Light Pollution Research Articles

Characterization and Source Analysis of Heavy Metal(loid)s Pollution in Soil of an Industrial Park in Kunming, China

This study investigated the characteristics and sources of heavy metal(loid) pollution in the soil of a key industrial park in Kunming, China. In total, 60 soil samples (40 from agricultural land and 20 from construction land) were collected from and around the park. The soil pH and contents of Arsenic (As), lead (Pb), copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg), nickel (Ni), and chromium (Cr) were measured. The contents of the eight heavy metal(loid)s were analyzed using the background values of heavy metal(loid)s in the Kunming soil. The pollution load, geoaccumulation, and Nemero Comprehensive Pollution Indices were used for environmental risk evaluation. Cluster and principal component analyses were used to resolve heavy metal(loid) sources. Cd was enriched in construction and agricultural soils. As, Hg, Cd, Pb, Cu, and Zn exhibited large spatial differentiation and were significantly affected by the external environment. A regional pollution load index of 3.02 indicated overall heavy pollution. The pollution load index for each heavy metal(loid) indicated light pollution. The geoaccumulation index indicated relatively severe As, Cd, Cu, Pb, and Zn pollution. The Nemero Composite Pollution Index value showed that the study area was heavily polluted, with construction land being mildly polluted by Cd, and agricultural land being moderately polluted. The results of the spatial distribution show that there were high levels of contamination in the center. Correlation and principal component analyses showed that the pollution sources of the eight heavy metal(loid)s varied. Hg, Cd, and Pb originate primarily from industrial and agricultural pollution. Traffic sources significantly impacted Cu, Pb, Cd, and Cr. Natural sources are the main sources of Cr, Ni, and Cd. Ni is also affected by industrial sources, whereas Zn and Cu are affected by agricultural pollution. The influences of As, Cd, and Pb on the surface soil in the study area were more serious. Cd is more widely polluted and should be a priority in controlling soil heavy metal(loid)s.

Effectiveness of the recirculation air cleaner in real conditions at variation of the air flow and PM2.5 content

Technical data on the effectiveness of air purifiers are usually obtained in laboratory conditions in special aerosol stands with test chambers or boxes of a small volume, while in real conditions the purifiers are used in rooms with a volume of at least 40-60 m3 with a permanent presence of people (distribution respiratory diseases emitted with breathing) and entry of PM2.5..PM10 particles into the room from working equipment (printers, chargers, power tools, etc.). There are already enough scientific materials on this matter, which prove that the actual efficiency of air purifiers in real conditions is much lower than the data given by the manufacturers. Therefore, there is a need to determine the optimal performance of the air purifier in real conditions in order to achieve the WHO recommended levels of safe indoor pollution with a maximum time interval of 1 hour, besides, taking into account that the air outside has a higher level of pollution with particles of PM 2.5. In this study, we strive to obtain a PM 2.5 value of 5 μg/m3 with a PM2.5 level in the air outside of 16.7 μg/m3. The calculated value of CADR for light pollution should be at least half of the power of the air purifier for the projected cleaning duration of no more than 1 hour. A smaller value of CADR leads to further accumulation of pollutants, which reduces the work of the cleaner. In this study, the value of CADR was at L=100 m3/hour the value of CADR= 59 m3/hour with the efficiency of filter inserts in 73% and natural sedimentation of particles in 25%, and at L=310 m3/hour the value of CADR= 59 m3/hour at efficiency of filter inserts in 94% and natural sedimentation of particles in 18%. The process of natural deposition and the amount of external pollution do not allow to clean the air without the use of mechanical filtration for any of the pollutants specified in the study.

The influence of exploration activities of a potential lithium mine to the environment in Western Serbia

The proposed exploitation of the Jadar Valley lithium/borate deposit in Serbia, by the Rio Tinto Corporation, indicates that it would become large-scale processing of boron- and lithium-containing ore. It would be one of the world’s very first lithium mines in populated and agricultural area. The company claims that the envisioned mining will be in accordance with environmental protection requirements. The Jadar Valley deposits have been claimed to cover 90% of Europe’s current lithium needs. Yet, local opposition to the mining has arisen due to potential devastating impacts on groundwater, soil, water usage, biodiversity loss, and waste accumulation. Research drilling by the mining company has already produced environmental damage, with mine water containing high levels of boron leaking from exploratory wells and causing crops to dry out. Furthermore, our investigations reveal substantially elevated downstream concentrations of boron, arsenic, and lithium in nearby rivers as compared to upstream regions. Additionally, here we show that soil samples exhibit repeated breaches of remediation limit values with environmental consequences on both surface and underground waters. With the opening of the mine, problems will be multiplied by the tailings pond, mine wastewater, noise, air pollution, and light pollution, endangering the lives of numerous local communities and destroying their freshwater sources, agricultural land, livestock, and assets.

