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Study of the influencing factors of the blood levels of toxic elements in Africans from 16 countries
2017
Henríquez-Hernández, Luis Alberto | Luzardo, Octavio P. | Boada, Luis D. | Carranza, Cristina | Pérez Arellano, José Luis | González-Antuña, Ana | Almeida-González, Maira | Barry-Rodríguez, Carlos | Zumbado, Manuel | Camacho, Maria
Africa's economy is growing faster than any other continent and it has been estimated that the middle class in Africa now exceeds 350 million people. This has meant a parallel increase in the importation of consumer goods and in the implementation of communication and information technologies (ICT), but also in the generation of large quantities of e-waste. However, inadequate infrastructure development remains a major constraint to the continent's economic growth and these highly toxic residues are not always adequately managed. Few studies have been conducted to date assessing the possible association between socioeconomic development factors, including e-waste generation, and blood levels of inorganic elements in African population. To disclose the role of geographical, anthropogenic, and socioeconomic development determinants on the blood levels of Ag, Al, As, Be, Cd, Co, Cr, Hg, Ni, Pb, Sb, and V —all of them frequently found in e-waste—, an immigrant population-based study was made including a total of 245 subjects from 16 countries recently arrived to the Canary Islands (Spain). Women presented higher levels of blood elements than men, and Northern Africans (Moroccans) were the most contaminated. People from low-income countries exhibited significantly lower blood levels of inorganic elements than those from middle-income countries. We found a significant association between the use of motor vehicles and the implementation of information and communication technologies (ICT) and the level of contamination. Immigrants from the countries with a high volume of imports of second-hand electronic equipment, telephone and internet use had higher levels of inorganic elements. In general terms, the higher level of economic development the higher the blood levels of inorganic pollutants, suggesting that the economic development of Africa, in parallel to e-waste generation and the existence of informal recycling sites, have directly affected the level of contamination of the population of the continent.
Mostrar más [+] Menos [-]Global change impacts on large-scale biogeographic patterns of marine organisms on Atlantic oceanic islands
2018
Ávila, Sérgio P. | Cordeiro, Ricardo | Madeira, Patrícia | Silva, Luis | Medeiros, Antonio | Rebelo, Ana C. | Melo, Carlos | Neto, Ana I. | Haroun, Ricardo | Monteiro, António | Rijsdijk, Kenneth | Johnson, Markes E.
Past climate changes provide important clues for advancement of studies on current global change biology. We have tested large-scale biogeographic patterns through four marine groups from twelve Atlantic Ocean archipelagos and searched for patterns between species richness/endemism and littoral area, age, isolation, latitude and mean annual sea-surface temperatures. Species richness is strongly correlated with littoral area. Two reinforcing effects take place during glacial episodes: i) species richness is expected to decrease (in comparison with interglacial periods) due to the local disappearance of sandy/muddy-associated species; ii) because littoral area is minimal during glacial episodes, area per se induces a decrease on species richness (by extirpation/extinction of marine species) as well as affecting speciation rates. Maximum speciation rates are expected to occur during the interglacial periods, whereas immigration rates are expected to be higher at the LGM. Finally, sea-level changes are a paramount factor influencing marine biodiversity of animals and plants living on oceanic islands.
Mostrar más [+] Menos [-]Recovery of macrobenthos in defaunated tropical estuarine sediments
2011
Botter-Carvalho, Mônica L. | Carvalho, Paulo V.V.C. | Santos, Paulo J.P.
In the estuarine environment, hypoxia and/or anoxia have become a major cause of benthic defaunation and are strongly associated with increased eutrophication. Mesoscale field experiments were carried out to examine the recolonization and recovery time of macrobenthos after defaunation. Azoic sediments were achieved by covering four areas with polyethylene sheeting. Temporal changes and depth distribution of macrobenthos within the defaunated sediments were compared with those in undisturbed natural sediments at the same site. Within 3days, annelids appeared as the first immigrants. After 153days, the process of recovery had not yet been completed in terms of species richness. Whereas diversity and evenness showed no significant differences between treatments during the entire experiment, multivariate analyses proved that differences between treatments were still significant 93days after the start of the experiment.
Mostrar más [+] Menos [-]The new potential invader Linopherus canariensis (Polychaeta: Amphinomidae) in a Mediterranean coastal lake: Colonization dynamics and morphological remarks
2011
Cosentino, A. | Giacobbe, S.
