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Resumen Introducción. En Colombia, la producción hortícola en el trópico bajo es limitada principalmente por factores bióticos como el ataque de plagas, patógenos y factores abióticos como valores extremos de temperatura, radiación solar, viento y precipitación. Objetivo. Evaluar dos tipos de mallas anti-insecto en las áreas de ventilación de un invernadero colombiano ventilado de formado natural con el fin de analizar el efecto sobre las tasas de ventilación y el microclima generado. Materiales y métodos. El Estudio se desarrolló en el año 2019 en el departamento de Magdalena, Colombia. El enfoque metodológico incluyó el uso de modelo computacional de fluidos (CFD) 2-D para el desarrollo de quince simulaciones en estado estacionario, el modelo CFD fue validado experimentalmente en el prototipo del invernadero real evaluado. Resultados. Los parámetros de bondad de ajuste entre los datos medidos y simulados mostraron valores de error medio absoluto (MAE) y la raíz del error cuadrático medio (RMSE) para la temperatura y la humedad relativa de 0,15 y 0,32 °C, 2,41 y 2,73 %, respectivamente. Hubo una reducción promedio de las tasas de ventilación entre 55,3 y 77,1 % en comparación con el escenario de referencia que no incluyó la presencia de mallas anti-insecto, esta reducción generó modificaciones en el comportamiento de las variables temperatura y humedad relativa en el interior del invernadero, con una marcada distribución espacial heterogénea. Conclusión. Las condiciones micro climáticas más inadecuadas se presentaron en escenarios de baja velocidad de viento exterior, por lo tanto, es recomendable seleccionar e implementar algún tipo de malla anti-insecto en las áreas de ventilación de un invernadero basado en el comportamiento local de esta variable. Abstract Introduction. In Colombia, horticultural production in the low tropics is limited mainly by biotic factors such as pest attacks, pathogens, and abiotic factors such as extreme values of temperature, solar radiation, wind, and precipitation. Objective. To evaluate two types of anti-insect screens in the ventilation areas of a naturally ventilated Colombian greenhouse in order to analyze the effect on the ventilation rates and the generated microclimate. Materials and methods. The study was carried out in 2019 in the department of Magdalena, Colombia. The methodological approach included the use of a 2-D computational fluid model (CFD) for the development of fifteen steady-state simulations. The CFD model was experimentally validated in the prototype of the real greenhouse evaluated. Results. Goodness-of-fit parameters between measured and simulated data showed absolute mean error (MAE) and root mean squared error (RMSE) values for temperature and relative humidity of 0.15 and 0.32 °C, 2.41 and 2.73 %, respectively. There was an average reduction in ventilation rates between 55.3 and 77.1 % compared to the reference scenario that did not include the presence of anti-insect screens, this reduction generated modifications in the behavior of the temperature and relative humidity variables inside the greenhouse, with a marked heterogeneous spatial distribution. Conclusion. The most inadequate microclimatic conditions occurred in scenarios of low external wind speed; therefore, it is recommended to select and implement some type of anti-insect screen in the ventilation areas of a greenhouse based on the local behavior of this variable.

Introduction.In Colombia, horticultural production in the low tropics is limited mainly by biotic factors such as pest attacks, pathogens, and abiotic factors such as extreme values of temperature, solar radiation, wind, and precipitation.Objective.To evaluate two types of anti-insect screens in the ventilation areas of a naturally ventilated Colombian greenhouse in order to analyze the effect on the ventilation rates and the generated microclimate.Materials and methods.The study was carried out in 2019 in the department of Magdalena, Colombia. The methodological approach included the use of a 2-D computational fluid model (CFD) for the development of fifteen steady-state simulations. The CFD model was experimentally validated in the prototype of the real greenhouse evaluated.Results.Goodness-of-fit parameters between measured and simulated data showed absolute mean error (MAE) and root mean squared error (RMSE) values for temperature and relative humidity of 0.15 and 0.32 °C, 2.41 and 2.73 %, respectively. There was an average reduction in ventilation rates between 55.3 and 77.1 % compared to the reference scenario that did not include the presence of anti-insect screens, this reduction generated modifications in the behavior of the temperature and relative humidity variables inside the greenhouse, with a marked heterogeneous spatial distribution.Conclusion.The most inadequate microclimatic conditions occurred in scenarios of low external wind speed; therefore, it