RESUMO
The objective of this work was to evaluate the effect of using naturally shaded pastures on scrotal thermoregulatory capacity, testicular echotexture, and sperm morphology of Nelore (Bos indicus) and Canchim (5/8 Bos taurus x 3/8 Bos indicus) bulls in a tropical climate region. Sixty-four adult Nelore and Canchim bulls were used, equally allocated in Full Sun (FS, n = 32) or Crop-Livestock-Forestry (CLF, n = 32) pasture systems. During five consecutive climate seasons, the bulls underwent monthly breeding soundness evaluations and the biometeorological variables in the systems were continuously monitored. Microclimate was significantly different between systems. CLF system had lower BGHI than FS throughout the experimental period. No triple interaction (Season x Breed x Treatment, P > 0.05) was observed for any of the variables. Animals in CLF showed lower body temperature in Summer (FS:39.41 ± 0.05 vs. CLF:39.30 ± 0.05 °C; P = 0.005) and in Autumn (FS:39.54 ± 0.05 vs. CLF:39.35 ± 0.05 °C; P = 0.005). Access to shading did not determine differences in the evolution of scrotal biometry, temperatures, and scrotal thermal gradients (P > 0.05). Regardless of breed, animals in CLF showed greater right testicular volume (FS:247.5 ± 5.7 vs. CLF:259.0 ± 5.7 cm³; P < 0.05), more suitable parenchyma echotexture, and fewer microlithiasis spots in the Spring and Summer. Testosterone concentration was higher in FS (FS:2.6 ± 0.2 vs. CLF:2.1 ± 0.2 ng/mL; P = 0.035). Canchim bulls presented higher total sperm defects during the Autumn and Winter (P = 0.010), but the total defects levels for Canchim and Nelore bulls were in normal range for adult bulls. Thus, the natural shade in CLF system was effective in improving the microclimate of pastures and minimizing adverse environmental effects on some reproductive features of interest in beef cattle.
Assuntos
Regulação da Temperatura Corporal , Escroto , Espermatozoides , Testículo , Masculino , Animais , Testículo/anatomia & histologia , Testículo/fisiologia , Bovinos/fisiologia , Escroto/anatomia & histologia , Escroto/fisiologia , Espermatozoides/fisiologia , Microclima , Estações do Ano , Clima Tropical , Luz SolarRESUMO
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.
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Vírus da Dengue , Dengue , Microclima , Humanos , Dengue/epidemiologia , Dengue/transmissão , México/epidemiologia , Feminino , Masculino , Estudos Transversais , Adulto , Adolescente , Estudos Prospectivos , Criança , Doenças Endêmicas , Adulto Jovem , Pessoa de Meia-Idade , Pré-Escolar , Umidade , Análise por Conglomerados , TemperaturaRESUMO
Little has been studied about microclimate and the thermal comfort during the implementation of silvopastoral systems. This study aimed to evaluate the microclimate and thermal comfort during the implementation of High Biodiversity Silvopastoral System with Nuclei (SPSnu). Three treatments were investigated, SPSnu with 5 and 10% of the pasture area with nuclei, (SPSnu5 and SPSnu10, respectively), and treeless pasture (TLP). Each treatment was subdivided into 4 areas: within the nuclei, around the nuclei, around the nuclei with shade and internuclei. The analyzed variables were soil surface temperature, air temperature, wind speed, relative humidity, black globe temperature and the Heat Load Index (HLI) at 20 and 120 cm height. We hypothesized that the wind speed reduction associated with insufficient shade projection typical of the first years of SPSs may interfere in microclimate and thermal comfort during the hot seasons. SPSnu5 and SPSnu10 had a reduction in wind speed of 51.58% and 68.47% respectively when compared to TLP at 20 cm. Soil surface temperature and air temperature at 120 cm were higher for SPSnu than TLP. The same effect was observed for the HLI. At 20 cm, HLI indicated better thermal comfort in TLP than in the SPSnu treatments. The lack of shade projection from young nuclei in conjunction with the decrease of wind speed between the nuclei caused a higher air temperature and HLI in the SPSnu treatments, we called this conditions, windbreak countereffect. Farmers must knowledge this effect when implementing SPSs, and when necessary, mitigate with the proper management decisions.
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Microclima , Temperatura , Vento , Agricultura/métodos , Umidade , Solo , Sensação Térmica , BiodiversidadeRESUMO
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.
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Lagartos , Microclima , Floresta Úmida , Animais , Lagartos/fisiologia , Pradaria , Brasil , Aquecimento GlobalRESUMO
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.
Assuntos
Calcanhar , Microclima , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Brasil , Idoso , Temperatura Cutânea/fisiologia , Bandagens/normas , Bandagens/estatística & dados numéricos , Poliuretanos , AdultoRESUMO
This study aims to evaluate agreement among subjective thermal comfort, thermal sensation, thermal perception, and thermal tolerance indices, according to pedestrians in downtown Santa Maria, southern Brazil, which has a humid subtropical climate (Cfa). Between August 2015 and July 2016 (three periods), 1728 questionnaires were applied. Evaluation of the dependence of statistical variables was based on gender and age, at three periods of time: August 2015 (864 respondents), January 2016 (432 respondents), and July 2016 (432 respondents). Statistical evaluation was based on Pearson's chi-square test using RStudio software, and a significance level (α) of 5% for thermal comfort, thermal sensation, thermal preference, and thermal tolerance was used. Results indicated that age and gender affect the relationship between the variables. Thermal comfort and thermal tolerance presented the best correlation and coherence, regardless of age or gender. This study contributes to knowledge on the local microclimate and can contribute to urban planning to implement strategies that improve pedestrians' thermal comfort.
Assuntos
Pedestres , Humanos , Clima , Microclima , Sensação Térmica , Percepção , CidadesRESUMO
Although the abundance, survival, and pollination performance of honeybees are sensitive to changes in habitat and climate conditions, the processes by which these effects are transmitted to honey production and interact with beekeeping management are not completely understood. Climate change, habitat degradation, and beekeeping management affect honey yields, and may also interact among themselves resulting in indirect effects across spatial scales. We conducted a 2-year, multi-scale study on Chiloe Island (northern Patagonia), where we evaluated the most relevant environmental and management drivers of honey produced by stationary beekeepers. We found that the effects of microclimate, habitat, and management variables changed with the spatial scale. Among the environmental variables, minimum temperature, and cover of the invasive shrub, gorse (Ulex europaeus) had the strongest detrimental impacts on honey production at spatial scales finer than 4 km. Specialized beekeepers who adopted conventional beekeeping and had more mother colonies were more productive. Mean and minimum temperatures interacted with the percentage of mother colonies, urban cover, and beekeeping income. The gorse cover increased by the combination of high temperatures and the expansion of urban lands, while landscape attributes, such as Eucalyptus plantation cover, influenced beekeeping management. Results suggest that higher temperatures change the available forage or cause thermal stress to honeybees, while invasive shrubs are indicators of degraded habitats. Climate change and habitat degradation are two interrelated environmental phenomena whose effects on beekeeping can be mitigated through adaptive management and habitat restoration.
Assuntos
Mel , Abelhas , Animais , Mel/análise , Microclima , Criação de Abelhas/métodos , Ecossistema , PolinizaçãoRESUMO
This study aimed to assess the influence of the high biodiversity silvopastoral system (SPSnu) on the microclimate, pasture production, and pasture chemical composition. Microclimate variables and pasture production and chemical composition were measured in pared paddocks under SPSnu and treeless pasture (TLP) in a commercial farm during four seasons in Southern Brazil. SPSnu measurements were subdivided into two areas: around the nuclei (AN) and area inter-nuclei (IN). In the TLP paddocks, we plotted fictitious nuclei with the same areas and distributions of SPSnu, however without trees. For the microclimate measurements, these areas were noted when shaded or unshaded by the nuclei trees. In each season, the microclimate variables air temperature (AT, °C), relative humidity (RH, %), illuminance (Ilu, lux), wind speed (WS, m/s), and soil surface temperature (SST, °C) were measured. In addition, botanical composition (%), pasture production (kg/DM/ ha), and pasture chemical composition were evaluated. The SPSnu provided the lowest values of microclimate variables in all seasons (p < 0.05), except for the relative humidity. Winter had the highest thermal amplitude in the systems. The highest difference between SPSnu and TLP for AT (4.3 °C) and SST (5.2 °C) was measured during the hot seasons (spring and summer). In contrast, during cold seasons (autumn and winter) it observed highest thermal amplitude between SPSnu and TLP. Overall, the highest annual pasture production was observed in the SPSnu (p < 0.05). During the summer, the SPSnu areas showed the highest values of crude protein and dry matter (p < 0.05). During the winter, the TLP showed the lowest values (p < 0.05) of pasture production and dry matter. It was observed that SPSnu improved the microclimate at the pasture level, influencing pasture production and pasture chemical composition. The enhanced microclimate can partially mitigate some of the effects of climate change on pastoral agroecosystems, creating conditions for ecological rehabilitation of ecosystem processes and services. These conditions could be amplified to a biome level through a payment for ecosystem services program.
Assuntos
Ecossistema , Microclima , Temperatura , Temperatura Baixa , Árvores , Biodiversidade , Estações do Ano , UmidadeRESUMO
Climate temporality is a phenomenon that affects species activity and distribution patterns across spatial and temporal scales. Despite the global availability of microclimatic data, their use to predict activity patterns and distributions remains scarce, particularly at fine temporal scales (e.g. < month). Predicting activity patterns based on climatic data may allow us to foresee some of the consequences of climate change, particularly for ectothermic vertebrates. The Gila monster exhibits marked daily and seasonal activity patterns linked to physiology and reproduction. Here we evaluate whether ecological niche models fitted using microclimate data can predict temporal activity patterns using the Gila monster Heloderma suspectum as a study system. Furthermore, we identified whether the activity patterns are related to physiological constraints. We used dated occurrences from museum specimens and human observations to generate and test ecological niche models using minimum volume ellipsoids. We generated hourly microclimatic data for each occurrence site for 10 years using the NicheMapR package. For ecological niche modelling, we compared the traditional seasonal approach versus a daily activity pattern strategy for model construction. We tested both using the omission rate of independent observations (citizen science data). Finally, we tested whether unimodal and bimodal activity patterns for each season could be recreated through ecological niche modelling and whether these patterns followed known physiological constraints. The unimodal and bimodal activity patterns previously reported directly from tracking individuals across the year were recovered using niche modelling and microclimate across the species' geographical range. We found that upper thermal tolerances can explain the daily activity patterns of this species. We conclude that ecological niche models trained with microclimatic data can be used to predict activity patterns at high temporal resolutions, particularly on ectotherm species of arid zones coping with rapid climate modifications. Furthermore, the use of high temporal resolution variables can lead to a better niche delimitation, enhancing the results of any research objective that uses correlative models.
La estacionalidad climática es un fenómeno que afecta la actividad de las especies y los patrones de distribución a diferentes escalas espaciales y temporales. A pesar de la disponibilidad global de datos microclimáticos para estudiar dichos patrones, su uso sigue siendo escaso, particularmente en escalas temporales finas (e.g., < mes). La predicción de patrones de actividad basados en datos climáticos puede permitirnos prever algunas de las potenciales consecuencias del cambio climático, particularmente para los vertebrados ectotérmicos. El monstruo de Gila (Heloderma suspectum) exhibe marcados patrones de actividad diarios y estacionales vinculados a la fisiología y la reproducción. En este trabajo evaluamos cómo los modelos de nichos ecológicos ajustados con datos de microclima, pueden predecir patrones de actividad temporal, utilizando al monstruo de Gila como sistema de estudio. Además, identificamos si los patrones de actividad están relacionados con restricciones fisiológicas. Usamos registros de presencia provenientes de colecciones científicas y de ciencia ciudadana para generar y probar modelos de nichos ecológicos usando elipsoides de volumen mínimo. Generamos datos microclimáticos para cada hora en cada sitio de presencia durante diez años utilizando el paquete NicheMapR. Para el modelado de nichos ecológicos, comparamos el enfoque estacional tradicional con una estrategia de patrón de actividad diaria para la construcción del nicho. Ambos enfoques fueron probados utilizando la tasa de omisión de observaciones independientes (provenientes de datos de ciencia ciudadana). Finalmente, probamos si los patrones de actividad unimodales y bimodales para cada estación podían recrearse a través de modelos de nichos ecológicos y si estos patrones seguían restricciones fisiológicas conocidas. Los patrones de actividad unimodal y bimodal previamente informados directamente del seguimiento de individuos a lo largo del año, sí se recuperaron mediante el uso de modelos de nicho y microclimas en todo el rango geográfico de la especie. Encontramos también que las tolerancias térmicas superiores pueden explicar los patrones de actividad diaria de esta especie. Concluimos que los modelos de nichos ecológicos entrenados con datos microclimáticos pueden usarse para predecir patrones de actividad en altas resoluciones temporales, particularmente en especies ectotermas de zonas áridas que se enfrentan a modificaciones climáticas rápidas. Además, consideramos que el uso de variables con alta resolución temporal puede conducir a una mejor delimitación de nichos, mejorando los resultados de cualquier objetivo de investigación que utilice estos modelos correlativos.
Assuntos
Ecossistema , Microclima , Animais , Humanos , Vertebrados , Modelos Teóricos , GeografiaRESUMO
The edge effect, triggered by habitat fragmentation, alters forest microclimates and influences the life cycle of plants. Phenology may indicate the first changes in phenological patterns in response to the effects of climate change. Climate regulates the phenology of ferns and climatic triggers influence plants in tropical and subtropical regions differently. This study analyzed and compared the phenology of fern communities of three sub-areas - natural edge, artificial edge, and forest interior - of a fragment of Araucaria Forest in the Floresta Nacional de São Francisco de Paula, Rio Grande do Sul, Brazil, and its relationship with meteorological, astronomical, and edaphic variables. Abiotic and edaphic data were monitored concomitantly with phenological data (leaf renewal and senescence and sporangia formation) in each sub-area over a biennium. Temperature, air humidity, and soil moisture, which undergo changes with the edge effect, influenced edge plants. Leaf renewal was the main phenophase showing strong indication of changes in vegetative patterns in natural and artificial edge communities. Among the communities, that of the artificial edge signaled phenological changes that could compromise the development of ferns if effects intensify over time. In this respect, the phenology of artificial edge ferns differed from that of plants growing in originally natural formations (natural edge and forest interior), showing that exogenous transformations represent a new environmental situation for ferns to develop.
Assuntos
Araucaria , Gleiquênias , Florestas , Ecossistema , Microclima , Estações do AnoRESUMO
Courtyards have been used over many centuries as an interesting architectural feature that extends the living area, with good opportunities for relaxation, contemplation, and also for social interactions in such interface with the outdoor environment. Those areas can also act as climate modifiers and have tempering effects in hot regions. Depending on their geometrical features, courtyards can promote excellent shading and natural ventilation opportunities in tropical regions. This study is focused on the evaluation of two historic courtyards with very distinct solar exposure in a city located in a tropical savannah climate. Field monitoring was carried out alongside surveys with visitors to the courtyards. Results showed the potential of both courtyards in reducing the level of heat stress during peak daytime hours with their climate tempering function. The deeper courtyard yielded steadier cooling effect during daytime than the shallower one. Heat stress, here interpreted in terms of the universal thermal climate index (UTCI) was also more reduced in the deep courtyard. For the subjective part, there was a larger fluctuation of thermal sensation votes for a low level of heat stress in the shallower courtyard but less so and even an opposite pattern for higher heat stress. In essence, the geometric shape of the evaluated courtyards was considered to be paramount to provide thermal attenuation to their visitors due to the interplay between shading and solar access, even though the effect was not observed in their TS votes for increasing heat stress.
