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1.
J Exp Biol ; 227(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38958209

RESUMEN

As the world warms, it will be tempting to relate the biological responses of terrestrial animals to air temperature. But air temperature typically plays a lesser role in the heat exchange of those animals than does radiant heat. Under radiant load, animals can gain heat even when body surface temperature exceeds air temperature. However, animals can buffer the impacts of radiant heat exposure: burrows and other refuges may block solar radiant heat fully, but trees and agricultural shelters provide only partial relief. For animals that can do so effectively, evaporative cooling will be used to dissipate body heat. Evaporative cooling is dependent directly on the water vapour pressure difference between the body surface and immediate surroundings, but only indirectly on relative humidity. High relative humidity at high air temperature implies a high water vapour pressure, but evaporation into air with 100% relative humidity is not impossible. Evaporation is enhanced by wind, but the wind speed reported by meteorological services is not that experienced by animals; instead, the wind, air temperature, humidity and radiation experienced is that of the animal's microclimate. In this Commentary, we discuss how microclimate should be quantified to ensure accurate assessment of an animal's thermal environment. We propose that the microclimate metric of dry heat load to which the biological responses of animals should be related is black-globe temperature measured on or near the animal, and not air temperature. Finally, when analysing those responses, the metric of humidity should be water vapour pressure, not relative humidity.


Asunto(s)
Microclima , Animales , Calentamiento Global , Regulación de la Temperatura Corporal , Humedad , Temperatura
2.
Sci Rep ; 14(1): 16021, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992055

RESUMEN

Environmental conditions profoundly impact the health, welfare, and productivity of laying hens in commercial poultry farming. We investigated the association between microclimate variations, production indices, and histopathological responses to accidental Newcastle disease virus (NDV) infection within a controlled closed-house system. The study was conducted over seven months in a laying hen facility in Cairo, Egypt. Microclimate measurements included temperature, relative humidity (RH%), air velocity (AV), and the temperature humidity index (THI) that were obtained from specific locations on the front and back sides of the facility. Productivity indices, including the egg production percentage (EPP), egg weight (EW), average daily feed intake, and feed conversion ratio, were assessed monthly. During an NDV outbreak, humoral immune responses, gross pathology, and histopathological changes were evaluated. The results demonstrated significant (p < 0.05) variations in EPP and EW between the front and back sides except in April and May. AV had a significant (p = 0.006) positive effect (Beta = 0.346) on EW on the front side. On the back side, AV had a significant (p = 0.001) positive effect (Beta = 0.474) on EW, while it negatively influenced (p = 0.027) EPP (Beta = - 0.281). However, temperature, RH%, and THI had no impact and could not serve as predictors for EPP or EW on either farm side. The humoral immune response to NDV was consistent across microclimates, highlighting the resilience of hens. Histopathological examination revealed characteristic NDV-associated lesions, with no significant differences between the microclimates. This study underscores the significance of optimizing microclimate conditions to enhance laying performance by providing tailored environmental management strategies based on seasonal variations, ensuring consistent airflow, particularly near cooling pads and exhaust fans, and reinforcing the importance of biosecurity measures under field challenges with continuous monitoring and adjustment.


Asunto(s)
Pollos , Enfermedad de Newcastle , Virus de la Enfermedad de Newcastle , Enfermedades de las Aves de Corral , Animales , Enfermedad de Newcastle/virología , Pollos/virología , Femenino , Virus de la Enfermedad de Newcastle/fisiología , Enfermedades de las Aves de Corral/virología , Egipto , Microclima , Temperatura
3.
PLoS One ; 19(6): e0302025, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843173

RESUMEN

In dengue-endemic areas, transmission control is limited by the difficulty of achieving sufficient coverage and sustainability of interventions. To maximize the effectiveness of interventions, areas with higher transmission could be identified and prioritized. The aim was to identify burden clusters of Dengue virus (DENV) infection and evaluate their association with microclimatic factors in two endemic towns from southern Mexico. Information from a prospective population cohort study (2·5 years of follow-up) was used, microclimatic variables were calculated from satellite information, and a cross-sectional design was conducted to evaluate the relationship between the outcome and microclimatic variables in the five surveys. Spatial clustering was observed in specific geographic areas at different periods. Both, land surface temperature (aPR 0·945; IC95% 0·895-0·996) and soil humidity (aPR 3·018; IC95% 1·013-8·994), were independently associated with DENV burden clusters. These findings can help health authorities design focused dengue surveillance and control activities in dengue endemic areas.


