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1. Automatic Cerebral Vessel Extraction in TOF-MRA Using Deep Learning

Author

de Vos, V., Timmins, K. M., van der Schaaf, I. C., Ruigrok, Y., Velthuis, B. K., and Kuijf, H. J.

Subjects
Electrical Engineering and Systems Science - Image and Video Processing, Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning
Abstract

Deep learning approaches may help radiologists in the early diagnosis and timely treatment of cerebrovascular diseases. Accurate cerebral vessel segmentation of Time-of-Flight Magnetic Resonance Angiographs (TOF-MRAs) is an essential step in this process. This study investigates deep learning approaches for automatic, fast and accurate cerebrovascular segmentation for TOF-MRAs. The performance of several data augmentation and selection methods for training a 2D and 3D U-Net for vessel segmentation was investigated in five experiments: a) without augmentation, b) Gaussian blur, c) rotation and flipping, d) Gaussian blur, rotation and flipping and e) different input patch sizes. All experiments were performed by patch-training both a 2D and 3D U-Net and predicted on a test set of MRAs. Ground truth was manually defined using an interactive threshold and region growing method. The performance was evaluated using the Dice Similarity Coefficient (DSC), Modified Hausdorff Distance and Volumetric Similarity, between the predicted images and the interactively defined ground truth. The segmentation performance of all trained networks on the test set was found to be good, with DSC scores ranging from 0.72 to 0.83. Both the 2D and 3D U-Net had the best segmentation performance with Gaussian blur, rotation and flipping compared to other experiments without augmentation or only one of those augmentation techniques. Additionally, training on larger patches or slices gave optimal segmentation results. In conclusion, vessel segmentation can be optimally performed on TOF-MRAs using a trained 3D U-Net on larger patches, where data augmentation including Gaussian blur, rotation and flipping was performed on the training data., Comment: Preprint for the SPIE Medical Imaging, Image Processing Conference 2021

Published
2021

2. Persistent effects of pre-Columbian plant domestication on Amazonian forest composition

Author

Levis, C., Costa, F. R. C., Bongers, F., Peña-Claros, M., Clement, C. R., Junqueira, A. B., Neves, E. G., Tamanaha, E. K., Figueiredo, F. O. G., Salomão, R. P., Castilho, C. V., Magnusson, W. E., Phillips, O. L., Guevara, J. E., Sabatier, D., Molino, J.-F., López, D. Cárdenas, Mendoza, A. M., Pitman, N. C. A., Duque, A., Vargas, P. Núñez, Zartman, C. E., Vasquez, R., Andrade, A., Camargo, J. L., Feldpausch, T. R., Laurance, S. G. W., Laurance, W. F., Killeen, T. J., Nascimento, H. E. Mendonça, Montero, J. C., Mostacedo, B., Amaral, I. L., Vieira, I. C. Guimarães, Brienen, R., Castellanos, H., Terborgh, J., de Jesus Veiga Carim, M., da Silva Guimarães, J. R., de Souza Coelho, L., de Almeida Matos, F. D., Wittmann, F., Mogollón, H. F., Damasco, G., Dávila, N., García-Villacorta, R., Coronado, E. N. H., Emilio, T., de Andrade Lima Filho, D., Schietti, J., Souza, P., Targhetta, N., Comiskey, J. A., Marimon, B. S., Marimon, B.-H., Neill, D., Alonso, A., Arroyo, L., Carvalho, F. A., de Souza, F. C., Dallmeier, F., Pansonato, M. P., Duivenvoorden, J. F., Fine, P. V. A., Stevenson, P. R., Araujo-Murakami, A., Aymard C., G. A., Baraloto, C., do Amaral, D. D., Engel, J., Henkel, T. W., Maas, P., Petronelli, P., Revilla, J. D. Cardenas, Stropp, J., Daly, D., Gribel, R., Paredes, M. Ríos, Silveira, M., Thomas-Caesar, R., Baker, T. R., da Silva, N. F., Ferreira, L. V., Peres, C. A., Silman, M. R., Cerón, C., Valverde, F. C., Di Fiore, A., Jimenez, E. M., Mora, M. C. Peñuela, Toledo, M., Barbosa, E. M., de Matos Bonates, L. C., Arboleda, N. C., de Sousa Farias, E., Fuentes, A., Guillaumet, J.-L., Jørgensen, P. Møller, Malhi, Y., de Andrade Miranda, I. P., Phillips, J. F., Prieto, A., Rudas, A., Ruschel, A. R., Silva, N., von Hildebrand, P., Vos, V. A., Zent, E. L., Zent, S., Cintra, B. B. L., Nascimento, M. T., Oliveira, A. A., Ramirez-Angulo, H., Ramos, J. F., Rivas, G., Schöngart, J., Sierra, R., Tirado, M., van der Heijden, G., Torre, E. V., Wang, O., Young, K. R., Baider, C., Cano, A., Farfan-Rios, W., Ferreira, C., Hoffman, B., Mendoza, C., Mesones, I., Torres-Lezama, A., Medina, M. N. U., van Andel, T. R., Villarroel, D., Zagt, R., Alexiades, M. N., Balslev, H., Garcia-Cabrera, K., Gonzales, T., Hernandez, L., Huamantupa-Chuquimaco, I., Manzatto, A. G., Milliken, W., Cuenca, W. P., Pansini, S., Pauletto, D., Arevalo, F. R., Reis, N. F. Costa, Sampaio, A. F., Giraldo, L. E. Urrego, Sandoval, E. H. Valderrama, Gamarra, L. Valenzuela, Vela, C. I. A., and ter Steege, H.

Published
2017

3. Hydrology as a Driver of Floating River Plastic Transport

Author

van Emmerik, T., primary, de Lange, S., additional, Frings, R., additional, Schreyers, L., additional, Aalderink, H., additional, Leusink, J., additional, Begemann, F., additional, Hamers, E., additional, Hauk, R., additional, Janssens, N., additional, Jansson, P., additional, Joosse, N., additional, Kelder, D., additional, van der Kuijl, T., additional, Lotcheris, R., additional, Löhr, A., additional, Mellink, Y., additional, Pinto, R., additional, Tasseron, P., additional, Vos, V., additional, and Vriend, P., additional

Published
2022
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5. Hydrology as a Driver of Floating River Plastic Transport

Author

van Emmerik, T., de Lange, S., Frings, R., Schreyers, L., Aalderink, H., Leusink, J., Begemann, F., Hamers, E., Hauk, R., Janssens, N., Jansson, P., Joosse, N., Kelder, D., van der Kuijl, T., Lotcheris, R., Löhr, A., Mellink, Y., Pinto, R., Tasseron, P., Vos, V., Vriend, P., van Emmerik, T., de Lange, S., Frings, R., Schreyers, L., Aalderink, H., Leusink, J., Begemann, F., Hamers, E., Hauk, R., Janssens, N., Jansson, P., Joosse, N., Kelder, D., van der Kuijl, T., Lotcheris, R., Löhr, A., Mellink, Y., Pinto, R., Tasseron, P., Vos, V., and Vriend, P.

Abstract

Plastic pollution in aquatic ecosystems is a growing threat to ecosystem health and human livelihood. Recent studies show that the majority of environmental plastics accumulate within river systems for years, decades and potentially even longer. Long-term and system-scale observations are key to improve the understanding of transport and retention dynamics, to identify sources and sinks, and to assess potential risks. The goal of this study was to quantify and explain the variation in floating plastic transport in the Rhine-Meuse delta, using a novel 1-year observational data set. We found a strong positive correlations between floating plastic transport and discharge. During peak discharge events, plastic transport was found up to six times higher than under normal conditions. Plastic transport varied up to a factor four along the Rhine and Meuse rivers, which is hypothesized to be related to the complex river network, locations of urban areas, and tidal dynamics. Altogether, our findings demonstrate the important role of hydrology as driving force of plastic transport dynamics. Our study emphasizes the need for exploring other factors that may explain the spatiotemporal variation in floating plastic transport. The world's most polluted rivers are connected to the ocean through complex deltas. Providing reliable observations and data-driven insights in the transport and dynamics are key to optimize plastic pollution prevention and reduction strategies. With our paper we aim to contribute to both advancing the fundamental understanding of plastic transport dynamics, and the establishment of long-term and harmonized data collection at the river basin scale.

