85 research outputs found
Результаты мониторинга аэрозольной составляющей атмосферы в средних и высоких широтах и над акваторией Мирового океана
The article analyzes the observation data for the total optical thickness of the atmosphere at mid-latitude stations of the background air pollution monitoring on the territory of the Russian Federation for more than 40 years. The obtained results are compared with similar results in Northern and Southern Polar regions.The data of direct spectral observations of the aerosol optical thickness at the AERONET stations located in high and middle latitudes, as well as the spectral observational data over the Atlantic and Southern oceans collected during the voyages of research vessels to Antarctic and back, have been also drawn to the consideration. The analysis of observational data collected in such diverse conditions, allows evaluating the specificity and dynamics of aerosol pollution in various regions of the planet.В статье анализируются данные наблюдений за интегральной оптической толщиной атмосферы на среднеширотных станциях фонового мониторинга загрязнения атмосферы на территории Российской Федерации за более чем 40-летний период; данные спектральных фотометрических наблюдений за аэрозольной оптической толщиной на станциях международной сети AERONET, расположенных в высоких и средних широтах; данные спектральных фотометрических наблюдений в Атлантическом и Южном океанах, накопленные во время рейсов научно-экспедиционных судов в Антарктиду и обратно. Сопоставлены друг с другом результаты одних и тех же видов наблюдений в средних широтах и в северной и южной полярных областях. Анализ материалов наблюдений, полученных в таких разнообразных условиях, позволил оценить специфику и динамику изменений аэрозольного загрязнения в различных регионах планеты
База данных часовых и суточных сумм суммарной радиации на российских антарктических станциях: анализ изменения суммарной радиации за весь период наблюдений в Антарктиде
Given the significant changes in the climate on the planet as a whole, databases and archives of data on the main climate-forming characteristics of the atmosphere, collected over long periods of time in various regions of the globe and, in particular, in the polar regions, acquire a special role. Total solar radiation is one of the most important parameters affecting the energy balance of the Earth-atmosphere system. We have created a database (DB) of hourly and daily sums of total radiation (Q) at the Russian Antarctic stations, designed to study the radiation regime of the Antarctic, from the beginning of actinometric observations to 2019. The information presented in the database was collected at five Antarctic stations — Bellingshausen, Vostok Mirny, Novolazarevskaya and Progress. The database has undergone a state registration procedure and is registered under No. 2020621401. The article gives a description of the structure of the DB and presents detailed information for each station. To provide an example of how database information can be used, characteristics of the total radiation in different parts of the Antarctic continent are obtained. Thus, it is found that the average monthly amounts of Q in the continental part of Antarctica on the high plateau (Vostok station) in conditions of minimal cloudiness and high transparency during the Antarctic summer are maximum and average 1240 MJ/m2. At the same time, at the tip of the Antarctic Peninsula (Bellingshausen station) during the same period, the average monthly amounts of Q due to the almost constantly present cloud cover do not exceed 570 MJ/m2. In the coastal areas at the three remaining stations, the average monthly amounts of total radiation range from 908 MJ/m2 (Progress) to 950 MJ/m2 (Mirny). Estimates of variability characteristics of daily, monthly, and annual sums of total radiation at all the five stations for the entire observation period up to 2019 were also obtained. The absence of statistically significant long-term trends in the annual and monthly sums of total radiation at all the stations under consideration was noted. The results of their analysis indicate that there are no significant changes in the inflow of total solar radiation to the Antarctic surface over more than sixty years of actinometric observations.С учетом ощутимых изменений климата на планете в целом, особую роль приобретают базы и архивы данных основных климатообразующих характеристик атмосферы, собранных за длительные периоды времени в различных районах земного шара и, в частности, в полярных областях. Суммарная солнечная радиация входит в число важнейших параметров, влияющих на энергетический баланс системы Земля — атмосфера. В статье приведено описание созданной базы данных (БД) часовых и суточных сумм суммарной радиации на российских станциях Антарктиды. БД предназначена для исследования радиационного режима Антарктики с начала актинометрических наблюдений и до настоящего времени. База данных прошла процедуру государственной регистрации и зарегистрирована под № 2020621401. На основе содержащейся в ней информации были получены оценки характеристик изменчивости суточных, месячных и годовых сумм суммарной радиации на станциях Беллинсгаузен, Восток, Мирный, Новолазаревская и Прогресс за весь период наблюдений по 2019 г. Результаты их анализа свидетельствуют об отсутствии существенных изменений в поступлении суммарной солнечной радиации на антарктическую поверхность за более чем шестидесятилетний период актинометрических наблюдений
