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1.
J Insect Sci ; 20(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31925424

RESUMO

Urbanization has a significant impact on abiotic and biotic factors in nature. We examined the morphometric characters of four carabid species (Abax parallelepipedus, Carabus scheidleri, Carabus violaceus, and Pterostichus oblongopunctatus) along urbanization gradients in and around the cities of Vienna (Austria) and Debrecen (Hungary). We found significant differences among urban, suburban, and rural areas in the parameters of antennomers, the maxillary palpus, the labial palpus, and the length of the tibia and the elytra of the carabids studied. We also found significant differences between males and females based on the parameters of antennomers, the maxillary palpus, the labial palpus, the femur, and the elytra. An interaction between urbanization and sex was found in the case of antennomers, the maxillary palpus, the labial palpus, the femur, and the elytra. Our findings suggested that in the cases of species from Carabini tribus the parameters of antennomers, the maxillary palpus, and the elytra could be useful for assessing the effects of urbanization because these morphometric characters responded sensitively to the environmental stress, whereas the most useful parameters are those of antennomers and the tibia for the species of Pterostichini tribus. Our findings also revealed that females are more sensitive to environmental stress than males.


Assuntos
Besouros/anatomia & histologia , Urbanização , Animais , Áustria , Cidades , Feminino , Hungria , Masculino , Especificidade da Espécie
2.
Chemosphere ; 238: 124566, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31446272

RESUMO

How far-reaching is the influence of the urban area over the mineral composition of the Russula cyanoxantha mushroom? We studied the metal uptake behavior of this fungus relying on the soil properties. We sampled mushroom and soil from six forests according to an urbanization gradient, and two city parks in Cluj-Napoca (Romania). The elements were quantified using inductively coupled plasma - optical emission spectroscopy (ICP-OES). The concentrations of some elements differed significantly (p < 0.05) in the samples from the city (0.39 ±â€¯0.35 mg kg-1 for cadmium (Cd), 0.40 ±â€¯0.19 mg kg-1 for chromium (Cr), 69.1 ±â€¯29.9 mg kg-1 for iron (Fe), 10.9 ±â€¯1.3 mg kg-1 for manganese (Mn), 0.76 ±â€¯0.45 mg kg-1 for titanium (Ti) compared with the samples from the forests (3.15-14.1 mg kg-1 Cd, < 0.18 mg kg-1 for Cr, 22.6-34.5 mg kg-1 for Fe, 15.9-19.1 mg kg-1 for Mn, 0.19-0.36 mg kg-1 for Ti). We observed a definite negative trend in the mineral accumulation potential of this fungus along the urbanization gradient. The fungus turned from a cadmium-accumulator to a cadmium-excluder. This highlights a positive environmental influence of the urbanization over the toxic metal uptake of R. cyanoxantha. The hypothesis, that the urban soil pollution would increase the metal content of the mushroom was disproved. The possible explanation might be the elevated carbonate content of the urban soil, which is known to immobilize the metals in the soil.


Assuntos
Agaricales/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Cádmio/análise , Cromo/análise , Cidades , Ferro/análise , Manganês/análise , Romênia , Urbanização
3.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3303-3315, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621216

RESUMO

Urban greenspace, which serves as a place for residents to connect with nature and relax, provides important ecosystem services. Access to greenspace is often related to the socio-economic characteristics of residents, which received a lot attention from researchers and practitioners. Previous studies have mostly focused on single city to analyze the spatial relationship between greenspace distribution and residents' characteristics. We conducted a meta-analysis with global studies. The objectives were to classify findings from different cases and investigate the impacts from the location of research area, indicator and analytical method, and summarized major factors influen-cing the relationship between greenspace distribution and residents' characteristics. The results showed that more than half of the cases (58.2%) found that the socially advantaged population benefited more from greenspace. About a quarter cases (25.4%) revealed the opposite, that was, the disadvantaged population benefited more from greenspace. The remaining case studies (16.4%) did not find significant correlation between them. The studies reviewed here were diverse in terms of scale, indicator selection, and analytical method. Overall, we found no connection between finding and the choice of scale/indicator/analytical method. The reviewed case studies were mostly conducted in cities of western countries, which differed in their development trajectories and urban characteristics from cities in China. To understand association between urban greenspace and residents' characteristics in China, we urged to carry out more local studies, which would potentially provide scientific evidence for building sustainable cities during rapid urbanization.