Published
2022

6. The number of tree species on Earth

Author

Cazzolla Gatti, R., Reich, P., Gamarra, J., Crowther, T., Hui, C., Morera, A., Bastin, J.-F., de-Miguel, S., Nabuurs, G.-J., Svenning, J.-C., Serra-Diaz, J., Merow, C., Enquist, B., Kamenetsky, M., Lee, J., Zhu, J., Fang, J., Jacobs, D., Pijanowski, B., Banerjee, A., Giaquinto, R., Alberti, G., Almeyda Zambrano, A., Alvarez-Davila, E., Araujo-Murakami, A., Avitabile, V., Aymard, G., Balazy, R., Baraloto, C., Barroso, J., Bastian, M., Birnbaum, P., Bitariho, R., Bogaert, J., Bongers, F., Bouriaud, O., Brancalion, P., Brearley, F., Broadbent, E., Bussotti, F., Castro da Silva, W., César, R., Češljar, G., Chama Moscoso, V., Chen, H., Cienciala, E., Clark, C., Coomes, D., Dayanandan, S., Decuyper, M., Dee, L., Del Aguila Pasquel, J., Derroire, G., Djuikouo, M., Van Do, T., Dolezal, J., Đorđević, I., Engel, J., Fayle, T., Feldpausch, T., Fridman, J., Harris, D., Hemp, A., Hengeveld, G., Herault, B., Herold, M., Ibanez, T., Jagodzinski, A., Jaroszewicz, B., Jeffery, K., Johannsen, V., Jucker, T., Kangur, A., Karminov, V., Kartawinata, K., Kennard, D., Kepfer-Rojas, S., Keppel, G., Khan, M., Khare, P., Kileen, T., Kim, H., Korjus, H., Kumar, A., Laarmann, D., Labrière, N., Lang, M., Lewis, S., Lukina, N., Maitner, B., Malhi, Y., Marshall, A., Martynenko, O., Monteagudo Mendoza, A., Ontikov, P., Ortiz-Malavasi, E., Pallqui Camacho, N., Paquette, A., Park, M., Parthasarathy, N., Peri, P., Petronelli, P., Pfautsch, S., Phillips, O., Picard, N., Piotto, D., Poorter, L., Poulsen, J., Pretzsch, H., Ramírez-Angulo, H., Restrepo Correa, Z., Rodeghiero, M., Rojas Gonzáles, R., Rolim, S., Rovero, F., Rutishauser, E., Saikia, P., Salas-Eljatib, C., Shchepashchenko, D., Scherer-Lorenzen, M., Šebeň, V., Silveira, M., Slik, F., Sonké, B., Souza, A., Stereńczak, K., Svoboda, M., Taedoumg, H., Tchebakova, N., Terborgh, J., Tikhonova, E., Torres-Lezama, A., van der Plas, F., Vásquez, R., Viana, H., Vibrans, A., Vilanova, E., Vos, V., Wang, H.-F., Westerlund, B., White, L., Wiser, S., Zawiła-Niedźwiecki, T., Zemagho, L., Zhu, Z., Zo-Bi, I., Liang, J., Cazzolla Gatti, R., Reich, P., Gamarra, J., Crowther, T., Hui, C., Morera, A., Bastin, J.-F., de-Miguel, S., Nabuurs, G.-J., Svenning, J.-C., Serra-Diaz, J., Merow, C., Enquist, B., Kamenetsky, M., Lee, J., Zhu, J., Fang, J., Jacobs, D., Pijanowski, B., Banerjee, A., Giaquinto, R., Alberti, G., Almeyda Zambrano, A., Alvarez-Davila, E., Araujo-Murakami, A., Avitabile, V., Aymard, G., Balazy, R., Baraloto, C., Barroso, J., Bastian, M., Birnbaum, P., Bitariho, R., Bogaert, J., Bongers, F., Bouriaud, O., Brancalion, P., Brearley, F., Broadbent, E., Bussotti, F., Castro da Silva, W., César, R., Češljar, G., Chama Moscoso, V., Chen, H., Cienciala, E., Clark, C., Coomes, D., Dayanandan, S., Decuyper, M., Dee, L., Del Aguila Pasquel, J., Derroire, G., Djuikouo, M., Van Do, T., Dolezal, J., Đorđević, I., Engel, J., Fayle, T., Feldpausch, T., Fridman, J., Harris, D., Hemp, A., Hengeveld, G., Herault, B., Herold, M., Ibanez, T., Jagodzinski, A., Jaroszewicz, B., Jeffery, K., Johannsen, V., Jucker, T., Kangur, A., Karminov, V., Kartawinata, K., Kennard, D., Kepfer-Rojas, S., Keppel, G., Khan, M., Khare, P., Kileen, T., Kim, H., Korjus, H., Kumar, A., Laarmann, D., Labrière, N., Lang, M., Lewis, S., Lukina, N., Maitner, B., Malhi, Y., Marshall, A., Martynenko, O., Monteagudo Mendoza, A., Ontikov, P., Ortiz-Malavasi, E., Pallqui Camacho, N., Paquette, A., Park, M., Parthasarathy, N., Peri, P., Petronelli, P., Pfautsch, S., Phillips, O., Picard, N., Piotto, D., Poorter, L., Poulsen, J., Pretzsch, H., Ramírez-Angulo, H., Restrepo Correa, Z., Rodeghiero, M., Rojas Gonzáles, R., Rolim, S., Rovero, F., Rutishauser, E., Saikia, P., Salas-Eljatib, C., Shchepashchenko, D., Scherer-Lorenzen, M., Šebeň, V., Silveira, M., Slik, F., Sonké, B., Souza, A., Stereńczak, K., Svoboda, M., Taedoumg, H., Tchebakova, N., Terborgh, J., Tikhonova, E., Torres-Lezama, A., van der Plas, F., Vásquez, R., Viana, H., Vibrans, A., Vilanova, E., Vos, V., Wang, H.-F., Westerlund, B., White, L., Wiser, S., Zawiła-Niedźwiecki, T., Zemagho, L., Zhu, Z., Zo-Bi, I., and Liang, J.

Abstract

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness.

Published
2022

7. Long-term decline of the Amazon carbon sink

Author

Brienen, R. J. W., Phillips, O. L., Feldpausch, T. R., Gloor, E., Baker, T. R., Lloyd, J., Lopez-Gonzalez, G., Monteagudo-Mendoza, A., Malhi, Y., Lewis, S. L., Vásquez Martinez, R., Alexiades, M., Álvarez Dávila, E., Alvarez-Loayza, P., Andrade, A., Aragão, L. E. O. C., Araujo-Murakami, A., Arets, E. J. M. M., Arroyo, L., Aymard, G. A. C., Bánki, O. S., Baraloto, C., Barroso, J., Bonal, D., Boot, R. G. A., Camargo, J. L. C., Castilho, C. V., Chama, V., Chao, K. J., Chave, J., Comiskey, J. A., Cornejo Valverde, F., da Costa, L., de Oliveira, E. A., Di Fiore, A., Erwin, T. L., Fauset, S., Forsthofer, M., Galbraith, D. R., Grahame, E. S., Groot, N., Hérault, B., Higuchi, N., Honorio Coronado, E. N., Keeling, H., Killeen, T. J., Laurance, W. F., Laurance, S., Licona, J., Magnussen, W. E., Marimon, B. S., Marimon-Junior, B. H., Mendoza, C., Neill, D. A., Nogueira, E. M., Núñez, P., Pallqui Camacho, N. C., Parada, A., Pardo-Molina, G., Peacock, J., Peña-Claros, M., Pickavance, G. C., Pitman, N. C. A., Poorter, L., Prieto, A., Quesada, C. A., Ramírez, F., Ramírez-Angulo, H., Restrepo, Z., Roopsind, A., Rudas, A., Salomão, R. P., Schwarz, M., Silva, N., Silva-Espejo, J. E., Silveira, M., Stropp, J., Talbot, J., ter Steege, H., Teran-Aguilar, J., Terborgh, J., Thomas-Caesar, R., Toledo, M., Torello-Raventos, M., Umetsu, R. K., van der Heijden, G. M. F., van der Hout, P., Guimarães Vieira, I. C., Vieira, S. A., Vilanova, E., Vos, V. A., and Zagt, R. J.

Published
2015
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9. Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Author

