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1.
J Prev Med Public Health ; 53(2): 98-105, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32268464

RESUMEN

OBJECTIVES: Obesity is regarded as one of the most prominent health threats worldwide and a serious risk factor for non-communicable diseases, such as diabetes mellitus type 2, high blood pressure, cardiovascular diseases, and some types of cancer. Given the role that societal development-as reflected by the Human Development Index (HDI)-may play in the prevalence of obesity and overweight, this study aimed to investigate the degree to which the prevalence of obesity and overweight is affected by HDI and its components. METHODS: In this ecological study, the required data on HDI and its components were gathered from the latest report of the United Nations Development Program, and data on obesity and overweight were acquired from the latest reports published on the World Health Organization website. Statistical analyses were conducted using SPSS version 24.0. RESULTS: The prevalence of obesity was determined to be significantly higher among females than males, and the gross national index per capita was found to be significantly higher for males than females (p<0.05). Significant positive correlations were found between HDI and its components and sex, as well as indices of obesity and overweight. CONCLUSIONS: A significant positive correlation exists between HDI and obesity. As policy-makers attempt to improve the general welfare of the people, they should be aware of potential unwanted effects of development on the risk of obesity and overweight among the population.


Asunto(s)
Índice de Masa Corporal , Obesidad/epidemiología , Sobrepeso/epidemiología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Desarrollo Industrial , Entrevistas como Asunto , Masculino , Región Mediterránea/epidemiología , Persona de Mediana Edad , Obesidad/etiología , Prevalencia , Salud Pública , Factores de Riesgo , Distribución por Sexo , Factores Socioeconómicos , Urbanización , Organización Mundial de la Salud , Adulto Joven
2.
J Environ Manage ; 264: 110474, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250901

RESUMEN

This study examines the provincial impact of fiscal decentralization, in the form of shifting fiscal responsibilities of expenditures and revenues and others from the central government to lower local governments, as well as rapidly rising urbanization, on energy consumption for 31 Chinese provinces subject to relevant important control variables over the period 2006 to 2015. This analysis has implications for economic growth, efficiency and equality in China. To this end, the study employs multiple panel data analyses and panel quantile regressions to analyse this impact. Our findings show that fiscal decentralization has a non-linear relationship with energy consumption, which confirms the concave behaviour of fiscal decentralization in the Chinese provinces and underscores the validity of the environmental Kuznets curve hypothesis in those provinces, given the control variables. Moreover, increasing Chinese urbanization leads to high demand for energy consumption. Provincial governments can support eco-innovation and eco-investment by pursuing green growth strategies such as the expansion of the service sector and the boosting of the renewable energy sector: particularly when taking into account that coal, at one end of the spectrum, generates a 20 times greater carbon impact than renewables at the other.


Asunto(s)
Desarrollo Económico , Urbanización , Dióxido de Carbono , China , Política , Energía Renovable
3.
J Environ Manage ; 261: 110174, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148264

RESUMEN

Rapid industrialization and urbanization are often accompanied by deteriorating air quality that imposes substantial health and productivity costs on the local population. However, existing studies have generally found low marginal willingness to pay (WTP) for mitigating such damages. To understand the determinants and the extent of WTP for air quality improvements, we collected comprehensive socio-demographic and stated preference information from more than 3000 random respondents in three cities in China. Combining the survey data with air quality data from ground-level monitoring stations, we find that exposure to persistent air pollution is a significant determinant of the extent individuals are willing to pay for cleaner air. On average, urban residents are willing to pay 65 CNY (~10 USD) each year to improve air quality to World Health Organization standards. Males and individuals that are younger and more educated tend to have higher WTP. We also find that individuals with more knowledge of sustainability and who engage in more pro-environmental behaviors are willing to pay more. Compared to existing government monetary incentives to reduce air pollution, the public's total WTP for cleaner air is much higher. Overall, these results highlight the potential welfare gain for policymakers to implement more stringent air quality regulations to reduce pollution.