Assuntos
Ecossistema , Urbanização , China , Cidades , Fatores Socioeconômicos , População Urbana
4.
J Environ Manage ; 252: 109668, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31604185

RESUMO

Agriculture land in Egypt represents only 3.8% of the total area. The Nile delta provides two thirds of Egypt's agriculture land, but is threatened by urban sprawl. The paper aims to quantify urban expansion over a 45 year period using 6 time points from 1972 to 2017, and its impacts on agricultural potential, soil organic carbon stocks, and implications for water use. The study used multi-temporal satellite data and remote sensing techniques (Maximum Likelihood supervised classification, and NDVI), soil sampling and analysis, data on water irrigation, and agroecological system and ecosystem services model (MicroLEIS, InVEST) to assess the effects of land use change. Urban area increased by a factor of 5, from 452 km2 in 1972 to 2644 km2 in 2017. The greatest losses occurred to the fertile Vertic Torrifluvent soils on the older delta, which lost 1734 km2. Soil organic carbon (0-75 cm depth) lost as a result of soil sealing from urbanisation rose from 25,000 to 141,000 Mg C over the 45 years. As a result of increased pressure on delta land, agriculture expanded into the higher desert areas outside the delta, on marginal land sustained by intensive fertiliser use and irrigation, which in turn puts pressure on water use. Therefore, rapid urban expansion has resulted in a loss of soil carbon and a shift in agriculture from fertile soils to marginal soils, requiring more capital inputs, which is ultimately less sustainable. Modelling suggested that soil management improvement could make better use of fertile soils within the Delta currently affected by high salinity and poor drainage. Future planning should encourage urban expansion on the less fertile soils outside of the delta, while improving suitability of existing agricultural land and minimising land degradation within the delta.


Assuntos
Solo , Urbanização , Agricultura , Carbono , Ecossistema , Egito
5.
BMC Infect Dis ; 19(1): 771, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481053

RESUMO

BACKGROUND: Although worldwide measles elimination achieved great progress for decades, outbreaks were still reported in certain countries. This study describes the epidemiologic features of a substantial measles outbreak in an office building in Beijing and explores control strategies in a crowded city. METHODS: We performed descriptive analyses of data on demographic characteristic, laboratory testing and epidemiological information. RESULTS: From February 25 to March 28, 2016, 43 outbreak-related measles cases occurred in an office building in Beijing. The total crude attack rate was 1.20% in the building. The age range of patients was 23 to 45 years old, of whom 30 (69.8%) were migrants and 5 (11.6%) were vaccinated but without documentation. The attack rate of the department and the company of the source case was 22.73 and 11.86%, respectively. The attack rate in the building was 1.78%, except for the commercial center on the lower floors, which was 0.34%. Of the 43 measles cases, only 19 cases (53.5%) were reported by hospitals through the National Notifiable Disease Reporting System (NNDRS), and the rest were found through active surveillance. Outbreak response immunization was conducted for 6216 persons. CONCLUSIONS: Office buildings in crowded metropolis are prone to large-scale measles outbreaks, and require a rapid outbreak response. Early Outbreak response immunization and active surveillance are important strategies to control outbreaks such as the one reported herein.


