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1.
Int J Biometeorol ; 64(10): 1675-1686, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32642793

RESUMO

Trees are considered to be an effective tool for improving human thermal comfort in hot climates and have been widely used in landscape architecture. However, it is not always clear how trees affect human-environment energy fluxes. In this study, an in-depth analysis of four common tree species was undertaken based on comprehensive field measurements, in terms of how each tree and its characteristics affected the energy fluxes of a person in a humid subtropical climate region. Results showed that the largest effect of trees was on radiation fluxes, with a much smaller effect on the convective and evaporative fluxes. For a person standing in shade, a tree can reduce approximately 25% of the absorbed radiation compared with an open reference point. Moreover, the cooling effect on radiation components was found to be greater in the solar radiation domain than in the terrestrial radiation domain. Solar radiation and ground surface temperature had the largest effect on a human energy budget, which was affected by characteristics of the trees and the thermophysical properties of ground surfaces. The effect from relative humidity and wind speed was quite minimal. For the four common tree species in this study, Ficus microcarpa had the best thermal performance by reducing the most absorbed solar radiation flux. This study shows a detailed empirical research about the thermal effects of trees on a person, providing recommendations for tree species selection in urban design.


Assuntos
Microclima , Árvores , Clima , Humanos , Umidade , Temperatura , Vento
2.
J Nurs Adm ; 50(7-8): 385-394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701643

RESUMO

OBJECTIVES: Study objectives were to: 1) explore how nursing care quality data (NCQD) was understood and interpreted; and 2) identify, compare, and contrast individual and group responses. BACKGROUND: Little evidence exists on how to best disseminate NCQD information. This study explores the outcomes of implementing an NCQD and human-interest information slide show across an inpatient surgery nursing service line using electronic screens. METHODS: Methods included semistructured interviews, qualitative analysis, and diagramming. RESULTS: The human-interest content most often attracted viewers' attention, but they were also exposed to NCQD. Interpretations and understandings differed among groups and between individuals. Among staff members, the human-interest content facilitated team-building, whereas NCQD provided meaningful recognition. Nursing care quality data evidenced the efforts that were being made to improve and provide excellent patient care. CONCLUSIONS: Using innovative dissemination methods can enhance understanding of NCQD among clinical providers. Creating microclimates of change and innovation within complex healthcare environments can benefit staff members and patients.


Assuntos
Disseminação de Informação , Microclima , Cuidados de Enfermagem/normas , Inovação Organizacional , Qualidade da Assistência à Saúde/normas , Adulto , Feminino , Humanos , Entrevistas como Assunto , Recursos Humanos de Enfermagem no Hospital/normas , Televisão
3.
Science ; 368(6492): 772-775, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32409476

RESUMO

Climate warming is causing a shift in biological communities in favor of warm-affinity species (i.e., thermophilization). Species responses often lag behind climate warming, but the reasons for such lags remain largely unknown. Here, we analyzed multidecadal understory microclimate dynamics in European forests and show that thermophilization and the climatic lag in forest plant communities are primarily controlled by microclimate. Increasing tree canopy cover reduces warming rates inside forests, but loss of canopy cover leads to increased local heat that exacerbates the disequilibrium between community responses and climate change. Reciprocal effects between plants and microclimates are key to understanding the response of forest biodiversity and functioning to climate and land-use changes.


