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Resultados 3811-3820 de 8,010
How air pollution lowers the domestic value-added ratio in exports: an empirical study of China Texto completo
2021
Yu, Lan | Ying, Ruiyao | Zhang, Bingbing
This paper analyzes the theoretical mechanism and transmission channel for the impact of air pollution on firms’ domestic value-added ratio (DVAR) in exports. Based on the matched Chinese Industrial Enterprises Database and China Customs Enterprise Database, the DVAR in exports is measured, and this mechanism is empirically tested with standard measurement methods. The study concludes that air pollution is not conducive to raising the DVAR during the sample period. This conclusion remains robust to many issues, such as endogeneity, measurement error, extension of the sample interval, substitution of the air pollution index, and policy changes. The impact of air pollution on the DVAR varies by the type of firm ownership, size, and age, as well as the size and location of the city. In addition, the negative impact of air pollution on the DVAR grows with increases in the PM2.5 concentration. The growing factor prices of domestic intermediate goods and the falling productivity due to air pollution are important transmission channels for the negative impact of air pollution on the DVAR. In order for firms to open up on all fronts through quality trade development, we recommend the prevention and control of air pollution, fueling internal driving forces for firms’ independent innovation, and encouraging firms to target the medium- and high-end markets.
Mostrar más [+] Menos [-]Does foreign direct investments impair the ecological footprint? New evidence from the panel quantile regression Texto completo
2021
Chowdhury, Mohammad Ashraful Ferdous | Shanto, Peal Ahamed | Ahmed, Afsana | Rumana, Rabeya Hossain
This study examines the impact of foreign direct investments on ecological footprint along with other explanatory variables of 92 countries from the year 2001 to 2016. Here, we applied the panel quantile regression model to meet the purpose of our study as it considers unobserved country heterogeneity, unlike other statistical methods. The study reveals that foreign direct investment has a positive relationship with the ecological footprint in each quantile except one, which proves the constancy of the pollution haven hypothesis. Moreover, we also tried to detect the impact of economic growth, manufacturing value-added, the percentage of world exports, and institutional quality on the ecological footprint in this study. The findings of this study also reveal that economic growth and manufacturing value-added are negatively associated with the ecological footprint. With respect to the percentage of world exports and institutional quality, we found a positive relationship with the ecological footprint. From the result of our study, different policy implications have been proposed for host countries and foreign investors on improving the economy through foreign direct investment with minimal ecological footprint.
Mostrar más [+] Menos [-]Determination of toxic elements in meat products from Serbia packaged in tinplate cans Texto completo
2021
Stojanović, Branislav | Janković, Saša | Đorđević, Vesna | Marjanovic, Sonja | Vasilev, Dragan | Stojanović, Zdenka | Balaban, Milica | Antić, Vesna
This work aimed to examine the influence of the storage period on the content of toxic elements (As, Cd, Hg, and Pb) in five types of canned meat products regularly used in the Serbian Armed Forces. Cans of beef goulash (BG), pork ragout (PR), spam (SP), liver pate (LP), and meatballs in tomato sauce (MB), produced according to military standards and stored under regular conditions, were analyzed. Meat products were packed in tin cans made according to special requirements in terms of tin and varnish application and stored for up to 6 years. The content of toxic elements varied depending on the analyzed product. The highest average content of arsenic was in BG (10.00 μg/kg), cadmium in LP (35.91 μg/kg), and mercury and lead in PR (15.04 and 8.00 μg/kg, respectively). The average concentrations of As, Cd, Hg, and Pb in all types of canned meat products were significantly lower than the maximum permitted levels in food currently in force by local and EU legislation. The storage period did not significantly affect the level of toxic elements, although higher concentrations were found in samples stored for more than 2 years. Examination of raw materials, spices, and additives showed that the highest Cd and Pb concentrations, which can affect the total level of these elements in meat products, were found in red ground pepper (Cd above 150 μg/kg) and dish supplement (Pb of 250 μg/kg). The assessment of the weekly intake of toxic elements through canned meat showed that it is significantly lower than the values that affect adversely to human health, as determined by the FAO/WHO and EFSA. However, as there is a constant possibility of contamination of raw materials and food additives, primarily due to environmental pollution, it is recommended to monitor the content of heavy metals in food permanently and assess their risk to human health.
