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  1 / 173 MEDLINE  
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[PMID]:29364902
[Au] Autor:Friedlander AM; Ballesteros E; Bell TW; Giddens J; Henning B; Hüne M; Muñoz A; Salinas-de-León P; Sala E
[Ad] Endereço:Pristine Seas, National Geographic Society, Washington DC, United States of America.
[Ti] Título:Marine biodiversity at the end of the world: Cape Horn and Diego Ramírez islands.
[So] Source:PLoS One;13(1):e0189930, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The vast and complex coast of the Magellan Region of extreme southern Chile possesses a diversity of habitats including fjords, deep channels, and extensive kelp forests, with a unique mix of temperate and sub-Antarctic species. The Cape Horn and Diego Ramírez archipelagos are the most southerly locations in the Americas, with the southernmost kelp forests, and some of the least explored places on earth. The giant kelp Macrocystis pyrifera plays a key role in structuring the ecological communities of the entire region, with the large brown seaweed Lessonia spp. forming dense understories. Kelp densities were highest around Cape Horn, followed by Diego Ramírez, and lowest within the fjord region of Francisco Coloane Marine Park (mean canopy densities of 2.51 kg m-2, 2.29 kg m-2, and 2.14 kg m-2, respectively). There were clear differences in marine communities among these sub-regions, with the lowest diversity in the fjords. We observed 18 species of nearshore fishes, with average species richness nearly 50% higher at Diego Ramírez compared with Cape Horn and Francisco Coloane. The number of individual fishes was nearly 10 times higher at Diego Ramírez and 4 times higher at Cape Horn compared with the fjords. Dropcam surveys of mesophotic depths (53-105 m) identified 30 taxa from 25 families, 15 classes, and 7 phyla. While much of these deeper habitats consisted of soft sediment and cobble, in rocky habitats, echinoderms, mollusks, bryozoans, and sponges were common. The southern hagfish (Myxine australis) was the most frequently encountered of the deep-sea fishes (50% of deployments), and while the Fueguian sprat (Sprattus fuegensis) was the most abundant fish species, its distribution was patchy. The Cape Horn and Diego Ramírez archipelagos represent some of the last intact sub-Antarctic ecosystems remaining and a recently declared large protected area will help ensure the health of this unique region.
[Mh] Termos MeSH primário: Biodiversidade
Biologia Marinha
[Mh] Termos MeSH secundário: Animais
Chile
Ecossistema
Peixes
Kelp
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189930


  2 / 173 MEDLINE  
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[PMID]:29298307
[Au] Autor:Witman JD; Lamb RW
[Ad] Endereço:Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, United States of America.
[Ti] Título:Persistent differences between coastal and offshore kelp forest communities in a warming Gulf of Maine.
[So] Source:PLoS One;13(1):e0189388, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Kelp forests provide important ecosystem services, yet coastal kelp communities are increasingly altered by anthropogenic impacts. Kelp forests in remote, offshore locations may provide an informative contrast due to reduced impacts from local stressors. We tested the hypothesis that shallow kelp assemblages (12-15 m depth) and associated fish and benthic communities in the coastal southwest Gulf of Maine (GOM) differed significantly from sites on Cashes Ledge, 145 km offshore by sampling five coastal and three offshore sites at 43.0 +/- 0.07° N latitude. Offshore sites on Cashes Ledge supported the greatest density (47.8 plants m2) and standing crop biomass (5.5 kg m2 fresh weight) of the foundation species Saccharina latissima kelp at this depth in the Western North Atlantic. Offshore densities of S. latissima were over 150 times greater than at coastal sites, with similar but lower magnitude trends for congeneric S. digitata. Despite these differences, S. latissima underwent a significant 36.2% decrease between 1987 and 2015 on Cashes Ledge, concurrent with a rapid warming of the GOM and invasion by the kelp-encrusting bryozoan Membranipora membranacea. In contrast to kelp, the invasive red alga Dasysiphonia japonica was significantly more abundant at coastal sites, suggesting light or dispersal limitation offshore. Spatial differences in fish abundance mirrored those of kelp, as the average biomass of all fish on Cashes Ledge was 305 times greater than at the coastal sites. Remote video censuses of cod (Gadus morhua), cunner (Tautaogolabrus adspersus), and pollock (Pollachius virens) corroborated these findings. Understory benthic communities also differed between regions, with greater abundance of sessile invertebrates offshore. Populations of kelp-consuming sea urchins Stronglyocentrotus droebachiensis, were virtually absent from Cashes Ledge while small urchins were abundant onshore, suggesting recruitment limitation offshore. Despite widespread warming of the GOM since 1987, extraordinary spatial differences in the abundance of primary producers (kelp), consumers (cod) and benthic communities between coastal and offshore sites have persisted. The shallow kelp forest communities offshore on Cashes Ledge represent an oasis of unusually high kelp and fish abundance in the region, and as such, comprise a persistent abundance hotspot that is functionally significant for sustained biological productivity of offshore regions of the Gulf of Maine.
