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Abstract: Linked Open Science is an approach to solve challenges of an executable paper. It is a combination of four “silver bullets”: 1) publication of scientific data, metadata, results, and provenance information using Linked Data principles, 2) open source and web-based environments for executing, validating and exploring research, 3) Cloud Computing for effcient and distributed computing, and 4) Creative Commons for the legal infrastructure. We will use a realistic scientific research setting related to research on deforestation of the Brazilian Amazon rainforest to provide scenarios to illustrate the application of Linked Open Science. [Copyright &y& Elsevier]

Looking beyond a normative analysis of oil palm expansion, this paper offers a nuanced analysis of landscape transformations in the Brazilian Amazonian region of Tomé-Açu. Based on quantitative and qualitative data deriving from interviews with key stakeholders, focus groups and surveys with smallholders and migrant workers, contextualized and cross-checked with observations between 2011 and 2017 and secondary sources, we discuss the processes and outcomes of Brazil's Sustainable Oil Palm Production Program (SPOPP). Despite its participatory component and innovative design, simultaneously tackling environmental, economic and social dimensions, the program underwent rapid structural change and suffered from discontinuity. A new boom and bust cycle emerged in the region, however, both "boom" and "bust" periods were marked by mixed outcomes. Notwithstanding the current governance shift characterized by absent state, reduced participation and disinvestment, local agency has been able to reorganize the sector on the ground and a transformed landscape emerged. However, under the current setting if expansion recommences there is no guarantee the sector will be able to avoid many of the socio-environmental problems experienced in the past. • SPOPP is an example of the emergence of participatory governance modes in the Brazilian Amazon. • SPOPP triggered a new boom and bust cycle in the researched region. • Outcomes of both cycles were mixed, from euphoria and criticism to disenchantment and reorganization. • Despite state withdrawal and reduced participatory governance the sector reconfigured under local and global drivers. • If expansion recommences there are several socio-environmental risks under the current governance shift. [ABSTRACT FROM AUTHOR]

• SWAF-HR data is new water surface extent product at 1 km over the Amazon basin from 2010 to 2016 every 3 days. • SWAF-HR provided from the fusion of three datasets: water surface fraction at coarse spatial resolution from an L-band passive microwave sensor (Soil Moisture and Ocean Salinity – SMOS), Global Surface Water Occurrence from Landsat (GSWO) and the Digital Elevation Model (DEM) Multi-Error-Removed-Terrain (MERIT) based on the Shuttle Radar Topography Mission. • The flooded area of the Branco floodplain (Roraima) varies from 0.2 times 104 to 2.7 × 104 km2 whereas the extent of the Bolivian floodplain (Llanos de Moxos) inundation ranges between 0.8 × 104 and 8.1 × 104 km2 during 2010–2016. • The choice of the DEM in the downscaling process introduces 5% of error in the instantaneous water surface extent estimate but can reach up to 10% in the flood probability estimations over seven years. • (MERIT) based on the Shuttle Radar Topography Mission (SRTM). In this paper, we present a methodology to map inland water in tropical areas under dense vegetation at high spatial and temporal resolution using multi-source remote sensing data. A new inundation product (SWAF-HR) is presented. It is characterized by a high spatial resolution (30′, 1 km) and high temporal resolution (3 days). The SWAF-HR product is estimated over the Amazon basin for the 2010–2016 period. It is based on a downscaling procedure and the synergistic use of: (1) water surface fraction at coarse spatial resolution from an L-band passive microwave sensor (Soil Moisture and Ocean Salinity – SMOS), (2) Global Surface Water Occurrence from Landsat (GSWO) and (3) the Digital Elevation Model (DEM) Multi-Error-Removed-Improved-Terrain (MERIT) based on the Shuttle Radar Topography Mission (SRTM). Thanks to the high capability of L-band microwave emission to reveal surface water under all-weather conditions and beneath the vegetation, the inundated area extent estimated by the SWAF-HR product is always larger than GSWO estimates obtained by the optical sensor (Landsat). SWAF-HR data is compared to ESA CCI and IGBP land covers, two SAR images and flooded areas over the Purus basin computed by the MGB-IPH model simulation. The results show the coherence of spatial and temporal dynamics of the SWAF-HR data. We show that the flooded area of the Branco River floodplain in Roraima (Brazil) varies from 0.2 × 104 to 2.7 × 104 km2 whereas the extent of the Bolivian floodplain (Llanos de Moxos) inundation ranges between 0.8 × 104 and 8.1 × 104 km2 during 2010–2016. The flooded area in the Branco floodplain gradually decreased from 2010 to 2015 but in 2016, the flooded area has increased during the rainy season. During 2010–2016, the minimum of the inundated surface extent was reached during 2015–2016 reflecting to a drought event related to ENSO. The most important uncertainties of the DEM are located over tropical areas but this information is essential in the downscaling procedure. Therefore, we investigate the impact of the choice of the DEM for the downscaling procedure. It is found that the choice of the DEM introduces 5% of error in the instantaneous water surface extent estimate but can reach up to 10% in the flood probability estimations over seven years. This new SWAF-HR product will be helpful for the understanding of the water, carbon and biogeochemical cycles of the Amazon. [ABSTRACT FROM AUTHOR]

