Deaths by tuberculosis in a priority city for disease control in the Brazilian Northeast: sociodemographic-operational characteristics and vulnerable territories.

Introduction: Incorporating spatial approaches into epidemiological research is a challenge in public health research. The goal in this study was to analyze the spatial distribution of cases of deaths by tuberculosis in Imperatriz – MA (Brazil) and to characterize these events according to sociodemographic and operational characteristics. Methods: In this ecological study, all deaths from tuberculosis as the primary cause registered in the Mortality Information System from 2005 to 2014 were considered. The research variables were subject to descriptive analysis, point density analysis (Kernel Intensity Estimation) and area analysis. Results: Fifty cases of deaths by TB were identified, particularly the pulmonary clinical form. Male patients were predominant, with a median age of 59 years, mulatto race/color, single, who had finished secondary education. Most deaths happened at the hospital, with medical care before death and without autopsy. Most events happened at the hospital, with medical care delivery by an assistant physician and without autopsy. The point density revealed heterogeneity in the spatial distribution of the deaths, with rates of up to 2.33 deaths/km2. The area analysis by census sector presented age standardized mortality rates of 0.00 to 4.00 deaths/100,000 inhabitants-year. Conclusion: The results contributed to the knowledge on the spatial distribution of cases of deaths by Tuberculosis and their characteristics in the research scenario. The importance of space is highlighted as a methodological alternative to support the planning, monitoring and assessment of health actions, targeting interventions to the control of the disease in vulnerable territories. Keywords: Tuberculosis; Health Information Systems; Mortality; Spatial analysis

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia

Spatial distribution and temporal trend of tuberculosis and its social determinants in a hyper-endemic municipality in northeastern Brazil: A hybrid study of spatial analysis and time series

Introdução: A tuberculose, doença fortemente ligada às desigualdades sociais e privações de oportunidades, representa um grave problema de saúde pública, apesar dos esforços para prevenir o seu avanço. Superá-la implica uma visão acurada das condições de vida, dos modos de produção e reprodução social nos territórios, bem como dos determinantes sociais. Objetivo: O estudo teve como objetivo analisar a distribuição espacial da TB, sua relação com os determinantes sociais da saúde e a tendência temporal da doença. Métodos: Trata-se de um estudo ecológico que teve uma etapa de abordagem espacial e outra, de séries temporais. Foram selecionados casos de tuberculose diagnosticados entre 2002 e 2018, registrados no Sistema de Informações de Agravos de Notificação e coletados junto ao Serviço de Vigilância em Saúde da Unidade Gestora Regional de Saúde do governo do Estado do Maranhão, entre os meses de Janeiro e Fevereiro de 2019. As variáveis usadas foram: gênero, grupo etário, entrada para tratamento, encerramento, ano de notificação, endereço residencial, renda familiar, moradores por domicílio, acesso dos residentes aos serviços de infraestrutura urbana. Na análise espacial procedeu-se a identificação das áreas de maior ocorrência da doença e dos desfechos óbito, cura e abandono, recorrendo-se à estatística de varredura. Também foi testada associação da ocorrência de tuberculose com os determinantes sociais, utilizando-se dos modelos aditivos generalizados para localização, escala e forma. Nas análises de séries temporais, aplicou-se o método de decomposição Seasonal Trend Decomposition using Loess. Recorreu-se nessa etapa aos modelos auto-regressivos integrados de médias móveis e o método de Box e Jenkins, para escolher àqueles mais adequados. Resultados: Foram identificados 1.620 casos de tuberculose, o que representou uma detecção de 39,2 casos para cada 100 mil habitantes, com incidência de 49,7 casos em homens e 34,0 casos em mulheres. No grupo etário entre 15 até 59 anos de idade, incidência de 57,0 casos para homens e 34,4 casos para as mulheres. Foi possível identificar um aglomerado de risco estatisticamente significativo para a doença. O estudo identificou a baixa renda como o determinante social associado aos casos de TB. Quanto às tendências da série temporal, embora fosse observada uma tendência de declínio na incidência geral dos casos de tuberculose, nas mulheres, observou-se um aumento. Conclusão: A região central urbana da cidade apresentou maior aglomerado de casos de TB, área com alta densidade demográfica e precárias condições sanitárias e socioeconômicas. Foi possível observar associação entre os determinantes sociais e a ocorrência de TB. A pesquisa evidenciou decréscimo da doença no cenário sob estudo, todavia num compasso aquém das expectativas da OMS.Background: Tuberculosis, a disease strongly linked to social inequality and deprivation of opportunities, represents a serious public health problem, despite efforts to prevent its progress. Overcoming it implies an accurate view of the living conditions, the modes of production and social reproduction in the territories, as well as the social determinants. Aim: The study aimed to analyze the spatial distribution of TB, its relationship with the social determinants of health and the temporal trend of the disease. Methods: This is an ecological study that had a stage of spatial approach and another, of time series. Tuberculosis cases diagnosed between 2002 and 2018 were selected, registered in the Information System for Notifiable Diseases and collected with the Health Surveillance Service of the Regional Health Management Unit of the Maranhão State government, between the months of January and February of 2019. The variables used were: gender, age group, entry to treatment, closure, year of notification, home address, family income, residents per household, residents\' access to urban infrastructure services. In the spatial analysis, the areas with the highest occurrence of the disease and the outcomes of death, cure and abandonment were identified, using scanning statistics. An association between the occurrence of tuberculosis and social determinants was also tested, using generalized additive models for location, scale and shape. In the analysis of time series, the Seasonal Trend Decomposition using Loess decomposition method was applied. In this stage, we used the integrated autoregressive models of moving averages and the method of Box and Jenkins, to choose the most suitable ones. Results: 1,620 cases of tuberculosis were identified, which represented a detection of 39.2 cases for every 100 thousand inhabitants, with an incidence of 49.7 cases in men and 34.0 cases in women. In the age group between 15 and 59 years of age, incidence of 57.0 cases for men and 34.4 cases for women. It was possible to identify a cluster of statistically significant risk for the disease. The study identified low income as the social determinant associated with TB cases. Regarding trends in the time series, although there was a tendency to decline in the overall incidence of tuberculosis cases in women, an increase was observed. Conclusion: The central urban region of the city presented a greater cluster of TB cases, an area with high demographic density and poor sanitary and socioeconomic conditions. It was possible to observe an association between social determinants and the occurrence of TB. The research showed a decrease of the disease in the scenario under study, however at a pace below the expectations of WH