Blundo, C, Carilla, J, Grau, R, Malizia, A, Malizia, L, Osinaga-Acosta, O, Bird, M, Bradford, M, Catchpole, D, Ford, A, Graham, A, Hilbert, D, Kemp, J, Laurance, S, Laurance, W, Ishida, FY, Marshall, A, Waite, C, Woell, H, Bastin, JF, Bauters, M, Beeckman, H, Boeckx, P, Bogaert, J, De Canniere, C, de Haulleville, T, Doucet, JL, Hardy, O, Hubau, W, Kearsley, E, Verbeeck, H, Vleminckx, J, Brewer, SW, Alarcón, A, Araujo-Murakami, A, Arets, E, Arroyo, L, Chavez, E, Fredericksen, T, Villaroel, RG, Sibauty, GG, Killeen, T, Licona, JC, Lleigue, J, Mendoza, C, Murakami, S, Gutierrez, AP, Pardo, G, Peña-Claros, M, Poorter, L, Toledo, M, Cayo, JV, Viscarra, LJ, Vos, V, Ahumada, J, Almeida, E, Almeida, J, de Oliveira, EA, da Cruz, WA, de Oliveira, AA, Carvalho, FA, Obermuller, FA, Andrade, A, Vieira, SA, Aquino, AC, Aragão, L, Araújo, AC, Assis, MA, Gomes, JAMA, Baccaro, F, de Camargo, PB, Barni, P, Barroso, J, Bernacci, LC, Bordin, K, de Medeiros, MB, Broggio, I, Camargo, JL, Cardoso, D, Carniello, MA, Rochelle, ALC, Castilho, C, Castro, AAJF, Castro, W, Ribeiro, SC, Costa, F, de Oliveira, RC, Coutinho, I, Cunha, J, da Costa, L, da Costa Ferreira, L, da Costa Silva, R, da Graça Zacarias Simbine, M, de Andrade Kamimura, V, de Lima, HC, de Oliveira Melo, L, de Queiroz, L, de Sousa Lima, JR, do Espírito Santo, M, Blundo, C, Carilla, J, Grau, R, Malizia, A, Malizia, L, Osinaga-Acosta, O, Bird, M, Bradford, M, Catchpole, D, Ford, A, Graham, A, Hilbert, D, Kemp, J, Laurance, S, Laurance, W, Ishida, FY, Marshall, A, Waite, C, Woell, H, Bastin, JF, Bauters, M, Beeckman, H, Boeckx, P, Bogaert, J, De Canniere, C, de Haulleville, T, Doucet, JL, Hardy, O, Hubau, W, Kearsley, E, Verbeeck, H, Vleminckx, J, Brewer, SW, Alarcón, A, Araujo-Murakami, A, Arets, E, Arroyo, L, Chavez, E, Fredericksen, T, Villaroel, RG, Sibauty, GG, Killeen, T, Licona, JC, Lleigue, J, Mendoza, C, Murakami, S, Gutierrez, AP, Pardo, G, Peña-Claros, M, Poorter, L, Toledo, M, Cayo, JV, Viscarra, LJ, Vos, V, Ahumada, J, Almeida, E, Almeida, J, de Oliveira, EA, da Cruz, WA, de Oliveira, AA, Carvalho, FA, Obermuller, FA, Andrade, A, Vieira, SA, Aquino, AC, Aragão, L, Araújo, AC, Assis, MA, Gomes, JAMA, Baccaro, F, de Camargo, PB, Barni, P, Barroso, J, Bernacci, LC, Bordin, K, de Medeiros, MB, Broggio, I, Camargo, JL, Cardoso, D, Carniello, MA, Rochelle, ALC, Castilho, C, Castro, AAJF, Castro, W, Ribeiro, SC, Costa, F, de Oliveira, RC, Coutinho, I, Cunha, J, da Costa, L, da Costa Ferreira, L, da Costa Silva, R, da Graça Zacarias Simbine, M, de Andrade Kamimura, V, de Lima, HC, de Oliveira Melo, L, de Queiroz, L, de Sousa Lima, JR, and do Espírito Santo, M

Abstract

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 sc

Published
2021

10. Amazon tree dominance across forest strata

Author

Draper, F.C., Costa, F.R.C., Arellano, G., Phillips, O.L., Duque, A., Macía, M.J., ter Steege, H., Asner, G.P., Berenguer, E., Schietti, J., Socolar, J.B., de Souza, F.C., Dexter, K.G., Jørgensen, P.M., Tello, J.S., Magnusson, W.E., Baker, T.R., Castilho, C.V., Monteagudo-Mendoza, A., Fine, P.V.A., Ruokolainen, K., Coronado, E.N.H., Aymard, G., Dávila, N., Sáenz, M.S., Paredes, M.A.R., Engel, J., Fortunel, C., Paine, C.E.T., Goret, J.-Y., Dourdain, A., Petronelli, P., Allie, E., Andino, J.E.G., Brienen, R.J.W., Pérez, L.C., Manzatto, Â.G., Zambrana, N.Y.P., Molino, J.-F., Sabatier, D., Chave, J., Fauset, S., Villacorta, R.G., Réjou-Méchain, M., Berry, P.E., Melgaço, K., Feldpausch, T.R., Sandoval, E.V., Martinez, R.V., Mesones, I., Junqueira, A.B., Roucoux, K.H., de Toledo, J.J., Andrade, A.C., Camargo, J.L., del Aguila Pasquel, J., Santana, F.D., Laurance, W.F., Laurance, S.G., Lovejoy, T.E., Comiskey, J.A., Galbraith, D.R., Kalamandeen, M., Aguilar, G.E.N., Arenas, J.V., Guerra, C.A.A., Flores, M., Llampazo, G.F., Montenegro, L.A.T., Gomez, R.Z., Pansonato, M.P., Moscoso, V.C., Vleminckx, J., Barrantes, O.J.V., Duivenvoorden, J.F., de Sousa, S.A., Arroyo, L., Perdiz, R.O., Cravo, J.S., Marimon, B.S., Junior, B.H.M., Carvalho, F.A., Damasco, G., Disney, M., Vital, M.S., Diaz, P.R.S., Vicentini, A., Nascimento, H., Higuchi, N., Van Andel, T., Malhi, Y., Ribeiro, S.C., Terborgh, J.W., Thomas, R.S., Dallmeier, F., Prieto, A., Hilário, R.R., Salomão, R.P., Silva, R.C., Casas, L.F., Vieira, I.C.G., Araujo-Murakami, A., Arevalo, F.R., Ramírez-Angulo, H., Torre, E.V., Peñuela, M.C., Killeen, T.J., Pardo, G., Jimenez-Rojas, E., Castro, W., Cabrera, D.G., Pipoly, J., de Sousa, T.R., Silvera, M., Vos, V., Neill, D., Vargas, P.N., Vela, D.M., Aragão, L.E.O.C., Umetsu, R.K., Sierra, R., Wang, O., Young, K.R., Prestes, N.C.C.S., Massi, K.G., Huaymacari, J.R., Gutierrez, G.A.P., Aldana, A.M., Alexiades, M.N., Baccaro, F., Céron, C., Muelbert, A.E., Rios, J.M.G., Lima, A.S., Lloyd, J.L., Pitman, N.C.A., Gamarra, L.V., Oroche, C.J.C., Fuentes, A.F., Palacios, W., Patiño, S., Torres-Lezama, A., Baraloto, C., Draper, F.C., Costa, F.R.C., Arellano, G., Phillips, O.L., Duque, A., Macía, M.J., ter Steege, H., Asner, G.P., Berenguer, E., Schietti, J., Socolar, J.B., de Souza, F.C., Dexter, K.G., Jørgensen, P.M., Tello, J.S., Magnusson, W.E., Baker, T.R., Castilho, C.V., Monteagudo-Mendoza, A., Fine, P.V.A., Ruokolainen, K., Coronado, E.N.H., Aymard, G., Dávila, N., Sáenz, M.S., Paredes, M.A.R., Engel, J., Fortunel, C., Paine, C.E.T., Goret, J.-Y., Dourdain, A., Petronelli, P., Allie, E., Andino, J.E.G., Brienen, R.J.W., Pérez, L.C., Manzatto, Â.G., Zambrana, N.Y.P., Molino, J.-F., Sabatier, D., Chave, J., Fauset, S., Villacorta, R.G., Réjou-Méchain, M., Berry, P.E., Melgaço, K., Feldpausch, T.R., Sandoval, E.V., Martinez, R.V., Mesones, I., Junqueira, A.B., Roucoux, K.H., de Toledo, J.J., Andrade, A.C., Camargo, J.L., del Aguila Pasquel, J., Santana, F.D., Laurance, W.F., Laurance, S.G., Lovejoy, T.E., Comiskey, J.A., Galbraith, D.R., Kalamandeen, M., Aguilar, G.E.N., Arenas, J.V., Guerra, C.A.A., Flores, M., Llampazo, G.F., Montenegro, L.A.T., Gomez, R.Z., Pansonato, M.P., Moscoso, V.C., Vleminckx, J., Barrantes, O.J.V., Duivenvoorden, J.F., de Sousa, S.A., Arroyo, L., Perdiz, R.O., Cravo, J.S., Marimon, B.S., Junior, B.H.M., Carvalho, F.A., Damasco, G., Disney, M., Vital, M.S., Diaz, P.R.S., Vicentini, A., Nascimento, H., Higuchi, N., Van Andel, T., Malhi, Y., Ribeiro, S.C., Terborgh, J.W., Thomas, R.S., Dallmeier, F., Prieto, A., Hilário, R.R., Salomão, R.P., Silva, R.C., Casas, L.F., Vieira, I.C.G., Araujo-Murakami, A., Arevalo, F.R., Ramírez-Angulo, H., Torre, E.V., Peñuela, M.C., Killeen, T.J., Pardo, G., Jimenez-Rojas, E., Castro, W., Cabrera, D.G., Pipoly, J., de Sousa, T.R., Silvera, M., Vos, V., Neill, D., Vargas, P.N., Vela, D.M., Aragão, L.E.O.C., Umetsu, R.K., Sierra, R., Wang, O., Young, K.R., Prestes, N.C.C.S., Massi, K.G., Huaymacari, J.R., Gutierrez, G.A.P., Aldana, A.M., Alexiades, M.N., Baccaro, F., Céron, C., Muelbert, A.E., Rios, J.M.G., Lima, A.S., Lloyd, J.L., Pitman, N.C.A., Gamarra, L.V., Oroche, C.J.C., Fuentes, A.F., Palacios, W., Patiño, S., Torres-Lezama, A., and Baraloto, C.

Abstract

The forests of Amazonia are among the most biodiverse plant communities on Earth. Given the immediate threats posed by climate and land-use change, an improved understanding of how this extraordinary biodiversity is spatially organized is urgently required to develop effective conservation strategies. Most Amazonian tree species are extremely rare but a few are common across the region. Indeed, just 227 ‘hyperdominant’ species account for >50% of all individuals >10 cm diameter at 1.3 m in height. Yet, the degree to which the phenomenon of hyperdominance is sensitive to tree size, the extent to which the composition of dominant species changes with size class and how evolutionary history constrains tree hyperdominance, all remain unknown. Here, we use a large floristic dataset to show that, while hyperdominance is a universal phenomenon across forest strata, different species dominate the forest understory, midstory and canopy. We further find that, although species belonging to a range of phylogenetically dispersed lineages have become hyperdominant in small size classes, hyperdominants in large size classes are restricted to a few lineages. Our results demonstrate that it is essential to consider all forest strata to understand regional patterns of dominance and composition in Amazonia. More generally, through the lens of 654 hyperdominant species, we outline a tractable pathway for understanding the functioning of half of Amazonian forests across vertical strata and geographical locations.

