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A produção do café no estado do Espírito Santo é uma atividade de grande importância para o estado e, com isso, diversas técnicas têm sido utilizadas para ampliar e melhorar essa atividade desde o planejamento até a comercialização do produto. Diante disso, objetivo do trabalho consiste em avaliar, em ambiente SIG, parâmetros como Clorofila, NDVI e Incidência Solar através de uma análise hierárquica de processos (AHP) com o propósito de estimar a atividades das enzimas do grupo oxiredutases, como a peroxidase (POD) e a polifenoloxidases (PPO), além das proteínas dos vegetais, no plantio de café do Centro de Ciências Exatas, Naturais e da Saúde da Universidade Federal do Espírito Santo. Para isso, foi utilizado o software ArcGis (2014) e dois dados rasters: (i) Imagem SRTM com resolução horizontal de 30-90m para extração dos dados de declividade, incidência solar e altimetria; (ii) Imagem RapidEye datada de julho de 2013 com precisão de 5-6,5m para extração dos dados de NDVI e Clorofila. Destaca-se nos resultados, que a análise hierárquica de processos se mostrou favorável para avaliar uma área representada por uma superfície de pixel que mede o grau de atividade de enzima oxirredutase entre 0 e 255, apresentando resultados similares com outros trabalhos realizados na área experimental do CCENS-UFES. Para um resultado mais preciso em ambiente SIG, seria necessário utilizar dados de um modelo digital de elevação de alta precisão ou similar as imagens do sensor RapidEye, já que um dos fatores importantes (incidência solar) é dependente desse dado.

Received: January 19th, 2021 ; Accepted: May 20th, 2021 ; Published: October 5th, 2021 ; Correspondence: paricia.ponciano@ufla.br The concept of environmental sustainability has been seeking a way to develop projects that reduce the impacts provided by agricultural development and the excessive consumption of natural resources. However, there is still little knowledge about the acoustic insulation/absorption behaviour of lignocellulosic materials. Hence, this study aimed to evaluate the acoustic properties of five cement panels reinforced with the following lignocellulosic materials: eucalyptus, sugarcane bagasse, coconut shell, coffee husk, and banana pseudostem, which ones have as a reference a commercial plaster used as sealing in civil constructions. The proposed panels were produced with each lignocellulosic material residue. It was produced three replicates for each type including plaster (being 18 panels in total). The sound insertion loss (SIL) measurement of the above-mentioned panels have been performed using an acoustical treated inexpensive facility developed based on the literature. The characterization of the acoustic behaviour of the studied materials were analysed according to the IEC (61260-1). The acoustic measurements have been done in the range of 20 Hz to 20 kHz and the analysis in octave bands have been performed. To make the analysis easier, the overall range of frequencies mentioned above was divided as ‘low’, ‘middle’ and ‘high’ ranges. Additionally, the measurement of thickness, density and porosity structure parameters of the lignocellulosic samples have been performed. According to the results and doing a trade-off analysis, the eucalyptus presented the overall best performance considering the overall range of analysis, being the banana pseudostem and sugarcane bagasse materials as good competitors.

Article New techniques for analysing the earth's surface have been explored, such as the use of remotely piloted aircraft (RPA) to obtain aerial images. However, one of the obstacles of photogrammetry is the reliability of the scenes, because in some cases, considerable geometric errors are generated, thus necessitating adjustments. Some parameters used in these adjustments are image overlaps and control points, which generate uncertainties about the amount and arrangement of these points in an area. The aim of this study was to test the potential of a commercial RPA for monitoring and its applicability in the management of and decision-making about coffee crops with two different overlaps and to evaluate geometric errors by applying four grids of georeferenced points. The study area is located in an experimental Arabica coffee plantation measuring 0.65 ha. To capture the images, the flight altitude was standardized to a 30 m altitude from the ground, and a constant travel speed of 3 m s -1 was used. The treatments studied were two combinations of image overlap, namely, 80/80% and 70/60%. Six points were tracked through Global Navigation Satellite System (GNSS) receivers and identified with signs, followed by an RPA flight for image collection. The obtained results indicated distinct residual error rates pointing to larger errors along Cartesian axis Y, demonstrating that the point distribution directly affects the residual errors. The use of control points is necessary for image adjustments, but to optimize their application, it is necessary to consider the shape of the area to be studied and to distribute the points in a non-biased way relative to the coordinate axes. It is concluded that the lower overlap can be recommended for use in the flight plan due to the high resolution of the orthomosaic and the shorter processing time.