[Mh] Termos MeSH primário: Ecossistema
Kelp
[Mh] Termos MeSH secundário: Animais
Biodiversidade
Biomassa
Cadeia Alimentar
Maine
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180104
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189388


  3 / 173 MEDLINE  
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[PMID]:28800586
[Au] Autor:Gonzales J; Tymon T; Küpper FC; Edwards MS; Carrano CJ
[Ad] Endereço:Department of Chemistry and Biochemistry, San Diego State University, San Diego, California, United States of America.
[Ti] Título:The potential role of kelp forests on iodine speciation in coastal seawater.
[So] Source:PLoS One;12(8):e0180755, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Kelps have a major role in marine and atmospheric iodine cycling in the coastal zone of temperate regions, with potential wide-ranging impacts on ozone destruction in the coastal marine boundary layer. However, little is known about the impact of kelp forests on iodine speciation in coastal sea water. To address this, we examined iodide and iodate concentrations in seawater in and around a giant kelp forest near San Diego, CA, USA, and a nearby site that was not influenced by kelp biology. Our data shows that while both iodide and iodate concentrations remained unchanged during the year at the nearby site, these concentrations changed significantly in and around the kelp forest, and were strongly related to changes in kelp canopy biomass. In particular, iodide reached its highest concentration and iodate reached its lowest concentration during the summer when the kelp canopies were near their maximum, while the opposite pattern was observed during the winter and spring when the kelp canopies were near their minimum. Further, comparisons of these changes with corresponding changes in seawater temperature and wind speed indicated that these relationships were relatively small compared to those with changes in kelp biomass. Together, our data show a strong relationship between kelp biomass and iodine metabolism.
[Mh] Termos MeSH primário: Iodo/análise
Kelp/química
Água do Mar/química
[Mh] Termos MeSH secundário: Análise de Variância
Biomassa
California
Iodatos/análise
Iodetos/análise
Estações do Ano
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Iodates); 0 (Iodides); 9679TC07X4 (Iodine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170812
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180755


  4 / 173 MEDLINE  
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[PMID]:28288186
[Au] Autor:Nelson SM; Gao YT; Nogueira LM; Shen MC; Wang B; Rashid A; Hsing AW; Koshiol J
[Ad] Endereço:Cancer Prevention Fellowship Program, Division of Cancer Prevention, National Cancer Institute, Rockville, Maryland, United States of America.
[Ti] Título:Diet and biliary tract cancer risk in Shanghai, China.
