Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Os estudos hidrossedimentológicos abordam as contribuições da agricultura,do meio urbano e das demais ocupações da terra, entretanto as estradasrurais inseridas nas bacias hidrográficas dificilmente são observadas comocontribuição específica ou potencialmente contributiva. Desse modo, osobjetivos deste estudo foram simular diferentes cenários e características paraas estradas rurais e, assim, avaliar o fluxo de águas e sedimentos em bacias comagricultura familiar localizadas no sul do Brasil. Para isso, utilizou‑se o modelohidrológico soil and water assessment tool (SWAT). Na etapa de calibraçãoda vazão para a bacia do Ribeirão Concórdia, obtiveram‑se o coeficientede Nash-Sutcliffe (COE) de 0,76 e, para a validação, o coeficiente de 0,78.Na bacia do Rio Camboriú, a calibração alcançou COE de 0,67. Na calibraçãoe validação sedimentológica na bacia do Ribeirão Concórdia, obteve-se COEde 0,82 e de 0,68, respectivamente. Na bacia do Rio Camboriú, a calibraçãosedimentológica atingiu coeficiente de 0,59. Quando comparada com ocenário sem as estradas, a inserção de estradas rurais como uso específicoda terra (cenário calibrado) resultou em aumento de 6,3% na vazão e de8,8% nos sedimentos transportados na bacia do Ribeirão Concórdia. Na baciado Rio Camboriú, houve diferenças inferiores a 0,4%. Portanto, mesmoapresentando uma pequena área dentro da bacia, as estradas rurais podeminterferir na vazão e no volume de sedimentos transportados.

Magnetite consists of a mineral with excellent magnetic and mechanical properties, being present in iron extraction tailings, which are available worldwide in millions of tons deposited in landfills. In relation to variety of the material characteristics, according to specificities of the extraction deposit and processing and reprocessing operations, for its technological application it´s fundamental to perform waste characterization. The most promising forms of magnetite tailings reuse refer to its application in asphalt mixtures and concrete. In this context, this work approaches the main techniques for the technological characterization of magnetite tailings and their contributions, as well as results of studies for incorporation of mineral byproduct into asphalt and concrete. It has been identified that techniques used analyze the tailings and/or composite asphalt material and concrete considering the physical, chemical, mineralogical and thermodynamic properties. The magnetite tail as a partial and integral substituent of the filler material has been found to improve the corrosion resistance and cracking of the asphalt mixtures. In addition, the use of magnetite powder, extracted from waste, improves stiffness and elastic response, as well as promotes microcracks cure of bituminous mixture. Incorporation of powdered mineral waste in the concrete resulted in improvements in the workability and strength of the material. The information in this review provides an overview of the characterization techniques and recycling prospects of magnetite tailings in civil construction.

REDD+ has been addressed under the United Nations Framework Conventionon Climate Change as a central instrument to mitigate climate change. Brazil isa key country in this issue, as it has international commitments to reducedeforestation, REDD+ initiatives underway and land issues as a critical factor ofdeforestation. This research aimed to analyze REDD+ initiatives, according tothe land regime, with emphasis on factors of accountability (right holder) andpermanence of forest resources. Fifty‑six REDD+ initiatives were consideredand analyzed through 17 variables. For the first factor, initiatives weremapped on private, public and mixed properties that presented differencesbetween project proponent, but with similar geographical characteristics.Regarding the permanence, the initiatives, regardless of the type of property,are in areas of land conflicts and addressed actions for forest monitoring.However, variations between deforestation agents and the presence ofresidents who do not own the property were identified. These results pointto different gaps in land issues, which demand a differentiated approach,according to the type of property, in order to guarantee REDD+ results.

Este estudo teve como objetivo aplicar uma metodologia que avalie a qualidadeda água bruta e sua relação com usos e ocupações do solo por meio de análiseestatística multivariada e do Sistema de Informações Geográficas. Potencial dehidrogênio, temperatura da água, oxigênio dissolvido, demanda bioquímicade oxigênio, demanda química de oxigênio, nitrogênio total, fósforo total eE. coli foram monitorados de agosto de 2012 a março de 2013. A ferramentade geoprocessamento permitiu a delimitação das áreas de contribuiçãode cada local de amostragem, bem como a identificação individual do usodo solo de cada área. A Análise de Componentes Principais (ACP) resultouem: esgoto doméstico, esgoto doméstico/agricultura e descarga industrial.Correlações significativas foram identificadas entre as variáveis ‘área urbana’e ‘potencial hidrogeniônico’ (ρ = 0,446; p = 0,049), oxigênio dissolvido(ρ = -0,625; p = 0,003), nitrogênio total (ρ = 0,649; p = 0,002) e E. coli (ρ = 0,932;p < 0,001). A metodologia estabelecida possibilitou identificar a contribuiçãodos fatores de uso do solo em relação à qualidade da água.

Among the environmental factors, water deficit affects several morphologicaland physiological processes in plants, which may affect crops’ growth anddevelopment, reflecting on the yield. Thus, the aim of this research wasto evaluate the physiological responses of peanut genotypes submitted towater deficit. The experimental design was a completely randomized blockwith treatments in a 12x2 factorial arrangement, with twelve genotypesand two hydric conditions, with 5 replications. To evaluate the effect ofstress, at 25 days after emergence (DAE) peanut plants were kept underwater deficiency for four days, while the controls were kept at 70% offield capacity. At 29 DAE, photosynthesis, transpiration rate, relativewater and epicuticular wax content were evaluated. The photosyntheticrate was lower for all water deficit genotypes, except for the 870 strain,which showed higher drought tolerance. Water deficit did not affect thetranspiration rate of Runner IAC 886, IAC OL3, IAC OL4 cultivars and 573,599, 870 breeding lines. Among the genotypes, there is variation in theamount of the epicuticular waxes under water-deficit conditions. In relation to anatomo-physiological aspects from the genotypes, it was concluded that lines 573 and 870 are highly tolerant to water deficiency; cultivars IAC OL3, IAC OL4, Runner IAC 886, and 599 and 967 lines are moderately tolerant, and IAC 503, IAC 505 and IAC Tatu-ST, and lines 322 and 506 are more sensitive to water stress during phase of flowering.