Assuntos
Aglomeração , Surtos de Doenças , Sarampo/epidemiologia , Adulto , Pequim/epidemiologia , China/epidemiologia , Surtos de Doenças/prevenção & controle , Feminino , Hospitais , Humanos , Incidência , Masculino , Sarampo/prevenção & controle , Pessoa de Meia-Idade , Urbanização , Vacinação/normas , Vacinação/estatística & dados numéricos , Adulto Jovem
6.
Environ Monit Assess ; 191(10): 614, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31489514

RESUMO

Globally, rivers and streams are experiencing declining water quality. Anthropogenic activities largely contribute to surface water pollution. Understanding human-induced influence on river water quality remains a challenge owing to spatiotemporal variations. In this study, we assessed the influence of various land uses (LU) on 16 water quality parameters of the Mun River, a tributary of the Mekong River, at different scales. Water quality was statistically analyzed both spatially and temporally (1995-2010). Seasonal and annual effect of LU on water quality was evaluated at buffer zone scale and sub-basin scale (i.e., catchment scale) using multiple regression analysis. The result showed that urban LU extensively adds to the nutrient concentration [i.e., total phosphorus (TP), ammonia nitrogen (NH3-N)] followed by agriculture LU at the sub-basin scale. Site-specific variability of TP is explained by urban LU and biological oxygen demand (BOD) by agriculture LU at the 5-km buffer in Upper and Middle Mun whereas at Lower Mun, the 20-km buffer explains the variability of suspended solids (SS) and total suspended solids (TSS), suggesting a more localized effect on the parameters upstream. The high concentration of parameters was noted in the dry season whereas the opposite was true for fecal coliform bacteria (FCB), SS, and TP. The maximum parameter concentration of NH3-N, FCB, and total coliform bacteria exceeds the permissible surface water quality standards of the Pollution Control Department (PCD) of Thailand in all three sub-basins. The study suggests the need for multi-scale interventions and effective pollution control measures focusing on nutrient, pathogenic bacteria, and solids pollution to improve the river water quality of large river basin.


Assuntos
Agricultura , Monitoramento Ambiental , Rios , Urbanização , Qualidade da Água , Humanos , Rios/química , Rios/microbiologia , Estações do Ano , Tailândia , Clima Tropical , Poluição da Água/análise , Qualidade da Água/normas
7.
BMC Ecol ; 19(1): 40, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533798

RESUMO

BACKGROUND: Urbanisation has been shown to influence many aspects of animal vocal communication. Much attention has been paid to anthropogenic noise, which is often described as one of the most challenging disturbances for urban dwellers. While a large body of literature describes associations between vocal behavior of avian populations and background noise level, most of these studies were conducted on species with relatively simple songs and small repertoire sizes. This study focuses on the song thrush, Turdus philomelos, a common Eurasian songbird with a complex singing style and large syllable repertoire. Our objective was to determine whether frequency, repertoire and temporal organisation of song parameters vary between birds inhabiting urban and adjacent forest habitats in which ambient noise levels differ. RESULTS: Songs of urban males were found to be more complex than in conspecifics from natural forest populations. Urban dwellers possessed greater syllable repertoires and repeated syllable sequences more often. In addition, they used a smaller proportion of whistles and a higher proportion of twitter syllables when singing compared to the nonurban males. Moreover, we found significant differences in the minimum and peak frequency of the whistle syllable between studied populations. CONCLUSIONS: These findings may be an example of adaptation of acoustic communication in noisy urban environments, but we also discuss other possible explanations. We emphasize the need for further investigation into the relationships between birdsong and habitat characteristics, male quality, population density and ambient noise level in populations occupying urban and nonurban habitats.


Assuntos
Aves Canoras , Animais , Ecossistema , Masculino , Ruído , Urbanização , Vocalização Animal
8.
J Environ Manage ; 251: 109553, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539701

RESUMO

In recent decades, urban developments along rivers have experienced high flooding risks, elevated by increasing urbanization. Due to the expansion of urban areas, flood mitigation strategies must rely on nonstructural flood management policies. This study evaluated the impacts of pluvial floods considering fluvial flooding effects through field surveys and numerical model simulations. Nonstructural flood protection measures are provided by establishing warning water levels based on variant scenario simulations. The results reveal that the aggravated drainage system overflow induced by elevated river water is significant when considering river flooding effects. As a result, current drainage systems have failed to meet the designed flood protection standards, indicating the need to produce potential inundation maps and to establish warning water levels. To prevent the main evacuation route of each settlement from being blocked due to flooding, the proposed warning water levels support timely and effective evacuations. Public community centers and schools in noninundation areas near settlements were identified as possible shelters based on the proposed warning water levels and inundation maps. We conclude that although the riverside areas without dike protection could sustain natural environments and landscapes, they must incorporate nonstructural flood protection measures. At the same time, it must be considered that river flood levels may reduce urban drainage capacity.