Assuntos
Microclima , Sensação Térmica , Cidades , Percepção , Clima TropicalRESUMO
In this study, we aimed to assess the spatial variability of microclimate inside a closed compost-bedded pack barn (CBP) with a negative ventilation system during summer and winter. The research was carried out in a CBP located in the Zona da Mata region, Minas Gerais, Brazil. For each of the stations analyzed, the following environmental mean variables observed inside a CBP were measured: air dry-bulb temperature (tdb), air relative humidity (RH), and windspeed, Temperature-Humidity index, and specific enthalpy. The kriging maps showed that the most critical housing conditions in the thermal environment were found, mainly, from the central part of the CBP, close to the exhaust fans. The analyses also pointed out that the system presented temperature gradients along the length, up to 3°C. During the summer afternoon, the entire region of the CBP was in a discomfort situation (tdb>26°C; RH>75%). During the winter, the measured environmental data remained within the comfort zone throughout the facility. However, probably due to the lack of thermal insulation of the material used to close the sides of the CBP, it did not allow spatial thermal uniformity for both seasons. It was also inefficient to keep the animals within the comfort zone for lactating cattle during the critical summer period.
Assuntos
Compostagem , Indústria de Laticínios , Animais , Bovinos , Feminino , Abrigo para Animais , Umidade , Lactação , Microclima , Estações do Ano , Análise Espacial , TemperaturaRESUMO
The objective of the present study was to investigate the influence of housing air temperature on the behavioural acts, physiological parameters and performance responses of fattening pigs. Animals were randomly allocated to 3 groups with 30 heads in each. During eight weeks of fattening, the animals of the two experimental groups were subjected to longterm technological temperature stress, provoked by a significant deviation of the microclimate parameters. The first control group of animals was kept following the Departmental Norms for Technological Design - Agro-Industrial Complex - 02.05 «Pig-breeding enterprises (complexes, farms, small farms)¼ at an air temperature of +17 +21 °C; pigs of the second experimental group were kept at a temperature of - +5 +8 °C, and the third experimental group - +28 +31 °C. During the experiment, the timing of behavioural acts and their index assessment, physiological parameters and productive characteristics of fattening pigs were studied. The experiment results showed that the thermoneutral zone for fattening pigs is + 17 + 21 °C. Animals 2nd experimental group showed less movement (P < 0.001), used huddling for decreasing body heat loss, more feed intake (P < 0.01), which increased its conversion, had reduced HR, RR, RT. Pigs of the 3rd experimental group showed increased movement (P < 0.001). This can be explained by their desire to find a cool place and rest lying on the side, consuming more water, having high HR, RR, and RT, showing signs of hyperthermia and were characterized by low-performance responses.
Assuntos
Animais , Suínos/crescimento & desenvolvimento , Suínos/psicologia , Comportamento Animal , Bem-Estar do Animal , Microclima , Aumento de PesoRESUMO
This study investigated the influence of the farm microclimate parameters in different seasons on the incidence of ketosis, foot diseases, reproductive diseases, and mastitis in three dairy farms of North Kazakhstan. Microclimate parameters were recorded in four seasons: summer, autumn, winter, and spring. The average temperature was 1.2 °C above the established norm in summer and 1.7 °C below the established norm in winter. The humidity was below the norm by 9.7% and 1.6% in summer and autumn, respectively, and above the norm by 9.6 % and 6.6 % in winter and spring, respectively. The airflow was 0.1 m/s lower than the norm in summer, winter, and spring. The general illumination was 3.8 and 2.6 LUX lower than the norm in winter and spring, respectively. The average morbidity (cumulative incidence of all four diseases) was 63.8% (highest) in the winter, followed by spring (60.0%). Average morbidity was considerably less in summer and autumn at 46.7% and 37.1%, respectively. Study results indicate that minor deviations in microclimate parameters from the norms, particularly in winter and spring, can considerably impact the disease incidence on dairy farms in Kazakhstan. The farm management should strive to maintain microclimate conditions on the farm as close to the norm as possible during different seasons to avoid losses from livestock morbidity.
