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This study aimed to investigate the impact of as-received biomass fly ashes (BFA) and green liquor dregs obtained from a pulp and paper plant in Brazil as substitutes for metakaolin in geopolymeric formulations. The properties of this type of waste material vary widely between different industrial plants. This study refrains from subjecting the waste materials to any form of pretreatment, taking into account their organic matter and particle size heterogeneity, requiring extensive characterization to evaluate their influence on the compressive strength, apparent open porosity, and water absorption of the geopolymeric samples. The objective was to assess their potential for upcycling purposes as an alternative to energy-intensive materials, such as ordinary Portland cement (OPC) and advanced ceramics. This potential arises from the ability of alkali-activated materials (AAM) to undergo curing at ambient temperatures, coupled with the possibility of compositions primarily derived from waste materials. To improve the sustainability of the products, the amorphous content of the raw material, which is more reactive than crystalline phases, was quantified and used as the base for mixture ratios. This approach aimed to reduce the requirement for alkaline activators, which have significant environmental impacts, while also increasing the waste content in the formulation. The incorporation of waste materials into the geopolymer matrix generally led to a reduction in the compressive strength compared to the benchmark metakaolin sample (19.4 MPa) but did not present a trend. The dregs led to values of 4.1 MPa at 25 wt% and 7.1 MPa at 50 wt%, a behavior that is somewhat counterintuitive, and BFA at 10 wt% presented 5.7 MPa. Nevertheless, the apparent open porosity remained at high levels for all the samples, close to 50%, and the compressive strength of most of them was over the values obtained for the metakaolin-only samples with mixture ratios calculated from the total composition instead of the amorphous composition. The decrease in strength and the increase in porosity were attributed to the specific characteristics of the waste materials, such as their high crystallinity, presence of organic matter, heterogeneous particle composition, and size. Overall, this study provides insight into the variations in geopolymerization based on the bulk and amorphous content of the aluminosilicate sources and how the characteristics of the waste materials influence the geopolymer matrix. It also highlights how calculating mixture ratios based on the amorphous composition improves the possibility of waste valorization through alkali activation. Additionally, it suggests that BFA and dregs might be effectively utilized in applications other than OPC substitution, such as adsorption, filtration, and catalysis. [ABSTRACT FROM AUTHOR]

Transitioning from gasoline and petroleum‐based products to biofuels and green chemicals is a paradigm shift that will lead to the development of the bioeconomy. In this sense, the role of biorefineries in countries like Brazil is very important as the country generates a huge amount of second generation (2G) biomass every year and also has an attractive consumable market. However, technological innovations are still required to unleash the fullest potential of biomass conversion to biofuels and biochemicals, although successful examples are already a reality. For example, Amyris Inc. has developed renewable products for cosmetics (squalene), healthcare (artemisinin), and flavors / fragrances, and Suzano Papel e Celulose has developed sustainable technologies for the production of pulp and paper, and lignin‐derived adhesives (Ecolig). First‐generation ethanol in Brazil is an established source of transportation fuel but 2G ethanol production with low production costs is still a challenge at commercial scale, and companies like Raízen and GranBio continue making efforts to improve the economic feasibility of the adopted processes. In this context, the RenovaBio Policy launched by the Federal Brazilian Government in December 2017 aims to boost the production and utilization of biofuels and green chemicals in the country. Considering the matters mentioned above, this paper discusses the Brazilian biorefinery developments, technological advances, and current industrial scenario for the production of biofuels and chemicals. © 2021 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Biomass is an important indicator of the ability of tropical forests to deliver ecosystem services, but little attention has been given to belowground biomass and its drivers in human-modified landscapes. Here, we investigated the belowground biomass and nutrient concentration/stocks (C, P, and N) across regenerating forest stands with varying ages (10-76 years old) and old-growth forests in the Caatinga dry forest (northeastern Brazil) in the context of slash-and-burn agriculture. Belowground biomass ranged from 1.89 ± 0.33 Mg ha -1 to 17.53 ± 2.28 Mg ha -1 (mean ± SE) across regenerating forest stands and averaged 8.33 ± 1.59 Mg ha -1 , with no differences compared to old-growth stands. However, regenerating stands exhibited a higher root/shoot ratio with biomass concentrated in the superficial soil layer and in large-sized roots, regardless of the successional stage. Root nutrient concentration and stocks were highly variable across forest stands with fine roots supporting a higher concentration of N and P, while regenerating stands supported lower nutrient stocks as compared to old-growth forests. Finally, precipitation and chronic disturbance emerged as the most important drivers of belowground biomass and nutrient concentrations/stocks, while aboveground biomass played a negligible role. Our results indicate that, in human-modified landscapes of tropical dry forests, belowground biomass and nutrients play important roles in ecosystem functions in regenerated forests after slash-and-burn agriculture. Forest resilience and provision of ecosystem services (e.g., nutrient cycling) appear to be very sensitive to increased aridity and exploitation of forest resources., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Crop canopy optical reflectance and ultrasonic sensors provide a means of estimating the spatial variability of biomass and nitrogen uptake by sugarcane during the in-season period. The objective of this paper is to assess the crop canopy reflectance and ultrasonic crop height for predicting sugarcane biomass and N-uptake until the later fertilization stages. An ultrasonic sensor was deployed to measure canopy height, which were combined with optical reflectance sensor to characterize the spatial variability of the crop growth in four commercial fields in southeast Brazil during three different growing stages for dry and wet seasons. Ten sampling location points in each field were defined to determine plant biomass and N-uptake through traditional measurements. The points in each field were used to relate the actual biomass and N-uptake with the sensor data and compare them using the coefficient of determination and standard errors; this defined the best approach in each situation according to the multivariable statistics. It was found that both sensor systems enable to correlate its data with sugarcane biomass and N-uptake. Canopy reflectance sensor produced a better assessment of crop growth at the earlier growth stage whereas the ultrasonic sensor resulted in more accurate predictions at the later growing stages. It was proven that canopy height is season dependent whereas the reflectance data is growth stage dependent. The integration of both sensing systems improved the predictions of sugarcane biomass and N-uptake. It could be an alternative to guide local interventions by sugarcane industry during the growing season. [ABSTRACT FROM AUTHOR]

The Amazon Forest, the largest contiguous tropical forest in the world, stores a significant fraction of the carbon on land. Changes in climate and land use affect total carbon stocks, making it critical to continuously update and revise the best estimates for the region, particularly considering changes in forest dynamics. Forest inventory data cover only a tiny fraction of the Amazon region, and the coverage is not sufficient to ensure reliable data interpolation and validation. This paper presents a new forest above-ground biomass map for the Brazilian Amazon and the associated uncertainty both with a resolution of 250 meters and baseline for the satellite dataset the year of 2016 (i.e., the year of the satellite observation). A significant increase in data availability from forest inventories and remote sensing has enabled progress towards high-resolution biomass estimates. This work uses the largest airborne LiDAR database ever collected in the Amazon, mapping 360,000 km 2 through transects distributed in all vegetation categories in the region. The map uses airborne laser scanning (ALS) data calibrated by field forest inventories that are extrapolated to the region using a machine learning approach with inputs from Synthetic Aperture Radar (PALSAR), vegetation indices obtained from the Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite, and precipitation information from the Tropical Rainfall Measuring Mission (TRMM). A total of 174 field inventories geolocated using a Differential Global Positioning System (DGPS) were used to validate the biomass estimations. The experimental design allowed for a comprehensive representation of several vegetation types, producing an above-ground biomass map varying from a maximum value of 518 Mg ha -1 , a mean of 174 Mg ha -1 , and a standard deviation of 102 Mg ha -1 . This unique dataset enabled a better representation of the regional distribution of the forest biomass and structure, providing further studies and critical information for decision-making concerning forest conservation, planning, carbon emissions estimate, and mechanisms for supporting carbon emissions reductions., (© 2023. Springer Nature Limited.)