Assuntos
Inundações , Rios , Urbanização
9.
BMC Public Health ; 19(1): 1082, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399049

RESUMO

BACKGROUND: Active transportation (AT), independent mobility (IM), and outdoor time are promising ways to increase children's physical activity. However, in order to create interventions to increase those forms of physical activity, it is important to understand the relationships between area-level socioeconomic status (SES) and type of urbanization with AT, IM, outdoor time, and physical activity, and this was the aim of the study. METHODS: One thousand six hundred ninety-nine children in grades 4 to 6 (mean age: 10.2 ± 1.0 years) from three Canadian regions participated. AT, IM, and outdoor time were assessed using questionnaires and physical activity was measured using the SC-StepRX pedometer. Area-level SES was assessed using the median household income of the census tract in which the school was located and type of urbanization was determined for each school using standardized procedures. Generalized linear and general linear mixed models were used to examine the relationships. RESULTS: Area-level SES and the type of urbanization were generally not related to AT, IM, or physical activity for either gender. However, we observed that both boys and girls living in lower SES areas had decreased odds of spending > 2 h outdoors on weekend days compared to their peers from higher SES areas. Girls living in suburban or rural areas were more likely to spend > 2 h outdoors on weekdays compared to their urban counterparts. CONCLUSIONS: AT, IM, and physical activity are generally not associated with area-level SES or the type of urbanization in this sample of Canadian children. The finding regarding outdoor time showing that both boys and girls of lower SES areas had decreased odds of spending > 2 h outdoors on weekends compared to their peers from higher SES areas suggest that additional efforts should be implemented to offer outdoor play opportunities in lower SES areas.


Assuntos
Exercício/fisiologia , Liberdade , Áreas de Pobreza , Transportes/estatística & dados numéricos , Urbanização , Adolescente , Canadá , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários , Fatores de Tempo
10.
Environ Monit Assess ; 191(9): 551, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399777

RESUMO

The last couple of decades have seen remarkable spatial growth in the urban areas of developing countries. The process of urbanization is directly linked with land transformation which can be an effective way to monitor the spatio-temporal pattern of urban growth. New Delhi, the capital city of India has experienced a large-scale urban growth during the last decade. In order to identify the pattern of urban expansion in and around Delhi, the present study aims to assess the process of land transformation using multi-temporal Landsat datasets (1977-2014). The areas under various land use and land cover (LULC) extracted by support vector machine (SVM) hybrid classifier reveal asignificant change in the LULC pattern of the area. A good agreement was found between field-based information and maps generated using satellite images (kappa ≥ 0.84). Land transformation maps indicate rapid growth of few urban centres located outside Delhi National Capital Territory (NCT), like Gurgaon, Gautam Buddha Nagar, Faridabad and Ghaziabad. These centres have been remarkably expanded because of transformation of agricultural and vegetated lands. However, green patches within the city have not been affected by the consequences of urbanization. In tune with the rapid urbanization in the periurban centres of Delhi, the Moderate Resolution Imaging Spectro-radiometer (MODIS)-derived land surface temperature (LST) images revealed significant change in the level of LST. The inter-relationship of impervious surface fraction (ISF) and LST proves a good agreement between them. The increasing trend observed in the long-term (1987-2011) summer temperature data obtained from India Meteorological Department (IMD) indicates the rise of mean summer temperature in the last few decades. Land transformation along with rapid urbanization especially in the periurban areas of Delhi NCT played a key role in the increasing trend of surface temperature.


