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This paper is aimed to develop a hybrid model (PCA-ANN) to predict the extractive content in eucalyptus wood clones. The input variables to the virtual analyzer are planting parameters available from the forest inventory, therefore the prediction does not rely on laboratory analysis of the wood samples, affording a quick estimate of the extractive contents. This study further bridges the literature gap on the investigation of the cause of variability of extractive content in eucalyptus wood. The PCA-ANN was identified from experimental data to predict and monitor the extractive content, since laboratory measurements can take several days and become available only after wood processing. The experimental data contained information on ten species of eucalyptus clones from five regions in the extreme south of Bahia, Brazil. Principal Component Analysis (PCA) firstly assessed the impact of planting variables on the extractives content. The variability of the data was represented by eight principal components and the variables that mostly contribute to the extractive content are: potential acidity, iron, saturation of aluminum, magnesium, pH, base saturation, remaining phosphorus, zinc, manganese and copper. The artificial neural network (ANN) with the 8 principal components in the input layer showed that the PCA could effectively reduce the dimensionality of the data. For practical purposes, though, the ANN with 10 input variables and 16 neurons in the hidden layer, presenting an average relative deviation of 1.5%, is recommended. The prediction of the extractive content is essential to allow preventive management practices toward the improvement of yield and quality of the cellulosic pulp. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic is the most profound crisis of the twenty-first century. The SARS-CoV-2 virus was first registered in Brazil on March 2020, and its social and economic repercussions have been catastrophic. This paper investigates how to apply model predictive control (MPC) algorithms to plan appropriate social distancing policies that mitigate the pandemic effects. We consider MPC applications for the states of Bahia and Santa Catarina (Brazil), two regions of very different social and cultural demographics. We use Susceptible-Infected-Recovered-Deceased model to describe the pandemic dynamics in these two states, for which parameters are identified using a constrained optimization procedure. The control input to the process is a social isolation guideline passed to the population. Two MPC frameworks are developed and discussed: (a) a centralized approach, which coordinates a single predictive control policy for both states, and (b) a distributed strategy, for which a single MPC problem is solved for each state. We provide a series of simulation results in order to illustrate and compare the results obtained with both these MPC strategies. Discussions are drawn regarding the effectiveness of MPC to guide social distancing measures during pandemics and which approach (distributed, centralized) is more convenient, regarding different conditions. [ABSTRACT FROM AUTHOR]

From 2015 to 2016, an epidemic of births of children with Congenital Zika Virus Syndrome emerged in Brazil, and the state of Bahia concentrated the highest incidence of cases. The official health guidelines recommended that the affected children and their families should be supported by interdisciplinary teams of early intervention. This paper aims to deepen the comprehension of regulation and affective-semiotic mediation processes involved in the early intervention with children with Congenital Zika Virus Syndrome and their families. It focus on the experiences of a professional interviewed in a public health service in Salvador, Bahia – Brazil, through narrative analysis and the theoretical-methodological foundations of Cultural Psychology of the Semiotic Dynamics. These approaches allowed the understanding of the processes of construction of meanings, symbolic action and affective-semiotic regulation. The care of Congenital Zika Virus Syndrome children by professionals relates to disquieting experiences, inter subjectivity, meaning construction, affections and symbolic actions. These dynamic processes allowed the professional to better adapt to regulation and affective-semiotic mediation, as well as her own performance in face of children and their families. This analysis emphasizes the reflections of health care practices and their repercussions in the quality of the assistance. [ABSTRACT FROM AUTHOR]

Censuses and other surveys responsible for gathering socioeconomic data are expensive and time consuming. For this reason, in poor and developing countries there often is a long gap between these surveys, which hinders the appropriate formulation of public policies as well as the development of researches. One possible approach to overcome this challenge for some socioeconomic indicators is to use satellite imagery to estimate these variables, although it is not possible to replace demographic census surveys completely due to its territorial coverage, level of disaggregation of information and large set of information. Even though using orbital images properly requires, at least, a basic remote sensing knowledge level, these images have the advantage of being commonly free and easy to access. In this paper, we use daytime and nighttime satellite imagery and apply a transfer learning technique to estimate average income, GDP per capita and a constructed water index at the city level in two Brazilian states, Bahia and Rio Grande do Sul. The transfer learning approach could explain up to 64% of the variation in city-level variables depending on the state and variable. Although data from different countries may be considerably different, results are consistent with the literature and encouraging as it is a first analysis of its kind for Brazil. [ABSTRACT FROM AUTHOR]

This paper aims to assess the sustainability of coffee production in Brazil by a framework at the farm level. The framework developed comprises four dimensions of sustainability structured from the literature review. Primary data were collected from 20 coffee farms selected from the most producing communities in the Planalto de Vitória da Conquista locality, sited in Centro-Sul Baiano middle region at the Bahia state. The main environmental issues identified related to coffee farmers are inadequate management of water consumption, influenced by the lack of knowledge about irrigation techniques in some cases, and the use of synthetic fertilizers and pesticides. The economic evaluation of the activity revealed a low index of producers belonging to a class organization. In social aspects the issues are low level of technical/technological instruction for coffee producers, temporary workers are often used, the old age of most producers, the lack of family succession for the activity, low incomes, the high number of temporary workers, and the absence of the worker gains. As for the technical dimension, only half of the farmers invest in innovation, which causes high obsolescence of their equipment and machinery and a low participation rate in training courses. In the environmental dimension, the farmers return the packages of pesticides to the stores where they bought them. In the technical dimension, most farmers perform soil analysis. Besides addressing the identified challenges, the initiatives can help achieve the Sustainable Development Goals, especially the 9th, 12th, and 13th. [ABSTRACT FROM AUTHOR]

Small-scale mining is an important source of income for many communities worldwide. However, many small-scale mining enterprises lack good management and mining practices and the limited funds available for exploration are often allocated inefficiently. This paper introduces a method of comparable values: a practical, low-cost and effective method for prioritization and selection of exploration targets in small-scale mining. The proposed method combines local geological mapping with a geological uncertainty assessment tool that indicates the risk associated with geological uncertainty for each target. By properly selecting exploration targets, small-scale miners can reduce the project risks and maximize the value resulting from investment that is more effective in exploration. The method of comparable values was applied to a small-scale project in a block of six manganese-rich claims in the state of Bahia, Brazil. The proposed method resulted in proper target selection with a time reduction of 50% and a cost savings of 76% when compared with those of traditional geological mapping work. [ABSTRACT FROM AUTHOR]

Tillandsia (Bromeliaceae) species have high endemism, and due to their strong ornamental potential, predatory extraction is threatening the extinction or drastic population reduction of many of them. In light of this scenario, it is necessary to find strategies for the conservation of these endangered species. The objective of this study was to evaluate two seed preservation strategies (freezing at − 5 °C and cryopreservation at − 196 °C) for 20 Tillandsia species occurring in the state of Bahia. We initially evaluated the morphometry, thousand-seed weight, and water content, followed by tests of germination and desiccation. After selecting the best result of the germination test (Germitest paper and incubation at 30 °C) and desiccation (3 h on silica gel), we established conservation tests utilizing two temperatures (freezing at − 5 °C and liquid nitrogen at − 196 °C), with storage times of 1, 7, 30, 180 and 450 days. Analysis of variance indicated that the 20 species had different behaviors when submitted to the two temperatures and different storage times. After 450 days there was a reduction in the germination percentage and germination speed index (GSI) of all the species studied when the seeds were preserved in the freezer. The storage in liquid nitrogen was efficient for the preservation of Tillandsia seeds when dried to a moisture content of approximately 7%. Our results support the establishment of a cryobank for Tillandsia to conserve these endemic species. [ABSTRACT FROM AUTHOR]

The article offers information on the 2008 Institute Of Electrical and Electronics Engineers/International Federation for Information Process IEEE/IFIP Network Operations and Management Symposium at Salvador in Bahia, Brazil from April 7-11. Topics included pervasive management, the use of machine learning algorithms for performance degradation, and cognitive radio networks. The symposium featured speakers include Roberto Saracco, Ian F. Akyildiz, and Luiz Fernando.