Asunto(s)
Virus del Dengue , Dengue , Microclima , Humanos , Dengue/epidemiología , Dengue/transmisión , México/epidemiología , Femenino , Masculino , Estudios Transversales , Adulto , Adolescente , Estudios Prospectivos , Niño , Enfermedades Endémicas , Adulto Joven , Persona de Mediana Edad , Preescolar , Humedad , Análisis por Conglomerados , Temperatura
4.
Sci Total Environ ; 941: 173572, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823707

RESUMEN

Forest canopy gaps can influence understorey microclimate and ecosystem functions such as decomposition. Gaps can arise from silviculture or tree mortality, increasingly influenced by climate change. However, to what degree canopy gaps affect the buffered microclimate in the understorey under macroclimatic changes is unclear. We, therefore, investigated the effect of forest gaps differing in structure and size (25 gaps: single tree gaps up to 0.67 ha cuttings) on microclimate and soil biological activity compared to closed forest in a European mixed floodplain forest. During the investigation period in the drought year 2022 between May and October, mean soil moisture and temperature as well as soil and air temperature fluctuations increased with increasing openness. In summer, the highest difference of monthly means between cuttings and closed forest in the topsoil was 3.98 ± 9.43 % volumetric moisture and 2.05 ± 0.89 °C temperature, and in the air at 30 cm height 0.61 ± 0.35 °C temperature. For buffering, both the over- and understorey tree layers appeared as relevant with a particularly strong influence of understorey density on soil temperature. Three experiments, investigating soil biological activity by quantifying decomposition rates of tea and wooden spatulas as well as mesofauna feeding activity with bait-lamina stripes, revealed no significant differences between gaps and closed forest. However, we found a positive significant effect of mean soil temperature on feeding activity throughout the season. Although soil moisture decreased during this period, it showed no counteracting effect on feeding activity. Generally, very few significant relationships were observed between microclimate and soil biological activity in single experiments. Despite the dry growing season, decomposition rates remained high, suggesting temperature had a stronger influence than soil moisture. We conclude that the microclimatic differences within the gap gradient of our experiment were not strong enough to affect soil biological activity considerably.


Asunto(s)
Cambio Climático , Bosques , Microclima , Suelo , Suelo/química , Temperatura , Árboles , Ecosistema , Estaciones del Año
5.
Reprod Fertil Dev ; 362024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38713807

RESUMEN

Context Seasonal microclimatic fluctuations can cause changes in sperm quality even in dairy bulls bred under temperate climate. These changes can vary between sires of different age and affect sperm freezability. Aims We aimed to evaluate the modulating effect of bull age and equilibration time before freezing on the seasonal pattern of sperm viability and DNA integrity post-thaw. Methods In the frame of systematic sperm quality control, we assessed the integrity of sperm plasma membrane and acrosome (PMAI) in 15,496 cryopreserved bovine batches, and the percentage of sperm with high DNA fragmentation index (%DFI) after 0h and 3h incubation at 38°C post-thaw (3h) in 3422 batches. Semen was equilibrated for 24h before freezing if collected on Monday or Wednesday and 72h if produced on Friday. We investigated the effect of season, bull age, equilibration, and temperature-humidity index (THI) on the day of semen collection on sperm traits using mixed-effects linear models. Key results PMAI and %DFI (0h and 3h) deteriorated with increasing THI. The effect of THI on %DFI was detected with a 30-day time lag. Seasonal fluctuations of sperm quality were similar between young, mature, and older sires. Prolonged equilibration did not affect PMAI but was linked to elevated %DFI (3h) in summer. Conclusions Extending equilibration from 24 to 72h is compatible with commercial standards of bovine sperm quality post-thaw; however, it could interfere with the seasonal pattern of the latter. Implications Systematic monitoring of bovine sperm quality enables the prompt detection of stress factors related to microclimate and semen processing.


Asunto(s)
Criopreservación , Fragmentación del ADN , Estaciones del Año , Análisis de Semen , Preservación de Semen , Espermatozoides , Animales , Bovinos , Masculino , Criopreservación/veterinaria , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología , Análisis de Semen/veterinaria , Fragmentación del ADN/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Microclima , Factores de Edad , Motilidad Espermática/efectos de los fármacos
6.
Technol Health Care ; 32(S1): 487-499, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38759071

RESUMEN

BACKGROUND: Shoes upper has been shown to affect the shoe microclimate (temperature and humidity). However, the existing data on the correlation between the microclimate inside footwear and the body's physical factors is still quite limited. OBJECTIVE: This study examined whether shoes air permeability would influence foot microclimate and spatial characteristics of lower limb and body. METHODS: Twelve recreational male habitual runners were instructed to finish an 80 min experimental protocol, wearing two running shoes with different air permeability. RESULTS: Participants wearing CLOSED upper structure shoe exhibited higher in-shoe temperature and relative humidity. Although there was no significant difference, shank temperature and metabolism in OPEN upper structure shoes were lower. CONCLUSIONS: This indicates that the air permeability of shoes can modify the microclimate of the feet, potentially affecting the lower limb temperature. This study provides relevant information for the design and evaluation of footwear.


