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

A Fast Microwave-Assisted Procedure for Loss on Drying Determination in Saccharides

Um procedimento rápido para determinação de perda por dessecação (LOD) foi desenvolvido empregando aquecimento por radiação micro-ondas. Amostras de sacarídeos foram utilizadas e diferentes parâmetros foram avaliados, tais como a posição da amostra na cavidade do micro-ondas, massa de amostra e tempo de irradiação. Massas de amostra de 1 g e tempo de irradiação entre 15 e 25 min foram suficientes para a determinação da perda por dessecação de todos sacarídeos. Os resultados obtidos para perda por dessecação assistida por micro-ondas (MALOD) foram comparados com os resultados obtidos por LOD convencional em estufa e não apresentaram diferença significativa. O tempo de análise foi reduzido de 2,4 a 15 vezes, quando comparado ao sistema convencional de LOD e o desvio padrão relativo das medidas foi inferior a 1%. Até 16 amostras podem ser processadas simultaneamente, tornando o procedimento MALOD apropriado para análise de rotina. A fast procedure for loss on drying (LOD) determination was developed using microwave radiation. Samples of commercial saccharides were dried and the influence of sample position inside the microwave cavity, sample mass and irradiation time were evaluated. Sample mass of 1 g and irradiation time between 15 to 25 min were enough to LOD determination for all saccharides. Results obtained using the proposed microwave-assisted loss on drying (MALOD) procedure were compared with those obtained by conventional LOD determination using an oven and no statistical difference was found among results of these techniques. Using MALOD procedure the relative standard deviation was below 1%. The time for analysis was reduced from 2.4 to 15 times when compared to conventional LOD determination and up to 16 samples could be simultaneously processed making MALOD procedure suitable for routine analysis. Keywords: loss on drying, saccharides, microwave, food and pharmaceutical samples Introduction Loss on drying (LOD) determination is a parameter often evaluated to access the quality of products. Several applications of LOD can be found in industry, in special for food and pharmaceutical industries, which currently use LOD to determine the amount of volatile matter (in general, water) that is driven off under specific conditions. 1-3 The LOD determination is relatively simple to be performed and results with relatively good precision can be obtained resulting in a widespread use. For example, in the 30 th edition of The United States Pharmacopeia more than one thousand monographs recommended the use of LOD in their tests that makes it a parameter that must be routinely evaluated in current quality control. 14,15 Several papers dealing with microwave radiation for pharmaceuticals drying are available in the literature. Therefore, in this work the application of microwaves for LOD determination is proposed using simple and inexpensive instrumentation. Saccharide samples of pharmaceutical grade were chosen as examples in order to evaluate the feasibility of the proposed procedure and results were compared with those obtained by LOD using conventional heating in an oven described in The United States Pharmacopeia. Experimental Samples Commercially available saccharide samples of pharmaceutical grade (potato starch, maize starch, guar, agar, microcrystalline cellulose and hypromellose) were used in this work. Samples were maintained in their original package before LOD determinations in an environment with controlled temperature (22 ± 2 °C) and humidity (less than 50% of air relative humidity). All samples had particle size lower than 150 mm. Instrumentation Microwave-assisted loss on drying (MALOD) determination was performed using a domestic microwave oven (model BMK38ABBNA, 38 L, 2450 MHz, Brastemp, Brazil), with 950 W of nominal power. In order to allow a continuous microwave irradiation of samples and prevent damages to magnetron a polyethylene coil (1 m length and 5 mm i.d.) was fitted inside the cavity in the opposite side of the wave-guide. Water was passed within the coil in a constant flow rate (700 mL min -1 ). The polyethylene coil was passed through the microwave oven using the holes originally designed for air circulation in order to avoid changes in the metallic cavity cover and minimize the risk of microwave losses. For safety reasons, a microwave spill detector was periodically used during the experiments in order to check eventual microwave loss (model LT-2D, 2450 MHz, maximum limit of 5 mW cm -2 , Milestone S.R.L., Sorisole, Italy). For conventional LOD determination a drying oven (model 400/2ND, Nova Ética, Brazil) was used. Samples were dried in a weighing bottle of 25 mm of internal diameter and volume of 30 mL. Samples were accurately weighed using an analytical balance (model AY 220, max. 220 g, 0.1 mg of resolution, Shimadzu, Kyoto, Japan). Determination of microwave power output and distribution of microwave radiation within the oven cavity Ultrapure water (Milli-Q, 18.2 MW cm) was used for both determination of microwave power output and distribution of microwave radiation experiments. The power output of magnetron (real power) was indirectly determined by measuring the increase of temperature of water after microwave irradiation. In this work 1,000 g of water was heated at full power for 2 min and the power output of the microwave oven was evaluated using a general relationship where the power output (P), in Watts, was calculated according to equation 1: P = k cp m ΔT/t, where k is the conversion factor (from thermal chemical calories s -1 to Watts, 4.184 J cal ), m is the sample mass (g), ΔT is the temperature change (°C) after microwave heating, and t is the time of irradiation (s). 