Analysis of The Effect of Floating Net Cages on Reservoir Water Quality

The use of Darma Waduk is as a source of clean water and a place of fish cultivation in the form of net cages. The number of floating net cages that currently exist is 6521, and the number continues to increase quite significantly from the previous year. The existence of floating net cages affects water quality, while water quality is an aspect to be considered in water utilization. The study aims to analyze the impact of floating net cages on water quality and efforts to control the floating net cage population in Darma Waduk. The research uses a quantitative and qualitative approach, starting with surveys and interviews with floating net cage farmers and related services. Subsequently, water samples were taken, and the results of laboratory tests were analyzed using the Pollution Index (IP) method. The results of the calculation using the pollution index (IP) method at the first point (PDAM Intake Area) obtained a result of 4.14, at the second point (around the floating net cage area of the village of Cipasung) a value of 3.76, and at the third point (in the floating net cage village of Jagara) a score of 4.12. The results of the research showed that the water quality taken from the three points of the sample included light pollution when referring to the class I water quality standard according to PP No. 22 for 2021. However, the presence of household and agricultural waste also contributes to the pollution burden in the Darma Valley.

Measuring light pollution with smart photometers

Measuring light pollution with smart photometers

The power of spectrally enhanced artificial night-time lights data: Assessing NTL risks along the urban-natural interface

Artificial night-time lights (NTL) have long been known for their adverse effects on humans and the environment. Recent studies report that the severity of NTL impact on organisms is associated not only with its intensity but also a spectrum. The spectral resolution of freely available satellite NTL data is restricted to red, green, and blue sub-spectra, which are significantly wider than the ranges of vulnerability, reported by laboratory studies for various species. The present study is the first attempt to overlap spectrum-specific NTL data, describing the intensities of light emitted by different lamp types with relatively narrow emission peaks, with the sites where species vulnerable to specific NTL sub-spectra were detected. We overlap those light intensity maps with increasingly detailed maps of natural areas located along the urban-natural interface of the Haifa region. We analyze light pollution in the ecological corridors, which host numerous species with different, but unknown, spectrum-specific effects of NTL (a coarse-level analysis), and in the sites of several species, with either known or unknown spectrum-specific effects of NTL (a fine-level analysis). We show that a considerable part of the ecological corridors is polluted by metal halide and high-pressure sodium lamps which may negatively influence plants, bees, sea turtles, birds, and mammals. One habitat site of the Near Eastern fire salamander (Salamandra infraimmaculata) is polluted by lamps with green-light emission peaks which may explain the low reproductive success of this population. Despite the study limitations, related to the region-specific NTL data of spectrum-specific resolution and scarcity of evidence about the spectrum-specific NTL harmful effects on organisms, we believe that the obtained results would contribute to the elaboration of more informed fine-tuned artificial lighting policies which would diminish the burden of urban built-up zones on their neighboring natural areas.

Extra-pair paternity in two passerine birds breeding in a gradient of urbanisation.

Urbanisation has been increasing worldwide in recent decades, driving environmental change and exerting novel selective pressures on wildlife. Phenotypic differences between urban and rural individuals have been widely documented in several taxa. However, the extent to which urbanisation impacts mating strategies is less known. Here, we investigated extra-pair paternity variation in great tits (Parus major) and blue tits (Cyanistes caeruleus) breeding in nestboxes set in a gradient of urbanisation in Warsaw, Poland, over three breeding seasons. Urbanisation was quantified as the amount of light pollution, noise pollution, impervious surface area (ISA) and tree cover within a 100-m radius around each nestbox. We obtained genotypes for 1213 great tits at 7344 SNP markers and for 1299 blue tits at 9366 SNP markers with a genotyping-by-sequencing method, and inferred extra-pair paternity by computing a genomewide relatedness matrix. We report higher extra-pair paternity in blue tits breeding in more urbanised areas, for example, with higher light pollution and ISA, and lower tree cover. However, no such trend was found in great tits. Late-stage survival of individual nestlings in both species was not associated with paternity or urbanisation proxies, thus we were not able to detect fitness benefits or drawbacks of being an extra-pair offspring in relation to urbanisation. Our results contribute to the growing body of knowledge reporting on the effects of urbanisation on avian ecology and behaviour, and confirm species-specific and population-specific patterns of extra-pair paternity variation.