The newly introduced polychaete Linopherus canariensis Langerhans, 1881 was found in the Lake of Faro (NE Sicily), during a study comparing the macrobenthos in artificial modules with a neighboring sandy bottom assemblage. Of a total of 4465 specimens, almost 6% showed morphological variation related to branchial turfs and mean body size. The sandy bottom exhibited an average density of 41.86indL⁻¹ and a wet biomass of 30.35mgL⁻¹, whereas the artificial substratum reached levels of 205.29indL⁻¹ and 318.44mgL⁻¹. The highest estimated immigration rate was 3.7indL⁻¹d⁻¹ (5.8mgL⁻¹d⁻¹). In the artificial microhabitat, 0.4% of the population showed mid-anterior fragmentation, with anterior- (2%), mid- (<1%) and posterior- (1%) regenerating lineages, which contributed significantly to the dispersion ability of this species. L. canariensis was a selective micro-deposit feeder, even under conditions of reduced sediments. Linopherus was found to be a new potential invader of stressed environments that is probably tied to the import of oysters.
Mostrar más [+] Menos [-]Bibliometric analysis of immigration and environmental degradation: evidence from past decades
2022
The aim of this paper is to examine immigration and environmental degradation using bibliometric analysis. This paper also analyzes sources of publication, authorship, citations, distributions publications and other bibliometric indicators. The study focuses on a total of 1372 articles published from 2000 to 2020. These articles were collected through an automated process from the Scopus database and later analyzed using techniques such as bibliometric indicators analysis, VOSviewer, and Perish or Publish. The research identified 991 articles from varieties of published sources. The topic of immigrants and environmental degradation has been an emerging topic since 1981. Starting in 2000, most of the scholars actively producing an articles pertinent to this topic. Most of the articles were published in journals, and English is the primary language of research. United States is the leading country in contributing the publications. Meanwhile, the most significant fields in which the sources were produced were environmental science, agricultural and biological sciences, arts and humanities and earth and planetary sciences. However, some limitations has been found. It has been suggested for future research, to lengthen this work to other databases, as well as bibliometric analyses of immigration and environmental degradation in developed and developing countries by adding a new keyword such as energy consumption and climate change. This paper aims to assess recent trends in the expansion of academic literature on immigration and environmental degradation using the bibliometric analysis method. Network visualization and bibliometric indicators are used in this paper to present the results.
Mostrar más [+] Menos [-]Multidimensional analysis of global climate change: a review
2021
Bandh, Suhaib A. | Shafi, Sana | Peerzada, Mohazeb | Rehman, Tanzeela | Bashir, Shahnaz | Wani, Shahid A. | Dar, Rubiya
Even though climate change involves much more than warming, it is the name given to a set of physical phenomena. It is a long-term change in weather patterns that characterises different regions of the world. The warming effect in the earth’s atmosphere has dramatically increased through the influence of some heat-taping gases emitted by various human activities, especially fossil fuel burning. The more the input of such gases, the more will be the warming effect in the coming times. Global climate change is already visible in various parts of the larger ecosystems like forests, fisheries, biodiversity, and agriculture; however, it is now also influencing the supply of freshwater, human health, and well-being. This paper reviews climate change drivers, its global scenario, major global events, and assessing climate change impacts. The most daunting problem of economic and ecological risks, along with the threats to humanity, is also discussed. The paper further reviews the species’ vulnerability to climate change and the heat waves and human migration vis-à-vis climate change. Climate change politics and coverage of climate change episodes in mass media is the special focus of this review that concludes with a few mitigation measures.
Mostrar más [+] Menos [-]Foreign direct investment amidst global economic downturn: is there a time-varying implication for environmental sustainability targets?
2021
Philip, Lucy Davou | Sertoglu, Kamil | Akadiri, Seyi Saint | Olasehinde-Williams, Godwin
Turkey attracted more foreign investment in a period when global foreign direct investment flows experienced a recession due to the USA-China trade war/tension coupled with structural issues within the EU nations. In this paper, the time-varying impact of foreign direct investment on environmental sustainability targets amidst global economic downturn was examined. To achieve this, a time-varying parameter approach, which adequately deals with potential parameter instabilities and nonlinearities, and effectively captures impact variations over time, was employed to investigate the impacts of increased foreign direct investment on environmental degradation amidst global economic downturn for the period 1970–2017. Results showed that the inflow of foreign direct investment (FDI), energy use, urbanization, and real income has led to environmental problems in Turkey. It is thus recommended that the government does the following: (i) enact policies that emphasize green FDI inflows, (ii) enforce tighter environmental policies that deter the immigration of dirty production processes,(iii) engage in mixed and country-specific environmental policies in combating pollution, (iv) ensure domestic investors to adhere strictly to the nation’s environmental policies, and (v) enact policies to foster mutual cooperation and understanding between the local and foreign stakeholders in a manner that drives the use of energy-saving technologies in production activities and the use of renewables in place of fossil fuels to control environmental hazards for both the immediate and future generations.