[So] Source:PLoS One;12(3):e0173935, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Trends in biliary tract cancer incidence rates have increased in Shanghai, China. These trends have coincided with economic and developmental growth, as well as a shift in dietary patterns to a more Westernized diet. To examine the effect of dietary changes on incident disease, we evaluated associations between diet and biliary tract cancers amongst men and women from a population-based case-control study in Shanghai, China. Biliary tract cancer cases were recruited from 42 collaborating hospitals in urban Shanghai, and population-based controls were randomly selected from the Shanghai Household Registry. Food frequency questionnaire data were available for 225 gallbladder, 190 extrahepatic bile duct, and 68 ampulla of Vater cancer cases. A total of 39 food groups were created and examined for associations with biliary tract cancer. Interestingly, only four food groups demonstrated a suggested association with gallbladder, extrahepatic bile duct, or ampulla of Vater cancers. The allium food group, consisting of onions, garlic, and shallots showed an inverse association with gallbladder cancer (OR: 0.81, 95% CI: 0.68-0.97). Similar trends were seen in the food group containing seaweed and kelp (OR: 0.79, 95% CI: 0.67-0.96). In contrast, both preserved vegetables and salted meats food groups showed positive associations with gallbladder cancer (OR:1.27, 95% CI: 1.06-1.52; OR: 1.18, 95% CI: 1.02-1.37, respectively). Each of these four food groups showed similar trends for extrahepatic bile duct and ampulla of Vater cancers. The results of our analysis suggest intake of foods with greater anti-inflammatory properties may play a role in decreasing the risk of biliary tract cancers. Future studies should be done to better understand effects of cultural changes on diet, and to further examine the impact diet and inflammation have on biliary tract cancer incidence.
[Mh] Termos MeSH primário: Neoplasias do Sistema Biliar/epidemiologia
Neoplasias do Sistema Biliar/etiologia
Dieta/efeitos adversos
[Mh] Termos MeSH secundário: Adulto
Idoso
Estudos de Casos e Controles
China/epidemiologia
Feminino
Neoplasias da Vesícula Biliar/epidemiologia
Neoplasias da Vesícula Biliar/etiologia
Alho
Seres Humanos
Kelp
Masculino
Meia-Idade
Cebolas
Fatores de Risco
Alga Marinha
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0173935


  5 / 173 MEDLINE  
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[PMID]:28075025
[Au] Autor:Bonaviri C; Graham M; Gianguzza P; Shears NT
[Ad] Endereço:Dipartimento di Scienze della Terra e del Mare (DiSTeM), Università di Palermo, Via Archirafi, 22, 90123, Palermo, Italy.
[Ti] Título:Warmer temperatures reduce the influence of an important keystone predator.
[So] Source:J Anim Ecol;86(3):490-500, 2017 May.
[Is] ISSN:1365-2656
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Predator-prey interactions may be strongly influenced by temperature variations in marine ecosystems. Consequently, climate change may alter the importance of predators with repercussions for ecosystem functioning and structure. In North-eastern Pacific kelp forests, the starfish Pycnopodia helianthoides is known to be an important predator of the purple sea urchin Strongylocentrotus purpuratus. Here we investigated the influence of water temperature on this predator-prey interaction by: (i) assessing the spatial distribution and temporal dynamics of both species across a temperature gradient in the northern Channel Islands, California, and (ii) investigating how the feeding rate of P. helianthoides on S. purpuratus is affected by temperature in laboratory tests. On average, at sites where mean annual temperatures were <14 °C, P. helianthoides were common, S. purpuratus was rare and kelp was persistent, whereas where mean annual temperatures exceeded 14 °C, P. helianthoides and kelp were rare and S. purpuratus abundant. Temperature was found to be the primary environmental factor influencing P. helianthoides abundance, and in turn P. helianthoides was the primary determinant of S. purpuratus abundance. In the laboratory, temperatures >16 °C (equivalent to summer temperatures at sites where P. helianthoides were rare) reduced predation rates regardless of predator and prey sizes, although larger sea urchins were consumed only by large starfishes. These results clearly demonstrate that the effect of P. helianthoides on S. purpuratus is strongly mediated by temperature, and that the local abundance and predation rate of P. helianthoides on sea urchins will likely decrease with future warming. A reduction in top-down control on sea urchins, combined with other expected impacts of climate change on kelp, poses significant risks for the persistence of kelp forests in the future.