Asunto(s)
Humedad , Microclima , Carrera , Zapatos , Humanos , Masculino , Carrera/fisiología , Adulto , Adulto Joven , Temperatura , Pie/fisiología , Temperatura Corporal/fisiología , Diseño de Equipo
7.
J Environ Manage ; 360: 121128, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38776661

RESUMEN

Vegetation regulates microclimate stability through biophysical mechanisms such as evaporation, transpiration and shading. Therefore, thermal conditions in tree-dominated habitats will frequently differ significantly from standardized free-air temperature measurements. The ability of forests to buffer temperatures nominates them as potential sanctuaries for tree species intolerant to the increasingly challenging thermal conditions established by climate change. Although many factors influencing thermal conditions beneath the vegetation cover have been ascertained, the role of three-dimensional vegetation structure in regulating the understory microclimate remains understudied. Recent advances in remote sensing technologies, such as terrestrial laser scanning, have allowed scientists to capture the three-dimensional structural heterogeneity of vegetation with a high level of accuracy. Here, we examined the relationships between vegetation structure parametrized from voxelized laser scanning point clouds, air and soil temperature ranges, as well as offsets between field-measured temperatures and gridded free-air temperature estimates in 17 sites in a tropical mountain ecosystem in Southeast Kenya. Structural diversity generally exerted a cooling effect on understory temperatures, but vertical diversity and stratification explained more variation in the understory air and soil temperature ranges (30%-40%) than canopy cover (27%), plant area index (24%) and average stand height (23%). We also observed that the combined effects of stratification, canopy cover and elevation explained more than half of the variation (53%) in understory air temperature ranges. Stratification's attenuating effect was consistent across different levels of elevation. Temperature offsets between field measurements and free-air estimates were predominantly controlled by elevation, but stratification and structural diversity were influential predictors of maximum and median temperature offsets. Moreover, stable understory temperatures were strongly associated with a large offset in daytime maximum temperatures, suggesting that structural diversity primarily contributes to thermal stability by cooling daytime maximum temperatures. Our findings shed light on the thermal influence of vertical vegetation structure and, in the context of tropical land-use change, suggest that decision-makers aiming to mitigate the thermal impacts of land conversion should prioritize management practices that preserve structural diversity by retaining uneven-aged trees and mixing plant species of varying sizes, e.g., silvopastoral, or agroforestry systems.


Asunto(s)
Cambio Climático , Ecosistema , Microclima , Clima Tropical , Árboles , Humanos , Temperatura , Bosques , Biodiversidad , Kenia
8.
Int J Biometeorol ; 68(7): 1315-1326, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705900

RESUMEN

Winter cold wave adaptation strategies in hot climates due to climate change didn't receive the deserved attention from previous studies. Therefore, this study comprehensively investigates the impact of various windbreak parameters on mitigating winter cold stress in hot steppe-arid climate. A microclimate model for a residential campus was built and validated through on-site measurement on a typical winter day to assess thirty-two scenarios for tree characteristics and spatial configuration windbreak parameters based on PET, wind speed, and Air Temperature (AT). Moreover, four configurations, that had best results on mitigating cold stress in winter, were tested during typical summer conditions to couple the assessment of cold and hot seasons. Additionally, environmental analysis for all scenarios was conducted. The results revealed that the most effective parameters for mitigating cold stress are tree distribution, Leaf Area Density (LAD), row number, spacing, and shape. Double rows of high LAD and medium height trees with small spacing yielded the best cold stress mitigation effect. Furthermore, the windbreak reduced the cold stress in the morning and night by 19.31% and 18.06%, respectively. It reduced AT and wind speed at night by 0.79 °C and 2.56 m/s, respectively. During summer, very hot PET area was reduced by 21.79% and 19.5% at 12:00 and 15:00, respectively.


