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Climatic oscillations are considered primary factors influencing the distribution of various life forms on Earth. Large species adapted to cold climates are particularly vulnerable to extinction due to climate changes. In our study, we investigated whether temperature increase since the Late Pleistocene and the contraction of environmental niche during the Holocene were the main factors contributing to the decreasing range of moose (Alces alces) in Europe. We also examined whether there were significant differences in environmental conditions between areas inhabited by moose in Europe and Asia, that could support the division of moose into western and eastern forms, as suggested by genetic and morphological data. We analysed environmental conditions in the locations of 655 subfossil and modern moose occurrences over the past 50,000 years in Eurasia. We found that the most limiting climatic factor for the moose distribution since the Late Pleistocene was July temperature. More than 90 % of moose records were found in areas where mean summer temperature was below 19 °C, with July temperatures showing over 3 times narrower interquartile range compared to January temperatures. We identified significant differences in environmental conditions between areas inhabited by the European and Asiatic moose. In Europe, the species occurred in regions with milder climates, higher primary productivity, and more frequently within forest biomes compared to Asiatic individuals. The moose range shifted more in the west-east than in the south-north direction during the Holocene climate warming in Europe. We conclude that although the area of suitable moose habitat has increased since 12-8 ka years BP, as demonstrated by environmental niche modeling, the retreat of A. alces in large areas of Europe was likely caused by anthropogenic landscape change (e.g., deforestation) and overhunting by humans during the late Holocene rather than by climate warming during the Pleistocene to Holocene transition., Competing Interests: Declaration of competing interest Due to the Ukrainian laws established since the Russian invasion in February 2022, Ukrainian scientists employed in the Ukrainian institutions are not allowed to be included as co-authors in the same papers with Russian researchers. That is why the name of professor Bogdan Ridush from the Yuriy Fedkovych Chernivtsi National University in Ukraine, who participated in this study, based on his request, has been excluded from the list of authors and moved to the Acknowledgements., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Abstract Tropical and subtropical forest ecosystems play an important role in the global carbon regulation. Despite increasing evidence for effects of biodiversity (species diversity, functional diversity and functional dominance), stand structural attributes, stand age and environmental conditions (climate and topography) on tree carbon storage, the relative importance of these drivers at large scale is poorly understood. It is also still unclear whether biodiversity effects on tree carbon storage work through niche complementarity (i.e. increased tree carbon storage due to interspecific resource partitioning) or through the mass-ratio effect (tree carbon storage regulated by dominant traits within communities). Here we analyze tree carbon storage and its drivers using data of 480 plots sampled across subtropical forests in China. We use multiple regression models to test the relative effects of biodiversity, stand structural attributes, stand age and environmental conditions on tree carbon storage, and use a partial least squares path model to test how these variables directly and/or indirectly affect tree carbon storage. Our results show that tree carbon storage is most strongly affected by stand age, followed by climate, biodiversity and stand structural attributes. Stand age and climate had both direct and indirect (through species diversity, functional dominance and stand structural attributes) effects. We find that tree carbon storage correlates with both species diversity and functional dominance after stand age and environmental drivers are accounted for. Our results suggest that niche complementarity and the mass-ratio effect, not necessarily mutually exclusive, both play a role in maintaining ecosystem functioning. Our results further indicate that biodiversity conservation might be an effective way for enhancing tree carbon storage in natural, species-rich forest ecosystems. Graphical abstract Unlabelled Image Highlights • Biodiversity enhances tree carbon storage in subtropical forests. • Niche complementarity and mass-ratio effect both play a role in maintaining ecosystem functioning. • Stand age, stand structure and environmental conditions all affect tree carbon storage. [ABSTRACT FROM AUTHOR]

