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1.
Nat Commun ; 15(1): 549, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263406

RESUMO

Temperature is a fundamental driver of species distribution and ecosystem functioning. Yet, our knowledge of the microclimatic conditions experienced by organisms inside tropical forests remains limited. This is because ecological studies often rely on coarse-gridded temperature estimates representing the conditions at 2 m height in an open-air environment (i.e., macroclimate). In this study, we present a high-resolution pantropical estimate of near-ground (15 cm above the surface) temperatures inside forests. We quantify diurnal and seasonal variability, thus revealing both spatial and temporal microclimate patterns. We find that on average, understory near-ground temperatures are 1.6 °C cooler than the open-air temperatures. The diurnal temperature range is on average 1.7 °C lower inside the forests, in comparison to open-air conditions. More importantly, we demonstrate a substantial spatial variability in the microclimate characteristics of tropical forests. This variability is regulated by a combination of large-scale climate conditions, vegetation structure and topography, and hence could not be captured by existing macroclimate grids. Our results thus contribute to quantifying the actual thermal ranges experienced by organisms inside tropical forests and provide new insights into how these limits may be affected by climate change and ecosystem disturbances.


Assuntos
Ecossistema , Florestas , Temperatura , Mudança Climática , Sistemas Computacionais
2.
Nat Commun ; 14(1): 8129, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097604

RESUMO

Habitat fragmentation could potentially affect tree architecture and allometry. Here, we use ground surveys of terrestrial LiDAR in Central Amazonia to explore the influence of forest edge effects on tree architecture and allometry, as well as forest biomass, 40 years after fragmentation. We find that young trees colonising the forest fragments have thicker branches and architectural traits that optimise for light capture, which result in 50% more woody volume than their counterparts of similar stem size and height in the forest interior. However, we observe a disproportionately lower height in some large trees, leading to a 30% decline in their woody volume. Despite the substantial wood production of colonising trees, the lower height of some large trees has resulted in a net loss of 6.0 Mg ha-1 of aboveground biomass - representing 2.3% of the aboveground biomass of edge forests. Our findings indicate a strong influence of edge effects on tree architecture and allometry, and uncover an overlooked factor that likely exacerbates carbon losses in fragmented forests.


Assuntos
Florestas , Árvores , Biomassa , Ecossistema , Madeira , Clima Tropical
3.
Sci Total Environ ; 867: 161320, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603629

RESUMO

Savannas contribute to ca. 30 % of the total terrestrial net primary productivity and are responsible for significant carbon storage. Savannas in South America are mostly found within the Cerrado Domain, which is very threatened and presents remarkable carbon pools. Herein, we used a unique dataset of 21 Cerrado sites spanning 144 permanent field plots in Southeastern Brazil to assess the general patterns of above and belowground carbon stocks. We identified the main environmental and tree diversity drivers of aboveground wood carbon and productivity, belowground carbon stocks (roots and soil), carbon ratios (root:shoot and above:below) and total carbon stocks in the Cerrado through a combination of climatic estimates, fire frequency data, field measurements of vegetation, roots, soil carbon, nutrients and texture, and assessment of different components of diversity (species, functional and phylogenetic). Our findings reveal average aboveground, root, and soil carbon stocks of 20.4, 14.24, and 123.13 Mg.ha-1, respectively. Average Root:Shoot and Above:Below confirm the "inverted forest" concept with values of 1.58 and 0.21, respectively. Total carbon was 145.62 Mg.ha-1, reinforcing the great amount of carbon storage in the Cerrado and its role in the carbon cycle and dynamics. Tree diversity variables (mainly species diversity and functional composition variables) had more significant effects over aboveground variables, whereas environmental variables had more significant effects over belowground variables. Ratios and total carbon mixed up these effects. The impressive values of carbon storage, especially belowground, point out the need to better manage and protect the Cerrado. Moreover, our findings might be particularly relevant for discussions on restoration programs focused on the trees-for­carbon idea that do not consider species diversity and belowground carbon stocks.


