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The impact of public transportation on carbon emissions: a panel quantile analysis based on Chinese provincial data Texto completo
2019
Jiang, Yong | Zhou, Zhongbao | Liu, Cenjie
Although the Chinese government emphasizes the significance of public transportation development and encourages green travel, no empirical study has examined whether the expansion of public transportation facilitates the mitigation of carbon emissions. To this end, we employ a panel quantile regression to test the endogenous relationship between public transportation scale and carbon emissions. The results suggest that the effect of public transportation scale on carbon emissions is heterogeneous across China’s provinces based on the level of carbon emissions. Even so, the results still support a stable inverted U-shaped relationship between public transportation scale and carbon emissions for provinces with different levels of carbon emissions. That is, when public transportation scale exceeds a threshold value, the relationship between public transportation and carbon emissions will turn from positive to negative. Our findings provide evidence advocating for public transportation development and green travel. It is of great significance for China to respond to climate changes.
Mostrar más [+] Menos [-]Elucidation of contamination sources for poly- and perfluoroalkyl substances (PFASs) on Svalbard (Norwegian Arctic) Texto completo
2019
Skaar, Jøran Solnes | Ræder, Erik Magnus | Lyche, Jan Ludvig | Ahrens, Lutz | Kallenborn, Roland
A combination of local (i.e. firefighting training facilities) and remote sources (i.e. long-range transport) is assumed to be responsible for the occurrence of per- and polyfluoroalkyl substances (PFASs) in Svalbard (Norwegian Arctic). However, no systematic elucidation of local PFASs sources has been conducted yet. Therefore, a survey was performed aiming at identifying local PFAS pollution sources on the island of Spitsbergen (Svalbard, Norway). Soil, freshwater (lake, draining rivers), seawater, meltwater run-off, surface snow and coastal sediment samples were collected from Longyearbyen (Norwegian mining town), Ny-Ålesund (research facility) and the Lake Linnévatnet area (background site) during several campaigns (2014–2016) and analysed for 14 individual target PFASs. For background site (Linnévatnet area, sampling during April to June 2015), ΣPFAS levels ranged from 0.4 to 4 ng/L in surface lake water (n = 20). PFAS in meltwater from the contributing glaciers showed similar concentrations (~ 4 ng/L, n = 2). The short-chain perfluorobutanoate (PFBA) was predominant in lake water (60–80% of the ΣPFASs), meltwater (20–30%) and run-off water (40%). Long-range transport is assumed to be the major PFAS source. In Longyearbyen, five water samples (i.e. 2 seawater, 3 run-off) were collected near the local firefighting training site (FFTS) in November 2014 and June 2015, respectively. The highest PFAS levels were found in FFTS meltwater run-off (118 ng/L). Perfluorooctane sulfonic acid (PFOS) was the most abundant compound in the FFTS meltwater run-off (53–58% PFASs). At the research station Ny-Ålesund, seawater (n = 6), soil (n = 9) and freshwater (n = 10) were collected in June 2016. Low ΣPFAS concentrations were determined for seawater (5–6 ng/L), whereas high ΣPFAS concentrations were found in run-off water (113–119 ng/L) and soil (211–800 ng/g dry weight (dw)) collected close to the local FFTS. In addition, high ΣPFAS levels (127 ng/L) were also found in freshwater from lake Solvatnet close to former sewage treatment facility. Overall, at both FFTS-affected sites (soil, water), PFOS was the most abundant compound (60–69% of ΣPFASs). FFTS and landfill locations were identified as major PFAS sources for Svalbard settlements.
Mostrar más [+] Menos [-]PCB congener data of gas-phase, dissolved water, air-water fluxes in southern Lake Michigan, 2010 Texto completo
2019
Boesen, Aaron C | Martinez, Andres | Hornbuckle, Keri C
Airborne and dissolved water PCB congener specific concentrations from southern Lake Michigan 2010. The data were used to estimated instantaneous air-water PCB fluxes.