Assuntos
Monitoramento Ambiental/métodos , Temperatura Alta , Urbanização , Agricultura , Cidades , Índia , Imagens de Satélites , Temperatura Ambiente
11.
Environ Monit Assess ; 191(9): 532, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375933

RESUMO

Macajalar Bay in the southern Philippines has become an attractive thoroughfare with recent developments, rendering anthropogenic input to the coastal waters. Expediting coastal resource management strategies necessitates the present study on coastal water characteristics. This was aided with distribution pattern and multivariate analyses for apportioning possible anthropogenic inputs. A total of 15 biophysicochemical characteristics were studied covering two municipalities (Opol and Jasaan) with six subcoastal communities in 2017. Data were all processed for Q test to eliminate outliers before distribution analyses using univariate (descriptive), inferential (t test, one-way ANOVA, Pearson correlation), and multivariate statistics (hierarchal cluster analysis (HCA) and principal component analysis (PCA)). Overall, higher concentrations were determined in the ecotourism site (Opol) than in the industrial site (Jasaan) as sampling months progressed except for oil and grease. Results for total coliform, fecal coliform, heterotrophic plate count (HPC), total suspended solids (TSS), chemical oxygen demand (COD), and oil and grease regardless of spatial-temporal variations exceeded the standards. Distribution pattern revealed variations selectively for pH, temperature, dissolved oxygen (DO), and oil and grease, indicating site-specific distribution. HCA and PCA results corroborated correlation matrices showing elevated concentrations in an ecotourism site (Opol) apportioned anthropogenic input mainly due to rural development and ecotourism. Likewise, in the industrial site (Jasaan), HCA and PCA results reflected possible anthropogenic input from rural development and industries. Overall, anthropogenic apportionment in the bay was influenced by rural development, ecotourism, and industries.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Atividades Humanas , Poluição da Água/análise , Análise da Demanda Biológica de Oxigênio , Análise por Conglomerados , Monitoramento Ambiental/estatística & dados numéricos , Análise Multivariada , Filipinas , Análise de Componente Principal , Temperatura Ambiente , Urbanização
12.
Environ Monit Assess ; 191(9): 539, 2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31377943

RESUMO

The externalities generated by disorderly urbanization and lack of proper planning becomes one of the main factors that must be considered in water resource management. To address the multiple uses of water and avoid conflicts among users, decision-making must integrate these factors into quality and quantity aspects. The water quality index (WQI), using the correlation matrix and the multivariate principal component analysis (PCA) and cluster analysis (CA) techniques were used to analyze the surface water quality, considering urban, rural, and industrial regions in an integrated way, even with data gaps. The results showed that the main parameters that impacted the water quality index were dissolved oxygen, elevation, and total phosphorus. The results of PCA analysis showed 86.25% of the variance in the data set, using physicochemical and topographic parameters. In the cluster analysis, the dissolved oxygen, elevation, total coliforms, E. coli, total phosphorus, total nitrogen, and temperature parameters showed a significant correlation between the data's dimensions. In the industrial region, the characteristic parameter was the organic load, in the rural region were nutrients (phosphorus and nitrogen), and in the urban region was E. coli (an indicator of the pathogenic organisms' presence). In the classification of the samples, there was a predominance of "Good" quality, however, samples classified as "Acceptable" and "Bad" occurred during the winter and spring months (dry season) in the rural and industrial regions. Water pollution is linked to inadequate land use and occupation and population density in certain regions without access to sanitation services.


Assuntos
Monitoramento Ambiental , Escherichia coli/crescimento & desenvolvimento , Poluição da Água/análise , Qualidade da Água/normas , Recursos Hídricos , Brasil , Análise por Conglomerados , Análise Multivariada , Nitrogênio/análise , Fósforo/análise , Análise de Componente Principal , Rios , Estações do Ano , Temperatura Ambiente , Urbanização
13.
Environ Monit Assess ; 191(9): 595, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463613