Paper aims: The research aims to identify the main barriers to scaling up the energy production expansion systems from biogas and biomass in Brazil. Originality: This article aggregates information and different perceptions from a systemic view for bioelectricity production from biomass. It brings to the fore the discussion of bioenergy production from other types of biomass, which encompass a wide range of actors in the production chain. Research method: We adopted a qualitative approach by applying semi-structured interviews with 19 experts from 15 institutions considering various biomass and biogas power generation segments. Main findings: This paper identifies five barrier categories that restrain or affect the country's broad electricity production from biomass and biogas: circumstantial, cultural, technical, and include other uses of biogas and biomethane. The financial and cultural barriers are the most mentioned by the experts. Financial difficulties of the plants, sector conservatism, issues in the electricity sector, and lack of knowledge limit the potential and interest in developing new projects. Implications for theory and practice: The results contribute to the development of sectoral public policies as it brings up non-explicit information and reveals broad perspectives aimed at integrating the themes of biogas and biomass. Also, the research adds to the debate on the analysis boundaries of this theme and can support future empirical studies in developing countries that seek to expand renewable sources to power generation from biomass. [ABSTRACT FROM AUTHOR]

Copyright of Revista em Agronegócio e Meio Ambiente is the property of Revista em Agronegocio e Meio Ambiente and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Major progress in the bioprocessing of lignocellulose to fuels and value‐added chemicals has created the possibility of a low carbon‐footprint economy. However, the current complexity and associated costs of lignocellulose conversion result in a higher price for ethanol than for fossil fuels. The cost of cellulosic ethanol production will be lowered by further progress in development of biorefinery technology that produces both ethanol and high‐value chemicals with bio‐based products that are beginning to penetrate consumer markets in the USA, Brazil, and worldwide. The cost‐effectiveness of low carbon‐footprint bioproducts will benefit from advances in supplying large amounts of biomass solids to the biorefinery. We describe here outcomes from a successful long‐term international cooperation between the Laboratory of Renewable Resources Engineering (LORRE) at Purdue University in the United States and Brazil's Agricultural Research Corporation (EMBRAPA) and Federal University of São Carlos (UFSCar), which has contributed practical pathways to enhance the biorefinery concept. This paper gives an overview of developments that address fundamental knowledge of lignocellulosic biomass pretreatment hydrolysis under optimized operational conditions and bioreactor configurations, and the science and engineering that contributes to the effective production of fuel and ethanol and value‐added products from biomass. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Cogeneration systems have gained prominence in recent years driven by the simultaneous systematic production of heat and electricity, which are involved in industrial and commercial processes. Sugar and alcohol industry has become a reference in the use of cogeneration through the burning of sugarcane bagasse, with an important role in the future policies for generation expansion in Brazil. However, in the economic evaluation of this type of project, some previously ignored variables had a gain of relevance, such as the possibility of selling surplus energy produced by the plant. This paper presents a multiobjective stochastic optimization model using stochastic dynamic dual programming techniques, which seeks to maximize net revenue of a cogeneration project, indicating also the installed power adequate to the fuel availability and the needs of the plant, considering different energy scenarios in the spot market. The results indicate the best configuration for a cogeneration plant, considering the possibility of energy revenue, allowing an easy cost comparison of different alternatives for decision making from the investor's point of view. [ABSTRACT FROM AUTHOR]

Several economies around the world are using second-generation (2G) ethanol produced from agricultural residues, like sugarcane straw and bagasse, as a sustainable solution to replace petroleum products. Since first-generation (1G) ethanol uses the sugars of sugarcane, an integrated 1G⁻2G production would enable the production of more ethanol from the same amount of sugarcane without leading to increased use of arable land. The ethanol production process is complex, involving different high-energy consumption operations such as evaporation and distillation. The economic competitiveness of this process depends heavily on the amount of thermal and electrical energy produced using sugarcane straw and bagasse as input. Thus, the objective of this study was to use the mean-variance methodology to determine the optimal allocation of residual sugarcane biomass between 2G ethanol and bioelectricity productions, with simultaneous objectives of maximizing the return and minimizing the risk for investors of this sector. In this paper, four scenarios are analyzed. The first one is the base scenario that represents the current state of production costs and investments. scenarios 2, 3, and 4 considered four cuts of 10%, 20%, and 40% in the production cost of ethanol 2G, respectively. The results show the optimum biomass allocations and the growth rates of returns as a function of risk growth. It can be concluded that from scenario 4, the production of 2G ethanol becomes financially advantageous for the investor, presenting greater returns with smaller risks.

Considering the potential use of lignocellulosic biomass residues in microbial cultures to produce cellulases, the objective of this research was to investigate trends and discussions regarding scientific research conducted in this field through a bibliometric and scientometric analysis. Using the Elsevier Scopus database and VOSviewer software, scientific papers published between 2007 and 2018 were investigated. The results showed that the production of cellulases is related to obtaining xylanases and glucose. Obtaining of bioethanol and determining cellulolytic and xylanase activities were the relevant indicators for the use of these enzymes. China, India and Brazil are countries with a high number of publications in this field, most likely due to investments made between 2015 and 2017. This analysis showed that research on the use of lignocellulosic residues is focused on obtaining biofuels through enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]

• A generic optimization model for biorefineries design overarching the entire supply chain, from biomass to market, that allows the modeling of complex biomass systems, such as forests. • A robust formulation that handles uncertainties on both biomass productivity and product selling prices. • An uncertainty model that allows the control of the degree of conservatism regarding negative uncertainties materialization. • A case study for a eucalyptus biorefinery implementation in Brazil producing paper-grade pulp, electricity, and lignin illustrating the capabilities of the proposed model. The dependence of biomass growth on uncontrolled environmental factors and the lack of confidence in product selling price estimation imposes challenges for the efficient design of biorefineries, especially for forest systems, which present complex and long-termed growth behavior. The present work proposes the expansion of an optimization framework for forest biorefineries design to handle uncertainties on both biomass productivity and product selling prices. A robust formulation is proposed under a box and polyhedral uncertainty set formulation allowing its conservatism degree to be controlled. A case study of a eucalyptus biorefinery in Brazil illustrates the model's capabilities. The canonical worst-case approach to uncertainties on selling prices leads to a null optimal Net Present Value (NPV) and, on biomass growth, leads to a design that uses a 70% excess of lands. Scenarios of a controlled degree of conservatism lead to designs closer to the uncertainty-free optimal NPV of 136 bi BRL. [ABSTRACT FROM AUTHOR]