Published
2021

11. Long-term thermal sensitivity of Earth's tropical forests

Author

Sullivan, M.J.P., Lewis, S.L., Affum-Baffoe, K., Castilho, C., Costa, F., Sanchez, A.C., Ewango, C.E.N., Hubau, W., Marimon, B., Monteagudo-Mendoza, A., Qie, L., Sonké, B., Martinez, R.V., Baker, T.R., Brienen, R.J.W., Feldpausch, T.R., Galbraith, D., Gloor, M., Malhi, Y., Aiba, S.-I., Alexiades, M.N., Almeida, E.C., de Oliveira, E.A., Dávila, E.Á., Loayza, P.A., Andrade, A., Vieira, S.A., Aragão, L.E.O.C., Araujo-Murakami, A., Arets, E.J.M.M., Arroyo, L., Ashton, P., Aymard C, G., Baccaro, F.B., Banin, L.F., Baraloto, C., Camargo, P.B., Barlow, J., Barroso, J., Bastin, J.-F., Batterman, S.A., Beeckman, H., Begne, S.K., Bennett, A.C., Berenguer, E., Berry, N., Blanc, L., Boeckx, P., Bogaert, J., Bonal, D., Bongers, F., Bradford, M., Brearley, F.Q., Brncic, T., Brown, F., Burban, B., Camargo, J.L., Castro, W., Céron, C., Ribeiro, S.C., Moscoso, V.C., Chave, J., Chezeaux, E., Clark, C.J., de Souza, F.C., Collins, M., Comiskey, J.A., Valverde, F.C., Medina, M.C., da Costa, L., Dančák, M., Dargie, G.C., Davies, S., Cardozo, N.D., de Haulleville, T., de Medeiros, M.B., Del Aguila Pasquel, J., Derroire, G., Di Fiore, A., Doucet, J.-L., Dourdain, A., Droissant, V., Duque, L.F., Ekoungoulou, R., Elias, F., Erwin, T., Esquivel-Muelbert, A., Fauset, S., Ferreira, J., Llampazo, G.F., Foli, E., Ford, A., Gilpin, M., Hall, J.S., Hamer, K.C., Hamilton, A.C., Harris, D.J., Hart, T.B., Hédl, R., Herault, B., Herrera, R., Higuchi, N., Hladik, A., Coronado, E.H., Huamantupa-Chuquimaco, I., Huasco, W.H., Jeffery, K.J., Jimenez-Rojas, E., Kalamandeen, M., Djuikouo, M.N.K., Kearsley, E., Umetsu, R.K., Kho, L.K., Killeen, T., Kitayama, K., Klitgaard, B., Koch, A., Labrière, N., Laurance, W., Laurance, S., Leal, M.E., Levesley, A., Lima, A.J.N., Lisingo, J., Lopes, A.P., Lopez-Gonzalez, G., Lovejoy, T., Lovett, J.C., Lowe, R., Magnusson, W.E., Malumbres-Olarte, J., Manzatto, ÂG., Marimon B.H., Jr, Marshall, A.R., Marthews, T., de Almeida Reis, S.M., Maycock, C., Melgaço, K., Mendoza, C., Metali, F., Mihindou, V., Milliken, W., Mitchard, E.T.A., Morandi, P.S., Mossman, H.L., Nagy, L., Nascimento, H., Neill, D., Nilus, R., Vargas, P.N., Palacios, W., Camacho, N.P., Peacock, J., Pendry, C., Peñuela Mora, M.C., Pickavance, G.C., Pipoly, J., Pitman, N., Playfair, M., Poorter, L., Poulsen, J.R., Poulsen, A.D., Preziosi, R., Prieto, A., Primack, R.B., Ramírez-Angulo, H., Reitsma, J., Réjou-Méchain, M., Correa, Z.R., de Sousa, T.R., Bayona, L.R., Roopsind, A., Rudas, A., Rutishauser, E., Abu Salim, K., Salomão, R.P., Schietti, J., Sheil, D., Silva, R.C., Espejo, J.S., Valeria, C.S., Silveira, M., Simo-Droissart, M., Simon, M.F., Singh, J., Soto Shareva, Y.C., Stahl, C., Stropp, J., Sukri, R., Sunderland, T., Svátek, M., Swaine, M.D., Swamy, V., Taedoumg, H., Talbot, J., Taplin, J., Taylor, D., Ter Steege, H., Terborgh, J., Thomas, R., Thomas, S.C., Torres-Lezama, A., Umunay, P., Gamarra, L.V., van der Heijden, G., van der Hout, P., van der Meer, P., van Nieuwstadt, M., Verbeeck, H., Vernimmen, R., Vicentini, A., Vieira, I.C.G., Torre, E.V., Vleminckx, J., Vos, V., Wang, O., White, L.J.T., Willcock, S., Woods, J.T., Wortel, V., Young, K., Zagt, R., Zemagho, L., Zuidema, P.A., Zwerts, J.A., Phillips, O.L., Sullivan, M.J.P., Lewis, S.L., Affum-Baffoe, K., Castilho, C., Costa, F., Sanchez, A.C., Ewango, C.E.N., Hubau, W., Marimon, B., Monteagudo-Mendoza, A., Qie, L., Sonké, B., Martinez, R.V., Baker, T.R., Brienen, R.J.W., Feldpausch, T.R., Galbraith, D., Gloor, M., Malhi, Y., Aiba, S.-I., Alexiades, M.N., Almeida, E.C., de Oliveira, E.A., Dávila, E.Á., Loayza, P.A., Andrade, A., Vieira, S.A., Aragão, L.E.O.C., Araujo-Murakami, A., Arets, E.J.M.M., Arroyo, L., Ashton, P., Aymard C, G., Baccaro, F.B., Banin, L.F., Baraloto, C., Camargo, P.B., Barlow, J., Barroso, J., Bastin, J.-F., Batterman, S.A., Beeckman, H., Begne, S.K., Bennett, A.C., Berenguer, E., Berry, N., Blanc, L., Boeckx, P., Bogaert, J., Bonal, D., Bongers, F., Bradford, M., Brearley, F.Q., Brncic, T., Brown, F., Burban, B., Camargo, J.L., Castro, W., Céron, C., Ribeiro, S.C., Moscoso, V.C., Chave, J., Chezeaux, E., Clark, C.J., de Souza, F.C., Collins, M., Comiskey, J.A., Valverde, F.C., Medina, M.C., da Costa, L., Dančák, M., Dargie, G.C., Davies, S., Cardozo, N.D., de Haulleville, T., de Medeiros, M.B., Del Aguila Pasquel, J., Derroire, G., Di Fiore, A., Doucet, J.-L., Dourdain, A., Droissant, V., Duque, L.F., Ekoungoulou, R., Elias, F., Erwin, T., Esquivel-Muelbert, A., Fauset, S., Ferreira, J., Llampazo, G.F., Foli, E., Ford, A., Gilpin, M., Hall, J.S., Hamer, K.C., Hamilton, A.C., Harris, D.J., Hart, T.B., Hédl, R., Herault, B., Herrera, R., Higuchi, N., Hladik, A., Coronado, E.H., Huamantupa-Chuquimaco, I., Huasco, W.H., Jeffery, K.J., Jimenez-Rojas, E., Kalamandeen, M., Djuikouo, M.N.K., Kearsley, E., Umetsu, R.K., Kho, L.K., Killeen, T., Kitayama, K., Klitgaard, B., Koch, A., Labrière, N., Laurance, W., Laurance, S., Leal, M.E., Levesley, A., Lima, A.J.N., Lisingo, J., Lopes, A.P., Lopez-Gonzalez, G., Lovejoy, T., Lovett, J.C., Lowe, R., Magnusson, W.E., Malumbres-Olarte, J., Manzatto, ÂG., Marimon B.H., Jr, Marshall, A.R., Marthews, T., de Almeida Reis, S.M., Maycock, C., Melgaço, K., Mendoza, C., Metali, F., Mihindou, V., Milliken, W., Mitchard, E.T.A., Morandi, P.S., Mossman, H.L., Nagy, L., Nascimento, H., Neill, D., Nilus, R., Vargas, P.N., Palacios, W., Camacho, N.P., Peacock, J., Pendry, C., Peñuela Mora, M.C., Pickavance, G.C., Pipoly, J., Pitman, N., Playfair, M., Poorter, L., Poulsen, J.R., Poulsen, A.D., Preziosi, R., Prieto, A., Primack, R.B., Ramírez-Angulo, H., Reitsma, J., Réjou-Méchain, M., Correa, Z.R., de Sousa, T.R., Bayona, L.R., Roopsind, A., Rudas, A., Rutishauser, E., Abu Salim, K., Salomão, R.P., Schietti, J., Sheil, D., Silva, R.C., Espejo, J.S., Valeria, C.S., Silveira, M., Simo-Droissart, M., Simon, M.F., Singh, J., Soto Shareva, Y.C., Stahl, C., Stropp, J., Sukri, R., Sunderland, T., Svátek, M., Swaine, M.D., Swamy, V., Taedoumg, H., Talbot, J., Taplin, J., Taylor, D., Ter Steege, H., Terborgh, J., Thomas, R., Thomas, S.C., Torres-Lezama, A., Umunay, P., Gamarra, L.V., van der Heijden, G., van der Hout, P., van der Meer, P., van Nieuwstadt, M., Verbeeck, H., Vernimmen, R., Vicentini, A., Vieira, I.C.G., Torre, E.V., Vleminckx, J., Vos, V., Wang, O., White, L.J.T., Willcock, S., Woods, J.T., Wortel, V., Young, K., Zagt, R., Zemagho, L., Zuidema, P.A., Zwerts, J.A., and Phillips, O.L.

