Morphology, yield and quality of greenhouse tomato cultivation with flexible photovoltaic rooftop panels (Almeria-Spain)

Los paneles fotovoltaicos flexibles son una opción para generar energía renovable que podría ser compatible con la producción de cultivos de invernadero, especialmente en países cálidos y soleados. El objetivo de este estudio fue evaluar, durante dos campañas de producción, el efecto de la sombra causada por paneles fotovoltaicos flexibles montados en el techo del invernadero (dos disposiciones) sobre la morfología de las plantas de tomate, producción y calidad de frutos. Este estudio se realizó durante dos años agrícolas en un invernadero comercial para la producción de tomate. Se analizaron dos conjuntos de paneles fotovoltaicos colocados en el techo del invernadero. Ambos ocuparon el 9,8% de la cobertura. Los parámetros estudiados fueron PAR, morfología de la planta, rendimiento del cultivo y calidad del fruto. Los resultados mostraron que la pequeña reducción de la radiación PAR provocada por los paneles fotovoltaicos flexibles en la cubierta no afectó a la producción total/comercial, morfología de las plantas, número de flores por rama, color, firmeza y pH del fruto; no obstante, el diámetro del fruto disminuyó, sin afectar a la producción comercial (kg·m-2). Ambas disposiciones de paneles fotovoltaicos flexibles en la cubierta del invernadero produjeron un efecto similar en la morfología de las plantas, producción y calidad de frutos

Compatibility between Crops and Solar Panels: An Overview from Shading Systems

The use of alternative energy in agricultural production is desired by many researchers, especially for protected crops that are grown in greenhouses with photovoltaic panels on the roofs. These panels allow for the passage of varying levels of sunlight according to the needs of each type of crop. In this way, sustainable and more economic energy can be generated than that offered by fossil fuels. The objective of this work is to review the literature regarding the applications of selective shading systems with crops, highlighting the use of photovoltaic panels. In this work, shading systems have been classified as bleaching, mesh, screens, and photovoltaic modules. The search was conducted using Web of Science Core Collection and Scopus until February 2018. In total, 113 articles from scientific journals and related conferences were selected. The most important authors of this topic are “Yano A” and “Abdel-Ghany AM”, and regarding the number of documents cited, the most important journal is Biosystems Engineering. The year 2017 had the most publications, with a total of 20, followed by 2015 with 14. The use of shading systems, especially of photovoltaic panels, requires more crop-specific research to determine the optimum percentage of panels that does not reduce agricultural production

Application of biostimulant products and biological control agents in sustainable viticulture : A review

Current and continuing climate change in the Anthropocene epoch requires sustainable agricultural practices. Additionally, due to changing consumer preferences, organic approaches to cultivation are gaining popularity. The global market for organic grapes, grape products, and wine is growing. Biostimulant and biocontrol products are often applied in organic vineyards and can reduce the synthetic fertilizer, pesticide, and fungicide requirements of a vineyard. Plant growth promotion following application is also observed under a variety of challenging conditions associated with global warming. This paper reviews different groups of biostimulants and their effects on viticulture, including microorganisms, protein hydrolysates, humic acids, pyrogenic materials, and seaweed extracts. Of special interest are biostimulants with utility in protecting plants against the effects of climate change, including drought and heat stress. While many beneficial effects have been reported following the application of these materials, most studies lack a mechanistic explanation, and important parameters are often undefined (e.g., soil characteristics and nutrient availability). We recommend an increased study of the underlying mechanisms of these products to enable the selection of proper biostimulants, application methods, and dosage in viticulture. A detailed understanding of processes dictating beneficial effects in vineyards following application may allow for biostimulants with increased efficacy, uptake, and sustainability

La calidad de agua en el río Daule

El Grupo de Investigación Interdisciplinar en Matemática Aplicada (GIIMA) de la Universidad Politécnica Salesiana, sede Guayaquil, se planteó un problema muy puntual para esta investigación: ¿cuál es la huella que ha dejado el ser humano en el río Daule? Para responder a ese cuestionamiento han trabajado algunas variables e indicadores. La variable dependiente de investigación es la calidad del agua, siendo los indicadores más importantes de investigación las concentraciones de hierro, arsénico, sólidos totales, pH, temperatura y turbidez. La variable independiente son los factores demográficos, tales como densidad poblacional, migración y longevidad. Un importante estudio de caso que nos habla del impacto del ser humano en la naturaleza y el entorno