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Este trabalho propõe uma metodologia para obtenção de dados de irradiação solar incidente na superfície da região Norte do Brasil utilizando o modelo numérico regional de mesoescala BRAMS em conjunto com uma técnica de remoção de viés. Este tipo de solução se faz necessário em virtude dos erros sistemáticos inerentes às simulações, ocasionados, por exemplo, pela dificuldade na representação da variabilidade da cobertura de nuvens. A técnica estatística de remoção de viés foi desenvolvida utilizando dados observacionais de irradiação solar de estações meteorológicas do Instituto Nacional de Meteorologia (INMET) operando na área de estudo ao longo do ano de 2009. Verificou-se que o modelo BRAMS é capaz de reproduzir satisfatoriamente os ciclos mensais e diários da irradiação solar, mas existe uma clara tendência de superestimar os valores em relação aos dados observados. A validação com dados de superfície mostrou que a técnica estatística de remoção do viés conseguiu reduzir significativamente estes erros, aproximando os valores simulados daqueles observados em superfície.

The aim of this paper is using TerraME framework to develop a model that contributes in understanding the spatiotemporal behaviour of dengue transmission and the strength of control strategies. During the implementation of our model, it was necessary to adopt rules and input parameters, which represent potential determinants factors for dynamic transmission of dengue fever. The use of these rules allows simulating scenarios of epidemics in the absence and in the presence of dengue transmission control measures.

Próximo de completar uma década de atividades, o projeto Apoio técnico às atividades de extração de matéria-prima executadas pela indústria oleira da região de Rio Claro realizou, recentemente, o estudo da viabilidade do uso da nucleação como auxílio na elaboração do projeto de recuperação de uma área de preservação permanente de nascente. O resultado obtido durante esta etapa do projeto é o objetivo deste artigo, para tal será apresentada a proposta de recuperação desta área degradada que considerou etapas de caracterização da área, de monitoramento da regeneração natural, de implantação da técnica de transposição de solo e serrapilheira e de monitoramento desta técnica. Durante a caracterização, foram analisados os pré-requisitos à implantação das técnicas de nucleação. Depois de confirmada a viabilidade da implantação das técnicas de nucleação, foi escolhida a técnica de transposição de solo e serrapilheira para ser implantada e monitorada. O monitoramento ocorreu por cinco meses, após este período, foi possível observar a regeneração natural ocorrendo na área de preservação da nascente em estudo, além de indicativos de intensa atividade biológica na parcela transplantada.

Soil erosion is a serious environmental problem that has adversely affected the worlds food production through the reduction of land productivity and water availability. The present study estimated annual soil loss rate and its spatial distribution in the most important Brazils agricultural region, the Brazilian Cerrado, using Revised Soil Loss Equation (RUSLE) model into Geographic Information System (GIS) framework. For this purpose, the soil erosion annual rate was determined in function of RUSLE model factors: rainfall erosivity (R), soil erodibility (K), topography (LS), crop management (C) and supporting conservation practice (P). All factors were obtained from literature. They were processed and integrated into a GIS, resulting in a map of annual soil loss rate. The methodology applied showed acceptable precision and it was possible to identify the most susceptible areas to water erosion. The average estimated rate of soil loss for the entire Cerrado was 12.8 t∙ha−1 ∙yr−1 . Large part of the Cerrado is under low soil loss zone corresponding to 79.91% of total surface area, while 15.70%, 3.74%, and 0.66% are under moderate, high, and very high, respectively. The average estimated rate of soil loss in areas used for silviculture was 52.1 t∙ha−1 ∙yr−1 . In semi-perennial, perennial, and annual crops cultivation were 29.3, 23.9, and 9.8 t∙ha−1 ∙yr−1 , respectively, while in the pasture was 13.3 t∙ha−1 ∙yr−1 . Except for annual crops, all farm and silviculture areas showed average soil loss ranging from moderate to high rate. These results suggest that the implementation of more effective management techniques and conservation practices are necessary for the Cerrado to maintain and to improve land productivity by ensuring national and international food demands.

The present study aimed to evaluate the relationship between the physical properties of the soil and relief in areas that are susceptible to landslides in the sub-basin of the Córrego do Yung, a creek in the urban district Três Moinhos of Juiz de Fora, Minas Gerais. Depth measurements of the solum were made at the soil sampling points, and the subsurface material was collected and analyzed for the two factors of particle size and type of horizon. In the laboratory, we determined the hydraulic conductivity, bulk and particle density, and total porosity, macroporosity and microporosity. The values of the physical properties throughout the sub-basin were predicted and mapped. Thematic maps were generated and showed a relation to each other: the clay was related to a higher hydraulic conductivity, higher porosity and lower soil density. In the steeper areas, the greater silt contents were mapped in the deeper layers and indicated the thin thickness of horizon B in these areas. A close relation of the curvature with the soil thickness was detected and was greater in the flat areas with less slope. The geostatistical analysis showed that the range of values for the properties of macroporosity, microporosity and silt was the lowest in the deeper layers, indicating low structural continuity in potentially erodible areas.

