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Resultados 3221-3230 de 6,535
Metal concentration and health risk assessment of wild mushrooms collected from the Black Sea region of Turkey
2020
Sarikurkcu, Cengiz | Akata, Ilgaz | Guven, Gulsen | Tepe, Bektas
Mushrooms are rich sources of organic nutrients (especially proteins). However, they can excessively accumulate metals in their fruiting bodies that pose a risk to human health. The aim of this study was the determination of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn contents, daily intake, and health risk index values of some mushroom species collected from the eastern Black Sea region of Turkey (Arsin, Trabzon). The samples were collected from hazelnut gardens that are free from industrial pollution and have a low population density. As a result of elemental analysis, it was determined that the concentration ranges of Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn in the mushrooms were as follows: 0.29–9.11, 0.04–3.70, 0.01–8.29, 0.18–20.82, 3.1–79.8, 5.2–673.0, 14.9–752.0, 63.0–7769.0 mg/kg dry weight. Daily intakes of all the elements were found to be below the reference dose in Fistulina hepatica, Hydnum repandum, Macrolepiota procera, and Tapinella atrotomentosa. Amanita caesarea, Agrocybe praecox, Amanita vaginata, Cantharellus cibarius, Craterellus cornucopioides, Daedalea quercina, Gymnopus dryophilus, Ganoderma lucidum, and Infundibulicybe gibba were found to have high risk index values especially with respect to Cd, Co, and Pb. According to Pearson correlation analysis, the correlations between Fe–Mn (0.840, p < 0.01) and Pb–Ni (0.7540, p < 0.01) couples are significant.
Mostrar más [+] Menos [-]Barriers to implementing the strictest environmental protection institution: a multi-stakeholder perspective from China
2020
Mao, Wenxin | Wang, Wenping | Sun, Huifang | Luo, Dang
Increasingly severe environmental issues, especially those in developing countries such as China, drive the evolution of the environmental protection institution (EPI) to its strictest levels. However, the implementation of the strictest EPI still confronts various challenges and barriers, and the multi-stakeholder features of EPI determine these barriers are not independent of one another but rather present complex interactive relationships. This paper identifies the barriers to implementing China’s EPI from four aspects of environmental legal, economic, regulatory, and public participation institutions. A variable precision rough DEMATEL approach is proposed to visualize the causal relationships and intensities among barriers from the similarities and differences in perspectives of stakeholders from the government, company, and public levels. The obtained causal interactive mechanism among barriers highlights the need to prioritize the improvement of environmental policy assessment, and the concrete measures in policies or plans should be integrated into legislation to ensure they are mutually supportive early. The non-substantive contributions achieved by China’s public participation in environmental protection reveal prejudices that the public is often regarded as a supporter or spectator by both government and company groups, which makes the transparent environmental information disclosure, transfer and feedback into an effective mediation among stakeholders. Comprehensive coordination and feedback mechanisms including source prevention, process control, and severe punishment for consequences while enhancing linkages among stakeholders are put forward to overcome barriers and help implement the strictest EPI.
Mostrar más [+] Menos [-]The role of tourism and renewable energy in testing the environmental Kuznets curve in the BRICS countries: fresh evidence from methods of moments quantile regression
2020
Aziz, Noshaba | Mihardjo, Leonardus WW | Sharif, Arshian | Kittisak Jermsittiparsert,
BRICS are among the rising nations which drive economic growth by excessive utilization of resources and resulting in environment degradation. Although there is bulk of research on environmental Kuznets curve (EKC), very limited studies explored the scope in context of tourism in BRICS countries. So this research is conducted to explore the association of tourism, renewable energy, and economic growth with carbon emissions by using annual data of BRICS countries from the year 1995 to 2018. By using the recent approach of method of moments quantile regression (MMQR), the finding shows that tourism has stronger significant negative effects from 10th to 40th quantile while the effects are insignificant at remaining quantiles. Furthermore, an inverted U-shape EKC curve is also apparent at all quantiles excluding 10th and 20th quantiles. For renewable energy, the results are found negatively significant across all quantiles (10th–90th) which claim that CO2 emission can be reduced by opting renewable sources. Hence, the empirical results of the current study provide insights for policymakers to consume renewable energy sources for the sustainable economic growth and solution of environmental problems.
Mostrar más [+] Menos [-]The impact of macroeconomic and financial development on carbon dioxide emissions in Pakistan: evidence with a novel dynamic simulated ARDL approach
2020
K̲h̲ān̲, Muḥammad ʻImrān | Teng, Jian Zhou | Khan, Muhammad Kamran
This paper has empirically explored the impact of macroeconomic and financial development on CO₂ emissions by utilizing a novel dynamic simulated ARDL model for annual time series data from 1982 to 2018 for Pakistan. The results of a novel dynamic simulated ARDL disclosed that the growth of stock market, FDI, economic growth, and consumption of oil wield a positive impact on CO₂ emission, while domestic credit exerts a negative effect on CO₂ emission both in the short and the long run in Pakistan. The stock market development and domestic credit wield a significant influence on carbon dioxide emission in Pakistan both in the long and the short run. FDI exerts significant impact only in the long run, while economic growth and consumption of oil wield significant impact only in the short run on CO₂ emission in Pakistan. This study opens up new visions for the economy of Pakistan to sustain financial and economic growth by protecting environment from pollution through its efficient national environmental policy, fiscal policy, and monetary policy.
