46 research outputs found

    Evidence of increasing drought severity caused by temperature rise in southern Europe

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    We use high quality climate data from ground meteorological stations in the Iberian Peninsula (IP) and robust drought indices to confirm that drought severity has increased in the past five decades, as a consequence of greater atmospheric evaporative demand resulting from temperature rise. Increased drought severity is independent of the model used to quantify the reference evapotranspiration. We have also focused on drought impacts to droughtsensitive systems, such as river discharge, by analyzing streamflow data for 287 rivers in the IP, and found that hydrological drought frequency and severity have also increased in the past five decades in natural, regulated and highly regulated basins. Recent positive trend in the atmospheric water demand has had a direct influence on the temporal evolution of streamflows, clearly identified during the warm season, in which higher evapotranspiration rates are recorded. This pattern of increase in evaporative demand and greater drought severity is probably applicable to other semiarid regions of the world, including other Mediterranean areas, the Sahel, southern Australia and South Africa, and can be expected to increasingly compromise water supplies and cause political, social and economic tensions among regions in the near future.This work has been supported by research projects CGL201127574CO202, CGL201127536 and CGL2011–24185 financed by the Spanish Commission of Science and Technology and FEDER, ‘Demonstration and validation of innovative methodology for regional climate change adaptation in the Mediterranean area (LIFE MEDACC)’ financed by the LIFE programme of the European Commission, CTTP1/12, financed by the Comunidad de Trabajo de los Pirineos, and QSECA (PTDC/AAGGLO/ 4155/2012) funded by the Portuguese Foundation for Science and Technology (FCT). ASL was supported by a postdoctoral fellowship from the Catalan Government (2011 BPB 00078) and CAM was supported by a Juan de la Cierva fellowship by the Spanish Government

    Tree mode of death and mortality risk factors across Amazon forests

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    The carbon sink capacity of tropical forests is substantially affected by tree mortality. However, the main drivers of tropical tree death remain largely unknown. Here we present a pan-Amazonian assessment of how and why trees die, analysing over 120,000 trees representing > 3800 species from 189 long-term RAINFOR forest plots. While tree mortality rates vary greatly Amazon-wide, on average trees are as likely to die standing as they are broken or uprooted—modes of death with different ecological consequences. Species-level growth rate is the single most important predictor of tree death in Amazonia, with faster-growing species being at higher risk. Within species, however, the slowest-growing trees are at greatest risk while the effect of tree size varies across the basin. In the driest Amazonian region species-level bioclimatic distributional patterns also predict the risk of death, suggesting that these forests are experiencing climatic conditions beyond their adaptative limits. These results provide not only a holistic pan-Amazonian picture of tree death but large-scale evidence for the overarching importance of the growth–survival trade-off in driving tropical tree mortality

    Tree mode of death and mortality risk factors across Amazon forests

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    The carbon sink capacity of tropical forests is substantially affected by tree mortality. However, the main drivers of tropical tree death remain largely unknown. Here we present a pan-Amazonian assessment of how and why trees die, analysing over 120,000 trees representing > 3800 species from 189 long-term RAINFOR forest plots. While tree mortality rates vary greatly Amazon-wide, on average trees are as likely to die standing as they are broken or uprooted—modes of death with different ecological consequences. Species-level growth rate is the single most important predictor of tree death in Amazonia, with faster-growing species being at higher risk. Within species, however, the slowest-growing trees are at greatest risk while the effect of tree size varies across the basin. In the driest Amazonian region species-level bioclimatic distributional patterns also predict the risk of death, suggesting that these forests are experiencing climatic conditions beyond their adaptative limits. These results provide not only a holistic pan-Amazonian picture of tree death but large-scale evidence for the overarching importance of the growth–survival trade-off in driving tropical tree mortality