Asunto(s)
Contaminación del Aire , China , Ciudades , Contaminación Ambiental , Humanos , Masculino , Encuestas y Cuestionarios , Urbanización
4.
MMWR Morb Mortal Wkly Rep ; 69(11): 290-297, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32191688

RESUMEN

Of the 70,237 drug overdose deaths in the United States in 2017, approximately two thirds (47,600) involved an opioid (1). In recent years, increases in opioid-involved overdose deaths have been driven primarily by deaths involving synthetic opioids other than methadone (hereafter referred to as synthetic opioids) (1). CDC analyzed changes in age-adjusted death rates from 2017 to 2018 involving all opioids and opioid subcategories* by demographic characteristics, county urbanization levels, U.S. Census region, and state. During 2018, a total of 67,367 drug overdose deaths occurred in the United States, a 4.1% decline from 2017; 46,802 (69.5%) involved an opioid (2). From 2017 to 2018, deaths involving all opioids, prescription opioids, and heroin decreased 2%, 13.5%, and 4.1%, respectively. However, deaths involving synthetic opioids increased 10%, likely driven by illicitly manufactured fentanyl (IMF), including fentanyl analogs (1,3). Efforts related to all opioids, particularly deaths involving synthetic opioids, should be strengthened to sustain and accelerate declines in opioid-involved deaths. Comprehensive surveillance and prevention measures are critical to reducing opioid-involved deaths, including continued surveillance of evolving drug use and overdose, polysubstance use, and the changing illicit drug market; naloxone distribution and outreach to groups at risk for IMF exposure; linkage to evidence-based treatment for persons with substance use disorders; and continued partnerships with public safety.


Asunto(s)
Analgésicos Opioides/envenenamiento , Sobredosis de Droga/mortalidad , Adolescente , Adulto , Distribución por Edad , Anciano , Niño , Preescolar , Grupos de Población Continentales/estadística & datos numéricos , Sobredosis de Droga/etnología , Grupos Étnicos/estadística & datos numéricos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Distribución por Sexo , Estados Unidos/epidemiología , Urbanización , Adulto Joven
5.
J Environ Manage ; 264: 110381, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32217308

RESUMEN

China has implemented main functional areas planning (MFAP) since 2010, which is essential for improving the efficiency of land space utilization and achieving sustainable urban development. Quantitative assessments of the urban development levels (UDLs) at the county level across China after the implementation of MFAP have not been well-documented. In this study, a unified indicator system was developed, and the UDLs of 2850 counties in China after MFAP implementation were evaluated. The results showed that MFAP played a positive role in urban development in China. The UDLs in China generally increased but showed obvious spatial differences. The higher UDLs were mostly found in the counties in the five urban belts, which reflects the overall urban layout of China. The UDLs were generally low in the western counties in comparison with those in the eastern part of China. The differences in the UDLs from east to west were greater than those from north to south. Moreover, the differences in the UDLs presented a spatial agglomeration effect. This study could offer insight into the refinement of MFAP in China and sustainable urban development in developing countries.


Asunto(s)
Países en Desarrollo , Urbanización , China , Demografía , Geografía , Humanos , Población Urbana
6.
Sci Total Environ ; 714: 135793, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-32018940

RESUMEN

Recent studies suggest that oncogenic processes (from precancerous lesions to metastatic cancers) are widespread in wild animal species, but their importance for ecosystem functioning is still underestimated by evolutionary biologists and animal ecologists. Similar to what has been observed in humans, environmental modifications that often place wild organisms into an evolutionary trap and/or exposes them to a cocktail of mutagenic and carcinogenic pollutants might favor cancer emergence and progression, if animals do not up-regulate their defenses against these pathologies. Here, we compared, for the first time, the expression of 59 tumor-suppressor genes in blood and liver tissues of urban and rural great tits (Parus major); urban conditions being known to favor cancer progression due to, among other things, exposure to chemical or light pollution. Contrary to earlier indications, once we aligned the transcriptome to the great tit genome, we found negligible differences in the expression of anti-cancer defenses between urban and rural birds in blood and liver. Our results indicate the higher expression of a single caretaker gene (i.e. BRCA1) in livers of rural compared to urban birds. We conclude that, while urban birds might be exposed to an environment favoring the development of oncogenic processes, they seem to not upregulate their cancer defenses accordingly and future studies should confirm this result by assessing more markers of cancer defenses. This may result in a mismatch that might predispose urban birds to higher cancer risk and future studies in urban ecology should take into account this, so far completely ignored, hazard.


