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The lack of error of experimental planning in agricultural field studies can result in rework, causing the waste of financial resources. The determination of the optimal size of the experimental plot for carrying out the treatments can minimize these problems. The objective of this paper was to estimate the optimal plot size for measuring reflectance in soybeans, without treatment, using the modified maximum curvature method and the maximum distance method. Reflectance readings were taken in the soybean crop with the aid of the GreenSeeker® equipment, in basic experimental units of 0.45 m², in an area of 7 lines and 8 meters in length. The data were collected in three phenological stages of soy (R4, R5.5 and R6), obtaining 63 simulations of experimental area in each stage. Based on the results, it is recommended to use plots of 7.20 m², with grouping of 4 lines of 4 m in length.

Spectral remote sensing and proximal sensors are important tools for managing the plant-pathogen relationship. The lack of experimental planning and the probability of error in agricultural studies may result in work repetition and, consequently, in financial expenses and costs with human resources. To reduce such problems, determining the optimum size of the experimental plot for treatments is one of the adopted methods. The objective of this study was to estimate the optimum plot size for reflectance in soybeans that were treated with different fungicide levels according to the methods of modified maximum curvature and maximum distance. Reflectance readings were carried out for the soybean crop with a radiometer GreenSeeker®, considering basic units of 0.45 m² in an area of ten rows, 10 m long, for each treatment. Treatments were applied to create a gradient of Asian soybean rust, varying the number of fungicide applications. Data were collected in two phenological stages (R5.5 and R6), obtaining 300 simulations of experimental area for each stage. Based on the results, the use of 5.40 m² plots with a group of three rows, 4 m long, is recommended. RESUMO O sensoriamento remoto espectral e o sensor proximal são ferramentas importantes para gerenciar a relação planta-patógeno. A falta de planejamento experimental e a probabilidade de erro em estudos agrícolas podem resultar em retrabalho e, consequentemente, despesas financeiras e de recursos humanos. Uma maneira de reduzir esse problema é determinar o tamanho ótimo de parcela experimental para realização dos tratamentos. O objetivo deste estudo foi estimar o tamanho ótimo de parcela para refletância em soja que foi tratada com diferentes doses de fungicida, usando os métodos de curvatura máxima modificada e distância máxima. As leituras de refletância foram realizadas na cultura de soja com o auxílio de um radiômetro GreenSeeker®, com unidades básicas de 0,45 m², em uma área de dez linhas, com 10 metros de comprimento, em cada tratamento. Os tratamentos foram aplicados para criar um gradiente da doença ferrugem asiática da soja, variando o número de aplicações de fungicidas. Os dados foram coletados em dois estágios fenológicos (R5.5 e R6), obtendo-se 300 simulações de áreas experimentais em cada estágio. Com base nos resultados, recomenda-se o uso de parcelas de 5,40 m², com um grupo de três linhas, com 4 m de comprimento.

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. info:eu-repo/semantics/publishedVersion

When associated with polymer blends, starch may improve the biodegradability and compostability of other materials. The objectives of this work were to evaluate the abiotic hydrolysis and the composting process of films obtained from polymer blends between thermoplastic starch (TPS) and three other biodegradable polymers: poly[(butylene adipate)- co -(terephthalate)] (PBAT), poly(lactic acid) (PLA) and polyvinyl alcohol (PVA). PVA/TPS stood out as the most homogeneous blend and the one that showed the highest weight loss, with 46.21% of its initial weight remaining after abiotic hydrolysis tests. On the other hand, PBAT/TPS and PLA/TPS underwent more drastic and rapid degradation during composting in contrast to PVA/TPS. They became very fragmented after 21 days of composting, while the PVA/TPS was visually modified but remained unbroken until day 70. No blend sample exerted negative effects on the quality of the compost.

The open burning of municipal solid waste (MSW) –frequently observed in developing countries– emits harmful pollutants, including fine particulate matter (PM2.5) and black carbon (BC), and deteriorates the air quality in urban areas. This work reports on PM2.5 and BC measurements (fixed and mobile) conducted in a residential neighborhood on the outskirts of a Brazilian city (Londrina), complemented by a public opinion survey to understand the open burning in the context of waste management. Mean (± standard deviation) BC concentration (1.48 ± 1.40 μg m−3) at the fixed sites of the neighborhood was lower than downtown, while PM2.5 (9.68 ± 8.40 μg m−3) concentration was higher. The mobile monitoring showed higher mean PM2.5 concentrations but lower BC/PM2.5 ratios than downtown, with sharp and fast spikes (up to 317.87 and 565.21 μg m−3 for BC and PM2.5, respectively). The large spatial heterogeneity of particulate concentrations was associated with the occurrence of MSW burning events. Our observations were verified by the survey respondents who identified poor waste management practices: garbage in streets, waste burning, and illegal dump sites. Even though the area has a municipal waste collection service, the majority of the respondents (87%) had seen waste burning close to their homes on a weekly basis, and think that people burn waste out of habit (54%) and because they are not patient to wait for the collection services (67%). To combat this illegal practice, we suggest raising the public awareness through campaigns at local level, adopting education initiatives and economic incentives for correct waste segregation, and enforcing regular inspection of burning events by the authorities. Our research method proved to be a time- and cost-effective approach for mapping particulate concentrations and for identifying undesirable waste practices, and could be effectively applied to other global cities.