Assuntos
Florestas , Aquecimento Global , Microclima , Árvores/fisiologia , Europa (Continente)
4.
Sci Total Environ ; 731: 139252, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32413649

RESUMO

In agroforestry systems, trees modify climatic parameters over a given area and create a complex microclimate through interactions between topography, plant composition and organizational structure of trees. In this way, indicators such as surface temperature of tree canopy and pasture, monitored by infrared thermography, are important to monitor the thermal environment of animal production and pasture establishment. Goals of this study were (1) to evaluate temporal and local variations of temperature and humidity leaf surface of tree canopy and pasture in agroforestry systems by infrared remote sensing and, (2) to validate infrared thermography as a potential tool for assessment microclimate in agroforestry systems. The study was carried out between June 2015 and February 2016 in an experimental area located at 54°370'W, 20°270'S and 530 m altitude, in Brazil. Surface temperatures and humidity of tree canopy and pasture in two agroforestry systems with different densities and tree spatial arrangements were determined using infrared thermography. Air, black globe and dew point temperatures, relative humidity and wind speed were measured using digital thermo-hygrometers with datalogger. Moderate to strong associations have been identified between microclimate parameters and those monitored by means of thermography measurements (0.45 ≥ r ≤ 0.78), suggesting positive relationships and equally well explained by air temperature, black globe temperature and relative air humidity (R2 = 0.68 ≥ R2 ≤ 0.98). Variations in hourly averages of temperatures and humidity of pasture and tree canopy show similar patterns between seasons, with consistently higheraverages during summer and under full sun, indicating the existence of a thermal band with leaf temperatures above air temperature. Therefore, this work's findings support use of infrared thermography as a tool for microclimate assessment in agroforestry systems.


Assuntos
Microclima , Termografia , Animais , Brasil , Umidade , Temperatura
5.
Int J Biometeorol ; 64(8): 1355-1366, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32363522

RESUMO

Many children growing up in cities are spending less time outdoors to escape the heat. This is contributing to childhood obesity and the prospect of a range of diseases in adulthood. When landscape architects and urban designers use a human thermal comfort model to test their designs for children's comfort, they would have to use a model essentially designed to simulate healthy adults. Yet there are many differences between the body of a child and an adult. The aim of this paper was to modify the thermal comfort model COMFA into a children's energy budget model through the consideration of the heat exchange of a child. The energy budget of a child can be up to 21 W/m2 higher than adults in hot summertime conditions, and 26 W/m2 lower in cold conditions. The model was validated through field studies of 65 children (32 boys and 33 girls) aged from 7-12 years old in 9 days from March to June in 2019, in 68 different microclimates ranging from cool to hot. A 5-point thermal comfort scale of energy budget for children was created using multinomial logistic regression, which revealed that children have a different range of thermal acceptability than adults. The frequency distribution of the actual thermal sensation and the predicted thermal comfort was improved using the new scale. The actual thermal sensation responses from children and the predicted thermal sensation using the model was determined to be positively significantly related. The accuracy of the model was 93.26%. This study has provided an effective children's energy budget model to predict children's thermal comfort. Its application can contribute to the design of thermally comfortable children's outdoor play areas by landscape architects and urban designers.


Assuntos
Microclima , Sensação Térmica , Adulto , Criança , Cidades , Feminino , Temperatura Alta , Humanos , Masculino
6.
Science ; 368(6492): 711-712, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32409462
7.
PLoS One ; 15(4): e0232004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320452

RESUMO

The goal of this research was to evaluate the microclimate (temperature, relative humidity and ECI-enthalpy comfort index) of commercial loads of broiler chickens at different transport distances: Dist15 (15 km on average) and Dist90 (90 km on average) in the summer and winter seasons and their effects on the production parameters body weight difference (BWD), mortality (%) and bruising prevalence (%). Twelve broiler loads were monitored using dataloggers to record temperature and humidity, with a total of 24 target crates per load. The experiment followed a factorial design [2 seasons (rainy and dry) × 2 distances (Dist15 and Dist90)] with a randomized complete block arrangement, 3 sexes (all males, all females, or mixed shipments) and one shipment per combination. BWD had a heterogeneous distribution throughout the load, and this distribution was not significantly correlated with the mean ECI measured during transport at 12 positions along the load. In terms of comfort, summer is the most critical period for broiler transport. In the interaction between rainy season and Dist90, the highest ECI was scored in the lethal zone (where physiological mechanisms are not enough to control body temperature). Mortality during the rainy season was not significantly different between distances. However, during the dry season, mortality was twice as high as broilers that travelled for 15 km. The prevalence of bruising on carcasses was not affected by the interaction between season and distance. As we know, broiler chicken performance, during transport, can be also related to road conditions, being hard to evaluate the real impact of seasons and distances on animal welfare. Load microclimate can compromise broiler chicken welfare during transport and it does not necessary reflect significant losses pre and post-slaughter.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Veículos Automotores , Matadouros , Criação de Animais Domésticos/estatística & dados numéricos , Bem-Estar do Animal , Animais , Peso Corporal , Brasil , Feminino , Umidade , Masculino , Microclima , Mortalidade , Análise de Componente Principal , Chuva , Estações do Ano , Temperatura , Fatores de Tempo
8.
PLoS One ; 15(4): e0230868, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240222