Asunto(s)
Cambio Climático , Microclima , Modelos Teóricos , Estaciones del Año , Árboles , Viento , Frío
9.
Biosens Bioelectron ; 259: 116379, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38749288

RESUMEN

The emerging wearable plant sensors demonstrate the capability of in-situ measurement of physiological and micro-environmental information of plants. However, the stretchability and breathability of current wearable plant sensors are restricted mainly due to their 2D planar structures, which interfere with plant growth and development. Here, origami-inspired 3D wearable sensors have been developed for plant growth and microclimate monitoring. Unlike 2D counterparts, the 3D sensors demonstrate theoretically infinitely high stretchability and breathability derived from the structure rather than the material. They are adjusted to 100% and 111.55 mg cm-2·h-1 in the optimized design. In addition to stretchability and breathability, the structural parameters are also used to control the strain distribution of the 3D sensors to enhance sensitivity and minimize interference. After integrating with corresponding sensing materials, electrodes, data acquisition and transmission circuits, and a mobile App, a miniaturized sensing system is produced with the capability of in-situ and online monitoring of plant elongation and microclimate. As a demonstration, the 3D sensors are worn on pumpkin leaves, which can accurately monitor the leaf elongation and microclimate with negligible hindrance to plant growth. Finally, the effects of the microclimate on the plant growth is resolved by analyzing the monitored data. This study would significantly promote the development of wearable plant sensors and their applications in the fields of plant phenomics, plant-environment interface, and smart agriculture.


Asunto(s)
Técnicas Biosensibles , Microclima , Desarrollo de la Planta , Dispositivos Electrónicos Vestibles , Técnicas Biosensibles/instrumentación , Humanos , Diseño de Equipo , Hojas de la Planta/química , Cucurbita/crecimiento & desarrollo
10.
Ecology ; 105(6): e4313, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38708902

RESUMEN

Increased temperatures associated with urbanization (the "urban heat island" effect) have been shown to impact a wide range of traits across diverse taxa. At the same time, climatic conditions vary at fine spatial scales within habitats due to factors including shade from shrubs, trees, and built structures. Patches of shade may function as microclimate refugia that allow species to occur in habitats where high temperatures and/or exposure to ultraviolet radiation would otherwise be prohibitive. However, the importance of shaded microhabitats for interactions between species across urbanized landscapes remains poorly understood. Weedy plants and their foliar pathogens are a tractable system for studying how multiple scales of climatic variation influence infection prevalence. Powdery mildew pathogens are particularly well suited to this work, as these fungi can be visibly diagnosed on leaf surfaces. We studied the effects of shaded microclimates on rates of powdery mildew infection on Plantago host species in (1) "pandemic pivot" surveys in which undergraduate students recorded shade and infection status of thousands of plants along road verges in urban and suburban residential neighborhoods, (2) monthly surveys of plant populations in 22 parks along an urbanization gradient, and (3) a manipulative field experiment directly testing the effects of shade on the growth and transmission of powdery mildew. Together, our field survey results show strong positive effects of shade on mildew infection in wild Plantago populations across urban, suburban, and rural habitats. Our experiment suggests that this relationship is causal, where microclimate conditions associated with shade promote pathogen growth. Overall, infection prevalence increased with urbanization despite a negative association between urbanization and tree cover at the landscape scale. These findings highlight the importance of taking microclimate heterogeneity into account when establishing links between macroclimate or land use context and prevalence of disease.


Asunto(s)
Microclima , Enfermedades de las Plantas , Urbanización , Enfermedades de las Plantas/microbiología , Ascomicetos/fisiología
11.
Mar Environ Res ; 198: 106523, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678752

RESUMEN

Climate change is altering environmental conditions, with microclimates providing small-scale refuges within otherwise challenging environments. Durvillaea (southern bull kelp; rimurapa) is a genus of large intertidal fucoid algae, and some species harbour diverse invertebrate communities in their holdfasts. We hypothesised that animal-excavated Durvillaea holdfasts provide a thermal refuge for epibiont species, and tested this hypothesis using the exemplar species D. poha. Using a southern Aotearoa New Zealand population as a case-study, we found extreme temperatures outside the holdfast were 4.4 °C higher in summer and 6.9 °C lower in winter than inside the holdfast. A microclimate model of the holdfasts was built and used to forecast microclimates under 2100 conditions. Temperatures are predicted to increase by 2-3 °C, which may exceed the tolerances of D. poha. However, if D. poha or a similar congeneric persists, temperatures inside holdfasts will remain less extreme than the external environment. The thermal tolerances of two Durvillaea-associated invertebrates, the trochid gastropod Cantharidus antipodum and the amphipod Parawaldeckia kidderi, were also assessed; C. antipodum, but not P. kidderi, displayed metabolic depression at temperatures above and below those inside holdfasts, suggesting that they would be vulnerable outside the holdfast and with future warming. Microclimates, such as those within D. poha holdfasts or holdfasts of similar species, will therefore be important refuges for the survival of species both at the northern (retreating edge) and southern (expanding edge) limits of their distributions.