Perception of the family health strategy professionals in a health district of natal-rn About dot 2009

Objective: To describe the perception of health professionals from the Family Health Strategy (FHS) of Natal West Sanitary District about Directly Observed Therapy (DOT) under the viewpoint of the active search for respiratory symptoms and Direct Observation (DO). Methods: It is a descriptive exploratory study with a quantitative approach involving health professionals from the FHS in Natal-RN. Results: All nurses and physicians, as well as 84% of Community Health Workers and 75% of nursing assistants/technicians acknowledge DOT and work in tuberculosis control. The answers were grouped and classified according to similarity which resulted in a theme and two subthemes that represent the viewpoint of the professionals about DOT. Conclusion: Most of the FHS professionals from Natal Western District summarize DOT as direct observation, diagnosis of respiratory symptoms, and medication administration.Objetivo: Descrever a percepção dos profissionais de saúde da Estratégia de Saúde da Família (ESF) do Distrito Sanitário Oeste, Natal-RN, quanto ao Tratamento Supervisionado Diretamente Observado (DOTS) na ótica da busca ativa dos sintomáticos respiratórios e do Tratamento Supervisionado (TS). Métodos: Estudo descritivo-exploratório com abordagem quantitativa que envolveu profissionais da saúde da ESF, na cidade de Natal-RN. Resultados: todos os enfermeiros e médicos, assim como 84% dos ACS e 75% dos auxiliares/ técnicos de enfermagem indicaram que conhecem o DOTS e trabalham no controle da TB. Suas respostas foram agrupadas e classificadas segundo a semelhança, surgindo assim uma temática e duas subtemáticas que representam o entendimento dos profissionais sobre o DOTS. Conclusão: Pode-se concluir que a maioria dos profissionais de saúde da ESF do Distrito Oeste da cidade de Natal/ RN entende que a estratégia DOTS se resume à supervisão do TS, diagnóstico dos sintomáticos respiratórios e administração de medicamentos.Objetivo: Describir la percepción de los profesionales de la salud de la Estrategia de Salud de la Familia (ESF) del Distrito Sanitario Oeste, Natal-RN, en lo que concierne al Tratamiento Supervisado Directamente Observado (DOTS) desde la óptica de la busca activa de los sintomáticos respiratorios y del Tratamiento Supervisado (TS). Métodos: estudio descriptivo-exploratorio cuantitativo que reunió profesionales de la salud de la ESF, en la ciudad de Natal-RN. Resultados: Todos los enfermeros y médicos, así como 84% de los ACS y 75% de los auxiliares/ técnicos de enfermería indicaron que conocen el DOTS y trabajan en el control de la TB. Sus respuestas han sido agrupadas y clasificadas según semejanza, surgiendo una temática y dos sub-temáticas que representan el entendimiento de los profesionales sobre el DOTS. Conclusión: Se puede concluir que la mayoría de los profesionales de salud de la ESF del Distrito Oeste de la ciudad de Natal/ RN entienden que la estrategia DOTS se resume a la supervisión del TS, diagnóstico de los sintomáticos respiratorios y administración de medicamentos

Consistent patterns of common species across tropical tree communities

International audienceAbstract Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations 1–6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories 7 , we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1–6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees

Consistent patterns of common species across tropical tree communities

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories , we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees

Consistent patterns of common species across tropical tree communities

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories , we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees