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1.
Sci Total Environ ; 521-522: 346-58, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25863313

RESUMO

The impacts of climate change on Po River discharges are investigated through a set of climate, hydrological, water-balance simulations continuous in space and time. Precipitation and 2m mean temperature fields from climate projections under two different representative concentration pathways, RCP4.5 and RCP8.5, have been used to drive the hydrological model. Climate projections are obtained nesting the regional climate model COSMO-CLM into the global climate model CMCC-CM. The bias in climate projections is corrected applying the distribution derived quantile mapping. The persistence of climate signal in precipitation and temperature after the bias correction is assessed in terms of climate anomaly for 2041-2070 and 2071-2100 periods versus 1982-2011. To account for the overall uncertainty of emission scenarios, climate models and bias correction, the hydrological/water balance simulations are carried out using both raw and bias corrected climate datasets. Results show that under both RCPs, either considering raw and bias corrected climate datasets, temperature is expected to increase on the whole Po River basin and in all the seasons; the most significant changes in precipitation and discharges occur in summer, when the reduction of precipitation leads to an increase in low flow duration and occurrence likelihood, and in autumn and winter where precipitation shows a positive variation increasing the high flows frequency.

2.
J Theor Biol ; 289: 74-82, 2011 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-21875600

RESUMO

The tree-grass co-existence in savannas involves multiple and sometimes connected biogeophysical conditions. The savanna domain, its boundaries, and transitions (gradual or abrupt) to other vegetation types (i.e., grassland or forest) are fundamental for the management of ecosystems and for preserving the biodiversity in present conditions and in future changing scenarios. Here we investigate the savanna domain within grazers-fire and browsers-fire parameter planes through a simple ecohydrological model of tree-grass-soil water dynamics. Stability maps allow to identify savanna domains and to show the behavior of vegetation under increasing pressure of grazing and browsing. Stability maps shed light on the causes behind possible vegetation abrupt transitions (e.g., forest collapse and bush encroachment). An application to 15 African savannas sites is presented and discussed with the support of a local sensitivity analysis of the model's parameters.


Assuntos
Incêndios , Herbivoria/fisiologia , Modelos Biológicos , Poaceae/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , África , Animais , Ecossistema , Solo , Água
3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(5 Pt 1): 051908, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18643103

RESUMO

In drylands the soil water availability is a key factor ruling the architecture of the ecosystem. The soil water reflects the exchanges of water among soil, vegetation, and atmosphere. Here, a dryland ecosystem is investigated through the analysis of the local interactions between soil water and vegetation forced by rainfall having seasonal and stochastic occurrence. The evolution of dryland ecosystems is represented by a system of two differential equations, having two steady states, one vegetated and the other unvegetated. The rainfall forcing is described by a diffusion process with monthly parameters. In each of the two possible steady states, the probability density functions of soil water and vegetation are derived analytically in terms of the rainfall distribution. The results show how the seasonality of rainfall influences the oscillation of the ecosystem between its vegetated steady state during the wet season and its unvegetated steady state during the dry season.


Assuntos
Ecossistema , Modelos Biológicos , Desenvolvimento Vegetal , Plantas/metabolismo , Chuva/química , Estações do Ano , Solo/análise , Água/metabolismo , Simulação por Computador , Modelos Estatísticos , Processos Estocásticos
4.
Eur Psychiatry ; 16(8): 451-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11777735

RESUMO

The stigmatisation of the psychiatric patient is still a strong barrier to the integration process of these subjects in our society. Therefore, it is necessary to identify what types of prejudices exist and the types of variables with which they are linked, in order to plan strategies to reduce them. In this exploratory study we administered a semi-structured interview to 303 subjects in order to examine the relationships between social attitudes towards mental disorders and some social demographic variables, the information about mental disorders and the previous 'contacts' with psychiatric patients. The data analysis shows that there is a relationship between knowledge of psychiatric patients and a more positive attitude towards them (i.e., less fear, more integration and work opportunities). This study is to be considered preliminary as far as people's attitudes towards psychiatric patients are concerned. This result encourages the planning and implementation of sensitisation and information programs concerning mental disorders, in the sense that increasing the knowledge of mental disorders could lead to significant achievements in the important fight against the stigma surrounding psychiatric patients.


Assuntos
Atitude Frente a Saúde , Relações Interpessoais , Transtornos Mentais , Estereotipagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Educação em Saúde/métodos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários
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