Asunto(s)
Cambio Climático , Invertebrados , Kelp , Microclima , Animales , Kelp/fisiología , Nueva Zelanda , Invertebrados/fisiología , Temperatura , Anfípodos/fisiología
12.
Int J Biometeorol ; 68(7): 1437-1449, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38625431

RESUMEN

Camping has become a popular outdoor activity in China. However, the long and scorching summers in China's hot and humid regions pose challenges for campsites in maintaining thermal comfort. Therefore, we explored the impact of tree species and planting methods on the thermal comfort of urban campsites in hot and humid areas using the ENVI-met model to simulate the conditions of the study area. The reliability of the model was validated by comparing the simulated values of air temperature (Ta) and relative humidity (RH) with field measurements. We conducted an in-depth analysis of common trees in hot and humid areas and analyzed the effects of five tree species and four tree planting forms on the microclimate of campsites in such areas, using the physiological equivalent temperature (PET) as the evaluation index of thermal comfort. The results indicated that: (1) trees with larger crown widths were most effective in improving outdoor thermal comfort. The ability of trees to regulate microclimate was more influenced by crown width than by leaf area index (LAI), and (2) trees planted in patches provided the highest level of thermal comfort, whereas single trees provided the lowest. However, relying solely on tree planting made it difficult to significantly reduce outdoor heat stress. Therefore, other methods such as increasing ventilation or mist spray should be adopted to modify camping area. This study provides a reference for the planting design of outdoor campsites in hot and humid regions of China.


Asunto(s)
Calor , Humedad , Microclima , Árboles , China , Árboles/crecimiento & desarrollo , Acampada , Sensación Térmica , Modelos Teóricos , Temperatura
13.
BMC Plant Biol ; 24(1): 258, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594637

RESUMEN

BACKGROUND: Weed control is essential for agricultural floor management in vineyards and the inter-row mulching is an eco-friendly practice to inhibit weed growth via filtering out photosynthetically active radiation. Besides weed suppression, inter-row mulching can influence grapevine growth and the accumulation of metabolites in grape berries. However, the complex interaction of multiple factors in the field challenges the understanding of molecular mechanisms on the regulated metabolites. In the current study, black geotextile inter-row mulch (M) was applied for two vintages (2016-2017) from anthesis to harvest. Metabolomics and transcriptomics analysis were conducted in two vintages, aiming to provide insights into metabolic and molecular responses of Cabernet Sauvignon grapes to M in a semi-arid climate. RESULTS: Upregulation of genes related to photosynthesis and heat shock proteins confirmed that M weakened the total light exposure and grapes suffered heat stress, resulting in lower sugar-acid ratio at harvest. Key genes responsible for enhancements in phenylalanine, glutamine, ornithine, arginine, and C6 alcohol concentrations, and the downward trend in ε-viniferin, anthocyanins, flavonols, terpenes, and norisoprenoids in M grapes were identified. In addition, several modules significantly correlated with the metabolic biomarkers through weighted correlation network analysis, and the potential key transcription factors regulating the above metabolites including VviGATA11, VviHSFA6B, and VviWRKY03 were also identified. CONCLUSION: This study provides a valuable overview of metabolic and transcriptomic responses of M grapes in semi-arid climates, which could facilitate understanding the complex regulatory network of metabolites in response to microclimate changes.


Asunto(s)
Vitis , Vino , Vitis/metabolismo , Transcriptoma , Antocianinas/metabolismo , Microclima , Granjas , Frutas , Vino/análisis
14.
New Phytol ; 242(4): 1739-1752, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38581206

RESUMEN

The development of terrestrial ecosystems depends greatly on plant mutualists such as mycorrhizal fungi. The global retreat of glaciers exposes nutrient-poor substrates in extreme environments and provides a unique opportunity to study early successions of mycorrhizal fungi by assessing their dynamics and drivers. We combined environmental DNA metabarcoding and measurements of local conditions to assess the succession of mycorrhizal communities during soil development in 46 glacier forelands around the globe, testing whether dynamics and drivers differ between mycorrhizal types. Mycorrhizal fungi colonized deglaciated areas very quickly (< 10 yr), with arbuscular mycorrhizal fungi tending to become more diverse through time compared to ectomycorrhizal fungi. Both alpha- and beta-diversity of arbuscular mycorrhizal fungi were significantly related to time since glacier retreat and plant communities, while microclimate and primary productivity were more important for ectomycorrhizal fungi. The richness and composition of mycorrhizal communities were also significantly explained by soil chemistry, highlighting the importance of microhabitat for community dynamics. The acceleration of ice melt and the modifications of microclimate forecasted by climate change scenarios are expected to impact the diversity of mycorrhizal partners. These changes could alter the interactions underlying biotic colonization and belowground-aboveground linkages, with multifaceted impacts on soil development and associated ecological processes.