Mostrar más [+] Menos [-]Nitrogen and metal pollution in the southern Caspian Sea: a multiple approach to bioassessment Texto completo
2021
Costantini, Maria Letizia | Agah, Homira | Fiorentino, Federico | Irandoost, Farnaz | Trujillo, Francisco James Leon | Careddu, Giulio | Calizza, Edoardo | Rossi, Loreto
The Caspian Sea hosts areas of high ecological value as well as industrial, leisure, and agricultural activities that dump into the water body different kinds of pollutants. In this complex context, a proper description of the origin and potential sources of pollution is necessary to address management and mitigation actions aimed at preserving the quality of the water resource and the integrity of the ecosystems. Here, we aimed at detecting sources of both nitrogen inputs, by N stable isotope analysis of macroalgae, and metals in macroalgae and sediments in two highly anthropized coastal stretches at the Iranian side of the Caspian Sea. Sampling was done near the mouth of rivers and canals draining agricultural and urbanized areas. In the westernmost waters, facing a port city, low macroalgal δ¹⁵N signatures indicated industrial fertilizers as the principal source of pollution. By contrast, in the central coastal waters, facing touristic areas, the high macroalgal δ¹⁵N indicated N inputs from wastewaters. Here the lowest dissolved oxygen concentrations in waters were associated with excess dissolved inorganic nitrogen. Metal concentrations varied largely in the study areas and were lower in macroalgae than in sediments. Localized peaks of Pb and Zn in sediments were observed in the central coastal sites as probable byproducts of mining activity transported downstream. By contrast, Cr and Ni concentrations were high in all sampling sites, thus potentially representing hazardous elements for marine biota. Overall, macroalgal δ¹⁵N coupled with metal analysis in macroalgae and sediments was useful for identifying the main sources of pollution in these highly anthropized coastal areas. This double approach in comprehensive monitoring programs could thus effectively inform stakeholders on major environmental threats, allowing targeted management measures.
Mostrar más [+] Menos [-]Snow as a contributor to spring flooding in Belarus Texto completo
2021
Meshyk, Aleh | Barushka, Maryna | Marozava, Viktoryia
There are some peculiarities in instrumental observation over snow cover characteristics in Belarus and those of neighboring countries. Maximum snow water equivalent varies around Belarus from 107 mm in Brest to 207 mm in Novogrudok. It differs significantly in terms of years, which is proved by high values of variation coefficients (Cᵥ). Maximums are observed in the south and south-west of Belarus. Minimum values are typical for central and north-eastern parts of Belarus with a stable snow cover. There is a distinct correlation between snow water equivalent and the stations’ altitude. We observe a space-time variability of SWE in Belarus’ river catchments. Changes in SWE are of cyclic nature. They correlate with current climate fluctuations. In certain parts of Belarus, there is a trend in reduction of SWE up to 8–10 mm in 10 years. This research determines the amount of water that forms spring flood runoff in the catchments of Belarus’ big rivers. Possible daily snow melting is calculated in the research as well. It reaches 26 mm in its maximum and 5–6 mm on average. The amount of river runoff water, which is formed within Belarus, is 58 km³. The amount of melt water is 11 km³, which accounts for 19%. In particularly extreme years, melt water reaches 29 km³, which is over a half of all annual river runoff.
