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Stauroneis (Naviculales, Bacillariaceae) are widespread, mostly in fresh-water habitats, and account for 343 species. They are described mainly on the basis of morphology and morphometric traits. These characteristics vary during life cycles and may overlap between species, making their identification difficult. We isolated two strains of naviculoid diatoms and examined them using an integrative approach (phylogenetic, morphological, ultrastructural data, and life cycle). Phylogenetic analyses based on chloroplast rbcL gene data showed affinity of the new strains to the genus Stauroneis. Our algae share morphological features typical of Stauroneis but differ from similar species in minimal valve length measurements, valve apex shape, and minimal number of striae in 10 µm. Two strains are distinct from each other in maximal valve length and width, partially valve shape, the number of areolae in 10 µm, and cingulum structure. It was revealed that the strains reproduce via isogamy. Three species delimitation methods (ASAP, PTP, and GMYC) also confirmed that the two closely related new strains represent distinct species. Based on molecular data and phenotypic traits examined within the framework of an integrative approach, we describe two new isolates as Stauroneis urbani sp. nov. and Stauroneis edaphica sp. nov.
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Exploring the spatiotemporal dynamic evolution of local climate zones (LCZ) associated with changes in land surface temperature (LST) can help urban planners deeply understand urban climate. Firstly, we monitored the evolution of 3D urban spatial form in Chengdu City, Sichuan Province, China from 2010 to 2020, used the ordinary least squares model to fit the dynamic correlation (DR) between the changes in urban spatial patterns and changes in LST, and revealed the changes of urban spatial patterns closely related to the rise in LST. Secondly, the spatiotemporal patterns of LST were examined by the integration of the Space-Time Cube model and emerging hotspot analysis. Finally, a prediction model based on curve fitting and random forest was integrated to simulate the LST of study area in 2025. Results show the following: the evolution of the urban spatial form consists of three stages: initial incremental expansion, midterm incremental expansion and stock renewal, and late stock renewal and ecological transformation. The influence of the built environment on the rise of LST is greater than that of the natural environment, and the building density has a greater effect than the building height. The overall LST shows a warming trend, and the seven identified LST spatiotemporal patterns are dominated by oscillating and new hotspots patterns, accounting for 51.99 and 11.44% of the study area, respectively. The DR between urban spatial form and LST varies across different time periods and built environment types, whereas the natural environment is always positively correlated with LST. The thermal environment of the city will warm up in the future, and the area affected by the heat island will shift to the central of the city.
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Cidades , Análise Espaço-Temporal , Temperatura , China , Humanos , Planejamento de Cidades , Urbanização , Mudança Climática , ClimaRESUMO
Urban blue-green infrastructure (BGI) offers a multitude of ecological advantages to residents, thereby playing a pivotal role in fortifying urban resilience and fostering the development of climate-resilient cities. Nonetheless, current research falls short of a comprehensive analysis of BGI's overall potential for carbon reduction and its indirect carbon reduction impact. To fill this research gap, we utilized the integrated valuation of ecosystem services and trade-offs model and remote sensing estimation algorithm to quantify the direct carbon sequestration and resultant indirect carbon reduction facilitated by the BGI within the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) (China). To identify the regions that made noteworthy contributions to carbon offsets and outliers, spatial autocorrelation analysis was also employed. The findings of this study reveal that in 2019, the BGI within the study area contributed an overall carbon offset of 1.5 × 108 t·C/yr, of which 3.5 × 107 and 11.0 × 107 t·C/yr were the result of direct carbon sequestration and indirect carbon reduction, respectively. The GBA's total CO2 emissions were 1.1 × 108 t in 2019. While the direct carbon sequestration offset 32.0% of carbon emissions, the indirect carbon reduction mitigated 49.9% of potential carbon emissions. These results highlight the critical importance of evaluating BGI's indirect contribution to carbon reduction. The findings of this study provide a valuable reference for shaping management policies that prioritize the protection and restoration of specific areas, thereby facilitating the harmonized development of carbon offset capabilities within urban agglomerations.