The purpose of this paper is to provide an analysis and application of the indexes of water-use conflict in water resources management (i) and planning (i) for the Grande river basin, aiming at identifying potential water-use conflicts and thus providing a basis for the water resources management organization of Bahia state, Brazil. In order to apply the indexes, the minimum reference outflow (Q) and the long-term average streamflow (Q) were estimated. Water demand was obtained from the water grant database from the Institute of the Environment and Water Resources of the State of Bahia. The results showed that in six stream segments of the basin, the legal water-use grant limit was exceeded. Some advantages of using these indexes are the possibility of assessing water scarcity at a river segment level and the fact that they provide a spatial analysis of potential conflicts in a basin. The analysis of water availability at the drainage segment level allows the management organization to act locally for the mitigation of water-use conflicts or to plan solutions for imminent conflicts. [ABSTRACT FROM AUTHOR]

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recent debate has contrasted two conservation strategies in agricultural landscapes; either 'land sparing' farm development combining intensive production practices with forest set-asides, or 'wildlife-friendly' farming with greater on-farm habitat value but lower yields. We argue that in established mosaic landscapes including old cacao production regions where natural forest has already been reduced to relatively small fragments, a combination of both strategies is needed to conserve biodiversity. After reviewing the evidence for the insufficiency of either strategy alone if applied to such landscapes, the paper focuses on the cacao production landscape of southern Bahia, Brazil, once the world's second largest cacao producer. Here, small remaining areas of Atlantic Forest are embedded in a matrix dominated by traditional cacao agroforests, resulting in a landscape mosaic that has proven favorable to the conservation of the region's high biodiversity. We show that current land use dynamics and public policies pose threats but also offer opportunities to conservation and describe a three-pronged landscape conservation strategy, consisting of (i) expansion of the protected areas system, (ii) promotion of productive yet biodiversity-friendly cacao farming practices, and (iii) assistance to land users to implement legally mandated on-farm reserves and voluntary private reserves. We discuss recent experiences concerning the implementation of this strategy, discuss likely future scenarios, and reflect on the applicability of the Bahian experience to biodiversity rich cacao production regions elsewhere in the tropics. [ABSTRACT FROM AUTHOR]

This paper depicts how an Afro-Brazilian carnival group turned community development organization addresses socioeconomic inequalities by educating a traditionally marginalized population as part of their larger goal of the preservation of black culture and full citizenship. Specifically, it examines the theory and practice of interethnic pedagogy, a unique approach to critical pedagogy specifically focused on incorporating the experiences and values of subaltern groups. Through ethnographic passages and analysis it examines their work in formal education at Escola Criativa Olodum in Salvador, Bahia and shows how Afro-Brazilian teachers, students and administrators engage in learning experiences while they strive to understand and redefine their own educational processes and outcomes. Lastly, through the lens of racial formation theory, it attempts to explain how these educators and activists periodically adjust their methods and considers their potential impact on Brazilian society. [ABSTRACT FROM AUTHOR]

Background: This paper reports findings on Alcohol Consumption-Abuse (ACAb) in Bahia, Brazil, a research setting characterized by racial/ethnic and socioeconomic diversity.Methods: A household survey was conducted with a sample of 2,302 adults. ACAb was defined as daily intake of more than two units of beverage, with drunkenness, or weekly binge drinking plus episodes of drunkenness, or any use of alcoholic beverages with frequent drunkenness, with failed attempts to stop drinking.Results: The rate of 12-month prevalence was 7%, with an overall male: female ratio of 6:1. A positive association of ACAb prevalence with education and social class was found. Male gender and higher socio-economic status were associated with increased odds of ACAb. No relationship was found between ethnicity and ACAb. Stratified analysis yielded consistent gender effects, throughout all strata of independent variables. A strong interaction of gender (male) and social class (upper class) was found for Mulattos and Morenos (maximum Prevalence rate=9.04).Conclusion: Interaction patterns found defy simple generalizations based on class, ethnicity, and gender considered alone. [ABSTRACT FROM AUTHOR]

Insecticide resistance is usually associated with fitness costs. The magnitude of the fitness costs is affected by environmental and ecological factors. Here, we explored how host plants could affect fitness costs associated with insecticide resistance. Initially, spinetoram-resistant and susceptible strains of Spodoptera frugiperda were selected using a F2 screen from a population collected in São Desidério, Bahia State, Brazil. In addition to the RR and SS strains, fitness costs were also assessed for a heterozygous strain (RS). Life-history traits were evaluated to estimate population growth parameters of each strain feeding on corn, soybean, and cotton plants. The relative fitness of the RR strain was 1.06 higher compared to the SS strain on corn plants, while in soybean and cotton plants these values were 0.84 and 0.67 lower, respectively. The relative fitness of the RS strain was similar to the SS strain regardless of the host plant, suggesting a recessive fitness cost. No differences were found between the strains fed on corn plants. The larval development time was greater for the RR strain fed on soybean and cotton plants compared to the RS and SS strains. Low survival rate and fecundity of the RR strain were found when larvae fed on soybean and cotton plants. The results of this study showed that fitness costs of spinetoram resistance in S. frugiperda depend on the host plants that S. frugiperda larvae fed on. Such information can be used to design resistance management strategies considering the host plants of the agricultural landscape. [ABSTRACT FROM AUTHOR]

Brazilian soybean is mainly grown in the Cerrado, the South American Savannah. We report epidemiological studies of soybean target spot (STS), caused by Corynespora cassiicola in two Cerrado regions in the Federal District (DF) and the state of Bahia (BA), relating the environmental parameters with disease intensities. Here we: i) characterize the field response of soybean cultivars to STS and compute their respective latent periods; ii) relate STS severity to yield; and iii) verify the cross-reaction of C. cassiicola isolates of soybean and cotton to each of these hosts. Ten commercial soybean cultivars were cultivated in DF and BA fields. Additionally, the cv. reactions were studied in greenhouse assays in the spring/summer and autumn/winter seasons. Precipitation and relative humidity were higher in DF than in BA, whereas the temperature was cooler with fewer extremely hot days. Greater STS intensity was observed in DF, reaching 48% incidence and 19% severity. Fungicide applications reduced disease only in the DF trial. Cultivars were separated into four groups: highly susceptible, susceptible, moderately resistant, and resistant. Higher disease severities were recorded in the spring/summer than in the autumn/winter. Length of latent periods correlated with the cv. response to STS and climate conditions. Environmental differences were the probable causes for the lower disease levels recorded in the BA fields and in the autumn/winter trial. A negative relationship was established between severity and yield. In the cross-inoculation studies, isolates of soybean and cotton were able to infect both hosts, but aggressiveness correlated with the host of origin. [ABSTRACT FROM AUTHOR]

