Greenhouse gas balance due to the conversion of sugarcane areas from burned to green harvest, considering other conservationist management practices

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mitigation of N2O emissions from grassland by nitrification inhibitor and actilith F2 applied with fertilizer and cattle slurry

Nitrous oxide (N2O) is involved in both ozone destruction and global warming. In agricultural soils it is produced by nitrification and denitrification mainly after fertilization. Nitrification inhibitors have been proposed as one of the management tools for the reduction of the potential hazards of fertilizer-derived N2O. Addition of nitrification inhibitors to fertilizers maintains soil N in ammonium form, thereby gaseous N losses by nitrification and denitrification are less likely to occur and there is increased N utilization by the sward. We present a study aimed to evaluate the effectiveness of the nitrification inhibitor dicyandiamide (DCD) and of the slurry additive Actilith F2 on N2O emissions following application of calcium ammonium nitrate or cattle slurry to a mixed clover/ryegrass sward in the Basque Country. The results indicate that large differences in N2O emission occur depending on fertilizer type and the presence or absence of a nitrification inhibitor. There is considerable scope for immediate reduction of emissions by applying DCD with calcium ammonium nitrate or cattle slurry. DCD, applied at 25 kg ha-1, reduced the amount of N lost as N2O by 60% and 42% when applied with cattle slurry and calcium ammonium nitrate, respectively. Actilith F2 did not reduce N2O emissions and it produced a long lasting mineralization of previously immobilized added N.

Análise do risco de ocorrência da monilíase em cacaueiro no Brasil face às mudanças climáticas globais

The aim of this study was to evaluate the potential risk of moniliasis occurrence and the impacts of climate change on this disease in the coming decades, should this pathogen be introduced in Brazil. To this end, climate favorability maps were devised for the occurrence of moniliasis, both for the present and future time. The future scenarios (A2 and B2) focused on the decades of 2020, 2050 and 2080. These scenarios were obtained from six global climate models (GCMs) made available by the third assessment report of Intergovernmental Panel on Climate Change (IPCC). Currently, there are large areas with favorable climate conditions for moniliasis in Brazil, especially in regions at high risk of introduction of that pathogen. Considering the global warming scenarios provided by the IPCC, the potential risk of moniliasis occurrence in Brazil will be reduced. This decrease is predicted for both future scenarios, but will occur more sharply in scenario A2. However, there will still be areas with favorable climate conditions for the development of the disease, particularly in Brazil's main producing regions. Moreover, pathogen and host alike may undergo alterations due to climate change, which will affect the extent of their impacts on this pathosystem.

Impact of climate change on the phoma leaf spot of coffee in Brazil

The potential impact of global climate change on the spatial-temporal distribution of phoma leaf spot of coffee in Brazil was evaluated. Maps were prepared with the favorability of the climate to the occurrence of the disease in the current period and future. The future scenarios used were centered for the decades of 2010-2030, 2040-2060, and 2070-2090 (scenarios A2 and B2). These scenarios were obtained from six global climate models (GCM's) provided by the Intergovernmental Panel on Climate Change (IPCC). Assuming the future scenarios outlined by the IPCC, a reduction will occur in the occurrence of climatic favorability of phoma leaf spot in Brazil in both future scenarios (A2 and B2). As with the temporal distribution, the period of greatest risk of phoma leaf spot will tend to diminish in future decades. These planned changes will be larger in the A2 scenario compared to the predicted scenario B2. Despite the decrease in the favorability of phoma leaf spot in the country, some regions still present a potential risk of this disease. Furthermore, the increased frequency of extreme weather was not taken in to account. These will certainly influence the magnitude of potential impacts of climate change on the phoma leaf spot in Brazil.

