Cold Months Research Articles

Methodological approach to determining the area of air recycling on metro lines with double track tunnels

The article discusses the issues of operating existing metro lines with double-track tunnels. Significant differences between average annual, average monthly and extreme values of outdoor air temperature affecting the thermodynamic and thermophysical parameters of the mine atmosphere of subway tunnels, both in Russia and abroad, are analyzed. The results of a comprehensive analysis of the conditions that determine the temperature regime of the lines of double-track tunnels are presented. Air recirculation in the tunnels has been determined considering climatic conditions. Engineering and technical calculations have been carried out in metro tunnels when the seasonal periods of their operation change. Each of these periods is characterized by its own temperature, for example, for the winter period these are: average winter temperatures, temperatures of the coldest month, the coldest five-day period. The obtained results of the research work will make it possible to select the amount of air for each specific variant of the year, which will ensure, during the operation of this kind of metro lines, the standard thermodynamic parameters of the air environment, both in underground stations and in metro tunnels, and possibly lead to a positive economic effect.

Effective methods of agricultural use of light colored gray soils distributed in Kuva hill

Fergana Valley is a tectonic depression surrounded by mountains, and its appearance is in the form of an ellipse. Its length from west to east is 300 km equal to 50 meters from south to north. 70 km The height of the valley reaches from sea level in the west to . in the 250 мeast 1000 м. The height of the surrounding high mountains of Central Ferghana is 2000 - 4000 m and more. Such a sharp geomorphological structure determines the specific characteristics of the valley’s climate. The western and central parts of the Fergana valley (up to the Margilan oasis) belong to the desert region, and the eastern part to the semi-desert region. The climatic conditions of the desert part are described by the meteorological stations “Ko’kan”, “Ultarma” and “Namangan”, and the semi-desert part by the data of the weather stations “Fergana”, “Nasriddinbek” and “Fedchenko”. In the western and northern regions of the valley, the long-term average air temperature is +13+13.5 0 C. The coldest month of the year is January, its average temperature is -2.1-2.40 C. The period with the highest temperature is July, and the average temperature is around +24.8+27.6 0 C. ( Tables 1-2 ). The minimum temperature is -27-29 0 C, the maximum temperature is +42+46 0 C. We present the detail of the morphology of the 1st soil cross-section, trying to reveal the specific characteristics of the pale gray gypsum soils in the Kuva hills. The soils formed in the Kuva hills, where we conducted research, are the result of the long-term development of the area. Kuva mountain range is located 500-600m above sea level. The pale gray soils distributed in these areas are composed of stony rocks formed on loess and loess sand. At the same time, it appeared on coarse, gravelly-soft rock formations and gravels, on top of which a thin skeleton of sand and silt is covered.

Indoor environmental quality in an Apulian kindergarten

Indoor environmental quality (IEQ) in school buildings is crucial for the health and well-being of students, educators, and staff. Poor air quality and inadequate thermal conditions compromise students’ comfort and can lead to potential long-term health issues. Since children’s comfort differs from adults’, it is important to consider surveys on IEQ in school buildings. For this reason, this paper focuses on air quality and thermal comfort in kindergartens in Italy. An IEQ monitoring campaign was conducted within a kindergarten, with data used for thermal comfort and IAQ analyses, including CO2 levels generated by occupants and thermal discomforting hours. The simulations of carbon dioxide levels showed that the amount of CO2 accumulated in the classrooms exceeds the threshold recommended by ASHRAE guidelines. During the winter seasons, CO2 levels are significantly higher than those accumulated in summer due to the limited ventilation practiced during the colder months. Moreover, thermal comfort analyses indicate that the summer season can be problematic due to overheating: 42% of the occupied hours during the monitoring period exceeded the temperature threshold, causing thermal discomfort for the occupants. The winter thermal comfort analyses demonstrated that heating systems are essential to maintain temperatures within comfort thresholds.