Abstract: The conventional understanding of environmental governance implicitly assumes a priori presence of citizen rationality that underpins constitution of civil society vis-à-vis state. This assumption tends to overlook the economic and ecological consequences of social interactions through which people with diverse forms of rationality gradually produce distinction between state and society and shape environmental governance as an embedded process. This paper presents a case study of spontaneous settlers called posseiros in the south-east of the state of Pará in the Brazilian Amazon and examines ways that their social interactions lead to the so-called emancipation movements for municipal making on the agrarian frontier and open civic places in which environmental governance is negotiated. It pays particular attention to the role of religion, especially the Pentecostal Church of Assembly of God in relation to the traditional Catholic Church, in influencing the posseiros' ecological rationality and the articulation of emancipation movements and argues that the focus on religion sheds new light on the linkage between the environment, livelihoods and local governance. The paper concludes by discussing pragmatic implications of the case study for promoting sustainable rural development. [Copyright &y& Elsevier]

Abstract: Over the last decades, hundreds of thousands of families have settled in the Brazilian Amazon within the framework of the Agrarian Reform Program (ARP). The rationale behind the program is to enable settlers to earn their living by small-scale farming and producing an agricultural surplus for the market. This paper aims to analyze the settlers' livelihood strategies under the framework of the ARP and its objectives. The paper considers more than just land use shares. Income composition, capital (human, physical, natural, social, and financial), mediating process, and context are also included, and these reveal three groups of livelihood strategies. Most of the settlers have achieved the ARP goals, mainly by deploying livestock strategies, particularly milk production. [Copyright &y& Elsevier]

The Amazon forest in the state of Maranhão ensures ecosystem services that directly and indirectly affect the life quality of its population and economy, via hydrologic and climatic regulation, among other benefits. Currently, only 25% of the original forest cover (24.7 thousand km 2 ) remains while illegal deforestation persists in a violent process that provokes visible social, economic and environmental harm. Simultaneously, Maranhão has seen record levels of burning, faces a water shortage and fights against the worst social and economic indicators in the country. Conversely, secondary vegetation covers 19.9 thousand km 2 (27% of deforested area) and is completely unprotected. Contrary to the international commitments assumed by Brazil to combat deforestation and restore forests, some of the political representatives of Maranhão have sought legal mechanisms to further diminish forest cover in public and private areas. To promote the conservation and restoration of Maranhão Amazon Forest, a multi-institutional network of researchers was established in 2015. This viewpoint paper aims to draw attention to this endangered region of the Brazilian Amazon and give science-oriented recommendations to policy makers in order to avoid more setbacks. We argue that Maranhão state must urgently establish a policy of Zero Deforestation, protect secondary forests and comply with the national forest restoration policy, thus ensuring long-term economic sustainability. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses the dynamics behind the establishment of scientific representations (e.g. reports, measurements, experiments) to the detriment of local representations (e.g. oral accounts, metaphors, symbols) in environmental policy-making in the Global South. To this end, the paper attempts to understand why local accounts of the Amazon in recent decades have gradually been replaced by satellite-based remote sensing (RS) technology in the region''s policy-making. RS technology is shown to provide representations that match policy-makers discourses as regards the importance of: visibility, since satellite images are believed to provide a transparent window from which the Amazon can be seen by policy-makers working from centres of power; comprehensiveness, since the data obtained through RS claims to represent the entire region; and determinacy, as forecasting and spatial correlation techniques establish deterministic links between particular factors (e.g. the presence of farmers, inflation) and environmental issues (e.g. increases in deforestation). From this examination, it is argued that rather than focusing on identifying the essential differences between local and scientific representation, more attention should be paid to how different kinds of representations are in harmony or conflict with historically rooted governance discourses. The article also indicates that in order to revalue local representations in environmental policy-making it is necessary to challenge particular discourses which are “taken-for-granted” in governance practices at the present time. [Copyright &y& Elsevier]