Seaweed is a fast-growing biomass source that is currently studied as feedstock for sustainable industrial production in a wide variety of markets. Being composed mostly of polysaccharides, macroalgae can be integrated in biorefineries for obtaining bioproducts via fermentation. Kappaphycus alvarezii has been introduced experimentally to Brazil's south coastline in 1995 and is now cultivated on a large scale to keep up with the high carrageenan demand in various industrial sectors. In this review article, an introduction is given on renewable biomass and environmental issues, focusing especially on third-generation biomass and its promising features and use advantages. Later on, the processing of K. alvarezii for the use of its saccharide portion for fermentative processes is approached. The current state of research conducted alongside challenges and hurdles in K. alvarezii hydrolysate fermentation processes provides insight into future studies needed to make new fermentation processes viable. Next, some fermentation products are discussed, and the metabolism of galactose in microorganisms is also presented to bring to light other possible fermentation products that are not yet, but can be, obtained from K. alvarezii. Finally, a simple and comprehensive scheme for K. alvarezii fermentation biorefinery is presented to demonstrate a generic example for a possible configuration for obtaining valuable bio-products. In the literature, production of ethanol and lactic acid were already reported from K. alvarezii. This review aims to help envision new industrial processes that can be developed for this most valuable macroalga. [ABSTRACT FROM AUTHOR]

Selecting adapted hybrids with greater efficiency in the use and return of nutrients is essential to ensure the success of forestry activities. Although topics on the nutritional sustainability of eucalypt biomass harvesting have frequently been discussed, few studies have focused on short rotation eucalypt clonal plantations (aimed at energy production), especially in conditions of nutrient scarcity and water limitations in Brazil. Therefore, our objective was to evaluate the nutritional efficiency and sustainability (for nitrogen (N), phosphorus (P) and potassium (K)) of six eucalypt clones in short rotation cultivation in the north-east of Brazil, considering different harvesting scenarios and using the Eucalyptus urophylla species as a reference, which is traditionally planted in the study region. Direct quantification of the biomass of 21 trees of each clone was carried out at 5 years of age. The clones did not affect the accumulation of total biomass (on average, 199.9 Mg ha−1). The 1296 and 1355 clones provided lower biomass export and greater nutritional efficiency, favouring an increase in the potential number of rotations (PNR) for P and a reduction in the N removal rate (RR). However, the VM58 clone showed higher biomass export and lower PNR. Thus, clones 1296 and 1355 are more favourable, while clone VM58 is less favourable to nutritional sustainability under the studied conditions. Nitrogen and K may cause productivity limitations in future rotations in whole-tree harvesting systems. Adopting more conservationist harvesting systems with removing only the stemwood or stemwood with bark can optimise the potential of clones, minimise the need to add fertilisers and ensure maintenance of the site's productivity. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the wood chemical and energetic characteristics of Eucalyptus spp. clones planted in three sites in the Midwest of Brazil. Thus, five clones from Eucalyptus spp. were planted in different sites aiming to determine the qualitative characteristics of the wood resulting from the variation in the tree growth environment and the genetic material. The same clones were planted in the three sites to determine the genotype × environment interaction. The trees were then sampled at 5 years after planting for their physical–chemical and energetic characterization. The results showed that the wood characteristics vary in different proportions according to the clone, just as the growth environment of the trees alters the behavior of the clones for the same characteristics. The edaphic variables affected the wood characteristics, inferring that the water content in the soil has more effect on the wood properties than the water content in the air, mainly on wood basic density. The results of this study indicate that using the appropriate genotype related to the environment conditions determines the wood characteristics, since the wood properties are strongly influenced by the edaphoclimatic variables. [ABSTRACT FROM AUTHOR]

The present paper presents the first population data for the Southern Hemisphere of the rare seagrass Halophila baillonis. The population studied is located in a calm, reef-protected area at depths ≤ 5 m, covering 12,000 m2 (400 m long by 30 m wide, oriented parallel to the coastline). The population generally demonstrated low shoot density and biomass during the rainy season, with significant differences between seasons, being found only for aboveground biomass. Despite the identification of this new population, the species continues to be considered rare along the Brazilian coast.

Brazil is the world's leading charcoal producer, mainly used as an energy source and reducing agent for iron ore in the pig iron and steel industry. Despite its vast production, much of the Brazilian charcoal production remains low-tech and inefficient, with limited utilization of by-products. To address potential environmental impacts, promote a circular economy, and reduce energy waste in the charcoal production chain, this study presents the benefits of using wood carbonization by-products through a Life Cycle Assessment (LCA). The analysis was performed by comparing four scenarios: i) Current wood carbonization; ii) Wood carbonization with combustion of non-condensable gases; iii) Wood carbonization with energy recovering of non-condensable gases for electricity generation; and iv) Assessing the utilization of insoluble tar and biomass waste for generating additional electricity, and the use of Pyroligneous Extract (PE) in eucalyptus cultivation. The results demonstrate that by-product utilization prevents energy waste, with an estimated potential to generate 0.19–0.26 MWh per ton of charcoal in Scenarios 3 and 4. Furthermore, 3.3 t of CO2 eq./t of charcoal are sequestered from the atmosphere, and Scenarios 2, 3, and 4 can increase this amount by 5.06%, 6.7%, and 0.48%, respectively. This paper introduces an innovative assessment of PE utilization during eucalyptus cultivation, resulting in a 6.16% reduction in greenhouse gas emission and a 46.98% decrease in abiotic resource consumption, attributed to PE's potential to partially reduce pesticide consumption. [Display omitted] • Photochemical Oxidation is the main impact category due to CO emissions in carbonization kilns. • Potential to generate 0.19–0.26 MWh of electricity per ton of charcoal through by-products utilization. • Forest residues and insoluble tar increase electricity generation potential by 36%. • Charcoal by-products offset GHG emissions from 14 to 203 kg/ton of charcoal. • Pyroligneous Extract use leads to 6% lower GHG emissions and 47% decrease in abiotic resource consumption. [ABSTRACT FROM AUTHOR]

Pteridium is a cosmopolitan genus that acts as an invasive species in many parts of the world. Most research on this genus has occurred in Europe, and there is a lack of data on it from South America, in spite of causing considerable conservation problems. We compared the biomass allocation of P. esculentum subsp. arachnoideum in two ecosystems in Brazil - Atlantic forest and Brazilian savanna. We measured the biomass of fronds, rhizomes and above-ground litter. We also compared the density, length and biomass of fronds from this Brazilian study with similar data of P. esculentum subsp. arachnoideum derived from Venezuela and P. aquilinum from Europe. P. esculentum subsp. arachnoideum showed a wide response range. We found a negative relationship between frond and necromass, indicating a negative feedback effect, while a positive relationship was observed between frond and rhizome biomass. The continental comparison of relationships showed that Pteridium responds in a different way in both Brazil and Europe, and that in Brazil fronds tend to be longer and heavier, presumably as a result of the continuous growing season in South America while is shortened in Europe by frost. The paper shows the ability of Pteridium to adapt to different ecosystems.