Asunto(s)
Neoplasias , Passeriformes , Animales , Ecosistema , Contaminación Ambiental , Neoplasias/veterinaria , Urbanización
7.
J Environ Manage ; 260: 110143, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090836

RESUMEN

This paper examines the short-run and long-run effects of economic, sociological and energy factors on environmental degradation in 28 European countries. In so doing, we employ Panel Vector Autoregressive (PVAR) and Fully Modified OLS (FMOLS) approaches on data from 1990 to 2014 in a STIRPAT (Stochastic Impacts by Regression on Population, Affluence, and Technology) framework. Key empirical results indicate that these factors may contribute to environmental improvement in the short run; however, there are adverse implications in the long-run. Specifically, economic factors including economic growth, trade openness and foreign direct investment cause environmental degradation in the under-analysis economies. The sociological factors as measured by the population growth and the level of urbanization also show a negative impact on the environmental degradation in the short-run but in the long run, both population size and urbanization increase environmental degradation. These findings are in line with the concerns raised by Thomas Robert Malthus in his Essay on the Principle of Population. With regards to the energy factors, it indicates that the renewable energies help the European environment by reducing the level of carbon dioxide emissions whereas the higher energy intensity is an ecological threat. Our results remain robust in the EKC framework.


Asunto(s)
Desarrollo Económico , Energía Renovable , Dióxido de Carbono , Europa (Continente) , Inversiones en Salud , Urbanización
8.
J Environ Manage ; 260: 110168, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090851

RESUMEN

Sandy beaches are not roads, but they have been used as such worldwide, threatening endemic fauna such as ghost crabs (Crustacea: Ocypodidae). The objective of the present study was to identify the spatial factors influencing the incidence of ghost crabs (Ocypode quadrata) killed by vehicles. This study included a systematic study of carcasses with clear signals of crushing by cars on beaches with distinct urbanization levels and on dirt roads crossing low-urbanized beach stretches. Predictive variables (e.g., tyre tracks on the sand, proxies of urbanization, distance from coastal lagoons and beach width) were obtained for the kill points and random points. Generalized linear models with binomial distributions showed that the number of tyre tracks nearby (positive correlation) and indicators of urbanization in the environment (negative correlation) were the main variables explaining ghost crab kills on the beach. Similarly, the likelihood of finding crabs killed by vehicles on the dirt road was associated with the areas with the densest ghost crab populations (higher beach width and low-urbanized areas). Therefore, as an important conservation strategy and mitigation action, vehicle traffic must be severely controlled mainly on low-urbanized beaches, both on the sand and dirt roads crossing natural beach vegetation.


Asunto(s)
Playas , Braquiuros , Animales , Ecología , Alimentos Marinos , Urbanización
9.
BMC Health Serv Res ; 20(1): 90, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-32024537

RESUMEN

BACKGROUND: Vietnam has been successful in increasing access to maternal, neonatal, and child health (MNCH) services during last decades; however, little is known about whether the primary MNCH service utilization has been properly utilized under the recent rapid urbanization. We aimed to examine current MNCH service utilization patterns at a district level. METHODS: The study was conducted qualitatively in a rural district named Quoc Oai. Women who gave a birth within a year and medical staff at various levels participated through 43 individual in-depth interviews and 3 focus group interviews. RESULTS: Primary MNCH services were underutilized due to a failure to meet increased quality needs. Most of the mothers preferred private clinics for antenatal care and the district hospital for delivery due to the better service quality of these facilities compared to that of the commune health stations (CHSs). Mothers had few sociocultural barriers to acquiring service information or utilizing services based on their improved standard of living. A financial burden for some services, including caesarian section, still existed for uninsured mothers, while their insured counterparts had relatively few difficulties. CONCLUSIONS: For the improved macro-efficiency of MNCH systems, the government needs to rearrange human resources and/or merge some CHSs to achieve economies of scale and align with service volume distribution across the different levels.