Abstract: This paper seeks to understand how the Brazilian Amazon, which many thought unsuitable for agricultural development, has yielded to a dynamic cattle economy in only a few decades. It does so by embedding the Thunian model of location rents within the regime of capital accumulation that has driven the Brazilian economy since the mid-20th century. The paper addresses policies that have created location rents in Amazônia, the effect of these rents on land managers, and the spatial implications of their behavior on forests. Thus, the paper connects macro-processes and structures to agents on the ground, in providing a political ecological explanation relevant to land change science. The policy discussion focuses on reductions in transportation costs, improvements in animal health, and monetary and trade reforms. To illustrate the impact of policy, the paper presents data on the geography of Amazonian herd expansion, on the growth of Amazonian exports, and on the profitability of the region’s cattle economy. It follows the empirical presentation with more abstract consideration of the spatial relations between cattle ranching and soy farming, and implications for deforestation. The paper concludes on a speculative note by considering the likelihood of forest transition in the region, given the transformation of Amazônia into a global resource frontier. [Copyright &y& Elsevier]

The relationship between human welfare and deforestation in the Brazilian Amazonia has traditionally been thought to follow a boom-and-bust pattern. According to this pattern, forest clearing triggers rapid increases in human welfare levels (“the boom”) due to short-term economic gains; these levels then drop to below national or regional averages (“the bust”) after the forest stocks have declined, thus causing the local populations to become deprived of ecosystem services. However, recent studies have questioned the validity of this boom-and-bust pattern. In this paper, we use panel data and simultaneous autoregressive models to evaluate the effects of deforestation, urbanization, public investments, agriculture, and state policies on temporal changes in human welfare that occurred across multiple municipalities in the Brazilian Amazonia from 2005 to 2012, a period during which governments implemented a set of strategies aimed at controlling deforestation across the region. We found that: (a) signals of a boom-and-bust pattern are weak at the regional level, and therefore this pattern cannot be generalized across the entire region; (b) human welfare is increasing more rapidly in low-development municipalities than in high-development cities, and all municipalities are converging on at least one regional average rather than on a national average; (c) urbanization does not lead to positive changes in human welfare, which indicates that the infrastructure available in regional urban centers is limited; (d) public investments are negatively associated with human welfare growth, thus signifying that if public investments are not used to leverage the potential of other sectors of the local economy, human welfare will not improve; (e) agriculture is negatively associated with positive changes in human welfare at the local level, possibly due to the dominance of cattle-ranching as the predominant economic activity of this sector; and (f) state-level policies matter, and future analyses of regional trends in the realm of development and conservation across this region should take such policies into account. Finally, we suggest that although human welfare and deforestation retain a weak statistical relationship, we cannot contend that they have been fully decoupled. Forest loss across the region is still pervasive, and institutions are too weak to sustain the transition from a frontier development model to a conservation-centered model. [ABSTRACT FROM AUTHOR]

