Repurposing of brownfield sites is often promoted, because it is perceived that protecting the “green belt” limits damage to biodiversity; yet brownfield sites provide scarce habitats with limited ...disturbance, so conversely are also perceived to be ecologically valuable. Combining data from three national-scale UK biological monitoring schemes with location data on historical landfill sites, we show that species richness is positively associated with both the presence and increasing area of ex-landfill sites for birds, plants and several insect taxa. Assemblage rarity of birds is also positively associated with presence of ex-landfill sites. Species richness associated with ex-landfill sites declined over time for birds and insects but increased over time for plants. These findings suggest that development of brownfield sites may have unintended negative consequences for biodiversity, and imply that to minimise loss of biodiversity, brownfield site repurposing could be targeted towards smaller sites, or sites in areas with a high density of other brownfield sites.
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•Species richness of birds, plants and insects is higher in landscapes containing ex-landfill sites.•Birds also have higher assemblage rarity in landscapes containing ex-landfill sites.•For birds, plants and insects, species richness increases with increasing area of ex-landfill sites.•For birds and insects, species richness declines over time after landfill site closure.•For plants, species richness increases over time after landfill site closure.
Deposits of fly ash and other coal combustion wastes are common remnants of the energy industry. Despite their environmental risks from heavy metals and trace elements, they have been revealed as ...refuges for threatened terrestrial biodiversity. Surprisingly, freshwater biodiversity of fly ash sedimentation lagoons remains unknown despite such lack of knowledge strongly limits the efficient restoration of fly ash deposits. We bring the first comprehensive survey of freshwater biodiversity, including nekton, benthos, zooplankton, phytoplankton, and macrophytes, in fly ash lagoons across industrial regions of the Czech Republic. To assess their conservation potential, we compared their biodiversity with abandoned post-mining ponds, the known strongholds of endangered aquatic species in the region with a shortage of natural ponds. Of 28 recorded threatened species, 15 occurred in the studied fly ash lagoons, some of which were less abundant or even absent in the post-mining ponds. These are often species of nutrient-poor, fishless waters with rich vegetation, although some are specialised extremophiles. Species richness and conservation value of most groups in the fly ash lagoons did not significantly differ from the post-mining ponds, except for species richness of benthos, zooplankton, and macrophytes, which were slightly lower in the fly ash lagoons. Although the concentrations of some heavy metals (mainly Se, V, and As) were significantly higher in the fly ash lagoons, they did not significantly affect species richness or conservation value of the local communities. The differences in species composition therefore does not seem to be caused by water chemistry. Altogether, we have shown that fly ash lagoons are refuges for threatened aquatic species, and we thus suggest maintaining water bodies during site restoration after the cessation of fly ash deposition. Based on our analyses of environmental variables, we discuss suitable restoration practices that efficiently combine biodiversity protection and environmental risk reduction.
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•Fly ash sedimentation lagoons host endangered freshwater biodiversity.•Higher concentration of some heavy metals does not affect the conservation potential.•Endangered species of oligotrophic fishless waters and rare extremophiles were found.•Habitat descriptors important for the endangered species were detected.•Fly ash restoration should combine biodiversity conservation and risks suppression.
It has been argued recently that the initial dispersal of anatomically modern humans from Africa to southern Asia occurred before the volcanic “supereruption” of the Mount Toba volcano (Sumatra) at ...∼74,000 y before present (B.P.)—possibly as early as 120,000 y B.P. We show here that this “pre-Toba” dispersal model is in serious conflict with both the most recent genetic evidence from both Africa and Asia and the archaeological evidence from South Asian sites. We present an alternative model based on a combination of genetic analyses and recent archaeological evidence from South Asia and Africa. These data support a coastally oriented dispersal of modern humans from eastern Africa to southern Asia ∼60–50 thousand years ago (ka). This was associated with distinctively African microlithic and “backed-segment” technologies analogous to the African “Howiesons Poort” and related technologies, together with a range of distinctively “modern” cultural and symbolic features (highly shaped bone tools, personal ornaments, abstract artistic motifs, microblade technology, etc.), similar to those that accompanied the replacement of “archaic” Neanderthal by anatomically modern human populations in other regions of western Eurasia at a broadly similar date.
This volume comprises the authoritative work from the International Committee for the Conservation of the Industrial Heritage - the international group dedicated to industrial archaeology and ...heritage - detailing the latest approaches to the conservation of the global industrial heritage. With contributions from over thirty specialists in archaeology and industrial heritage, Industrial Heritage Re-tooled establishes the first set of comprehensive best practices for the management, conservation, and interpretation of historical industrial sites. This book:-defines the meaning and scope of industrial heritage within an international context;-addresses the identification and conservation of the material remains of industry;-covers subjects as diverse as documentation and recording of industrial heritage, industrial tourism, and the teaching of industrial heritage in museums, schools, and universities.