Многолетняя изменчивость годовых сумм суммарной и поглощенной солнечной радиации в Арктике
Variability of total (Q) and absorbed (Q – R) radiation after the year 2000 at some Russian Arctic stations in comparison with the long-term variability of these characteristics since the beginning of observations and until 1992 was investigated. As estimating parameters, the normalized by multiyear averages for 1961–1990 of anomalies of annual sums of total and absorbed radiation were chosen. We have analyzed the variability of total cloudiness and integral optical thickness characterizing transparency of the atmosphere as the factors producing the largest influence on total radiation incoming to the land surface. The integral optical thickness of the atmosphere in the Arctic after 2000 was most likely determined by specifics of air pollutants coming to the Arctic atmosphere and was significantly higher in the western Arctic area, than in the eastern one. After 2000 practically at all stations considered, the income of total radiation appeared to be below the multiyear average. Significant by the absolute value, but different by the sign, changes of absorbed radiation were recorded. The long-term periods of decrease and the subsequent increase of the incoming solar radiation observed at the European stations and called as “global dimming and global brightening” were not revealed at the Russian Arctic actinometric stations.Исследована изменчивость суммарной (Q) и поглощенной (Q – R) радиации после 2000 г. по данным отдельных арктических станций в сравнении с многолетней изменчивостью этих характеристик с начала наблюдений и по 1992 г. В качестве оценочных параметров выбраны нормированные на многолетние средние за 1961–1990 гг. значения аномалий годовых сумм суммарной и поглощенной радиации. Проанализирована изменчивость общей облачности и интегральной оптической толщины, характеризующей прозрачность атмосферы, как факторов, оказывающих наибольшее влияние на поступление суммарной радиации. Интегральная оптическая толщина атмосферы в Арктике после 2000 г., скорее всего, определялась спецификой поступления загрязняющих веществ в арктическую атмосферу и существенно выше в западном арктическом районе, нежели в восточном. После 2000 г. практически на всех рассматриваемых станциях приход суммарной радиации оказался ниже многолетней нормы. Зафиксированы значительные по абсолютной величине, но неодинаковые по знаку изменения поглощенной радиации. Длительных периодов уменьшения и последующего увеличения приходящей солнечной радиации, наблюдавшихся на европейских станциях и названных глобальным помутнением и просветлением атмосферы (“global dimming and global brightening”), на российских арктических актинометрических станциях не обнаружено
Co-Transport of Polycyclic Aromatic Hydrocarbons by Motile Microorganisms Leads to Enhanced Mass Transfer under Diffusive Conditions.
The
environmental chemodynamics of hydrophobic organic chemicals
(HOCs) are often rate-limited by diffusion in stagnant boundary layers.
This study investigated whether motile microorganisms can act as microbial
carriers that enhance mass transfer of HOCs through diffusive boundary
layers. A new experimental system was developed that allows (1) generation
of concentration gradients of HOCs under the microscope, (2) exposure
and direct observation of microorganisms in such gradients, and (3)
quantification of HOC mass transfer. Silicone O-rings were integrated
into a Dunn chemotaxis chamber to serve as sink and source for polycyclic
aromatic hydrocarbons (PAHs). This resulted in stable concentration
gradients in water (>24 h). Adding the model organism <i>Tetrahymena
pyriformis</i> to the experimental system enhanced PAH mass transfer
up to hundred-fold (benzo[a]pyrene). Increasing mass transfer enhancement
with hydrophobicity indicated PAH co-transport with the motile organisms.
Fluorescence microscopy confirmed such transport. The effective diffusivity
of <i>T. pyriformis</i>, determined by video imaging microscopy,
was found to exceed molecular diffusivities of the PAHs up to four-fold.