Abstract

The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (-9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth's climate.

Published
2020

12. The Forest Observation System, building a global reference dataset for remote sensing of forest biomass [data paper]

Author

Schepaschenko, D., Chave, J., Phillips, O. L., Lewis, S. L., Davies, S. J., Réjou-Méchain, Maxime, Sist, P., Scipal, K., Perger, C., Herault, B., Labriere, N., Hofhansl, F., Affum-Baffoe, K., Aleinikov, A., Alonso, A., Amani, C., Araujo-Murakami, A., Armston, J., Arroyo, L., Ascarrunz, N., Azevedo, C., Baker, T., Balazy, R., Bedeau, C., Berry, N., Bilous, A. M., Bilous, S. Y., Bissiengou, P., Blanc, L., Bobkova, K. S., Braslavskaya, T., Brienen, R., Burslem, Dfrp, Condit, R., Cuni-Sanchez, A., Danilina, D., Torres, D. D., Derroire, G., Descroix, L., Sotta, E. D., d'Oliveira, M. V. N., Dresel, C., Erwin, T., Evdokimenko, M. D., Falck, J., Feldpausch, T. R., Foli, E. G., Foster, R., Fritz, S., Garcia-Abril, A. D., Gornov, A., Gornova, M., Gothard-Bassebe, E., Gourlet-Fleury, S., Guedes, M., Hamer, K. C., Susanty, F. H., Higuchi, N., Coronado, E. N. H., Hubau, W., Hubbell, S., Ilstedt, U., Ivanov, V. V., Kanashiro, M., Karlsson, A., Karminov, V. N., Killeen, T., Koffi, J. C. K., Konovalova, M., Kraxner, F., Krejza, J., Krisnawati, H., Krivobokov, L. V., Kuznetsov, M. A., Lakyda, I., Lakyda, P. I., Licona, J. C., Lucas, R. M., Lukina, N., Lussetti, D., Malhi, Y., Manzanera, J. A., Marimon, B., Martinez, R. V., Martynenko, O. V., Matsala, M., Matyashuk, R. K., Mazzei, L., Memiaghe, H., Mendoza, C., Mendoza, A. M., Moroziuk, O. V., Mukhortova, L., Musa, S., Nazimova, D. I., Okuda, T., Oliveira, L. C., Ontikov, P. V., Osipov, A. F., Pietsch, S., Playfair, M., Poulsen, J., Radchenko, V. G., Rodney, K., Rozak, A. H., Ruschel, A., Rutishauser, E., See, L., Shchepashchenko, M., Shevchenko, N., Shvidenko, A., Silveira, M., Singh, J., Sonke, B., Souza, C., Sterenczak, K., Stonozhenko, L., Sullivan, M. J. P., Szatniewska, J., Aedoumg, H. T., Ter Steege, H., Tikhonova, E., Toledo, M., Trefilova, O. V., Valbuena, R., Gamarra, L. V., Vasiliev, S., Vedrova, E. F., Verhovets, S. V., Vidal, E., Vladimirova, N. A., Vleminckx, J., Vos, V. A., Vozmitel, F. K., Wanek, W., West, T. A. P., Woell, H., Woods, J. T., Wortel, V., Yamada, T., Hajar, Z. S. N., and Zo-Bi, I. C.

Abstract

Forest biomass is an essential indicator for monitoring the Earth's ecosystems and climate. It is a critical input to greenhouse gas accounting, estimation of carbon losses and forest degradation, assessment of renewable energy potential, and for developing climate change mitigation policies such as REDD+, among others. Wall-to-wall mapping of aboveground biomass (AGB) is now possible with satellite remote sensing (RS). However, RS methods require extant, up-to-date, reliable, representative and comparable in situ data for calibration and validation. Here, we present the Forest Observation System (FOS) initiative, an international cooperation to establish and maintain a global in situ forest biomass database. AGB and canopy height estimates with their associated uncertainties are derived at a 0.25 ha scale from field measurements made in permanent research plots across the world's forests. All plot estimates are geolocated and have a size that allows for direct comparison with many RS measurements. The FOS offers the potential to improve the accuracy of RS- based biomass products while developing new synergies between the RS and ground-based ecosystem research communities.

Published
2019

16. Field methods for sampling tree height for tropical forest biomass estimation

Author

Sullivan, MJP, Lewis, SL, Hubau, W, Qie, L, Baker, TR, Banin, LF, Chave, J, Sanchez, AC, Feldpausch, T, Lopez Gonzalez, G, Arets, E, Ashton, P, Bastin, JF, Berry, NJ, Bogaert, J, Boot, R, Brearley, FQ, Brienen, R, Burslem, DFRP, de Canniere, C, Chudomelová, M, Dančák, M, Ewango, C, Hédl, R, Lloyd, J, Makana, J-R, Malhi, Y, Marimon, BS, Marimon Junior, BH, Metali, F, Moore, S, Nagy, L, Vargas, PN, Pendry, C, Ramírez-Angulo, H, Reitsma, J, Rutishauser, E, Salim, KA, Sonké, B, Sukri, RS, Sunderland, T, Svátek, M, Umunay, PM, Vasquez Martinez, R, Vernimmen, RRE, Vilanova Torre, E, Vleminckx, J, Vos, V, and Phillips, OL

Subjects
Allometry, Sample size, ALLOMETRIC MODELS, DIAMETER, Above-ground biomass estimation, Ecology and Environment, Carbon stocks, Forest structure, Earth and Environmental Sciences, MAP, Vegetatie, Bos- en Landschapsecologie, Vegetation, Forest and Landscape Ecology, EQUATIONS, ABOVEGROUND BIOMASS, Forest inventory
Abstract

© 2018 The Authors. Methods in Ecology and Evolution published by John Wiley & Sons Ltd on behalf of British Ecological Society. Quantifying the relationship between tree diameter and height is a key component of efforts to estimate biomass and carbon stocks in tropical forests. Although substantial site-to-site variation in height–diameter allometries has been documented, the time consuming nature of measuring all tree heights in an inventory plot means that most studies do not include height, or else use generic pan-tropical or regional allometric equations to estimate height. Using a pan-tropical dataset of 73 plots where at least 150 trees had in-field ground-based height measurements, we examined how the number of trees sampled affects the performance of locally derived height–diameter allometries, and evaluated the performance of different methods for sampling trees for height measurement. Using cross-validation, we found that allometries constructed with just 20 locally measured values could often predict tree height with lower error than regional or climate-based allometries (mean reduction in prediction error = 0.46 m). The predictive performance of locally derived allometries improved with sample size, but with diminishing returns in performance gains when more than 40 trees were sampled. Estimates of stand-level biomass produced using local allometries to estimate tree height show no over- or under-estimation bias when compared with biomass estimates using field measured heights. We evaluated five strategies to sample trees for height measurement, and found that sampling strategies that included measuring the heights of the ten largest diameter trees in a plot outperformed (in terms of resulting in local height–diameter models with low height prediction error) entirely random or diameter size-class stratified approaches. Our results indicate that even limited sampling of heights can be used to refine height–diameter allometries. We recommend aiming for a conservative threshold of sampling 50 trees per location for height measurement, and including the ten trees with the largest diameter in this sample.

Published
2018

17. Effects of etorphine and succinyldicholine on blood composition in elephant and buffalo

Author

Hattingh, J, Wright, P.G., de Vos, V, Levine, Leonora, Ganhao, Maria, McNairn, I.S., Russell, Anthea, Knox, Caroline, Cornelius, S.T., and Bar-Noy, J

Abstract

Blood composition was investigated in anaesthetized elephant and Buffalo and in elephant immobilized by succinyldicholine. Results obtained indicate that data from undisturbed animals shot in the brain closely approximate the situation in anaesthetized animals, except for blood-gas composition. Cortisol concentrations increase after anaesthetization and then decrease again, suggesting that the procedures involved are experienced to some extent as physiological stress. In the case of animals paralysed by succinyldicholine, Cortisol and blood-gets results suggest that when this substance is used in culling procedures, elephant should be killed by a shot into the brain within 16 min after darting.

