Yield prediction in banana (Musa sp.) using STELLA model

To overcome the challenges encountered in banana cultivation, such as the hig h cost of production due to high water consumption by the banana plant, efficient management practices are being adopted. The use of agricultural forecasting techniques is an alternative that has been gaining attention in rural areas. One way to manage and improve agricultural productivity is the use of technologies that allow the monitoring of production. The implementation of computational tools as software to aid processes, such as irrigation management, is gradually taking up space in the agricultural s ector . In this light, herein, the present study aimed to develop a model using STELLA 8.0 software to estimate the growth and productivity of irrigated banana ( Musa sp.). For this, the physiological processes and water demand were calculated using reference evapotranspiration (ET 0 ) and culture evapotranspiration (ET c ) in the first banana cycle for the climatic conditions of the Jaíba Project (Jaíba , M inas G erais Stat e, Brazil ). The data of the climatic conditions were obtained from the National Institute of Meteorology. It was verified that the average monthly ET 0 was 5.78 mm d ay - 1 . In addition, the water requirement of the plant corresponded to a blade equivalent to 65% of ET 0 . The verified productivity was 8.93 t ha - 1 , which is considered adequate for the simulated conditions. The model responded efficiently to the proposed application and was characterized as a prognostic tool of reality through simplified represent ationinfo:eu-repo/semantics/publishedVersio

Modeling of bell pepper growth under different water regimes

Os modelos computacionais têm se tornado ferramentas agregadoras ao processo de gestão agrícola, uma vez que fornecem a previsão de safras. Existem diversos softwares que são utilizados na elaboração de modelos agrícolas. O software STELLA pode ser utilizado para a modelagem agrícola. Este apresenta fácil aplicação e processos dinâmicos de interação entre variáveis ambientais, características da cultura e estimativa do balanço hídrico. Todavia, faz-se necessário à validação dos modelos, para que estes representem adequadamente o sistema físico. Partindo deste pressuposto, o objetivo desta pesquisa foi avaliar o uso do software STELLA na modelagem da cultura do pimentão, cultivado na Zona da Mata Mineira. Os dados de entrada referentes às variáveis climáticas foram obtidos da estação meteorológica automática localizada na área experimental. O experimento foi realizado na Universidade Federal de Viçosa, em dois ciclos, cujos dados obtidos foram divididos para calibração (1o ciclo) e validação (2o ciclo) do modelo. O primeiro ciclo ocorreu no ano de 2021 e o segundo em 2022, ambos com 98 dias após transplante (DAT). Foi utilizado o delineamento em blocos ao acaso com quatro níveis de reposição hídrica com base na evapotranspiração da cultura e três repetições. Foram analisadas a produção de matéria seca e o índice de área foliar. A concordância entre os modelos experimental e computacional foi verificada pelo teste “t” e índice “d”. Os valores modelados pelo STELLA foram estatisticamente iguais aos valores mensurados e houve concordância entre as técnicas estudadas. A utilização do software STELLA na modelagem da cultura do pimentão foi útil na simulação das características biométricas da planta e na estimativa do índice de área foliar. Palavras-chave: Irrigação deficitária. Manejo de Irrigação. Modelos de simulação.Computational models have become aggregating tools in the agricultural management process, as they provide crop forecasts. There are several software that are used in the elaboration of agricultural models. STELLA software can be used for agricultural modeling. This presents easy application and dynamic processes of interaction between environmental variables, crop characteristics and water balance estimation. However, it is necessary to validate the models, so that they adequately represent the physical system. Based on this assumption, the objective of this research was to evaluate the use of the STELLA software in the modeling of the pepper crop, cultivated in the Zona da Mata Mineira. The input data referring to the climatic variables were obtained from the automatic meteorological station located in the experimental area. The experiment was carried out at the Federal University of Viçosa, in two cycles, whose data obtained were divided for calibration (1st cycle) and validation (2nd cycle) of the model. The first cycle occurred in 2021 and the second in 2022, both with 98 days after transplantation (DAT). A randomized block design with four levels of water replacement based on crop evapotranspiration and three replications was used. Dry matter production and leaf area index were analyzed. The agreement between the experimental and computational models was verified by the “t” test and “d” index. The values modeled by STELLA were statistically equal to the measured values and there was agreement between the studied techniques. The use of STELLA software in the modeling of the pepper crop was useful in simulating the biometric characteristics of the plant and in estimating the leaf area index. Keywords: Deficit Irrigation. Irrigation Management. Simulation models.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPE

Modeling and validation of growth and corn production

O planejamento é fundamental para o sucesso da atividade agrícola. Atualmente, diversos softwares são utilizados pelos agricultores em vários países para esta finalidade. O STELLA é uma ferramenta computacional utilizada para simulação de uma infinidade de sistemas dinâmicos, podendo ser empregado na modelagem de culturas. Entretanto, para que os modelos representem adequadamente a realidade que ocorre em um sistema físico é imprescindível a validação dos mesmos nas condições ambientais que estão sendo modelados. Partindo dessa premissa, o objetivo neste estudo foi avaliar o uso do software STELLA na modelagem da cultura do milho híbrido DKB 390 PRO3, cultivado na Zona da Mata Mineira. Os dados de entrada referentes às condições climáticas foram obtidos junto ao Instituto Nacional de Meteorologia. O experimento foi realizado na Universidade Federal de Viçosa, com semeadura no dia 15 de outubro de 2019, seguindo o delineamento inteiramente casualizado, cujos tratamentos foram as dez avaliações realizadas durante o ciclo da cultura, com 40 repetições, nas quais foram analisadas a biomassa seca dos constituintes da planta, o índice de área foliar e a fotossíntese líquida. Os dados simulados e observados foram comparados por meio do teste “t” e do índice d, para verificar a igualdade e concordância entre os modelos. O rendimento dos grãos foi determinado para 13% de umidade. Os valores modelados pelo STELLA foram estatisticamente iguais aos valores mensurados e houve concordância entre as técnicas estudadas. Para as características massa seca de grãos, massa seca de raízes e índice de área foliar foram obtidos os melhores índices de concordância. A produtividade obtida foi alta, com valor de 13.236 kg ha -1 , sendo esta semelhante à produtividade simulada de 12.012 kg ha -1 . A modelagem da cultura do milho utilizando o software STELLA foi eficiente na simulação das características da planta. O modelo desenvolvido por meio do software STELLA mostrou-se uma tecnologia adequada para previsão do crescimento e da produtividade do milho, cultivado na Zona da Mata Mineira.Planning is critical to the success of agricultural activity. Currently, farmers in several countries use various software for this purpose. STELLA is a computational tool used to simulate a multitude of dynamic systems and can be used in modeling cultures. However, for models to adequately represent the reality that occurs in a physical system, it is essential to validate them in the environmental conditions that are being modeled. Based on this premise, the objective of this study was to evaluate the use of the STELLA software in the modeling of the hybrid corn crop DKB 390 PRO3, grown in Zona da Mata Mineira. The input data regarding the climatic conditions were obtained from the National Institute of Meteorology. The experiment was carried out at the Federal University of Viçosa, with sowing on October 15, 2019, following the completely randomized design, which were the ten evaluations carried out during the crop cycle, with 40 replicates, in which the dry biomass of plant constituents, leaf area index and liquid photosynthesis. The simulated and observed data were compared using the "t" test and the d index, to verify the equality and agreement between the models. Mineral yield was determined at 13% moisture. The values modeled by STELLA were statistically the same as the values measured and there was agreement between the techniques studied. For the characteristics of dry mass of grains, dry mass of roots and index of leaf area, obtained the best indices of agreement. The yield obtained was high, with a value of 13,236 kg ha -1 , which is similar to the simulated productivity of 12,012 kg ha -1 . Corn crop modeling using STELLA software was efficient in simulating plant characteristics. The model developed using the STELLA software proved to be a suitable technology to predict the growth and yield of maize grown in Zona da Mata Mineira.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Possible use of Si-Phytoliths in metal anomaly prospection. Example from Riacho dos Machado region, Cerrado, Minas Gerais, Brazil.

International audienceThis work investigates the distribution of selected heavy elements in soil samples and Si-Phytoliths from plants. The aim is to verify if metal contents are indicative for metal anomalies in the soil. Samples were collected in profiles near the Riacho dos Machados Goldmine. Granitic-gneissic rocks, in tectonized contact with the overlaying rocks, form the basis of the investigated region, which belongs to the Rio dos Machados Group of the Espinhaço Super Group. The whole rock substrate is covered by lateritic to arenitic soils with different exposure depths. Metal-rich fluid invaded this unit, forming metal anomalies, forming Zn-Pb-Au deposits, like that of Salobre-Porteirinha. After appropriate preparation, the samples were analyzed by ICP-OES (Si-Phytoliths) and XRF (soil). Anomalies in the investigated profile are indicated by high metal contents in the Si-Phytoliths of the selected species. Using different species, the metal concentration at different depths can be determined

Possible use of Si-Phytoliths in metal anomaly prospection. Example from Riacho dos Machado region, Cerrado, Minas Gerais, Brazil.

International audienceThis work investigates the distribution of selected heavy elements in soil samples and Si-Phytoliths from plants. The aim is to verify if metal contents are indicative for metal anomalies in the soil. Samples were collected in profiles near the Riacho dos Machados Goldmine. Granitic-gneissic rocks, in tectonized contact with the overlaying rocks, form the basis of the investigated region, which belongs to the Rio dos Machados Group of the Espinhaço Super Group. The whole rock substrate is covered by lateritic to arenitic soils with different exposure depths. Metal-rich fluid invaded this unit, forming metal anomalies, forming Zn-Pb-Au deposits, like that of Salobre-Porteirinha. After appropriate preparation, the samples were analyzed by ICP-OES (Si-Phytoliths) and XRF (soil). Anomalies in the investigated profile are indicated by high metal contents in the Si-Phytoliths of the selected species. Using different species, the metal concentration at different depths can be determined