The management and governance of shared stocks have long been identified as a challenge to achieve long-term sustainability in fisheries. This is the situation of fisheries in the Amazon basin, a region shared by nine countries. This paper provides an overview of the social-ecological outcomes and management implications of sharing fish stocks among countries with different public policies, taking the valuable Amazonian ornamental silver arawana ( Osteoglossum bicirrhosum ) trade as a case study. Specifically, it (i) presents and discusses the policies of Colombia, Peru and Brazil for the silver arawana fishery, and how these are conducive for the successful management of this shared transboundary fishery; and (ii) analyzes the market for the ornamental silver arawana and how it affects the ability to sustainably manage the fishery. The interplay between the multiple environmental, economic and social dimensions involved in the ornamental silver arawana fishery affects the sustainability of this species even in Brazil, where this fishing is forbidden but still illegally caught by Colombians and Peruvians. Among the factors that make fisheries policies inefficient in this region are: (i) incongruent policies between the countries and institutions with low organizational capacity to accomplish the established policies; (ii) environmental heterogeneity of Amazonian aquatic systems, which requires local and adaptive measures; and (iii) complex socio-economic relationships in the live-fish trade business. Legally binding efforts to reduce problems derived from shared fish stocks are an urgent need and should be addressed by the multilateral organizations created for the Amazonian sustainable development. [ABSTRACT FROM AUTHOR]

Suspended sediment yield is a very important environmental indicator within Amazonian fluvial systems, especially for rivers dominated by inorganic particles, referred to as white water rivers. For vast portions of Amazonian rivers, suspended sediment concentration (SSC) is measured infrequently or not at all. However, remote sensing techniques have been used to estimate water quality parameters worldwide, from which data for suspended matter is the most successfully retrieved. This paper presents empirical models for SSC retrieval in Amazonian white water rivers using reflectance data derived from Landsat 5/TM. The models use multiple regression for both the entire dataset (global model, N = 504) and for five segmented datasets (regional models) defined by general geological features of drainage basins. The models use VNIR bands, band ratios, and the SWIR band 5 as input. For the global model, the adjusted R 2 is 0.76, while the adjusted R 2 values for regional models vary from 0.77 to 0.89, all significant ( p -value < 0.0001). The regional models are subject to the leave-one-out cross validation technique, which presents robust results. The findings show that both the average error of estimation and the standard deviation increase as the SSC range increases. Regional models were more accurate when compared with the global model, suggesting changes in optical proprieties of water sampled at different sampling stations. Results confirm the potential for the estimation of SSC from Landsat/TM historical series data for the 1980s and 1990s, for which the in situ database is scarce. Such estimates supplement the SSC temporal series, providing a more comprehensive SSC temporal series which may show environmental dynamics yet unknown. [ABSTRACT FROM AUTHOR]

Abstract: This paper seeks to analyze local perspectives in Peruvian Amazon forest communities toward REDD and contrast those perspectives with current global and national REDD narratives. REDD is a global market-based approach to provide financial incentives for local actors to halt deforestation or to improve carbon stocks. To date, the REDD framework has not demonstrated that it is equipped to incorporate the diverse perspectives, potential interactions and uncertainties facing forest communities. We interviewed forest community members in the Amazonian state of Loreto, Peru, using “future scenarios” methods to elicit potential alternative narratives, both with and outside REDD. Indigenous voices reveal ambiguous attitudes toward REDD with regard to livelihoods, benefit distribution and the long-term impacts for communities and forests. They reveal considerable uncertainty about the future and lack of trust in governance regimes. Long-term community priorities were in generating work, providing educational opportunities for their children, and improving the quality of their forest. Conflict—within the community, with local loggers and with the recently established regional conservation area—was a prevalent theme. A REDD design that recognizes communities as active participants in global and national climate management and pays attention to local narratives will more likely generate the multiple benefits of healthy forests, strong communities and, ultimately, global climate change mitigation. [Copyright &y& Elsevier]