Mangroves are ecosystems with significant environmental and socioeconomic relevance and knowledge of the ecological relationship between this ecosystem and the atmosphere is of fundamental importance for its preservation and sustainable use of natural resources. In this sense, this study aims to analyze the precipitating meteorological systems and their seasonal rainfall variation on the Amazon coast and their influenceon the variability of litterfall production in the mangrove forest. 3 plots were delimited with 12 collectors of 1 m2 litterfall in the experimental site of Cuiarana. The collections were performed monthly and were classified into leaf, woody, reproductive material and miscellaneous. Rainfall data from the Micrometeorological Tower and CPC MORPHing technique (CMORPH) were used. Two-way and one-way ANOVA (p < 0,05) and linearregression analysis (p < 0,05) were used. The results indicate that the temporal variation of precipitation is modulated by different meteorological systems. In the production of litterfall there was significant difference between the monthly production values and between the fractions of litterfall. The total annual production of litterfall was 9.4 ± 0,06 Mg ha-1 year-1, where 67% was composed by the leaf fraction. The analyses of thefraction Total leaf and leaf of the species L. racemosa showed significant correlation with precipitation (r2 = 0,36 and r2 = 0,72; p < 0,05), respectively. In view of the results, it is concluded that the production of mangrove litterfall has a direct relationship with the precipitating systems.

Water is indispensable for human life, but the degradation of this resource has been occurring uncontrollably. Thus, the formulation of environmental public policies that provide a planning of the watersheds’ land use and cover at regional scales is indispensable. Only through regional governance will it be possible to integrate public policies that prioritize the economic development of a society and environmental protection. The present study evaluated the shortcomings associated with the Hydrographic Basins Plans and the Master Plans of the municipalities belonging to the Ribeirão do Feijão River Basin, based on a survey of land use and cover of 1998, 2008 and 2018. The expansion of the anthropic areas has been verified, causing a deterioration of natural areas and, consequently, ecosystem services. In this way, the creation of strategic environmental planning at the regional level will assist in the sustainable development of municipalities within the river basin.

Ozone (O3) is one of the main pollutants that contribute to air quality deterioration in urban areas. It is a secondary pollutant, produced in the atmosphere by photochemical reactions, in a way that its formation depends both on meteorological and chemical factors. This work aims to analyze the interannual variability of O3 concentrations at the Sao Paulo metropolitan region between 2005 and 2015, isolating the contribution of chemical factors using the Kolmogorov-Zurbenko filter. Results indicate that the variability of meteorological conditions explained from 39 to 52% of O3 concentration variance during the study period. O3 concentration peaks in the long-term time series component were mainly associated with chemical factors, associated with changes in the emission pattern of precursors. Years with high O3 concentrations occurred simultaneously with increases on the gasoline usage relative to ethanol.

Estudar a variabilidade dos parâmetros hidroclimáticos locais em baciashidrográficas é importante para melhorar o gerenciamento dos recursos hídricos.Para tal, foram utilizados o modelo estatístico baseado na metodologia Box-Jenkins, adotado por muitas empresas na análise de séries temporais, inclusivetodo o setor elétrico brasileiro, e a tecnologia de redes neurais, que se apresentacomo poderosa ferramenta para previsões. Na comparação entre as duas técnicas,foram utilizadas observações de médias mensais de duas estações meteorológicasda Bacia Araguaia-Tocantins, Brasil, uma de vazões mensais (m3/s) e outra deprecipitações pluviométricas mensais (mm), da Agência Nacional de Águas (ANA),com registros contínuos nos períodos de 1969 a 2017 e 1974 a 2017. As previsõesforam testadas para 12 e 24 meses. Uma comparação entre os dois métodos,usando o teste de hipótese a partir de intervalos de confiança de 95%, mostrouque não houve diferenças estatisticamente significativas nas previsões individuaistanto de precipitações pluviométricas como de vazões. Entretanto, o uso do rootmean square error (RMSE) mostrou que o método de Box-Jenkins apresentamelhores resultados. A maior dificuldade nesse método é na construção domodelo, sobretudo em séries com alta variabilidade. O método de redes neurais,em geral, consome mais tempo computacional em relação ao Box-Jenkins.

O conhecimento sobre a qualidade da água por meio da determinaçãode seus descritores é fundamental para o estabelecimento de políticas degestão dos recursos hídricos. Neste trabalho, sugere-se um método simplese prático para determinar valores associados aos descritores de qualidadeda água. Foram utilizados resultados acumulados ao longo de dez anos demonitoramento da qualidade da água superficial em microbacias do estadode Santa Catarina. Considerando as cinco classes de uso já estabelecidas nalegislação federal (Resolução do Conselho Nacional do Meio Ambiente –CONAMA nº 357/2005), foram determinados os limites para cada classetendo por base a distribuição dos valores dos parâmetros em estudo.A mediana foi utilizada para estabelecer os valores de referência de qualidadee o percentil 60 como limite máximo para considerar o valor do descritorcomo aceitável. O método apresentado é de fácil aplicação e os valorescalculados, comparados à legislação vigente, são mais restritivos, sugerindoboa qualidade da água.