Asunto(s)
Utilización de Instalaciones y Servicios/estadística & datos numéricos , Servicios de Salud Materno-Infantil , Población Suburbana , Urbanización , Niño , Femenino , Grupos Focales , Accesibilidad a los Servicios de Salud , Humanos , Recién Nacido , Embarazo , Atención Primaria de Salud , Investigación Cualitativa , Vietnam
10.
Ecotoxicol Environ Saf ; 192: 110271, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32044605

RESUMEN

Pollution with total petroleum hydrocarbons (TPHs) is a global concern and particularly in coastal environments. Polycyclic aromatic hydrocarbons (PAHs) are regarded as the most toxic components of TPHs and they can also be derived from other sources. Fangcheng Port is considered as a representative emerging coastal city in China, but the status, sources, and hazards to organisms and humans with respect to contamination with PAHs and TPHs are unknown in the coastal regions of this area. Therefore, in this study, we cloned cytochrome P450 family genes (CYP1A1, CYP3A, and CYP4) and heat shock protein 70 gene (HSP70) in the clam Meretrix meretrix as well as optimizing the method for measuring the 7-ethoxyresorufin O-deethylase activity. These molecular indicators and four specific physiological indexes were found to be appropriate biomarkers for indicating the harmful effects of PAHs and TPHs on clams after exposure to the crude oil water-soluble fraction. In field monitoring surveys, we found that the 2- and 3-ring PAHs were dominant in the clams whereas the 4- to 6-ring PAHs were dominant in the sediments at each site. The PAH levels (3.63-12.77 ng/g wet weight) in wild clams were lower, whereas the TPH levels (13.25-70.50 µg/g wet weight) were higher compared with those determined previous in China and elsewhere. The concentrations of PAHs and TPHs in the sediments (19.20-4215.76 ng/g and 3.65-866.40 µg/g dry weight) were moderate compared with those in other global regions. Diagnostic ratio analysis demonstrated that the PAHs were derived mainly from pyrogenic sources. The TPHs may have come primarily from industrial effluents, land and maritime transportation, or fishing activities. The Integrated Biomarker Response version 2 indexes indicated that the clams collected from site S5 exhibited the most harmful effects due to contamination by PAHs and TPHs. Human health risk assessments demonstrated that the risks due to PAHs and TPHs following the consumption of clams can be considered acceptable. Our results suggest that continuous monitoring of contamination by PAHs and TPHs is recommended in this emerging coastal city as well as assessing their human health risks.


Asunto(s)
Monitoreo Biológico/métodos , Bivalvos/efectos de los fármacos , Biomarcadores Ambientales/efectos de los fármacos , Sedimentos Geológicos/química , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Bivalvos/metabolismo , China , Ciudades , Humanos , Hidrocarburos Policíclicos Aromáticos/metabolismo , Urbanización , Contaminantes Químicos del Agua/metabolismo
11.
Chemosphere ; 248: 126015, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32032874