Carbon dioxide emissions under different soil tillage systems in mechanically harvested sugarcane

Soil tillage and other methods of soil management may influence CO 2 emissions because they accelerate the mineralization of organic carbon in the soil. This study aimed to quantify the CO2 emissions under conventional tillage (CT), minimum tillage (MT) and reduced tillage (RT) during the renovation of sugarcane fields in southern Brazil. The experiment was performed on an Oxisol in the sugarcane-planting area with mechanical harvesting. An undisturbed or no-till (NT) plot was left as a control treatment. The CO2 emissions results indicated a significant interaction (p < 0.001) between tillage method and time after tillage. By quantifying the accumulated emissions over the 44 days after soil tillage, we observed that tillage-induced emissions were higher after the CT system than the RT and MT systems, reaching 350.09 g m-2 of CO2 in CT, and 51.7 and 5.5 g m-2 of CO2 in RT and MT respectively. The amount of C lost in the form of CO2 due to soil tillage practices was significant and comparable to the estimated value of potential annual C accumulation resulting from changes in the harvesting system in Brazil from burning of plant residues to the adoption of green cane harvesting. The CO 2 emissions in the CT system could respond to a loss of 80% of the potential soil C accumulated over one year as result of the adoption of mechanized sugarcane harvesting. Meanwhile, soil tillage during the renewal of the sugar plantation using RT and MT methods would result in low impact, with losses of 12% and 2% of the C that could potentially be accumulated during a one year period. © 2013 IOP Publishing Ltd.

O potencial da agroenergia no Brasil na mitigação do clima: histórico jurídico

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Modelagem de nicho ecológico de anuros da Mata Atlântica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

REDD+ no Estado do Pará: a política ambiental climática paraense no contexto nacional e internacional

A inserção do mecanismo de Redução de Emissões por Desmatamento e Degradação Florestal (REDD) no contexto do ordenamento jurídico-normativo e institucional do Estado do Pará, é a temática abordada pelo presente trabalho. A metodologia aplicada na presente pesquisa se baseou em duas técnicas de coletade dados, quais sejam o levantamento documental e a aplicação de questionário estruturado junto aos órgãos estaduais responsáveis pela articulação e implementação desse mecanismo no território paraense. De recente surgimento no cenário das discussões internacionais sobre meio ambiente e mudanças climáticas globais, levadas a efeito no âmbito da Convenção-Quadro das Nações Unidas sobre Mudança do Clima, o REDD se apresenta como proposta de desmatamento evitado para os países em desenvolvimento, cuja preservação do patrimônio florestal, em vista dos potenciais benefícios para a mitigação do aquecimento global, deveria ser compensado por meio da remuneração de indivíduos, comunidades, projetos e países, conforme a proposta originalmente lançada no ano de 2005, durante a COP 11, realizada em Montreal, no Canadá. Nesse contexto, o Estado do Pará, que encerrou o ano de 2012 como líder nos números de desmatamento entre os Estados da Amazônia Legal, ainda em 2009 previu a inserção do mecanismo de REDD no quadro jurídico regulatório e institucional paraense como parte das ações do (Decreto Estadual nº 1.697/2009). Decorrida a primeira fase de execução do Plano, qual seja o interstício de agosto de 2009 a agosto de 2012, verificou-se que osprocessos decisórios para implementação do mecanismo não avançaram, em que pese a existência de projetos dessa natureza em curso no território paraense, e o avanço dos demais Estados amazônicos quanto à temática, cujos arcabouços normativos já dispõem de políticas públicas atinentes ao REDD e REDD+ e importantes medidas adicionais correlatas, a exemplo da regulação sobre pagamento de serviços ambientais e políticas estaduais sobre mudanças climáticas.

Desenvolvimento de um tribômetro, tipo cilindro sob disco, para ensaios tribológicos em formulações com óleos vegetais

Pós-graduação em Engenharia Mecânica - FEIS

Using phenology to assess urban heat islands in tropical and temperate regions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aquecimento global e acidificação oceãnica: efeitos da temperatura, salinidade e dióxido de carbono no desenvolvimento larval do caranguejo intertidal Eriphia gonagra (Crustacea, Decapoda, Eriphiidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy

Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SUM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SUM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SUM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application. (C) 2014 Elsevier B.V. All rights reserved.