Published
2017

20. Variation in stem mortality rates determines patterns of aboveground biomass in Amazonian forests: implications for dynamic global vegetation models

Author

Johnson, M O, Galbraith, D, Gloor, E, De Deurwaerder, H, Guimberteau, M, Rammig, A, Thonicke, K, Verbeeck, H, von Randow, C, Monteagudo, A, Phillips, O L, Brienen, R J W, Feldpausch, T R, Lopez Gonzalez, G, Fauset, S, Quesada, C A, Christoffersen, B, Ciais, P, Gilvan, S, Kruijt, B, Meir, P, Moorcroft, P, Zhang, K, Alvarez, E A, Alves de Oliveira, A, Amaral, I, Andrade, A, Aragao, L E O C, Araujo-Murakami, A, Arets, E J M M, Arroyo, L, Aymard, G A, Baraloto, C, Barroso, J, Bonal, D, Boot, R, Camargo, J, Chave, J, Cogollo, A, Cornejo, F Valverde, Costa, L da, di Fiore, A, Ferreira, L, Higuchi, N, Honorio, E, Killeen, T J, Laurance, S G, Laurance, W F, Licona, J, Lovejoy, T, Malhi, Y, Marimon, B, Marimon, B H Junior, Matos, D C L, Mendoza, C, Neill, D A, Pardo, G, Peña-Claros, M, Pitman, N C A, Poorter, L, Prieto, A, Ramirez-Angulo, H, Roopsind, A, Rudas, A, Salomao, R P, Silveira, M, Stropp, J, Ter Steege, H, Terborgh, J, Thomas, R, Toledo, M, Torres-Lezama, A, van der Heijden, Geertje, Vasquez, R, Vieira, I, Vilanova, E, Vos, V A, Baker, T R, Johnson, M O, Galbraith, D, Gloor, E, De Deurwaerder, H, Guimberteau, M, Rammig, A, Thonicke, K, Verbeeck, H, von Randow, C, Monteagudo, A, Phillips, O L, Brienen, R J W, Feldpausch, T R, Lopez Gonzalez, G, Fauset, S, Quesada, C A, Christoffersen, B, Ciais, P, Gilvan, S, Kruijt, B, Meir, P, Moorcroft, P, Zhang, K, Alvarez, E A, Alves de Oliveira, A, Amaral, I, Andrade, A, Aragao, L E O C, Araujo-Murakami, A, Arets, E J M M, Arroyo, L, Aymard, G A, Baraloto, C, Barroso, J, Bonal, D, Boot, R, Camargo, J, Chave, J, Cogollo, A, Cornejo, F Valverde, Costa, L da, di Fiore, A, Ferreira, L, Higuchi, N, Honorio, E, Killeen, T J, Laurance, S G, Laurance, W F, Licona, J, Lovejoy, T, Malhi, Y, Marimon, B, Marimon, B H Junior, Matos, D C L, Mendoza, C, Neill, D A, Pardo, G, Peña-Claros, M, Pitman, N C A, Poorter, L, Prieto, A, Ramirez-Angulo, H, Roopsind, A, Rudas, A, Salomao, R P, Silveira, M, Stropp, J, Ter Steege, H, Terborgh, J, Thomas, R, Toledo, M, Torres-Lezama, A, van der Heijden, Geertje, Vasquez, R, Vieira, I, Vilanova, E, Vos, V A, and Baker, T R

Abstract

Understanding the processes that determine aboveground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity (woody NPP) and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size-structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influence AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates, and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP, and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs. This article is protected by copyright. All rights reserved.

Published
2016

21. Amazon forest response to repeated droughts

Author

Feldpausch, T. R., primary, Phillips, O. L., additional, Brienen, R. J. W., additional, Gloor, E., additional, Lloyd, J., additional, Lopez‐Gonzalez, G., additional, Monteagudo‐Mendoza, A., additional, Malhi, Y., additional, Alarcón, A., additional, Álvarez Dávila, E., additional, Alvarez‐Loayza, P., additional, Andrade, A., additional, Aragao, L. E. O. C., additional, Arroyo, L., additional, Aymard C., G. A., additional, Baker, T. R., additional, Baraloto, C., additional, Barroso, J., additional, Bonal, D., additional, Castro, W., additional, Chama, V., additional, Chave, J., additional, Domingues, T. F., additional, Fauset, S., additional, Groot, N., additional, Honorio Coronado, E., additional, Laurance, S., additional, Laurance, W. F., additional, Lewis, S. L., additional, Licona, J. C., additional, Marimon, B. S., additional, Marimon‐Junior, B. H., additional, Mendoza Bautista, C., additional, Neill, D. A., additional, Oliveira, E. A., additional, Oliveira dos Santos, C., additional, Pallqui Camacho, N. C., additional, Pardo‐Molina, G., additional, Prieto, A., additional, Quesada, C. A., additional, Ramírez, F., additional, Ramírez‐Angulo, H., additional, Réjou‐Méchain, M., additional, Rudas, A., additional, Saiz, G., additional, Salomão, R. P., additional, Silva‐Espejo, J. E., additional, Silveira, M., additional, ter Steege, H., additional, Stropp, J., additional, Terborgh, J., additional, Thomas‐Caesar, R., additional, van der Heijden, G. M. F., additional, Vásquez Martinez, R., additional, Vilanova, E., additional, and Vos, V. A., additional

Published
2016
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23. A produçao familiar como alternativa de um desenvolvimento sustentável para a Amazônia; Liçoes aprendidas de iniciativas de uso florestal por produtores familiares na Amazônia boliviana, brasileira, equatoriana e peruana

Author

Pokorny, B., Godar, J., Hoch, L., Johnson, J., de Koning, J., Medina, G., Steinbrenner, R., Vos, V., and Weigelt, J.

Subjects
Life Science, Bos- en Natuurbeleid, WASS, Forest and Nature Conservation Policy
Abstract

Between 2005 and 2009, the EU-financed project ForLive set out to analyse promising local forest management initiatives in the Amazon Basin in four countries: Ecuador, Bolivia, Brazil, and Peru. Researchers aimed to identify locally viable practices that benefit livelihoods and ecological stabilisation of landscapes, as well as to define ways to promote these practices as a basis for sound rural development. This book presents lessons learnt from more than 100 studies by researchersfrom Latin America, from practitioners and from local families themselves. The findings suggest that the focus of current development strategies designed to support smallholders in adopting management and organization, which are usually externally defined systems made from expert-driven policy and research, mayrequire a review of fundamental assumptions and methods. Most of these initiatives widely ignored the immense potential of Amazonian smallholders—settlers, traditional communities and indigenous groups—to contribute to sound rural development with their own ideas and knowledge. Strong evidence was found that the socio-productive systems of Amazonian smallholders could serve as a reference for new methods that support a more equitable and environmentallysustainable development of the region.

Published
2010

25. Hyperdominance in the Amazonian tree flora

Author

Steege, H. ter, Pitman, C.A., Sabatier, D., Baraloto, C., Salomão, R.P., Guevara, J.E., Phillips, O.L., Castilho, C.V., Magnusson, W.E., Mollino, J.-F., Stevenson Diaz, P.R., Costa , F., Emilio, T., Levis, C., Schietti, J., Souza, P., Alonso, A., Dallmeier, F., Duque Montoya, A.J., Fernandez Piedade, M.T., Maas, P., Araujo-Murakami, A., Arroyo, L., Gribel, R., Fine, P.V.A., Peres, C.A., Toledo, M., Aymard C., G.A., Baker, T.R., Cerón, C., Engel, J., Petronelli, P., Henkel, T.W., Stropp, J., Zartman, C.E., Daly, D., Neill, D., Silveira, M., Ríos Paredes, M., Chave, J., de Andrade Lima Filho, D., Hoffman, B., Møller Jørgensen, P., Fuentes, A., Schöngart, J., Cornejo Valverde, F., Di Fiore, A., Jimenez, E.M., Peñuela Mora, M.C., Phillips, J.F., Rivas, G., Andel, T.R. (Tinde) van, Zent, E.L., Hildebrand, P. von, Malhi, Y., Prieto, A., Rudas, A., Ruschell, A., Silva, N., Vos, V., Zent, S., Oliveira, A.A., Wang, O., Cano Schutz, A., Gonzales, T., Trindade Nascimento, M., Ramirez-Angulo, H., Sierra, R., Tirado , M., Umaña Medina, M.N., Heijden, G. van der, Vela, C.I.A., Vilanova Torre, E., Young, K.R., Vriesendorp, C., Baider, C., Balslev, H., Ferreira, C., Mesones, I., Torres-Lezama, A., Urrego Giraldo, L.E., Zagt, R., Alexiades, M.N., Monteagudo, A., Hernandez, L., Huamantupa-Chuquimaco, I., Millikes, W., Palacios Cuenca, W., Pauletto, D., Valderrama Sandoval, E., Valenzuela Gamarra, L., Dexter, K.G., Feeley, K., Lopez-Gonzalez, G., Núñez Vargas, P., Silman, M.R., Montero, J.C., Feldpausch, T.R., Honorio Coronado, E.N., Killeen, T.J., Mostacedo, B., Vasquez, R., Assis, R.L., Terborgh, J., Wittmann, F., Andrade, A., Laurance, W.F., Laurance, S.G.W., Marimon, B.S., Marimon , (B.-H. Jr.), Célia Guimarães Vieira, I., Leão Amaral, I., Brienen, R., Castellanos, H., Cárdenas López, D., Duivenvoorden, J.F., Mogollón, H.F., Dionízia de Almeida Matos, F., Dávila, N., García-Villacorta, R., Steege, H. ter, Pitman, C.A., Sabatier, D., Baraloto, C., Salomão, R.P., Guevara, J.E., Phillips, O.L., Castilho, C.V., Magnusson, W.E., Mollino, J.-F., Stevenson Diaz, P.R., Costa , F., Emilio, T., Levis, C., Schietti, J., Souza, P., Alonso, A., Dallmeier, F., Duque Montoya, A.J., Fernandez Piedade, M.T., Maas, P., Araujo-Murakami, A., Arroyo, L., Gribel, R., Fine, P.V.A., Peres, C.A., Toledo, M., Aymard C., G.A., Baker, T.R., Cerón, C., Engel, J., Petronelli, P., Henkel, T.W., Stropp, J., Zartman, C.E., Daly, D., Neill, D., Silveira, M., Ríos Paredes, M., Chave, J., de Andrade Lima Filho, D., Hoffman, B., Møller Jørgensen, P., Fuentes, A., Schöngart, J., Cornejo Valverde, F., Di Fiore, A., Jimenez, E.M., Peñuela Mora, M.C., Phillips, J.F., Rivas, G., Andel, T.R. (Tinde) van, Zent, E.L., Hildebrand, P. von, Malhi, Y., Prieto, A., Rudas, A., Ruschell, A., Silva, N., Vos, V., Zent, S., Oliveira, A.A., Wang, O., Cano Schutz, A., Gonzales, T., Trindade Nascimento, M., Ramirez-Angulo, H., Sierra, R., Tirado , M., Umaña Medina, M.N., Heijden, G. van der, Vela, C.I.A., Vilanova Torre, E., Young, K.R., Vriesendorp, C., Baider, C., Balslev, H., Ferreira, C., Mesones, I., Torres-Lezama, A., Urrego Giraldo, L.E., Zagt, R., Alexiades, M.N., Monteagudo, A., Hernandez, L., Huamantupa-Chuquimaco, I., Millikes, W., Palacios Cuenca, W., Pauletto, D., Valderrama Sandoval, E., Valenzuela Gamarra, L., Dexter, K.G., Feeley, K., Lopez-Gonzalez, G., Núñez Vargas, P., Silman, M.R., Montero, J.C., Feldpausch, T.R., Honorio Coronado, E.N., Killeen, T.J., Mostacedo, B., Vasquez, R., Assis, R.L., Terborgh, J., Wittmann, F., Andrade, A., Laurance, W.F., Laurance, S.G.W., Marimon, B.S., Marimon , (B.-H. Jr.), Célia Guimarães Vieira, I., Leão Amaral, I., Brienen, R., Castellanos, H., Cárdenas López, D., Duivenvoorden, J.F., Mogollón, H.F., Dionízia de Almeida Matos, F., Dávila, N., and García-Villacorta, R.