Mostrar más [+] Menos [-]Risk assessment and investigation of landfill leachate as a source of emerging organic contaminants to the surrounding environment: a case study of the largest landfill in Jinan City, China Texto completo
2021
Wang, Kun | Reguyal, Febelyn | Zhuang, Tao
Emerging organic contaminants (EOCs) have been widely studied in landfill leachates but not in the surrounding environment of landfills. In this study, two sampling campaigns were conducted to determine 45 EOCs in landfill leachates and environmental samples near a landfill in East China. Our study focused on the seasonal occurrence and spatial distribution of the target EOCs, as well as their ecological risks. The results showed 13 out of 45 EOCs were detectable and achieved individual concentrations that ranged from 2.0 to 5080 ng/L in the landfill leachates. Most of the detected EOCs exhibited higher concentrations in the leachates collected in summer than in winter. Effective removal of the EOCs by a two-stage disc tube reverse osmosis (DTRO) system led to a significant reduction in their concentration levels (< LOQ ~ 49 ng/L) in treated leachates. Eight EOCs (< LOQ ~ 62.7 ng/L) were detected in the groundwater adjacent to the landfill and had a similar composition pattern to raw leachates. The contamination levels of the target EOCs in groundwater decreased with the distance of sampling sites from the landfill. In soil samples, the occurrence of target EOCs was not consistent with raw or treated landfill leachates. Spatially, no apparent difference in the EOC concentrations was observed in the soil nearby the landfill. Crop plants sorbed the EOCs contained in soil (< LOQ ~ 30.4 ng/L), but they were not able to bioconcentrate the contaminants in either roots or edible parts. Risk assessment suggested that the individual EOC likely posed medium to high risks to aquatic organisms in groundwater while negligible impacts to human health through consumption of vegetables. To the best of our knowledge, this is the first report on the contribution of landfill leachates to EOC contamination in both aquatic and soil environments in East China. Our findings emphasized the importance of investigating EOCs in landfill leachates and accumulative environmental risks of EOCs in the neighboring environment of landfills in China.
Mostrar más [+] Menos [-]Impact of precipitation disparity on groundwater fluctuation in a semi-arid region (Vellore district) of southern India using geospatial techniques Texto completo
2021
Venkatesan, G. | Subramani, T. | Karunanidhi, D. | Sathya, U. | Li, Peiyue
In the present study, impact of precipitation disparity on groundwater level fluctuation was carried out in Vellore district, Tamil Nadu, India, using geospatial techniques. There are five rain gauge stations in the study area in which three rain gauge stations, namely Alangayam, Jolarpettai and Pernampet, receive more precipitation when compared with the average annual precipitation of Tamil Nadu state (920 mm). The other two stations, namely Madanur and Natrampalli, receive less than 920 mm of precipitation annually. The overall average annual precipitation of the study area is 913.6 mm. More than 100 mm precipitation is received in all the five rain gauge stations during southwest (SW) and northeast (NE) monsoon seasons. The maximum monthly precipitation is usually recorded during the month of November and the minimum precipitation is recorded during June. The post-monsoon precipitation is around 10.8 mm, which is almost negligible in the study area. The contribution of precipitation by various seasons is in the following sequence: Southwest monsoon > Northeast monsoon > Pre-monsoon > Post-monsoon. The spatial disparity study indicates that the intensity of average annual, pre-monsoon and post-monsoon precipitations increase towards west in the study area. The intensity of precipitation is more in the northern part during SW monsoon season, whereas the intensity is more in the southern part during NE monsoon season. The spatial disparity analysis of groundwater fluctuation shows that the depth of groundwater (below ground level) increases towards west during all the monsoon seasons. The minimum, mean and maximum depths of occurrence of groundwater in this region are, respectively, 1.6, 9.6 and 21.15 m. Declining trend in the regional groundwater level is observed from December to June because of less precipitation during non-monsoon season. However, the monsoon (both SW and NE monsoon) precipitation recharges the groundwater from June to December to reach the maximum in the month of December.