The powdered biomass of paddle cactus (Tacinga palmadora), a rustic plant of great occurrence in the driest regions of Brazil, was evaluated as a low-cost adsorbent to treat textile effluents containing crystal violet (CV) dye. The powdered paddle cactus (PPC) was mainly composed by lignin and holocellulose, as well as, a variety of functional groups. Best results for CV adsorption were found using an adsorbent dosage of 0.5 g L−1 at solution pH equivalent to 10.0. Fast adsorption kinetics was verified, being the equilibrium reached within 100 min, and the curves were well modeled by the pseudo-first-order model. The isotherms were well-represented by the Langmuir model. The maximum adsorption capacity was 228.74 mg g−1 at 328 K. The estimated thermodynamics parameters were ΔG0T = 328K of –9.08 kJ mol−1, ΔH0 of 12.44 kJ mol−1, and ΔS0 of 0.065 kJ mol−1 K−1. In addition, PPC was able to treat a simulated textile effluent containing organic and inorganic compounds, reaching 93% of color removal efficiency. These findings show that powdered paddle cactus can be applied as potential low-cost adsorbent to treat textile effluents containing CV. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería y Universidad is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an historical approach on the development of the existing biomass carbonization technologies in industrial operation in Brazil, the biggest charcoal producing country in the world. The gravimetric yield of charcoal from wood does not usually surpass 25%; the time of each operation cycle is more than seven days; and less than 50% of the energy contained in the feedstock is transformed into charcoal – the rest is discharged into the environment. The electricity generation associated with charcoal production is nowadays inexistent in Brazil. This paper presents the development of an industrial technology of semi-continuous pyrolysis process, characterized by using metallic kilns with forced exhaust system: the Rima Container Kiln (RCK). The results of the test runs are related to 5 m 3 and 40 m 3 kilns, with a thermal power of 200 kW (pilot scale: 5 m 3 ) and 3000 kW (industrial scale: 40 m 3 ). The low heating value of the pyrolysis gases is 670 and 1470 kJ/m³, respectively. The main results are: a 3 h carbonization time; an average productivity per kiln of 1 ton of charcoal per hour; and a gravimetric yield of 35%. In this paper, four scenarios for the conversion of exhaust gases and tar into electricity were evaluated: the Conventional Rankine Cycle (CRC) and the Organic Rankine Cycle (ORC), each one with and without forest residues utilization. It is shown that the best economic indicators correspond to the scenario where ORC technology is used. The electricity generation cost is around U$30/MWhe for ORC and US$40/MWhe for CRC. [ABSTRACT FROM AUTHOR]

Background: The use of biomass for cooking and heating is considered an important factor associated with respiratory diseases. However, few studies evaluate the amount of particulate matter less than 2.5 μm in diameter (PM2.5), symptoms and lung function in the same population., Objectives: To evaluate the respiratory effects of biomass combustion and compare the results with those of individuals from the same community in Brazil using liquefied petroleum gas (Gas)., Methods: 1402 individuals in 260 residences were divided into three groups according to exposure (Gas, Indoor-Biomass, Outside-Biomass). Respiratory symptoms were assessed using questionnaires. Reflectance of paper filters was used to assess particulate matter exposure. In 48 residences the amount of PM2.5 was also quantified. Pulmonary function tests were performed in 120 individuals., Results: Reflectance index correlated directly with PM2.5 (r=0.92) and was used to estimate exposure (ePM2.5). There was a significant increase in ePM2.5 in Indoor-Biomass and Outside-Biomass, compared to Gas. There was a significantly increased odds ratio (OR) for cough, wheezing and dyspnea in adults exposed to Indoor-Biomass (OR=2.93, 2.33, 2.59, respectively) and Outside-Biomass (OR=1.78, 1.78, 1.80, respectively) compared to Gas. Pulmonary function tests revealed both Non-Smoker-Biomass and Smoker-Gas individuals to have decreased %predicted-forced expiratory volume in the first second (FEV1) and FEV1/forced vital capacity (FVC) as compared to Non-Smoker-Gas. Pulmonary function tests data was inversely correlated with duration and ePM2.5. The prevalence of airway obstruction was 20% in both Non-Smoker-Biomass and Smoker-Gas subjects., Conclusion: Chronic exposure to biomass combustion is associated with increased prevalence of respiratory symptoms, reduced lung function and development of chronic obstructive pulmonary disease. These effects are associated with the duration and magnitude of exposure and are exacerbated by tobacco smoke., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The present paper aims to describe the spatial distribution of zooplankton copepods, their biomass and instantaneous secondary production, in Barra Bonita, a large eutrophic, polymitic reservoir (22 degrees 29' S and 48 degrees 34' W) on the Tietê River, of the Paraná basin. Sampling was carried out during two seasons: dry winter and rainy summer. Species composition, age structure and numerical density of each copepod species population were analyzed at 25 sampling stations. Secondary production was calculated for Copepoda, the dominant group in zooplankton communities, taking Calanoida and Cyclopoida separately. Copepoda represented the largest portion of the total zooplankton biomass, the dominant species being Notodiaptomus iheringi among the Calanoida and Mesocyclops ogunnus and Thermocyclops decipiens among the Cyclopoida. The production of Copepoda was higher during the rainy summer (23.61 mgDW.m(-3).d(-1) in January 1995) than during the dry winter season (14 mgDW.m(-3).d(-1) in August 1995), following the general pattern of abundance for the whole zooplankton community. Among the copepods, Cyclopoida production was higher than that of Calanoida, a pattern commonly observed for tropical lakes and reservoirs. Barra Bonita copepods are very productive, but there was a great degree of spatial heterogeneity, related to the physical and chemical conditions, particularly the level of nutrients and also to phytoplankton biomass.

This paper reports on a study involving an estimate of the biomass of rotifers, cladocerans, and cyclopoid and calanoid copepods found in reservoirs in different trophic conditions, comparing and relating numerical density data and pointing out differences between the dry and rainy seasons. In terms of numerical densities, both reservoirs were dominated by rotifers, although cladocerans represented a higher biomass in the oligotrophic environment in both seasons. In the eutrophic environment, higher biomass values were found for cyclopoids during the dry season and for cladocerans during the rainy one. Different biomass patterns were observed relating to both the trophic conditions and the rainy and dry seasons.

This paper deals with variations in biomass and in the production of Eichhornia crassipes (water hyacinth) in a eutrophic tropical reservoir. Net production was assessed by both a traditional method and a demographic approach. The initial biomass ranges from 96 g DW.m-2 to a maximum of 2027 g DW.m-2. Net production estimates varied greatly according to which method was used to calculate them (traditional: 20.6 ton DW.hectare-1.year-1, demographic: 226.9 ton DW.year-1).