RESUMEN

Sixteen polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Dianchi Lake, southwest China, were analysed. The influence of changes in China's energy structure for 2-6 ringed PAHs was investigated to assess sources and the impact of socioeconomic development on temporal changes in concentrations. The concentration of the ΣPAH16 ranged from 746 to 2293 ng g-1. Prior to the 1960s relatively low concentrations of the ΣPAH16 and a larger proportion of 2-3-ring PAHs indicated that biomass combustion was the main source of PAHs. A rapid increase in the concentrations of 2-3 ring PAHs between 1975 and 2004 was attributed to population growth and coal consumption. A declining trend since 2004 was interpreted as being due to local changes in household energy usage. Increased concentrations of 4-ring PAH between 1975-2005 and 5-6-ring PAHs between the 1980s to 2004 showed correlations with increased coal consumption and the number of motor vehicles, respectively. These were caused by rapid urbanization and industrialization in the Dianchi watershed following the implementation of the Reform and Open Policy in 1978. A subsequent decline in the concentrations of 4-ring and 5-6-ring PAHs may have been due to decreased coal consumption and improvements in emission standards, respectively. Source apportionment by a PMF model revealed that coal combustion (29.2%), vehicle emissions (24.2%), petrogenic sources (21.8%), and biomass combustion (24.9%) were the sources of PAHs in the lake sediment core, and that coal combustion was the most important regional source of PAHs pollution.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Biomasa , China , Carbón Mineral/análisis , Desarrollo Económico , Contaminación Ambiental/análisis , Sedimentos Geológicos/química , Desarrollo Industrial , Lagos/química , Urbanización , Emisiones de Vehículos/análisis
12.
Chemosphere ; 247: 125991, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32069737

RESUMEN

Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexabromobiphenyl (BB-153), novel brominated flame retardants (NBFRs), and unsubstituted/methylated polycyclic aromatic hydrocarbons (PAHs/Me-PAHs) were simultaneously monitored in the air samples collected from Vietnamese urban and vehicular waste processing areas by using polyurethane foam-based passive air sampling (PUF-PAS) method. Concentrations (pg m-3) of organic pollutants decreased in the order: PAHs (median 29,000; range 5100-100,000) > Me-PAHs (6000; 1000-33,000) > PCBs (480; 170-1100) > PBDEs (11; 5.3-86) > NBFRs (0.20; n. d. - 51) > BB-153 (n.d.). The difference in total PCB and PBDE concentrations between the urban and waste processing air samples was not statistically significant. Meanwhile, levels of PAHs, Me-PAHs, benzo [a]pyrene equivalents (BaP-EQs), and toxic equivalents of dioxin-like PCBs (WHO-TEQs) were much higher in the waste processing sites. This is the first report on the abundance of mono- and di-CBs (notably CB-11) in the air from a developing country, suggesting their roles as emerging and ubiquitous air pollutants. Our results have indicated potential sources of specific organic pollutants such as dioxin-like PCBs, PAHs, and Me-PAHs from improper treatment of end-of-life vehicles and other vehicle related materials (e.g., waste oils and rubber tires), as well as current emission of PCBs and PBDEs in the urban area in Vietnam. Further atmospheric monitoring studies should be conducted in this developing country that cover both legacy and emerging contaminants with a focus on areas affected by rapid urbanization and informal waste processing activities.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Poliuretanos , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Urbanización , Vietnam , Administración de Residuos
13.
PLoS One ; 15(2): e0228090, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32023270

RESUMEN

Globally, cities are growing rapidly in size and density and this has caused profound impacts on urban forest ecosystems. Urbanization requiring deforestation reduces ecosystem services that benefit both city dwellers and biodiversity. Understanding spatial and temporal patterns of vegetation changes associated with urbanization is thus a vital component of future sustainable urban development. We used Landsat time series data for three decades from 1988 to 2018 to characterize changes in vegetation cover and habitat connectivity in the Perth Metropolitan Area, in a rapidly urbanising Australian biodiversity hotspot, as a case study to understand the impacts of urbanization on urban forests. Moreover, as golf courses are a major component in urban areas, we assessed the role of golf courses in maintaining vegetation cover and creating habitat connectivity. To do this we employed (1) land use classification with post-classification change detection, and (2) Morphological Spatial Pattern Analysis (MSPA). Over 17,000 ha of vegetation were cleared and the area of vegetation contributing to biodiversity connectivity was reduced significantly over the three decades. The spatial patterns of vegetation loss and gain were different in each of the three decades (1988-2018) reflecting the implementation of urban planning. Furthermore, MSPA analysis showed that the reduction in vegetation cover led to habitat fragmentation with a significant decrease in the core and bridge classes and an increase in isolated patches in the urban landscape. Golf courses played a useful role in maintaining vegetation cover and contributing to connectivity in a regional biodiversity hotspot. Our findings suggest that for future urban expansion, urban planning needs to more carefully consider the impacts of deforestation on connectivity in the landscape. Moreover, there is a need to take into consideration opportunities for off-reserve conservation in smaller habitat fragments such as in golf courses in sustainable urban management.