Severe air pollution associated with the rapid urbanization is a pressing issue in China. Moreover, the public awareness of environmental protection in China is awakening, which poses enormous pressure on governments to enforce environmental regulations. The study of environmental problems from the public perspective plays a crucial role in effective environmental governance. The Baidu search engine is the China's largest search engine. The search index of haze based on Baidu search engine reflects the public concern on air quality in China. The aim of this study is to uncover important relationships between public concern and air quality monitoring data based on the case study of haze pollution crisis in China. The results indicate that: (1) the year 2013 is the turning point of the public concern on air quality in China; (2) according to daily data analysis, the search index of haze has increased progressively with increased PM 2.5 concentration with a time lag of 0–4 days and the lag time has a declining tendency from 2013 to 2017; (3) according to annual data analysis, the public concern showed a weak correlation with air quality and they showed an opposite temporal trend. However, when the long-term annual trend was removed, the strong positive correlation emerges between the fluctuation parts of the search index of haze and monitoring data of air quality. This indicates the public is more sensitive to the short-term fluctuation of air quality. The results of this paper provide statistical evidence on the evolution of public concern on air quality from 2013 to 2017. This study will help policy makers to better understand the patterns of the public's perception of environmental problems and consequently improve the government's capability to deal with these challenges. [ABSTRACT FROM AUTHOR]

Non-methane hydrocarbons (NMHCs) play an important role in the atmospheric environment. However, NMHC emissions from agricultural fields, especially their variations with straw return, are poorly understood. Therefore, a field study comprising two treatments, i.e., (1) S0 (straw removal) and (2) S1 (incorporation of maize straw at a rate of 9000 kg ha −1 ), was conducted in a straw-returned maize cropping system to characterize NMHC emissions as well as to estimate the effect of straw return on those emissions. Using a Gas Chromatography-Mass Spectrometer (GC–MS) method, 28 types of NMHCs were identified. The total NMHC emission from S0 was 2018 g ha −1 , where 1-methyl-3-propyl-benzene, (1-methylethyl)-benzene, and toluene were obviously predominant, whereas the total NMHC emission from S1 was 1903 g ha −1 , where 1-methyl-3-propyl-benzene, 2-methyl-pentane, and (1-methylethyl)-benzene were the main species. The results showed that straw return had opposing effects on NMHC emissions, ranging from −55.4% to 478.6%. Overall, the total NMHC emission with returned straw alone decreased by 2963 ng kg straw −1  h −1 . Furthermore, NMHC fluxes had higher correlations with soil temperature than with soil moisture or pH. Notably, the higher correlations of NMHC fluxes with 10 cm soil temperature than with 5 cm soil temperature indicate that soil in the deeper layer might play a more important role in NMHC fluxes. The results also suggest that more field study is needed to accurately estimate the effect of straw return on NMHC emissions from agroecosystems and fully understand its underlying mechanism. [ABSTRACT FROM AUTHOR]

This paper reports the first study which comprises the seasonal, diurnal variability, source characterization, ozone forming potential and risk assessment of volatile organic compounds (VOCs) at three sites (two urban and one rural) in the National Capital Territory of Delhi, India. The study was performed during three seasons of the year 2013–14 and two different categories of VOCs (aromatics and halogenated) have been selected. The study used the sampling and analytical procedures of NIOSH methods. Results showed that the mean concentration of sum of VOCs (∑VOC) is significantly higher at urban sites (110.0 and 137.4 μg/m 3 for JN and CP, respectively) as compared to the rural site, DP (56.5 μg/m 3 ). The contribution of individual to total VOC concentrations is noticed to be very similar at all the three sites. Most of the VOCs are observed to be significantly higher in winter followed by summer and autumn. Diurnal cycles of aromatic VOCs are highly influenced by the vehicular traffic and photochemical oxidations which showed higher and lower levels during morning/evening and daytime, respectively. Diagnostic ratios of the toluene/benzene (ranged from 0.65 to 13.9) infers the vehicular traffic might be the main contributing source in the urban sites while xylene/benzene ratio (ranged from 0.7 to 2.8) confirms the VOCs are transported to rural site from the nearby urban areas. Correlation and factor analysis suggested the sources are group of different species (traffic emissions, solvent usage and industrial) rather than single gas. The analysis of reactivity in terms of Prop-Equiv concentrations and ozone forming potential indicated that m/p-xylene and toluene are the main VOC contributing to the total ozone formation in urban and rural sites, respectively. Hazard ratios and lifetime cancer risk values exceeded the permissible standards established by USEPA and WHO suggests that the people are at significant risk. [ABSTRACT FROM AUTHOR]

