceae) in different habitats along the Upper Paraná River corridor","authors":"Léia Carolina Lucio ,&nbsp;Bárbara Scorsim ,&nbsp;Adrian Cesar da Silva ,&nbsp;Julia Naomi Morimoto de Carvalho ,&nbsp;Alessandra Valéria de Oliveira ,&nbsp;Karina Fidanza Rodrigues ,&nbsp;Sidinei Magela Thomaz ,&nbsp;Sônia Maria Alves Pinto Prioli ,&nbsp;Alberto José Prioli","doi":"10.1016/j.aquabot.2023.103729","DOIUrl":"10.1016/j.aquabot.2023.103729","url":null,"abstract":"<div><p><em>Egeria najas</em><span> is a submerged aquatic macrophyte native to South America, with high propagation in reservoirs and natural lakes, whose reproductive strategy is little known. Understanding the genetic diversity of macrophyte populations can provide important information about this species' dispersion and colonization strategies, and support management actions. We aimed to genetically characterize populations of </span><em>E. najas</em><span><span> that colonize reservoirs and natural aquatic habitats (in a floodplain) in the Upper Paraná River basin, using the molecular markers </span>ITS and </span><em>trnL-trnF</em>. The results showed the absence of genetic variation for the nuclear marker ITS and 13 distinct haplotypes for <em>trnL-trnF</em><span>. One of these haplotypes occurred in all habitats and 11 are unique haplotypes, of which 5 occurred in the Itaipu Reservoir and 6 in the floodplain. The null genetic diversity for the nuclear marker and the genetic homogeneity of the studied populations indicates that the reproduction of </span><em>E. najas</em><span> is mostly vegetative. The source of chloroplast marker haplotype variability may be somatic mutations<span>. The connectivity among aquatic environments associated with river flow favors the transport of aquatic macrophyte propagules to different habitats. In the case of </span></span><em>E. najas</em>, whose vegetative propagules regenerate easily, the frequency of migrations supports the low genetic variability observed in populations of the Upper Paraná. In addition, the ability to occupy new habitats and recolonize disturbed ones strongly indicates that <em>E. najas</em> populations follow the metapopulation dynamics.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"191 ","pages":"Article 103729"},"PeriodicalIF":1.8,"publicationDate":"2023-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135708810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Marine macrophyte strandings in the Yucatán peninsula: Citizen science as a potential tool for long-term monitoring","authors":"Erika Vázquez-Delfín ,&nbsp;Carmen Galindo-De Santiago ,&nbsp;Arely Paredes-Chi ,&nbsp;Ameyalli Ríos-Vázquez ,&nbsp;Ana Benavides-Lahnstein ,&nbsp;Kaysara Khatun ,&nbsp;Juliet Brodie","doi":"10.1016/j.aquabot.2023.103728","DOIUrl":"10.1016/j.aquabot.2023.103728","url":null,"abstract":"<div><p>Massive strandings of seaweeds on the eastern coasts of the Yucatán peninsula, Mexico have become a major socioecological problem, creating the need for establishing a baseline monitoring program in the region. A citizen science initiative, Big Seaweed Search Mexico (BSS-Mx), was developed to monitor temporal changes in the biomass stranded (abundance and species composition) in the Yucatán peninsula. The initiative was tested in two regions; Puerto Morelos, Quintana Roo, where massive strandings of <em>Sargassum</em> have caused severe socioecological impacts, and Sisal, Yucatán, where there is scarce information about the species composition of the strandings and their seasonal dynamics. Even the different socioeconomic and ecological context of these regions, the public participation in close collaboration with research scientists allowed detection of the temporal changes in the abundance and species composition of the strandings in both locations over a period of ten months. A total of 45 taxa were identified in Puerto Morelos, from which pelagic <em>Sargassum</em> and a seagrass were dominant for most time of the year; whereas 58 taxa were identified in Sisal, observing a higher diversity dominated by red seaweeds, with dominant taxa changing seasonally. The results represent baseline information that should be considered to develop management strategies and marine conservation actions according to each region. The findings highlight the role of citizen science as a potential tool to conduct large-scale and long-term monitoring and stimulate public participation to address environmental issues.