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1.
Sci Total Environ ; 785: 147189, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933764

RESUMO

Fire and herbivory are important natural disturbances in grassy biomes. Both drivers are likely to influence belowground microbial communities but no studies have unravelled the long-term impact of both fire and herbivory on bacterial and fungal communities. We hypothesized that soil bacterial communities change through disturbance-induced shifts in soil properties (e.g. pH, nutrients) while soil fungal communities change through vegetation modification (biomass and species composition). To test these ideas, we characterised soil physico-chemical properties (pH, acidity, C, N, P and exchangeable cations content, texture, bulk density, moisture), plant species richness and biomass, microbial biomass and bacterial and fungal community composition and diversity (using 16S and ITS rRNA amplicon sequencing, respectively) in six long-term (18 to 70 years) ecological research sites in South African savanna and grassland ecosystems. We found that fire and herbivory regimes profoundly modified soil physico-chemical properties, plant species richness and standing biomass. In all sites, an increase in woody biomass (ranging from 12 to 50%) was observed when natural disturbances were excluded. The intensity and direction of changes in soil properties were highly dependent on the topo-pedo-climatic context. Overall, fire and herbivory shaped bacterial and fungal communities through distinct driving forces: edaphic properties (including Mg, pH, Ca) for bacteria, and vegetation (herbaceous biomass and woody cover) for fungi. Fire and herbivory explained on average 7.5 and 9.8% of the fungal community variability, respectively, compared to 6.0 and 5.6% for bacteria. The relatively small changes in microbial communities due to natural disturbance is in stark contrast to dramatic vegetation and edaphic changes and suggests that soil microbial communities, having evolved with disturbance, are resistant to change. This represents both a buffer to short-term anthropogenic-induced changes and a restoration challenge in the face of long-term changes.


Assuntos
Incêndios , Herbivoria , Bactérias , Biomassa , Ecossistema , Fungos , Pradaria , Solo , Microbiologia do Solo
2.
Int J Equity Health ; 19(1): 223, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334349

RESUMO

We examined urban-rural differences in educational inequalities in mortality in the Baltic countries (Estonia, Latvia, Lithuania) and Finland in the context of macroeconomic changes. Educational inequalities among 30-74 year olds were examined in 2000-2003, 2004-2007, 2008-2011 and 2012-2015 using census-linked longitudinal mortality data. We estimated age-standardized mortality rates and the relative and slope index of inequality. Overall mortality rates were larger in rural areas except among Finnish women. Relative educational inequalities in mortality were often larger in urban areas among men but in rural areas among women. Absolute inequalities were mostly larger in rural areas excepting Finnish men. Between 2000-2003 and 2012-2015 relative inequalities increased in most countries while absolute inequalities decreased except in Lithuania. In the Baltic countries the changes in both relative and absolute inequalities tended to be more favorable in urban areas; in Finland they were more favorable in rural areas. The overall pattern changed during the reccessionary period from 2004-2007 to 2008-2011 when relative inequalities often diminished or the increase slowed, while the decrease in absolute inequalities accelerated with larger improvements observed in urban areas. Despite substantial progress in reducing overall mortality rates in both urban and rural areas in all countries, low educated men and women in rural areas in the Baltic countries are becoming increasingly disadvantaged in terms of mortality reduction.


Assuntos
Escolaridade , Disparidades nos Níveis de Saúde , Mortalidade/tendências , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Idoso , Países Bálticos/epidemiologia , Feminino , Finlândia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores Socioeconômicos
3.
Scand J Soc Med ; 21(3): 150-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8235500

RESUMO

The purpose of the present study was to examine the general morbidity and mortality rates in the three Baltic republics--Estonia, Latvia and Lithuania during a decade before the collapse of the Soviet Union. Official statistical data were used to compare morbidity and mortality rates. A method of standardization and life table functions were employed. Soviet morbidity statistics were predominantly descriptive, and based mainly on crude rates registered cases of illness during a year per 100,000 population. The death rates during the Soviet period are a better indicator of the health of the populations than more specific health indicators. A general deterioration of the ecological, social and economic situation in the Baltic republics at the end of the 1980s and early 1990s may have resulted in the mortality rising and aborted any trends to increasing life expectancy in the next few years thus requiring more radical reforms in health and social policy. The study demonstrates a noticeable difference in mortality rates between demographic and socio-economic groups in the Baltic states.


Assuntos
Causas de Morte , Morbidade , Mortalidade , Absenteísmo , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comparação Transcultural , Estônia/epidemiologia , Feminino , Humanos , Lactente , Letônia/epidemiologia , Expectativa de Vida/tendências , Tábuas de Vida , Lituânia/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros/estatística & dados numéricos , Reprodutibilidade dos Testes , Fatores Sexuais , Fatores Socioeconômicos
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