Over 30 years of monitoring and implementing the Bern Convention's recommendations for the protection of Mediterranean sea turtles

The Bern Convention was the first international treaty dedicated to the conservation of European wildlife and habitats. Their task is to review member states’ efforts depending on their commitments for flora and fauna protection. Since 1993, the Mediterranean Association to Save the Sea Turtles (MEDASSET) has been advocating for the creation and enforcement of legislation at the national, European Union, and regional levels. MEDASSET monitors the implementation of the Convention’s recommendations in two major sea turtle nesting areas in Greece (Laganas and Kyparissia Bays) and four in Turkey (Anamur, Kazanli, Fethiye, and Patara). In Greece, the most important pressures are uncontrolled tourist boat activity, illegal construction, and beach furniture management issues reported in Laganas Bay, and light pollution, illegal construction, and unhindered vehicle access in Kyparissia. In Turkey, Anamur is negatively impacted by the lack of law enforcement, illegal sand extraction, and coastal development, and Kazanli has been subjected to the release of toxic waste from a Soda Chrome Factory since 2000. Moreover, Fethiye and Patara are affected by the lack of management and protection, and the rapid construction and touristic development. Nevertheless, some positive steps have been made due to MEDASSET and other NGO activities over the past 30 years, such as the establishment of the National Marine Park of Zakynthos, and the issuing of the Bern Convention’s recommendations for each one of the aforementioned nesting sites.

The Ecological Economics of Light Pollution: Impacts on Ecosystem Service Value

Light pollution has detrimental impacts on wildlife, human health, and ecosystem functions and services. This paper explores the impact of light pollution on the value of ecosystem services. We use the Simplified All-Sky Light Pollution Ratio (sALR) as a proxy for the negative impact of light pollution and the Copernicus PROBA-V Global Landcover Database as our proxy of ecosystem service value based on previously published ecosystem service values associated with a variety of landcovers. We use the sALR value to ‘degrade’ the value of ecosystem services. This results in a 40% reduction in ecosystem service value in those areas of the world with maximum levels of light pollution. Using this methodology, the estimate of the annual loss of ecosystem service value due to light pollution is USD 3.4 trillion. This represents roughly 3% of the total global value of ecosystem services and 3% of the global GDP, estimated at roughly USD 100 trillion in 2022. A summary of how these losses are distributed amongst the world’s countries and landcovers is also presented.

Relative importance of intensity and spectrum of artificial light at night in disrupting behavior of a nocturnal rodent.

The influence of light spectral properties on circadian rhythms is of substantial interest to laboratory-based investigation of the circadian system and to field-based understanding of the effects of artificial light at night. The trade-offs between intensity and spectrum regarding masking behaviors are largely unknown, even for well-studied organisms. We used a custom LED illumination system to document the response of wild-type house mice (Mus musculus) to 1-h nocturnal exposure of all combinations of four intensity levels (0.01, 0.5, 5 and 50 lx) and three correlated color temperatures (CCT; 1750, 1950 and 3000 K). Higher intensities of light (50 lx) suppressed cage activity substantially, and consistently more for the higher CCT light (91% for 3000 K, 53% for 1750 K). At the lowest intensity (0.01 lx), mean activity was increased, with the greatest increases for the lowest CCT (12.3% increase at 1750 K, 3% increase at 3000 K). Multiple linear regression confirmed the influence of both CCT and intensity on changes in activity, with the scaled effect size of intensity 3.6 times greater than that of CCT. Activity suppression was significantly lower for male than for female mice. Assessment of light-evoked cFos expression in the suprachiasmatic nucleus at 50 lx showed no significant difference between high and low CCT exposure. The significant differences by spectral composition illustrate a need to account for light spectrum in circadian studies of behavior, and confirm that spectral controls can mitigate some, but certainly not all, of the effects of light pollution on species in the wild.

Enhancing Environmental Sustainability: Risk Assessment and Management Strategies for Urban Light Pollution

Light pollution imposes significant and far-reaching adverse effects on human society, necessitating its stringent regulation. However, intervention policies could be customized to suit the unique characteristics of each region, taking into account local conditions. To address this challenge, we have developed a comprehensive light pollution risk assessment model using a combination of objective and subjective weighting methods, including analytic hierarchy process (AHP), independent weighting method (IWM), entropy weight method (EWM), coefficient of variation (CV), criteria importance through intercriteria correlation (CRITIC), and principal component analysis (PCA). This model facilitates a systematic evaluation of light pollution risk levels across diverse regions in China. Subsequently, we have proposed intervention policies targeting light pollution risk reduction and assessed their efficacy using the synthetic control method. Our findings reveal elevated light pollution risk levels in coastal and mountainous regions with heightened concentrations closer to urban centers. Strategies focused on enhancing lighting hardware, optimizing lighting schedules, and upgrading light sources demonstrated the impact on reducing light pollution risk levels (LPRL). This study not only lays a solid theoretical foundation for assessing urban light pollution risks but furnishes empirical evidence to aid relevant authorities in formulating effective light pollution control strategies.