Cutleaf coneflower ( Rudbeckia laciniata L. var. digitata ) is native to Great Smoky Mountains National Park (GRSM) and an ozone bioindicator species. Variety ampla , whose ozone sensitivity is less well known, is native to Rocky Mountain National Park (ROMO). In the early 2000s, researchers found putative ozone symptoms on var. ampla and rhizomes were sent to Appalachian State University to verify that the symptoms were the result of ozone exposure. In 2011, potted plants were exposed to ambient ozone from May to August. These same plants were grown in open-top chambers (OTCs) in 2012 and 2013, and exposed to charcoal-filtered (CF), non-filtered (NF), elevated ozone (EO), NF + 50 ppb in 2012 for 47 days and NF + 30/NF + 50 ppb ozone in 2013 for 36 and 36 days, respectively. Ozone symptoms similar to those found in ROMO (blue-black adaxial stippling) were reproduced both in ambient air and in the OTCs. Both varieties exhibited foliar injury in the OTCs in an exposure-dependent manner, verifying that symptoms resulted from ozone exposure. In two of the three study years, var. digitata appeared more sensitive than var. ampla . Exposure to EO caused reductions in ambient photosynthetic rate ( A ) and stomatal conductance ( g s ) for both varieties. Light response curves indicated that ozone reduced A , g s , and the apparent quantum yield while it increased the light compensation point. In CF air, var. ampla had higher light saturated A (18.2 ± 1.04 vs 11.6 ± 0.37 μmol m − 2 s − 1 ), higher light saturation (1833 ± 166.7 vs 1108 ± 141.7 μmol m − 2 s − 1 ), and lower Ci/Ca ratio (0.67 ± 0.01 vs 0.77 ± 0.01) than var. digitata . Coneflowers in both Parks are adversely affected by exposure to ambient ozone and if ozone concentrations increase in the Rocky Mountains, greater amounts of injury on var. ampla can be expected. [ABSTRACT FROM AUTHOR]

In the scope of the first WDF management cycle, a multi-municipality sanitation system with secondary treatment was implemented in 2005 in Ria de Aveiro coastal lagoon, with the treated effluent discharging into the Atlantic Ocean through a submarine outfall. The lagoon water chemical status was evaluated regarding dissolved inorganic nutrients and chlorophyll a before and after 2005. The S. Jacinto outfall has effectively reduced the point source nutrient loads (ammonium and phosphate) into Ria de Aveiro, representing a step forward for the implementation of the WFD, through eutrophication abatement. However, the lagoon remains exposed to non-point nitrogen sources, as a consequence of the current land use and water management, which in a scenario of winter extreme precipitation events, nutrients increase through surface run-off. Besides, in a combined scenario of low freshwater input into the lagoon and favourable oceanic condition, nutrients enter through Ria outer boundary coming from the S. Jacinto outfall. Thus, changes in the system hydrodynamics in the context of global change might pose new challenges regarding the WFD second management cycle involving the second river basin management plan and the first flood risk management plan, foreseeing the ‘Good’ ecological status in all Ria's Water Bodies. [ABSTRACT FROM AUTHOR]

Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the variation of surface O 3 concentration recorded at seven selected stations in Malaysian Borneo. Hourly surface O 3 data covering the period 2002 to 2013, obtained from the Malaysian Department of Environment (DOE), were analysed using statistical methods. The results show that the concentrations of O 3 recorded in Malaysian Borneo during the study period were below the maximum Malaysian Air Quality Standard of 100 ppbv. The hourly average and maximum O 3 concentrations of 31 and 92 ppbv reported at Bintulu (S3) respectively were the highest among the O 3 concentrations recorded at the sampling stations. Further investigation on O 3 precursors show that sampling sites located near to local petrochemical industrial activities, such as Bintulu (S3) and Miri (S4), have higher NO 2 /NO ratios (between 3.21 and 5.67) compared to other stations. The normalised O 3 values recorded at all stations were higher during the weekend compared to weekdays (unlike its precursors) which suggests the influence of O 3 titration by NO during weekdays. The results also show that there are distinct seasonal variations in O 3 across Borneo. High surface O 3 concentrations were usually observed between August and September at all stations with the exception of station S7 on the east coast. Majority of the stations (except S1 and S6) have recorded increasing averaged maximum concentrations of surface O 3 over the analysed years. Increasing trends of NO 2 and decreasing trends of NO influence the yearly averaged maximum of O 3 especially at S3. This study also shows that variations of meteorological factors such as wind speed and direction, humidity and temperature influence the concentration of surface O 3 . [ABSTRACT FROM AUTHOR]

Public concerns over airborne trace elements (TEs) in metropolitan areas are increasing, but long-term and multi-site observations of size-resolved aerosol TEs in China are still lacking. Here, we identify highly elevated levels of atmospheric TEs in megacities and industrial sites in a Beijing–Tianjin–Hebei urban agglomeration relative to background areas, with the annual mean values of As, Pb, Ni, Cd and Mn exceeding the acceptable limits of the World Health Organization. Despite the spatial variability in concentrations, the size distribution pattern of each trace element was quite similar across the region. Crustal elements of Al and Fe were mainly found in coarse particles (2.1–9 μm), whereas the main fraction of toxic metals, such as Cu, Zn, As, Se, Cd and Pb, was found in submicron particles (< 1.1 μm). These toxic metals were enriched by over 100-fold relative to the Earth's crust. The size distributions of Na, Mg, K, Ca, V, Cr, Mn, Ni, Mo and Ba were bimodal, with two peaks at 0.43–0.65 μm and 4.7–5.8 μm. The combination of the size distribution information, principal component analysis and air mass back trajectory model offered a robust technique for distinguishing the main sources for airborne TEs, e.g., soil dust, fossil fuel combustion and industrial emissions, at different sites. In addition, higher elemental concentrations coincided with westerly flow, indicating that polluted soil and fugitive dust were major sources of TEs on the regional scale. However, the contribution of coal burning, iron industry/oil combustion and non–ferrous smelters to atmospheric metal pollution in Northern China should be given more attention. Considering that the concentrations of heavy metals associated with fine particles in the target region were significantly higher than those in other Asian sites, the implementations of strict environmental standards in China are required to reduce the amounts of these hazardous pollutants released into the atmosphere. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this 12-year study was to assess the nekton (fish, decapod crustaceans) response to freshwater inputs (rainfall, dam discharges) in a temperate estuary with regulated riverine inflow. Although interannual variability in river discharges to the Guadalquivir estuary has been extremely high since the construction of a dam in 1930, a significant decreasing trend in the dam''s discharges has been observed in the last 80years. During this study, an alternation of wet, standard and dry years occurred in the estuarine area but no significant long-term trend was observed. River discharge, in turn, showed a considerable interannual variability and a significantly decreasing long-term trend. Freshwater inputs had an immediate effect on estuarine salinity and turbidity, and consequently on prey availability (mysids). Although 124 nektonic species were collected, only 47 of them (adding up to 99.7% of total abundance) were regularly present in the estuary: 32 marine migrants, 13 estuarine species and 2 diadromous species. Well-defined temporal changes in species composition and abundance yielded clear seasonal patterns in the estuarine nektonic community. Considerable intermonth and interannual changes were occasionally observed relating to freshwater inputs, mainly in winter/autumn of wet years. Thus, within each two-month period, some significant interannual differences in the nektonic community were also observed, with marine migrants tending to be more abundant in dry years. However, changes in the studied nektonic community did not show long-term trends. In conclusion, natural and human-controlled freshwater inputs currently play a significant role in determining the physicochemical conditions and the biota of the Guadalquivir estuary. However, although freshwater input seemed to transitorily affect the estuarine nekton, either directly (flushing out) or indirectly (through changes in salinity, turbidity and prey availability), a quick reestablishment of the estuarine nekton (strong resilience) was observed following freshwater inputs together with the recovery of environmental conditions within the estuary. [Copyright &y& Elsevier]