Assuntos
Carbono , Pradaria , Carbono/análise , Brasil , Filogenia , Florestas , Solo , Ecossistema , Biomassa
4.
Nat Commun ; 13(1): 917, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177619

RESUMO

Predictions of the magnitude and timing of leaf phenology in Amazonian forests remain highly controversial. Here, we use terrestrial LiDAR surveys every two weeks spanning wet and dry seasons in Central Amazonia to show that plant phenology varies strongly across vertical strata in old-growth forests, but is sensitive to disturbances arising from forest fragmentation. In combination with continuous microclimate measurements, we find that when maximum daily temperatures reached 35 °C in the latter part of the dry season, the upper canopy of large trees in undisturbed forests lost plant material. In contrast, the understory greened up with increased light availability driven by the upper canopy loss, alongside increases in solar radiation, even during periods of drier soil and atmospheric conditions. However, persistently high temperatures in forest edges exacerbated the upper canopy losses of large trees throughout the dry season, whereas the understory in these light-rich environments was less dependent on the altered upper canopy structure. Our findings reveal a strong influence of edge effects on phenological controls in wet forests of Central Amazonia.


Assuntos
Florestas , Folhas de Planta/fisiologia , Árvores/fisiologia , Brasil , Luz , Microclima , Estações do Ano , Solo/química , Água/química
5.
Rev. ABENO ; 21(1): 1639, dez. 2021. tab, ilus
Artigo em Português | BBO - Odontologia | ID: biblio-1373360

RESUMO

Este estudo visa analisar a relevância dosEstágios Supervisionados em Odontologia no Sistema único de Saúde para o ensino, serviço e comunidade. Trata-se deuma revisão de literatura integrativacombusca nas bases de dadosBVS/LILACS, SciELO e Google Acadêmico. Os estudos para análise foram escolhidos após o estabelecimento de critérios de inclusão(artigos publicados nos últimos 5 anosque tratem das percepções dos envolvidos nessa vivência de integração,autores clássicos, teses, relatos de experiência, artigos em português, inglês e espanhol)e exclusão(artigos semDOIoutratando deestágiosem outras áreasesistemas de saúde). Assim, após a busca inicial, foram selecionados 113 estudosno total sendo 25, 8e 100,respectivamente,da BVS/LILACS, SciELO e Google Acadêmico. No entanto, após a leitura dos artigos na íntegra somente 17publicaçõesforam selecionadas. Dessa forma, das competênciasgerais apresentadas pelas Diretrizes Curriculares Nacionais em Odontologia, os estudos indicam que trabalho em equipe, atenção integral à saúde do usuário e comunicação adequada com usuários e membros da equipe são as características mais estimuladasna formação dos estudantes. Ademais, destaca-se a atenção primária como principal cenário de atuação do estagiário, compouco enfoque nos demais níveis de atenção. Analisou-se que perante as fragilidades desse processo, o estudante, sob orientação da preceptoria, deve adaptar-se àrealidade vivenciada para exercer a sua função com sucesso. Logo, o estágio insere o estudante na realidade profissional,além de trabalhar as suas insegurançase a capacidade de adaptação (AU).


This study aims to analyze the relevance of Supervised Internships in Dentistry at SUS for teaching, serviceand community. This is an integrative literature review, which was elaborated through a search in the databases: BVS/LILACS, SCIELO and GOOGLE ACADEMIC. The studies for analysis were chosen after the establishment of inclusion criteria: articles publishedin the last 5 years dealing with the perceptions of those involved in this integration experience, classical authors, theses, experience reports, articles in Portuguese, English and Spanish; and exclusion: articles without DOI and dealing with internshipsin other areas and health systems. Thus, after reading the titles, 113 studies were selected in total, 25, 8 and 100 respectively from the BVS/LILACS, SCIELO and Google academic. However, after reading the articles in full, only 17 publications were selected. Thus, from the general characteristics presented by the National Curriculum Guidelines in dentistry, studies indicate that teamwork, comprehensive care to the user's health and adequate communication with users and team members are the characteristicsmost encouraged by academics. Furthermore, primary care is highlighted as the main scenario in which the intern works, with little focus on other levels of care. It was analyzed that, in view of the weaknesses of this process, the student, under the guidance of the preceptorship, must adapt to the reality experienced in order to successfully perform his role. Therefore, the internship inserts the student into the professional reality, in addition to working on their insecurities and adaptability (AU).


