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The effect of soil microtopographic gradients on dry matter yields and species ...

Projeto BIOPAST: o que aprendemos sobre a ecologia das pastagens permanentes se...

As Pastagens Permanentes Semeadas Ricas em Leguminosas (PPSRL) foram desenvolvidas na década de 1970 pelo agrónomo português David Crespo. Este sistema de pastagens caracteriza-se pela mistura de um elevado número de espécies e cultivares pratenses, geralmente com uma predominância de Trifolium subterraneum. Duas causas explicam a sua franca expansão na última década em Portugal: elevada produtividade frente às...

The effects of climate fluctuations and soil heterogeneity on the floristic com...

Sown Biodiverse Permanent Pastures Rich in Legumes (SBPPRL) is a pasture system for Mediterranean climatic areas mixing a large number of pastures species and cultivars, with a predominance of Trifolium subterraneum. Since the nineties, it rapidly expanded in Portugal due to its high dry matter yields (DM) and C sequestration rates in soil organic matter. Although without clear experimental evidence, it is curr...

Influenza infectious dose may explain the high mortality of the second and thir...

BACKGROUND: It is widely accepted that the shift in case-fatality rate between waves during the 1918 influenza pandemic was due to a genetic change in the virus. In animal models, the infectious dose of influenza A virus was associated to the severity of disease which lead us to propose a new hypothesis. We propose that the increase in the case-fatality rate can be explained by the dynamics of disease and by a ...

Quinta da França

Quinta da França (QF) is a farm located in Cova da Beira, Covilhã, which is managed by Terraprima. The farm’s main activities are agriculture and livestock production. Among the fodder crops, the most important are temporary and permanent pastures and annual crops (such as maize, both irrigated and rainfed). Livestock consists of sheep, cows and goats (the latter in smaller numbers). The management of QF privil...

Montanha

O Norte e Centro de Portugal têm uma fisiografia eminentemente montanhosa. A montanha (altitudes > 700 m) ocupa cerca de 11 % (10 000 km2) da superfície emersa de Portugal continental, estando concentrada no Norte e Centro do país. A montanha fornece um diverso leque de serviços dos ecossistemas. As montanhas normalmente são mais biodiversas do que as áreas planas vizinhas (escala > 100 km2) e albergam um biota...

Testing for the survey mode effect on contingent valuation data quality: A case...

This paper addresses the lack of empirical evaluation of the use of web based surveys in the context of contingent valuation surveys. We compare, using a case study, in-person interviews with web based surveys regarding response rate, information additivity effects and respondents' attitudes towards paying. The web based survey had a much lower response (5.1%) than the in-person interviewing (84%). We find the ...

Avaliação ambiental estratégica do programa de desenvolvimento rural de Portuga...

O Programa de Desenvolvimento Rural (PDR) 2007-2013 estabelece o conjunto de medidas, e dentro de cada uma destas as acções e subacções, conducentes ao cumprimento dos objectivos estabelecidos pelo Plano Estratégico Nacional (PEN) de Desenvolvimento Rural 2007-2013. O PEN surge num momento em que a situação do mundo rural português tem apresentado melhorias em termos de bem-estar social, mas ainda assim com per...

Constraints on Dematerialisation and Allocation of Natural Capital along a Sust...

This paper extends the neoclassical growth model with natural capital by introducing two new concepts: allocation of natural capital and materialization. We consider that anthropogenic environmental impact is correlated with the throughput of the economy (materialisation). Materialisation is the material throughput per unit of economic activity. We capture the effect of the reduction of this throughput demateri...