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Sequestro de Carbono , Carbono , Ecossistema , Cidades , ChinaRESUMO
Smart urban planning needs to have a multicriteria-based approach to prevent the deteriorating local thermal climate. Maximizing the cooling potential using the available grey infrastructure would be the utmost priority of future smart cities. Remote sensing and GIS can be the appropriate tools to develop a climate-resilient urban planning framework. Studies are needed to include different features of vertical and horizontal landscaping to mitigate heat stress and enhance liveability at the city level. With this goal, the current work outlined a holistic approach to efficiently using green spaces with minimal reconstruction. The problem of regional climate threat was evaluated with urban heat island characterization. Moran's I clustering identified nearly 12% of the study area to be under considerable heat stress during summer days. Multiple techniques, such as mapping local climate zones, segment mean shift-based roof extraction, vegetation index computation, solar azimuth-based green wall site selection, etc., were applied to formulate solutions and provide an integrated method for city-level environment enhancement. A considerable area was identified as most suitable for green roof cover, and it was also computed that the transition towards green roof at only these locations may bring down the maximum heat island intensity by 0.74 °C. Additionally, solar zenith, illumination effect, and building height information were combined to create a distinct method where vertical plantation would flourish exceptionally. A rigorous assessment of more than 130 urban green spaces further quantified the relation between landscape geometry and cooling effect to provide optimum green space designs for future urban planning.
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Within the study of the urban heat island (UHI) in Echirolles and Grenoble (France, the eastern part of the alpine arc), two temperature measurement networks have been deployed. The aim is to measure the temperature gradients associated with the UHI in summer. A total of 62 measurement points has been installed in the various neighborhoods on 3-meter-high streetlights, starting in summer 2019. The preliminary classification of the different neighborhood typologies according to ``Local Climate Zone'' guided the choice of location for the temperature sensors. These urban observations respond to a dual challenge: firstly, to observe temperature located in complex topographical situations with valleys, and secondly, to observe the urban climate in neighborhoods where social considerations are important. Municipalities of Echirolles and Grenoble were involved in the investigation. The ADEME-funded (The French Agency for Ecological Transition) CASSANDRE research program analyzes and processes these observations to study the vulnerability of inhabitants to heat waves and more generally to summer heat stress.
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INTRODUCTION: Global warming appears to initiate and aggravate allergic respiratory conditions via interaction with numerous environmental factors. Temperature, commonly identified as a factor in climate change, is important in this process. Allergic rhinitis, a common respiratory allergy, is on the rise and affects approximately 500 million individuals worldwide. The increasing ambient temperature requires evaluation regarding its influence on allergic rhinitis, taking into account regional climate zones. METHODS: A detailed search of PubMed, EMBASE, Scopus, Web of Science, MEDLINE, and CINAHL Plus databases, was conducted, encompassing observational studies published from 1991 to 2023. Original studies examining the relationship between increasing temperature and allergic rhinitis were assessed for eligibility followed by a risk of bias assessment. Random effects meta-analysis was utilized to measure the association between a 1 °C increase in temperature and allergic rhinitis-related outcomes. RESULTS: 20 studies were included in the qualitative synthesis, with nine of them subsequently selected for the quantitative synthesis. 20 included studies were rated as Level 4 evidence according to the Oxford Centre for Evidence-Based Medicine, and the majority of these reported good-quality evidence based on the Newcastle-Ottawa Quality Rating Scale. Using the Risk of Bias In Non-Randomized Studies of Exposure tool, the majority of studies exhibit a high risk of bias. Every 1 °C increase in temperature significantly raised the risk of allergic rhinitis-related outcomes by 29 % (RR = 1.26, 95 % CI: 1.11 to 1.50). Conversely, every 1 °C rise in temperature showed no significant increase in the odds of allergic rhinitis-related outcomes by 7 % (OR = 1.07, 95 % CI: 0.95 to 1.21). Subsequent subgroup analysis identified climate zone as an influential factor influencing this association. CONCLUSION: It is inconclusive to definitively suggest a harmful effect of increasing temperature exposure on allergic rhinitis, due overall very low certainty of evidence. Further original research with better methodological quality is required.
