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• The project 'Tropical Biomass & Carbon' and its main product TB&C App is introduced. • TB&C App is an user-friendly tool that estimates C stored in forests of Brazil. • Model performance analysis proved reliability >95% of the TB&C App's models. • Carbon in Amazonian forests can be accurately and precisely estimated. • A dataset containing 64,000 plots with forest variables is delivered as supplement. This article introduces the Tropical Biomass & Carbon Application – the 'TB&C App', a web application available on the permanent link www.tropicalbiomass.com. The TB&C App requires as input attributes 'the smallest and largest diameters', 'number of trees ha−1', basal area ha−1, and 'parameters of the diameter (beta) distribution' describing stand structure. The App delivers outputs at two levels: (1) Stand level, including mean aboveground biomass (AGB) and carbon (AGC), in Mg ha−1, along with confidence intervals (CIs) as measures of uncertainty, and; (2) Tree level estimates, with AGB and diameter for every simulated tree. Phase 1 of the project TB&C comprises four Brazilian forest (and non-forest) formations: Campinarana, Floresta estacional, Floresta ombrofila , and Savana. This article aims to (i) describe the algorithm written for the TB&C App, and (ii) present results of Phase 1. This first phase counts on a standardized database of 1,428 trees with field-measured dry AGB, from plots across the different formations, which is the largest tree-biomass database compiled so far in Brazil. Model uncertainties were incorporated into the modeling process, allowing computation of CIs through an uncertainty approach. The total variance of residuals of AGB was also modeled, aiming at predicting CIs as a function of the quantity of AGB. An analysis of reliability of the equations implemented in the TB&C App indicates that more than 95% (n = 64,000) of the true AGB's fit into the CI outputted by the TB&C App. A comparison with other approaches in the literature shows significant agreement with previous estimates and more conservative estimates where previously-published estimates disagreed with the TB&C App. We cite as advantages of the TB&C App; (i) reliability of the outputs, (ii) a user-friendly layout, (iii) AGB and AGC estimates provided along with robust CIs, and (iv) estimates at the stand and tree levels with consistent totals. A biomass dataset containing information on 64,000 plots is also delivered as supplement of this paper. [ABSTRACT FROM AUTHOR]

Kaolin is a clay mineral with several applications, especially as filler in the paper industry. Brazil has the largest kaolin processing plant in the world located in the Amazon region. Kaolin mining activities generate high volumes of waste, resulting in additional costs and environmental impacts, and therefore, new approaches for their reduction are necessary. This work elucidates, for the first time, the technological valorization of abundant Amazon Brazilian kaolin mining waste to synthesize pure-phase zeolitic material with the antibacterial application. For the synthesis optimization, it was evaluated the influence of the type of kaolin (natural or thermally treated at 600 °C), the crystallization period (4, 6 and 24 h), the suppression of aluminum source (sodium aluminate) and the zinc ion-exchanging procedure. The materials were characterized by various techniques including powder X-ray diffraction (XRD), aluminum nuclear magnetic resonance with magic-angle spinning (27Al MAS NMR) and X-ray photoelectron spectroscopy (XPS), N 2 adsorption/desorption isotherms, chemical analysis, thermogravimetric analysis (TGA), infrared spectroscopy (IR) and scanning electron microscopy (SEM). The results reveal that it is possible to direct the synthesis to the different zeolite structure with simple thermal treatment of the raw material, obtaining crystalline Linde Type A (LTA) or sodalite (SOD) zeolites using thermally treated or natural kaolin, respectively. Under the optimized synthesis conditions, the LTA zeolite was obtained after rapid crystallization in 6 h and without commercial aluminum supplementation. The Zn-exchanged LTA zeolites containing 4 and 7 wt% of Zn were applied as antibacterial materials. They presented growth inhibition zones between 7 and 8 mm for Gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella enterica) while pure kaolin and LTA zeolite without Zn did not show antibacterial activity. These results offer new opportunities on the way that kaolin-mining industries manage their wastes. [Display omitted] • Pure kaolin led to obtaining pure-phase SOD-type zeolite. • Thermally treated kaolin led to obtaining pure-phase LTA-type zeolite. • The zinc-LTA exhibited activity against gram-positive bacteria (L monocytogenes and S. aureus). • The zinc-LTA exhibited activity against gram-negative bacteria (E.coli and S. choleraesuis). • The zinc-LTA exhibited growth inhibition zones between 7 and 8 mm for all studied bacteria. Abstract: [ABSTRACT FROM AUTHOR]

• Air pollution in the Brazilian Amazon leads to increases in hospitalization rates. • Adverse effects are concentrated in respiratory conditions. • Effects are higher among children and the elderly. • Effects increase non-linearly with air pollution levels. • There are negative externalities related to deforestation in the Brazilian Amazon. In this paper we assess the effects of fire-related air pollution on population health in the Brazilian Amazon. Our empirical strategy is based on a municipality-by-month fixed effects model, coupled with an instrumental variables approach that explores wind direction and air pollution in surrounding areas in order to exogenously shift exposure to air pollution at the locality. We find that exposure to air pollution, measured by PM2.5 concentration levels, is robustly associated with an increase in hospital admissions for respiratory conditions. The effects are higher among children and the elderly, and increase non-linearly with pollution levels. Our benchmark estimates indicate that an increase of one standard deviation in PM2.5 is related to an increase of 1.5% of the monthly hospitalization rate for respiratory conditions. The latter estimate reaches 14% if monthly average PM2.5 crosses thresholds as high as 75 μ g/m3. We do not observe significant effects on hospitalization rates related to other health conditions nor on mortality rates. [ABSTRACT FROM AUTHOR]

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]