RESUMO

Runoff coefficient (RC) is one of the important parameters, which is often considered in surface runoff and peak flood discharge estimation methods in various projects of watershed management and flood control. However, the effect of variability of RC due to human-induced activities on hydrologic behavior of the watershed has not been adequately considered globally. Therefore, the present research was carried out using 18 hyetographs and their corresponding hydrographs during 1984 to 2012 after considering the existence of suitable Landsat 7 (ETM+ and TM) satellite images with corresponding storm events for the Amameh Watershed located in Tehran Province, Iran. The object-oriented classification method was used to derive land use maps from satellite images. Afterward, four time periods were determined based on mean and standard deviation of residential area variations. The temporal distribution pattern of RC was then derived using a ranking method. The one- and two-way analyses of variance were also used to investigate the effect of residential area and rainfall variables on RC. Relationships among residential area as well as rainfall variables as independent variables and mean RC storm-wise as dependent variable were then modeled using two and multiple linear regressions. The results showed that RCs reduced in order of third, second, fourth, and first quartiles with respective values of 42.4, 38.2, 15.8, and 3.6%. The results also showed that RCs in the second and first quartiles and in the third and fourth quartiles were non-significantly decreased and increased by increasing of residential area, respectively. So that the highest variations occurred in first quartile with slope of - 144%. The results further proved that rainfall amount, φ index, and residential area with respective standardized regression coefficients (ß) of 0.629, - 0.465, and - 0.108 had the highest controlling effects on RCs. The finding of the current research proved the temporal variability of RCs at storm scale with more determinant effectiveness of rainfall properties than urbanized interferences. It helps hydrologists and watershed mangers designate appropriate strategies leading to proper implementations of developmental projects.


Assuntos
Monitoramento Ambiental , Inundações/prevenção & controle , Urbanização , Movimentos da Água , Hidrologia , Irã (Geográfico) , Chuva , Imagens de Satélites
14.
Environ Pollut ; 254(Pt B): 113034, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465904

RESUMO

Bats are particularly suited as bioindicators of trace element pollution due to their longevity and their position in the trophic chain. In this study, the concentrations of ten non-essential trace elements (Al, As, Ba, Cd, Hg, Pb, Sb, Sr, Th, Tl) were determined in the tissues (whole body, skin-fur, skinned body, liver, kidney and bone) of lactant Tadarida teniotis from a nursery colony in Rome. A large number of bats from this nursery died before fledging and had bone deformities and fractures. The concentrations of non-essential trace elements in bone and whole body were also analysed in adult specimens of Miniopterus schreibersii from a colony located in a natural park in Northern Italy. In lactant T. teniotis, the Pb concentration decreased in the following order: bone>liver>skinned body>whole body>skin-fur>kidney, and exceeded the toxic threshold associated with negative effects reported for different mammalian species. The levels of the other non-essential trace elements were within a range indicative of low environmental contamination in both species. Significant interspecies differences (P < 0.05) were observed for concentrations of Pb and Ba, higher in the bones of T. teniotis, and of Cd, Hg and Sr, higher in the bones of M. schreibersii. In lactant T. teniotis, the different sources of Pb exposure, through inhalation and/or food, may represent a potential threat to the colony of this synanthropic European bat.


Assuntos
Quirópteros/metabolismo , Exposição Ambiental/análise , Oligoelementos/análise , Animais , Monitoramento Ambiental , Itália , Rim/química , Fígado/química , Mercúrio/análise , Roma , Oligoelementos/metabolismo , Urbanização
15.
Mar Pollut Bull ; 146: 427-434, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426177

RESUMO

To study the impact of rapid industrialization and urbanization in Guangxi Province on the coastal environment in recent years, seven metals (Hg, Cu, Pb, Cd, Cr, Zn and As) were investigated in the surface seawater and sediments of the northern Beibu Gulf. The levels of the metals were lower than in other regions in China, but Hg, Cu and Cd showed a significant increasing trend in both seawater and sediments over the past 20 years. Higher levels were consistently observed in the nearshore area, particularly in the northwest, which may be related to the rapid industrial development in coastal areas. Correlation and principal component analyses suggested that both terrestrial inputs and biological processes influenced the distribution of metals. In addition, the higher risk observed for Hg and Cu may be largely influenced by the increasing trend in these metals in the Beibu Gulf.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Água do Mar/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Urbanização
16.
Mar Pollut Bull ; 146: 574-583, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426195