The potential habitat of Angelica dahurica in China under climate change scenario predicted by Maxent model.

Since the 20th century, global climate has been recognized as the most important environmental factor affecting the distribution of plants. Angelica dahurica (A. dahurica) has been in great demand as a medicinal herb and flavoring, but the lack of seed sources has hindered its development. In this study, we utilized the Maxent model combined with Geographic Information System (GIS) to predict the potential habitat of A. dahurica in China based on its geographical distribution and 22 environmental factors. This prediction will serve as a valuable reference for the utilization and conservation of A. dahurica resources.The results indicated that: (1) the Maxent model exhibited high accuracy in predicting the potential habitat area of A. dahurica, with a mean value of the area under the ROC curve (AUC) at 0.879 and a TSS value above 0.6; (2) The five environmental variables with significant effects were bio6 (Min temperature of the coldest month), bio12 (Annual Precipitation), bio17 (Precipitation of Driest Quarter), elevation, and slope, contributing to a cumulative total of 89.6%. Suitable habitats for A. dahurica were identified in provinces such as Yunnan, Guizhou, Guangxi, Sichuan, Hunan, and others. The total area of suitable habitat was projected to increase, with expansion primarily in middle and high latitudes, while areas of decrease were concentrated in lower latitudes. Under future climate change scenarios, the centers of mass of suitable areas for A. dahurica were predicted to shift towards higher latitudes in the 2050s and 2090s, particularly towards the North China Plain and Northeast Plain. Overall, it holds great significance to utilize the Maxent model to predict the development and utilization of A. dahurica germplasm resources in the context of climate change.

Epidemiological Study on Relationship Between Some of Demographic Characteristics and the Prevalence of Hydatid Cysts Disease in the Holy City of Karbala

Hydatid cyst or hydatidosis is one of the common diseases between humans and animals (zoonotic disease) and has a global spread. Due to the importance of the disease, we chose this topic to find out the epidemiological extent of the spread of the disease and its relationship to some demographic characteristics. Where statistical data was collected and analyzed for those with hydatid cysts who were treated with surgical intervention at Al-Hussein Teaching Hospital in the Holy Governorate of Karbala. The statistics included (the number of infected people - age - gender - months of infection - residential areas - multiplicity of infections - affected body parts). The total number of infected people was (40) for both sexes for the year (2022). There were (27) infected cases (67.5%) in females and (13) infected cases (32.5%) in males. Thus, the infection rate in females is higher than in males. The infection rate according to age was highest in the youth group (21-30) and the lowest in the very young and very old ages. The highest infection rate during the year was during June and September, while the lowest was in the cold months of December and January, in which no infection was recorded. The infection rate in rural areas (Al-Hindiyya and Al-Husseiniyah sectors) was higher than in city areas. As for multiple infections, the highest percentage is a single infection, and the most affected organ is the liver, then the abdominal cavity, while the least affected organ is the lung.

Particulate matter air pollution in the Republic of Slovenia and its national spatial emissions release

In this work, an impact of particulate matter (PM) on air pollution and its emissions released is investigated. Concentration levels of PM10 and PM2.5 in the Republic of Slovenia (RS) were analyzed on daily, weekly, monthly, quartile, and annual data and then compared. The study was conducted from January 1, 2020 to December 31, 2020 at two monitoring stations, so-called urban traffic and urban industrial. Obtained results showed that the highest concentrations of PM in air were during the cold months of the year when the temperatures are lower (< 6%). Results from heating seasons (from October 1, 2019 and March 31, 2020 and from October 1, 2020 to March 31, 2021) showed the highest concentration levels of PM10 between 9:00 and 14:00 and between 18:00 and 22:00, with highest concentrations recorded during the winter months (January and February). Additionally, emission building inventory was built based on PM10 and PM2.5 emissions released. The study includes yearly spatial building emissions release model considering currently installed high PM emitted stoves. The building model for the Republic of Slovenia has been developed by using 500 x 500 m model grid. Obtained results showed that changing currently low efficient appliance with advanced appliance would result in significant lower PM emissions released from building sector.