Mostrar más [+] Menos [-]Agricultural water pollution: key knowledge gaps and research needs Texto completo
2019
Evans, A. | Mateo-Sagasta, Javier | Qadir, M. | Boelee, Eline | Ippolito, A.
Number of microplastic particles on periwinkle pedal mucus in experimental setups Texto completo
2019
Gutow, Lars | Bartl, Kevin | Saborowski, Reinhard | Beermann, Jan
The rapid dissemination of microplastics in many habitats of the oceans has raised concerns about the consequences for marine biota and ecosystems. Many adverse effects of microplastics on marine invertebrates are consequences of ingestion. Accordingly, the identification of mechanisms that facilitate the uptake of microplastics is essential for the evaluation of possible implications for marine organisms and food webs. Gastropods produce mucus for locomotion. Gastropod pedal mucus naturally retains formerly suspended micro-organisms, such as bacteria, microalgae, and seaweed spores. The retained organisms are consumed by gastropods that forage on pedal mucus. Here, we investigated the potential of gastropod pedal mucus to retain suspended microplastic particles and make them available for ingestion by periwinkles that forage on the contaminated mucus. In laboratory experiments, mucus of the periwinkles Littorina littorea and Littorina obtusata efficiently retained microplastics. Retention of microplastics varied between mucus from conspecifics of different size but not between mucus from either species. The density of microplastics in mucus trails increased concomitantly with the experimental particle concentration but was independent of incubation time. Aging of mucus and, particularly, desiccation affected the retention of microplastics. Periwinkles ingested microplastics when foraging on the contaminated mucus. Our results reveal a functional link between biogenic accumulation of microplastics and their trophic transfer by marine benthic herbivores into marine food webs.
Mostrar más [+] Menos [-]Two decades of monitoring in marine debris ingestion in loggerhead sea turtle, Caretta caretta, from the western Mediterranean. Texto completo
2019
Doménech, F. | Aznar Avendaño, Francisco Javier | Raga Esteve, Juan Antonio | Tomás Aguirre, Jesús
Anthropogenic marine debris is one of the major worldwide threats to marine ecosystems. The EU Marine Strategy Framework Directive (MSFD) has established a protocol for data collection on marine debris from the gut contents of the loggerhead sea turtle (Caretta caretta), and for determining assessment values of plastics for Good Environmental Status (GES). GES values are calculated as percent turtles having more than average plastic weight per turtle. In the present study, we quantify marine debris ingestion in 155 loggerhead sea turtles collected in the period 1995e2016 in waters of western Mediterranean (North-east Spain). The study aims (1) to update and standardize debris ingestion data available from this area, (2) to analyse this issue over two decades using Zero-altered (hurdle) models and (3) to provide new data to compare the only GES value available (off Italian waters). The composition of marine debris (occurrence and amounts of different categories) was similar to that found in other studies for the western Mediterranean and their amounts seem not to be an important threat to turtle survival in the region. Model results suggest that, in the study area, (a) period of stranding or capture, (b) turtle size and (c) latitude are significant predictors of anthropogenic debris ingestion (occurrence and amount) in turtles. The GES value for late juvenile turtles (CCL>40 cm) has decreased in the last ten years in the study area, and this is very similar to that obtained in Italian waters. We also provide a GES value for early juvenile turtles (CCL 40 cm) for the first time. Recommendations arising from this study include ensuring use of (1) the standardized protocol proposed by the MSFD for assessing marine debris ingestion by loggerhead sea turtles and (2) the ecology of the turtles (neritic vs oceanic), rather than their size, to obtain GES values.
Mostrar más [+] Menos [-]Quantifying air pollution vulnerability and its distributional consequences: Some perspectives from Delhi Texto completo
2019
Gupta, Shivani | Das, Sukanya | Murty, M. N.