    Anales de EdafologĂ­a y AgrobiologĂ­a Tomo 47 NĂșmero 3-4

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    Suelos. FĂ­sica. Resistencia del suelo y susceptibilidad a la compactaciĂłn en terrenos a monte sometidos a pastoreo. Por R. PĂ©rez Moreira y F. Diaz-Fierros Viqueira.-- La reserva de agua Ăștil de los suelos de Galicia. l. RelaciĂłn con la textura y el contenido de materia orgĂĄnica. Por A. M. Martinez Cortizas.-- QuĂ­mica Empleo de aminas alifĂĄticas en el estudio de asociaciones haloisita-esmectita en suelos. Por F. J. Aragoneses, J. Casas, y J. L. Martin de Vidales.-- QuelaciĂłn por EDDHA de micronutrientes en suelos calizos. EcuaciĂłn de lĂ­mite mĂĄximo. Por M. JuĂĄrez, J. SĂĄnchez-AndrĂ©u, L. Pla y J. Jorda.-- QuelaciĂłn por EDDHA de micronutrientes en suelos calizos. EcuaciĂłn de orden "n ".Por J. SĂĄnchez-AndrĂ©u, M. Juarez, L. Pla y J. JordĂĄ.-- GĂ©nesis, ClasificaciĂłn y CartografĂ­a CaracterizaciĂłn de un podsol ferro - hĂșmico en el Puerto de la Quesera (Sierra del AyllĂłn). Por R. Espejo Serrano, F. Guerrero LĂłpez y A. Saa Requejo.-- Natrixerales en el Baix Segre (Lleida). Por J. Bech i BorrĂĄs, J. Garrigo i Reixach y J. R. Torrento i Marselles.-- Aspectos micromorfolĂłgicos del horizonte superior en suelos artificiales (Sorribas) de las Islas Canarias. Por A. RodrĂ­guez RodrĂ­guez y J. M. Ontañón SĂĄnchez.-- Fertilidad Influencia de diferentes factores del suelo sobre su contenido en microelementos asimilables: Mn, Fe, Cu y Zn. Por B. C. Ortega, Ma C. Ortega y J. G. de las Heras.--Incidencia de la salinidad del agua de riego en la mineralizaciĂłn del nitrĂłgeno orgĂĄnico en suelos calizos del sureste español. Por J. GarcĂ­a-Serna, J. SĂĄnchez AndrĂ©u, M. JuĂĄrez y J. Mataix.-- BiologĂ­a Vegetal-FisiologĂ­a Efectos de la toxicidad del flĂșor sobre el ciclo biolĂłgico en especies herbĂĄceas dicotiledoneas. Por M. Ibarra, F. LĂłpez Belmonte y Ma A. Diez.-- Efectos de la toxicidad del flĂșor sobre el ciclo biolĂłgico de especies de monocotiledoneas. Por M. Ibarra, F. LĂłpez-Belmonte y MÂȘ A . Diez.-- Proteasas ĂĄcidas en uvas Vitis vinifera (variedad Macabeo). l. Actividad proteĂĄsica durante su maduraciĂłn. Por J. MarĂ­n ExpĂłsito, C. Miguel Gordillo, J. l. Maynar Mariño y J. L. Mesias Iglesias.-- Agro biologĂ­a Efectos de enmiendas calcĂĄreas en suelos fijadores de fĂłsforo. Por S. G. Ramos HernĂĄndez y N. Aguilera Herrera.-- III. Trabajo Recapitulativo. Una deriva hacia hemiparasftismo de los lĂ­quenes epifitos: AnĂĄlisis fisiolĂłgico de las relaciones con sus fitoforos. Por C. VicentePeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca IC

    Author Correction: Tree mode of death and mortality risk factors across Amazon forests

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    The original version of this Article contained an error in Table 2, where the number of individuals in the “All Amazonia” row was reported as 11,6431 instead of 116,431. Also, the original version of this Article contained an error in the Methods, where the R2 for the proportion of broken/uprooted dead trees increase per year was reported as 0.12, the correct value being 0.06. The original version of this Article contained errors in the author affiliations. The affiliation of Gerardo A. Aymard C. with UNELLEZGuanare, Herbario Universitario (PORT), Portuguesa, Venezuela Compensation International Progress S.A. Ciprogress–Greenlife.</p