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Rinite Alérgica , Rinite Alérgica/epidemiologia , Humanos , Temperatura , Estudos Observacionais como Assunto , Mudança Climática , Aquecimento Global , Temperatura AltaRESUMO
Global climate zones are experiencing widespread shifts with ongoing rise in atmospheric CO2, influencing vegetation growth and shifting its distributions to challenge ecosystem structure and function, posing threats on ecological and societal safety. However, how rising atmospheric CO2 affects the pace of global climate zone shifts is highly uncertain. More attentions are urgently required to understand the underlying mechanisms and quantifications of regional climate vulnerability in response to rising CO2. In this study, we employ nine Earth system models from CMIP6 to investigate global climate zone shifts with rising CO2, unravel the effects of vegetation physiological response (PHY), and categorize climate vulnerable regions depending on the extent of climate zone shifts. We find that climate zone shifts over half of the global land area, 16.8% of which is contributed by PHY at 4 × CO2. Intriguingly, besides warming, PHY-induced precipitation changes and their interactions with warming dominate about two-fifths of PHY-forced shifts, providing potential direction for model improvement in future predictions of climate zone shifts. Aided with PHY effects, 4 × CO2 imposes substantial climate zone shifts over about one-fifth of the global land area, suggesting substantial changes in local climate and ecosystem structure and functions. Hence, those regions would experience strong climate vulnerability, and face high risk of climate extremes, water scarcity and food production. Our results quantitatively identify the vulnerable regions and unravel the underlying drivers, providing scientific insights to prioritize conservation and restoration efforts to ensure ecological and social safety globally.
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Dióxido de Carbono , Mudança Climática , Ecossistema , Dióxido de Carbono/análise , Atmosfera/químicaRESUMO
This study evaluates for the first time whether 33 species of annual and perennial herbaceous plants originating from a moderate climate continue to be capable of air filtration of particulate matter (PM) at the end of the growing season. Research was undertaken in November in two urban meadows located in trafficked areas of Bialystok (Poland). The study reveals that despite the lateness in the season, tested species remained capable of PM accumulation. Deposition of total PM exceeding 100 µg·cm-2 was found on S. vulgaris, S. latifolia, T. pratense, E. vulgare, and A. officinalis. The finest and most toxic fraction was accumulated most effectively by S. latifolia, E. vulgare, and L. vulgare (>12 µg·cm-2). Taraxacum officinale and M. sylvestris retained c. 60% of PM in their epicuticular wax. A slight significant correlation was found between rosette growth pattern and deposition of total PM on foliage, while the accumulation of the finest fraction was correlated with a simple leaf shape. These results support the usefulness of urban meadows as long-lasting air bio-filters provided that their composition includes species that have a confirmed, prolonged PM accumulation capacity and that the meadow is not mown in autumn.
This is the first time that the PM accumulation capacity of urban meadow species at the end of the vegetative season has been evaluated in real-life conditions. Evidence of prolonged PM deposition on herbaceous plants was obtained. To enhance PM mitigation in cities located in moderate climate zones, it is proposed that a selection of species be sown in urban meadows.
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Urban heat-islands reportedly expose densely populated areas to higher temperatures. However, the magnitude of the impact of extra hot-day exposure (EHDE) and its association with the effects of urbanization on a global scale remain unclear. As local climate zones (LCZs) refine the impact of differences in urban built-type on heat-island effects, this study aimed to quantify the global EHDE caused by the urban heat-island effect based on LCZs and explored the joint impacts of low gross-domestic product and an increasing vulnerable-age population on EHDE. The results showed that EHDE accounted for 48.01 % of overall hot-day exposure. Additionally, despite a significant geographic differentiation among LCZ types with the highest EHDE intensity, they are almost typically building-intensive LCZs. Furthermore, our study revealed regional differences in the structure of the EHDE share in LCZs, which support the adoption of targeted EHDE mitigation strategies.