Worldwide, microplastics (MPs) have been commonly recognized as a threat to soil ecosystems. Terrestrial soils are widely contaminated by MPs due to the application of sewage sludge and wastewater, ...plastic mulching, littering, the input of tire wear from roads and atmospheric deposition. Within the last decade, an increasing number of individual studies focused on item counts and masses of MPs in different global soil environments. We reviewed these studies to achieve a representative picture of common degrees of contamination. The majority of the prospected agricultural and horticultural sites were exposed to sewage sludge and mulching film application and showed concentrations of <13 000 items kg−1 dry soil and 4.5 mg kg−1 dry soil. Microplastic concentrations in soils in the vicinity of municipal areas were thereby 10 times larger compared to rural sites. The measurement of masses was generally underrepresented compared to item numbers, and mass data were often generated from microscopic analyses by using shape-to-mass models instead of direct measurements. Extreme values, such as on industrial sites, exceed the common concentrations by 2 to 4 orders of magnitude, which might be attributed not only to the land use but also to the applied methods of measurement. Campaigns that focus on other entry pathways like composts, road dust runoff and littering or land uses like grassland, forest, fallow and wilderness as well as industrial sites and landfills were underrepresented or nonexistent. Background loads, such as atmospheric deposition, were often not excluded from the measurements and, thus, the studies might overestimate the contribution of the analyzed entry pathway to the total load. Other studies focused on light density MP, e.g., from mulching films, and therefore underestimated the amount of soil MP. Despite these limitations, the data give an impression of the spectrum of global MP concentrations and are a good basis for experiments examining the effects of MPs on exposed soils. Based on the collected data, we identified problems of past studies and recommend that future experimentation take into account standardized methods of extraction and quantification, a proper characterization of the sampling sites and their history as well as the exploration of as yet underrepresented entry pathways and land uses.
Air pollution‐induced tanning of human skin Grether‐Beck, S.; Felsner, I.; Brenden, H. ...
British journal of dermatology (1951),
November 2021, Letnik:
185, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Summary
Background
Melanism is more frequent in animals living in polluted areas on urban–industrial sites. Given that an increasing number of people are exposed to elevated air pollution levels, it ...is possible that environmental pollutants affect melanogenesis in human skin. Epidemiological studies have shown that exposure to traffic‐related air pollutants such as diesel exhaust particles (DEP) is associated with more clinical signs of hyperpigmentation. However, mechanistic evidence linking DEP exposure to pigmentation has been elusive.
Objectives
To develop an ex␣vivo skin model to allow for repetitive topical application of relevant ambient DEP, and to provide proof of concept in humans.
Methods
We measured skin pigmentation, melanin and pigmentation‐associated gene expression, and evaluated oxidative stress.
Results
Repetitive exposure of ex␣vivo skin to DEP at nontoxic concentrations increased skin pigmentation. This increase was visible to the naked eye, time dependent, and associated with an increase in melanin content and the transcription of genes involved in de novo melanin synthesis. Similarly, in healthy participants (n = 76), repetitive topical application of DEP at nontoxic concentrations increased skin pigmentation. DEP‐induced pigmentation was mediated by an oxidative stress response. After the application of DEP, epidermal antioxidants were depleted, lipid peroxidation and oxidative DNA damage were enhanced, and in a vehicle‐controlled, double‐blind clinical study DEP‐induced pigmentation was prevented by the topical application of an antioxidant mixture.
Conclusions
Similar to solar radiation, air pollutants cause skin tanning. As eumelanin is an antioxidant, it is proposed that this response serves to protect human skin against air pollution‐induced oxidative stress.
What is already known about this topic?
It has been reported that animals living in polluted environments have darker skin because they produce more melanin as a result.
What does this study add?
Exposure to traffic‐related air pollution causes increased pigmentation of human skin.
The tanning response was seen in cultured human skin models and also in␣vivo upon exposure to nontoxic concentrations of air pollutants.
What is the translational message?
The results provide a mechanistic explanation to previous epidemiological studies linking chronic exposure to traffic‐related air pollution with skin hyperpigmentation.
