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Um dos maiores desafios enfrentados pelas cidades brasileiras refere-se ao manejo adequado dos resíduos sólidos. A escola pode ser a interlocutora na sensibilização, direcionando o processo de ensino e aprendizagem para mudar o comportamento individual e coletivo de estudantes. Oficinas temáticas se caracterizam como uma intervenção pedagógica, em que a educação ambiental é abordada de forma dinâmica, interativa e criativa. Neste contexto, o estudo objetivou identificar as percepções de crianças em uma escola municipal de Cambé[1]PR acerca da temática dos resíduos sólidos, a partir de desenhos elaborados em uma oficina denominada de “Compostagem na escola”. A oficina foi conduzida por 11 estudantes de graduação do curso de Engenharia Ambiental da Universidade Tecnológica Federal do Paraná, acompanhados por uma professora coordenadora da ação. Empregou-se, como métodos de ensino: dinâmicas, jogos, conversas, todas com o intuito de integrar as crianças e promover a reflexão sobre o papel de cada uma no manejo adequado dos resíduos sólidos. Ao final, foi proposto para as crianças um questionário que continha a proposição de um desenho, de modo que pudessem retratar suas percepções acerca da temática de resíduos sólidos. A partir do olhar guiado pela Análise de Conteúdo, os desenhos foram classificados em três categorias: a) etapas e dinâmicas da oficinal; b) técnicas para gestão de resíduos sólidos; e c) forma de vida não humana na gestão de resíduos sólidos. A oficina foi uma estratégia de educação ambiental promissora, visto que se notou que quanto maior a interação e prazerosa a atividade, maior é o aprendizado.

O lodo da ribeira é um dos resíduos sólidos gerados nos curtumes e possui elevada carga orgânica, podendo causar impactos ao ambiente se disposto incorretamente. A compostagem pode ser utilizada para o tratamento deste resíduo. Recomenda-se, na literatura, que a relação C/N inicial do processo seja de 30:1. No entanto, esta relação pode ser inviável, visto que os resíduos considerados como fonte de nitrogênio são os maiores desafios das indústrias e gerados em maior quantidade. Objetivou-se avaliar a eficiência de duas relações C/N iniciais na compostagem do lodo de ribeira com poda de árvores e maravalha, na presença e na ausência da cinza de caldeira. Montou-se 16 leiras, com relação C/N inicial calculada de 16:1 e 12:1. Ao longo de 60 dias monitorou-se: pH, temperatura, condutividade elétrica, relação C/N, aspecto do material e redução de massa e volume. O pH de todos os compostos se apresentou alcalino. Apenas o T5 (lodo e poda, C/N 16:1) atingiu temperatura superior a 55ºC. Os tratamentos com poda de árvores foram mais eficientes quanto à redução da relação C/N, destacando-se T5 e T6 (lodo, poda e cinza, C/N 16:1) com 41,52 e 42,02% de redução, respectivamente. Todos os tratamentos sofreram redução de volume e massa, com destaque para T5 e T6. Houve maior descaracterização dos resíduos com poda de árvore em sua composição. Portanto, os compostos T5 e T6 se destacaram, evidenciando que a melhor relação C/N para iniciar o processo é 16:1, e a fonte de carbono é a poda de árvore.

ABSTRACT This study aimed to develop and validate the digital image processing software to quantify leaf coverage, employing the correlation of defoliation values and NDVI with various gradients of defoliation severity of the Asian soybean rust pathosystem. The digital images were obtained from the experiment conducted in 2013/2014. To conduct the experiment, 4 treatments (3 replicates) were adopted, considering the useful floor area of each plot (4 linear meters, 3 lines spaced at 0.45 m). The gradients of defoliation were obtained by treatment with fungicide to control Asian soybean rust. The quantification of the disease severity was performed through diagrammatic scale. The NDVI values were obtained using the GreenSeeker®, conducting the equipment above the plants. The digital photos were obtained in three heights and subsequently processed in software. Then the defoliation sampling was held in 10 plants through treatment. The image processing data correlated with defoliation (94.22%) and with NDVI (89.27%), and we also observed the correlation of defoliation with NDVI (96.12%). These data suggests the use of digital images as an alternative to quantify the vegetation cover, with the advantage of being a dynamic and fast method that does not require experience from the assessor to quantify soybean defoliation.

The sustainability of meat production systems has been highlighted by the impact on the environment and the conservation of natural resources. The aim of this manuscript is to provide a specific review of the environmental sustainability of beef production in a life cycle assessment (LCA) context. Questions about the main environmental impacts caused by beef production were discussed. The phases of the LCA were detailed as well as the main functional units, boundaries of the systems and categories of impacts used in recent studies. LCA is a fast, easy and intuitive method that correlates human activities and their environmental performance in different sectors, such as beef production.