Cell-bound PAH fractions were determined to range from 28% (naphthalene)
to 92% (pyrene). Motile microorganisms can therefore function as effective
carriers for HOCs under diffusive conditions and might significantly
enhance mobility and availability of HOCs
Dimensions of invasiveness: Links between local abundance, geographic range size, and habitat breadth in Europe's alien and native floras
Understanding drivers of success for alien species can inform on potential future invasions. Recent conceptual advances highlight that species may achieve invasiveness via performance along at least three distinct dimensions: 1) local abundance, 2) geographic range size, and 3) habitat breadth in naturalized distributions. Associations among these dimensions and the factors that determine success in each have yet to be assessed at large geographic scales. Here, we combine data from over one million vegetation plots covering the extent of Europe and its habitat diversity with databases on species' distributions, traits, and historical origins to provide a comprehensive assessment of invasiveness dimensions for the European alien seed plant flora. Invasiveness dimensions are linked in alien distributions, leading to a continuum from overall poor invaders to super invaders - abundant, widespread aliens that invade diverse habitats. This pattern echoes relationships among analogous dimensions measured for native European species. Success along invasiveness dimensions was associated with details of alien species' introduction histories: earlier introduction dates were positively associated with all three dimensions, and consistent with theory-based expectations, species originating from other continents, particularly acquisitive growth strategists, were among the most successful invaders in Europe. Despite general correlations among invasiveness dimensions, we identified habitats and traits associated with atypical patterns of success in only one or two dimensions - for example, the role of disturbed habitats in facilitating widespread specialists. We conclude that considering invasiveness within a multidimensional framework can provide insights into invasion processes while also informing general understanding of the dynamics of species distributions.Deutsche Forschungsgemeinschaft (264740629)
Grantová Agentura České Republiky (19-28491X)
Grantová Agentura České Republiky (19-28807X)
Grantová Agentura České Republiky (RVO 67985939)
Austrian Science Fund (I 2086 - B29)
Bundesministerium für Bildung und Forschung (01LC1807A)
Eusko Jaurlaritza (IT299-10)
National Research Foundation of Korea (2018R1C1B6005351)
University of Latvia (AAp2016/B041//Zd2016/AZ03)
Villum Fonden (16549
Advancing the use of passive sampling in risk assessment and management of contaminated sediments: Results of an international passive sampling inter-laboratory comparison
This work presents the results of an international interlaboratory comparison on ex situ passive sampling in sediments. The main objectives were to map the state of the science in passively sampling sediments, identify sources of variability, provide recommendations and practical guidance for standardized passive sampling, and advance the use of passive sampling in regulatory decision making by increasing confidence in the use of the technique. The study was performed by a consortium of 11 laboratories and included experiments with 14 passive sampling formats on 3 sediments for 25 target chemicals (PAHs and PCBs). The resulting overall interlaboratory variability was large (a factor of ∼10), but standardization of methods halved this variability. The remaining variability was primarily due to factors not related to passive sampling itself, i.e., sediment heterogeneity and analytical chemistry. Excluding the latter source of variability, by performing all analyses in one laboratory, showed that passive sampling results can have a high precision and a very low intermethod variability
Ellenberg-type indicator values for European vascular plant species
Aims: Ellenberg-type indicator values are expert-based rankings of plant species according to their ecological optima on main environmental gradients. Here we extend the indicator-value system proposed by Heinz Ellenberg and co-authors for Central Europe by incorporating other systems of Ellenberg-type indicator values (i.e., those using scales compatible with Ellenberg values) developed for other European regions. Our aim is to create a harmonized data set of Ellenberg-type indicator values applicable at the European scale. Methods: We collected European data sets of indicator values for vascular plants and selected 13 data sets that used the nine-, ten- or twelve-degree scales defined by Ellenberg for light, temperature, moisture, reaction, nutrients and salinity. We compared these values with the original Ellenberg values and used those that showed consistent trends in regression slope and coefficient of determination. We calculated the average value for each combination of species and indicator values from these data sets. Based on species’ co-occurrences in European vegetation plots, we also calculated new values for species that were not assigned an indicator value. Results: We provide a new data set of Ellenberg-type indicator values for 8908 European vascular plant species (8168 for light, 7400 for temperature, 8030 for moisture, 7282 for reaction, 7193 for nutrients, and 7507 for salinity), of which 398 species have been newly assigned to at least one indicator value. Conclusions: The newly introduced indicator values are compatible with the original Ellenberg values. They can be used for large-scale studies of the European flora and vegetation or for gap-filling in regional data sets. The European indicator values and the original and taxonomically harmonized regional data sets of Ellenberg-type indicator values are available in the Supporting Information and the Zenodo repository
Genetic diversity and population structure of Polistes nimpha based on DNA microsatellite markers
Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts
Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).
Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold.
The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates.
Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants.
The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances
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