Effect of GnRH on the day of Insemination on Ovulatory Response in Crossbred Cows

The effect of gonadotropin releasing hormone (GnRH) analogue on the ovulatory response of oestrual follicle during cold and hotter months of the year was studied. A total of 120 crossbred cows brought for insemination with oestrus signs during colder months (December 2022 –January 2023; n=52) and hotter months (April – May 2023; n=68) to the Gynaecology Unit of Veterinary Clinical Complex, Veterinary College and Research Institute, Orathanadu were utilized for the study. Oestrus (Day 0) was confirmed by gynaeco-clinical and ultrasound examination and animals were inseminated with (n =33) or without (n = 87) GnRH (Buserelin acetate 10 mcg; im). The biometry of oestrual follicle (OF) and regressing corpus luteum (RCL) were measured ultrasonographically on Day 0 and the OF was observed every 24 hours until ovulation. The diameter of the OF on Day 0 was non-significantly (P > 0.05) larger during hotter months (12.19 ± 0.21 mm) than colder months (11.58 ± 0.32 mm). There were no significant (P > 0.05) differences in the diameter of RCL between the two periods (9.63 ± 0.21 and 9.56 ± 0.22 mm respectively). OFs were observed majorly in the right ovary during the hotter (60.76%) and colder (54.17%) months. Ovulations occurred on the mean days of 1.00 and 1.37 ± 0.18 in GnRH group during hotter (H-Gn) and colder months (C-Gn) respectively. The respective mean days in non-GnRH group were 1.14 ± 0.05 and 1.33 ± 0.08 during hotter (H-O) and colder months (C-O). In H-Gn group all the animals (100%) ovulated on Day 1, when compared to C-Gn animals (62.50%). On perusing the possible effect of RCL on ovulation, significantly increased percentages of ovulations were observed in OFs on the contralateral ovary to the ovary having the RCL in GnRH group and viceversa in non-GnRH group. It could be assumed that GnRH administration on the day of insemination may be beneficial during the hotter months of the year.

Circadian clock- and temperature-associated genes contribute to overall genomic differentiation along elevation in lichenized fungi.

Circadian regulation is linked to local environmental adaptation, and many species with broad climatic niches display variation in circadian genes. Here, we hypothesize that lichenizing fungi occupying different climate zones tune their metabolism to local environmental conditions with the help of their circadian systems. We study two species of the genus Umbilicaria occupying similar climatic niches (Mediterranean and the cold temperate) in different continents. Using homology to Neurospora crassa genes, we identify gene sets associated with circadian rhythms (11 core, 39 peripheral genes) as well as temperature response (37 genes). Nucleotide diversity of these genes is significantly correlated with mean annual temperature, minimum temperature of the coldest month and mean temperature of the coldest quarter. Furthermore, we identify altitudinal clines in allele frequencies in several non-synonymous substitutions in core clock components, for example, white collar-like, frh-like and various ccg-like genes. A dN/dS approach revealed a few significant peripheral clock- and temperature-associated genes (e.g. ras-1-like, gna-1-like) that may play a role in fine-tuning the circadian clock and temperature-response machinery. An analysis of allele frequency changes demonstrated the strongest evidence for differentiation above the genomic background in the clock-associated genes in U. pustulata. These results highlight the likely relevance of the circadian clock in environmental adaptation, particularly frost tolerance, of lichens. Whether or not the fungal clock modulates the symbiotic interaction within the lichen consortium remains to be investigated. We corroborate the finding of genetic variation in clock components along altitude-not only latitude-as has been reported in other species.