RESUMO

California's coastal climate is characterized by rainy winters followed by a dry summer season that is supplemented by frequent fog. While rising temperatures and drought caused massive tree mortality in central California during the 2011-2015 extreme drought, dying trees were less common in the central coast region. We hypothesized that cooler, maritime-ameliorated temperatures reduced the effects of drought stress on coastal vegetation. To test this, weekly measurements of water potential and stomatal conductance were made on two coast evergreen tree species, Arbutus menziesii and Quercus agrifolia, throughout the summer 2014 dry season. Water potential remained generally constant during this period but stomatal conductance declined in both species as the dry season progressed. Species' resistance to embolism was determined using the centrifuge method, and showed Q. agrifolia to be more vulnerable to embolism than A. menziesii. The stem vulnerability curves were consistent with species' seasonal water relations as well as their anatomy; the ring-porous Q. agrifolia had substantially larger conduits than the diffuse-porous A. menziesii. Leaf turgor loss points differed significantly as did other pressure-volume parameters but these data were consistent with the trees' seasonal water relations. Overall, the two species appear to employ differing water use strategies; A. menziesii is more profligate in its water use, while Q. agrifolia is more conservative, with a narrower safety margin against drought-induced loss of xylem transport capacity. Despite the extended drought, these species exhibited neither branch die-back nor any obvious symptoms of pronounced water-stress during the study period, implying that the maritime climate of California's central coast may buffer the local vegetation against the severe effects of prolonged drought.


Assuntos
Desidratação/metabolismo , Ericaceae/metabolismo , Quercus/metabolismo , California , Clima , Secas , Ecossistema , Microclima , Folhas de Planta/metabolismo , Estações do Ano , Temperatura , Árvores/metabolismo , Água , Xilema/metabolismo
9.
PLoS One ; 15(4): e0231316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294132

RESUMO

Chinese solar greenhouses are unique facility agriculture buildings and widely used in northeastern China, providing a favorable requirement for crop growth. The north wall configurations play an essential role in heat storage and thermal insulation and directly affect the management of the internal environment. This research is devoted to further improve the thermal performance of the greenhouse and explore the potential of the north wall. A mathematical model was designed to investigate the concave-convex wall configurations based on computational fluid dynamics. Four passive heat-storage north walls were analyzed by using the same constituent materials, including a plane wall, a vertical wall, a horizontal wall and an alveolate wall. The numerical model was validated by experimental measurements. The temperature distributions of the north walls were examined and a comparative analysis of the heat storage-release capabilities was carried out. The results showed that the heat-storage capacity of the north wall is affected by the surface structure. Moreover, the critical factor influencing the air temperature is the sum of the heat load released by the wall and the energy increment of greenhouse air. The results suggested that the alveolate wall has preferable thermal accumulation capacity. The concave-convex wall configurations have a wider range of heat transfer performance along the thickness direction, while the plane wall has a superior thermal environment. This study provides a basic theoretical reference to rationally design the internal surface structures of the north wall.