This paper outlines the methods and results for monitoring forest change and resulting carbon emissions for the 1990-2000 and 200-2005 periods carried out over tropical Central and South America. To produce our forest change estimates we used a systematic sample of medium resolution satellite data processed to forest change maps covering 1230 sites of 20 km by 20 km, each located at the degree confluence. Biomass data were spatially associated to each individual sample site so that annual carbon emissions could be estimated. For our study area we estimate that forest cover in the study area had fallen from 763 Mha (s.e. 10 Mha) in 1990 to 715 Mha (s.e. 10 Mha) in 2005. During the same period other wooded land (i.e., non-forest woody vegetation) had fallen from 191 Mha (s.e. 5.5 Mha) to 184 Mha (s.e. 5.5 Mha). This equates to an annual gross loss of 3.74 Mha·y-1 of forests (0.50% annually) between 1990 and 2000, rising to 4.40 Mha·y-1 in the early 2000s (0.61% annually), with Brazil accounting for 69% of the total losses. The annual carbon emissions from the combined loss of forests and other wooded land were calculated to be 482 MtC·y-1 (s.e. 29 MtC·y-1) for the 1990s, and 583 MtC·y-1 (s.e. 48 MtC·y-1) for the 2000 to 2005 period. Our maximum estimate of sinks from forest regrowth in tropical South America is 92 MtC·y-1. These estimates of gross emissions correspond well with the national estimates reported by Brazil, however, they are less than half of those reported in a recent study based on the FAO country statistics, highlighting the need for continued research in this area. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Forest Research / Pesquisa Florestal Brasileira is the property of Brazilian Journal of Forest Research / Pesquisa Florestal Brasileira and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: This paper presents a proposal of sustainable management model alternative for electrification of remote communities in the Amazon region, considering the Brazilian regulation policy. This paper presents also a case study of the electrification in a river-dwelling community in the State of Pará, Brazil, within the scope of the Program for Electric Power Service Universalization in Brazil. The community shall be provided with electrification facilities through a small biomass-based power plant, directly firing residues produced by the local economic activity. The objective of the paper is to make a proposal for a sustainable management model that is suitable for the community’s isolation conditions, considering the high costs with operation and maintenance related to the supply for isolated consumers in small locations. A simulation is conducted for the operation of the small biomass-based power plant; the generation costs are determined; the legal aspects are analyzed; and a suggestion for the management model is presented. [Copyright &y& Elsevier]

Summary: Through the assessment of three decades of the Alcohol Program in Brazil, the paper shows that adequate public policies regarding biomass production can deliver direct benefits like energy security improvement, foreign exchange savings, and local employment generation, reduced urban air pollution and avoided CO2 emissions. Moreover, the paper shows that Brazilian produced ethanol has faced economies of scale, technical progress and productivity gains and is no longer dependent on subsidies to be competitive. The paper also examines the potential in Brazil for fostering other biofuels, namely biodiesel obtained from vegetable oils, as well as their implications on sustainable energy development. [ABSTRACT FROM AUTHOR]

This paper presents a detailed review of the energy potential from residual biomass for distributed generation in Brazil, presenting the potential by macro-region of the different types of residues generated in the agricultural, forestry, livestock, industrial and urban sectors. The focus of this research is to map and point out, through bibliographic research, the great potential of biomass in the Brazilian market for the production of biogas and consequently the use for electric power generation in the country and especially in the state of Paraná. Therefore, it should be emphasized that the methodology used is based on a bibliographic research from databases and recent research using a survey carried out by the ITAIPU Technological Park (PTI) in partnership with SENAI/PR, using the FIEP Observatories. As result, this research describes through data collection a favorable scenario for the technical feasibility of the use of biomass for the energetic use of biogas for power generation. The distributed generation of electricity from the use of biomass could help Brazil in the preservation of the environment as well as contribute to the diversification of the energy matrix, economic development and broadening access to energy in isolated communities. [ABSTRACT FROM AUTHOR]

Many simulation models that are used to assess the impact of mixed farming systems have a high level of complexity that is not suitable for teaching farmers about the impacts of their practices. In this paper, we present a model that was developed and used with farmers as a discussion support tool to address the impacts of farming management strategies on farm resources. We assumed that the characterization of biomass flows at the farm level would provide a simple framework for designing a discussion support tool for farmers. The study was carried out in the semi-arid region of Brazil, where areas of native vegetation of the Caatinga Biome have been reduced in recent decades due to population pressure. In this region, simulation models are not used to discuss the impact of practices. We decided that a model for this purpose should: (1) be simple enough to be used by farmers, (2) be consistent with existing data, and (3) take into account the three main biomass management strategies. The model we built simulates biomass exports (harvest, animal intake, clearing vegetation of Caatinga), imports (purchase of fodder), and returns (animal manure) for farms with different vegetation types (Cenchrus ciliaris, Sorghum bicolour, Opuntia sp. and Caatinga native vegetation). We used the model to compare three management strategies over a 15-year period and found that the strategy that allows for the preservation of Caatinga vegetation is less sensitive to bad years but results in a reduced herd size.We validated the use of this model by testing it with farmers. We found that farmers were interested in using the model as a learning (38%), management (33%), or prospective tool (24%). This study shows that the dynamic modeling of biomass flows provides a simple and operational framework to analyze the impact of farming systems on farm resources with farmers. Contrary to current dynamic biophysical models that are based on extensive experimental data, this model does not give accurate predictions but allows both farmers and researchers to learn the impacts of farming systems. The complexity of the model should be increased progressively as farmers improve their understanding of the underlying processes. [ABSTRACT FROM AUTHOR]

From July 2003 to June 2004, the physiographic characteristics of the ichthyofauna of the estuary of Saco da Fazenda were studied in four defined areas representative of the estuary. A total of 4502 individuals were captured, with 42 species, 35 genera, and 21 families. Engraulidae were the most abundant fish, and Cetengraulis edentulus dominated the captures. The species of occasional occurrence prevailed in the samplings and were represented mainly by juvenile individuals. The highest abundances occurred during the months of summer and autumn, in contrast with high biomasses in the spring and autumn; area IV contributed the largest captures. The richness indexes, diversity, and equitability presented similar flotation patterns, with high values in spring and summer. The Jaccard index revealed a greater similarity in the composition of the ichthyofauna in areas II and IV, while the lowest happened between I and IV, which is probably due to the different sizes of these areas. This paper clearly shows the relevance of this estuary, albeit strongly impacted, for recruitment of small fish mainly during summer and autumn months. [ABSTRACT FROM AUTHOR]

Planted pastures (mainly Brachiaria spp) are the most extensive land use in the cerrado (savannas of central Brazil) with an area of approximately 50 × 106 ha. The objective of the study was to assess the effects of pasture restoration on the N dynamics (net N mineralization/nitrification, available inorganic N and soil N oxide gas fluxes—NO and N2O), C dynamics (CO2 fluxes and microbial biomass carbon), and diversity of the soil bacterial community using denaturing gradient gel electrophoresis (DGGE) profiles. Sampling was done monthly on a farm in Planaltina, Goiás, Brazil (15°13′S, 47°42′W) from November 2001 to April 2002. Three areas of cerradão (dense cerrado) were converted to pasture (Brachiaria brizantha) in 1991, and after 8 years degradation was evident with the decreasing plant biomass production. Methods to restore these pastures were investigated for their sustainability, principally their effects on trace gas emissions. The pastures have been managed since 1999 as follows: 1) fertilized plot (N = 60 kg ha-1 yr-1, P = 12 kg ha-1 yr-1); 2) grass–legume plot, Brachiaria associated with a legume (Stylosanthes guianensis) with addition of P (12 kg ha-1 yr-1); and 3) a traditional plot without management. A fourth area of cerradão was converted to pasture in 1999 and was not managed (young pasture). Ammonium was the predominant inorganic N form in the soils (∼76 mg N kg-1) for all treatments throughout the study. In December 2001 a reduction in average soil N-NH4+ was observed (∼30 mg N kg-1) compared to November 2001, probably related to plant demand. All plots had high variability of soil N gases emissions, but during the wet season, the NO and N2O soil fluxes were near zero. The results of the water addition experiment made during the dry season (September 2002) indicated that the transition of dry to wet season is an important period for the production of N gases in the fertilized pasture and in the young pasture. Soil CO2 fluxes also increased after the water addition and the grass–legume plot had the highest increase in soil respiration (from ∼2 to 8.3 μmol m-2 s-1). The lowest values of soil respiration and microbial biomass carbon (∼320 mg C kg-1 soil) tended to be observed in the young pasture, because the superficial layer of the soil (0–10 cm) was removed during the conversion to pasture. Trace gas emissions measured after the water addition experiment corresponded to rapid changes in the soil bacterial community. The young pasture sample showed the lowest level of similarity in relation to the others, indicating that the bacterial community is also influenced by the time since conversion. This study indicates that the restoration technique of including Stylosanthes guianensis with B. brizantha increases plant productivity without the peaks of N oxide gas emissions that are often associated with the use of N fertilizers. Additionally, the soil bacterial community structure may be restored to one similar to that of native cerrado grasslands, suggesting that this restoration method may beneficially affect bacterially mediated processes. [ABSTRACT FROM AUTHOR]