Effect of the thermal environment on mortality: analysis of longitudinal data from Cyprus (2009–2018)

Exposure to a suboptimal outdoor thermal environment is associated with increased morbidity and mortality. This study aimed to examine the effect of the thermal environment on all-cause mortality in Cyprus. Daily mortality data were obtained from 2009 to 2018. Hourly meteorological data were retrieved from the ERA5-Land reanalysis database and air pollutant concentrations were obtained from the official air quality network of the Republic of Cyprus. Air temperature (Tair), the physiologically equivalent temperature (PET), and the universal thermal climate index (UTCI) were used to assess the thermal environment. Associations of Tair, PET, and UTCI with daily mortality were examined using negative binomial regression while adjusting for air quality. Mortality in the cold period (December to March) increased by 3.3% for each 1 °C decrease in Tair and by up to 1.8% for each 1 °C decrease in PET and UTCI (p value < 0.001). In the warm period (April to November), a 1 °C increase in Tair or in PET and UTCI was associated with an increase in mortality of up to 1.4% and 1.1% (p value < 0.001), respectively. The effect (increase in mortality) was more pronounced when the analysis focused on winter (3.6% per 1 °C decrease in Tair, 2.4% per 1 °C decrease in PET, and 2% per 1 °C decrease in UTCI) and summer (4.1% per 1 °C increase in Tair, 2.4% per 1 °C increase in PET, and 1.2% per 1 °C increase in UTCI). Males in cold periods and the elderly (older than 64 years) were more vulnerable. Awareness about the effects of the thermal environment on mortality, including those during the cold months of the year, should be enhanced.

Testing the Suitability of Snow Depth in Winter Recreation Areas in Cities in the Republican Period with InSAR Technique: Abalı Ski Center Example

The Republican period is a period that coincides with the modernization process of Turkey, and the lifestyle in the cities has also changed significantly during this period. Winter recreation areas are the areas that people prefer to have fun, do sports and relax in the cold months. The Republic of Türkiye has a great importance in the tourism sector. In addition, the alternative tourism sector is developing rapidly and leading to different investments. Increasing winter recreation areas and facility investments in order to keep four seasons tourism alive with the advantage of climatic diversity is of great importance for alternative tourism. Different criteria such as slope, aspect, height, transportation, and sunshine duration are used to determine suitable areas for these investments. However, the most important suitability criterion is the snow factor. In order for the facilities to be established, the snow must be permanent and of a certain thickness in the winter season. In this study, the winter season (December-January-February) was examined temporally (2020-21-22), in the example of the Abalı Ski Center established in the republican period, and the average snow depth change in the area was determined by the InSAR (Interferometric Artificial Aperture Radar) technique. In addition, the accuracy of the results was tested with the real measurements of the 2021-22 winter season in the study area. The analysis conducted to assess the accuracy of Sentinel-1A C-band RADAR images by comparing snow depth data has yielded a high correlation value of 0.79, indicating a strong and consistent result. As a result, the importance of determining the snow factor both as a suitability criterion in determining the suitability of land use and the suitability of snow permanence in temporal change for establishment has been revealed.

Survey on Aculops lycopersici and operational factors potentially affecting successful pest management among 50 tomato producers in Germany

Aculops lycopersici (Acari: Eriophyoidea) is a pest in tomato cultivation worldwide. In recent years, the number of reports of A. lycopersici infestations in tomato have increased in Germany. In the first half of 2019, a survey of 50 tomato producing farms was conducted to assess the occurrence of A. lycopersici and the impact this pest has on tomato cultivation in Germany. The participating farms represented ~ 3.5% of the 1448 farms in Germany with protected tomato production in 2019. Total tomato production area considered in the survey was 131.8 ha which corresponds to ~ 34% of the 385.63 ha of protected tomato production area in Germany in this year. A. lycopersici presence was reported by 33 of the 50 surveyed farms, within the last 5 years. Amongst these 50 participants it was the pest with the highest relative importance in terms of plant protection effort exerted. A. lycopersici occurrence was reported more frequently from production systems with a higher intensification. For instance, heating in cold months and a larger production area were considered intensification factors in this study. However, due to autocorrelation between intensification factors it was not possible to link increased occurrence to specific factors. As the intensification factors favouring A. lycopersici occurrence are more prevalent in integrated production, those farms faced A. lycopersici occurrence more often than the organic growers in this study. Plant protection strategies often combine broad treatments of sulphur with local abamectin treatments, removal of infested plant material and the introduction of natural enemies.