The public, increasingly well-informed about the problem of excessive noise, is taking actions for the development of new transport infrastructure projects and improvement of existing infrastructure. In addition, many countries have implemented mandatory Environmental Impact Assessment procedures. As a result, the construction of sound barriers has become a common measure, which can be used by an agency to mitigate potentially significant noise impacts. A sound barrier, eventually, will become part of the surrounding landscape and could be a cause of impact for ecosystems, the road users and those who live alongside the road. Basically, this article discusses these potential effects in the context of environmental assessment procedures. In addition, results of a pilot survey conducted at a residential area affected by the construction of a barrier are presented. Although most residents felt that sleeping conditions improved after the barrier was built, most important negative reactions are the loss of sunlight and visual impact. [Copyright &y& Elsevier]

Abstract: Contamination of foodstuff with mycotoxins such as ochratoxins is a major matter of concern for human and animal health. In Aspergillus species, ochratoxin synthesis depends on several environmental factors. The aims of this work were to evaluate the effect of water activity (0.995–0.85), temperature (15, 25 and 30 °C), incubation time (7, 14 and 21 days) and their interactions on OTA production on peanut, maize kernels, dried grapes and coffee beans meal extract agar medium by eight strains of Aspergillus section Nigri isolated from human food in Argentina. The optimum temperature for OTA production was 25 or 30 °C depending on the strains assayed, in most cases the highest OTA levels were achieved after 7 days of incubation, whereas this situation occurred at 15 °C after 14 days of incubation for only one strain. The maximum OTA level was obtained at earlier growth states when incubation temperature increased. In general, OTA concentration increased as water activity (a W) increased with no significant production at 0.85–0.91 a W under all temperature levels tested. Production occurred over a range of temperatures (15–30 °C) with optimum production at 30 °C depending on a W assayed. The knowledge of Aspergillus section Nigri ecophysiology is critical in the development and prediction of the risk models of raw material and final product contamination by these species under fluctuating and interacting environmental parameters. [Copyright &y& Elsevier]

Different filter materials and electrical charge elimination methods were used to investigate the weighing accuracy of filter papers under different environmental conditions. The results show that the standard deviations (S.D.) of weight data for glass fiber and MCE filters were substantial without environmental control, whether or not the electrical charge eliminators were used. Values of 0.157 and 0.349 mg were determined for glass and MCE filters, respectively. The accuracy of weighing was substantially improved and the S.D. was reduced to 0.01 and 0.09 mg for glass fiber and MCE filters, respectively, after applying the environmental control conditions. For PVC and Teflon filters, the accuracy of weighing was good, even in the uncontrolled environmental conditions, whether or not the electrical charge eliminators were used. The S.D. values of weighing data of PVC and Teflon filters were 0.007 and 0.011 mg, respectively. [Copyright &y& Elsevier]

Most birds incubate their eggs, which requires time and energy at the expense of other activities. Birds generally have two incubation strategies: biparental where both mates cooperate in incubating eggs, and uniparental where a single parent incubates. In harsh and unpredictable environments, incubation is challenging due to high energetic demands and variable resource availability. We studied the relationships between the incubation behaviour of sandpipers (genus Calidris) and two environmental variables: temperature and a proxy of primary productivity (i.e. NDVI). We investigated how these relationships vary between incubation strategies and across species among strategies. We also studied how the relationship between current temperature and incubation behaviour varies with previous day's temperature. We monitored the incubation behaviour of nine sandpiper species using thermologgers at 15 arctic sites between 2016 and 2019. We also used thermologgers to record the ground surface temperature at conspecific nest sites and extracted NDVI values from a remote sensing product. We found no relationship between either environmental variables and biparental incubation behaviour. Conversely, as ground-surface temperature increased, uniparental species decreased total duration of recesses (TDR) and mean duration of recesses (MDR), but increased number of recesses (NR). Moreover, small species showed stronger relationships with ground-surface temperature than large species. When all uniparental species were combined, an increase in NDVI was correlated with higher mean duration, total duration and number of recesses, but relationships varied widely across species. Finally, some uniparental species showed a lag effect with a higher nest attentiveness after a warm day while more recesses occurred after a cold day than was predicted based on current temperatures. We demonstrate the complex interplay between shorebird incubation strategies, incubation behaviour, and environmental conditions. Understanding how species respond to changes in their environment during incubation helps predict their future reproductive success. Unlabelled Image • We used ground-surface temperature and a primary productivity index to describe environmental conditions. • Most biparental species showed no relationship between incubation behaviour and environmental conditions. • Uniparental species showed a higher attentiveness, shorter and more frequent recesses in warm than in cold conditions. • Relationships found between uniparental species' incubation behaviour and temperature vary with primary productivity. • We found lag effects of past temperature, supporting the hypothesis that some species use their reserves during cold days. [ABSTRACT FROM AUTHOR]