Asunto(s)
Biodiversidad , Cubierta de Hielo , Micorrizas , Micorrizas/fisiología , Cubierta de Hielo/microbiología , Suelo/química , Microclima , Microbiología del Suelo
15.
Environ Sci Pollut Res Int ; 31(19): 28594-28619, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38558347

RESUMEN

Appropriate landscape configurations significantly mitigate rural thermal degradation. However, limited research exists on seasonal thermal comfort and the interconnections among landscape elements. Using ENVI-met software and field measurements, this study analyzed the microclimate of Dayuwan Village Square in Wuhan City. Fifteen design scenarios, including tree planting, building greening, albedo adjustment, and expanded tree coverage, were quantitatively evaluated to assess their impact on outdoor thermal comfort. Additionally, synergistic interactions between mitigation strategies were explored. The study found that increasing evergreen tree coverage by 50% has minimal impact on comfort during winter and spring. However, it significantly reduces temperatures in summer and autumn, resulting in average predicted mean vote (PMV) decreases of 0.315 and 0.643, respectively. Additionally, this strategy optimizes PMV values at 18:00 on extreme days, with a 0.102 decrease in summer and a 0.002 increase in winter. This research offers practical and sustainable guidance to designers for enhancing mitigation effects through optimal landscape configuration, providing a technical framework for rural environmental improvements.


Asunto(s)
Estaciones del Año , China , Temperatura , Ciudades , Árboles , Microclima
16.
Environ Sci Pollut Res Int ; 31(20): 29048-29070, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38568310

RESUMEN

Rapid urbanisation has led to significant environmental and climatic changes worldwide, especially in urban heat islands where increased land surface temperature (LST) poses a major challenge to sustainable urban living. In the city of Abha in southwestern Saudi Arabia, a region experiencing rapid urban growth, the impact of such expansion on LST and the resulting microclimatic changes are still poorly understood. This study aims to explore the dynamics of urban sprawl and its direct impact on LST to provide important insights for urban planning and climate change mitigation strategies. Using the random forest (RF) algorithm optimised for land use and land cover (LULC) mapping, LULC models were derived that had an overall accuracy of 87.70%, 86.27% and 93.53% for 1990, 2000 and 2020, respectively. The mono-window algorithm facilitated the derivation of LST, while Markovian transition matrices and spatial linear regression models assessed LULC dynamics and LST trends. Notably, built-up areas grew from 69.40 km2 in 1990 to 338.74 km2 in 2020, while LST in urban areas showed a pronounced warming trend, with temperatures increasing from an average of 43.71 °C in 1990 to 50.46 °C in 2020. Six landscape fragmentation indices were then calculated for urban areas over three decades. The results show that the Largest Patch Index (LPI) increases from 22.78 in 1990 to 65.24 in 2020, and the number of patches (NP) escalates from 2,531 in 1990 to an impressive 10,710 in 2020. Further regression analyses highlighted the morphological changes in the cities and attributed almost 97% of the LST variability to these urban patch dynamics. In addition, water bodies showed a cooling trend with a temperature decrease from 33.76 °C in 2000 to 29.69 °C in 2020, suggesting an anthropogenic influence. The conclusion emphasises the urgent need for sustainable urban planning to counteract the warming trends associated with urban sprawl and promote climate resilience.