Assessment of Radon and Naturally Occurring Radionuclides in the Vredefort Meteorite Crater in South Africa

The concentric impact rings of the Vredefort Crater contain rocks with elevated uranium concentrations resulting from the geological signature of a meteoric impact. The decay of this uranium was estimated to lead to elevated indoor radon concentrations in the Crater, but such a study has never been carried out. This study explores the relationship between the natural radionuclides found in the geology of the Vredefort Crater and indoor radon concentrations. This was achieved through soil sampling and radionuclide surveys conducted on three impact rings, supplemented by indoor radon measurements in dwellings found in the area. In situ measurements revealed that one impact ring had higher-than-average uranium concentrations at 50 Bq/kg. Surprisingly, the measured indoor radon levels were lower than expected (113 Bq/m3). These measurements were taken during the COVID-19 pandemic and colder months, conditions that would typically result in elevated indoor radon levels. Soil samples indicated uranium activity of 30 Bq/kg, comparable to the world average of 35 Bq/kg. However, defunct mine tunnels in the area exhibited elevated radon concentrations, averaging 364 Bq/m3. The disparity between expected and measured indoor radon levels was attributed to the composition of surficial deposits, bedrock, and architectural features of the dwellings preventing radon accumulation.

Impact of a small-scale solar park on temperature and vegetation parameters obtained from Landsat 8

The effects of photovoltaic solar parks on the local environment are a growing topic of interest, as more solar parks are installed worldwide. Most studies focus on large solar parks, as these usually have more availability for both in situ and remote sensing data. Here, remote sensing data of surface temperature and vegetation were used to assess the impact of a relatively small utility-scale solar park (46 MW) in Portugal, in a region with a Mediterranean climate. Results show that the impact translates into a seasonal pattern, with positive surface temperature anomalies during the colder months and negative ones during the summer, which overall reduces the amplitude of the seasonal cycle. Comparing the operational period of the solar park with the one before its installation yields an increase in surface temperature for the control area of 1.74 °C contrasting with a decrease of 0.23 °C in the solar park area, during summertime (JJA). For the winter months (DJF), surface temperature increased for the solar park and control areas, by 0.4 °C and 1.44 °C, respectively. The effect is similar but less pronounced for anomalies in the inferred air temperature. For vegetation, negative anomalies in winter and little to no change during hotter months are observed.

Fine particulate matter (PM2.5) exposure assessment among active daily commuters to induce behaviour change to reduce air pollution

Fine particulate matter (PM2.5), a detrimental urban air pollutant primarily emitted by traffic and biomass burning, poses disproportionately significant health risks at relatively limited exposure during commuting. Previous studies have mainly focused on fixed locations when assessing PM2.5 exposure, while neglecting pedestrians and cyclists, who often experience higher pollution levels. In response, this research aimed to independently validate the effectiveness of bicycle-mounted low-cost sensors (LCS) adopted by citizens, evaluate temporal and spatial PM2.5 exposure, and assess associated health risks in Ljubljana, Slovenia. The LCS quality assurance results, verified by co-location field tests by air quality monitoring stations (AQMS), showed comparable outcomes with an average percentage difference of 21.29 %, attributed to humidity-induced nucleation effects. The colder months exhibited the highest air pollution levels (μ = 32.31 μg/m3) due to frequent thermal inversions and weak wind circulation, hindering vertical air mixing and the adequate dispersion of pollutants. Additionally, PM2.5 levels in all sampling periods were lowest in the afternoon (μ = 12.09 μg/m3) and highest during the night (μ = 61.00 μg/m3) when the planetary boundary layer thins, leading to the trapping of pollutants near the surface, thus significantly affecting diurnal and seasonal patterns. Analysis of exposure factors revealed that cyclists were approximately three times more exposed than pedestrians. However, the toxicological risk assessment indicated a minimal potential risk of PM2.5 exposure. The collaborative integration of data from official AQMS and LCS can enhance evidence-based policy-making processes and facilitates the realignment of effective regulatory frameworks to reduce urban air pollution.

