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The conservation of tropical forests is recognized as one of the most important challenges for forestry, ecology and politics. Besides strict protection, the sustainable management of natural forests should be enhanced as a key part of the foundation for the maintenance of tropical rain forest ecosystems. Due to methodological reasons it has been complicated to attain reliable growth data to plan sustainable felling cycles and rotation periods. Tree ring analyses enable the estimation of growth rates over the entire life span of trees and their age as well as giving hints from forest dynamics in previous centuries. For tree ring analysis, stem disk samples were taken from three important commercial tree species (Cariniana micrantha, Caryocar villosum and Manilkara huberi) in the upland (terra firme) forests of the Precious Woods Amazon logging company near Itacoatiara, Brazil. Based on radiocarbon estimates of individual growth zones, the annual nature of tree rings was proven for the three species. Tree rings were measured and the results used together with height estimates to model diameter, height and volume growth. The age of the eldest tree, a C. micrantha, was 585 yrs with 165 cm in diameter. The species' diameter increments range from 0.20±0.12 cm yr-1 to 0.29±0.08 cm yr-1. At first sight, this is considerably lower than increments reported from other Amazonian or African timber species. Considering the respective wood density there is no significant difference in growth performance of dominant timber species across continents. The interpretation of lifetime tree ring curves indicate differences in shadow tolerance among species, the persistence of individuals in the understory for up to 150 years and natural stand dynamics without major disturbances. Management criteria should be adapted for the measured growth rates as they differed considerably from the Brazilian standards fixed by laws (felling cycle of 25-35 years and a common minimum logging diameter of 50 cm). Felling cycles should be increased to 32-51 years and minimum logging diameters to 63-123 cm depending on the species. ; Open-Access-Publikationsfonds 2019 ; peerReviewed

The conservation of tropical forests is recognized as one of the most important challenges for forestry, ecology and politics. Besides strict protection, the sustainable management of natural forests should be enhanced as a key part of the foundation for the maintenance of tropical rain forest ecosystems. Due to methodological reasons it has been complicated to attain reliable growth data to plan sustainable felling cycles and rotation periods. Tree ring analyses enable the estimation of growth rates over the entire life span of trees and their age as well as giving hints from forest dynamics in previous centuries. For tree ring analysis, stem disk samples were taken from three important commercial tree species (Cariniana micrantha, Caryocar villosum and Manilkara huberi) in the upland (terra firme) forests of the Precious Woods Amazon logging company near Itacoatiara, Brazil. Based on radiocarbon estimates of individual growth zones, the annual nature of tree rings was proven for the three species. Tree rings were measured and the results used together with height estimates to model diameter, height and volume growth. The age of the eldest tree, a C. micrantha, was 585 yrs with 165 cm in diameter. The species' diameter increments range from 0.20±0.12 cm yr-1 to 0.29±0.08 cm yr-1. At first sight, this is considerably lower than increments reported from other Amazonian or African timber species. Considering the respective wood density there is no significant difference in growth performance of dominant timber species across continents. The interpretation of lifetime tree ring curves indicate differences in shadow tolerance among species, the persistence of individuals in the understory for up to 150 years and natural stand dynamics without major disturbances. Management criteria should be adapted for the measured growth rates as they differed considerably from the Brazilian standards fixed by laws (felling cycle of 25–35 years and a common minimum logging diameter of 50 cm). Felling cycles should be increased to 32–51 years and minimum logging diameters to 63–123 cm depending on the species. © 2019 Worbes, Schöngart. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Central Amazonian floodplain forests are an unique and endangered ecosystem. The forests grow in areas that are annually flooded by large rivers during mean periods of up to 8 months and at depths of up to 10 m. Despite this severe stress, these forests consist of over 1,000 species and are by far the most species-rich floodplain forests worldwide. The trees show a broad range of morphological, anatomical, physiological, and phenological adaptations that enable them not only to survive the adverse environmental conditions, but also to produce large amounts of biomass when the nutrient levels in water and soils are sufficiently high. This is the case in the floodplains of white-water rivers, which are used for fisheries, agriculture, and cattle-ranching but which also have a high potential for the production of timber and non-timber products, when adequately managed. Latest research on ecophysiology gives insight how tree species adapt to the oscillating flood-pulse focusing on their photosynthesis, respiration, sap flow, biochemistry, phenology, wood and leave anatomy, root morphology and functioning, fruit chemistry, seed germination, seedling establishment, nitrogen fixation and genetic variability. Based on tree ages, lifetime growth rates and net primary production, new concepts are developed to improve the sustainability of traditional forest managements in the background of an integrated natural resource management. This is the first integrative book on the functioning and ecologically oriented use of floodplain forests in the tropics and sub-tropics.It provides fundamental knowledge for scientist, students, foresters and other professionals on their distribution, evolution and phytogeography. 'This book is an excellent testimony to the interdisciplinary collaboration of a group of very dedicated scientists to unravel the functioning of the Amazonian Floodplain forests. They have brought together a highly valuable contribution on the distribution, ecology, primary production, ecophysiology, typology, biodiversity, and human use of these forests offering recommendations for sustainable management and future projects in science and development of these unique wetland ecosystems. It lays a solid scientific foundation for wetland ecologists, foresters, environmentalists, wetland managers, and all those interested in sustainable management in the tropics and subtropics.' Brij Gopal, Executive Vice President International Society for Limnology (SIL).