In urban watersheds, street tree leaf litter is a critical biogenic source of phosphorus (P) in stormwater runoff. Stormwater extracts P from leaf litter and transports it, through the storm sewer network, to a receiving waterbody potentially causing downstream eutrophication. The goal of this study is to understand P leaching dynamics of two prevalent tree species (Norway maple (Acer platanoides) and green ash (Fraxinus pennsylvanica)) in three urban residential watersheds in Madison, Wisconsin, USA. Leaf litter was collected from the three basins during Fall 2017 and 2018. Laboratory experiments showed an initial rapid total dissolved phosphorus (TDP) release that gradually plateaued over a 48-hour period. The total TDP released from Norway maple (2.10 mg g−1) was greater than from green ash (1.60 mg g−1). Within the same species, increased fragmentation of leaves led to more rapid initial TDP release, but not greater total TDP release. Increased aging of senescent leaves decreased total TDP release. Incubation temperature and volume of water in contact with leaves may not be critical factors affecting TDP leaching dynamics. Predictive equations were derived to characterize time-variable TDP release of both Norway maple and green ash leaves. Potential TDP release from leaf litter estimated using these equations was compared with field-measured end-of-pipe TDP loads in one of the study watersheds. Our results indicate that preventing leaf litter from accumulating in streets is an important stormwater quality control measure. Unlabelled Image • Tree leaf litter is a source of phosphorus (P) in urban stormwater runoff. • Leaf litter P release varies with species, degree of fragmentation and age. • Norway Maple leaf litter released more dissolved P than Green Ash. • Equations were developed to predict time-variable P release from leaf litter. [ABSTRACT FROM AUTHOR]

The use of stormwater ponds along the highways is shown to be an effective alternative to conventional systems, which are usually sewers. These ponds have the potential to combine their primary function of pollution and peak flow control with the promotion of biodiversity. The present study focuses on comparing natural and highway stormwater ponds in terms of environmental conditions and biodiversity of macroinvertebrate communities. Twelve highway stormwater ponds and nineteen natural ponds (located within or in the vicinity of cultivated landscape) were explored for the number of taxa, community composition, and selected environmental variables: pH, conductivity, pond surface area, the number of ponds within 1 km radius, and the distance to nearest neighboring pond. Highway stormwater ponds showed much higher conductivity, which is a good proxy for chloride concentration and highway pollutants. In addition, the surface area of stormwater ponds was almost twice as big as that of natural ponds. The biological community composition was very different between the two types of ponds, and the number of taxa was slightly higher in the highway stormwater ponds. The most important variables responsible for the variation in the biological community composition were conductivity, pond surface area, and the number of ponds within 1 km radius. This study supports that, in addition to their role in pollution and peak flow control, stormwater ponds have the potential to provide a habitat that may otherwise be unavailable along the highway. Unlabelled Image • Diversity and community composition differed between natural and highway ponds. • Conductivity and pond surface area were associated to the observed differences. • Highway ponds provide habitats that are otherwise unavailable along roads. [ABSTRACT FROM AUTHOR]