Most of the genus Piriqueta occur in Brazil (39 out of 45 species), with a center of distribution in Bahia State. In this study, we conducted a palynological investigation of 20 heterostylous (distylous) species of the genus Piriqueta, including specimens from both floral morphs of 13 species. Pollen grains were examined, measured, and illustrated by using light and scanning electron microscopy. Pollen morphology was described in terms of shape, size, aperture, and exine ornamentation. Morphometric data were subjected to principal component analysis and hierarchical clustering. Examination revealed pollen grains arranged in monads, isopolar, 3-colporate, with great variability in shape (prolate, subprolate, prolate spheroidal, oblate spheroidal, or suboblate), endoaperture lalongate, polar area small or very small, exine ornamentation most commonly microreticulate or reticulate, sometimes perforate, sexine usually thicker than nexine. Piriqueta sulfurea was an exception, presenting verrucate exine ornamentation. Brevistylous pollen grains were larger in diameter in 75% of the specimens analyzed, whereas mostly longistylous pollen had larger colpi and smaller polar area, but there is no consistent pattern of variation from a specific morph. Even so, those variation underscore the importance of indicating the floral morphs used or, whenever possible, encompassing all existing morphs in pollen descriptions of heterostylous species. [ABSTRACT FROM AUTHOR]

In southeast Brazil, heavy precipitation events during the summer trigger floods. These disasters are responsible for most loss of lives. In November and December 2021, the northern area of Minas Gerais and the southern part of Bahia were affected by periods of very heavy rain and intense floods. Heavy precipitation contributed to unusually high soil saturation that favored floods that claimed lives. Estimated losses totaled about $3.1 billion U.S. dollars from November to December 2021. Therefore, this study: 1. evaluates the meteorological conditions in November–December 2021, in particular from December 22 to 29, when it rained up to 300 mm above average in this region, 2. analyzes the floods, exacerbated by extreme rainfall events earlier in November and December, and 3. discusses monitoring and issuing risk alerts of these disasters by government agencies that helped minimize damage and property loss and reduce fatalities. [ABSTRACT FROM AUTHOR]

In the cacao growing region of Bahia, Brazil, there are large areas of coastal plain soils, which normally do not support cacao cropping because of their adverse chemical and physical limitations. The main objectives of this work were to evaluate growth, photosynthesis, antioxidative metabolism, and gene expression in young plants of CCN 51 cacao genotype grown in coastal plain compacted soil, with location and phosphorus limitation. A cohesive yellow oxisol was placed in polyvinyl chloride tubes with 0.24 m (height) × 0.1 m (internal diameter). The tubes were subdivided into three rings of 0.08 m height connected with tape. In the upper and lower rings soil density was maintained at 1 kg dm−3. In the lower ring, two levels of soil P (low—200 mg dm−3 soil and ideal—400 mg dm−3 soil) were evaluated. In the middle ring five soil densities (1; 1.3; 1.4, 1.5, and 1.7 kg dm−3) were maintained. Changes were observed in the leaves number, leaf area and root dry biomass. There were variations in the activity of dismutase superoxide, catalase, ascorbate peroxidase and guaiacol peroxidase enzymes, involved in antioxidative leaf and root metabolism. Changes in the expression of the Cu–Zn–sodcyt, Cu–Zn–sodchl and per-1 gene transcripts were observed. Mechanical stress promoted by soil compaction, associated to variations in dose and P location, reduced the root length of the young cacao plants in relation to the volume, increased its diameter in the compacted layer and decreased the activity of most of the enzymes and expression of genes related to antioxidative metabolism, mainly in root level. [ABSTRACT FROM AUTHOR]

Purpose: Small mammals are important reservoirs of ticks and their pathogens in nature. However, studies reporting these associations are still rare in Brazil. In the present study, we investigated the presence of Rickettsia DNA in ticks parasitizing rodents and marsupials captured in different areas throughout the Atlantic rainforest biome, Bahia, Northeastern (NE), Brazil. Methods: The study was conducted in five municipalities within of the Atlantic Forest biome, Bahia state, in NE Brazil. Two campaigns were done in each municipality. For host captures Sherman and Tomahawk traps were used, and pitfall traps. After being captured, the hosts were anesthetized and their entire body examined for ticks. When ticks were detected, they were manually removed and stored in eppendorf tubes (1.5 ml) containing absolute PA ethanol for future laboratory analysis (identification of ticks and detection of Rickettsia spp.). Results: A total of 609 mammals were captured. Overall, 208 ticks of the genus Amblyomma and Ixodes were collected: A. ovale, I. loricatus and A. varium. Rickettsia DNA was detected in A. ovale and it was 99–100% of identity to the sequence deposited in GenBank as Rickettsia parkeri strain Atlantica rainforest. Conclusion: These results suggest that R. parkeri strain Atlantic rainforest occurs in the region, and A. ovale is likely the vector. [ABSTRACT FROM AUTHOR]

When performed without technical criteria, the rapid expansion of irrigated agricultural frontiers can result in overexploitation of water, causing worrying impacts on the balance of agroecosystems. This study proposes a model applied to the state of Bahia, to estimate the water demand of areas irrigated by a central pivot, in order to contribute to information that will subsidize the inspection and planning of water resources in the promotion of sustainable agriculture. The irrigated areas were identified and measured by photointerpretation using orbital images from the Landsat-8 satellite. With a historical series of data, the reference evapotranspiration was calculated and monthly water balance was elaborated. The data obtained were spatialized by kriging, and with punctual values of water deficit (mm), the water demand of the irrigated perimeter of the equipment was estimated. The results were described considering strategic planning units, proposed from municipalities, hydrographic basins and biomes. A total of 4075 pivots were quantified, covering an irrigated area of 265,896.30 ha and with an average annual consumption of 1,333,473,208.02 m3 of water. Areas of high demand were identified, especially in the western region of Bahia, which includes the hydrographic basin of the São Francisco River and the Cerrado biome, concentrating 80.85% and 75.47% of the state water demand for pivots, respectively. Considering possible points of water vulnerability and continuity of this expansion, the results provide the primary information needed to encourage the adoption of public policies aimed at the management of water resources. The study method proposes guidelines that condition the application in any region of interest in the world. [ABSTRACT FROM AUTHOR]

Based on a mixed-methods study involving triad tasks and ethnobiological models, we analyze local categories and knowledge of key ethnospecies of fish exploring partial overlaps between artisanal fishers' and academic knowledge in a fishing community in northeast Brazil. We argue that fishers' and academic knowledge overlaps may provide common ground for transdisciplinary collaboration, while their partiality requires reflection on epistemological and ontological differences. Here, we show how knowledge of artisanal fishers can complement academic knowledge and bring about tensions that need to be addressed through intercultural dialogue. By integrating a general philosophical framework of partial overlaps with a mixed-methods study on fishers' knowledge, we show how ethnobiology can contribute to reflective and empirically-grounded transdisciplinary practices. [ABSTRACT FROM AUTHOR]