Plain language summary available online
Calcium peroxide (CaO2) has been proven to oxidize various organic pollutants when they exist as a single class of compounds. However, there is a lack of research on the potential of unactivated CaO2 ...to treat mixed chlorinated organic pollutants in soils. This study examined the potential of CaO2 in treating soils co-contaminated with p-dichlorobenzene (p-DCB) and p-chloromethane cresol (PCMC). The effects of CaO2 dosage and treatment duration on the rate of degradation were investigated. Furthermore, the collateral effects of the treatment on treated soil characteristics were studied. The result showed that unactivated CaO2 could oxidize mixed chlorinated organic compounds in wet soils. More than 69% of the pollutants in the wet soil were mineralized following 21 days of treatment with 3% (w/w) CaO2. The hydroxyl radicals played a significant role in the degradation process among the other decomposition products of hydrogen peroxide. Following the oxidation process, the treated soil pH was increased due to the formation of calcium hydroxide. Soil organic matter, cation exchange capacity, soil organic carbon, total nitrogen, and certain soil enzyme activities of the treated soil were decreased. However, the collateral effects of the system on electrical conductivity, available phosphorus, and particle size distribution of the treated soil were not significant. Likewise, since no significant release of heavy metals was seen in the treated soil matrix, the likelihood of metal ions as co-pollutants after treatment was low. Therefore, CaO2 can be a better alternative for treating industrial sites co-contaminated with chlorinated organic compounds.
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•CaO2, 3% (w/w), degraded 69.26% of the pollutants in 21 days.•CaO2 oxidized components of the mixed pollutant at different rates.•OH was responsible species for the degradation of the pollutants.•Destruction of SOM is a significant challenge for the utilization of solid CaO2.•The likelihood of metal ions as co-contaminants after treatment is lower.
When coal dust accumulations are exposed to air for a period of time, they are gradually oxidised by oxygen. This eventually leads to ignition, causing fires and explosions and exerting a pernicious ...environmental impact. In the present study, the ignition risk of coal spontaneous combustion (CSC) under the influence of NaCl, KCl, and MgCl2 solution was analysed using hot plate tests. Methods for determining the suppression efficiency of each of the chloride salts were designed according to the minimum ignition temperature of the dust layer and ignition delay time. An evaluation methodology with consideration of both temperature and time parameters was formulated. The results showed that the maximum inhibitory effect and the minimum risk index were observed when MgCl2 solution was used. Moreover, the mechanisms by which the salts suppressed CSC was investigated and compared according to their physicochemical effects. Notably, NaCl and KCl promoted CSC in the smouldering process, whereas the hydrate formed by MgCl2 solution (MgCl2·6H2O) consistently inhibited CSC. The methodology proposed in present study provides significance access to evaluate the ignition risk of CSC in industrial sites where coal dust accumulates.
•NaCl, KCl, and MgCl2 were used as inhibitors to study the ignition risk of CSC.•The hot plate test was used to simulate the typical industrial scenarios.•By establishing the risk indicator matrix, the ignition risk index was calculated.•Of the three chloride salts, MgCl2 had the best inhibitory effects on CSC.
Open interior sands represent a highly threatened habitat in Europe. In recent times, their associated organisms have often found secondary refuges outside their natural habitats, mainly in sand ...pits. We investigated the effects of different restoration approaches, i.e. spontaneous succession without additional disturbances, spontaneous succession with additional disturbances caused by recreational activities, and forestry reclamation, on the diversity and conservation values of spiders, beetles, flies, bees and wasps, orthopterans and vascular plants in a large sand pit in the Czech Republic, Central Europe. Out of 406 species recorded in total, 112 were classified as open sand specialists and 71 as threatened. The sites restored through spontaneous succession with additional disturbances hosted the largest proportion of open sand specialists and threatened species. The forestry reclamations, in contrast, hosted few such species. The sites with spontaneous succession without disturbances represent a transition between these two approaches. While restoration through spontaneous succession favours biodiversity in contrast to forestry reclamation, additional disturbances are necessary to maintain early successional habitats essential for threatened species and open sand specialists. Therefore, recreational activities seem to be an economically efficient restoration tool that will also benefit biodiversity in sand pits.
Because agglomeration economies may create competitive advantage and each location has a unique array of agglomeration economies, where should firms locate? We combine fundamental economic and ...strategy concepts to: (1) determine when firms must locate proximately to access factor pools; (2) show that factor pools controlled by fewer firms are less useful to new entrants; and (3) demonstrate that certain firms risk aiding competitors when contributing to efficient factor pools. We find support for our predictions with a test on new U.S. manufacturing entrants from 1985 to 1994, using an empirical specification that separates agglomeration levels from agglomeration economies.
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