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1.
Sci Rep ; 12(1): 13244, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918427

RESUMO

Urban development continues to face the dilemma of spatial inequality of public facilities, particularly educational and medical facilities. Identifying inequalities in various types of public facilities and their driving mechanisms is crucial in reducing social inequality. However, information on this topic is limited. This study took 10 typical cities in China as cases. We used the methods of the Gini coefficient and hedonic price model as bases in evaluating the equality of nine types of education and medical facilities, focusing on the differences between urban and rural areas. Moreover, we further analyzed the driving factors of facility equality. Results showed that equality of public facilities in urban areas was significantly higher than that in rural areas. Primary schools, middle schools, and health service centers were relatively equal, and kindergartens and pharmacies were unequal only in rural areas. However, the equality of facilities with large-size or commercial attributes was not optimistic. Furthermore, there remained a significant gap among counties (or districts), which was mainly driven by population, economy, and building density in the form of logarithm and logarithmic linear models. Our research contributes to an in-depth understanding of the inequality of public facilities and further supports decision-making to improve social equality.


Assuntos
Serviços de Saúde , Logradouros Públicos , China , Cidades , Humanos , População Rural , Fatores Socioeconômicos , População Urbana
2.
PLoS One ; 16(11): e0259255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34784365

RESUMO

While shifts to high-intensity land cover have caused overwhelming biodiversity loss, it remains unclear how important natural land cover is to the occurrence, and thus the conservation, of different species groups. We used over 4 million plant species' observations to evaluate the conservation importance of natural land cover by its association with the occurrence probability of 1 122 native and 403 exotic plant species at 1 km resolution by species distribution models. We found that 74.9% of native species, 83.9% of the threatened species and 77.1% rare species preferred landscapes with over 50% natural land cover, while these landscapes only accounted for 15.6% of all grids. Most species preferred natural areas with a mixture of forest and open areas rather than areas with completely open or forested nature. Compared to native species, exotic species preferred areas with lower natural land cover and the cover of natural open area, but they both preferred extremely high and low cover of natural forest area. Threatened and rare species preferred higher natural land cover, either cover of natural forest area or cover of natural open area than not threatened and common species, but rare species were also more likely to occur in landscapes with 0-25% cover of natural open area. Although more natural land cover in a landscape will not automatically result in more native species, because there is often a non-linear increase in species occurrence probability when going from 0% to 100% natural land cover, for conserving purposes, over 80% natural land cover should be kept in landscapes for conserving threatened and very rare species, and 60% natural land cover is the best for conserving common native species. Our results stress the importance of natural areas for plant species' conservation. It also informs improvements to species conservation by increasing habitat diversity.


Assuntos
Conservação dos Recursos Naturais , Biodiversidade , Espécies em Perigo de Extinção , Florestas , Países Baixos , Desenvolvimento Vegetal/fisiologia , Plantas/classificação
3.
Bioessays ; 43(7): e2100041, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34085302

RESUMO

The structure and "metabolism" (movement and conversion of goods and energy) of urban areas has caused cities to be identified as "super-organisms", placed between ecosystems and the biosphere, in the hierarchy of living systems. Yet most such analogies are weak, and render the super-organism model ineffective for sustainable development of cities. Via a cluster analysis of 15 shared traits of the hierarchical living system, we found that industrialized cities are more similar to eukaryotic cells than to multicellular organisms; enclosed systems, such as factories and greenhouses, paralleling organelles in eukaryotic cells. We further developed a "super-cell" industrialized city model: a "eukarcity" with citynucleus (urban area) as a regulating centre, and organaras (enclosed systems, which provide the majority of goods and services) as the functional components, and cityplasm (natural ecosystems and farmlands) as the matrix. This model may improve the vitality and sustainability of cities through planning and management.


Assuntos
Ecossistema , Urbanização , Cidades
4.
Nat Commun ; 9(1): 4133, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297840

RESUMO

Rising demand for ruminant meat and dairy products in developing countries is expected to double anthropogenic greenhouse gas and ammonia emissions from livestock by 2050. Mitigation strategies are urgently needed to meet demand while minimizing environmental impacts. Here, we develop scenarios for mitigating emissions under local vs global supply policies using data from 308 livestock farms across mainland China, where emissions intensities are ~50% higher than those in developed nations. Intensification of domestic production and globalized expansion through increased trade result in reductions in global emissions by nearly 30% over a business-as-usual scenario, but at the expense of trading partners absorbing the associated negative externalities of environmental degradation. Only adoption of a mixed strategy combining global best-practice in sustainable intensification of domestic production, with increased green-source trading as a short-term coping strategy, can meet 2050 demand while minimizing the local and global environmental footprint of China's ruminant consumption boom.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/prevenção & controle , Efeito Estufa/prevenção & controle , Gado/crescimento & desenvolvimento , Ruminantes/crescimento & desenvolvimento , Gerenciamento de Resíduos/métodos , Algoritmos , Animais , Animais Domésticos/crescimento & desenvolvimento , Animais Domésticos/metabolismo , China , Internacionalidade , Gado/metabolismo , Modelos Teóricos , Ruminantes/metabolismo
5.
Sci Rep ; 7(1): 11226, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894226

RESUMO

Urban green spaces provide various ecosystem services, especially cultural services. Previous assessment methods depend either on hypothetic payments for ecosystems or real payments not directly related to ecosystems. In this paper, we established a method for assessing the cultural ecosystem services in any location in urban area using only two variables, green space (ecosystem) and land rent (real payment). We integrated the cultural and the regulating services into the total ecosystem services because urban green spaces provide almost no provisioning services. Results showed that the same area of green spaces near the center provided much higher cultural services than that near the urban edge; the regulating services accounted for 5% to 40% of the total ecosystem services from the center to the edge of urban area; along the center-edge gradient, there was a threshold out which the ecosystem services were lower than the maintenance cost of green spaces.

6.
Arch Virol ; 157(9): 1785-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22653537

RESUMO

This study reports the frequency and age distribution of porcine hokovirus (PHoV) in domestic pigs and characterizes the strains prevalent in eastern China. A total of 242 tissues from domestic pigs were tested for PHoV using PCR, and six near-full-length genome sequences were used for phylogenetic analysis. The PHoV sequences from domestic pigs in China showed a close relationship to sequences of isolates from Romania and Hong Kong. The results provide evidence that there are differences between PHoV in China compared to early isolates. PHoV infections are more frequent in 0- to 6-week-old pigs than in older ones.


Assuntos
Infecções por Parvoviridae/veterinária , Parvovirinae/isolamento & purificação , Sus scrofa/virologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Fatores Etários , Animais , China/epidemiologia , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Dados de Sequência Molecular , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Parvovirinae/genética , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Suínos
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