Environmental and human health risk analyses of contamination by toxic elements in soil are important tools to manage remediation initiatives or population resettling. In Brazil, a primary lead smelter operated in Bahia state from 1960 to 1993 generating several environment and health concerns. This work presents an analysis of the estimated ecological and human health risk for the region around the smelter. Concentration data from three studies were used to evaluate ecological and health risk indexes. Geostatistical analysis using maps identified a high concentration of potentially toxic elements: Pb, Cd and Zn around the chimney of the old smelter, exceeding the regulatory limits for industrial soil. The soil pollution and ecological risk analyses showed high values around the chimney of the old plant. The analysis of risk to human health showed that the risk for disease through soil contamination by Cd and Zn is low and non-existent around the old plant. However, the risk for disease through soil contamination by Pb is very high for children and moderately high for adults around the old plant. It is estimated that more than 7000 people are at risk in this region due to the toxic elements in the soil (about 12% of the population of the city). Due to the pollution and the ecological and health risks of the contaminated soil in the Santo Amaro region, the authorities should urgently undertake remediation and resettlement programs for the population of the region. [ABSTRACT FROM AUTHOR]

The granting of permits for the use of water resources has been legislated to ensure adequate access to water for all user sectors. However, this management instrument may not effectively perform quantitative control over the granting process, and permits for flows greater than the water availability may be granted and thus are not always representative of the actual abstractions. Therefore, the present study aimed to develop a methodology to optimize the use of water in shared management schemes under conflict conditions. The proposal is based on the initial evaluation of water availability conditions within a legal plan, in which the flows that consider all uses are associated with the annual run-of-river water availability, and, subsequently, for the segments where the demands are higher than the availability, on the analysis of water availability condition in an operational plan. At the operational level, the demands are characterized by the permitted flows that consider all uses except those corresponding to irrigation activities, which are estimated based on the flows required by the equivalent hectares. In this plan, the availability is considered on a monthly run-of-river basis and with the presence of flow-regulation reservoirs. For the application of the proposed methodology, the Rio Branco basin in western Bahia State is considered. The results indicated that management bodies require extensive knowledge of the actual abstractions corresponding to the permits granted, the potentialities of considering the minimum monthly run-of-river water availability and potential water availability of the basin under regulated-flow conditions, changes in cropping calendars and the use of deficit irrigation under conditions with conflicts over water use. [ABSTRACT FROM AUTHOR]

We investigated the relation between the spread, time scale, and spatial arrangement of dengue in Bahia, a Brazilian dry climate region, for the period 2000 to 2009. The degree of cross-correlation is calculated for 15 economic regions. We propose a multiscale statistical analysis to datasets of dengue cases in order to verify the effect of infection dispersal on the economic regions from the metropolitan region of Salvador. Our empirical results support a significant and persistent cross-correlation between most regions, reinforcing the idea that economic regions or climatic conditions are non-statistically significant in the spread of dengue in the State of Bahia. Our main contribution lies in the cross-correlation results revealing multiple aspects related to the propagation of dengue in dry climate regions. [ABSTRACT FROM AUTHOR]

The distribution of natural radiation from Brazilian beach sands was studied using gamma-ray spectrometry. While in most of the regions studied the dose due to external exposure to gamma-rays, proceeding from natural terrestrial elements, are within the values 0.3 and 1.0 mSv/year, some sand samples from Bahia, Rio de Janeiro and Sao Paulo states present higher radioactivity levels due to the presence of monazite and zircon, exceeding the world average value for external exposure due to naturally occurring radionuclides. [ABSTRACT FROM AUTHOR]

Ferns and lycophytes are plants with great diversity in tropical and subtropical regions, mainly in rain forests. In Brazil, the biome with the largest number of ferns and lycophytes species is the Atlantic Forest. However, studies on the distribution patterns of these species throughout the biome few and specific some regions. To reduce this knowledge gap, our work investigated the key areas of richness and endemism for species of ferns and lycophytes occurring in the Brazilian Atlantic Forest and assesses the effectiveness of protected areas for protecting this biodiversity. We registered 939 species, distributed among 39 families and 140 genera. We established four regions (centres) with a high number of species designated as: Bahia, Espinhaço/Caparaó, Serras do Mar/Mantiqueira and Southern centres. For endemism, we identified six relevant areas, all within the proposed richness centres. We found that 73.4% of the species occur within protection areas. The percentages of endemic and threatened species occurring within the limits of these areas correspond to 65.5% and 50.66%, respectively. The patterns of richness and endemism are directly related to the topographic and climatic characteristics that make up the environmental heterogeneity of the Brazilian Atlantic Forest. [ABSTRACT FROM AUTHOR]

Purpose: Fate factors, for freshwater eutrophication, represent the route of a limiting-nutrient, phosphorus or nitrogen, and their degradation in the environment. Their value may vary according to the location and emission season; that is, they are site and temporal dependent. In this study, phosphorus fate factors for the freshwater eutrophication impact category were estimated in a native scale of state hydrographic units (SHU), considering its variability and applied in a case study for one hydrographic basin in the state of Bahia, Brazil. Methods: The fate model considered the phosphorus removal processes of advection, retention, and agricultural and domestic water use, based on national databases (Geonetwork, HidroWeb, SAR, and SNIS). Heat maps and correlation networks allowed the assessment of fate factors' spatiotemporal variability. The new generated fate factors were qualitatively and quantitatively assessed, then further applied in a case study of buffalo milk production at Leste SHU to determine the regionalization effects on the freshwater eutrophication potential impact. Results and discussion: This study reconfirmed the spatial and temporal variability of the fate factors. The fate factor values found, in this study, for Pardo SHU are similar to those estimated with the non-regionalized data used by the adopted model, being within the range of 0 to 20 days. However, the fate factors for De Contas and, mainly, for Leste were underestimated, reaching a value up to five times higher, indicating that the model's proposed changes impacted the final result. The temporal differentiation was mainly determined by periods of higher and lower water availability. Advection processes inversely determined the fate factors, and the phosphorus removal by retention processes became more prominent when the water availability was lower. On the other hand, the role of phosphorus removal through water use was minimum. Water availability was the largest contributor to the sensitivity analysis, followed by the total freshwater volume. Conclusion: The fate modeling adopted in this study, with the use of data from national databases and native resolution, gave a more precise and detailed analysis perspective of the phosphorus fate in Brazilian SHUs, setting up site- and temporal-specific fate factors. Besides, this study provides a further understanding of the fate factors establishment by analyzing their relationship with the respective input parameters and highlighting one of the used model's weaknesses: the estimation of phosphorus removals instead of phosphorus load underestimates the true freshwater eutrophication potential. [ABSTRACT FROM AUTHOR]