Asunto(s)
Conservación de los Recursos Naturales/tendencias , Urbanización , Ecosistema , Golf , Análisis Espacial
14.
PLoS One ; 15(1): e0220936, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32004319

RESUMEN

Coastal areas are urbanizing at unprecedented rates, particularly in low- and middle-income countries. Combinations of long-standing and emerging problems in these urban areas generate vulnerability for human well-being and ecosystems alike. This baseline study provides a spatially explicit global systematization of these problems into typical urban vulnerability profiles for the year 2000 using largely sub-national data. Using 11 indicator datasets for urban expansion, urban population growth, marginalization of poor populations, government effectiveness, exposures and damages to climate-related extreme events, low-lying settlement, and wetlands prevalence, a cluster analysis reveals a global typology of seven clearly distinguishable clusters, or urban profiles of vulnerability. Each profile is characterized by a specific data-value combination of indicators representing mechanisms that generate vulnerability. Using 21 studies for testing the plausibility, we identify seven key profile-based vulnerabilities for urban populations, which are relevant in the context of global urbanization, expansion, and climate change. We show which urban coasts are similar in this regard. Sensitivity and exposure to extreme climate-related events, and government effectiveness, are the most important factors for the huge asymmetries of vulnerability between profiles. Against the background of underlying global trends we propose entry points for profile-based vulnerability reduction. The study provides a baseline for further pattern analysis in the rapidly urbanizing coastal fringe as data availability increases. We propose to explore socio-ecologically similar coastal urban areas as a basis for sharing experience and vulnerability-reducing measures among them.


Asunto(s)
Cambio Climático , Ecosistema , Urbanización/tendencias , Inundaciones , Humanos , Crecimiento Demográfico , Población Urbana/tendencias , Humedales
15.
Oecologia ; 192(4): 1073-1083, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32062703

RESUMEN

Urbanization alters the landscape, degrades and fragments habitats, and can have a profound effect on species interactions. Plant-pollinator networks may be particularly sensitive to urbanization, because plants and their insect pollinators have been shown to respond to urbanization both positively and negatively. To better understand the relationship between urbanization, pollinator behavior, and season on pollinator-mediated plant reproduction, we created 30 experimental plant populations along an urbanization gradient in the Greater Toronto Area, Canada. To test how urbanization affects plant reproduction and between-patch pollen dispersal, we created a standard hermaphroditic plant patch at each site, and a male-sterile plant patch at a subset of sites. We measured plant reproduction in the early and late summer in each of 2 years. Plants in urban sites produced significantly fewer flowers than plants in the nonurban sites, whereas seed number per plant either increased or decreased with urbanization, depending on the season. Experimental populations in urban sites also exhibited reduced pollen dispersal between patches. Pollen dispersal between patches was greatest early in the summer and declined with increased impervious surface and proximity to the city. Together, our results are likely caused by variation in environmental conditions and pollinator services across the urban gradient, resulting in pollen limitation and pollen dispersal differences among sites. Our work adds to the small but growing body of literature on urban plant-pollinator interactions and suggests that responses to urbanization are context-dependent.


Asunto(s)
Polinización , Urbanización , Animales , Canadá , Ciudades , Flores , Reproducción
16.
PLoS One ; 15(2): e0228881, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32023321