Assuntos
Animais , Feminino , Bovinos , Sistema Urogenital/patologia , Cetose/complicações , Mastite Bovina/etiologia , Microclima , Temperatura Alta/efeitos adversosRESUMO
In Colombia, the second-largest exporter of cut flowers worldwide and one of the South American countries with the largest area of crops under cover, passive or naturally ventilated greenhouses predominate. Locally, there are several types of greenhouses that differ in architecture, size, height, shape of roof and ventilation surfaces, of which many characteristics of the microclimate generated in their interior environment are unknown. This generates productive limitations that in some way may be limiting the yield, quality and health of the final products harvested; in addition, Colombian producers do not have the ability to monitor the microclimate of their farms, much less to correlate microclimate data with data on crop production and yield. Therefore, there is a need for the Colombian grower to know the most relevant microclimate characteristics generated in the main greenhouses used locally. The objective of this work was to carry out a microclimatic characterization of the five most used types of greenhouses in Colombia. The main results allowed determining that in these structures, there are conditions of high humidity and low vapor pressure for several hours of the day, which affects the physiological processes of growth and development of the plants. It was also identified that for each type of greenhouse, depending on the level of radiation, there is a significant microclimatic heterogeneity that may be the cause of the heterogeneity in plant growth, which is a common characteristic observed by the technical cultivation personnel. Therefore, it can be concluded that it is urgent to propose microclimatic optimization strategies to help ensure the sustainability of the most important production systems in the country.
Assuntos
Produção Agrícola , Microclima , Colômbia , Fazendas , UmidadeRESUMO
The objective of this study was to analyze the effect of the rural and urban microclimate on the presence of mosquitoes. Temperature (T) and relative humidity (RH; indoors and outdoors), as well as mosquito richness and abundance were measured in two sites (urban and rural) of the Yucatan State, Mexico. Species richness was higher in the urban site, whereas mosquito abundance was higher in the rural site. The microclimates of urban and rural housing differently affect mosquito richness and abundance. Mosquito richness and abundance were higher outdoors than indoors in the urban site, but they were higher indoors than outdoors in the rural site. For the urban site, analysis of the relation of T and RH with the registered parameters revealed that species richness increased with increasing indoor RH, and that mosquito abundance increased with increasing indoor T and RH. In the rural site, species richness was not affected, but abundance increased with increasing T and RH (indoors as well as outdoors). Results are discussed in the context of the management of mosquito transmitted diseases. No IRB approval was necessary since no ethical implications were identified to be reviewed by the ethical committee for the research of the ECOSUR Institution.
Assuntos
Culicidae , Animais , México , Microclima , Mosquitos Vetores , População RuralRESUMO
Coffee berry disease (CBD) can cause significant coffee yield losses along with major income losses for African smallholders. Although these farmers cannot afford to purchase pesticides to control the disease, agroecological solutions have rarely been investigated, and how epidemiological mechanisms are linked to the environment of the coffee tree and the plot remains unclear. Agroforestry systems are a promising agroecological option, but the effect of shade on CBD regulation is the subject of debate, and the use of plant species diversity remains uncertain. Here, we address how shade affects epidemiological mechanisms by modifying the microclimate. For this purpose, we developed a mechanistic susceptible-exposed-infectious-removed model and used a Bayesian framework to infer the epidemiological parameters against microclimatic covariates. We show that shade has opposing effects on different epidemiological mechanisms. Specifically, shade can limit disease dynamics by reducing disease transmission while simultaneously promoting disease dynamics by reducing the latent period of the pathogen. However, in full sun, efficient disease transmission compensates for long latent periods. As a result, the balances between microclimatic variables can counterbalance the epidemiological rates, which can dramatically alter the fate of epidemics in shade versus full sun conditions. We propose research avenues to help design cost- and environmentally effective management strategies for CBD that are notably based on the functional traits of shade trees that could hamper CBD dispersal.