Abstract

The vast extent of the Amazon Basin has historically restricted the study of its tree communities to the local and regional scales. Here, we provide empirical data on the commonness, rarity, and richness of lowland tree species across the entire Amazon Basin and Guiana Shield (Amazonia), collected in 1170 tree plots in all major forest types. Extrapolations suggest that Amazonia harbors roughly 16,000 tree species, of which just 227 (1.4%) account for half of all trees. Most of these are habitat specialists and only dominant in one or two regions of the basin. We discuss some implications of the finding that a small group of species—less diverse than the North American tree flora—accounts for half of the world’s most diverse tree community.

Published
2013
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26. Tree height integrated into pantropical forest biomass estimates

Author

Feldpausch, Ted R., Lloyd, J., Lewis, Simon L., Brienen, R.J.W., Gloor, M., Monteagudo Mendoza, A., Lopez Gonzalez, G., Banin, L., Abu Salim, K., Affum-Baffoe, K., Alexiades, M., Almeida, S., Amaral, Ieda, Andrade, Ana, Aragao, Luiz, Araujo Murakami, A., Arets, E.J.M.M., Arroyo, L., Aymard, Gerardo, Baker, T.R. de, Banki, Olaf, Berry, N. J., Cardozo, N., Jerome, Chave, Comiskey, J. A., Alvarez, E., de Oliveira, A., Di Fiore, A., Djagbletey, G., Domingues, T.F., Erwin, T., Fearnside, P. M., França, M. B., Freitas, M. A., Higuchi, Niro, Honorio C., E., Iida, Y., Jimenez, E., Kassim, A.R., Killeen, T.J., Laurance, W.F., Lovett, Jon C., Malhi, Y., Marimon, B.S., Marimon-Junior, B.H., Lenza, E., Marshall, A.R., Mendoza, Casimiro, Metcalfe, D.J., Mitchard, E.T.A., Neill, D.A., Nelson, B.W., Nilus, R., Nogueira, E.M., Parada, A., Peh, K.S.-H., Peña Cruz, A., Peñuela, M.C., Pitman, N.C.A., Prieto, A., Quesada, C.A., Ramírez, F., Ramirez Angulo, H., Reitsma, J.M., Rudas, A., Saiz, G., Salomao, R. P., Schwarz, M., Silva, N., Silva Espejo, J.E., Silveira, Marcos, Sonke, Bonaventura, Stropp, Juliana, Taedoumg, H. E., Tan, S., Ter Steege, Hans, Terborgh, J., Torello-Raventos, M., Van der Heijden, Geertje, Vasquez, R., Vilanova, Emilio, Vos, V. A., White, L., Willcock, S., Woell, H., Phillip, Oliver L., Feldpausch, Ted R., Lloyd, J., Lewis, Simon L., Brienen, R.J.W., Gloor, M., Monteagudo Mendoza, A., Lopez Gonzalez, G., Banin, L., Abu Salim, K., Affum-Baffoe, K., Alexiades, M., Almeida, S., Amaral, Ieda, Andrade, Ana, Aragao, Luiz, Araujo Murakami, A., Arets, E.J.M.M., Arroyo, L., Aymard, Gerardo, Baker, T.R. de, Banki, Olaf, Berry, N. J., Cardozo, N., Jerome, Chave, Comiskey, J. A., Alvarez, E., de Oliveira, A., Di Fiore, A., Djagbletey, G., Domingues, T.F., Erwin, T., Fearnside, P. M., França, M. B., Freitas, M. A., Higuchi, Niro, Honorio C., E., Iida, Y., Jimenez, E., Kassim, A.R., Killeen, T.J., Laurance, W.F., Lovett, Jon C., Malhi, Y., Marimon, B.S., Marimon-Junior, B.H., Lenza, E., Marshall, A.R., Mendoza, Casimiro, Metcalfe, D.J., Mitchard, E.T.A., Neill, D.A., Nelson, B.W., Nilus, R., Nogueira, E.M., Parada, A., Peh, K.S.-H., Peña Cruz, A., Peñuela, M.C., Pitman, N.C.A., Prieto, A., Quesada, C.A., Ramírez, F., Ramirez Angulo, H., Reitsma, J.M., Rudas, A., Saiz, G., Salomao, R. P., Schwarz, M., Silva, N., Silva Espejo, J.E., Silveira, Marcos, Sonke, Bonaventura, Stropp, Juliana, Taedoumg, H. E., Tan, S., Ter Steege, Hans, Terborgh, J., Torello-Raventos, M., Van der Heijden, Geertje, Vasquez, R., Vilanova, Emilio, Vos, V. A., White, L., Willcock, S., Woell, H., and Phillip, Oliver L.

Abstract

Aboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: 1. What is the best H-model form and geographic unit to include in biomass models to minimise site-level uncertainty in estimates of destructive biomass? 2. To what extent does including H estimates derived in (1) reduce uncertainty in biomass estimates across all 327 plots? 3. What effect does accounting for H have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of destructively harvested trees when including H (mean 0.06), was half that when excluding H (mean 0.13). Power- andWeibull-H models provided the greatest reduction in uncertainty, with regional Weibull-H models preferred because they reduce uncertainty in smaller-diameter classes (?40 cm D) that store about one-third of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows that including H reduces errors from 41.8Mgha?1 (range 6.6 to 112.4) to 8.0Mgha?1 (?2.5 to 23.0). For all plots, aboveground live biomass was ?52.2 Mgha?1 (?82.0 to ?20.3 bootstrapped 95%CI), or 13%, lower when including H estimates, with the greatest relative reductions in estimated biomass in forests of the Brazilian Shield, east Africa, and Australia, and relatively little change in the Guiana Shield, central Africa and southeast Asia. Appreciably different stand structure was observed among regions across the tropical continents, with some storing significantly more biomass in small diameter stems, which affects selection of the best height models to reduce uncertainty and biomass reductions due to H. After accounting for variation in H, total biomass p

Published
2012

27. La producción familiar como alternativa de un desarrollo sostenible para la Amazonía; Lecciones aprendidas de iniciativas de uso forestal por productores familiares en la Amazonía boliviana, brasilera, ecuatoriana y peruana

Author

Pokorny, B., Godar, J., Hoch, L., Johnson, J., de Koning, J., Medina, G., Steinbrenner, R., Vos, V., Weigelt, J., Pokorny, B., Godar, J., Hoch, L., Johnson, J., de Koning, J., Medina, G., Steinbrenner, R., Vos, V., and Weigelt, J.