In this paper we analyze transformations within a land reform settlement in the Brazilian Amazon, with special land-use regulations targeting forest conservation. We conducted long-term action research in the Virola-Jatobá Sustainable Development Project (PDS), where peasant farmers who were the early settlers of the area, and more recent occupants allied to illegal loggers, land grabbers and speculators adopt antagonistic positions and challenge respective entitlements towards land and forest. In this research we highlight issues of power asymmetry and social injustice when assessing how social relations and environmental conditions in the study area are affected by land use and forest conservation policies since year 2000, when the scheme was established. The PDS situation approached a collapse in late 2017 when the integrity of its forests and the beliefs and practices of vulnerable local residents were damaged. This case study empirically demonstrates that Amazon forest frontier systems have a limited capacity to endure extreme perturbations in the social and ecological interconnected domains. We argue that when a threshold is reached in systems featuring heavily institutionalized social asymmetries that constrain the action of vulnerable resource users, few conditions remain to reorganize the constituent setup through adaptive changes in the same regime or state. Reaching this stage will likely result in drastic changes that will lock the system into a pathway that compromises human wellbeing and the provision of ecosystem services. The fundamental nature of a tenurial scheme that combines social justice and environmental conservation tends thus to be lost for good, to enter a new regime with fewer options and novelties in social-ecological advances, reflecting the overall setbacks currently experienced in Brazilian policy. • Failed delivery and enforcement of land and forest policy in Amazon forest frontier. • Land tenure modality in a liminal status between environmental and agrarian reform regulations. • Social support for conservation affected by political and economic factors mediated by governmental agencies. • A new regime takes place with lower complexity in both social and ecological terms. • Outcomes reflect overall setback in Brazil's current social and environmental policy. [ABSTRACT FROM AUTHOR]

Abstract: Analysing the factors that influence visitor satisfaction is critical for the appropriate management of tourism, particularly in nature tourism enterprises, which are expected to contribute to biodiversity conservation and the development of local people. In this paper, we investigate the effect of different socio-economic and ecological variables, as well as tourist-operation related factors, on the overall satisfaction of tourists visiting three Amazonian lodges in Peru. We found three typologies of tourists, differing by several socio-economic and cultural factors, and by their motivations. The quality of the lodge was the factor that had the largest influence on overall satisfaction. Only one type of tourists (“true ecotourists”) showed a positive relation between their overall satisfaction and ecological features such as the species observed or cultural features such as operation of the lodge by native communities using local guides. Implications for management are discussed in terms of the potential of nature tourism to contribute to sustainable development in the Peruvian Amazon. [Copyright &y& Elsevier]

Abstract: In Brazil, more than 14million people have benefited from the rural electrification program Luz Para Todos (LPT — Light for all), mainly through grid-extension. A new off-grid model is now required if remote areas in the Amazon region are to fully benefit from the program. In this paper, we explore the institutional and financial schemes that support LPT and their suitability for delivering off-grid solutions in the Amazon region. Our conclusions draw attention to the need for more local and site specific solutions, and new regulatory frameworks to allow the participation of new actors. We argue that the uniqueness of the Amazon region justifies renewable technologies focused on local needs and potential, adaptation of the LPT institutional framework and rethinking of funding channels. An off-grid approach will enhance the inclusion of remote areas in universal access goals while adjustments will help guarantee the sustainability of the electrification program. [Copyright &y& Elsevier]

Abstract: Considering the pressures on tropical forests from deforestation and the recent expansion of harvesting through forest concessions in the Brazilian Amazon, it is imperative that forest management systems are scrutinized to ensure sustainability. One of the basic problems in forest management is the correct identification of species within the forest stand. While this is a well known issue, little consideration is given to how to mitigate this problem or its affects on management practices and conservation. This paper examines the current practice of forest inventories in the Brazilian Amazon, as part of the mandatory system of reduced impact logging (RIL), using extensive forest inventory verification. The results show that the RIL management plan implemented in the project area was based on a highly inaccurate forest inventory. At least 132 species or 43.5% of all species identified after botanical checking did not appear in the forest inventory and the common practice of matching vernacular names to scientific ones proved to be severely deficient. In contrast, a high percentage of field identifications based on local people''s expertise were correct. We suggest changes to current practices, including the training and use of parataxonomists, the collection of samples for verification, and stricter government control over current practices, which will achieve greater accuracy in data collection and forest management planning. Ultimately, we argue that in the current climate of extensive deforestation and forest use, it is essential that all aspects of RIL systems are reevaluated in order to achieve economic and ecological sustainability. [Copyright &y& Elsevier]