This paper discusses emissions by power-dams in the tropics. Greenhouse gas emissions from tropical power-dams are produced underwater through biomass decomposition by bacteria. The gases produced in these dams are mainly nitrogen, carbon dioxide and methane. A methodology was established for measuring greenhouse gases emitted by various power-dams in Brazil. Experimental measurements of gas emissions by dams were made to determine accurately their emissions of methane (CH4) and carbon dioxide (CO2) gases through bubbles formed on the lake bottom by decomposing organic matter, as well as rising up the lake gradient by molecular diffusion. The main source of gas in power-dams reservoirs is the bacterial decomposition (aerobic and anaerobic) of autochthonous and allochthonous organic matter that basically produces CO2 and CH4. The types and modes of gas production and release in the tropics are reviewed. [ABSTRACT FROM AUTHOR]

In Brazil, logging in the Seasonally Dry Tropical Forest (SDTF) under management plans that include clear-cutting has increased in recent decades, and the structure, composition, diversity and functioning of the forest likely must have been affected. The aim of this study was to understand the growth dynamics of shrub–tree biomass (STB), species richness and vegetation structure as a function of regeneration time after clear-cutting (treatments), taking the Legal Reserve (40 years of regeneration) as reference. The study was carried out in 2018 at the Ramalhete Settlement, General Sampaio, in the state of Ceará. All plants with a circumference at breast height (CBH) ≥ 6 cm were identified and the CBH was measured across 42 sample plots (20.0 m × 20.0 m), using seven plots per treatment (3, 5, 8, 11 and 15 years after clear-cutting, and the Legal Reserve, 40 years of regeneration). The following were determined: STB (total and by species), density and basal area (by ecological group and diameter class), basal area (species of higher added value), diversity (Hill numbers), and the importance value index (IVI). It was found that during the early years (up to at least 11 years), many important forest characteristics related to the composition of the ecological groups and vegetation structure were strongly affected, and major impacts can be seen, the effects of which, however, decreased over time of regeneration, having almost no effect after 15 years. After 15 years following clear-cutting, the SDTF presented accumulated STB, species richness and structure similar to the area undergoing regeneration for 40 years. However, the small number of indicator species of more-preserved areas (even at T15 and T40) points out that management needs to be improved. However, promoting species of greater added value and determining whether the forest recovers its structure and diversity after successive cutting cycles also still need to be addressed. [ABSTRACT FROM AUTHOR]

Determining the period of weed coexistence with eucalyptus stands assists in the integrated management of weed competition, which reduces the application of herbicides, economic costs, and environmental damage. Therefore, the objectives of the present study were to evaluate the impact of a hybrid stand of Eucalyptus grandis × Eucalyptus urophylla trees on biomass production, the concentration and stock of macro and micronutrients, and the efficiency of nutrient utilization under different periods of coexistence with weeds. Our study is the first to report the impacts of weed management on the biomass and nutrients present in the leaves, branches, stembark, and stemwood at the time of mid-rotation (4.5 years old). The experiment was carried out in southern Brazil in the Pampa biome and followed a randomized block design, with three replications. The treatments consisted of increasing periods of coexistence with or control of weeds. The total biomass in the coexistence up to 378 days treatment was 53.7 Mg ha−1, and in the control treatment up to 168 days, it was 81.4 Mg ha−1, differing statistically. This reduction was in the order of 34%. The continuous presence of weeds led to a significant reduction in the production of wood and total biomass. The highest nutrient utilization efficiency (NUE) was observed for wood. The control of weeds for up to 168 days promoted greater productivity than controlling weeds for 378 days. This recommendation can be adopted by plantation managers for this region, reducing the amount of herbicide applied on the stand. [ABSTRACT FROM AUTHOR]

Age, growth, and maturity of the bluewing searobin Prionotus punctatus were studied to assess its stock status in southern Brazil. Total length compositions, weight, sex, and maturity stage were recorded from commercial landings, and ages were estimated from transverse sections of the sagittal otolith. The oldest observed specimen was a 12‐year‐old female. Females grew to a larger asymptotic length (L∞ = 384.4 mm) than males (L∞ = 311.7 mm) but at a slower instantaneous rate (kfemales = 0.41 year−1, kmales = 0.75 year−1). Reproduction occurred from spring to early fall. Females size‐ and age‐at‐maturity was estimated at 246.8 mm and 1.66 years, while males were at 237.2 mm and 1.38 years. Based on a statistical catch‐at‐age stock assessment, the spawning biomass declined 84% from 1976 to 2000 being classified as overfished and suffering from overfishing (B/Bmsy = 0.62; F/Fmsy >1). P. punctatus was regularly discarded by industrial fisheries before 2000 but suffered from high exploitation in the last decades. These results highlight the need for the species to be included in Brazil's fishery management plans. [ABSTRACT FROM AUTHOR]

Torrefaction has been investigated to improve the desirable properties of biomass as solid biofuel, usually used in natura as firewood in several countries. This paper has the main objective to present a broad characterization of the biomass Prosopis juliflora (P. juliflora), investigating its potential as a solid biofuel after its torrefaction process. The methodology was based on different procedures. The experimental runs were carried out at 230, 270, and 310 °C for 30 min, using a bench-scale torrefaction apparatus, with an inert atmosphere. In order to investigate the effect of temperature in constant time, torrefaction parameters were calculated, such as mass yield, energy yield, calorific value, base-to-acid ratio (B/A), and the alkaline index (AI). The physicochemical properties of the torrefied samples were determined and thermogravimetric analysis was used to determine the kinetic parameters at four different heating rates of 5, 10, 20, and 30 °C/min. Pyrolysis kinetics was investigated using the Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) isoconversional methods. Highly thermally stable biofuels were obtained due to the great degradation of hemicellulose and cellulose during torrefaction at higher temperatures. The highest heating value (HHV) of the samples varied between 18.3 and 23.1 MJ/kg, and the energy yield between 81.1 and 96.2%. The results indicate that P. juliflora torrefied becomes a more attractive and competitive solid biofuel alternative in the generation of heat and energy in northeast Brazil. [ABSTRACT FROM AUTHOR]