is recommended to select and implement some type of anti-insect screen in the ventilation areas of a greenhouse based on the local behavior of this variable. Introducción.En Colombia, la producción hortícola en el trópico bajo es limitada principalmente por factores bióticos como el ataque de plagas, patógenos y factores abióticos como valores extremos de temperatura, radiación solar, viento y precipitación.Objetivo.Evaluar dos tipos de mallas anti-insecto en las áreas de ventilación de un invernadero colombiano ventilado de formado natural con el fin de analizar el efecto sobre las tasas de ventilación y el microclima generado.Materiales y métodos.El Estudio se desarrolló en el año 2019 en el departamento de Magdalena, Colombia. El enfoque metodológico incluyó el uso de modelo computacional de fluidos (CFD) 2-D para el desarrollo de quince simulaciones en estado estacionario, el modelo CFD fue validado experimentalmente en el prototipo del invernadero real evaluado.Resultados.Los parámetros de bondad de ajuste entre los datos medidos y simulados mostraron valores de error medio absoluto (MAE) y la raíz del error cuadrático medio (RMSE) para la temperatura y la humedad relativa de 0,15 y 0,32 °C, 2,41 y 2,73 %, respectivamente. Hubo una reducción promedio de las tasas de ventilación entre 55,3 y 77,1 % en comparación con el escenario de referencia que no incluyó la presencia de mallas anti-insecto, esta reducción generó modificaciones en el comportamiento de las variables temperatura y humedad relativa en el interior del invernadero, con una marcada distribución espacial heterogénea.Conclusión.Las condiciones micro climáticas más inadecuadas se presentaron en escenarios de baja velocidad de viento exterior, por lo tanto, es recomendable seleccionar e implementar algún tipo de malla anti-insecto en las áreas de ventilación de un invernadero basado en el comportamiento local de esta variable.

This theoretical and applied research analyses the microclimate of Chamberí Square in Madrid, a city with an intense Urban Heat Island effect. Contact temperature of finishing materials of facades, pavements, and urban furniture were measured. Dry air temperature, relative humidity, wind velocity and direction were measured too, both in the sun and in the shade. Shading and solar radiation simulations were carried out by constructing a 3D model defining finishing materials’ properties, vegetation, and existing trees. Public space users were also located, and their activities registered. The obtained data wascompared to a traditional bioclimatic study. It is concluded that these studies are effective to design comfortable urban spaces because they are useful in order to create alternative microclimates. Field measurements reveal essential sun radiation and shading studies in urban design for a proper selection and location of materials with a variety of thermal properties and for the correct use of natural soils, vegetation, and water. The comfort strategies defined by traditional bioclimatic tools and the real use of urban space do not come together. Noticeable differences between historical climate data, estate weatherstation, and local measurements are detected. The Urban Heat Island of the square is numerically defined. Este trabajo de investigación se centra en el estudio teórico y experimental del microclima urbano de la plaza Chamberí de Madrid, ciudad con una marcada Isla de Calor. Para ello, se realizaron mediciones in-situ de temperatura superficial de materiales en fachadas, pavimentos y mobiliario urbano, de temperatura seca, humedad relativa del aire y de velocidad y dirección del viento en condiciones de soleamiento y sombreamiento. Se levantó el entorno, la vegetación, arbolado y materiales de acabado en 3D para desarrollar simulaciones de soleamiento y radiación solar. Paralelamente, se registró el uso que las personas hacían del espacio urbano. Finalmente se compararon los resultados con un estudio bioclimático tradicional que serviría para definir el confort. Se concluyó que las herramientas bioclimáticas son efectivas para el diseño de espacios confortables térmicamente, siempre y cuando se creen microclimas alternativos que den opción de adaptarse al entorno. Las mediciones de campo revelan la importancia de las propiedades térmicas de los materiales y la necesidad de realizar estudios de soleamiento para la selección y localización de materiales con diversas propiedades higrotérmicas y el correcto empleo de suelos naturales, vegetación y agua. Se observa que las estrategias teóricas para alcanzar el confort definidas mediante las herramientas tradicionales, en numerosasocasiones, no coincide con el uso real del espacio público. Además, se detectaron notables diferencias entre los datos climáticos históricos, los de la estación meteorológica estatal más cercana y las mediciones locales. Se detecta numéricamente el efecto de Isla de Calor Urbana en la plaza, respecto al parque del Retiro.