Nos últimos anos os desastres naturais tais como os deslizamentos de terra em áreas urbanas e em rodovias têm se intensificado e provocado mortes e grandes prejuízos materiais no Brasil, neste contexto, o objetivo do trabalho foi analisar a relação entre a ocorrência de deslizamentos em Juiz de Fora e a pluviometria diária do município, bem como a partir da base de dados da Prefeitura/Defesa Civil, analisar a relação dos atributos do terreno do município com a legislação de uso e ocupação do solo, a fim de discutir a restrição de uso quanto à declividade. As variáveis de terreno empregadas neste estudo foram obtidas pelo modelo digital de elevação (MDE), tendo como base uma planta topográfica plani-altimétrica. Foram utilizados os pontos e polígonos de áreas de risco mapeados pela Defesa Civil. Analisou-se as áreas de risco em relação aos atributos do relevo, discutidos com base na lei de uso e ocupação do solo, que define que terrenos com declividade acima de 30% tem uso restrito. Os dados de pluviosidade foram correlacionados com os dias de ocorrência de deslizamentos. Os resultados apontaram a existência de 222 pontos como áreas de risco. Da sobreposição desses pontos com a declividade, obteve-se a relação entre áreas de riscos e relevo. De acordo com a lei municipal, 124 pontos estariam em áreas iguais ou acima de 30% de declividade, totalizando 56% das áreas de risco da região urbana. Apesar de vários bairros apresentarem declividades acima de 30%, as áreas de risco estão relacionadas às ocupações de baixo padrão social. Verificou-se 74% de probabilidade de deslizamento a partir de dados acumulados de chuva de 10 dias, para a precipitação igual ou acima de 150 mm, e 67% de probabilidade de deslizamentos em 15 dias de observações, para chuva igual ou acima de 200 mm. As equações obtidas nas funções lineares podem ser utilizadas pela defesa civil para enviar alerta de deslizamentos. ABSTRACT: In recent years, natural disasters such as landslides in urban areas and on highways have intensified and caused deaths and great material damages in Brazil, in this context, this study aimed to analyze the relationship between the occurrence of landslides in Juiz de Fora and daily rainfall of the municipality, as well as from the database of the City Hall / Civil Defense, analyzing the relationship of attributes of the relief of the municipality with the legislation of land use and occupation, in order to discuss the restriction of use when To declivity. it was based on the topographic planialtimetric map. It was used points and polygons risk areas mapped by the Civil Defense. It was performed spatial analysis of risk areas regarding to relief attributes, discussed based on occupation law, which define that land above 30% slope has restricted use. It was also analyzed daily rainfall correlated with the days of the landslides. The results indicate 222 points mapped as risk areas. By overlaying these points with the slope map, it was obtained the relationship between risk areas and relief. According to municipal law, 124 points were in the same or above 30% slope areas, totaling 56% of the urban region risk areas. It was observed that although several neighborhoods present many areas with slopes above 30%, the risk areas are always related to low social status occupations. It is 74% likely to slip from the cumulative rainfall data from 10 days to precipitation above 150 mm, and 67% probability of slips in 15-day observations for rain greater than 200 mm. In conclusion, the accumulated data were representative and the equations obtained in the linear functions can be used for civil defense warning slips, based on previous records.

During the austral summer of 2014 and 2015, a severe drought occurred in southeastern Brazil at the same time when flooding conditions were registered in the state of Acre in the western Amazonia of Brazil. This study aimed the identification of the atmospheric and oceanic large-scale characteristics and regional features associated with these conditions, and verification of the Center of Weather Forecasting and Climate Studies/National Institute of Space Research (CPTEC/INPE) atmospheric global circulation model ability in reproducing the observed features. The state of Acre was chosen as a pilot area of the PULSE-Brazil project – a web platform tool that contains climate, ecological and health data for Brazil. The observational data and model results were analysed for the climatological period of 1981-2010. Correlation analyses between precipitation over west Amazon and atmospheric and oceanic variables indicated the main patterns in both data sets. Extreme wet and dry Januaries over west Amazon were selected to explore the regional and large-scale associated features. The general results of climate analyses indicated an opposite relation of precipitation between western Amazon and southeastern Brazil, in January, besides the typical precipitation dipole between the south Atlantic convergence zone and southeastern South America. This configuration is related to anomalous humidity flux at low levels and associated anomalous sea level pressure over southeastern South America induced by subsidence. The role of convection anomalies over the Pacific Ocean on South America anomalies is discussed. The wet and dry cases in Acre region display opposite atmospheric anomalies over South America that are linked to wavetrains over the Pacific Ocean, likely related to the opposite conditions of Indonesia-Pacific tropical convection. Similar patterns of the dry cases were observed during January of 2014 and 2015. The model reproduced some observed atmospheric patterns related to precipitation extremes and the results are discussed in terms of regional and large-scale climate variability.