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103728"},"PeriodicalIF":1.8,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001134/pdfft?md5=9358c06600fb82506320723f78a6c86e&pid=1-s2.0-S0304377023001134-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135515646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of seagrass (Halophila beccarii) from the mid-southern coast of Bangladesh, Bay of Bengal","authors":"Mohammed Ashraful Haque ,&nbsp;Md. Rahamat Ullah ,&nbsp;Md. Monjurul Hasan ,&nbsp;Aovijite Bosu ,&nbsp;Farhana Yasmin ,&nbsp;Md. Amirul Islam ,&nbsp;Yahia Mahmud","doi":"10.1016/j.aquabot.2023.103727","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103727","url":null,"abstract":"<div><p>This current investigation presents the very first evidence of the vulnerable ocean turf grass, <em>Halophila beccarii</em>, in the intertidal region of the Andharmanik River, mid-southern coast of Bangladesh, Bay of Bengal. It was found in the muddy and shallow section of the mangroves, dominated by <em>Sonneratia alba</em>, <em>Acanthus ilicifolius</em>, and <em>Avicennia marina</em>. The meadow had an average density of 652 ± 71 shoots/m². The presence of <em>H. beccarii</em> on Bangladesh's mid-southern coast is a positive indication of the enhanced health of the ecosystem. The presence of <em>H. beccarii</em> in this area will enhance water quality and sediment stability. This is the first record of any seagrass species on Bangladesh's mid-southern coast.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103727"},"PeriodicalIF":1.8,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001122/pdfft?md5=dfa8e8e930f1604b3cf2c09b1c7c2f7f&pid=1-s2.0-S0304377023001122-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92044950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproductive phenology of coralline algae Porolithon antillarum and Lithophyllum sp. under seasonal upwelling conditions, Colombian Caribbean","authors":"Félix Alvarado-Jiménez ,&nbsp;Natalia Rincón-Díaz ,&nbsp;Rocío García-Urueña","doi":"10.1016/j.aquabot.2023.103726","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103726","url":null,"abstract":"<div><p>Crustose coralline algae are a group of calcified algae that has an important ecological role in coral reefs, such as cementation and stabilization of the reef framework, as well as providing habitat and food for different marine associates. Among the common genera, <em>Lithophyllum</em> and <em>Porolithon</em> (Corallinales) are conspicuous components of the Santa Marta reef communities in the Colombian Caribbean. From December to April, this area is influenced by seasonal trade winds, a phenomenon that is related to the upwelling of subsurface waters that causes a decrease in temperature from ∼29 °C to ∼22 °C and pH from ∼ 8.5 to ∼8.0. The aim of this study was to evaluate the effect of upwelling and non-upwelling (2017, 2018, and 2021) on the reproductive phenology of <em>Lithophyllum</em> sp. and <em>Porolithon antillarum</em> based on counts of superficial conceptacles per cm² and a determination of the reproductive stages of the algae collected in Tayrona National Natural Park and Punta Venado, Santa Marta. The algae presented the highest number of mature conceptacles during the upwelling period for <em>P. antillarum</em> and <em>Lithophyllum</em> sp<em>.</em> (46 and 27 conceptacles cm², respectively). Moreover, the tetrasporangial stage was the most frequent in all the thalli, thus indicating the predominance of this phase in the reproductive cycle of the algae studied. These results are important as they indicate the influence of seasonality on the reproductive stages of CCA and bring the need to do more research into the influence of the environment on the physiological mechanisms that determine the changes in the life cycle of these algae.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103726"},"PeriodicalIF":1.8,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001110/pdfft?md5=20894e94f8f7f7112389bd35b2afae11&pid=1-s2.0-S0304377023001110-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92044948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding unique tolerance limits in Hydrocotyle verticillata: From submergence to water deficiency","authors":"Liudmyla Kozeko ,&nbsp;Yulia Ovcharenko ,&nbsp;Sigita Jurkonienė ,&nbsp;Elizabeth Kordyum","doi":"10.1016/j.aquabot.2023.103725","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103725","url":null,"abstract":"<div><p><em>Hydrocotyle verticillata</em> can tolerate varying degrees of flooding, up to complete submergence, and is at the same time extremely sensitive to drought. Understanding the structural and biochemical principles of these unusual tolerance limits is of particular importance. We analyzed the effect of soil flooding, complete submergence (rooted plants and floating stems), and dehydration on root anatomy, alcohol dehydrogenase (ADH), heat shock proteins 70 (HSP70), hydrogen peroxide, and DNA integrity using light microscopy, biochemical and histological methods. It was shown that anatomical traits of adventitious roots with a triarch stele were similar in the plants growing under different conditions; the single-layered and thin-walled epidermis formed relatively short root hairs; essential air spaces were absent in the cortex parenchyma. Results on ADH clearly showed that anaerobic energetic metabolism in root apices and individual rhizoderma cells of the mature root zone was normal for this species in optimal and suboptimal conditions, while leaves changed metabolism to anaerobic in response to submergence. Alterations in the protein spectrum were accompanied by adequate up-regulation of HSP70 under different levels of flooding and dehydration/rehydration. These results appear to indicate a flooding adaptation strategy for <em>H. verticillata</em> based primarily on metabolic plasticity rather than morphoanatomical adaptations. Most notably, the resistance of this species to long-term submergence has been associated with strong ADH induction in leaves, transient activation of 70 kDa isoform of HSP70 and induction of 66 kDa isoform, as well as a significant delay in the accumulation of hydrogen peroxide and DNA degradation.