    Tree mode of death and mortality risk factors across Amazon forests

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    The carbon sink capacity of tropical forests is substantially affected by tree mortality. However, the main drivers of tropical tree death remain largely unknown. Here we present a pan-Amazonian assessment of how and why trees die, analysing over 120,000 trees representing > 3800 species from 189 long-term RAINFOR forest plots. While tree mortality rates vary greatly Amazon-wide, on average trees are as likely to die standing as they are broken or uprooted—modes of death with different ecological consequences. Species-level growth rate is the single most important predictor of tree death in Amazonia, with faster-growing species being at higher risk. Within species, however, the slowest-growing trees are at greatest risk while the effect of tree size varies across the basin. In the driest Amazonian region species-level bioclimatic distributional patterns also predict the risk of death, suggesting that these forests are experiencing climatic conditions beyond their adaptative limits. These results provide not only a holistic pan-Amazonian picture of tree death but large-scale evidence for the overarching importance of the growth–survival trade-off in driving tropical tree mortality

    Author Correction: Tree mode of death and mortality risk factors across Amazon forests (Nature Communications, (2020), 11, 1, (5515), 10.1038/s41467-020-18996-3)

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    The original version of this Article contained an error in Table 2, where the number of individuals in the “All Amazonia” row was reported as 11,6431 instead of 116,431. Also, the original version of this Article contained an error in the Methods, where the R2 for the proportion of broken/uprooted dead trees increase per year was reported as 0.12, the correct value being 0.06. The original version of this Article contained errors in the author affiliations. The affiliation of Gerardo A. Aymard C. with UNELLEZGuanare, Herbario Universitario (PORT), Portuguesa, Venezuela Compensation International Progress S.A. Ciprogress–Greenlife