The production of biopolymers has been shown to be one of the most viable alternatives for the reduction of the use of conventional plastics. The oat hulls are a by-product with great ability to be incorporated into the production of biopolymers since it is a lignocellulosic compound. The lignin present in its composition can improve the strength of the material, however, it can also hamper its degradation. The aim of this study was to evaluate the degradation levels of composites produced from starch and polylactic acid with absence (T1) and presence of oat hulls (T2) through the Sturm test. In T2 it was a more uniform and smooth biopolymer. In addition, the use of oat hulls favored CO2 production, 8% more than T1. Although the loss of dry mass in T1 was 3% higher, it was possible to observe degradation in T2.

Abstract The objectives of this work were to determine the biodegradability of starch/glycerol foam and of poly(butylene-adipate-co-terephthalate) (PBAT)/starch film using respirometric methods and also to compare these results with conventional polymers – expanded polystyrene and low-density polyethylene. A matured organic compost was utilized as inoculum and sucrose was used as positive reference material. Biodegradation efficiencies (BE) after 47 days were: 35% for sucrose; 34% for starch/glycerol; and 38% for PBAT/starch. Starch/glycerol and PBAT/starch presented BE statistically equal to sucrose, whilst both the conventional packaging used were not degraded (p> 0.05). Infrared spectroscopy and thermogravimetric analyses showed that the microbiota rather degraded the starch over the PBAT in the PBAT/starch blend, and also that some starch remained intact in the internal polymeric matrix. This study verified that starch/glycerol foam and PBAT/starch film are highly biodegradable materials and may then be used to enhance the biodegradability of some products such as disposable trays and supermarket bags.

O estudo analisou os resíduos sólidos domiciliares em diferentes formas de habitação: na cidade de Londrina-PR estudaram-se um condomínio vertical e um horizontal, e em Balneário Camboriú-SC um condomínio vertical. As características físicas analisadas foram: geração per capita, massa específica e composição gravimétrica. Os resultados demonstraram a variação na geração per capita dos diferentes condomínios estudados: em Londrina o condomínio vertical apresentou uma geração de 0,757 kg.hab-1.dia-1, enquanto no condomínio horizontal foi de 0,480 kg.hab-1.dia-1. Essa diferença pode estar relacionada ao poder aquisitivo dos moradores e seus hábitos de consumo. Por outro lado, no condomínio vertical de Balneário Camboriú obteve-se a geração de 0,916 kg.hab-1.dia-1. As massas específicas dos materiais recicláveis apresentaram grandes diferenças, entre 46,35-87,50 kg.m-3 para o papel, 18,75-34,72 kg.m-3 para o plástico, 20,84-28,47 kg.m-3 para o metal e 12,50-358,33 kg.m-3 para o vidro. Com isso, fica evidente a importância da determinação dessas características para fins de projeção de acondicionadores, áreas de transbordo temporário e sistema de coleta de resíduos.

The normalized difference vegetation index (NDVI) obtained via radiometer is important to determine the physiological state of plant, being a promising tool for decision making as to the best time for the application of agricultural pesticides, to analyze the threshold of economic damage. The use of drones with digital camera embedded in agriculture is in broad expansion. Through digital images analyzed in computer programs and correlated with NDVI it is possible to determine the leaf cover in plants. The aim of this study was to confirm the use of digital images at 30 m in height to determine the leaf cover, correlating them with NDVI values obtained on the ground. Therefore, 30 m height photos were taken with the help of a drone and three stages of maize development (N4, N8 and R1), which were considered as treatments; afterwards, the images were analyzed in software to survey the leaf cover. The NDVI data were obtained in the same areas at a height of 0.5 m from the crop canopy, and it were submitted to the Scott Knott Test at 5 % significance and Pearson correlation. There was no statistical difference between methods and the Pearson correlation coefficient value (0,952) confirms strong evidence for correlation between the two methods. Thus, it can be concluded that the use of drone with embedded digital camera has promising use for the determination of leaf cover in maize.

The study of composting technique becomes relevant to management of organic waste generated in an undertaking agricultural research. Therefore, this paper aimed to evaluate the efficiency of stabilization of organic matter in two composting systems: controlled (plowings and irrigations fortnightly) and natural. It has been tested two piles (controlled and natural) during 120 days in four treatments: soy straw (T1), wheat straw (T2), tree pruning (T3), mixture of soy and wheat straw and tree pruning (T4) with organic residues from the recycling program + soybeans. There was monitoring of temperature, moisture, pH, electrical conductivity (EC), C, N, C/N ratio and reduction of mass and volume. In the controlled treatments, the thermophilic phase was lower, the moisture was in the ideal ratio for the process (with lower values in the natural treatments), and there was a decrease of 3-4 times of the values of EC and the higher reductions of mass and volume. In all treatments, the values of pH were neutral and the C/N ratio declined 37-50%, assuming final values of matured composts. It has been concluded that regardless of mixtures of waste, the controlled treatments, in the period of 120 days, were more efficient in stabilize the organic material.

