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Urban areas present thermal environments that may be challenging for altricial nestlings, particularly in early development. We aimed to evaluate whether altricial Bewick's Wren (Thryomanes bewickii) nestlings experienced thermal stress in the nest-box during the early- and late-developmental stages. We determined the thermoregulatory set point (thermoneutral range) of nestlings by measuring cloacal body temperature of five nestlings from three nests, every other day from hatching until they fledged. We also exposed nestlings to a thermal challenge from day 5 to determine the age of endothermy. We used dataloggers to determine the thermal environment inside and outside of three nest-boxes, and obtained the operative temperature for nestlings in the nest-box using 3D-printed models corresponding to early- and late-developmental stages. Ambient temperatures inside the nest box fluctuated throughout the day, being colder at night just before daybreak (min range: 10.4°C - 10.8°C), and hotter in the afternoon (max range: 25.8°C - 28.3°C). However, temperatures in the nest-box did not reach the extreme high and low outside temperatures, and were warmer at night. Nestlings reached age of endothermy at 9 ± 2.3 days after hatching, and showed a thermoneutral range of body temperature above ambient temperatures in the nest-box. Operative temperatures of models in the nest-box closely followed ambient temperatures, and were below nestlings' thermoneutral range. Therefore, nestlings could experience thermal stress when parents do not provide additional buffering while off the nest for foraging. Although nest-boxes provide limited thermal benefits for nesting birds in tropical cities, they still provide valuable nesting and roosting sites where natural cavities are limited in availability. [ABSTRACT FROM AUTHOR]

The Urban Heat Island (UHI), caused by the increase in impermeable surfaces, high urban density, and lack of shade, is a common phenomenon that could end intensified by climate changes, especially in warmhumid climates. This research evaluated the use of urban arborization as a mitigation strategy for the heat island effect in the public spaces of Barranquilla, Colombia. The “Carrera 44” avenue was selected as the study area due to its high solar radiation exposure. Computational simulations were performed to assess the operative temperature with different options for tree shadow in 2020 and 2050. The results display the percentage of UHI mitigation for each proposed situation. It is estimated that the findings from this study can serve as guidelines for designing public spaces in the Colombian Caribbean region.” [ABSTRACT FROM AUTHOR]

El ambiente térmico en una edificación influye en la salud, el bienestar y la productividad de las personas, así como en el consumo energético. La importancia del confort térmico en las edificaciones se reconoce desde hace décadas, no obstante, este aspecto es aún incipiente en la industria de la construcción colombiana, sobre todo en proyectos de vivienda. En esta investigación se analizó el desempeño térmico de tres tipos de vivienda comunes en la ciudad de Medellín. Para ello se calculó la temperatura operativa, el voto medio estimado (PMV) y el porcentaje estimado de insatisfechos (PPD), de acuerdo con la norma ISO 7730:2005. Los resultados mostraron que la inercia térmica de dos de los tres tipos de vivienda examinados no es suficiente para ofrecer un confort térmico adecuado, a pesar del clima templado del Valle de Aburrá. Estos resultados alertan sobre la vulnerabilidad de la población urbana en Colombia ante fluctuaciones extremas de temperatura.

The indoor thermal environment of buildings influences people's health, well-being and productivity, as well as energy consumption. The importance of thermal comfort in buildings has been recognized for decades. However, this aspect is still incipient in the Colombian construction industry, especially in housing projects. In this research, the thermal performance of three common housing types in the city of Medellin was analyzed. To do this, the operative temperature, the predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) were calculated in accordance with ISO 7730:2005. The results showed that the thermal inertia of two of the three types of housing examined was insufficient to offer adequate thermal conditions, despite the temperate climate of the Aburra Valley. These results warn about the vulnerability of urban population in Colombia to extreme temperature fluctuations. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Romanian Journal of Civil Engineering / Revista Română de Inginerie Civilă is the property of Matrix Rom and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We studied the thermal ecology of northern bobwhites (Colinus virginianus) to better understand the role of temperature in the field behavior of these birds. We obtained descriptive data on thermal aspects of the land-scape; bobwhite selection for Normalized Difference Vegetation Index (NDVI; vegetation biomass) classes and cover associations relative to their thermal properties; and thermal conditions at nests, mid-day coverts, and roosts. We collected data on a 796-ha area in the Texas Rolling Plains during May 2000-July 2003 using satellite imagery, black-bulb temperature probes, mortality- and temperature-sensing radio transmitters, and continuous-recording video cameras for nest observations. Linear models of black-bulb temperature (Tbb) as a function of air temperature (Ta) at a base weather station explained 42-70% of the variation in Tbb in 10 NDVI classes during daylight and 78% during night in summer (all NDVI classes; Jul 2001). During February 2002, Ta explained 38-92% of the variation during day and 89% of the variation at night. The linear models provided a means of qualitatively assessing thermal space on the landscape as Ta changed and of predicting Tbb in NDVI classes. At Ta = 42 °C, 100% of the 796-ha landscape under study had predicted Tbb > 39 °C, the approximate threshold leading to hyperthermia in bobwhites. Based on 9,287 radiolocations of 217 bobwhites, bobwhites selected for all NDVI classes in mixed-shrub cover (sand plum, [Prunus angustifolia]; fragrant sumac, [Rhus aromatica]) on an annual and seasonal basis. If Ta was <35 °C, the approximate upper critical temperature, the operative temperature (Te) experienced by bobwhites exceeded Ta in 699 of 818 simultaneous readings (n = 24 bobwhites with thermal transmitters) and the difference between Te and Ta increased as air temperature declined. Data from video cameras indicated thermal stress (i.e., gular flutter) in 25 of 26 incubating bobwhites. Gular flutter began at an average Ta of 30.4 ± 0.2 °C SE (n = 158) and total bouts of gular flutter averaged 87 minutes/bird/day after 16 June. Data from thermal radiotransmitters indicated 91.3 ± 6.1% of incubating adults were in thermal stress at Ta> 35 °C. Temperature of nest contents averaged about 30°C and incubating bobwhites appeared to protect nest contents more rigorously from hyperthermia than from hypothermia. Mid-day covert selection (NDVI 6, mixed-shrub cover; n = 58) during summer reduced bobwhite exposure to Tbb > 39 °C by an average of 1,600.7 heating-degree minutes in comparison with random points (n = 58) during 1200-1600 hours. The roosting disc appeared to confer energetic advantages at Ta < 16.2 °C and the advantage increased as Ta declined. Our results were consistent with the heat hypothesis on reproduction variability because we observed thermal stress at low Ta (≥22.1 °C) in incubating birds and we projected lethal Tbb, (53.2 °C) at high Ta (45 °C) in NDVI classes used by nesting bobwhites. Our results reaffirm that temperatures on the landscape are a legitimate concern for bobwhite managers. The goal of habitat management vis-à-vis temperature is to insure well-distributed mid-day coverts for thermal refugia in summer and ground cover of sufficient height and density to prevent heat excess in the near-ground environment. [ABSTRACT FROM AUTHOR]