Mostrar más [+] Menos [-]A Single Digestion Procedure for Determination of Major, Trace, and Rare Earth Elements in Sediments
2020
Carvalho, Lina | Reis, Ana T. | Soares, Eugênio | Tavares, César | Monteiro, Rui J. R. | Figueira, Paula | Henriques, Bruno | Vale, Carlos | Pereira, Eduarda
The simultaneous determination of major, trace, and rare earth elements in sediments requires the development of specific procedures to prevent interferences. A single digestion method adapted from the EPA method 3051A is proposed for the quantification of 42 elements in sediments by inductively coupled plasma techniques associated with optical emission spectroscopy (ICP-OES) and mass spectrometry (ICP-MS). A combination of different acids and microwave-assisted acid extraction following hot plate extraction was tested. Evaluation of applicability range, linearity, limits of detection and quantification, selectivity, repeatability, intermediate precision, and trueness showed the accurate determination of all elements. Selectivity, precision, and trueness values were below the criteria established by the laboratory. The applicability of the proposed method was tested in real sediment samples. For each element, difference between duplicates was lower than the corresponding repeatability limit, with the coefficients of variation ranging between 1.7 and 14%. These results point to the usefulness of this method in multi-element determination of major, minor, trace, and REE in sediment samples, showing its applicability in environmental studies related, namely to sediment characterization, monitoring programs, assessment of environmental impacts, sediment provenance, and post-depositional mechanisms. Graphical abstract
Mostrar más [+] Menos [-]Quality of Natural Waters Surrounding Campo Mourão, State of Paraná, Southern Brazil: Water Resources Under the Influences from Urban and Agricultural Activities
2020
Mendes, Sabrina Altmeyer | Gonçalves, Éderson Vecchietti | Frâncica, Letícia Scala | Correia, Leonardo Borges Coleto | Nicola, João Victor Nunes | Pestana, Ana Caroline Zago | da Silva Medeiros, Flávia Vieira | de Souza, Wyrllen Everson | Ineu, Rafael Porto | Peron, Ana Paula
The Campo and Km 119 rivers are sources of irrigation and water supply for the city of Campo Mourão, State of Paraná, Southern Brazil. However, these rivers are under the influence of agricultural and urban activities, which compromise the quality of their waters. The present study evaluated the waters of these rivers in the vicinity of this municipality in two different hydrological periods of 2018 for physical and chemical parameters and potential cytotoxic, genotoxic, and toxic effects. Among the eight sites, in the dry and rainy periods, P1, P2, P3, P4, and P6—sites surrounded by agricultural activities, with nearby residences and with low and/or reduced riparian forest—presented a low concentration of dissolved oxygen and high concentration of nitrite, phosphate, and chlorine. The waters of P1, P2, P3, P4, and P6, in the two samplings, were cytotoxic to the root meristem cells of Allium cepa at 24 and 48 h of exposure, and toxic to Artemia salina nauplii at 24 h of exposure, with LC₅₀ < 100 ppm. The results characterize water contamination by pesticides and urban waste from stormwater drains and runoff from the urban area. Therefore, waters of the Campo and Km 119 rivers in the vicinity of the city of Campo Mourão demonstrate the potential to cause adverse effects to man and the aquatic ecosystem. These results represent an alert to the public authorities of Campo Mourão and the State of Paraná regarding the need to inspect the anthropic activities in that city in the vicinity of these rivers, and in the implementation of a management plan for the replacement of riparian forests in places close to urban area, in order to preserve the health of the population and the ecosystems that depend on these water resources.
Mostrar más [+] Menos [-]Biofertilizer Application on Corn (Zea mays) Increases the Productivity and Quality of the Crop Without Causing Environmental Damage
2020
de Matos Nascimento, Andressa | Maciel, Alyne Martins | Silva, Jonathas Batista Gonçalves | Mendonça, Henrique Vieira | de Paula, Vanessa Romário | Otenio, Marcelo Henrique
This study evaluated the effect of applying biofertilizer in the soil on the cultivation of corn. Different doses of biofertilizer associated with chemical fertilizer were applied in the soil to meet the plants’ nutritional demand. Four months after sowing, plant samples were collected and evaluated, by measuring the height and productivity of biomass, dry matter, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), and nitrogen (N). Soil samples were also collected to measure the concentrations of macronutrients, base saturation, and exchangeable acidity. The biofertilizer application did not alter the levels of dry matter, NDF, ADF, CP, and N in the plants, or the concentrations of nitrogen, phosphorus, magnesium, and copper in the soil. Besides this, the largest average values of the plant heights and levels of potassium in the soil were found in the treatment with the highest biofertilizer dose. Notably, there was a significant increase in the quantity of fresh and dry matter in the treatments that received biofertilizer in comparison with the controls. The results obtained indicated the potential of substituting conventional fertilization with fertirrigation using biofertilizer, an alternative procedure that can help reduce the environmental impacts caused by dairy farming, regarding the release of wastewater into watercourses.
