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1.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33972407

RESUMO

Ocean warming and acidification threaten the future growth of coral reefs. This is because the calcifying coral reef taxa that construct the calcium carbonate frameworks and cement the reef together are highly sensitive to ocean warming and acidification. However, the global-scale effects of ocean warming and acidification on rates of coral reef net carbonate production remain poorly constrained despite a wealth of studies assessing their effects on the calcification of individual organisms. Here, we present global estimates of projected future changes in coral reef net carbonate production under ocean warming and acidification. We apply a meta-analysis of responses of coral reef taxa calcification and bioerosion rates to predicted changes in coral cover driven by climate change to estimate the net carbonate production rates of 183 reefs worldwide by 2050 and 2100. We forecast mean global reef net carbonate production under representative concentration pathways (RCP) 2.6, 4.5, and 8.5 will decline by 76, 149, and 156%, respectively, by 2100. While 63% of reefs are projected to continue to accrete by 2100 under RCP2.6, 94% will be eroding by 2050 under RCP8.5, and no reefs will continue to accrete at rates matching projected sea level rise under RCP4.5 or 8.5 by 2100. Projected reduced coral cover due to bleaching events predominately drives these declines rather than the direct physiological impacts of ocean warming and acidification on calcification or bioerosion. Presently degraded reefs were also more sensitive in our analysis. These findings highlight the low likelihood that the world's coral reefs will maintain their functional roles without near-term stabilization of atmospheric CO2 emissions.


Assuntos
Antozoários/fisiologia , Carbonato de Cálcio/metabolismo , Mudança Climática , Recifes de Corais , Animais , Antozoários/química , Carbonato de Cálcio/química , Humanos , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar/química
2.
Nature ; 543(7645): 373-377, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28300113

RESUMO

During 2015-2016, record temperatures triggered a pan-tropical episode of coral bleaching, the third global-scale event since mass bleaching was first documented in the 1980s. Here we examine how and why the severity of recurrent major bleaching events has varied at multiple scales, using aerial and underwater surveys of Australian reefs combined with satellite-derived sea surface temperatures. The distinctive geographic footprints of recurrent bleaching on the Great Barrier Reef in 1998, 2002 and 2016 were determined by the spatial pattern of sea temperatures in each year. Water quality and fishing pressure had minimal effect on the unprecedented bleaching in 2016, suggesting that local protection of reefs affords little or no resistance to extreme heat. Similarly, past exposure to bleaching in 1998 and 2002 did not lessen the severity of bleaching in 2016. Consequently, immediate global action to curb future warming is essential to secure a future for coral reefs.


Assuntos
Antozoários/metabolismo , Recifes de Corais , Aquecimento Global/estatística & dados numéricos , Animais , Austrália , Clorofila/metabolismo , Clorofila A , Conservação dos Recursos Naturais/tendências , Aquecimento Global/prevenção & controle , Água do Mar/análise , Temperatura
3.
Clin J Oncol Nurs ; 25(5): 539-545, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34533507

RESUMO

BACKGROUND: Pain and nausea affect a significant number of patients with cancer. Applying foot reflexology to this population has had some positive effects, but more studies are needed to confirm its efficacy. OBJECTIVES: The purpose of this study was to conduct a randomized controlled trial to evaluate the effects of foot reflexology on pain and nausea among inpatients with cancer as compared to traditional nursing care alone. METHODS: A pilot study was conducted with adult patients with cancer hospitalized on a 24-bed inpatient oncology unit. Using convenience sampling, 40 patients provided consent and were randomized into either the intervention or control group. Each group had a treatment session of 20-25 minutes in which pre- and postsession surveys were completed, with reflexology performed in the intervention group only. FINDINGS: Results show that foot reflexology significantly decreases pain for inpatients with cancer as compared to traditional nursing care alone. Although the effects on nausea are not statistically significant, they may be clinically relevant; the mean changes in pre- and postsession nausea ratings indicate at least some decreased nausea among patients in the intervention group.


Assuntos
Manipulações Musculoesqueléticas , Neoplasias , Adulto , Humanos , Pacientes Internados , Massagem , Náusea/etiologia , Náusea/terapia , Neoplasias/complicações , Neoplasias/terapia , Dor , Projetos Piloto
4.
Science ; 359(6371): 80-83, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29302011

RESUMO

Tropical reef systems are transitioning to a new era in which the interval between recurrent bouts of coral bleaching is too short for a full recovery of mature assemblages. We analyzed bleaching records at 100 globally distributed reef locations from 1980 to 2016. The median return time between pairs of severe bleaching events has diminished steadily since 1980 and is now only 6 years. As global warming has progressed, tropical sea surface temperatures are warmer now during current La Niña conditions than they were during El Niño events three decades ago. Consequently, as we transition to the Anthropocene, coral bleaching is occurring more frequently in all El Niño-Southern Oscillation phases, increasing the likelihood of annual bleaching in the coming decades.


Assuntos
Antozoários , Recifes de Corais , El Niño Oscilação Sul , Aquecimento Global , Animais , Água do Mar
5.
Sci Rep ; 7(1): 2920, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592825

RESUMO

Coral growth is an important component of reef health and resilience. However, few studies have investigated temporal and/or spatial variation in growth of branching corals, which are important contributors to the structure and function of reef habitats. This study assessed growth (linear extension, density, and calcification) of three branching coral species (Acropora muricata, Pocillopora damicornis and Isopora palifera) at three distinct locations (Lizard Island, Davies/Trunk Reef, and Heron Island) along Australia's Great Barrier Reef (GBR). Annual growth rates of all species were highest at Lizard Island and declined with increasing latitude, corresponding with differences in temperature. Within locations, however, seasonal variation in growth did not directly correlate with temperature. Between October 2012 and October 2014, the highest growth of A. muricata was in the 2013-14 summer at Lizard Island, which was unusually cool and ~0.5 °C less than the long-term summer average temperature. At locations where temperatures reached or exceeded the long-term summer maxima, coral growth during summer periods was equal to, if not lower than, winter periods. This study shows that temperature has a significant influence on spatiotemporal patterns of branching coral growth, and high summer temperatures in the northern GBR may already be constraining coral growth and reef resilience.


Assuntos
Antozoários/crescimento & desenvolvimento , Recifes de Corais , Ecossistema , Animais , Austrália , Calcificação Fisiológica , Meio Ambiente , Geografia , Densidade Demográfica , Análise Espaço-Temporal
7.
Sci Data ; 3: 160017, 2016 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-27023900

RESUMO

Trait-based approaches advance ecological and evolutionary research because traits provide a strong link to an organism's function and fitness. Trait-based research might lead to a deeper understanding of the functions of, and services provided by, ecosystems, thereby improving management, which is vital in the current era of rapid environmental change. Coral reef scientists have long collected trait data for corals; however, these are difficult to access and often under-utilized in addressing large-scale questions. We present the Coral Trait Database initiative that aims to bring together physiological, morphological, ecological, phylogenetic and biogeographic trait information into a single repository. The database houses species- and individual-level data from published field and experimental studies alongside contextual data that provide important framing for analyses. In this data descriptor, we release data for 56 traits for 1547 species, and present a collaborative platform on which other trait data are being actively federated. Our overall goal is for the Coral Trait Database to become an open-source, community-led data clearinghouse that accelerates coral reef research.


Assuntos
Antozoários , Bases de Dados Factuais , Animais , Recifes de Corais , Ecossistema , Oceanos e Mares , Filogenia
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