Reflection–Polarization Characteristics of Greenhouses Studied by Drone-Polarimetry Focusing on Polarized Light Pollution of Glass Surfaces

Drone-based imaging polarimetry is a valuable new tool for the remote sensing of the polarization characteristics of the Earth’s surface. After briefly reviewing two earlier drone-polarimetric studies, we present here the results of our drone-polarimetric campaigns, in which we measured the reflection–polarization patterns of greenhouses. From the measured patterns of the degree and angle of linear polarization of reflected light, we calculated the measure (plp) of polarized light pollution of glass surfaces. The knowledge of polarized light pollution is important for aquatic insect ecology, since polarotactic aquatic insects are the endangered victims of artificial horizontally polarized light sources. We found that the so-called Palm House of a botanical garden has only a low polarized light pollution, 3.6% ≤ plp ≤ 13.7%, while the greenhouses with tilted roofs are strongly polarized-light-polluting, with 24.8% ≤ plp ≤ 40.4%. Similarly, other tilted-roofed greenhouses contain very high polarized light pollution, plp ≤ 76.7%. Under overcast skies, the polarization patterns and plp values of greenhouses practically only depend on the direction of view relative to the glass surfaces, as the rotationally invariant diffuse cloud light is the only light source. However, under cloudless skies, the polarization patterns of glass surfaces significantly depend on the azimuth direction of view and its angle relative to the solar meridian because, in this case, sunlight is the dominant light source, rather than the sky. In the case of a given direction of view, those glass surfaces are the strongest polarized-light-polluting, from which sunlight and/or skylight is reflected at or near Brewster’s angle in a nearly vertical plane, i.e., with directions of polarization close to horizontal. Therefore, the plp value is usually greatest when the sun shines directly or from behind. The plp value of greenhouses is always the smallest in the green spectral range due to the green plants under the glass.

Intelligent Acoustic and Optical Anomaly Monitoring System for Expressway Tunnels Based on the Internet of Things

A smart sound and light anomaly monitoring system for highway tunnels based on Internet of Things technology was studied to address the issues of highway tunnel lighting systems. By utilizing Internet of Things technology, the tunnel lighting system is combined with abnormal sound recognition. Through the design of algorithm models, the recognition of abnormal sound inside the tunnel and the intelligent control of the lighting system is achieved. By pruning and validating the hidden layer nodes of the model, a more streamlined abnormal sound recognition model is obtained. Through experimental verification, this model has the highest recognition accuracy among all models, with a recognition rate of 91.75% at a compression rate of 20%. Compared with Average Percentage of Zeros (APoZ), Random Pruning and Mean Activation, the recognition rate is increased by 2.64%, 1.47% and 1.40%, respectively. In the design of tunnel lighting, fuzzy control is applied to the lighting inside the tunnel to improve the driving safety of drivers and further reduce the power consumption of excessive lighting in the tunnel. Through experiments, it has been proven that the system can work well, saving up to 727[Formula: see text] of energy per day.

Light Pollution in India: An Emerging Environmental Concern

Light Pollution in India: An Emerging Environmental Concern

Human dermal exposure to short- and medium-chain chlorinated paraffins: Effect of populations, activities, gender, and haze pollution

Human dermal exposure to chlorinated paraffins (CPs) has not been well documented. Therefore, hand wipes were collected from four occupational populations to analyze short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) in order to estimate dermal uptake and oral ingestion via hand-to-mouth contact. The total CP levels (∑SCCPs and ∑MCCPs) in wipes ranged from 71.4 to 2310 µg/m2 in security guards, 37.6 to 333 µg/m2 in taxi drivers, 20.8 to 559 µg/m2 in office workers, and 20.9 to 932 µg/m2 in undergraduates, respectively. Security guards exhibited the highest levels of ∑SCCPs among four populations (p < 0.01). In undergraduates engaged in outdoor activities, C13 emerged as the most dominant SCCPs homologue group, followed by C12, C11, and C10. The levels of ∑SCCPs and ∑MCCPs in males in light haze pollution were significantly higher than that in heavy haze pollution (p < 0.05). The median estimated dermal absorption dose of SCCPs and MCCPs via hand was 22.2 and 104 ng (kg of bw)−1 day−1, respectively, approximately 1.5 times the oral ingestion [12.3 and 74.4 ng (kg of bw)−1 day−1], suggesting that hand contact is a significant exposure source to humans.