Introduction. Precipitation, temperature, radiation, and relative humidity vary according to height, this causes the presence of microclimates that affect the productivity of the animals. Objective. Associate the climatic conditions present in the productive systems with dairy production of a pure Jersey herd in two altitudinal floors of the province of Cartago, Costa Rica. Materials and methods. In retrospect, during the year 2016, the productive information of two dairy farms, located at 660 and 1800 m.a.s.l. was evaluated. From the first farm, the records of 61 animals in a twelve-year period (12,083 data) were analyzed; while in the second, the lactations of 387 animals in a five-year period (13,820 records) were analyzed. Observations included: identification of the cow, day of generation of the record, month, year, daily milk production, lactation days, calving number, animal age, temperature, precipitation, solar radiation and average relative humidity. Results. The lactation days, the lactation number (3-5), the age of the animal (3.7 to 5.8 years), and the calving number affected the daily milk production on both farms (p

The structure of dung beetle communities inhabiting tropical forests are known to be sensitive to many kinds of environmental changes such as microclimate related to vegetation structure. I examined Scarabaeinae assemblages in two sites of undisturbed high forest and two sites of low forest forming a transitional zone with the open habitat of an inselberg in French Guiana. Sampling was made with pitfall and flight interception traps during 2003 and 2004. The driest and warmest conditions characterized the low forest sites. Across two years we obtained 2 927 individuals from 61 species with pitfall traps and 1 431 individuals from 85 species with flight interception traps. Greater species richness and abundance characterized all sites sampled with pitfall traps during 2003 more than 2004. In 2003 no differences were detected among sites by rarefaction analyses. In 2004 the species richest high forest site was significantly different from one of the low forest sites. For both years Clench model asymptotes for species richness were greater in high forest than in low forest sites. For both years, mean per-trap species richness, abundance and biomass among high forest sites were similar and higher than in low forest sites, especially where the lowest humidity and the highest temperature were recorded. Within the two low forest sites, species richness and abundance recorded during the second year, decreased with distance to edge. Different dominant roller species characterized the pitfall samples in one site of low forest and in other sites. Small variations in microclimatic conditions correlated to canopy height and openness likely affected dung beetle assemblages but soil depth and the presence of large mammals providing dung resource may also play a significant role. Es conocido que la estructura de las comunidades de escarabajos coprófagos que habitan los bosques tropicales es sensible a diferentes tipos de cambios ambientales tales como el microclima asociado a la vegetación. Hemos examinado las comunidades de Scarabaeinae en dos parcelas de bosque alto sin perturbación y en dos parcelas de bosque bajo, presentes en la transición con el hábitat abierto de un inselberg en la Guayana francesa. Las parcelas de bosque bajo tienen condiciones climáticas más cálidas y secas. A lo largo de dos años, mediante trampas de caída con atrayente, capturamos un total 2 927 individuos de 61 especies y con trampas de intercesión de vuelo, un total de 1 431 individuos pertenecientes a 85 especies. Una mayor riqueza específica y abundancia caracteriza a todos los sitios de muestreo con trampas de caída en 2003 más que en 2004. En el 2003 no se detectaron diferencias entre los sitios de análisis de rarefacción. En el 2004 la riqueza de especies fue significativamente diferente en el bosque de altura que en el bajo. Durante los dos años, las asíntotas del modelo de Clench para la riqueza específica fueron mayores en bosque alto que en bosque bajo. Durante los dos años, el promedio por trampa de riqueza específica, abundancia y biomasa fueron similares entre las parcelas de bosque alto, pero mayores que en las parcelas de bosque bajo, especialmenteen los sitios en los que se registró una mayor temperatura y menor humedad. Dentro de las dos parcelas de bosque bajo, la riqueza específica y la abundancia durante el segundo año disminuyeron con la distancia al borde. Las especies de coprófagos rodador que dominaban una de las parcelas del bosque bajo eran distintas de la del resto de parcelas. Los resultados de este estudio muestran que las pequeñas variaciones en las condiciones microclimáticas que están correlacionadas con la altura y la apertura del dosel arbóreo probablemente afectan a las comunidades de escarabajos coprófagos, aunque también son importantes la presencia de un suelo profundo y de grandes mamíferos que proporcionan recursos con sus heces.