Efecto del cambio climático en la distribución de las especies de clima templado en Oaxaca, México

Background: Climate change is becoming more evident, and distribution models are useful tools to predict the effect it might cause on biodiversity.&#x0D; Hypotheses: Under climate change scenarios, temperate forests species of the genus Pinus and Quercus will undergo reductions in their distribution area and changes in their spatial pattern.&#x0D; Studied species: Arbutus xalapensis, Clethra mexicana, Pinus devoniana, Pinus oocarpa, Pinus teocote, Quercus acutifolia, Quercus castanea, Quercus crassifolia, Quercus elliptica, Quercus magnoliifolia and Quercus rugosa.&#x0D; Study site: Oaxaca&#x0D; Methods: Two scenarios were constructed, an optimistic one (SSP-1 and RCP 2-6) and a pessimistic one (SSP-5 and RCP 8.5) for the years 2030 and 2090. A total of 1,383 records and eight bioclimatic variables were used, along with seven learning algorithms, evaluated using ROC and TSS metrics.&#x0D; Results: An ensemble model was obtained, in which the most important contributing variables were precipitation of the wettest quarter, mean annual temperature, minimum temperature of the coldest month and annual temperature range. The species that showed the highest ROC values were Clethra mexicana (0.91) and Arbutus xalapensis (0.89) with TSS values of 0.68 and 0.60, respectively.&#x0D; Conclusions: Regardless of the scenario, by the year 2090 all species of Pinus and Quercus will reduce their potential distribution. Therefore, it is urgent to establish conservation policies.

The adaptive skill of pest dysdercus koenigii fabricius (hemiptera, pyrrhocoridae),and their destruction on the plant Abelmoschus esculenta, at Ramgarh (Jharkhand, India).

The insect Dysdercus koenigii Fabricus (Hymenoptera,pyrrhocoridae) is a polyphagus serious vegetable pest. Its adaptation with change in climatic temperature and humidity makes it the omnipresent, it is commonly called as Red Cotton bug. Adults have more climatic tolerance than nymphs and eggs. In extreme cold the eggs hatched to nymph and nymph to adult in short duration,during this period adult hides under the old fallen decaying leaves on the soil, in the cracks or crevices. In the spring the female lays eggs on the moist ground under the old decaying leaves, in the cracks or in the crevices. The incubation period for eggs completed and tiny nymphs appear, after 5 moults nymph transform into adults. In hot season the life cycle was variable, in the scarcity of host plant pest migrate to or bridging to other cultivated plant and continue its life cycle but its most likely host plant is cotton plant. The experimental place Ramgarh is a district town located at atlatitude: 23.380 N and longitude 85.340E. Moderate temperature, more humidity and dense greenary make it one of the most attractive district. Nature puts all the workmanship to create this place and reinforced all its beauty to it. It is surrounded on three sides by hills and open at one side by planes .The slop of the hills, variety of soils, plants and animals make it a natural resource of biodiversity. It is a niche for various kinds of animal and insect (Upadhyay2023). The experimental pest Dysdercus koenigii. Fabricius (Hemiptera, pyrrhocoridae) was also observed in the crop field of Ramgarh. The farmers cultivate vegetable plant Abelmos chus esculentus in mass level and experimental pest like to feeds the soft leaves and pods of host plants decline the quality of product and reduce quantity. During extreme cold months egg and nymph transform into adult is adapted to tolerate cold better and spend their life to enter under the decaying fallen leaves ,in the cracks or in the crevices .In extreme hot season its life cycle become variable, rising in temperature and humidity varies its life cycle. Prevention from this bug is very difficult; no natural enemies are better known, but control of pest population by some synthetic chemicals are advised to the farmers to spray. Endosulphan 2% dust, Malathion and Fenitrothion are widely used insecticides to control the bug population. . KEYWORDS :Nature, Biodiversity, adaptation, variable, quantity population, synthetic chemical.