This paper estimates Vulnerability Index of air pollution in Delhi taking into account exposure, susceptibility and coping capacity of households. A general health production function model and a vulnerability assessment framework are used for this purpose. Data was collected through a survey of sample households located in close vicinity to 10 air pollution monitoring stations in Delhi. The estimated vulnerability index is used to show the effect of household exposure to air pollution. The vulnerability index takes into consideration sample households' socio-economic status, demographic profile and other characteristics. Result showed that households of lower socio-economic status were the most vulnerable to air pollution and its consequences.
Mostrar más [+] Menos [-]The effects of exposure to air pollution on subjective well-being in China Texto completo
2019
Zhang, Xin | Chen, Xi | Zhang, Xiaobo
This paper studies the impact of six main air pollutants on three key dimensions of subjective well-being (SWB) – life satisfaction, hedonic happiness and mental health. We match a nationally representative survey in China with local air quality and rich weather conditions according to the exact date and county of each interview. By making use of variations in exposures to air pollution across similar respondents living in the same county, we find that PM2.5 reduces hedonic happiness and increases the rate of depressive symptoms, but does not affect life satisfaction. Our results show that the benefits of reducing air pollution would be higher if the hidden costs of air pollution on SWB in China are taken into account.
Mostrar más [+] Menos [-]Seawater carbonate chemistry and shell microstructure, mechanical properties of an edible estuarine oyster Texto completo
2019
Meng, Yuan | Guo, Zhenbin | Yao, Haimin | Yeung, Kelvin W K | Thiyagarajan, Vengatesen
Ocean acidification (OA) is well-known for impairing marine calcification; however, the end response of several essential species to this perturbation remains unknown. Decreased pH and saturation levels (Omega) of minerals under OA is projected to alter shell crystallography and thus to reduce shell mechanical properties. This study examined this hypothesis using a commercially important estuarine oyster Magallana hongkongensis. Although shell damage occurred on the outmost prismatic layer and the undying myostracum at decreased pH 7.6 and 7.3, the major foliated layer was relatively unharmed. Oysters maintained their shell hardness and stiffness through altered crystal unit orientation under pH 7.6 conditions. However, under the undersaturated conditions (Omega Cal ~ 0.8) at pH 7.3, the realigned crystal units in foliated layer ultimately resulted in less stiff shells which indicated although estuarine oysters are mechanically resistant to unfavorable calcification conditions, extremely low pH condition is still a threat to this essential species.
Mostrar más [+] Menos [-]Soil pollution | Soil pollution (Nova Science Publishers)
2019
"Oil pollution receives less attention when compared to air pollution and water pollution. However, soil pollution is grabbing more attention nowadays. Undoubtedly, soil is an indispensable environmental matrix for the growth of any terrestrial plants. Nevertheless, the rapid growth rate of population expansion and urbanization exceeds the sustainability and recovery capability of the ecosystem. This has virtually resulted in soil pollution. The sources of soil pollution can come from various point and non-point sources. Of the obvious and commonest ones are domestic wastes, untreated or insufficient treatment of industrial discharges, husbandry wastes and agricultural uses of fertilizers, pesticides and herbicides. The purpose of this book is to provide the latest, if not the complete, updated information regarding the soil pollution from three main perspectives, namely, sources, health effects and management strategies in the agricultural and urban areas. The intended readers of this book include academicians, policy-makers, university students, teachers and researchers. This book contains eleven chapters. All chapters in this book consist of sources of pollutants (heavy metal monitoring) (Chapters One, Three, Six, Seven, Eight, Ten and Eleven), the application of the monitoring data for the human health risk assessment (Chapters One, Four, Five and Nine), and lastly, management strategies for the polluted soils (Chapters Two, Ten and Eleven). This book presents a thorough compilation of existing information on soil heavy metal pollution in the form of critical review papers (Chapters One, Two, Ten and Eleven) as well as original research papers (Chapters Three, Four, Five, Six, Seven, Eight and Nine)"--
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