Se caracterizaron tres tipos de borde de bosque altoandino: borde de Chusquea scandens, paramizado y antiguo; este último denominado así por presentar un estado sucesional más avanzado. Se seleccionaron dos parches de bosque por cada tipo de borde, para analizar 13 criterios entre fisiográficos, microclimáticos, estructura y composición de la vegetación. Tres de los criterios (pendiente, forma y área del parche) son poco determinantes del tipo de hábitat de borde, los demás están estrechamente relacionados con las condiciones del microambiente y éste a su vez con la estructura y composición de la vegetación, confiriendo características particulares a cada hábitat de borde. El borde paramizado muestra la menor capacidad de autorregulación ambiental estando más expuesto a la fluctuación en estas variables, debido a su exposición directa a la acción del viento y a la pérdida de los estratos arbóreos más altos (entre 10 y 15 m), por lo que requiere la mayor intervención para su restauración. El borde de chusque es el más resguardado al actuar esta especie como una barrera protectora, que sin embargo debe ser controlada para promover la expansión del bosque como habita en el borde antiguo, el cual presenta una capacidad reguladora intermedia entre los otros dos. Characterization of High Andean forest edges and implications for their ecological restoration (Colombia). The growth of a forest patch through colonization of the adjacent matrix is mostly determined by the particular characteristics of the edge zone. Knowing how these characteristics are related to a specific edge type and how they influence the regeneration process, is important for High Andean forest edges restoration. This study aimed to characterize three types of High Andean forest edge in Cogua Forest Reserve (Colombia): 1) edge of Chusquea scandens, 2) "paramizado", and 3) old edge, characterized for being in a later successional state. Two forest patches were chosen for each edge type and 13 criteria were analyzed; these were of topographic order, micro-environmental order, vegetation structure and species composition. in each patch the vegetation was evaluated by means of two 60 m transects perpendicular to the edge and along the matrix-edgeinterior of the forest gradient. All woody plant species were identified and counted to determine their abundance. Environmental variables (air temperature, relative humidity, wind speed, and light radiation) were measured in one of the transects. Three of the 13 criteria were of little importance in shaping the type of edge habitat (slope, patch shape and area). The others were closely related with the micro-environmental conditions and in turn with the vegetation structure and composition; this relationship confers particular characteristics to each edge type. The microclimate and floristic edge limits coincided; edges extend between 10 and 20 m into the forest depending on the edge type. The paramizado edge has the smallest environmental self-regulation capacity and is more exposed to fluctuations of the studied variables, because of its greatest exposition to the wind action and loss of the tallest trees (between 10 and 15 m) which regulate the understorey microclimate. This low environmental buffer capacity prevents the establishing of mature forest species (for example, Schefflera sp. and Oreopanax bogotensis) although they are found in other areas within the same patch. All these results show that the paramizado edge needs the most intervention for its restoration. The Chusquea scandens edge forest is the most sheltered since this species acts as a protecting shield. However it still needs to be controlled to allow the adjacent matrix colonization by the forest species and natural regeneration, as it does in the old edge type forest, which moreover has an intermediate self-regulating capacity relative to the other two. The vegetation composition reveals that most of the edge species can also grow inside, beyond the forest edge. Rev. Biol. Trop. 56 (3): 1543-1556. Epub 2008 September 30.

Characterization of High Andean forest edges and implications for their ecological restoration (Colombia). The growth of a forest patch through colonization of the adjacent matrix is mostly determined by the particular characteristics of the edge zone. Knowing how these characteristics are related to a specific edge type and how they influence the regeneration process, is important for High Andean forest edges restoration. This study aimed to characterize three types of High Andean forest edge in Cogua Forest Reserve (Colombia): 1) edge of Chusquea scandens, 2) "paramizado", and 3) old edge, characterized for being in a later succes- sional state. Two forest patches were chosen for each edge type and 13 criteria were analyzed; these were of topographic order, micro-environmental order, vegetation structure and species composition. in each patch the vegetation was evaluated by means of two 60 m transects perpendicular to the edge and along the matrix-edge- interior of the forest gradient. All woody plant species were identified and counted to determine their abundance. Environmental variables (air temperature, relative humidity, wind speed, and light radiation) were measured in one of the transects. Three of the 13 criteria were of little importance in shaping the type of edge habitat (slope, patch shape and area). The others were closely related with the micro-environmental conditions and in turn with the vegetation structure and composition; this relationship confers particular characteristics to each edge type. The microclimate and floristic edge limits coincided; edges extend between 10 and 20 m into the forest depending on the edge type. The paramizado edge has the smallest environmental self-regulation capac- ity and is more exposed to fluctuations of the studied variables, because of its greatest exposition to the wind action and loss of the tallest trees (between 10 and 15 m) which regulate the understorey microclimate. This low environmental buffer capacity prevents the establishing of mature forest species (for example, Schefflera sp. and Oreopanax bogotensis) although they are found in other areas within the same patch. All these results show that the paramizado edge needs the most intervention for its restoration. The Chusquea scandens edge forest is the most sheltered since this species acts as a protecting shield. However it still needs to be controlled to allow the adjacent matrix colonization by the forest species and natural regeneration, as it does in the old edge type forest, which moreover has an intermediate self-regulating capacity relative to the other two. The vegetation composi- tion reveals that most of the edge species can also grow inside, beyond the forest edge. Rev. Biol. Trop. 56 (3): 1543-1556. Epub 2008 September 30.