RESUMEN

Urban environments are unique because fragments of natural or semi-natural habitat are embedded within a potentially permeable matrix of human-dominated areas, creating increased landscape and, potentially, habitat heterogeneity. In addition, urban areas can provide diet subsidies for wildlife species in the form of fruiting ornamental plants, trash, and domestic animals. Ecological opportunity in the forms of habitat and food heterogeneity are thought to be important mechanisms in maintaining individual specialization. Identifying which contexts, traits, and mechanisms determine the success or failure of individuals within an urban wildlife population could potentially provide predictions about which populations may succeed in human-dominated landscapes and which may experience local extinction. We used both scat and stable isotope analysis of whiskers to investigate the degree to which coyotes (Canis latrans) utilized anthropogenic subsidies and exhibited individual diet specialization across the urban-rural gradient in southern California. Land use surrounding scat and isotope sample locations was also evaluated to determine the effect of land cover on diet. Human food constituted a significant portion of urban coyote diet (22% of scats, 38% of diet estimated by stable isotope analysis). Domestic cats (Felis catus) and ornamental fruit and seeds were also important items in urban coyote diets. Consumption of anthropogenic items decreased with decreasing urbanization. In suburban areas, seasonality influenced the frequency of occurrence of anthropogenic subsidies with increased consumption in the dry season. The amount of altered open space (areas such as golf courses, cemeteries, and landscaped parks) nearby had a negative effect on the consumption of anthropogenic items in both urban and suburban areas. Contrary to our hypothesis, urban coyotes displayed reduced between-individual variation compared to suburban and rural coyotes. It is possible that the core urban areas of cities are so densely developed and subsidized that wildlife inhabiting these areas actually have reduced ecological opportunity. Suburban animals had the broadest isotopic niches and maintained similar individual specialization to rural coyotes. Wildlife in suburban areas still have access to relatively undisturbed natural areas while being able to take advantage of anthropogenic subsidies in neighboring residential areas. Therefore, areas with intermediate urban development may be associated with increased ecological opportunity and specialization.


Asunto(s)
Coyotes/fisiología , Animales , Animales Salvajes , California , Isótopos de Carbono/análisis , Ciudades , Dieta , Ecosistema , Heces/química , Femenino , Humanos , Masculino , Modelos Biológicos , Recursos Naturales , Isótopos de Nitrógeno/análisis , Estaciones del Año , Urbanización , Vibrisas/química
17.
PLoS One ; 15(2): e0226046, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32045414

RESUMEN

There is an increasingly growth of China's social security expenditure(SSE) during the past decade. Regarding to the great responsibility and impact on citizens' welfare and economic development, the efficiency of social security expenditure has inevitably become the focus of growing attention. Based on Chinese provincial panel data over the period 2007-2016, a three-stage DEA model was conducted and found that the efficiency level of 29 provinces/municipalities did not reach the efficiency frontier. Environmental factors and statistical noises have a significant impact on the efficiency of SSE, if environmental factors and statistical noises are not considered, the efficiency of SSE in China is likely to be underestimated. The regional differences in the efficiency of SSE were significant and ranked by descending order as follows: central region, eastern region and western region.


Asunto(s)
Eficiencia Organizacional , Modelos Teóricos , Seguridad Social/economía , Presupuestos , China , Ciudades , Desarrollo Económico , Ambiente , Humanos , Mercadeo Social , Bienestar Social , Urbanización
18.
PLoS One ; 15(2): e0228683, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32040490

RESUMEN

Human activities have greatly influenced the natural nitrogen cycle, causing dramatic degradation of ecosystem function. Net anthropogenic nitrogen input (NANI) is an important factor contributing to the impact of human activities on the regional nitrogen cycle. Here, we analyzed the temporal and spatial variation of NANI in the Pearl River Basin of China between 1986 to 2015, and found that the total amount of NANI significantly increased from 3,362.25 kg N km-2 yr-1 to 8,071.15 kg N km-2 yr-1. Application of nitrogen fertilizers was the largest component of NANI in the Basin, accounting for 55.53% in the total NANI, followed by food/feed net nitrogen input (21.26%), atmospheric nitrogen deposition (12.95%), and crop nitrogen fixation (10.26%). Over the last three decades, nitrogen inputs from atmospheric nitrogen deposition have become the second largest source of NANI due to rapid industrialization and urbanization in the region. Regression analysis showed that the rapid growth of both GDP and population density were the main contributors to the increase of NANI. In addition, the increase in the number of red tides in the Pearl River Estuary was strongly correlated with NANI discharge (R2 = 0.90, p<0.01), suggesting the NANI's eutrophication effect. In total, this study provides a quantitative understanding of the temporal and spatial variations of NANI in the Pearl River Basin as well as the effects of NANI on estuarine waters, and offered key information for developing an integrated strategy for watershed nitrogen management.