The present study evaluated the influence of land use and occupation on water quality indices (WQI); the WQI developed by the National Sanitation Foundation (NSF), the WQI adapted by the Environmental Company of the São Paulo State (CETESB), WQI proposed by Bascarón and the Canadian Council of Ministers of the Environment (CCME) WQI, obtained for watersheds located in the Eastern Water Planning and Management Region (BA). The study also analyzed the divergences and similarities of these WQI methods. Water quality data were obtained from the Monitoring Program (Monitora) of Environment and Water Resources Institute of Bahia (INEMA), covering the period from 2008 to 2015, at thirteen (13) sampling sites, with quarterly collections, as well as land use and occupation data. The influence of land use and occupation on water quality indices was assessed by principal component analysis (PCA). The PCA showed that urban and agricultural/pasture areas were influencing factors on water quality variables, such as total phosphorus, biochemical oxygen demand, total nitrogen, turbidity total residues and consequently lower WQI values in the Cachoeira watershed. Among the tested methods to evaluate the water quality of watersheds in the study area, the most similar were the NSF WQI, CETESB WQI, and Objective Bascarón WQI. [ABSTRACT FROM AUTHOR]

COVID-19 is affecting healthcare resources worldwide, with lower and middle-income countries being particularly disadvantaged to mitigate the challenges imposed by the disease, including the availability of a sufficient number of infirmary/ICU hospital beds, ventilators, and medical supplies. Here, we use mathematical modelling to study the dynamics of COVID-19 in Bahia, a state in northeastern Brazil, considering the influences of asymptomatic/non-detected cases, hospitalizations, and mortality. The impacts of policies on the transmission rate were also examined. Our results underscore the difficulties in maintaining a fully operational health infrastructure amidst the pandemic. Lowering the transmission rate is paramount to this objective, but current local efforts, leading to a 36% decrease, remain insufficient to prevent systemic collapse at peak demand, which could be accomplished using periodic interventions. Non-detected cases contribute to a ∽55% increase in R0. Finally, we discuss our results in light of epidemiological data that became available after the initial analyses. Low-resource settings can face additional challenges in managing the COVID-19 pandemic. Here, the authors use mathematical modelling to investigate transmission in the state of Bahia, Brazil, and quantify control measures needed to prevent the hospital system becoming overwhelmed. [ABSTRACT FROM AUTHOR]

In semiarid region of Irecê, state of Bahia, Brazil, there are superficial elongated strips in form of lateritic crust derived from hydrothermal weathering of sulfide known as "gossans" with heavy metals anomalies. Thus, this study aimed to evaluate the presence and concentration of metals As, Cd, Pb, Cu, Cr, Fe, Mn, Ni, Ti, and Zn in different parts of cultivated and native plants in "gossan" area and relationship with soil content, in an area that has been used for decades by small family farmers for the crops production and raising small animals. The metals were analyzed by ICP-OES in plant and soil extracts obtained after acid digestion (USEPA SW-846 3050B). As, Cd, and Ni were not found in the evaluated plants. Pb, Fe and Ti concentrated in the roots of several plants, with emphasis on buffel grass (Pb and Fe) and corn and white pinion (both Fe and Ti). Zn and Mn were distributed in all parts of plants evaluated. Cu levels found were quite below of phytotoxic levels. Significant positive correlation between lead in root and soil and negative between lead in stem, leaf, and soil were observed, indicating a plant protection mechanism concentrating lead in the root without translocating it to the aerial part. Similar behavior has occurred in relation to Cu, concentrating it in the root and fruit. Fortunately for the farmers and consumers, the highest concentration of heavy metals was observed in the roots of both cultivated and native plants. [ABSTRACT FROM AUTHOR]

The continental shelf adjacent to the municipality of Salvador (CSS), state of Bahia, Brazil, is one of the narrowest in the world (8 km) although it is located in a passive margin. This shelf is also shallow, with low accommodation space and sediment input. During the Quaternary, the area was exposed most of the time to subaerial conditions. This long period of erosion, controlled by the structural and lithological framework of the Cretaceous Northern Camamu Sedimentary Basin, was highly influential on shelf physiography. The paleo relief that was generated, in turn, controlled sedimentation during the sea-level rise since the Last Glacial Maximum (LGM). The present study used high-resolution shallow seismic surveys to investigate the influence of the structural framework of the Northern Camamu Sedimentary Basin on the erosion of CSS during lowstands and on sediment accumulation during highstands. Five seismic units were identified, representing the Crystalline Basement, the Northern Camamu Sedimentary Basin, and the Quaternary Sediments. Bathymetric highs and lows on the shelf are associated, respectively, with antiforms and synforms present in the syn-rift strata of the sedimentary basin. Normal and transfer faults related to the installation of the sedimentary basin controlled the incision of valleys during periods of subaerial exposure. This structural framework still presents a morphological expression on the shelf due to an immensely reduced sediment input, which precluded the burial of these structures. [ABSTRACT FROM AUTHOR]

Community structure of many systems changes across space in many different ways (e.g., gradual, random or clumpiness). Accessing patterns of species spatial variation in ecosystems characterized by strong environmental gradients, such as estuaries, is essential to provide information on how species respond to them and for identification of potential underlying mechanisms. We investigated how environmental filters (i.e., strong environmental gradients that can include or exclude species in local communities), spatial predictors (i.e., geographical distance between communities) and temporal variations (e.g., different sampling periods) influence benthic macroinfaunal metacommunity structure along salinity gradients in tropical estuaries. We expected environmental filters to explain the highest proportion of total variation due to strong salinity and sediment gradients, and the main structure indicating species displaying individualistic response that yield a continuum of gradually changing composition (i.e., Gleasonian structure). First we identified benthic community structures in three estuaries at Todos os Santos Bay in Bahia, Brazil. Then we used variation partitioning to quantify the influences of environmental, spatial and temporal predictors on the structures identified. More frequently, the benthic metacommunity fitted a quasi-nested pattern with total variation explained by the shared influence of environmental and spatial predictors, probably because of ecological gradients (i.e., salinity decreases from sea to river). Estuarine benthic assemblages were quasi-nested likely for two reasons: first, nested subsets are common in communities subjected to disturbances such as one of our estuarine systems; second, because most of the estuarine species were of marine origin, and consequently sites closer to the sea would be richer while those more distant from the sea would be poorer subsets. [ABSTRACT FROM AUTHOR]

Ecological connectivity depends on key elements within the landscape, which can support ecological fluxes, species richness and long-term viability of a biological community. Landscape planning requires clear aims and quantitative approaches to identify which key elements can reinforce the spatial coherence of protected areas design. We aim to explore the probability of the ecological connectivity of forest remnants and amphibian species distributions for current and future climate scenarios across the Central Corridor of the Brazilian Atlantic Forest. Integrating amphibian conservation, climate change and ecological corridors, we design a landscape ranking based on graph and circuit theories. To identify the sensitivity of connected areas to climate-dependent changes, we use the Model for Interdisciplinary Research on Climate by means of simulations for 2080–2100, representing a moderated emission scenario within an optimistic context. Our findings indicate that more than 70% of forest connectivity loss by climate change may drastically reduce amphibian dispersal in this region. We show that high amphibian turnover rates tend to be greater in the north-eastern edges of the corridor across ensembles of forecasts. Our spatial analysis reveals a general pattern of low-conductance areas in landscape surface, yet with some well-connected patches suggesting potential ecological corridors. Atlantic Forest reserves are expected to be less effective in a near future. For improved conservation outcomes, we recommend some landscape paths with low resistance values across space and time. We highlight the importance of maintaining forest remnants in the southern Bahia region by drafting a blueprint for functional biodiversity corridors. [ABSTRACT FROM AUTHOR]