This paper focuses on an analysis of the energy mix profile and energy efficiency of the Brazilian dairy industry. It investigates dairies’ energy mix and energy efficiency and identifies some actions for a cleaner energy mix. Primary data from 37 dairy cheese-making establishments distributed among the Brazilian regions were obtained from online surveys. The results indicate that woodfuel plays a critical role, being the most used fuel in thermal energy generation, while diesel is dominant in electric generation. It also emphasizes that only 51% of the dairy establishments utilize electric energy generators. Other alternative biomass sources are still incipient in the sector, restricted to just 9.5% of the cases for thermal energy generation and no cases for electricity. Regarding the energy efficiency analysis, the results suggest dairies are more scale efficient than pure technical efficient. However, the dairies present a low energy efficiency level. There is no evidence that inefficiencies are differently distributed according to their size. These findings are important for government agencies, industry associations, scientists, universities and research institutes. High inefficiencies, regarding the use of electricity and thermal energy, are a key issue in sustainable bioenergy production. [ABSTRACT FROM AUTHOR]

Based on the general acceptance that greenhouse gases from biomass can provide a low carbon energy source, bioenergy pathways are being increasingly included in many countries renewable energy and emission reduction strategies. As a result demand for biomass is rising fast with several regions forecast to encounter major resource stresses over the coming decades. The bioenergy strategies of many countries rely heavily on future imported resource to balance their bioenergy resource demands. Applying a Biomass Resource Model to evaluate and forecast the types and potential availability of different categories of biomass resources from Brazil – a case study of a country with extensive biomass resources and export potential. This research evaluates Brazil's biomass potential to 2030, and analyses the levels of resource that may be available to export. The research finds that Brazil has extensive biomass resources that are potentially sufficient to both balance Brazilian total primary energy demand by 2030 and for Brazil to increasingly become a major exporter of resource for energy end uses. The paper also discusses the potential impact for global biomass trade, if countries such as Brazil were to adopt energy strategies that resulted in greater domestic use of their available biomass. The research's analysis shows that if the Brazilian Government were to adopt strategies to utilise a greater proportion of its resource for domestic energy, Brazil could export up to >25.8% less biomass by 2030 compared to forecast export levels based on Brazil's current policy framework. [ABSTRACT FROM AUTHOR]

In this paper we describe the use of space and feeding ecology of seven groups of golden lion tamarins observed for a total of 2,164 hr in Poço das Antas Reserve, Rio de Janeiro, Brazil. Relative to habitat availability in the home ranges of these groups, lion tamarins spent more time than expected in relatively undisturbed swamp forests and less time than expected in more degraded hillside and pasture habitats. Home range area was correlated with group biomass but not group size. Golden lion tamarins fed primarily on fruits and small animal prey, but relied heavily on floral nectar during seasonal periods of relatively low fruit availability. Compared to other New World monkeys, lion tamarins used larger home range areas and exhibited longer daily path lengths than would be predicted by group biomass alone. We suggest that this pattern of foraging and use of space may be explained by the relatively greater availability of cryptic prey and their microhabitats in forests that are flooded and/or have closed canopies than in forests that are in earlier stages of succession where prey may be more susceptible to desiccation during the dry season. Am. J. Primatol. 41:289–305, 1997. © 1997 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

[Display omitted] • Woody plant assemblages along forest regeneration had a higher occurrence of specialized traits and strategies. • Regenerating forest stands also supported a higher (30%) functional diversity of reproductive traits than old-growth stands. • Forest biomass and aridity correlated negatively with reproductive trait diversity. • The Caatinga dry forest regeneration as examined in the community-level plant reproductive context is marked by high resilience. • Aridity and chronic human disturbances did not alter the regeneration trajectory in the Caatinga dry forest. • The Caatinga dry forest regeneration, in the context of slash-and-burn agriculture, is traits-dependent. Tropical forest regeneration across old fields has been mainly described as a predictable sequence of functional plant assemblages in response to environmental filtering. However, the way plant reproductive diversity is organized along forest regeneration and how the reproductive profile of woody flora may impact regeneration have been poorly investigated. This paper examines the organization of plant assemblages throughout the regeneration of a Caatinga dry forest in the context of slash-and-burn agriculture with a focus on reproductive plant traits and strategies. We hypothesized a recovery and directional changes in specialist reproductive traits/strategies along forest regeneration but with aridity and chronic anthropogenic disturbances posing contrary forces to this recovery process. This study was carried out in a human-modified landscape of Caatinga dry forest in northeast Brazil. We compiled information on woody plant assemblages inhabiting a forest chronosequence consisting of 28 forest stands of varying age: 14 regenerating (4–50-yr old) and 14 old-growth forests. Woody plant assemblages along forest regeneration had higher occurrence of specialized traits and strategies, such as pollination by vertebrates (16.6%) and dispersion by animals (47.8%). Regenerating forest stands exhibited a higher occurrence of species with specialized floral size (19%) and pollination by vertebrates (26.5%) as compared to old-growth forests. Regenerating forest stands also supported a higher (30%) functional diversity of reproductive traits than old-growth stands. Biomass, aridity, and chronic anthropogenic disturbances affected a myriad of traits/strategies: pollination by birds and animal dispersion increased with increases in biomass while total functional diversity responded negatively; pollination by Sphingids and beetles negatively responded to aridity, while very large fruit size species negatively responded to chronic anthropogenic disturbances. Both forest biomass and aridity correlated negatively with reproductive trait diversity. The Caatinga dry forest regeneration suggests high resilience, no directional/predictable changes (although regenerating vs. old-growth differ in some traits) and aridity imposed to the successional mosaics as a driver. This pattern probably emerges conditioned by the reproductive traits posed by the plant species able to thrive in such stressful environments, including those species that persist through the entire regeneration process, i.e., the regeneration process is marked by high complexity and low predictive power. Although rapid recovery represents good news, the plant-assemblage reproductive profile imposed by disturbance-adapted species may drastically alter resource availability for a myriad of plant attendants (e.g., pollinators and thief) and, consequently, the complex/diverse plant-animal interactions typical of dry forests. This working hypothesis has both theoretical and applied implications in the context of dry forest regeneration in human-modified landscapes. [ABSTRACT FROM AUTHOR]

Fragmented tropical forest landscapes preserve much of the remaining biodiversity and carbon stocks. Climate change is expected to intensify droughts and increase fire hazard and fire intensities, thereby causing habitat deterioration, and losses of biodiversity and carbon stock losses. Understanding the trajectories that these landscapes may follow under increased climate pressure is imperative for establishing strategies for conservation of biodiversity and ecosystem services. Here, we used a quantitative predictive modelling approach to project the spatial distribution of the aboveground biomass density (AGB) by the end of the 21st century across the Brazilian Atlantic Forest (AF) domain. To develop the models, we used the maximum entropy method with projected climate data to 2100, based on the Intergovernmental Panel on Climate Change Representative Concentration Pathway (RCP) 4.5 from the fifth Assessment Report. Our AGB models had a satisfactory performance (area under the curve > 0.75 and p value <.05). The models projected a significant increase of 8.5% in the total carbon stock. Overall, the projections indicated that 76.9% of the AF domain would have suitable climatic conditions for increasing biomass by 2100 considering the RCP 4.5 scenario, in the absence of deforestation. Of the existing forest fragments, 34.7% are projected to increase their AGB, while 2.6% are projected to have their AGB reduced by 2100. The regions likely to lose most AGB—up to 40% compared to the baseline—are found between latitudes 13° and 20° south. Overall, although climate change effects on AGB vary latitudinally for the 2071–2100 period under the RCP 4.5 scenario, our model indicates that AGB stocks can potentially increase across a large fraction of the AF. The patterns found here are recommended to be taken into consideration during the planning of restoration efforts, as part of climate change mitigation strategies in the AF and elsewhere in Brazil. [ABSTRACT FROM AUTHOR]