Mostrar más [+] Menos [-]Ecological risk evaluation and source apportionment of heavy metals in park playgrounds: a case study in Xi’an, Shaanxi Province, a northwest city of China
2020
Guo, Bin | Su, Yi | Pei, Lin | Wang, Xiaofeng | Zhang, Bo | Zhang, Dingming | Wang, Xiaoxia
Park playgrounds recently are suffering serious heavy metals contamination in China. It is urgent to assess the ecological risk and identify the sources for heavy metals. A total of 111 topsoil samples were collected from four park playgrounds in Xi’an, and the X-ray fluorescence (XRF) instrument was used to measure the concentrations of heavy metals including chromium(Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), manganese (Mn), and cobalt (Co), respectively. Ecological risk ([Formula: see text]) and potential ecological risk index (RI) were introduced to determine the pollution level and ecological risk, and the absolute principal component score-multiple linear regression (APCS-MLR) model was implemented to identify the sources for heavy metals. The main results were as follows. (1) Except As, the mean concentrations of measured heavy metals of four park playgrounds surpassed the soil background values of Shaanxi Province. (2) In each park playground, the [Formula: see text] was below a “low” risk level ([Formula: see text]=10) for Cr, Ni, Zn, As, and Mn; Cu was between a “moderate” and “considerable” risk level; Pb was between a “low” and “moderate” risk level; and [Formula: see text] was between a “considerable” and “high” risk level for Co. Besides, the RI index was on a “high” risk level (120 < RI < 240) with an obvious spatial distinction. (3) The anthropogenic factors were the main sources for heavy metals, and mixed sources and natural sources were considered as the minor sources for metals. (4) The sources contributions for Co had obvious spatial heterogeneity in each park situated in four different urban planning districts.
Mostrar más [+] Menos [-]Experimental Exposure of Lumbricus terrestris to Microplastics
2020
Baeza, Carolina | Cifuentes, Camila | González, Patricia | Araneda, Ana | Barra, Ricardo
The effects of microplastic exposure in aquatic organisms have been widely reported. Nonetheless, there is limited evidence of the effects of exposure in soil systems. Thus, the objective of this study was to evaluate the effects of microplastic exposure using as a bioindicator the species Lumbricus terrestris, exposed to different concentrations of microplastic (2.5%; 5%, and 7% w/w). Avoidance bioassays were carried out for 48 h in soil with and without microplastic; the gastrointestinal tract—crop/gizzard, foregut, and midgut—was dissected and acetylcholinesterase (AChE) was used as a biomarker of neurotoxicity stress. In parallel, bioassays of microplastic ingestion were carried out, and after 48 h of initiating the ingestion assay, using a stereo and fluorescence microscope, the microplastic distribution was observed in the different earthworm segments. The results obtained in the avoidance assay indicated a lack of preference for either soil type; however, upon moving, the earthworms lost surface mucus, resulting in burns and lesions on their bodies, which were reflected in the increase in AChE enzyme levels, which was not directly related to microplastic ingestion, but rather likely acts as an external physical stress agent. The results of the ingestion bioassay showed that microplastic was present in all the earthworm segments, with a higher number of particles in the hindgut. The Lumbricus terrestris did not distinguish microplastics from soil particles, and given the high exposure concentrations, microplastics produced physical lesions on the mucus membranes of earthworms. Lumbricus terrestris showed to be a suitable bioindicator for testing the exposure to microplastic contamination in soil.
Mostrar más [+] Menos [-]Non-resident and resident patents, renewable and fossil energy, pollution, and economic growth in the USA
2020
Ben Youssef, Slim
The main objective of this paper is to estimate the impact of foreign research and development (R&D) spillovers on pollution and renewable energy consumption (RE). We choose as proxies for R&D and for foreign R&D spillovers, resident patents (RP) and non-resident patents (NRP), respectively. We use annual data for the USA spanning the period 1980–2016. We show the presence of a long-run relationship between NRP, RP, RE, fossil energy consumption (FE), net energy imports (NEI), gross domestic product (GDP), and carbon dioxide (CO₂) emissions. There are long-run unidirectional Granger causalities running from all considered variables to economic growth. There are short-run unidirectional causalities running from NEI to all considered variables except RP and GDP, from GDP to RP and RE, from FE to RE, and from carbon emissions to RE. By using the autoregressive distributed lag approach, several long-run elasticities are evaluated. In particular, RP increases carbon emissions, whereas NRP reduces it. Both RP and NRP have a positive impact on RE and GDP. RP and NRP seem to be complementary activities, and RE reduces NEI. Therefore, the US authorities should encourage the use of NRP because of their beneficial effect on pollution, home innovation, renewable energy consumption, and economic growth.
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