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Most studies of terrestrial bryophytes as natural substrates for photosynthetic microorganisms have been performed in the polar regions, where bryophytes are an important part of the ecosystem. As they remain green throughout the year, bryophytes may also be an ideal substrate for epiphytic organisms in temperate regions. The present study investigated the colonization potential and diversity of microalgae on selected plant species in riparian forest and spruce monoculture in a temperate region. It examines whether the presence of algae is related to substrate humidity, the micromorphology of gametophyte or the seasonal availability of substrate. The taxonomic diversity of algae was studied. Cyanobacteria and green algae were cultured on BG-11 agar medium, while diatoms were identified in permanent diatomaceous slides. The alpha- and beta-diversity indices were calculated, and the communities were compared using Bray-Curtis distances and multidimensional correspondence analyses. Our findings indicate that the largest number of alga species were diatoms; however, their presence was only observed in riparian forest and was associated with high humidity. Both aerophilic and freshwater taxa were noted, the latter carried by water from nearby aquatic ecosystem. Green algae were present in both phytocoenoses and humidity appears to have no substantial effect on the degree of colonization; their diversity was low and the group consisted of terrestrial taxa. In two bryophytes growing at the highest humidity, cyanobacteria were only identified in culture. The key factor influencing the degree of microalgae colonization was the humidity of the substrate, which was related to the distance from water.
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This study contributes a first comparison of current and potential threats to Natural World Heritage Sites from climate change, as assessed by experts, when site and location characteristics (size, year of inscription to the World Heritage list, continent, climate zone and kind of site) are controlled for. The probability of a threat as well as its intensity is analysed. Another novelty lies in the use of data from the IUCN Conservation Outlook Assessment, covering all 245 Natural and Mixed World Heritage Sites across the world for three points in time: 2014, 2017 and 2020. The threat of climate change is broadly defined and includes temperature extremes, rising temperatures, disappearing glaciers, coral bleaching, droughts, desertification, and rising sea levels. Results based on a simultaneous Probit model with random effects show that the probability of actual and potential climate change threats increases over time, but with differences for size, kind of site and location. The probability that a threat is identified is highest for marine and coastal sites, and for those in Latin America, while it is significantly lower for sites on the African continent. Larger sites have a higher probability of being assessed as at risk and the severity of threats is found to be lower for recently inscribed sites. The rate at which the likelihood of a threat assessment increases is consistent for both current and future situations, while the probability of the most severe threat is larger for the current than the future period. A serious threat from climate change is assessed as highest for locations in the tropical monsoon (current period) or the tropical savannah climate (future period). Estimations also show that pure descriptive statistics or bivariate correlations may not correctly identify the risk or the dignity of a threat.
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Climate change has significantly altered the characteristics of climate zones, posing considerable challenges to ecosystems and biodiversity, particularly in Borneo, known for its high species density per unit area. This study aimed to classify the region into homogeneous climate groups based on long-term average behavior. The most effective parameters from the high-resolution daily gridded Princeton climate datasets spanning 65 years (1950-2014) were utilized, including rainfall, relative humidity (RH), temperatures (Tavg, Tmin, Tmax, and diurnal temperature range (DTR)), along with elevation data at 0.25° resolution. The FCM clustering method outperformed K-Mean and two Ward's hierarchical methods (WardD and WardD2) in classifying Borneo's climate zones based on multi-criteria assessment, exhibiting the lowest average distance (2.172-2.180) and the highest compromise programming index (CPI)-based correlation ranking among cluster averages across all climate parameters. Borneo's climate zones were categorized into four: 'Wet and cold' (WC) and 'Wet' (W) representing wetter zones, and 'Wet and hot' (WH) and 'Dry and hot' (DH) representing hotter zones, each with clearly defined boundaries. For future projection, EC-Earth3-Veg ranked first for all climate parameters across 961 grid points, emerging as the top-performing model. The linear scaling (LS) bias-corrected EC-Earth3-Veg model, as shown in the Taylor diagram, closely replicated the observed datasets, facilitating future climate zone reclassification. Improved performance across parameters was evident based on MAE (35.8-94.6%), MSE (57.0-99.5%), NRMSE (42.7-92.1%), PBIAS (100-108%), MD (23.0-85.3%), KGE (21.1-78.1%), and VE (5.1-9.1%), with closer replication of empirical probability distribution function (PDF) curves during the validation period. In the future, Borneo's climate zones will shift notably, with WC elongating southward along the mountainous spine, W forming an enclave over the north-central mountains, WH shifting northward and shrinking inland, and DH expanding northward along the western coast. Under SSP5-8.5, WC is expected to expand by 39% and 11% for the mid- and far-future periods, respectively, while W is set to shrink by 46%. WH is projected to expand by 2% and 8% for the mid- and far-future periods, respectively. Conversely, DH is expected to expand by 43% for the far-future period but shrink by 42% for the mid-future period. This study fills a gap by redefining Borneo's climate zones based on an increased number of effective parameters and projecting future shifts, utilizing advanced clustering methods (FCM) under CMIP6 scenarios. Importantly, it contributes by ranking GCMs using RIMs and CPI across multiple climate parameters, addressing a previous gap in GCM assessment. The study's findings can facilitate cross-border collaboration by providing a shared understanding of climate dynamics and informing joint environmental management and disaster response efforts.