Tropical wet-dry climate seasonality is widely recognized as an important condition to phytoplankton communities' structure in freshwater ecosystems; however, there are few studies in that field in northeast Brazilian rivers. This study aimed to evaluate the influence of water quality seasonal variability over the phytoplankton dynamics and identify seasonality in eutrophication phenomena in a poorly studied neotropical river. Water quality variables and phytoplankton were examined within the Jequitinhonha River lower course, Bahia (Brazil) from 2010 to 2012. A 3-year time series was analyzed for both rainy and dry seasons. Descriptive, inferential, and multivariate analyses (CCA) were performed. Results indicated that chemical oxygen demand, dissolved aluminum, and turbidity were the main factors which influenced phytoplankton community structure and composition. Dry season was favorable for diatoms and Chlorophyceae (chlorophylls) while rainy season was favorable for cyanobacteria. Still, it was revealed that, in dry season, lower values for turbidity, chemical oxygen demand, dissolved aluminum, and dissolved iron were related with an eutrophication phenomenon. [ABSTRACT FROM AUTHOR]

The pollutants' emissions from on-road transport are critical pressure on the climate change scenario, and most developing countries rely on mostly diesel transportation. The current study aimed to estimate the environmental impact of the distance from the agricultural production area of fresh food (papaya, potato, and tomato) to a fresh food distribution center located in Campinas, Sao Paulo, Brazil. The way the products were carried was assessed for calculating the total transported volume. The total amount carried was measured, considering the number of trips multiplied by the total distance traveled within a year of supply. An online calculator was used to evaluate the amount of CO2 emission, and to allow the estimative of the amount of CO2-eq, that is the Global Warming Impact (GWP) in 100 years. The highest CO2 emission was identified in the potato transported from Paraná State to the distribution center, with a CO2-eq emission of 3237 t/year (64% of contribution), followed by the papaya from Bahia State (2723 t/year, 42% of contribution), and the tomato from Sao Paulo State (625 t/year, 71% of contribution). However, when computing the GWP, the highest value was found in the transport of potato from the Minas Gerais State (8 × 10−2 in 100 years) followed by the papaya from Rio Grande do Norte State (5 × 10−2 in 100 years) and the papaya from Bahia (3 × 10−2 in 100 years). The higher the amount of product transported by a trip, the smaller the environmental impact in the long run. A proper strategy to reduce the environmental impact would be to have large freight volume when transporting food from vast distances within continental countries. [ABSTRACT FROM AUTHOR]

Aims: In the semi-arid region of Bahia State, Brazil, sisal ( Agave sisalana Perrine ex Engelm) has been cultivated for fibre production for several decades without the use of chemical fertilizers. The contribution of biological nitrogen fixation (BNF) to this crop and the occurrence of diazotrophic rhizosphere, epiphytic or endophytic bacteria have not been investigated. The aims of this work were to study the occurrence and diversity of diazotrophic bacteria in rhizosphere soil, root and leaf tissues of sisal plants from this region, as well as to test their potential for plant growth promotion. Methods: Burk's nitrogen free semi-solid medium was used for isolation and the MPN method was used for quantification of diazotrophic bacteria. BOX-A1R PCR and 16S rRNA sequence analyses were performed to study the diversity of bacterial isolates harboring the nifH-gene. Six isolates were selected for growth promotion of cucumber plants. Results: A high diversity of BNF bacterial isolates was observed in sisal plants and rhizosphere soil. Bacterial populations were higher in roots, followed by soil and sisal leaves. Burkholderia, Leifsonia and Paenibacillus were the predominant genera. All isolates tested were able to promote cucumber growth. Conclusions: This study showed that sisal-associated diazotrophic bacteria are diverse and may be further exploited to promote plant growth. [ABSTRACT FROM AUTHOR]

Enrichment planting is a technique that is gaining recognition for its potential to restore native forests. Due to the steep economic trade-offs involved and dearth of silvicultural and ecological knowledge about native flora, however, it remains unclear whether it has promise for widespread application. Focusing on growth performance, this study explores the restoration potential of twenty-one native tree species 3 years after planting in the understory of a rubber plantation in southern Bahia, Brazil. We tested the effects of slope, aspect, successional guild and basal area of the overstory rubber trees on the enriched species' height, root collar diameter, and diameter at breast height. Height was the growth parameter that most differentiated species, with Parkia pendula, Sloanea monosperma, and Tachigali densiflora being three of the most successful species. Pioneer species grew faster than the non-pioneer species. Overstory basal area was the most important variable influencing the performance of the planted tree seedlings, while aspect and slope were less important. For every additional unit of basal area per hectare of rubber, there was an incremental decrease in the growth rates of the enrichment species. This suggests that the tree species are likely limited by available light, and that there are distinct trade-offs between overstory rubber density and understory tree species growth that are important to consider when accelerating forest recovery by using enrichment planting techniques. [ABSTRACT FROM AUTHOR]

Due to the attack of cacao ( Theobroma cacao L.) plants by the fungus Moniliophthora perniciosa which caused witches' broom disease in the state of Bahia, Brazil, resistant clonal material with elevated productivity and superior physical characteristics has been selected for use in the genetic improvement program and by the cocoa producers themselves. The present study aimed to characterize the cocoa butter and chocolates produced from nine cacao varieties and also from the Amelonado cacao produced in the same region (denominated as Common), with a view to quality improvement. The cocoa butter was characterized for its solid fat content and triacylglycerol composition, and the chocolates for their moisture and protein contents, maximum particle diameter, pH value, acidity, rheological properties and instrumental texture, as well as a sensory test for acceptability with 50 consumers. A relationship was found between the triacylglycerol composition and solid fat curves of the cocoa butters and the instrumental texture of the chocolates, the highest values for the latter parameter being observed for the varieties with greater amounts of symmetrical triacylglycerols and greater solid fat contents at the temperatures evaluated. From a sensory point of view, it was shown that overall acceptance and buying intention were mainly determined by the attributes of 'astringency,' 'bitterness,' 'acidity' and 'chocolate flavor.' It was also shown that chocolates produced from varieties descendent from the Trinitario group were differentiated from those descendent from the Forastero group, showing the preference of consumers for these materials and the possibility of a gain in quality in the genetic improvement of cacao by including varieties descended from the Trinitario and Criollo groups in the crossing programs, associating disease resistance with product quality. [ABSTRACT FROM AUTHOR]

Coral reefs around the world are facing serious threats. These fragile ecosystems are in need for conservation. The coastal state of Bahia hosts the most extensive and richest area of coral reefs in the South Atlantic Ocean. Assessment, planning and management of coral reef ecosystems are particularly challenging tasks. This work shows how the creation of a GIS improves the process of management, monitoring and conservation of the Bahian reef environments The initial data input started by the vectorization of 1) bathymetric data from the Bureau of Hydrography and Navigation (DHN), 2) shoreline and mangrove areas from Landsat 7 ETM + images, 3) near surface reefs from Quickbird images, and 4) coastal and marine protected areas of federal, state and local administrations. Geological, physical, biological and social information was then included in order to create a suitable marine GIS for conservation aims. The data includes information on sediment granulometry and transport patterns, rocky substrate outcrops, sea surface temperature, wave direction, rain precipitation, major contributing river discharge, artisanal fishery, benthic cover and bleaching data. ReefBahia GIS has provided essential information for a better understanding of coral reefs of the state of Bahia geological and ecological characteristics such as mapping, representation, connectivity and biodiversity of coral reefs, geological facies, Quaternary sedimentation, numeric modeling of wave refraction and monitoring of bleaching events. [ABSTRACT FROM AUTHOR]