Mostrar más [+] Menos [-]Spatiotemporal changes on land surface temperature, land and water resources of host communities due to artisanal mining Texto completo
2021
Owolabi, Ayodele Olumuyiwa | Amujo, Kolade | Olorunfemi, Idowu Ezekiel
Assessment of land use/land cover change (LULCC) and its effects on the natural environment are important in policy decision making for sustainable environment. This study investigated and assessed the environmental impacts of artisanal and small-scale mining operations on environmental degradation resulting from such activities in selected host communities (Akoko Edo, Ijero and Ilesa). Vegetation, water, built-up expansion and land surface temperature dynamics were examined and analysed using appropriate indices for the years 1987, 2002 and 2017. A gradual decrease in the normalised difference vegetation index (NDVI) values was observed across Akoko Edo and Ijero Ekiti with a corresponding change in the highest NDVI values while Ilesa witnessed a higher NDVI value in 2017 relative to the previous years. The majority of the normalised difference water index (NDWI) values for 2017 appear to be above 0 in all the host communities. Mean land surface temperature (LST) values are in the order 24.63 °C (1986) < 25.26 °C (2002) < 26.32 °C (2017) for Ijero Ekiti study area while mean LST values are in the order 24.30 °C (1986) < 24.46 °C (2002) < 25.82 °C (2017) in Ilesa study area. Modified Normalized Difference Water Index (MNDWI) seemed a more reliable indicator as the index was able to enhance the water surfaces more clearly as indicated in the case of Akoko Edo study area. Due to its high heat capacity, high land surface temperatures were experienced over urban areas and uncultivated bare land during all the periods of study. The study showed that changes in land covers have affected the normal functioning of the habitats through urbanisation. Adequate natural resource management is therefore necessary to ensure sustainable development through effective policy formulation.
Mostrar más [+] Menos [-]Comparative toxicity assessment of in situ burn residues to initial and dispersed heavy fuel oil using zebrafish embryos as test organisms Texto completo
2021
Johann, Sarah | Goßen, Mira | Mueller, Leonie | Selja, Valentina | Gustavson, Kim | Fritt-Rasmussen, Janne | Wegeberg, Susse | Ciesielski, Tomasz Maciej | Jenssen, Bjørn Munro | Hollert, Henner | Seiler, Thomas-Benjamin
In situ burning (ISB) is discussed to be one of the most suitable response strategies to combat oil spills in extreme conditions. After burning, a highly viscous and sticky residue is left and may over time pose a risk of exposing aquatic biota to toxic oil compounds. Scientific information about the impact of burn residues on the environment is scarce. In this context, a comprehensive ISB field experiment with approx. 1000L IFO 180 was conducted in a fjord in Greenland. The present study investigated the toxicity of collected ISB residues to early life stages of zebrafish (Danio rerio) as a model for potentially exposed pelagic organisms. The toxicity of ISB residues on zebrafish embryos was compared with the toxicity of the initial (unweathered) IFO 180 and chemically dispersed IFO 180. Morphological malformations, hatching success, swimming behavior, and biomarkers for exposure (CYP1A activity, AChE inhibition) were evaluated in order to cover the toxic response on different biological organization levels. Across all endpoints, ISB residues did not induce greater toxicity in zebrafish embryos compared with the initial oil. The application of a chemical dispersant increased the acute toxicity most likely due to a higher bioavailability of dissolved and particulate oil components. The results provide insight into the adverse effects of ISB residues on sensitive life stages of fish in comparison with chemical dispersant application.
Mostrar más [+] Menos [-]Feasibility study of fluorescent lamp waste recycling by thermal desorption Texto completo
2021
Esbrí, José María | Rivera, Sofía | Tejero, José | Higueras, Pablo León
The proposed Minamata Convention ban on the use of fluorescent lamps at the end of 2020, with a consequent reduction in mercury (Hg) light products, is expected to produce large amounts of discarded fluorescent bulbs. In this context, the most effective recycling options are a thermal mercury recovery system and/or aqueous solution leaching (lixiviation) to recover rare earth elements (REEs). Due to the heterogeneous nature of these wastes, a complete characterization of Hg compounds in addition to a determination of their desorption temperatures is required for their recycling. The objective of this study is to assess the feasibility of a fast cost-effective thermal characterization to ameliorate recycling treatments. A pyrolysis heating system with a heat ramping capability combined with atomic absorption spectrometry makes it possible to obtain residue data with regard to the temperature ranges needed to achieve total Hg desorption. The major drawback of these heat treatments has been the amount of Hg absorbed from the residue by the glass matrices, ranging from 23.4 to 39.1% in the samples studied. Meanwhile, it has been estimated that 70% of Hg is recovered at a temperature of 437 °C.
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