Quantitative and qualitative loss of tomato fruits during mechanized harvest

The use of mechanization in the harvesting of industrial tomatoes provides greater yield and speed of this stage. However, mechanical intervention in this process may alter the physiology of harvested fruits. Therefore, the objective of this study was to measure the quantitative losses of tomato fruits and to verify the physico-chemical behavior of fruits harvested based on physicochemical analysis in harvesters with different hours of use. Three self-propelled harvesters of the same brand and model with different working hours were used. Manually selected or undamaged fruits were harvested; afterwards, mechanized harvesting was carried out. Firmness, titratable acidity, soluble solids content (°Brix), pH, weight loss and fruit status classification proposed by the Ministry of Livestock, Agriculture and Food Supply of 2002 were evaluated. Quantitative losses were divided into: losses on vines, losses on soil and total losses. It was found that the number of hours worked by the harvester did not affect the quantitative losses. The amount of overall damage in a certain amount of fruit is greater when the harvester has a greater number of hours worked. Mechanized harvesting affected the physical attributes of the fruits, such as firmness and percentage of weight loss.O uso da mecanização na colheita do tomate industrial proporciona maior rendimento e rapidez desta etapa. Entretanto, a intervenção mecânica nesse processo pode alterar a fisiologia dos frutos colhidos. Portanto, objetivou-se com o trabalho mensurar em colhedoras, com diferentes horas de uso, as perdas quantitativas de frutos de tomate e verificar o comportamento físico-químico dos frutos colhidos a partir de análises físico-químicas. Foram utilizadas três colhedoras autopropelidas da mesma marca e modelo com diferentes números de horas de trabalho. Colheu-se os frutos manualmente selecionados ou sem danos; posteriormente, realizou-se a colheita mecanizada. Foram avaliados a firmeza, acidez titulável, teor de sólidos solúveis (°Brix), pH, perda de massa e a classificação quanto ao estado dos frutos proposta pelo Ministério da Agricultura Pecuária e Abastecimento de 2002. As perdas quantitativas foram divididas entre: perdas nas ramas, perdas no solo e perdas totais. Foi constatado que o número de horas trabalhadas pela colhedora não influiu nas perdas quantitativas. A quantidade de danos gerais em uma determinada quantidade de frutos é maior quando a colhedora possui um maior número de horas trabalhadas. A colheita mecanizada afetou os atributos físicos dos frutos, tais como a firmeza e a porcentagem de perda de massa

Dynamic traction of a mechanized set based on technical and operational parameters

The objective of this study was to evaluate and model the traction performance parameters of a tractor 4x2 FWD, according to the tractor speed, the internal pressure and the type of tires construction. For each type of tire construction was assembled an experiment in which we evaluated the influence of internal pressures of the front and rear tires and the speed of the mechanical assembly. It was found that the sliding of the diagonal run, presented significant effect in all variables analyzed, since the radial showed no influence of the factors evaluated. The power available in the drawbar was higher when the tractor was equipped for radial tires. The response variables, fuel consumption schedule and specific fuel consumption were more sensitive to the speed of the internal tire pressure. The fuel consumption per area worked, did not affect the analyzed variables. As for the effort prediction models in the tractor drawbar, it was only possible for diagonal run, which are influenced by speed and internal pressure levels of the front and rear tires

Expanding tropical forest monitoring into Dry Forests: The DRYFLOR protocol for permanent plots

This is the final version. Available on open access from Wiley via the DOI in this recordSocietal Impact Statement Understanding of tropical forests has been revolutionized by monitoring in permanent plots. Data from global plot networks have transformed our knowledge of forests’ diversity, function, contribution to global biogeochemical cycles, and sensitivity to climate change. Monitoring has thus far been concentrated in rain forests. Despite increasing appreciation of their threatened status, biodiversity, and importance to the global carbon cycle, monitoring in tropical dry forests is still in its infancy. We provide a protocol for permanent monitoring plots in tropical dry forests. Expanding monitoring into dry biomes is critical for overcoming the linked challenges of climate change, land use change, and the biodiversity crisis.Newton FundNatural Environment Research Council (NERC)Fundação de Amparo à Pesquisa do Estado de São PauloCYTE