Studies have investigated the exposure levels of carbonyl compounds (CC) in the indoor and outdoor air of homes, vehicles, workplaces, urban and industrial areas, and rural sites. However, an investigation of these emissions and occupational exposure to CC in charcoal production facilities has not been previously conducted. The objective of this study was to measure the atmospheric concentrations of several CC to assess the exposure of workers of two charcoal plants located north of Salvador, Bahia, Brazil. Stationary and personal samples were collected using Sep-Pak® C18 cartridges that were coated with a 0.2 % acidic solution of 2,4-dinitrophenylhydrazine. The quantification of the resulting 2,4-dinitrophenylhydrazone derivatives was conducted using a high-performance liquid chromatography system with UV detection. In the personal samples, the concentrations of formaldehyde, acetaldehyde, propanone, furfural, and C4 isomers ( n-butanal-isobutanal-butanone) ranged from 12 to 139, 38 to 165, 136 to 483, 39 to 114, and 63 to 132 μg m, respectively. In the stationary samples, the concentrations of these CC ranged from 20 to 160, 111 to 284, 328 to 644, 70 to 163, and 100 to 176 μg m, respectively. When compared to the occupational exposure limits for 8 h, the concentrations of formaldehyde were often greater than the levels recommended by the American National Institute for Occupational Safety and Health, which indicates a health risk for charcoal workers. These results are the first reported concerning the occupational exposure to CC in charcoal plants. [ABSTRACT FROM AUTHOR]

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Euglossa cyanochlora Moure, (Hymenoptera: Apidae: Euglossina) is known from only two specimens and is considered as one of the rarest bees. An intensive search for this species in its expected area of occurrence in eastern Brazil was carried out during three consecutive summers and involved over 1,000 h of active sampling in 50 sites distributed among 20 forest remnants. Almost 15,000 orchid bee males were attracted to scent baits and collected, but only 24 of them belonged to E. cyanochlora. Some degree of mitochondrial gene (COI, cytB, and 16S) variation was observed in this species. Although no intra-specific variation was identified at the 16S locus, three and six haplotypes were characterized at the COI and cytB genes, respectively. Combined data from field work and molecular analysis suggest that the species southernmost distribution limit is close to its type locality, near Parque Nacional do Monte Pascoal, in southern Bahia. The conservation status of E. cyanochlora is discussed and measures for its protection are here proposed. [ABSTRACT FROM AUTHOR]

Large amounts of plant litter deposited in cacao agroforestry systems play a key role in nutrient cycling. Organic matter, nitrogen and phosphorus cycling and microbial biomass were investigated in cacao agroforestry systems on Latosols and Cambisols in Bahia, Brazil. The objective of this study was to characterize the microbial C and N, mineralizable N and organic P in two soil orders under three types of cacao agroforestry systems and an adjacent natural forest in Bahia, Brazil and also to evaluate the relationship between P fractions, microbial biomass and mineralized N with other soil attributes. Overall, the average stocks of organic C, total N and total organic P across all systems for 0-50 cm soil depth were 89,072, 8,838 and 790 kg ha, respectively. At this soil depth the average stock of labile organic P was 55.5 kg ha. For 0-10 cm soil depth, there were large amounts of microbial biomass C (mean of 286 kg ha), microbial biomass N (mean of 168 kg ha) and mineralizable N (mean of 79 kg ha). Organic P (total and labile) was negatively related to organic C, reflecting that the dynamics of organic P in these cacao agroforestry systems are not directly associated with organic C dynamics in soils, in contrast to the dynamics of N. Furthermore, the amounts of soil microbial biomass, mineralizable N, and organic P could be relevant for cacao nutrition, considering the low amount of N and P exported in cacao seeds. [ABSTRACT FROM AUTHOR]

In southern Bahia, Brazil, cabrucas are the traditional agroforests in which cacao trees are planted under thinned-out native forests. To analyze the role of cabrucas in tree species conservation, we inventoried the non-cocoa trees in 1.0 ha plots of cabruca in 16 cocoa farms and compared our results with a similar survey undertaken in the early 1960s in the same region to analyze the long term changes. We also interviewed 160 cocoa farmers to investigate their preferences for species and the main practices used in managing shade trees. The cabrucas showed high levels of tree diversity for an agroforestry system (Shannon index ranging from 2.21 to 3.52) and also high variation in structure and composition among the different farms. Forest specialist trees accounted for most species (63.9%) in the survey and were among the species most preferred by the farmers, although we found evidence that some of these trees are gradually being replaced by other species. Our results indicate that cabrucas are poor substitutes for undisturbed forests in terms of tree species richness, but their presence in human-altered landscapes is of utmost importance to the conservation of forest tree species as they increase overall heterogeneity and may serve as ecological corridors, additional habitats, and buffer zones. [ABSTRACT FROM AUTHOR]

This study aimed to compare the sensitivity of five diagnostic methods commonly used for the detection of Toxoplasma gondii in tissues of naturally infected pigs. We purchased 20 heads of pigs in butcher shops in the city of Ilhéus, Bahia. Brain and tongue fragments were taken from each animal for the performance of PCR against T. gondii. The rest of these two tissues were processed and inoculated into three mice. These rodents were observed for 42 days and euthanized. We prepared slides with brain and lungs of each mouse for the visualization of T. gondii. From the tissues of mice, we carried out polymerase chain reaction (PCR), histopathology, and immunohistochemistry in an attempt to identify the parasite. The PCR direct from the tissue of pigs showed 10% (2/20) of positive samples, all from the brain. PCR in tissue from mice found that 55% (11/20) of pigs were positive: 55% (11/20) and 45% (9/20) for brains and tongues, respectively. Mice were inoculated with material obtained from the samples and examined by various methods for resulting Toxoplasma infection (bioassay). Cyst detection in bioassay mice identified 25% (5/20) and immunohistochemistry 30% (6/20) of the samples pigs as positive for T. gondii. Histopathology of mice tissue could not detect parasite; only suggestive pathological changes such as inflammation with foci of necrosis were seen. The results indicated PCR of mice tissue as the most sensitive among those tested. [ABSTRACT FROM AUTHOR]