Abstract

Between 2005 and 2009, the EU-financed project ForLive set out to analyse promising local forest management initiatives in the Amazon Basin in four countries: Ecuador, Bolivia, Brazil, and Peru. Researchers aimed to identify locally viable practices that benefit livelihoods and ecological stabilisation of landscapes, as well as to define ways to promote these practices as a basis for sound rural development. This book presents lessons learnt from more than 100 studies by researchersfrom Latin America, from practitioners and from local families themselves. The findings suggest that the focus of current development strategies designed to support smallholders in adopting management and organization, which are usually externally defined systems made from expert-driven policy and research, mayrequire a review of fundamental assumptions and methods. Most of these initiatives widely ignored the immense potential of Amazonian smallholders—settlers, traditional communities and indigenous groups—to contribute to sound rural development with their own ideas and knowledge. Strong evidence was found that the socio-productive systems of Amazonian smallholders could serve as a reference for new methods that support a more equitable and environmentallysustainable development of the region.

Published
2010

29. Blood constituent responses of animals culled with succinyldicholine and hexamethonium

Author

Hattingh J, Neville Pitts, Mf, Ganhao, Dg, Moyes, and de Vos V

Subjects
Blood Glucose, Catecholamines, Time Factors, Buffaloes, Hydrocortisone, Stress, Physiological, Elephants, Animals, Succinylcholine, Hexamethonium Compounds
Abstract

Blood constituent responses of elephants and buffaloes culled in the Kruger National Park, using a mixture of succinyldicholine and hexamethonium, were compared to those of animals culled with succinyldicholine only. The results show a decreased physiological response in the animals culled with the mixture, characterised by lower total catecholamine, cortisol and glucose concentrations. Neither a delay of up to 30 min in obtaining blood samples from culled animals, nor a delay of up to 30 min in processing samples obtained immediately after cessation of respiration, gave any significant difference in the blood constituents which were measured.

Published
1990

43. Influence of cryoprotective diluent on post-thaw viability and acrosomal integrity of spermatozoa of the African elephant (Loxodonta africana)

Author

Howard, J. G., Bush, M., de Vos, V., Schiewe, M. C., Pursel, V. G., and Wildt, D. E.

Abstract

Summary.Electroejaculates from free-ranging, African elephants were frozen to test various seminal diluents, freezing methods and thawing media on post-thaw sperm viability and structural integrity. In Study I, each ejaculate was tested with each of 7 cryoprotective diluents. After cooling to 5°C and equilibration on ice (4°C) for 120 min, each aliquant was pellet frozen on solid CO2, stored in liquid nitrogen and thawed (37°C) in saline or tissue culture solution. Amongst all diluents, post-thaw sperm motility, motility duration in vitro(37°C) and acrosomal integrity were greatest (P< 0·05) when diluent BF5F was used. Thawing medium had no effect on results. In Study II, the optimal diluent from Study I (BF5F) was compared with the diluent SGI. Results were not affected by a 90- or a 150-min cooling–equilibration interval in an electronic cooler (5°C); however, post-thaw sperm motility rating and duration of motility in vitrowere greater (P<0·01) with the pellet than the straw container freezing method. When the pelleting method was used, diluents BF5F and SGI provided comparable cryoprotection. Duration of post-thaw motility was enhanced 2-fold and up to 12h by maintaining thawed semen at 21 rather than 37°C (P<0·05) All diluents provided some protection on acrosomal integrity, but the overall proportion of intact acrosomes after thawing was markedly less in Study II, apparently as a result of the slower initial cooling rate (∼1·5°C/min) compared to that of Study I (∼6·5°C/min). This study demonstrates the feasibility of cryopreserving semen from free-ranging African elephants and indicates that spermatozoa must effectively survive freezing when the BF5F or SGI diluent is used in conjunction with the pelleting method.

Published
1986
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44. Electroejaculation, semen characteristics and serum testosterone concentrations of free-ranging African elephants (Loxodonta africana)

Author

Howard, JoGayle, Bush, M., de Vos, V., and Wildt, D. E.

Abstract

Summary.A regimented electroejaculation protocol (120 electrical stimulations; 10-30 V) was used to collect semen and characterize ejaculate quality from 9 adult, free-ranging African elephants under anaesthesia. Eight of the 9 ejaculates contained high concentrations of progressively motile spermatozoa. The overall mean ejaculate volume, sperm concentration/ml ejaculate, sperm motility, sperm status and ejaculate pH were 93·3 ml, 2408·6 × 106spermatozoa/ml, 70%, 3·9 and 7·4, respectively. A high percentage (mean 77·5%) of spermatozoa within each ejaculate was morphologically normal. Of the aberrant spermatozoa, 72% had a cytoplasmic droplet defect. When sperm viability was tested in vitroat 37°C, sperm motility rating declined by at least half of the initial assessment within 3·5 h of semen collection. Generally, spermatozoa maintained motility in vitrofor < 6 h. Serum testosterone ranged from 1·4 to 8·2 ng/ml in 4 males evaluated in the morning (07:30–08:00 h). In 4 of the 5 bulls assessed in the afternoon (15:00–18:00 h), testosterone levels were <0·9 ng/ml. The remaining bull, evaluated at 16:00 h, had exceptionally high testosterone concentrations (peak 25·6 ng/ml) and a preputial discharge potentially indicative of 'musth'. The present study demonstrates that high quality semen can be collected consistently from the African elephant and that striking differences exist in serum testosterone amongst free-ranging males which may be due, in part, to a diurnal rhythm.

Published
1984
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45. Where do parents belong in public education?

Author

Vos, V.

Subjects
EDUCATION
Abstract

Argues that only by altering the traditional parent-teacher contacts, and by creating new opportunities to meet, can parents and teachers build a trusting and cooperative relationship. Restoring the lost partnership; Building a cooperative relationship; Parent involvement; For more information.

Published
1992

46. A Survey of Selected Bacteriological Infections of the Chacma Baboon 'Papio ursinus' from the Kruger National Park

Author

ARMED FORCES INST OF PATHOLOGY WASHINGTON DC, Van Niekerk, C. A. W. J., McConnell, E. E., de Vos, V., ARMED FORCES INST OF PATHOLOGY WASHINGTON DC, Van Niekerk, C. A. W. J., McConnell, E. E., and de Vos, V.

Abstract

An absence of bacterial pathogens and zoonoses emerged as the salient feature in a bacteriological survey of chacma baboons from the Kruger National Park. Totals varying from 100 to 178 baboons were assayed for salmonellosis, shigellosis, tuberculosis, brucellosis and leptospirosis. It is conjectured that with Kruger National Park baboons, the above mentioned pathogens are not expected to complicate handling procedures or experimentation, provided a clean or pathogen-free environment is maintained from the day of capture onwards., Pub. in Koedoe, v16 p1-10, 1973.

Published
1973

47. Floristics and biogeography of vegetation in seasonally dry tropical regions

Author

Dexter, K. G., Smart, B., Baldauf, C., Baker, T. R., Balinga, M. P. Bessike, Brienen, R. J. W., Fauset, S., Ted R. Feldpausch, Ferreira-Da Silva, L., Muledi, J. Ilunga, Lewis, S. L., Lopez-Gonzalez, G., Marimon-Junior, B. H., Marimon, B. S., Meerts, P., Page, N., Parthasarathy, N., Phillips, O. L., Sunderland, T. C. H., Theilade, I., Weintritt, J., Affum-Baffoe, K., Araujo, A., Arroyo, L., Begne, S. K., Carvalho-Das Neves, E., Collins, M., Cuni-Sanchez, A., Djuikouo, M. N. K., Elias, F., Foli, E. G., Jeffery, K. J., Killeen, T. J., Malhi, Y., Maracahipes, L., Mendoza, C., Monteagudo-Mendoza, A., Morandi, P., Oliveira-Dos Santos, C., Parada, A. G., Pardo, G., Peh, K. S. -H, Salomao, R. P., Silveira, M., Sinatora-Miranda, H., Slik, J. W. F., Sonke, B., Taedoumg, H. E., Toledo, M., Umetsu, R. K., Villaroel, R. G., Vos, V. A., White, L. J. T., and Pennington, R. T.

Subjects
Tropical and subtropical dry broadleaf forests, Flora, Ecology, Biogeography, Geography, Planning and Development, Tropical vegetation, Tropics, Forestry, Rainforest, Vegetation, Floristics
Abstract

To provide an inter-continental overview of the floristics and biogeography of drought-adapted tropical vegetation formations, we compiled a dataset of inventory plots in South America (n=93), Africa (n=84), and Asia (n=92) from savannas (subject to fire), seasonally dry tropical forests (not generally subject to fire), and moist forests (no fire). We analysed floristic similarity across vegetation formations within and between continents. Our dataset strongly suggests that different formations tend to be strongly clustered floristically by continent, and that among continents, superficially similar vegetation formations (e.g. savannas) are floristically highly dissimilar. Neotropical moist forest, savanna and seasonally dry tropical forest are floristically distinct, but elsewhere there is no clear floristic division of savanna and seasonally dry tropical forest, though moist and dry formations are separate. We suggest that because of their propensity to burn, many formations termed “dry forest” in Africa and Asia are best considered as savannas. The floristic differentiation of similar vegetation formations from different continents suggests that cross-continental generalisations of the ecology, biology and conservation of savannas and seasonally dry tropical forests may be difficult.

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