Assuntos
Agricultura/métodos , Arquitetura de Instituições de Saúde/métodos , Hidrodinâmica , Microclima , Modelos Teóricos , China , Temperatura Alta , Ciência dos Materiais , Luz Solar , Temperatura , Termodinâmica
10.
Sci Total Environ ; 721: 137741, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32179347

RESUMO

Extreme heat and associated health risks increasingly become threats to urban populations, especially in developing countries of the tropics. Although human thermal exposure in cities has been studied across the globe, current narratives insufficiently discuss mixed-used spaces, informal economic activity settings, and informal settlements. This study assessed outdoor human thermal comfort in the tropical city of Kolkata, India where uncomfortable hot and humid climatic conditions prevail year-round. Thermal Comfort Perception Surveys (TCPS) and biometeorological observations were conducted during summer and winter in three microentrepreneurial neighborhoods (Kumartuli, Boipara, and Mallickghat). A one-way ANOVA was performed to investigate the variance in Physiologically Equivalent Temperature (PET) values of 318 survey samples across neighborhoods. Through multiple linear regression and ANCOVA, significant relationships were established between various climatic and non-climatic parameters. No respondent reported a neutral thermal sensation during the summer. Annual neutral PET across neighborhoods was 23.6 °C with a neutral PET range of 19.5 °C to 27.6 °C. Annual neutral PET was 22.7 °C and 26.5 °C in Mallickghat and Boipara, respectively. Respondents in Boipara were more sensitive towards warmer sensation than in Mallickghat. Even in the winter, people reported warmer sensation votes. PET was a better predictor of the mean Thermal Sensation Vote (mTSV) compared to air temperature. In a few cases, acclimatization and expectations improved thermal comfort. Results can be useful in formulating strategies towards improving outdoor microclimate and heat health in tropical cities.


Assuntos
Microclima , Sensação Térmica , Cidades , Humanos , Índia , Estações do Ano
11.
Int J Biometeorol ; 64(5): 881-888, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32152728

RESUMO

The objective of this study was to assess the use of infrared thermography as a microclimate-evaluating tool and an estimate of the thermal comfort provided by four types of tree to cattle under grazing conditions in the central region of Brazil. The experiment was conducted at the Embrapa Beef Cattle Company, in Campo Grande, MS, Brazil, from June to August 2015. Evaluations were carried out over four consecutive days, at 1-hour intervals, from 8:00 a.m. to 4:00 p.m. (local time; GMT - 4:00). Infrared thermography images of tree crowns and soil surface underneath them from the shadow projection of four tree species native to the Brazilian cerrado (savannah-like) biome were obtained. The microclimate was assessed by estimation of thermal indices: temperature and humidity index, black globe, and radiation thermal load. The previous was calculated based on records of air temperature, dew point temperature, black globe temperature, air relative humidity, wind speed, and solar radiation. The geometrical settings of the trees were assessed for each tree component. Five thematic groups were formed based on multiple factor analysis that summarizes three synthetic analytical dimensions to explain the total variance among the studied elements and the existing correlations between groups. Positive linear correlations were found between thermography and the temperature measurements, thermal comfort indices, and radiation, suggesting that infrared thermography can be used as a tool for estimating and monitoring the microclimate and thermal comfort, presenting a potential use of measurement in agroforestry systems.


Assuntos
Gado , Termografia , Animais , Brasil , Bovinos , Umidade , Microclima , Temperatura
12.
An Acad Bras Cienc ; 92(suppl 1): e20180425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159584

RESUMO

The aim of the present study was to assess the effect of Eucalyptus trees in a silvopastoral system on the microclimate and the capacity of that to mitigate the effects of climate change on pasturelands. This study included an open pasture of Piatã palisadegrass and an adjacent pasture that contained both palisadegrass and East-to-West rows of Eucalyptus trees, with 15 m between rows, 2 m between trees within rows. The micrometeorological measurements were collected at several distances from the tree rows and in the open pasture. The silvopastoral system was associated with greater between-row shading when solar declination was high and greater near-tree shading when solar declination was around -22°. Both soil heat flux and temperature were influenced by solar radiation, wind speed, and the ability of tree canopies to reduce radiation losses. Wind speed was consistently lower in the silvopastoral system, owing to the windbreak effect of the Eucalyptus trees. The present study demonstrated that silvopastoral systems can be used to attenuate the effects of climate change, as trees can protect pastureland from intense solar radiation and wind, thereby reducing evapotranspiration and, consequently, improving soil water availability for the understory crop.