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Mudança Climática , Bornéu , Temperatura , Ecossistema , Clima , ChuvaRESUMO
The environmental quality, in terms of acoustic, visual, and thermal environments, significantly affects people's comfort levels. Along these lines, in this work, their comprehensive impact on people's overall comfort was systematically explored. Pedestrians' outdoor neutral points on various environmental parameters were found by performing linear regressions. Similarly, people's thermal perceptions (indicated by neutral temperatures, NT) were found to vary for both acoustic and light environments. They would be increasingly heat sensitive (R2 increases) in a noisier environment while the NTs varied for either sound or light intensity levels. From our analysis, it was demonstrated that people's overall comforts were negatively correlated with these parameters in different degrees. This work provides valuable insights for future urban design and planning studies to create better outdoor environments.
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Pedestres , Sensação Térmica , Humanos , Pedestres/psicologia , Masculino , Feminino , Adulto , Estações do Ano , Luz , Adulto Jovem , Clima , Acústica , TemperaturaRESUMO
Megacities, such as Lagos, Nigeria, face significant challenges due to rapid urbanization and climate change, resulting in a higher intensity of the urban heat island effect, coupled with high population density, making the city fall under the category of moderate to high heat stress/risk. Despite this, very few studies have analyzed the urban impact on heat stress over the coastal city, albeit with poor resolution data. In this study, we assessed the performance of an integrated high-resolution WRF-urban scheme driven by the readily available urban canopy information of the local climate zone (LCZ) to simulate local meteorological data for analyzing the spatiotemporal pattern of heat stress over the megacity. Our results show that the WRF-BEP scheme outperformed the other evaluated urban schemes, reducing the normalized root mean squared error by 25%. Furthermore, using humidex, we found a generally high incidence of intense discomfort in highly urbanized areas and noted the significant influence of urban morphology on the pattern of heat stress, particularly at night due to the combined effect of urban warming and higher relative humidity. The most socioeconomically disadvantaged urban areas, LCZ7, were most affected, with "hot" heat stress conditions observed over 90% of the time. However, during the afternoon, we found reduced heat stress in the core urban areas which might be due to the shading effect and/or cold air advection. Our findings would be relevant in the development of the urgently needed climate/heat adaptation plans for the city and other sub-Saharan African cities.