Our limited understanding of the climate controls on tropical forest seasonality is one of the biggest sources of uncertainty in modeling climate change impacts on terrestrial ecosystems. Combining leaf production, litterfall and climate observations from satellite and ground data in the Amazon forest, we show that seasonal variation in leaf production is largely triggered by climate signals, specifically, insolation increase (70.4% of the total area) and precipitation increase (29.6%). Increase of insolation drives leaf growth in the absence of water limitation. For these non-water-limited forests, the simultaneous leaf flush occurs in a sufficient proportion of the trees to be observed from space. While tropical cycles are generally defined in terms of dry or wet season, we show that for a large part of Amazonia the increase in insolation triggers the visible progress of leaf growth, just like during spring in temperate forests. The dependence of leaf growth initiation on climate seasonality may result in a higher sensitivity of these ecosystems to changes in climate than previously thought.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Litterfall is one of the most important pathways through which nutrients are recycled in the terrestrial biosphere. In tropical soils, which are generally low in essential nutrients such as phosphorus and cations, the flux of nutrients through litterfall is particularly important to sustaining CO2-uptake capacity; however, questions remain over the role of altitude in altering litter nutrient cycling rates among tropical forest ecosystems. Here we examine litterfall, carbon (C), nitrogen (N) and phosphorus (P) fluxes through litterfall over an altitudinal gradient in the coastal Atlantic Forest located on the northern coast of the State of Sao Paulo, Brazil. Litterfall was collected twice a month for 1 y (April 2007March 2008) using 30 litter traps placed in four different forest types arrayed by altitude coastal forest (sea level), lowland forest (50200 m asl), submontane forest (300500 m asl) and montane forest (1000 m asl). Litterfall mass-fluxes decreased with increasing altitude, from 9 Mg ha−1 in lowland forests to 7 Mg ha−1 in higher-altitude ecosystems. Contribution of reproductive organs to litterfall was significantly greater in lower than in higher altitudes. Litterfall N and P fluxes were higher in the lowland forest vs. other forest types, pointing to strong altitudinal controls over nutrient cycling. Furthermore, nitrogen-use efficiency (NUE) was lower and litter δ15N was higher in the lowland site providing additional evidence for lack of N constraints to productivity in lowland of the south-eastern Atlantic Forest.

The onset and demise of the rainy season in Amazonia are assessed in this study using meteorological data from the GoAmazon experiment, with a focus on the 2014 2015 rainy season. In addition, global reanalyses are also used to identify changes in circulation leading to the establishment of the rainy season in the region. Our results show that the onset occurred in January 2015, 23 pentads later than normal, and the rainy season during the austral summer of 2015 contained several periods with consecutive dry days in both Manacapuru and Manaus, which are not common for the wet season, and resulted in below-normal precipitation. The onset of the rainy season has been strongly associated with changes in large-scale weather conditions in the region due to the effect of the MaddenJulian Oscillation (MJO). Regional thermodynamic indices and the height of the boundary layer did not present a significant difference between the onset and demise of the wet season of 2015. This suggests that local changes, such as those in the regional thermodynamic characteristics, may not have influenced its onset. Thus, variability of the large-scale circulation was responsible for regional convection and rainfall changes in Amazonia during the austral summer of 2014 2015.

The Brazilian Amazon is being affected by the new worldwide geopolitical transformation that is tending towards an integrated global economy. In the region environmental considerations have not been adequately incorporated into long-term land use planning and this failure has partly been due to the complexities of the country’s existing inter-sectorial institutional arrangements. In this paper, we briefly explore two distinct economic development phases that have been reshaping Amazonian landscapes since the 1990s. We first focus on the role of traditional populations in conservation and land use planning (socio-environmental model). We contrast this with the post-environmental development model that currently dominates the land use dynamics of Amazonia and which is in stark contrasts with previous advances in environmental protection, whose basis was sustainable use of resources and social participation. The future of the socio-environmental model appears uncertain and its recovery and long-term maintenance to underpin sustainable development will depend on the strengthening the participation of the civil societal sectors that are able to reestablish balance to the sustainability agenda in the region.