This study aimed at evaluating the effects of pig slurry application with mineral fertilizer on ions leaching from the soil in soybean crop. The experiment was carried out in 24 drainage lysimeters under protection. The soybean cultivar CD 202/COODETEC was sown in a soil that received 0, 100, 200 and 300 m³ha-1of pig slurry in one cycle, with or without mineral fertilizer. There were three samplings of soil throughout the trial to determine the pH, N, NO3-, K+, Ca2+, Mg2+, Na+, Cu+2, Zn+2, OM, CEC, EC and SAR six times during the crop cycle. The yield was determined in the plants. In soil, pig slurry increased the concentrations of pH, NO3-, K+, Zn+2, OM and CEC, while mineral fertilizer increased P and Zn+2concentrations. The limits observed for the leachate parameters did not present environmental problems according to the Brazilian legislation, but in the intermediate and long term, there special attention should be given to NO3-, P, Na+, EC and SAR. Soybean yield was higher with mineral fertilizer and increased with pig slurry application.

Os estudos da capacidade de adsorção de metais pesados em um solo podem ser empregados para avaliar a contribuição deste na contaminação de águas superficiais e subterrâneas. Este trabalho teve por objetivo estudar a adequação dos modelos de Langmuir e de Freundlich para descrever a adsorção de cobre em Latossolo Vermelho Distrófico úmbrico de textura argilosa. Para determinação da capacidade de adsorção de cobre no solo, utilizou-se 2,000g de solo adicionados de 10 mL de CaCl2 0,01 mol L-1 e 10 mL de soluções de CuCl2 em diferentes concentrações. A capacidade máxima de adsorção de cobre no solo, determinada pelo modelo de Langmuir, foi de 2,95 mg g-1. Além disso, os resultados demonstraram que o modelo de Freundlich apresentou melhor ajuste aos dados experimentais, simulando adequadamente a adsorção do cobre no solo em estudo.

The beef supply chain has multiple negative impacts on the environment. A method widely used to measure impacts from both the use of resources and the emissions generated by this sector is the life cycle assessment (LCA) (ISO 14040). This study aimed to evaluate a semi-intensive system (SIS) and an extensive organic system (EOS), combined with two different slaughterhouses located in the northeast of Portugal. The studied slaughterhouses are similar in size but differ in number of slaughters and in sources of thermal energy: natural gas (Mng) vs. biomass pellets (Mp). Four categories of environmental impact were evaluated: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), and photochemical ozone creation potential (POCP). As expected, higher impacts were found for SIS for all studied impact categories. Slaughterhouse activities, fertilizer production, and solid waste treatment stages showed little contribution when compared to animal production. Concerning the slaughterhouses activities, the main sources of environmental impact were the use of energy (electric and thermal) and by-products transportation.

As águas residuárias de suinocultura apresentam características físico-químicas que variam de acordo com o sistema de higienização das baias, estádio de desenvolvimento dos animais, alimentação, condições climáticas, genética, entre outros fatores. No Brasil, o tratamento dessas águas residuárias, com elevada carga poluente, ocorre, geralmente, em esterqueiras e biodigestores. Na maioria das propriedades rurais, o destino final dos efluentes tratados é o solo. Pratica-se, portanto, o reúso de água na agricultura, que pode interferir na dinâmica de diversos poluentes no solo, como é o caso dos pesticidas. As águas residuárias apresentam-se na forma total e dissolvida, sendo esta a fração mais investigada atualmente na dinâmica desses poluentes. Neste sentido, objetivou-se utilizar a técnica de espectroscopia na região do infravermelho médio com transformada de Fourier na caracterização da matéria orgânica total e dissolvida proveniente de águas residuárias de suinocultura tratadas em biodigestor e esterqueira. Nos resultados, não foi possível observar diferenças na composição das águas residuárias pela espectroscopia infravermelha com transformada de Fourier. Entretanto, pode-se identificar a presença de materiais ainda pouco degradados e a ocorrência de grupos funcionais nitrogenados, que apontam para a liberação do nitrogênio no solo quando degradados, evidenciando o potencial de reúso dessas águas residuárias na agricultura como forma de fertirrigação. Palavras-chave: Infravermelho. Esterqueira. Biodigestor. Efluentes.

This study evaluated the effects of total and dissolved organic matter produced from two swine wastewater treatment systems, a biodigester and a manure lagoon, on the adsorption, desorption, and leaching of alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) in soil. It was used the batch equilibrium method to test adsorption and desorption, and the results are presented in Freundlich isotherms. It also used disturbed soil columns to evaluate the miscible displacement of alachlor in soil treated with total and dissolved organic matter. This assay was used to monitor the concentration of alachlor in the leached material, the amount of total organic carbon, and the pH. The addition of swine wastewater promoted greater adsorption and desorption of alachlor compared with the control. The dissolved organic matter promoted less soil adsorption of alachlor compared with the total organic matter and also interacted with the alachlor and/or competed with the exchangeable cation sites in the soil, resulting in greater leaching. The total organic matter contributed to the emergence of new sorption sites in the soil column, and the solids present in the composition may have blocked pesticide passage, resulting in lower loss of alachlor due to leaching.