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Cidades , Transtornos de Estresse por Calor , Nigéria , Humanos , Transtornos de Estresse por Calor/epidemiologia , Modelos Teóricos , Mudança Climática , Temperatura AltaRESUMO
Introduction: After 2000, there are more obese than underweight people in the world. We face a rapid increase in average global warming of 1.5°C, reported as a syndemic problem of three interconnected epidemics: obesity, global warming, and undernutrition. We aimed to analyze the impact and association between global warming and obesity in children and differences by gender across Europe after 2000. Methods: We searched PubMed, MEDLINE, Google Scholar, ScienceDirect, and Embase databases. The considered population were children aged 6-14. Only cross-sectional studies that defined obesity by the IOTF cutoffs and the subjects' place of residence, used to determine precise climate zones, were included. We assessed the prevalence of obesity and overweight using a random-effects and the Mantel-Haenszel fixed-effect method when heterogeneity was greater/lower than 50%. We did a subgroup analysis for prevalence across gender, obesity, and overweight, two decades, regions, countries, and the Köppen-Geiger climate zones. Random effects of the meta-regression were used to study the global warming impact and differences in trends across European countries by gender for both conditions separately. Results: We identified 114 studies that included 985,971 children from 39 European countries. A significant difference between genders was in favor of obese girls 4.78 (95% CI: 3.85-5.93) versus boys 5.76% (95% CI: 5.11-6.48, p = 0.03), respectively, but not for overweight children. Most of the obese girls were in South Europe 7.51% (95% CI: 6.61-8.51) versus East Europe 2.86% (95% CI: 23-3.12), versus boys in South Europe 8.66% (95% CI: 7.68-9.74) and North Europe 3.49% (95% CI: 2.90-4.19), respectively. The "cold" Köppen-Geiger climate zone, with lowest temperatures, has the largest trend rise between two decades of 2.8% and 1.53% for obese girls and boys, and 5.31% and 1.81% for overweight girls and boys, respectively, followed by the smallest number of obese girls 3.28% (95% CI: 2.17-4.92) and boys 3.58% (95% CI: 2.39-5.33), versus the zone with the highest temperatures "hot" for girls 7.02% (95% CI: 6.30-7.82) and for boys 8.23% (95% CI: 7.55-8.96), respectively. The meta-regression proved global warming has a significant impact on the distribution of obesity and overweight across climate zones, R2 = 0.52 and R2 = 0.22. No significant gender differences, or significant interaction, was noted. Conclusion: Our meta-analysis provides a comprehensive overview of the association between and impact of global warming on obesity. This impact increases obesity among children in Europe throughout all climate zones, and emphasizes an urgent call for further preventive methods in schools, since obesity differences continue their trend of disappearing into the future.Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021282127, identifier: CRD42021282127.
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Sobrepeso , Obesidade Infantil , Humanos , Criança , Feminino , Masculino , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Fatores Sexuais , Prevalência , Estudos TransversaisRESUMO
A strain of oogamous biflagellate green alga was isolated during a study on soil algal diversity in the Russian Far East (Sakhalin Region, Iturup Island) and examined using an integrative approach. Phylogenetic analyses, based on the SSU rDNA gene, resolved the new strain as a part of the RL clade (sensu Watanabe and Nakada) within Oogamochlamydinia (Volvocales, Chlorophyceae). The strain was similar to members of the genus Oogamochlamys (parietal and massive cup-shaped chloroplasts; two apical contractile vacuoles), but was, however, distinguished from them based on the size and shape of the mature vegetative cells, the flagellar length, the presence of only one pyrenoid in both the mature vegetative cells and the zoospores, the anterior nucleus position, and the spermatozoids' shape. Although a concept of the genus Oogamochlamys has been compromised in recent phylogenetic analysis based on the SSU rDNA sequence data and its likely affinity to anisogamous Chlamydomonas allensworthii, we described the strain from Iturup Island as Oogamochlamys kurilensis sp. nov.
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Diatoms inhabit different aquatic and non-aquatic environments, including soils. The naviculoid genus Luticola is widespread in various habitats and accounts for 264 species that are only based on morphological and morphometric characteristics. These parameters can greatly vary during the life cycle, making the species very similar to each other and complicating their unambiguous identification. During a study on soil algal diversity in the Russian Far East (Jewish Autonomous Region), we isolated a strain of naviculoid diatom and examined it using an integrative approach (phylogenetic, morphological, ultrastructural data, and life cycle). Phylogenetic analyses, based on chloroplast rbcL gene data, showed affinity of the new strain with the genus Luticola. Our alga shares morphological features typical of the genus members but differs from them by having valves with a larger width and hook-shaped external proximal raphe ends deflected to the side opposite the stigma. It was revealed that the strain reproduces via two types of sexual reproduction-isogamy and cis-anisogamy. Based on these phenotypic traits, we described the new isolate as Luticola tenera sp. nov.