[Mh] Termos MeSH primário: Mudança Climática
Cadeia Alimentar
Comportamento Predatório
Ouriços-do-Mar/fisiologia
Estrelas-do-Mar/fisiologia
[Mh] Termos MeSH secundário: Animais
California
Kelp
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170112
[St] Status:MEDLINE
[do] DOI:10.1111/1365-2656.12634


  6 / 173 MEDLINE  
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[PMID]:28038977
[Au] Autor:Cui C; Li Y; Liu Y; Li X; Luo S; Zhang Z; Wu R; Liang G; Sun J; Peng J; Tian P
[Ad] Endereço:National Engineering Science Research & Development Center of Algae and Sea Cucumbers of China, Provincial Key Laboratory of Genetic Improvement & Efficient Culture of Marine Algae of Shandong, Shandong Oriental Ocean Sci-tech Co. Ltd., 264003 Yantai, Shandong, PR China. Electronic address:
[Ti] Título:Determination of genetic diversity among Saccharina germplasm using ISSR and RAPD markers.
[So] Source:C R Biol;340(2):76-86, 2017 Feb.
[Is] ISSN:1768-3238
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:Various species of genus Saccharina are economically important brown macroalgae cultivated in China. The genetic background of the conserved Saccharina germplasm was not clear. In this report, DNA-based molecular markers such as inter simple sequence repeats (ISSR) and random amplified polymorphic DNA (RAPD) were used to assess the genetic diversity and phylogenetic relationships among 48 Saccharina germplasms. A total of 50 ISSR and 50 RAPD primers were tested, of which only 33 polymorphic primers (17 ISSR and 16 RAPD) had an amplified clear and reproducible profile, and could be used. Seventeen ISSR primers yielded a total of 262 bands, of which 256 were polymorphic, and 15.06 polymorphic bands per primer were amplified from 48 kelp gametophytes. Sixteen RAPD primers produced 355 bands, of which 352 were polymorphic, and 22 polymorphic bands per primer were observed across 48 individuals. The simple matching coefficient of ISSR, RAPD and pooled ISSR and RAPD dendrograms ranged from 0.568 to 0.885, 0.670 to 0.873, and 0.667 to 0.862, revealing high genetic diversity. Based on the unweighted pair group method with the arithmetic averaging algorithm (UPGMA) cluster analysis and the principal components analysis (PCA) of ISSR data, the 48 gametophytes were divided into three main groups. The Mantel test revealed a similar polymorphism distribution pattern between ISSR and RAPD markers, the correlation coefficient r was 0.62, and the results indicated that both ISSR and RAPD markers were effective to assess the selected gametophytes, while matrix correlation of the ISSR marker system (r=0.78) was better than that of the RAPD marker system (r=0.64). Genetic analysis data from this study were helpful in understanding the genetic relationships among the selected 17 kelp varieties (or lines) and provided guidance for molecular-assisted selection for parental gametophytes of hybrid kelp breeding.
[Mh] Termos MeSH primário: Variação Genética/genética
Kelp/genética
Repetições de Microssatélites/genética
Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos
[Mh] Termos MeSH secundário: Algoritmos
DNA de Algas/genética
Marcadores Genéticos
Células Germinativas Vegetais
Filogenia
Polimorfismo Genético/genética
Análise de Componente Principal
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Algal); 0 (Genetic Markers)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170314
[Lr] Data última revisão:
170314
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170101
[St] Status:MEDLINE


  7 / 173 MEDLINE  
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[PMID]:28017856
[Au] Autor:Weber XA; Edgar GJ; Banks SC; Waters JM; Fraser CI
[Ad] Endereço:Fenner School of Environment and Society, Australian National University, Building 141, Linnaeus Way, Acton ACT 2601, Australia. Electronic address: xweber@palaeome.org.
[Ti] Título:A morphological and phylogenetic investigation into divergence among sympatric Australian southern bull kelps (Durvillaea potatorum and D. amatheiae sp. nov.).
[So] Source:Mol Phylogenet Evol;107:630-643, 2017 Feb.