Abstract: Estimates of greenhouse-gas emissions from deforestation are highly uncertain because of high variability in key parameters and because of the limited number of studies providing field measurements of these parameters. One such parameter is burning efficiency, which determines how much of the original forest''s aboveground carbon stock will be released in the burn, as well as how much will later be released by decay and how much will remain as charcoal. In this paper we examined the fate of biomass from a semideciduous tropical forest in the “arc of deforestation,” where clearing activity is concentrated along the southern edge of the Amazon forest. We estimated carbon content, charcoal formation and burning efficiency by direct measurements (cutting and weighing) and by line-intersect sampling (LIS) done along the axis of each plot before and after burning of felled vegetation. The total aboveground dry biomass found here (219.3Mgha−1) is lower than the values found in studies that have been done in other parts of the Amazon region. Values for burning efficiency (65%) and charcoal formation (6.0%, or 5.98MgCha−1) were much higher than those found in past studies in tropical areas. The percentage of trunk biomass lost in burning (49%) was substantially higher than has been found in previous studies. This difference may be explained by the concentration of more stems in the smaller diameter classes and the low humidity of the fuel (the dry season was unusually long in 2007, the year of the burn). This study provides the first measurements of forest burning parameters for a group of forest types that is now undergoing rapid deforestation. The burning parameters estimated here indicate substantially higher burning efficiency than has been found in other Amazonian forest types. Quantification of burning efficiency is critical to estimates of trace-gas emissions from deforestation. [Copyright &y& Elsevier]

Abstract: The ecological consequences of climate change for large tropical forests such as the Amazon are likely to be profound. Amazonian forests strongly influence regional and global climates and therefore any changes in forest structure, such as deforestation or die-back, may create positive feedback on externally forced climate change. Monitoring, modelling and managing the impacts of anthropogenic climate change on forest dynamics is therefore an important objective of forest researchers, and one that requires long-term data on changes at the level of community, populations and phenotypes. In this paper we provide the most comprehensive study yet on the seasonal dynamics of various leaf traits: leaf area index (LAI), leaf mortality (LM), leaf biomass (LB), leaf growth rate (LG), and leaf residence time (TR) from 50 experimental plots in a forest site at Belterra, Pará State, Brazil. From this study we estimate annual mean leaf area index (LAI) to be 5.07m2 m−2 and annual mean leaf dry biomass to be 0.621kgm−2. The typical leaf grew at 0.049kgm−2 month−1 and remained on the tree for 12.7 months. We compare these results to other similar studies and critically discuss the factors driving leaf demographics in Amazonia. [Copyright &y& Elsevier]

Abstract: This paper examines the extensive regions of Proterozoic accretionary belts that either formed most of the Amazonian Craton, or are marginal to its southeastern border. Their overall geodynamic significance is considered taking into account the paleogeographic reconstruction of Columbia, Rodinia and Gondwana. Amazonia would be part of Columbia together with Laurentia, North China and Baltica, forming a continuous, continental landmass linked by the Paleo- to Mesoproterozoic mobile belts that constitute large portions of it. The Rodinia supercontinent was formed in the Mesoproterozoic by the agglutination of the existing cratonic fragments, such as Laurentia and Amazonia, during contemporary continental collisions worldwide. The available paleomagnetic data suggest that Laurentia and Amazonia remained attached until at least 600 Ma. Since all other cratonic units surrounding Laurentia have already rifted away by that time, the separation between Amazonia and Laurentia marks the final break-up of Rodinia with the opening of the lapetus ocean. [Copyright &y& Elsevier]