Asunto(s)
Planificación de Ciudades , Cambio Climático , Microclima , Temperatura , Urbanización , Arabia Saudita , Ciudades
17.
J Comp Physiol B ; 194(2): 203-212, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38587619

RESUMEN

Winter energy stores are finite and factors influencing patterns of activity are important for overwintering energetics and survival. Hibernation patterns (e.g., torpor bout duration and arousal frequency) often depend on microclimate, with more stable hibernacula associated with greater energy savings than less stable hibernacula. We monitored hibernation patterns of individual big brown bats (Eptesicus fuscus; Palisot de Beauvois, 1796) overwintering in rock-crevices that are smaller, drier, and less thermally stable than most known cave hibernacula. While such conditions would be predicted to increase arousal frequency in many hibernators, we did not find support for this. We found that bats were insensitive to changes in hibernacula microclimate (temperature and humidity) while torpid. We also found that the probability of arousal from torpor remained under circadian influence, likely because throughout the winter during arousals, bats commonly exit their hibernacula. We calculated that individuals spend most of their energy on maintaining a torpid body temperature a few degrees above the range of ambient temperatures during steady-state torpor, rather than during arousals as is typical of other small mammalian hibernators. Flight appears to be an important winter activity that may expedite the benefits of euthermic periods and allow for short, physiologically effective arousals. Overall, we found that big brown bats in rock crevices exhibit different hibernation patterns than conspecifics hibernating in buildings and caves.


Asunto(s)
Quirópteros , Hibernación , Animales , Quirópteros/fisiología , Hibernación/fisiología , Estaciones del Año , Conducta Animal/fisiología , Adaptación Fisiológica , Ritmo Circadiano/fisiología , Metabolismo Energético , Masculino , Temperatura Corporal , Femenino , Temperatura , Microclima , Humedad , Nivel de Alerta/fisiología , Letargo/fisiología
18.
PeerJ ; 12: e16986, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38685936

RESUMEN

Environmental heterogeneity poses a significant influence on the functional characteristics of species and communities at local scales. Environmental transition zones, such as at the savanna-forest borders, can act as regions of ecological tension when subjected to sharp variations in the microclimate. For ectothermic organisms, such as lizards, environmental temperatures directly influence physiological capabilities, and some species use different thermoregulation strategies that produce varied responses to local climatic conditions, which in turn affect species occurrence and community dynamics. In the context of global warming, these various strategies confer different types of vulnerability as well as risks of extinction. To assess the vulnerability of a species and understand the relationships between environmental variations, thermal tolerance of a species and community structure, lizard communities in forest-savanna transition areas of two national parks in the southwestern Amazon were sampled and their thermal functional traits were characterized. Then, we investigated how community structure and functional thermal variation were shaped by two environmental predictors (i.e., microclimates estimated locally and vegetation structure estimated from remote sensing). It was found that the community structure was more strongly predicted by the canopy surface reflectance values obtained via remote sensing than by microclimate variables. Environmental temperatures were not the most important factor affecting the occurrence of species, and the variations in ecothermal traits demonstrated a pattern within the taxonomic hierarchy at the family level. This pattern may indicate a tendency for evolutionary history to indirectly influence these functional features. Considering the estimates of the thermal tolerance range and warming tolerance, thermoconformer lizards are likely to be more vulnerable and at greater risk of extinction due to global warming than thermoregulators. The latter, more associated with open environments, seem to take advantage of their lower vulnerability and occur in both habitat types across the transition, potentially out-competing and further increasing the risk of extinction and vulnerability of forest-adapted thermoconformer lizards in these transitional areas.


Asunto(s)
Lagartos , Microclima , Bosque Lluvioso , Animales , Lagartos/fisiología , Pradera , Brasil , Calentamiento Global
19.
J Tissue Viability ; 33(2): 305-311, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553355

RESUMEN

OBJECTIVE: this study was undertaken to evaluate the efficacy of multilayer polyurethane foam with silicone (MPF) compared to transparent polyurethane film (TPF) dressings in the control of heel skin microclimate (temperature and moisture) of hospitalized patients undergoing elective surgeries. METHOD: the study took of a secondary analysis of a randomized self-controlled trial, involving patients undergoing elective surgical procedure of cardiac and gastrointestinal specialties in a university hospital in southern Brazil, from March 2019 to February 2020. Patients served as their own control, with their heels randomly allocated to either TPF (control) or MPF (intervention). Skin temperature was measured using a digital infrared thermometer; and moisture determined through capacitance, at the beginning and end of surgery. The study was registered in the Brazilian Registry of Clinical Trials: RBR-5GKNG5. RESULTS: significant difference in the microclimate variables were observed when the groups (intervention and control) and the timepoint of measurement (beginning and end of surgery) were compared. When assessing temperature, an increase (+3.3 °C) was observed with TPF and a decrease (-7.4 °C) was recorded with MPF. Regarding skin moisture, an increase in moisture (+14.6 AU) was recorded with TPF and a slight decrease (-0.3 AU) with MPF. CONCLUSIONS: The findings of this study suggest that MPF is more effective than TPF in controlling skin microclimate (temperature and moisture) in heels skin of hospitalized patients undergoing elective surgeries. However, this control should be better investigated in other studies.