[Is] ISSN:1095-9513
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Genetic analyses can reveal a wealth of hitherto undiscovered cryptic biodiversity. For co-occurring and morphologically similar species, the combination of molecular, ecological and morphological analyses provides an excellent opportunity for understanding some of the processes that can lead to divergence and speciation. The Australian endemic brown macroalga Durvillaea potatorum (Phaeophyceae) was examined with a combination of genetic and morphological approaches to confirm the presence of two separate species and to infer the processes that led to their divergence. A total of 331 individuals from 11 sites around coastal Tasmania were collected and measured in situ for a range of morphological and ecological characteristics. Tissue samples were also collected for each individual to allow genetic analyses using mitochondrial (COI) and nuclear (28S) markers. Genetic analyses confirmed the presence of two deeply divergent clades. The significant morphological differentiation, despite high levels of intra-lineage variability, further supported their recognition as distinct species. We describe a new species, D. amatheiae sp. nov., which is characterised by a narrower and proportionately shorter stipe, shorter total length, and higher number of stipitate lateral blades and branches than D. potatorum (sensu stricto). The occurrence of both species in sympatry along Tasmania's eastern and western coasts, as well as their contrasting patterns of haplotype diversity, supports a hypothesis of geographical isolation, allopatric speciation and subsequent secondary contact in response to sea level and ocean current change throughout the Pleistocene glaciation cycles. This research contributes to resolving the phylogenetic relationships, taxonomy and evolution of the ecologically keystone kelp genus Durvillaea.
[Mh] Termos MeSH primário: Variação Genética
Kelp/classificação
Kelp/genética
Filogenia
Simpatria/genética
[Mh] Termos MeSH secundário: Austrália
Sequência de Bases
DNA Mitocondrial/genética
Ecossistema
Geografia
Haplótipos
Análise Multivariada
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Mitochondrial)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161227
[St] Status:MEDLINE


  8 / 173 MEDLINE  
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[PMID]:27888731
[Au] Autor:Zheng S; He M; Sui Y; Gebreluel T; Zou S; Kemuma ND; Wang C
[Ad] Endereço:Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
[Ti] Título:Kelp waste extracts combined with acetate enhances the biofuel characteristics of Chlorella sorokiniana.
[So] Source:Bioresour Technol;225:142-150, 2017 Feb.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:To probe the effect of kelp waste extracts (KWE) combined with acetate on biochemical composition of Chlorella sorokiniana, the cultures were performed under independent/combined treatment of KWE and acetate. The results showed that high cell density and biomass were obtained by KWE combined with acetate treatments, whose biomass productivity increased by 79.69-102.57% and 20.04-35.32% compared with 3.0gL acetate and KWE treatments respectively. The maximal neutral lipid per cell and lipid productivity were gained in KWE combined with 3.0gL acetate treatment, which increased by 16.32% and 129.03% compared with 3.0gL acetate, and 253.35% and 70.74% compared with KWE treatment. Meanwhile, C18:3n3 and C18:2n6c contents were reduced to 4.90% and 11.88%, whereas C16:0 and C18:1n9c were improved to 28.71% and 37.76%. Hence, supplementing appropriate acetate in KWE cultures is supposed to be a great potential method for large-scale cultivation of C. sorokiniana to generate biofuel.
[Mh] Termos MeSH primário: Acetatos/metabolismo
Biocombustíveis
Chlorella/crescimento & desenvolvimento
Chlorella/metabolismo
Resíduos Industriais
Kelp
[Mh] Termos MeSH secundário: Biomassa
Chlorella/química
Meios de Cultura/química
Metabolismo dos Lipídeos
Lipídeos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetates); 0 (Biofuels); 0 (Culture Media); 0 (Industrial Waste); 0 (Lipids)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170206
[Lr] Data última revisão:
170206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161127
[St] Status:MEDLINE


  9 / 173 MEDLINE  
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[PMID]:27878385
[Au] Autor:Hargrave MS; Foggo A; Pessarrodona A; Smale DA
[Ad] Endereço:Marine Biology and Ecology Research Centre, Plymouth University, Drake Circus, Plymouth, PL4 8AA, UK.
[Ti] Título:The effects of warming on the ecophysiology of two co-existing kelp species with contrasting distributions.
[So] Source:Oecologia;183(2):531-543, 2017 Feb.