Mostrar más [+] Menos [-]Spray pyrolysis synthesis and UV-driven photocatalytic activity of mesoporous Al2O3@TiO2 microspheres
2022
Vo, The Ky
Mesoporous microspheres of Al₂O₃@TiO₂ were effe ctively and rapidly prepared by the sol–spray pyrolysis (SP) method. Ultrasonic-induced droplets containing titania sol, boehmite sol, and citric acid (CA) were pyrolyzed to γ-Al₂O₃-incorporated anatase TiO₂ microspheres. The SP-derived Al₂O₃@TiO₂ microspheres exhibited higher porosity and lower bandgap energy than pure TiO₂ and commercial P25. The TiO₂ microspheres incorporated with 5 wt% amorphous γ-Al₂O₃ efficiently removed tetracycline (TC) after 60 min of pre-adsorption and 140 minutes of UV illumination (removal efficiency ~ 91%, surpassing those of pure TiO₂ and commercial P25). Introducing amorphous γ-Al₂O₃ into the anatase TiO₂ matrix created a synergetic effect that enhanced the accumulation of TC onto the catalyst surface; meanwhile, the formation of defective heterojunctions favored the separation and immigration of the photo-generated holes and electrons. In a reaction mechanism analysis, h⁺ and O₂•‾ radicals were identified as the main instigators of TC photooxidation. Furthermore, the SP-derived Al₂O₃@TiO₂ microspheres demonstrated good stability and renewability in durability tests. The study provides a simple and scalable method for manufacturing Al₂O₃-decorated TiO₂ microspheres with improved adsorption and photocatalytic performance.
Mostrar más [+] Menos [-]Is There Detectable Long-term Depletion of Genetic Variation in Freshwater Fish Species Affected by an Oil Spill?
2017
O. Agostinis, André | Dal Pont, Giorgi | Horodesky, Aline | Pie, Marcio R. | Ostrensky, Antonio
Oil spills might lead to severe environmental impacts to the affected fauna, disrupting local food webs, and causing mass mortality in many species. However, little is known about long-term impacts of oil spills, or even if such impacts can be detectable after several generations. In this study, we investigate the genetic variability of three freshwater species—Mimagoniates microlepis (Characiformes: Characidae), Scleromystax barbatus (Siluriformes: Callichthyidae), and Phalloceros harpagos (Cyprinodontiformes: Poeciliidae)—in rivers that were affected by a large oil spill in the state of Paraná, southern Brazil, on February of 2001. Samples were obtained from nine different locations, such that rivers that were directly affected by the oil spill could be compared with similar rivers in the same region that were unaffected. A fragment of the cytochrome C oxidase subunit I mitochondrial gene was sequenced from each specimen, and the level of genetic variability was assessed. Based on estimates of haplotype and nucleotide diversity, no impact of the oil spill could be detected in impacted rivers. These results suggest that fish populations in the region showed resilience to the pollutant, such that immigration from other locations was able to reestablish levels of genetic variability comparable to those of unimpacted rivers.
Mostrar más [+] Menos [-]Urban transformation of a metropolis and its environmental impacts : A case study in Shanghai
2012
Tian, Zhan | Cao, Guiying | Shi, Jun | McCallum, Ian | Cui, Linli | Fan, Dongli | Li, Xinhu
PURPOSE: The aim of this paper is to understand the sustainability of urban spatial transformation in the process of rapid urbanization, and calls for future research on the demographic and economic dimensions of climate change. Shanghai towards its transformation to a metropolis has experienced vast socioeconomic and ecological change and calls for future research on the impacts of demographic and economic dimensions on climate change. We look at the major questions (1) to explore economic and demographic growth, land use and land-cover changes in the context of rapid economic and city growth, and (2) to analyze how the demography and economic growth have been associated with the local air temperature and vegetation. METHOD: We examine urban growth, land use and land-cover changes in the context of rapid economic development and urbanization. We assess the impact of urban expansion on local air temperature and vegetation. The analysis is based on time series data of land use, normalized difference vegetation index (NDVI), and meteorological, demographic and economic data. RESULTS AND DISCUSSION: The results indicate that urban growth has been driven by mass immigration; as a consequence of economic growth and urban expansion, a large amount of farmland has been converted to paved road and residential buildings. Furthermore, the difference between air temperature in urban and exurban areas has increased rapidly. The decrease of high mean annual NDVI has mainly occurred around the dense urban areas.
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