groforestry systems (AFSs) have an important role in capturing above and below ground soil carbon and play a dominant role in mitigation of atmospheric CO. Attempts has been made here to identify soil organic matter fractions in the cacao-AFSs that have different susceptibility to microbial decomposition and further represent the basis of understanding soil C dynamics. The objective of this study was to characterize the organic matter density fractions and soil size fractions in soils of two types of cacao agroforestry systems and to compare with an adjacent natural forest in Bahia, Brazil. The land-use systems studied were: (1) a 30-year-old stand of natural forest with cacao (cacao cabruca), (2) a 30-year-old stand of cacao with Erythrina glauca as shade trees (cacao + erythrina), and (3) an adjacent natural forest without cacao. Soil samples were collected from 0-10 cm depth layer in reddish-yellow Oxisols. Soil samples was separated by wet sieving into five fraction-size classes (>2000 μm, 1000-2000 μm, 250-1000 μm, 53-250 μm, and <53 μm). C and N accumulated in to the light (free- and intra-aggregate density fractions) and heavy fractions of whole soil and soil size fraction were determined. Soil size fraction obtained in cacao AFS soils consisted mainly (65 %) of mega-aggregates (>2000 μm) mixed with macroaggregates (32-34%), and microaggregates (1-1.3%). Soil organic carbon (SOC) and total N content increased with increasing soil size fraction in all land-use systems. Organic C-to-total N ratio was higher in the macroaggregate than in the microaggregate. In general, in natural forest and cacao cabruca the contribution of C and N in the light and heavy fractions was similar. However, in cacao + erythrina the heavy fraction was the most common and contributed 67% of C and 63% of N. Finding of this study shows that the majority of C and N in all three systems studied are found in macroaggregates, particularly in the 250-1000 μm size aggregate class. The heavy fraction was the most common organic matter fraction in these soils. Thus, in mature cacao AFS on highly weathered soils the main mechanisms of C stabilization could be the physical protection within macroaggregate structures thereby minimizing the impact of conversion of forest to cacao AFS. [ABSTRACT FROM AUTHOR]

groforestry systems can play a major role in the sequestration of carbon (C) because of their higher input of organic material to the soil. The importance of organic carbon to the physical, chemical, and biological aspects of soil quality is well recognized. However, total organic carbon measurements might not be sensitive indicators of changes in soil quality. Adoption of procedures that can extract the more labile fraction preferentially might be a more useful approach for the characterization of soil organic carbon resulting from different soils. This study aimed to evaluate organic carbon (C) fractions distribution in different soil layers up to 50 cm depth in two soil orders under cacao ( Theobroma cacao) agroforestry systems (AFS) in Bahia, Brazil. Soil samples were collected from four depth classes (0-5, 5-10, 10-30 and 30-50 cm) under two cacao agroforestry systems (30-year-old stands of cacao with Erythrina glauca, as shade trees) in Latosol and Cambisol, in Bahia, Brazil. The determination of oxidizable carbon by a modified Walkley-Black method was done to obtain four C fractions with different labile forms of C (fraction 1: labile fraction; fraction 2: moderate labile fraction; fraction 3: low labile fraction and fraction 4: recalcitrant fraction). Overall, at two cacao AFS, the C fractions generally declined with increase in soil depth. The C fractions 1 and 2 were 50% higher on upper layers (0-5 and 5-10 cm). More than 50% of organic C was found in more labile fraction (fraction 1) in all depths for both soils. High value of C fraction 1 (more labile C)-to-total organic C ratio was obtained (around 54-59%, on Latosol and Cambisol, respectively), indicating large input of organic matter in these soils. [ABSTRACT FROM AUTHOR]

Purpose: The present study presents data on the screening phase (tier 1) of a site-specific ecological risk assessment in a former smelter area heavily contaminated with metals (Santo Amaro, Bahia, Brazil). Joining information from three lines of evidence (LoE), chemical, ecotoxicological, and ecological, integrated risk values were calculated to rank sites within the area and identify those that may need further investigation in tier 2. Materials and methods: Eleven points were selected up to 1,000 m from the smelter. Three reference points were 3 and 9 km away from the area. Risk values for the chemical LoE were derived from calculating the toxic pressure based on total metal concentrations. Those for the ecotoxicological LoE were based on avoidance ( Folsomia candida and Eisenia andrei) and eluate tests ( Daphnia magna acute test and Microtox) whereas for the ecological LoE the bait lamina test, soil basal respiration, and vegetation cover were used to derive risk values. Results and discussion: The chemical LoE showed high risk in those points inside the area where metal loadings exceeded in much the existing soil screening values. Ecotoxicological tools showed a variable response, with tests on soil organisms inducing a higher risk (again at sites inside the smelter and with sandy soils) than tests on eluates. The three parameters composing the ecological LoE revealed a concordant response, despite the lower sensitivity of the vegetation cover. A high risk on this LoE was also observed on those sampling points where a high chemical risk was calculated. Conclusions: Integrated risk was low outside the smelter area. Inside, a high spatial heterogeneity of risk levels was observed, related to the non homogeneous deposition of smelting residues. Very high risk levels, associated with sandy soils and residue deposits, suggest the need to proceed with remediation actions. However, the uncertainties associated with the contradictory information given by certain LoEs for certain sampling points show the need to confirm potential risks in a tier 2 analysis. [ABSTRACT FROM AUTHOR]

Abstract   Neospora caninum, Hammondia sp., and Toxoplasma gondii are parasites with morphological and genetic similarities. N. caninum and T. gondii are important abortive agents of cattle and sheep, respectively, and may infect numerous animal species. Hammondia sp. is not known to induce disease in animals, but may cause confusion in the identification of closely related coccidia. The aim of this study was to investigate infection rates caused by N. caninum, Hammondia sp., and T. gondii in beef cattle using a nested PCR for Toxoplasmatinae rDNA, followed by sequencing of the PCR products. Antibodies to N. caninum and T. gondii were also investigated in the tested animals. Brains and hearts were obtained from 100 beef cattle in a slaughterhouse in Bahia. Seven samples from brain tested positive for Toxoplasmatinae DNA. No positive reactions were found in heart tissues. After sequencing of the PCR products from all positive tissues, five sequences matched with N. caninum and two matched with T. gondii. Antibodies to N. caninum and T. gondii were found in 20% and 26% of the animals, respectively. The confirmation of N. caninum and the absence of Hammondia heydorni in the tested animals is suggestive that cattle are not efficient intermediate hosts of H. heydorni; however further studies need to be performed using a greater variety of tissues and a higher sample size. The detection of T. gondii DNA in bovine tissues reinforces the potential risk of transmission of this parasite to humans and other animals through the consumption of bovine meat. [ABSTRACT FROM AUTHOR]

Dimorphandra jorgei MF Silva (Caesalpinaceae) and Swartzia macrostachya Benth. var. riedelii Cowan (Fabaceae) are tree species from the southern Bahian Atlantic Forest, identified for the restoration of degraded areas. The objective of this research is to study their seed germination and seedling growth to develop simple methods for seedling production in small scale nurseries. Because the species have distinct dormancy and germination characteristics, the seeds were submitted to different treatments. D. jorgei seeds were immersed in hot water, scarified and stored for 12 weeks in the laboratory environment (25°C). S. macrostachya seeds were submitted to different combinations of drying and storage in the laboratory environment or refrigerator (4°C). Seedlings were submitted to two light treatments for 3 months: partial shade (52% of full sun) and full shade (12% of full sun). In D. jorgei, the highest germination occurred for scarified seeds (87%) and for seeds stored for 12 weeks and then scarified (69%). In S. macrostachya the undried control seeds had the highest germination, followed by that of the refrigeration storage treatment, without predrying (99% and 97%, respectively). The average values for the growth parameters were greater in full shade for D. jorgei, while S. macrostachya seedlings showed greater growth rates in partial shade. Two months growth is recommended before D. jorgei seedlings are of the sufficient size and leaf number for field planting. On the other hand, a period of 4 months is recommended for S. macrostachya, due to its relatively slow growth. [ABSTRACT FROM AUTHOR]