This review investigates the effects of the Brazilian agriculture production and forestry sector on carbon dioxide (CO2) emissions. Residual biomasses produced mainly in the agro-industrial and forestry sector as well as fast-growing plants were studied. Possibilities to minimize source-related emissions by sequestering part of carbon in soil and by producing biomass as a substitute for fossil fuel were extensively investigated. The lack of consistency among literature reports on residual biomass makes it difficult to compare CO2 emission reductions between studies and sectors. Data on chemical composition, heating value, proximate and ultimate analysis of the biomasses were collected. Then, the carbon sequestration potential of the biomasses as well as their usability in renewable energy practices were studied. Over 779.6 million tons of agricultural residues were generated in Brazil between 2021 and 2022. This implies a 12.1 million PJ energy potential, while 4.95 million tons of forestry residues was generated in 2019. An estimated carbon content of 276 Tg from these residues could lead to the production of approximately 1014.2 Tg of CO2. Brazilian biomasses, with a particular focus on agro-forest waste, can contribute to the development of sustainable alternative energy sources. Moreover, agro-waste can provide carbon credits for sustainable Brazilian agricultural development. [ABSTRACT FROM AUTHOR]

Deforestation accounts for the majority of greenhouse gas emissions in developing countries. In Brazil, deforestation represents ~ 70% of the nation's greenhouse gas emissions. Among the main deforested vegetation, Cerrado (Brazilian savanna) occupies a prominent position as it is the second biggest biome in Brazil. Despite its importance, there are still few estimates of above and belowground biomass of Cerrado vegetation encompassing its structural and spatial complexity. Also, Cerrado holds a specific biodiversity that is normally undervalued and which is being lost in the fires of agricultural fronts. In this context, this study aimed to verify the relationship of the existing flora biodiversity in a cerrado stricto sensu with its aboveground biomass and carbon stocks. The possibility of a relationship between fine root mass and soil organic carbon content was also verified. The study area presented a total of 67 species and 798 trees (average: 1596 trees ha−1). The mean total aboveground biomass and carbon stocks were 77.08 Mg ha−1 and 38.54 Mg ha−1 respectively. Soil organic carbon stock (0–30 cm) was 8.51 Mg ha−1 whereas fine roots were 1.637 Mg ha−1. Total aboveground biomass presented a highly significant asymptotic relationship with biodiversity demonstrating its importance in reaching high biomass accumulation. A significant relationship between soil organic carbon content and fine root biomass was found making easier belowground biomass estimates. [ABSTRACT FROM AUTHOR]

Several hypotheses try to explain the factors that limit the distribution of tree species in wetlands. Among them, the stress-gradient hypothesis states that interspecific ecological interactions (facilitation and competition) vary inversely across abiotic stress gradients, with facilitation being more common under conditions of high abiotic stress than under more benign conditions. We investigated the effects of ecological interactions on the biomass of two native tree species, Crateva tapia (highly flood-tolerant) and Hura crepitans (low flood tolerant) exposed to different experimental flooding conditions in a greenhouse. Individual and paired plants were submitted for 120 days to four treatments: (1) non-flooding and non-ecological interaction; (2) flooding and non-ecological interaction; (3) non-flooding and ecological interaction; (4): flooded and ecological interaction. Flooding reduced biomass allocation in H. crepitans. C. tapia biomass was reduced by interspecific interaction with H. crepitans. Flood and interspecific ecological interactions together facilitated the accumulation of biomass in H. crepitans. Our results support the stress-gradient hypothesis, showing that in a flooded environment, the species with low tolerance to flooding (H. crepitans) is favored by the presence of other species. Additional tests with other species can confirm whether this is a pattern that helps explain the establishment of tree species in wetlands. [ABSTRACT FROM AUTHOR]

A significant part of fruit production is wasted annually, a material of high value without use, causing environmental and social damage. These residues from agro-industrial processes, or those that can no longer be used in the market, can be recycled and generate value-added products by pretreatments/hydrolysis. One of the important pretreatments is acid hydrolysis, which can produce xylooligosaccharides (XOS) from biomass, a product of great commercial value in the food and pharmaceutical markets, mainly due to its prebiotic potential. Bananas, oranges, and guava generate a large volume of waste and represent much of Brazil's fruit production. The dilute acid hydrolysis resulted in XOS production of 37.69% for banana peel, 59.60% for guava bagasse, 28.70% for orange bagasse, and 49.64% for restaurant residue. XOS were quantified by a liquid chromatograph system with a Bio-Rad Aminex HPX-87C column. The results show that, for this type of material and hydrolysis, the ideal conditions to produce XOS are high temperature, low time, and high acid concentration for banana peel residue (160 °C, 15 min, and 3% H2SO4), low temperature, low time, and high acid concentration for guava bagasse (100 °C,15 min and 3% H2SO4), high temperature and acid concentration with low time for orange bagasse (160 °C,15 min and 3% H2SO4) and high temperature and time and high acid concentration for restaurant waste (160 °C, 55 min and 3% H2SO4). This study identified acid hydrolysis conditions that maximized XOS production with a low amount of xylose production using agro-industrial and food residues, also showing the high potential of the chosen residues through the high yields of XOS production. [ABSTRACT FROM AUTHOR]

Energy demand has increased worldwide, and biomass burning is one of the solutions most used by industries, especially in countries that have a great potential in agriculture, such as Brazil. However, these energy sources generate pollutants, consisting of particulate matter (PM) with a complex chemical composition, such as sugarcane bagasse (SB) burning. Controlling these emissions is necessary; therefore, the aim was to evaluate PM collection using a rectangular Venturi scrubber (RVS), and its effects on the composition of the PM emitted. Considering the appropriate use of biomass as an industrial fuel and the emerging need for a technique capable of efficiently removing pollutants from biomass burning, this study shows the control of emissions as an innovation in a situation such as the industrial one with the use of a Venturi scrubber in fine particle collection, in addition to using portable and representative isokinetic sampling equipment of these particles. The pilot-scale simulation of the biomass burning process, the representative sampling of fine particles and obtaining parameters to control pollutant emissions for a Venturi scrubber, meets the current situation of concern about air quality. The average collection efficiency values were 96.6% for PM> 2.5, 85.5% for PM1.0–2.5, and 66.9% for PM< 1.0. The ionic analysis for PM< 1.0 filters showed potassium, chloride, nitrate, and nitrite at concentrations ranging from 20.12 to 36.5 μg/m3. As the ethanol and sugar plants will continue to generate electricity with sugarcane bagasse burning, emission control technologies and cost-effective and efficient portable samplers are needed to monitor particulate materials and improve current gas cleaning equipment projects. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)