Application of steel fibre reinforced concrete for ensuring concrete frost resistance of transport structures on regional and inter-municipal highways of Khabarovsk Krai motor roads of Khabarovsk region

In this paper the authors present the research results into the application of steel fibre reinforced concrete for ensuring frost resistance and durability of transport structures on regional and intermunicipal highways of Khabarovsk Krai. The object of the present research was concrete of reinforced concrete round culverts rings 3D 15.35 (GOST 24547-2016, OST 35-27.0-85), produced at the industrial and production enterprise CJSC «Khabarovsk Avtomost» in Khabarovsk. Pipe blocks are designed for use in the construction of culverts under motorway bankets (including industrial roads), built in areas with seismicity up to nine points in all climatic zones on periodically operating watercourses in the absence of ice. Concrete class on strength of compression is accepted by designers — B25, according to SP 35.13330.2011 (new edition of SNiP 2.05.03-84*) the grade of concrete matrix on frost resistance was assigned taking into account the average temperature of the coldest month in the area where the construction is planned. In the conditions of the region under consideration there are natural and climatic conditions for assigning the grade of frost resistance F300. One of the tasks solved by the authors was the selection of concrete composition taking into account qualitative features of initial local materials properties and the use of dispersed reinforcement, providing the concrete of transport structures with a given strength, frost resistance and water resistance. The authors have presented the strength determination results, frost resistance and waterproofing of steel fibre reinforced concrete with «PFM-NLK» and steel fibre for reinforced concrete round culverts rings 3D 15.35. The experimental studies results allowed to justify the use of steel fibre reinforced concrete for ensuring frost transport structures resistance on regional and intermunicipal highways of Khabarovsk Krai, which is a determining factor for increasing their durability. The obtained results are applied for the standard of the organisation development — CJSC «Khabarovsk Avtomost» — 002-2015 «Increase of frost resistance of concrete of transport constructions on regional and intermunicipal highways of Khabarovsk region».

Five Years of Accurate PM2.5 Measurements Demonstrate the Value of Low-Cost PurpleAir Monitors in Areas Affected by Woodsmoke