Assuntos
Mudança Climática , Eucalyptus , Agricultura Florestal , Pradaria , Brasil , Eucalyptus/crescimento & desenvolvimento , Umidade , Microclima , Estações do Ano , Solo , Luz Solar , Vento
13.
Sci Total Environ ; 720: 137518, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32143039

RESUMO

Hydrological and microclimatic changes after insect-induced tree dieback were evaluated in an unmanaged central European mountain (Plesné, PL) forest and compared to climate-related changes in a similar, but almost intact (Certovo, CT) control forest during two decades. From 2004 to 2008, 93% of Norway spruce trees were killed by a bark beetle outbreak, and the entire PL area was left to subsequent natural development. We observed that (1) climate-related increases in daily mean air temperature (2 m above ground) were 1.6 and 0.5 °C on an annual and growing season basis, respectively, and an increase in daily mean soil temperature (5 cm below ground) was 0.9 °C during growing seasons at the CT control from 2004 to 2017; (2) daily mean soil and air temperatures increased by 0.7-1.2 °C on average more at the disturbed PL plots than in the healthy forest; (3) water input to soils increased by 20% but decreased by 17% at elevations of 1122 and 1334 m, respectively, due to decreased occult deposition to, and evaporation from, canopies after tree dieback; (4) soil moisture was 5% higher on average (but up to 17% higher in dry summer months) in the upper PL soil horizons for 5-6 years following the tree dieback; (5) run-off from the PL forest ~6% (~70 mm yr-1) increased relatively to the CT forest (but without extreme peak flows and erosion events) after tree dieback due to the ceased transpiration of dead trees and elevated water input to soils; and (6) relative air humidity was 4% lower on average at disturbed plots than beneath living trees. The rapid tree regeneration during the decade following tree dieback resulted in a complete recovery in soil moisture, a slow recovery of discharge and air humidity, but a still insignificant recovery in air and soil temperatures.


Assuntos
Microclima , Árvores , Florestas , Hidrologia , Noruega , Solo
15.
Environ Entomol ; 49(2): 296-303, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32108235

RESUMO

The temperature of the nest influences fitness in cavity-nesting bees. Females may choose nest cavities that mitigate their offspring's exposure to stressful temperatures. This study aims to understand how cavity temperature impacts the nesting preference of the solitary bee Megachile rotundata (Fabricius) under field conditions. We designed and 3D printed nest boxes that measured the temperatures of 432 cavities. Nest boxes were four-sided with cavity entrances facing northeast, northwest, southeast, and southwest. Nest boxes were placed along an alfalfa field in Fargo, ND and were observed daily for completed nests. Our study found that cavity temperature varied by direction the cavity faced and by the position of the cavity within the nest box. The southwest sides recorded the highest maximum temperatures while the northeast sides recorded the lowest maximum temperatures. Nesting females filled cavities on the north-facing sides faster than cavities on the south-facing sides. The bees preferred to nest in cavities with lower average temperatures during foraging hours, and cavities that faced to the north. The direction the cavity faced was associated with the number of offspring per nest. The southwest-facing cavities had fewer offspring than nests on the northeast side. Our study indicates that the nesting box acts as a microclimate, with temperature varying by position and direction of the cavity. Variation in cavity temperature affected where females chose to nest, but not their reproductive investment.