Estimativa dos impactos das mudanças climáticas na distribuição das espécies montanas do gênero Brachycephalus (Amphibia: anura) através da modelagem de nicho ecológico

The genus Brachycephalus is endemic to the Atlantic rainforest and is distributed mainly in the southeastern and southern Brazil. Currently, it has 17 recognized species, most of them, associated with mountainous habitats along the Serra do Mar and Serra da Mantiqueira ridges. Here we use an ecological niche modelling approach based on climatic variables, to assess the potential niche of the mountainous species of this genus. The model generated was then projected to future scenarios considering the last IPCC report, in order to estimate the impacts of climate changes on these species distribution. Results show a decrease in the total suitable area for the mountainous Brachycephalus species, as well as tendencies already observed for other organisms, such as, pole and upward migrations. A southern area on Planalto de Paranapiacaba increases in suitability for these species. We suggest special efforts on new surveys and conservation on the northern part of their distribution, once this seems to be the region more affected by climate changes on the projected scenarios

Mudanças climáticas: o discurso da mídia sobre o aquecimento global

This research is aimed at discussing the ways in which social agents influence global warming, analyzing the discourse of social actors involved in the debate on climate change, since there is a wide divergence in the scientific community about how man is able to modify the climate on a global scale. In fact the debate that permeates the issues beyond the limits of science and enter into a political-economic framework that takes extraordinary proportions. This emphasis can be very unscientific in the fundamental design concepts, or even creating a trivialization of the media. The main way to convey these concepts is to disclose them in the media, but the media has enormous power to transform the concepts and often manipulate the news by creating a common sense goes against the interests of the scientific community. Thus was conducted extensive research in major newspapers and magazines that move in the country. We surveyed the first two papers which were: “Folha de S. Paulo” and “O Estado de S. Paulo”, during the period from January 2000 to December 2008, totaling 3285 units for the newspaper Folha and 2555 for the newspaper Estadão. Subsequently a survey was made of data published in two journals that move at the national level, and these are the magazines VEJA and ÉPOCA for the same period. By performing these steps, it was concluded that several factors involving the media and climate change, such as topic relevance, types of approaches, perspectives of analysis, the staff development, supplies, among other factors of utmost importance for building news. As a result we can say that the media in fulfilling its role of mediator scientific, disclosing only a vision that permeates the scientific debate. The newspaper media, especially newspapers, has an informative and instantaneous. Often this preoccupation...(Complete abstract, click electronic access below)

Methane emission from soil under long-term no-till cropping systems

Methane (CH4) emission from agricultural soils increases dramatically as a result of deleterious effect of soil disturbance and nitrogen fertilization on methanotrophic organisms; however, few studies have attempted to evaluate the potential of long-term conservation management systems to mitigate CH4 emissions in tropical and subtropical soils. This study aimed to evaluate the long-term effect (>19 years) of no-till grass- and legume-based cropping systems on annual soil CH4 fluxes in a formerly degraded Acrisol in Southern Brazil. Air sampling was carried out using static chambers and CH4 analysis by gas chromatography. Analysis of historical data set of the experiment evidenced a remarkable effect of high C- and N-input cropping systems on the improvement of biological, chemical, and physical characteristics of this no-tilled soil. Soil CH4 fluxes, which represent a net balance between consumption (-) and production (+) of CH4 in soil, varied from -40 +/- 2 to +62 +/- 78 mu g C m(-2) h(-1). Mean weighted contents of ammonium (NH4+-N) and dissolved organic carbon (DOC) in soil had a positive relationship with accumulated soil CH4 fluxes in the post-management period (r(2) = 0.95, p = 0.05), suggesting an additive effect of these nutrients in suppressing CH4 oxidation and stimulating methanogenesis, respectively, in legume-based cropping systems with high biomass input. Annual CH4 fluxes ranged from -50 +/- 610 to +994 +/- 105 g C ha(-1), which were inversely related to annual biomass-C input (r(2) = 0.99, p = 0.003), with the exception of the cropping system containing pigeon pea, a summer legume that had the highest biologically fixed N input (>300 kg ha(-1) yr(-1)). Our results evidenced a small effect of conservation management systems on decreasing CH4 emissions from soil, despite their significant effect restoring soil quality. We hypothesized that soil CH4 uptake strength has been off-set by an injurious effect of biologically fixed N in legume-based cropping systems on soil methanotrophic microbiota, and by the methanogenesis increase as a result of the O-2 depletion in niches of high biological activity in the surface layer of the no-tillage soil. (C) 2012 Elsevier B.V. All rights reserved.