Composting is a technique used to obtain a nutrient-rich, plant-like organic compost. Considering that there are few studies that shows the efficiency of these composts in the cultivation of vegetables, the objective of this study was to evaluate, in the cultivation of lettuce, the quality of the final compost obtained from tree pruning, dairy sludge and coffee grounds—compost 1; grass, dairy sludge and coffee grounds—compost 2; grass, dairy sludge, coffee grounds and boiler ash—compost 3. Lettuce (Lactuca Sativa L.) were planted for the study with the three composts and a control object-without compost, and a portion with NPK fertilizer. The evaluated parameters were plant growth, head diameter, leaf number, dry mass and fresh mass. The results shows statistical similarities between the organic fertilizers and NPK fertilizer in the evaluated parameters and the control plot presented inferior results to the other plots, emphasizing the need for fertilization at each planting.

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 leafcover 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.

Equine breeders seek alternatives to properly allocate saturated beds produced during the confinement and composting and vermicomposting can be viable alternatives. However, it is not elucidated wh...

A indústria da construção civil é um dos setores da economia que apresenta os maiores índices de geração de resíduos. É de suma importância a correta gestão destes resíduos. Medidas para a avaliação da qualidade desta segregação auxiliam na tomada de decisão do gerador de resíduos. Os poucos métodos de avaliação existentes contam com grande subjetividade. Objetivou-se aprimorar um índice de qualidade de segregação (IQS) já existente em um software de gerenciamento de resíduos da construção civil, denominado Waste Manager (WM), com a proposição de um novo método para avaliar a qualidade da segregação das caçambas para a destinação final. Foram analisados dados do gerenciamento de resíduos de uma obra existentes no software WM e foram feitos levantamentos da real situação das caçambas. O novo método foi proposto adicionando dados de densidade das caçambas e não conformidades observadas. Além disso, este novo método foi aplicado à realidade da obra estudada e os resultados foram comparados ao método já existente. Foi possível concluir que o novo método é mais criterioso, além de representar mais a realidade das caçambas, visto que a avaliação passa a ser menos subjetiva, recomendando-se, portanto, sua aplicação nas obras para a determinação do IQS.

One of the main analytical variable to indicate the evolution and the phases of the composting process is temperature, whose constant monitoring is fundamental for decision making. However, studies usually perform collection of temperature data with a daily frequency due to the operational difficulty in obtaining this information from manually collected samples. Thus, the aim of this study was to determine the ideal frequency of temperature data collection in composting layers. Eight composting layers containing tree prunings + domestic organic residues were installed and four temperature sensors were installed in each layer. The temperature data were collected and recorded from minute to minute by means of a datalogger developed with an Arduino board during 70 days of composting. Thus, the collected temperatures were used as a pilot sample, and therefore the ideal temperature collection rate was estimated for different estimation error limits. No significant difference was found between the different collection times according to the Kruskal-Wallis test at a significance level of 5%. Therefore, the ideal collection frequency can be determined from the error limit of temperature estimation that is acceptable to the researcher.

Instituições públicas federais devem implantar a Coleta Seletiva Solidária, conforme o Decreto n. 5940/2006. Objetivou-se levantar o nível de entendimento da comunidade acadêmica da Universidade Tecnológica Federal do Paraná (UTFPR), Campus Londrina acerca da Coleta Seletiva Solidária e sua avaliação quanto ao processo de implantação. Foram aplicados 422 questionários a alunos, professores e técnicos administrativos, totalizando 43% da população total. Percebeu-se a necessidade de intensificação de ações de sensibilização ambiental de modo a promover, gradativamente, o difícil processo de mudança de comportamento, tão necessário para a completa adesão e funcionamento de um programa de Coleta Seletiva Solidária institucional. PERCEPÇÕES SOBRE A COLETA SELETIVA SOLIDÁRIA NA UTFPR CÂMPUS LONDRINA

O objetivo do estudo foi avaliar o comportamento da decomposição da matéria orgânica e das minhocas da espécie Eisenia foetida em processo de vermicompostagem de dejetos ovinos e bovinos com palha de cana-de-açúcar, comparando duas relações iniciais de C:N (19:1 e 30:1). Para o procedimento experimental foram testadas as seguintes composições de resíduos: T1 (30:1 – Dejeto ovino + palha de cana-de-açúcar), T2 (19:1 – Dejeto ovino + palha de cana-de-açúcar), T3 (30:1 – Dejeto bovino + palha de cana-de-açúcar), T4 (19:1 – Dejeto bovino + palha de cana-de-açúcar) e T5 (30:1 – Dejeto ovino + dejeto bovino + palha de cana-de-açúcar). O processo de pré-compostagem foi conduzido ao longo de 34 dias. Em seguida, foram inseridas 24 minhocas em cada um dos vermirreatores, onde permaneceram por 58 dias. Em ambos os processos monitorou-se parâmetros físico-químicos e microbiológicos. Na vermicompostagem, monitorou-se ainda o desenvolvimento das minhocas. Ao final da pré-compostagem as análises microbiológicas mostraram a sanitização quanto à bactéria da espécie E.coli para todos os tratamentos. Na vermicompostagem os valores das relações C:N reduziram-se em todos os tratamentos, indicando a maturação dos compostos. O T4 foi o que apresentou desempenho menos satisfatório frente a todos os parâmetros físico-químicos monitorados, não sendo recomendado para aplicação em larga escala.

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 application of swine wastewater to the soil for agricultural purposes results in the addition of total and dissolved organic matter to the soil, which may interfere with the dynamics of pesticides in the soil. The objective of this study was to evaluate the effects of the application of total and dissolved organic matter from a biodigester and a treatment lagoon of swine wastewater in the adsorption and desorption of alachlor [2-chloro-2,6-diethyl-N(methoxymethyl acetamide)]. The assay was performed by the batch equilibrium method, and the results were fitted to the Freundlich model. The curve comparison test revealed a greater adsorption of alachlor in the soil treated with swine wastewater from the biodigester. The adsorption and desorption of alachlor increased in the soils where swine wastewater was added, and hysteresis was observed in all of the treatments.

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 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.