RESUMO

The Caribbean Coast of Colombia has a flourishing plastic industry with weak and insufficient waste management policies and practices, leading to plastic pollution along its touristic beaches. In this work, primary and secondary microplastics (MPs) were surveyed at four different locations along the Colombian Caribbean Coast. Primary microplastics, specifically white new plastic pellets, represented the largest amount of MPs found, with densities decreasing in the order Cartagena > Coveñas > Puerto Colombia > Riohacha. This distribution was connected to the vicinity of MPs sources, marine currents and wind direction. The presence of secondary MPs was associated with urban centers and proximity to river mouths. The FTIR characterization showed polyethylene as the predominant resin type, with different degrees of surface oxidation. Aqueous extracts from sampled MPs were tested on Caenorhabditis elegans. Secondary MPs elicited greater toxicological responses than pellets, especially those from Cartagena Bay, suggesting MPs act as carriers for biologically-active pollutants.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Plásticos/análise , Poluentes Químicos da Água/análise , Animais , Animais Geneticamente Modificados , Praias , Caenorhabditis elegans/fisiologia , Região do Caribe , Colômbia , Ecotoxicologia/métodos , Monitoramento Ambiental , Microscopia Eletrônica de Varredura , Plásticos/química , Plásticos/toxicidade , Rios , Espectroscopia de Infravermelho com Transformada de Fourier , Urbanização , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Vento
17.
Mar Pollut Bull ; 146: 767-778, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426219

RESUMO

Various biogeochemical processes complicate carbon dioxide (CO2) behaviour in coastal oceans. Through eight summer surveys, detailed variations in CO2 mechanisms in the urbanized Jiaozhou Bay, China, were analysed. During the rainless period, respiration and dissolved inorganic carbon input from treated wastewater made the northeastern region a strong CO2 source, while the western region with cleaner seawater was a weak source because calcium carbonate (CaCO3) precipitation exceeded primary production. Rainfall events with different intensities and locations caused significantly different effects. When rainfall occurred over the sea, enhanced primary production caused a CO2 sink; when rainfall induced little terrestrial pollutant input, CaCO3 precipitation exceeded net primary production, leading to a CO2 source. When heavy rain caused bulk runoff, the northeastern region was a strong CO2 source because rivers flowing through downtown regions inputted considerable organic matter, while in the western region, runoff through suburbs and wetlands led to a strong sink.


Assuntos
Dióxido de Carbono/análise , Água do Mar/análise , Baías , Carbonato de Cálcio , Carbono/análise , Sequestro de Carbono , China , Clorofila , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Oceanos e Mares , Chuva , Rios , Salinidade , Estações do Ano , Temperatura Ambiente , Urbanização , Águas Residuárias/análise , Áreas Alagadas
18.
Environ Pollut ; 254(Pt B): 113073, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454573

RESUMO

Concentrations of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were examined in road dusts from some representative areas with different land-use types in northern Vietnam, providing updated information about the occurrence, sources, and risks of these pollutants in Southeast Asian region. The Vietnamese road dusts were contaminated with low to moderate levels of PAHs and Me-PAHs as compared to those from other countries in the world. Concentrations of PAHs and Me-PAHs (Σ34PAHs) decreased in the order: urban (median 1800; range 1100-5500) ≈ industrial (1300; 550-10,000) > suburban (450; 310-1300) ≈ rural road dust (330; 210-2300 ng g-1), suggesting an urban-rural declining trend and effects of urbanization-industrialization processes in PAH emission extent in Vietnam. The profiles and diagnostic ratios of PAHs and Me-PAHs in our samples revealed that these compounds were mainly derived from pyrogenic sources rather than petrogenic sources. Traffic emissions (e.g., vehicle exhaust, tire debris, and possible leaks of fuels, oils, and lubricants) were estimated as principal sources of PAHs and Me-PAHs, especially in the urban and industrial areas. Other pyrogenic sources (e.g., coal, wood, and biomass combustion) were also existed in the industrial, suburban, and rural areas, reflecting PAH origins from thermal industrial processes, open burning of agricultural by-products, and domestic energy utilization. Persons working outdoors and children in the urban and industrial areas were estimated to receive higher intake doses of PAHs and Me-PAHs, which were one to two orders of magnitude higher than those estimated for other groups. Except for potential cancer risk estimated for the occupational groups in the industrial area under the worst exposure scenarios, the non-cancer and cancer risk levels were generally acceptable; however, more comprehensive risk assessment considering other exposure pathways (e.g., inhalation and diet) is needed.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Agricultura , Biomassa , Criança , Carvão Mineral , Poeira/análise , Humanos , Medição de Risco , Urbanização , Emissões de Veículos , Vietnã , Madeira/química
19.
Sci Total Environ ; 687: 1232-1244, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412458