Low-cost optical sensors are used in many countries to monitor fine particulate (PM2.5) air pollution, especially in cities and towns with large spatial and temporal variation due to woodsmoke pollution. Previous peer-reviewed research derived calibration equations for PurpleAir (PA) sensors by co-locating PA units at a government regulatory air pollution monitoring site in Armidale, NSW, Australia, a town where woodsmoke is the main source of PM2.5 pollution. The calibrations enabled the PA sensors to provide accurate estimates of PM2.5 that were almost identical to those from the NSW Government reference equipment and allowed the high levels of wintertime PM2.5 pollution and the substantial spatial and temporal variation from wood heaters to be quantified, as well as the estimated costs of premature mortality exceeding $10,000 per wood heater per year. This follow-up study evaluates eight PA sensors co-located at the same government site to check their accuracy over the following four years, using either the original calibrations, the default woodsmoke equation on the PA website for uncalibrated sensors, or the ALT-34 conversion equation (see text). Minimal calibration drift was observed, with year-round correlations, r = 0.98 ± 0.01, and root mean square error (RMSE) = 2.0 μg/m3 for daily average PA PM2.5 vs. reference equipment. The utitilty of the PA sensors without prior calibration at locations affected by woodsmoke was also demonstrated by the year-round correlations of 0.94 and low RMSE between PA (woodsmoke and ALT-34 conversions) and reference PM2.5 at the NSW Government monitoring sites in Orange and Gunnedah. To ensure the reliability of the PA data, basic quality checks are recommended, including the agreement of the two laser sensors in each PA unit and removing any transient spikes affecting only one sensor. In Armidale, from 2019 to 2022, the continuing high spatial variation in the PM2.5 levels observed during the colder months was many times higher than any discrepancies between the PA and reference measurements. Particularly unhealthy PM2.5 levels were noted in southern and eastern central Armidale. The measurements inside two older weatherboard houses in Armidale showed that high outdoor pollution resulted in high pollution inside the houses within 1–2 h. Daily average PM2.5 concentrations available on the PA website allow air pollution at different sites across regions (and countries) to be compared. Such comparisons revealed major elevations in PA PM2.5 at Gunnedah, Orange, Monash (Australian Capital Territory), and Christchurch (New Zealand) during the wood heating season. The data for Gunnedah and Muswellbrook suggest a slight underestimation of PM2.5 at other times of the year when there are proportionately more dust and other larger particles. A network of appropriately calibrated PA sensors can provide valuable information on the spatial and temporal variation in the air pollution that can be used to identify pollution hotspots, improve estimates of population exposure and health costs, and inform public policy.

Spatiotemporal Variability of Urban Air Pollution in Bucharest City

Urban air pollution is one of the major challenges that cities around the world face. Particulate matter (PM), nitrogen dioxide (NO2), volatile organic compounds (VOCs), and other pollutants are many times over the recommended airborne exposure, generating a strong impact on human health and city well-being. Considering Bucharest as a case study, this study aimed to investigate the patterns of particulate matter and nitrogen dioxide concentrations. Multiyear data from the Romanian National Air Quality Monitoring Network were used to investigate spatial and temporal variability. All air pollutants presented a typical bimodal trend during the day, with specific double peaks corresponding to the morning rush hours and nighttime. Spatial variability in NO2 concentrations was observed, with almost double the concentration values in the city center during midday compared with those for the background and industrial areas. A weekly pattern of PM was noticed, with lower concentrations during the weekends in comparison with those during weekdays, more pronounced in the case of PM10 compared with the case of PM2.5. The fine particle fraction presented monthly and seasonal variability, with higher levels during the cold months compared with the warm months, mainly corresponding to the increased household heating. The estimated proportion of mortality attributable to annual exposure to an air PM2.5 above 5 μg/m3 in Bucharest ranged between 7.55% and 8.26%, with the maximum from 2021. By contrast, the estimated proportion of mortality attributable to PM10 and NO2 above 10 μg/m3 was significantly lower, with values around 4%. The results are useful in supporting environmental planning measures to decrease urban air pollution.

Enhancing Propagation of Orostachys spp. Offsets through Exogenous GA3 Application

Orostachys spp., considered economically important succulent plants for both the medicinal and ornamental plant industries, are known to exhibit slow growth in their offsets during the long, cold winter months. Due to the slow growth, this study investigated the application of gibberellic acid (GA3) and determined the optimal GA3 concentration (control, 200 mg·L−1, 400 mg·L−1, and 600 mg·L−1) for promoting the propagation of three Orostachys species (i.e., O. fimbriata, O. japonica, and O. minuta), as well as its impact on their growth and development. According to our study findings, O. fimbrata and O. minuta influenced by GA3 exhibited higher survival rates (7–38%) and offset growth rates (3–87%) compared to the control. Similarly, its application resulted in significant shoot and root development, along with increased moisture content for the majority of the species. The results of this research demonstrate the potential and practical applications of using GA3 to increase the propagation and growth of Orostachys spp. during cold conditions for year-round propagation of these succulent plants, which could have ecological and horticultural significance for related species as well as other vegetatively propagated crops.