Asunto(s)
Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Fertilizantes , Nitrógeno/análisis , Ríos , China , Ecosistema , Estuarios , Eutrofización , Geografía , Análisis de Regresión , Análisis Espacio-Temporal , Urbanización
19.
PLoS One ; 15(2): e0228537, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049986

RESUMEN

Urbanization modifies land surface characteristics with consequent impacts on local energy, water, and carbon dioxide (CO2) fluxes. Despite the disproportionate impact of cities on CO2 emissions, few studies have directly quantified CO2 conditions for different urban land cover patches, in particular for arid and semiarid regions. Here, we present a comparison of eddy covariance measurements of CO2 fluxes (FC) and CO2 concentrations ([CO2]) in four distinct urban patches in Phoenix, Arizona: a xeric landscaping, a parking lot, a mesic landscaping, and a suburban neighborhood. Analyses of diurnal, daily, and seasonal variations of FC and [CO2] were related to vegetation activity, vehicular traffic counts, and precipitation events to quantify differences among sites in relation to their urban land cover characteristics. We found that the mesic landscaping with irrigated turf grass was primarily controlled by plant photosynthetic activity, while the parking lot in close proximity to roads mainly exhibited the signature of vehicular emissions. The other two sites that had mixtures of irrigated vegetation and urban surfaces displayed an intermediate behavior in terms of CO2 fluxes. Precipitation events only impacted FC in urban patches without outdoor water use, indicating that urban irrigation decouples CO2 fluxes from the effects of infrequent storms in an arid climate. These findings suggest that the proportion of irrigated vegetation and urban surfaces fractions within urban patches could be used to scale up CO2 fluxes to a broader city footprint.


Asunto(s)
Ciclo del Carbono/fisiología , Dióxido de Carbono/química , Poaceae/fisiología , Lluvia , Suelo , Urbanización , Arizona , Dióxido de Carbono/análisis , Ciudades , Clima Desértico , Humanos , Estaciones del Año , Suelo/química , Factores de Tiempo , Emisiones de Vehículos/análisis , Ciclo Hidrológico/fisiología
20.
Int J Biometeorol ; 64(4): 571-584, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31907654

RESUMEN

Impacts of climate change (e.g., abnormal growth in plants, early flowering, and shifting vegetation zones) are being detected throughout the world. Urban land use and its resulting microclimates work in conjunction with the impacts of climate change. Among the principal environmental signals that modulate bud flush, only temperature has changed significantly in recent years. Throughout South Korea, abnormal shoots (usually known as lammas shoots) in Korean red pine (Pinus densiflora), which were once a rare phenomenon, have become notably more common in recent years. The phenomenon is prominent in urban site of each local area. These abnormal shoots appear at a higher frequency and grow to longer lengths in Seoul's hotter urban center than in suburban sites and showed a close positive correlation with urban density and a close negative correlation with vegetation cover expressed as NDVI. Differences in temperature among the urban center, urban edge, and suburban greenbelt were significantly correlated with land-use intensity. Korean red pines planted in urban parks at sites in urban centers showed a lower frequency of abnormal shoots, and the length of the shoots was shorter, compared with those at the other urban sites. Furthermore, the phenology of Korean red pines in an urban park with a fountain showed a spatial difference, depending upon the distance from the fountain: pine trees close to the fountain did not produce abnormal shoots, but abnormal shoot growth increased with the distance from the fountain. These results are noteworthy because they are related to the cooling effects of evapotranspiration from vegetated landscapes and evaporation from a water body. From the results of this study, we could confirm that microclimate change due to urbanization accelerates the impacts of climate change on plant phenology. Furthermore, we identified the possibility that judicious land-use planning could contribute to minimizing the adverse effects of climate change.


Asunto(s)
Pinus , Urbanización , Microclima , República de Corea , Seúl
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