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103725"},"PeriodicalIF":1.8,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001109/pdfft?md5=42640be83446e88da085a932aebf89b7&pid=1-s2.0-S0304377023001109-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92044947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A systematic review of mechanistic models of riverine macrophyte growth","authors":"Lee H. Dietterich ,&nbsp;Suhey Ortiz Rosa ,&nbsp;Bianca R. Charbonneau ,&nbsp;S. Kyle McKay","doi":"10.1016/j.aquabot.2023.103724","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103724","url":null,"abstract":"<div><p>Riverine macrophytes play diverse and foundational ecological roles, directly influencing ecosystem properties from local biodiversity to flows of water, energy, nutrients, and sediment, many of which in turn are central to river management. Numerical modeling is thus a crucial tool for understanding macrophyte and ecosystem responses to environmental, ecological, or management changes. However, riverine macrophytes have received relatively limited modeling attention compared to plants in many other aquatic or terrestrial systems. We conducted a systematic review of riverine macrophyte growth models, focusing on mechanisms of macrophyte growth, biomass loss, and feedback effects on river ecosystems. Processes such as light availability, thermal tolerance, nutrient limitation, and mortality were widely included in almost all models meeting the review criteria. However, models varied widely in their inclusion of processes such as shading, scour, and the roles of macrophytes in stream nutrient cycles. There has been relatively little consideration of factors such as dispersal, carbon sources, herbivory, burial, desiccation, and competition for space or nutrients, indicating directions for future modeling work. In light of this, we present a conceptual framework to help guide future macrophyte growth modelers through a thorough consideration of macrophytes’ myriad interactions with their ecosystems. We also emphasize the importance of modularity and accessibility toward improving efforts to model, and in turn manage, riverine ecosystems.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103724"},"PeriodicalIF":1.8,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001092/pdfft?md5=30040bc4c9c2f86643483914fc65e7d0&pid=1-s2.0-S0304377023001092-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92044949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary explorations of environmental tolerances and growth rates of holopelagic Sargassum morphotypes","authors":"Jeffrey M. Schell ,&nbsp;Deborah S. Goodwin ,&nbsp;Rebecca H. Volk ,&nbsp;Amy N.S. Siuda","doi":"10.1016/j.aquabot.2023.103723","DOIUrl":"https://doi.org/10.1016/j.aquabot.2023.103723","url":null,"abstract":"<div><p>To predict spatial and temporal dynamics of macroalgal blooms, including the Great Atlantic <em>Sargassum</em> Belt, understanding the environmental tolerances and growth rates of different species under varying conditions is essential. A series of preliminary experiments were conducted exposing three common holopelagic <em>Sargassum</em> morphotypes to different temperature (21.6–30.6 °C) and salinity (26.2–40.0 psu) conditions. <em>Sargassum</em> tolerance was assessed by two methods: a Health Metric calculated daily from changes in a specimen’s blade and vesicle count and coloration patterns, and growth rates determined from pre- and post-treatment wet weights. Morphotypes exhibited different responses to treatment conditions. Health Metric values and growth rates for <em>S. fluitans III</em> were not significantly impacted by tested temperatures or salinities. <em>S. natans I</em> tolerated a wide range of temperatures but only moderate salinities. While <em>S. natans VIII</em> grew well and maintained strong Health Metrics across examined salinities, it was less tolerant of cold temperatures and exhibited overall lower growth rates than other morphotypes. Given inconsistent findings among recent growth rate studies, including this one, additional experiments of longer duration that continue to explore temperature and salinity effects and use specimens from across holopelagic <em>Sargassum’s</em> geographic range are necessary to understand growth ecology and parameterize models.</p></div>","PeriodicalId":8273,"journal":{"name":"Aquatic Botany","volume":"190 ","pages":"Article 103723"},"PeriodicalIF":1.8,"publicationDate":"2023-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304377023001080/pdfft?md5=96f87d6ee7e9348b708eebcaa417dfe3&pid=1-s2.0-S0304377023001080-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92044961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}