Asunto(s)
Talón , Microclima , Humanos , Femenino , Masculino , Persona de Mediana Edad , Brasil , Anciano , Temperatura Cutánea/fisiología , Vendajes/normas , Vendajes/estadística & datos numéricos , Poliuretanos , Adulto
20.
Conserv Biol ; 38(4): e14246, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38445689

RESUMEN

Climate refugia, areas where climate is expected to remain relatively stable, can offer a near-term safe haven for species sensitive to warming temperatures and drought. Understanding the influence of temperature, moisture, and disturbance on sensitive species is critical during this time of rapid climate change. Coastal habitats can serve as important refugia. Many of these areas consist of working forestlands, and there is a growing recognition that conservation efforts worldwide must consider the habitat value of working lands, in addition to protected areas, to effectively manage large landscapes that support biodiversity. The sensitivity of forest bats to climate and habitat disturbance makes them a useful indicator taxon. We tested how microclimate and forest management influence habitat use for 13 species of insectivorous bats in a large climate refugium in a global biodiversity hotspot. We examined whether bat activity during the summer dry season is greater in forests where coastal fog provides moisture and more stable temperatures across both protected mature stands and those regularly logged. Acoustic monitoring was conducted at a landscape scale with 20 study sites, and generalized linear mixed models were used to examine the influence of habitat variables. Six species were positively associated with warmer nighttime temperature, and 5 species had a negative relationship with humidity or a positive relationship with climatic moisture deficit. Our results suggest that these mammals may have greater climate adaptive capacity than expected, and, for now, that habitat use may be more related to optimal foraging conditions than to avoidance of warming temperatures and drought. We also determined that 12 of the 13 regionally present bat species were regularly detected in commercial timberland stands. Because forest bats are highly mobile, forage over long distances, and frequently change roosts, the stewardship of working forests must be addressed to protect these species.


Influencia del microclima y el manejo forestal sobre especies de murciélagos ante el cambio global Resumen Los refugios climáticos, áreas en donde se espera que el clima permanezca relativamente estable, pueden ofrecer un santuario a corto plazo para las especies sensibles al aumento de temperaturas y la sequía. Es muy importante entender la influencia de la temperatura, la humedad y las perturbaciones sobre las especies sensibles durante estos tiempos de cambio climático repentino. Los hábitats costeros pueden funcionar como refugios importantes. Muchas de estas áreas consisten en bosques funcionales y cada vez hay más reconocimiento de que los esfuerzos mundiales de conservación deben considerar el valor del hábitat de los suelos funcionales, además de las áreas protegidas, para manejar de manera efectiva los extensos paisajes que mantienen a la biodiversidad. La sensibilidad de los murciélagos de los bosques ante las perturbaciones climáticas y de hábitat hace que sean un taxón indicador útil. Analizamos cómo los microclimas y el manejo forestal influyen sobre el uso de hábitat de 13 especies de murciélagos insectívoros en un refugio climático amplio dentro de un punto caliente de biodiversidad mundial. Examinamos si la actividad de los murciélagos durante la temporada seca de verano es mayor en los bosques en donde la niebla costera proporciona humedad y temperaturas más estables tanto en los árboles maduros como aquellos que son talados con regularidad. Realizamos el monitoreo acústico a escala de paisaje en 20 estudios de sitio y usamos modelos lineales mixtos generalizados para examinar la influencia de las variables del hábitat. Seis especies estuvieron asociadas positivamente con la temperatura nocturna más cálida y cinco especies tuvieron una relación negativa con la humedad o una relación positiva con el déficit climático de humedad. Nuestros resultados sugieren que estos mamíferos pueden tener una mayor capacidad de adaptación climática de lo que se pensaba y, por ahora, que el uso de hábitat puede estar más relacionado con las condiciones óptimas de forrajeo que con la evasión de las temperaturas elevadas y la sequía. También determinamos que 12 de las 13 especies con presencia regional fueron detectadas con regularidad en los puntos de tala comercial. Ya que los murciélagos del bosque tienden a moverse mucho, forrajear a lo largo de grandes distancias y con frecuencia cambiar de nido, debemos abordar la administración de los bosques funcionales para proteger a estas especies.


Asunto(s)
Quirópteros , Cambio Climático , Conservación de los Recursos Naturales , Agricultura Forestal , Bosques , Microclima , Animales , Quirópteros/fisiología , Conservación de los Recursos Naturales/métodos , Biodiversidad , Refugio de Fauna
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