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Due to the scarcity of air temperature (Ta) observations, urban heat studies often rely on satellite-derived Land Surface Temperature (LST) to characterise the near-surface thermal environment. However, there remains a lack of a quantitative understanding on how LST differs from Ta within urban areas and what are the controlling factors of their interaction. We use crowdsourced air temperature measurements in Sydney, Australia, combined with urban landscape data, Local Climate Zones (LCZ), high-resolution satellite imagery, and machine learning to explore the influence of urban form and fabric on the interaction between Ta and LST. Results show that LST and Ta have distinct spatiotemporal characteristics, and their relationship differs by season, ecological infrastructure, and building morphology. We found greater seasonal variability in LST compared to Ta, along with more pronounced intra-urban spatial variability in LST, particularly in warmer seasons. We also observed a greater temperature difference between LST and Ta in the built environment compared to the natural LCZs, especially during warm days. Natural LCZs (areas with mostly dense and scattered trees) showed stronger LST-Ta relationships compared to built areas. In particular, we observe that built areas with higher building density (where the heat vulnerability is likely more pronounced) show insignificant or negative relationships between LST- Ta in summer. Our results also indicate that surface cover, distance from the ocean, and seasonality significantly influence the distribution of hot and cold spots for LST and Ta. The spatial distribution for Ta hot spots does not always overlap with LST. We find that relying solely on LST as a direct proxy for the urban thermal environment is inappropriate, particularly in densely built-up areas and during warm seasons. These findings provide new perspectives on the relationship between surface and canopy temperatures and how these relate to urban form and fabric.
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Green vegetation may protect against heat-related death by improving thermal comfort. Few studies have investigated associations of green vegetation with heat-related mortality in Latin America or whether associations are modified by the spatial configuration of green vegetation. We used data from 323 Latin American cities and meta-regression models to estimate associations between city-level greenness, quantified using population-weighted normalized difference vegetation index values and modeled as three-level categorical terms, and excess deaths from heat (heat excess death fractions [heat EDFs]). Models were adjusted for city-level fine particulate matter concentration (PM2.5), social environment, and country group. In addition to estimating overall associations, we derived estimates of association stratified by green space clustering by including an interaction term between a green space clustering measure (dichotomized at the median of the distribution) and the three-level greenness variable. We stratified analyses by climate zone (arid vs. temperate and tropical combined). Among the 79 arid climate zone cities, those with moderate and high greenness levels had modestly lower heat EDFs compared to cities with the lowest greenness, although protective associations were more substantial in cities with moderate versus high greenness levels and confidence intervals (CI) crossed the null (Beta: -0.41, 95% CI: -1.06, 0.25; Beta -0.23, 95% CI: -0.95, 0.49, respectively). In 244 non-arid climate zone cities, associations were approximately null. We did not observe evidence of effect modification by green space clustering. Our results suggest that greenness may offer modest protection against heat-related mortality in arid climate zone Latin American cities.
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Temperatura Alta , Parques Recreativos , Cidades , América Latina/epidemiologia , Clima DesérticoRESUMO
Against the backdrop of global warming, rapid urbanization has caused the aggregation of urban building spaces and the heat island effect is becoming increasingly serious, hindering sustainable urban development. In order to investigate the potential and methods of green roofs in different types of neighborhoods to mitigate the urban heat island effect, this study used multivariate data for surface temperature inversion and local climate zone (LCZ), and the potential of green roofs to reduce the heat island effect was evaluated by combining LCZ zoning and ENVI-met prediction model. Finally, a multi-scenario analysis with economic factors was conducted to derive the optimal implementation path for green roofs. The results show that in LCZs 1-9, the green roof can reduce the daytime average air temperature by a maximum of 0.41 °C for 0.5 m of the LCZ8 roof and 0.37 °C for 1.2 m of the LCZ6 pedestrian. Based on the surface cooling efficiency of LCZ green roofs get the best green roof construction order: LCZ3, LCZ6, LCZ8 > LCZ2, LCZ5, LCZ7 > LCZ1, LCZ4, LCZ9. The construction of green roofs for the heat island areas within the fifth ring road of Beijing can reduce the area of high-temperature and sub-high-temperature zones by 52.55% and 29.17%, respectively, compared with the area without green roof construction. The study clarifies the technical methodology system of cooling efficiency of green roofs in different types of neighborhoods and the reduction of the urban-scale heat island effect, which provides a reference for the planning of green roofs for urban buildings.