Assuntos
Himenópteros , Animais , Abelhas , Feminino , Microclima , Comportamento de Nidação , Reprodução , Temperatura
16.
Oecologia ; 192(3): 657-669, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006183

RESUMO

Accurate evaluation of habitat availability for wildlife is relevant for ecological applications. Researchers have frequently used models to simulate habitats thermally suitable for reptiles, but these results have limited application for species highly selective for habitat humidity. Here, we use the biophysical Niche Mapper™ model to investigate impacts of vegetation cover on the habitat quality of a high-elevation forest skink, Sphenomorphus taiwanensis, and to predict changes in habitat suitability in a future warmer climate (3 °C increase in air temperature). We assess habitat suitability with different densities of canopy cover in our study areas using two ecologically relevant estimates for lizards: maximum activity time and evaporative water loss (EWL) during the activity season. We measured preferred body temperature and EWL of this species for model parameterization, and behavioral response to EWL to supplement habitat quality assessment. The results indicated that this species is sensitive to EWL and reduces its activity when dehydrated. The model predicted that denser canopy levels increase microclimate cooling and humidity, and that most canopy levels are thermally suitable for this species, as the lizard can thermoregulate to manage adverse temperatures. Nevertheless, increasing canopy density could significantly decrease EWL during activity. In the warmer climate scenario, simulated maximum activity time and EWL changed little because of thermoregulation behavior. Our results suggest that habitat preference of this species is a consequence of water and energy requirements, and we note that combining EWL and maximum activity time data can enhance model accuracy of lizards' habitat quality in a warmer climate.


Assuntos
Lagartos , Água , Animais , Ecossistema , Florestas , Microclima
17.
Int J Biometeorol ; 64(4): 571-584, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31907654

RESUMO

Impacts of climate change (e.g., abnormal growth in plants, early flowering, and shifting vegetation zones) are being detected throughout the world. Urban land use and its resulting microclimates work in conjunction with the impacts of climate change. Among the principal environmental signals that modulate bud flush, only temperature has changed significantly in recent years. Throughout South Korea, abnormal shoots (usually known as lammas shoots) in Korean red pine (Pinus densiflora), which were once a rare phenomenon, have become notably more common in recent years. The phenomenon is prominent in urban site of each local area. These abnormal shoots appear at a higher frequency and grow to longer lengths in Seoul's hotter urban center than in suburban sites and showed a close positive correlation with urban density and a close negative correlation with vegetation cover expressed as NDVI. Differences in temperature among the urban center, urban edge, and suburban greenbelt were significantly correlated with land-use intensity. Korean red pines planted in urban parks at sites in urban centers showed a lower frequency of abnormal shoots, and the length of the shoots was shorter, compared with those at the other urban sites. Furthermore, the phenology of Korean red pines in an urban park with a fountain showed a spatial difference, depending upon the distance from the fountain: pine trees close to the fountain did not produce abnormal shoots, but abnormal shoot growth increased with the distance from the fountain. These results are noteworthy because they are related to the cooling effects of evapotranspiration from vegetated landscapes and evaporation from a water body. From the results of this study, we could confirm that microclimate change due to urbanization accelerates the impacts of climate change on plant phenology. Furthermore, we identified the possibility that judicious land-use planning could contribute to minimizing the adverse effects of climate change.


Assuntos
Pinus , Urbanização , Microclima , República da Coreia , Seul
18.
Sci Rep ; 10(1): 1366, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992825

RESUMO

High-alpine ecosystems are commonly assumed to be particularly endangered by climate warming. Recent research, however, suggests that the heterogeneous topography of alpine landscapes provide microclimatic niches for alpine plants (i.e. soil temperatures that support the establishment and reproduction of species). Whether the microclimatic heterogeneity also affects diversity or species interactions on higher trophic levels remains unknown. Here we show that variation in mean seasonal soil temperature within an alpine pasture is within the same range as in plots differing in nearly 500 m in elevation. This pronounced heterogeneity of soil temperature among plots affected the spatial distribution of flowering plant species in our study area with a higher plant richness and cover in warmer plots. This increased plant productivity in warmer plots positively affected richness of flower visitor taxa as well as interaction frequency. Additionally, flower-visitor networks were more generalized in plots with higher plant cover. These results suggest that soil temperature directly affects plant diversity and productivity and indirectly affects network stability. The strong effect of heterogeneous soil temperature on plant communities and their interaction partners may also mitigate climate warming impacts by enabling plants to track their suitable temperature niches within a confined area.