The Brazil nut tree (Bertholletia excelsa) is an iconic and economically valuable species that dominates vast swathes of the Amazon Basin. This species seems to have been an important part of human subsistence strategies in the region from at least the Early Holocene, and its current distribution may be a legacy of past human settlement. Because B. excelsa is a long-lived pioneer tree it requires natural or human disturbances to increase light availability in the understory for a successful establishment. However, it remains unclear how the long-term population dynamics of this species have been shaped by pre-colonial and post-colonial human practices. Here, we use tree-ring analyses to look at changes in growing conditions over the past 400 years in a Brazil nut tree population in Central Amazonia. We identify changes in tree recruitment and growth rates associated not only with regional climatic variability, but also major political and socio-economic activities recorded by historical documents in the vicinity of Manaus. We demonstrate that the expansion of a post-colonial political center (Manaus) from the middle of the 18 th century onwards coincided with a reduction in recruitment of B. excelsa. We argue that this hiatus suggests the interruption of indigenous management practices, probably due to the collapse of pre-Columbian societies. A second recruitment pulse, and unprecedented cycles of growth release and suppression, aligns with a shift to modern exploitation of the forest into the 20 th century. Our findings shed light on how past histories of human-forest interactions can be revealed by the growth rings of trees in Amazonia. Future interdisciplinary analysis of these trees should enable more detailed investigation of how human forest management has changed in this part of the world, through pre-colonial, colonial, and industrial periods of human activity, with potential implications for conservation. © 2019 Caetano Andrade et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This paper is the result of the work of hundreds of different scientists and research institutions in the Amazon over the past 80 years. Without their hard work this analysis would have been impossible. We thank Charles Zartman for the use of plots from Jutai. HtS, VFG, and RS were supported by grant 407232/2013-3 - PVE - MEC/MCTI/CAPES/CNPq/FAPs; PIP had support for this work from CNPq (productivity grant 310885/2017-5) and FAPESP (research grant #09/53413-5); RAFL was supported by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 795114; CB was supported by grant FAPESP 95/3058-0 - CRS 068/96 WWF Brasil - The Body Shop; DS, JFM, JE, PP and JC benefited from an "Investissement d'Avenir" grant managed by the Agence Nationale de la Recherche (CEBA: ANR-10-LABX-25-01); HLQ/MAP/JLLM received financial supported by MCT/CNPq/CT-INFRA/GEOMA #550373/2010-1 and # 457515/2012-0, and JLLM were supported by grant CAPES/PDSE # 88881.135761/2016-01 and CAPES/Fapespa #1530801; The Brazilian National Research Council (CNPq) provided a productivity grant to EMV (Grant 308040/2017-1); Floristic identification in plots in the RAINFOR forest monitoring network have been supported by the Natural Environment Research Council (grants NE/B503384/1, NE/ D01025X/1, NE/ I02982X/1, NE/F005806/1, NE/D005590/1 and NE/I028122/1) and the Gordon and Betty Moore Foundation; BMF is funded by FAPESP grant 2016/25086-3. BSM, BHMJ and OLP were supported by grants CNPq/CAPES/ FAPS/BC-Newton Fund #441244/2016-5 and FAPEMAT/0589267/2016; TWH was funded by National Science Foundation grant DEB-1556338.The 25-ha Long-Term Ecological Research Project of Amacayacu is a collaborative project of the Instituto Amazónico de Investigaciones Científicas Sinchi and the Universidad Nacional de Colombia Sede Medellín, in partnership with the Unidad de Manejo Especial de Parques Naturales Nacionales and the Center for Tropical Forest Science of the Smithsonian Tropical Research Institute (CTFS). The Amacayacu Forest Dynamics Plot is part of the Center for Tropical Forest Science, a global network of large-scale demographic tree plots. We acknowledge the Director and staff of the Amacayacu National Park for supporting and maintaining the project in this National Park. ; Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals, where aggregation increases with rarity. By averaging several methods to estimate total richness, we confirm that over 15,000 tree species are expected to occur in Amazonia. We also show that using ten times the number of plots would result in an increase to just ~50% of those 15,000 estimated species. To get a more complete sample of all tree species, rigorous field campaigns may be needed but the number of trees in Amazonia will remain an estimate for years to come. ; Publisher PDF ; Peer reviewed