Abstract: Tropical forests are characterized by diverse assemblages of plant and animal species compared to temperate forests. Corollary to this general rule is that most tree species, whether valued for timber or not, occur at low densities (<1adulttreeha−1) or may be locally rare. In the Brazilian Amazon, many of the most highly valued timber species occur at extremely low densities yet are intensively harvested with little regard for impacts on population structures and dynamics. These include big-leaf mahogany (Swietenia macrophylla), ipê (Tabebuia serratifolia and Tabebuia impetiginosa), jatobá (Hymenaea courbaril), and freijó cinza (Cordia goeldiana). Brazilian forest regulations prohibit harvests of species that meet the legal definition of rare – fewer than three trees per 100ha – but treat all species populations exceeding this density threshold equally. In this paper we simulate logging impacts on a group of timber species occurring at low densities that are widely distributed across eastern and southern Amazonia, based on field data collected at four research sites since 1997, asking: under current Brazilian forest legislation, what are the prospects for second harvests on 30-year cutting cycles given observed population structures, growth, and mortality rates? Ecologically ‘rare’ species constitute majorities in commercial species assemblages in all but one of the seven large-scale inventories we analyzed from sites spanning the Amazon (range 49–100% of total commercial species). Although densities of only six of 37 study species populations met the Brazilian legal definition of a rare species, timber stocks of five of the six timber species declined substantially at all sites between first and second harvests in simulations based on legally allowable harvest intensities. Reducing species-level harvest intensity by increasing minimum felling diameters or increasing seed tree retention levels improved prospects for second harvests of those populations with a relatively high proportion of submerchantable stems, but did not dramatically improve projections for populations with relatively flat diameter distributions. We argue that restrictions on logging very low-density timber tree populations, such as the current Brazilian standard, provide inadequate minimum protection for vulnerable species. Population declines, even if reduced-impact logging (RIL) is eventually adopted uniformly, can be anticipated for a large pool of high-value timber species unless harvest intensities are adapted to timber species population ecology, and silvicultural treatments are adopted to remedy poor natural stocking in logged stands. [Copyright &y& Elsevier]

Abstract: Wood density is an important variable in estimates of biomass and carbon flux in tropical regions. However, the Amazon region lacks large-scale wood-density datasets that employ a sampling methodology adequate for use in estimates of biomass and carbon emissions. Normalization of the available datasets is needed to avoid bias in estimates that combine previous studies of wood density that used wood sampling at diverse positions in the bole or with various methods of density determination. This paper examines the question of whether regressions for radial variation and for variation in wood density along the bole, both developed in dense forest in central Amazonia (CA), are suitable for the open forests in southern Amazonia (SA) that are currently the target of most of Amazonia''s deforestation activity. The wood density of the heartwood and density of full disks or slices (bark, sapwood and heartwood) in each tree were measured to assess the radial variation. For variation along the length of the bole, wood densities at breast height and at the top of the bole were used. Moisture content of the bole was measured in SA and compared with values reported by studies from CA in similar dense forest. Comparing regressions that predict full-disk density from heartwood density, the pattern of radial variation differs slightly and significantly between the two forest types (ANCOVA p =0.006); the slopes have similar values but the intercepts differ. Variation along the bole in the two forest types does not differ significantly (p =0.144), so the CA model for predicting mean bole density from the density of a slice at breast height gives an unbiased estimate of the mean bole density when applied to SA trees. In SA the mean moisture content of the bole was 0.416 (±0.068 S.D.; n =223 trees). Moisture content of the bole had a strong inverse relationship with basic wood density (r =−0.77), which explains the lower moisture content in the trees in CA relative to SA. A much weaker inverse relationship was found between moisture content and green wood density (r =−0.292). The relationship between wood basic density and green (‘fresh’) density presented in this study provides an alternative means of obtaining basic wood density directly in the field when oven drying of samples is not possible. [Copyright &y& Elsevier]