Assuntos
Altitude , Ecossistema , Microclima , Modelos Biológicos , Pinus/crescimento & desenvolvimento
19.
BMC Plant Biol ; 20(1): 27, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952478

RESUMO

BACKGROUND: Rain-shelter covering is widely applied during cherry fruit development in subtropical monsoon climates with the aim of decreasing the dropping and cracking of fruit caused by excessive rainfall. Under rain-shelter covering, the characteristics of the leaves and fruit of the cherry plant may adapt to the changes in the microclimate. However, the molecular mechanism underlying such adaptation remains unclear, although clarifying it may be helpful for improving the yield and quality of cherry under rain-shelter covering. RESULTS: To better understand the regulation and adaptive mechanism of cherry under rain-shelter covering, 38,621 and 3584 differentially expressed genes were identified with a combination of Illumina HiSeq and single-molecule real-time sequencing in leaves and fruits, respectively, at three developmental stages. Among these, key genes, such as those encoding photosynthetic-antenna proteins (Lhca and Lhcb) and photosynthetic electron transporters (PsbP, PsbR, PsbY, and PetF), were up-regulated following the application of rain-shelter covering, leading to increased efficiency of light utilization. The mRNA levels of genes involved in carbon fixation, namely, rbcL and rbcS, were clearly increased compared with those under shelter-free conditions, resulting in improved CO2 utilization. Furthermore, the transcription levels of genes involved in chlorophyll (hemA, hemN, and chlH) and carotenoid synthesis (crtB, PDS, crtISO, and lcyB) in the sheltered leaves peaked earlier than those in the unsheltered leaves, thereby promoting organic matter accumulation in leaves. Remarkably, the expression levels of key genes involved in the metabolic pathways of phenylpropanoid (PAL, C4H, and 4CL) and flavonoid (CHS, CHI, F3'H, DFR, and ANS) in the sheltered fruits were also up-regulated earlier than of those in the unsheltered fruits, conducive to an increase in anthocyanin content in the fruits. CONCLUSIONS: According to the physiological indicators and transcriptional expression levels of the related genes, the adaptive regulation mechanism of cherry plants was systematically revealed. These findings can help understand the effect of rain-shelter covering on Chinese cherry cultivation in rainy regions.


Assuntos
Produção Agrícola , Microclima , Prunus/genética , Transcriptoma , Adaptação Biológica , Produção Agrícola/métodos , Perfilação da Expressão Gênica , Prunus/crescimento & desenvolvimento
20.
Sci Total Environ ; 711: 134649, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31831241

RESUMO

This paper studies the impact of different green barriers on the dispersion of air pollution in a neighbourhood. The study was performed with reference to air quality conditions in Manchester, UK. Manchester experiences a high level of NO2. Measured results showed that the average annual concentration level in 2018 was very close to the limit defined by European Union legislation. Maximum and minimum NO2 concentrations occurred during the winter and summer, respectively. Simulations of the dispersion of air pollution in a hypothetical neighbourhood showed that NO2 level was decreased by the increase of air temperature during the simulated day. In four perturbation scenarios, hedges and trees with different heights were added to the neighbourhood as green barriers. Hedges increased the pollution level near the street at the pedestrian level as a result of the reduced wind speed. The simulations demonstrated that using the trees facilitated the dispersion of pollution.


Assuntos
Microclima , Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Vento
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