Assuntos
Atenção Primária à Saúde , Sistema Único de Saúde , Estágio Clínico , Assistência Integral à Saúde , Currículo , Preceptoria , Relações Interpessoais
6.
Nat Commun ; 12(1): 1526, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750781

RESUMO

The past 40 years in Southeast Asia have seen about 50% of lowland rainforests converted to oil palm and other plantations, and much of the remaining forest heavily logged. Little is known about how fragmentation influences recovery and whether climate change will hamper restoration. Here, we use repeat airborne LiDAR surveys spanning the hot and dry 2015-16 El Niño Southern Oscillation event to measure canopy height growth across 3,300 ha of regenerating tropical forests spanning a logging intensity gradient in Malaysian Borneo. We show that the drought led to increased leaf shedding and branch fall. Short forest, regenerating after heavy logging, continued to grow despite higher evaporative demand, except when it was located close to oil palm plantations. Edge effects from the plantations extended over 300 metres into the forests. Forest growth on hilltops and slopes was particularly impacted by the combination of fragmentation and drought, but even riparian forests located within 40 m of oil palm plantations lost canopy height during the drought. Our results suggest that small patches of logged forest within plantation landscapes will be slow to recover, particularly as ENSO events are becoming more frequent.


Assuntos
El Niño Oscilação Sul/efeitos adversos , Florestas , Árvores , Clima Tropical , Arecaceae , Sudeste Asiático , Bornéu , Mudança Climática , Secas , Ecologia , Humanos , Malásia , Folhas de Planta , Floresta Úmida
7.
Conserv Lett ; 11(5): e12564, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31031821

RESUMO

Conservation policy decisions can suffer from a lack of evidence, hindering effective decision-making. In nature conservation, studies investigating why policy is often not evidence-informed have tended to focus on Western democracies, with relatively small samples. To understand global variation and challenges better, we established a global survey aimed at identifying top barriers and solutions to the use of conservation science in policy. This obtained the views of 758 people in policy, practice, and research positions from 68 countries across six languages. Here we show that, contrary to popular belief, there is agreement between groups about how to incorporate conservation science into policy, and there is thus room for optimism. Barriers related to the low priority of conservation were considered to be important, while mainstreaming conservation was proposed as a key solution. Therefore, priorities should focus on convincing the public of the importance of conservation as an issue, which will then influence policy-makers to adopt pro-environmental long-term policies.

8.
PLoS One ; 11(5): e0154738, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27187074

RESUMO

Tree stem form in native tropical forests is very irregular, posing a challenge to establishing taper equations that can accurately predict the diameter at any height along the stem and subsequently merchantable volume. Artificial intelligence approaches can be useful techniques in minimizing estimation errors within complex variations of vegetation. We evaluated the performance of Random Forest® regression tree and Artificial Neural Network procedures in modelling stem taper. Diameters and volume outside bark were compared to a traditional taper-based equation across a tropical Brazilian savanna, a seasonal semi-deciduous forest and a rainforest. Neural network models were found to be more accurate than the traditional taper equation. Random forest showed trends in the residuals from the diameter prediction and provided the least precise and accurate estimations for all forest types. This study provides insights into the superiority of a neural network, which provided advantages regarding the handling of local effects.


Assuntos
Inteligência Artificial , Ecossistema , Modelos Teóricos , Árvores , Algoritmos , Brasil , Florestas , Geografia , Redes Neurais de Computação , Árvores/crescimento & desenvolvimento
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