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

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    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 mĂĄs diversos y productivos del mundo y entender su funcionamiento es crĂ­tico 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. AquĂ­ mostramos cĂłmo una comunidad global estĂĄ respondiendo a los desafĂ­os de la investigaciĂłn en ecosistemas tropicales a travĂ©s de diversos equipos realizando mediciones ĂĄrbol por ĂĄrbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos mĂĄs importantes de este trabajo y discutimos cĂłmo este proceso estĂĄ cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexiĂłn de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a mĂșltiples escalas. Conectando investigadores tropicales, elevando su posiciĂłn y estatus, nuestro modelo de Red Social de InvestigaciĂłn reconoce el rol fundamental que tienen, para el descubrimiento cientĂ­fico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (SuramĂ©rica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiĂĄtico (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas estĂĄn integradas a travĂ©s de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 paĂ­ses en 24 redes diferentes de parcelas. Colectivamente, estas redes estĂĄn transformando nuestro conocimiento sobre los bosques tropicales y el rol de Ă©stos en la biĂłsfera. Juntos hemos descubierto cĂłmo, dĂłnde y porquĂ© el carbono y la biodiversidad de los bosques tropicales estĂĄ respondiendo al cambio climĂĄtico y cĂłmo se retroalimentan. Esta colaboraciĂłn pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuĂĄles son los factores mĂĄs importantes, quĂ© procesos se ven afectados, dĂłnde ocurren los cambios, los tiempos de reacciĂłn y las probables respuestas futuras mientras el clima continĂșa cambiando. Apalancando lo que realmente es una tecnologĂ­a antigua, las redes de parcelas estĂĄn generando una verdadera y moderna revoluciĂłn 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 informaciĂłn Ășnica y de largo plazo para entender los que probablemente son los bosques mĂĄs preciados de la tierra. Resumo Florestas tropicais sĂŁo os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensĂŁo destas florestas seja crucial para o nosso futuro coletivo, atĂ© muito recentemente os esforços de mediçÔes e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agĂȘncias financiadoras. Neste estudo nĂłs mostramos como uma comunidade global estĂĄ respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, ĂĄrvore por ĂĄrvore, em milhares de parcelas monitoradas Ă  longo prazo. NĂłs revisamos as maiores descobertas cientĂ­ficas deste trabalho, e mostramos tambĂ©m como este processo estĂĄ mudando a ciĂȘncia 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 cientĂ­fica. Concebida em 1999 com o RAINFOR (AmĂ©rica do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiĂĄtico (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas mĂșltiplas iniciativas estĂŁo integradas atravĂ©s de uma infraestrutura cibernĂ©tica do ForestPlots.net, conectando colegas de 54 paĂ­ses de 24 redes de parcelas. Estas iniciativas estĂŁo transformando coletivamente o entendimento das florestas tropicais e seus papĂ©is na biosfera. Juntos nĂłs descobrimos como, onde e por que o carbono e a biodiversidade da floresta estĂŁo respondendo Ă s mudanças climĂĄticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendĂȘncias, assim como tem evidenciado quais direcionadores sĂŁo mais importantes, quais processos florestais sĂŁo mais afetados, onde eles estĂŁo mudando, seus atrasos no tempo de resposta, e as provĂĄveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notĂĄvel tecnologia antiga, redes de parcelas acendem faĂ­scas de uma moderna revolução na ciĂȘncia das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora sĂŁo coletivamente capazes de gerar conhecimentos Ășnicos e duradouros sobre as florestas mais preciosas da Terra. RĂ©sume Les forĂȘts tropicales sont les Ă©cosystĂšmes les plus diversifiĂ©s et les plus productifs de la planĂšte. Si une meilleure comprĂ©hension de ces forĂȘts est essentielle pour notre avenir collectif, jusqu'Ă  tout rĂ©cemment, les efforts dĂ©ployĂ©s pour les mesurer et les surveiller ont Ă©tĂ© largement dĂ©connectĂ©s. La mise en rĂ©seau est essentielle pour dĂ©couvrir les rĂ©ponses Ă  des questions qui dĂ©passent les frontiĂšres et les horizons des organismes de financement. Nous montrons ici comment une communautĂ© mondiale relĂšve les dĂ©fis de la recherche sur les Ă©cosystĂšmes tropicaux avec diverses Ă©quipes qui mesurent les forĂȘts arbre aprĂšs arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales dĂ©couvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forĂȘts tropicales. Notre approche principale consiste Ă  relier les initiatives de base Ă  long terme Ă  des protocoles standardisĂ©s et une gestion de donnĂ©es afin de gĂ©nĂ©rer des rĂ©sultats solides Ă  grande Ă©chelle. En reliant les chercheurs tropicaux et en Ă©levant leur statut, notre modĂšle de rĂ©seau de recherche sociale reconnaĂźt le rĂŽle clĂ© de l'auteur des donnĂ©es dans la dĂ©couverte scientifique. Conçus en 1999 avec RAINFOR (AmĂ©rique du Sud), nos rĂ©seaux de parcelles permanentes ont Ă©tĂ© adaptĂ©s Ă  l'Afrique (AfriTRON) et Ă  l'Asie du Sud-Est (T-FORCES) et largement imitĂ©s dans le monde entier. Ces multiples initiatives sont dĂ©sormais intĂ©grĂ©es via l'infrastructure ForestPlots.net, qui relie des collĂšgues de 54 pays Ă  travers 24 rĂ©seaux de parcelles. Ensemble, elles transforment la comprĂ©hension des forĂȘts tropicales et de leur rĂŽle biosphĂ©rique. Ensemble, nous avons dĂ©couvert comment, oĂč et pourquoi le carbone forestier et la biodiversitĂ© rĂ©agissent au changement climatique, et comment ils y rĂ©agissent. Cette collaboration pan-tropicale Ă  long terme a rĂ©vĂ©lĂ© un important puits de carbone Ă  long terme et ses tendances, tout en mettant en Ă©vidence les facteurs les plus importants, les processus forestiers qui sont affectĂ©s, les endroits oĂč ils changent, les dĂ©calages et les rĂ©actions futures probables des forĂȘts tropicales Ă  mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les rĂ©seaux de parcelles dĂ©clenchent une rĂ©volution trĂšs moderne dans la science des forĂȘts tropicales. À l'avenir, l'humanitĂ© pourra grandement bĂ©nĂ©ficier du soutien des communautĂ©s de base qui sont maintenant collectivement capables de gĂ©nĂ©rer une comprĂ©hension unique et Ă  long terme des forĂȘts les plus prĂ©cieuses 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
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