[Is] ISSN:1432-1939
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The northeast Atlantic has warmed significantly since the early 1980s, leading to shifts in species distributions and changes in the structure and functioning of communities and ecosystems. This study investigated the effects of increased temperature on two co-existing habitat-forming kelps: Laminaria digitata, a northern boreal species, and Laminaria ochroleuca, a southern Lusitanian species, to shed light on mechanisms underpinning responses of trailing and leading edge populations to warming. Kelp sporophytes collected from southwest United Kingdom were maintained under 3 treatments: ambient temperature (12 °C), +3 °C (15 °C) and +6 °C (18 °C) for 16 days. At higher temperatures, L. digitata showed a decline in growth rates and Fv/Fm, an increase in chemical defence production and a decrease in palatability. In contrast, L. ochroleuca demonstrated superior growth and photosynthesis at temperatures higher than current ambient levels, and was more heavily grazed. Whilst the observed decreased palatability of L. digitata held at higher temperatures could reduce top-down pressure on marginal populations, field observations of grazer densities suggest that this may be unimportant within the study system. Overall, our study suggests that shifts in trailing edge populations will be primarily driven by ecophysiological responses to high temperatures experienced during current and predicted thermal maxima, and although compensatory mechanisms may reduce top-down pressure on marginal populations, this is unlikely to be important within the current biogeographical context. Better understanding of the mechanisms underpinning climate-driven range shifts is important for habitat-forming species like kelps, which provide organic matter, create biogenic structure and alter environmental conditions for associated communities.
[Mh] Termos MeSH primário: Kelp
Fotossíntese
[Mh] Termos MeSH secundário: Ecossistema
Laminaria
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161124
[St] Status:MEDLINE
[do] DOI:10.1007/s00442-016-3776-1


  10 / 173 MEDLINE  
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[PMID]:27392308
[Au] Autor:Provost EJ; Kelaher BP; Dworjanyn SA; Russell BD; Connell SD; Ghedini G; Gillanders BM; Figueira W; Coleman MA
[Ad] Endereço:National Marine Science Centre & Centre for Coastal Biogeochemistry Research, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, NSW, Australia.
[Ti] Título:Climate-driven disparities among ecological interactions threaten kelp forest persistence.
[So] Source:Glob Chang Biol;23(1):353-361, 2017 Jan.
[Is] ISSN:1365-2486
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The combination of ocean warming and acidification brings an uncertain future to kelp forests that occupy the warmest parts of their range. These forests are not only subject to the direct negative effects of ocean climate change, but also to a combination of unknown indirect effects associated with changing ecological landscapes. Here, we used mesocosm experiments to test the direct effects of ocean warming and acidification on kelp biomass and photosynthetic health, as well as climate-driven disparities in indirect effects involving key consumers (urchins and rock lobsters) and competitors (algal turf). Elevated water temperature directly reduced kelp biomass, while their turf-forming competitors expanded in response to ocean acidification and declining kelp canopy. Elevated temperatures also increased growth of urchins and, concurrently, the rate at which they thinned kelp canopy. Rock lobsters, which are renowned for keeping urchin populations in check, indirectly intensified negative pressures on kelp by reducing their consumption of urchins in response to elevated temperature. Overall, these results suggest that kelp forests situated towards the low-latitude margins of their distribution will need to adapt to ocean warming in order to persist in the future. What is less certain is how such adaptation in kelps can occur in the face of intensifying consumptive (via ocean warming) and competitive (via ocean acidification) pressures that affect key ecological interactions associated with their persistence. If such indirect effects counter adaptation to changing climate, they may erode the stability of kelp forests and increase the probability of regime shifts from complex habitat-forming species to more simple habitats dominated by algal turfs.
[Mh] Termos MeSH primário: Mudança Climática
Cadeia Alimentar
Kelp/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Animais
Biomassa
Clima
Ecossistema
Florestas
Nephropidae
Ouriços-do-Mar
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160709
[St] Status:MEDLINE
[do] DOI:10.1111/gcb.13414



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