Urban Biodiversity Index for Trees: A Climate Adaptation Measure for Cities Based on Tree Inventories

A historically large percentage of the world’s population has moved to urban areas in the past few decades, causing various negative effects for the environment, such as air, noise, water, and light pollution; land degradation; and biodiversity loss. Under the current climate crisis, cities are anticipated to play an essential part in adaptation strategies to extreme atmospheric events. This study aims at developing indicators at an urban scale that can highlight adaptation progress by investigating relevant data (especially in situ) and statistics at a pan-European level in support of the EU’s strategy for adapting to the impacts of climate change. The proposed indicator, Urban Biodiversity Indicator for Trees (UBI4T), which can be derived from city tree inventories, assesses one essential component of urban biodiversity by computing the proportion of native, alien, invasive, and toxic tree species spatially across a city. According to our findings (applying the UBI4T for Amsterdam and exploring its policy potential for Barcelona), the UBI4T can offer crucial information for decision and policy makers, as well as stakeholders of a city, with the aim of conducting dedicated and effective strategic initiatives to restore, improve, and protect nature in the urban environment, thus contributing to adaptation and resilience to extreme atmospheric events in cities.

Author Correction: Monitoring, trends and impacts of light pollution

Author Correction: Monitoring, trends and impacts of light pollution

Multi‐method sampling increases detectability and assessment of spatio‐temporal interactions of mammals and birds in wetland habitats

Abstract Freshwater habitats support high levels of biodiversity and provide important habitat for wetland‐dependent taxa; however, impairment of aquatic connectivity through wetland loss, stream alterations and light pollution impacts species persistence and community resilience. Quantifying occupancy of these habitats to assess their use by mammals and birds can be challenging, especially for cryptic species. This study examines wetland habitat use by mammals and birds, and their spatial and temporal relationships within the Beaver Hills Biosphere in Alberta, Canada. As part of a multi‐method detection approach, camera boxes, cameras on beaver dams, and camera rafts allowed for multivariate analyses to determine temporal and spatial patterns of habitat use and species associations, while field sampling and environmental DNA (eDNA) provided data on site occupancy by a subset of semi‐aquatic mammals. From ~50,000 images, over 84 species were detected, including 52 species of birds and 25 species of mammals. Several species were spatially associated, and although most species of mammals exhibited temporal overlap, there were distinct differences, especially on beaver dams where predators such as coyotes and white‐tailed deer shared the same space. Temporally, birds were detected most often during the day and mammals at night. During new moon phases, use of beaver dams by beavers decreased dramatically, and use of camera rafts by muskrats increased. Winter field surveys allowed for a broad overview of wetland occupancy and abundance of some species, particularly by beavers and muskrats, and occasionally winter use by other semi‐aquatic mammals. Where there was limited detection of more cryptic species of semi‐aquatic mammals, eDNA analysis successfully detected American water shrew, American mink, North American river otter and northern bog lemming more often than camera and field methods. Applying a multi‐method monitoring approach for mammals and birds in wetland habitats is critical at a time when freshwater systems are experiencing dramatic declines in relative abundance of monitored wildlife populations, with many of these species underrepresented in conventional surveys.

Atmospheric H2O2 during haze episodes in a Chinese megacity: Concentration, source, and implication on sulfate production

Atmospheric hydrogen peroxide (H2O2), as an important oxidant, plays a key role in atmospheric chemistry. To reveal its characteristics in polluted areas, comprehensive observations were conducted in Zhengzhou, China from February 22 to March 4, 2019, including heavy pollution days (HP) and light pollution days (LP). High NO concentrations (18 ± 26 ppbv) were recorded in HP, preventing the recombination reaction of two HO2• radicals. Surprisingly, higher concentrations of H2O2 were observed in HP (1.5 ± 0.6 ppbv) than those in LP (1.2 ± 0.6 ppbv). In addition to low wind speed and relative humidity, the elevated H2O2 in HP could be mainly attributed to intensified particle-phase photoreactions and biomass burning. In terms of sulfate formation, transition-metal ions (TMI)-catalyzed oxidation emerged as the predominant oxidant pathway in both HP and LP. Note that the average H2O2 oxidation rate increased from 3.6 × 10−2 in LP to 1.1 × 10−1 μg m−3 h−1 in HP. Moreover, the oxidation by H2O2 might exceed that of TMI catalysis under specific conditions, emerging as the primary driver of sulfate formation.

Light pollution from led lighting systems and ways of reducing its environmental consequences

Light pollution from led lighting systems and ways of reducing its environmental consequences