Assuntos
Coffea , Teorema de Bayes , Café , Microclima , Doenças das Plantas/prevenção & controleRESUMO
Surface urban heat islands (SUHIs) are one of the most studied phenomena in urban climates because they generate problems for the well-being of the urban population. This study analyzed the thermal comfort conditions at microclimate scale and SUHI for João Pessoa city, Brazil. Micrometeorological data (temperature and air humidity data) collected at 10 stations in 2011 and 2018 were used to calculate Thom's discomfort index (TDI) for João Pessoa city. Satellite images from Landsat 5/TM for 1991, 2006, and 2010 and Landsat 8/OLI for 2018 were used for land use and land cover classification and to identify SUHI. The obtained results highlighted that the SUHI area in João Pessoa city was 26 km2 and that almost half of the heat island area was concentrated in the Geisel, Aeroclube, Valentina, Distrito Industrial, Cristo Redentor, and Mangabeira neighborhoods. Regarding the micrometeorological data, higher values were obtained for 2018 in the dry periods (summer) and during the day. Based on the results, a considerable increase in discomfort during the daytime was observed in urbanized areas of the city from 2010 - 2018 due to the increase in the average temperature in João Pessoa between 1991 and 2018.
Assuntos
Temperatura Alta , Microclima , Brasil , Cidades , Monitoramento Ambiental/métodosRESUMO
Predictions of the magnitude and timing of leaf phenology in Amazonian forests remain highly controversial. Here, we use terrestrial LiDAR surveys every two weeks spanning wet and dry seasons in Central Amazonia to show that plant phenology varies strongly across vertical strata in old-growth forests, but is sensitive to disturbances arising from forest fragmentation. In combination with continuous microclimate measurements, we find that when maximum daily temperatures reached 35 °C in the latter part of the dry season, the upper canopy of large trees in undisturbed forests lost plant material. In contrast, the understory greened up with increased light availability driven by the upper canopy loss, alongside increases in solar radiation, even during periods of drier soil and atmospheric conditions. However, persistently high temperatures in forest edges exacerbated the upper canopy losses of large trees throughout the dry season, whereas the understory in these light-rich environments was less dependent on the altered upper canopy structure. Our findings reveal a strong influence of edge effects on phenological controls in wet forests of Central Amazonia.
Assuntos
Florestas , Folhas de Planta/fisiologia , Árvores/fisiologia , Brasil , Luz , Microclima , Estações do Ano , Solo/química , Água/químicaRESUMO
Insectivores of the tropical rainforest floor are consistently among the most vulnerable birds to forest clearing and fragmentation. Several hypotheses attempt to explain this pattern, including sensitivity to extreme microclimates found near forest borders, particularly brighter and warmer conditions. Importantly, this "microclimate hypothesis" has additional implications for intact forest under global climate change that could be evaluated through direct assessment of the light and temperature environment of terrestrial insectivores. In this study, we harness novel technology to directly quantify the light and thermal niches of 10 species of terrestrial insectivores in undisturbed Amazonian rainforest. Loggers placed on birds (N = 33) and their environment (N = 9) recorded nearly continuous microclimate data from 2017 to 2019, amassing >5 million measurements. We found that midday light intensity in tree fall gaps (~39,000 lux) was >40 times higher than at the ground level of forest interior (950 lux). Light intensity registered by sensors placed on birds averaged 17.4 (range 3.9-41.5) lux, with species using only 4.3% (0.9%-10.4%) of available light on the forest floor. Birds therefore selected very dark microhabitats-the light environment was >2200 times brighter in tree fall gaps. Bird thermal niche was a function of ambient temperature as well as body temperature, which averaged >40.5°C but varied among species. Forest floor temperature peaked daily at 27.0°C, whereas bird loggers averaged 35.1°C (34.5-35.7°C) at midday. The antpitta Myrmothera campanisona and the antthrush Formicarius colma used thermal conditions closest to their body temperatures, whereas leaftossers (Sclerurus spp.) and Myrmornis torquata occupied relatively cool microclimates. We found no general link between abundance trends and variation in species-specific light and thermal niches. However, all species occupied markedly dim and cool microclimates. Because such conditions are rare outside the interior of primary forest, these results support the microclimate hypothesis in disturbed landscapes. Moreover, strong avoidance of conditions that are becoming more common under climate change highlights the vulnerability of terrestrial insectivores even in the absence of disturbance and may be the reason for enigmatic declines in Amazonia and elsewhere.