24 A Fast Microwave-Assisted Procedure for Loss on Drying Determination in Saccharides J. Braz. Chem. Soc. 378 In order to evaluate the influence of sample position inside the microwave cavity on the heating of samples, twenty one glass beakers (25 mm diameter and 20 mL capacity) each one containing 15 g of ultrapure water were symmetrically positioned on the turntable of the microwave cavity. The oven was operated at maximum power for 60 s of irradiation. The temperature increase of water was measured with a thermocouple device (digital thermometer, model AF0806, Incoterm, Brazil). This procedure was performed by measuring the temperature, each run, of four beakers positioned at the same distance from the center. Further, for all the beakers, water was replaced by a new amount of cold water and the same procedure was performed for beakers positioned in other distances from the center. This procedure was repeated up to the water temperature has been determined in all the 20 beakers. Therefore, microwave distribution inside the oven was determined using this procedure. This procedure was repeated four-times and the mean absorbed power for each position was calculated according to equation 1. LOD and MALOD determination The LOD determination in conventional oven was performed by introduction of 1 g of each sample in a weighing bottle previously dried under the recommended conditions (130 °C for potato and maize starch and 100 to 105 °C for the other samples) up to constant mass. For MALOD determination the influence of microwave irradiation time and sample amount were evaluated from 1 to 30 min and from 0.5 to 2.0 g of saccharide samples, respectively. Samples were dried in weighing bottles, which were previously prepared under the same conditions described for LOD determination in an oven. The kinetics of drying for the MALOD procedure was evaluated by means of relative dielectric loss factor determination. 14 For this study, 4.0 ± 0.1 g of sample were dried in the microwave oven at the maximum power for 30 s. The temperature increase was determined using a thermocouple device with digital display for both dried and non dried samples. Each experiment was repeated four times. Results and Discussion Determination of microwave power output and distribution of microwave radiation within the oven cavity Considering that domestic microwave ovens are not originally designed for analytical purposes the evaluation of total irradiated microwave power and microwave distribution inside the cavity was necessary. Influence of microwave irradiation time for MALOD As can be seen in 14,27,33 Thus, an indication of the relative magnitude of the dielectric characteristics may be obtained by measuring the temperature variation induced when the sample was irradiated with microwaves. In the present work, the drying profile of saccharides could be considered as a function of relative dielectric loss factor, as shown in 14 During the first falling-rate period, a higher amount of free water was present. Therefore, in view of the higher dielectric loss factor of water, microwaves could be selectively absorbed by these molecules thus facilitating a high drying-rate. During the drying process, the solid content becomes more significant and therefore the solid sample begins to absorb a greater proportion of microwave energy. Therefore, the initial amount of water present in the samples had great influence on the microwave drying profile of saccharides samples. The necessary time to achieve a constant mass was 15 min for maize starch, guar, hypromellose and microcrystalline cellulose, and 20 to 25 min for potato starch and agar, respectively as shown in Influence of sample mass The influence of sample mass on MALOD determination was evaluated using the previously selected time of irradiation observed for each saccharyde (before section). With the increase of mass the loss on A Fast Microwave-Assisted Procedure for Loss on Drying Determination in Saccharides J. Braz. Chem. Soc. 380 drying was constant as shown in 2 Therefore, it was not considered a limitation for LOD determination using the proposed procedure. Comparison of proposed MALOD with LOD An advantage of the drying oven process is related to the fact that this simple technique can be carried out in practically every analytical laboratory. In spite that this technique provides reproducible results, the LOD using an oven cannot be regarded as a rapid determination method due to the excessive time for determination. It could reduce the throughput for routine analysis. The recommended time for LOD determination using an oven described in pharmacopeias ranges from 90 min (e.g. maize and potato starch) to 300 min (e.g. guar and agar samples). 2 Using the proposed MALOD procedure, the time for drying all the samples was between 15 and 25 min resulting in a time reduction up to 15 times (for guar sample) as can be seen in Furthermore, the results obtained with proposed procedure were in agreement (t-Test, 95% of confidence level) to those obtained by conventional LOD determination using an oven as shown in Conclusions The proposed MALOD procedure provided results comparable to conventional LOD for evaluated samples in a faster way. For some saccharides, carbonized spots were observed when the time was increased beyond 20 min (microcrystalline cellulose) and with masses higher than 1.5 g (guar and microcrystalline cellulose) or 2.0 g (potato starch, maize starch, agar and hypromellose). In addition, the relative standard deviations for MALOD were considered suitable for routine LOD determination. Reduced time for analysis can be cited as the mainly advantage of MALOD when compared to conventional LOD determination. Therefore, MALOD procedure can be recommended as an alternative method to LOD determination in saccharides samples. To the best of our knowledge, the present work describes the first application of microwaves for LOD determination in pharmaceutical products related to the specifications of pharmacopeias