RESUMO

Increasing hotel/restaurant/café (HORECA) food consumption (HFC) has become one of the most prominent features of food consumption transformation under the background of rapid urbanization in China. Combining direct-weighing data (using 11,883 dishes in 164 restaurants) and literature data, this study, for the first time, quantitatively calculated the amount of HFC and its ecological footprint (EF) in China in 2002 and 2015 to depict the environmental effects of this transformation. The results indicated that per capita HFC tripled from 320 g/cap/meal in 2002 to 852 g/cap/meal in 2015, representing an average annual growth rate of 13%. In addition, by scaling up the HFC in 31 provinces/municipalities/autonomous regions to the national scale, HFC in China increased by 12,612 tons from 2002 to 2015. Finally, the total EF in the HORECA sector increased nearly 33 times (or 44,440 global ha), from 1348 global ha in 2002 to 45,788 global ha in 2015. The EF of Guangdong increased the most, surpassing 4000 global ha in 2015. These findings provide a scientific basis to support improved food resource spatial allocation and mitigation of regional resource pressure to achieve sustainable consumption under the current background of rapid urbanization in China.


Assuntos
Conservação dos Recursos Naturais , Indústria Alimentícia , Alimentos , China , Ecologia , Restaurantes , Análise Espaço-Temporal , Urbanização
20.
BMC Public Health ; 19(1): 1109, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412835

RESUMO

BACKGROUND: To estimate the relationship of the degree of urbanization to cardiovascular mortality and to risk behaviours before, during and after the 2008 economic crisis in Spain. METHODS: In three areas of residence - large urban areas, small urban areas and rural areas - we calculated the rate of premature mortality (0-74 years) from cardiovascular diseases before the crisis (2005-2007), during the crisis (2008-2010 and 2011-2013) and after the crisis (2014-2016), and the prevalence of risk behaviours in 2006, 2011 and 2016. In each period we estimated the mortality rate ratio (MRR) and the prevalence ratio, taking large urban areas as the reference. RESULTS: In men, no significant differences were observed in mortality between the two urban areas, while the MRR in rural areas went from 0.92 [95% confidence interval, 0.90-0.94) in 2005-2007 to 0.94 (0.92-0.96) in 2014-2016. In women, no significant differences were observed in mortality between the rural and large urban areas, whereas the MRR in small urban areas decreased from 1.11 (1.08-1.14) in 2005-2007 to 1.06 (1.02-1.09) in 2014-2016. The rural areas had the lowest prevalence of smoking, obesity and physical inactivity in men, and of obesity in women. No significant differences were observed in smoking or physical inactivity by area of residence in women. CONCLUSION: The pattern of cardiovascular mortality by degree of urbanization was similar before and after the crisis, although in women the excess mortality in small urban areas with respect to large urban areas was smaller after the crisis. The different pattern of risk behaviours in men and women, according to area of residence, could explain these findings.


Assuntos
Doenças Cardiovasculares/mortalidade , Recessão Econômica/estatística & dados numéricos , Assunção de Riscos , Urbanização , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mortalidade Prematura/tendências , Prevalência , Espanha/epidemiologia , Adulto Jovem
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