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Clemencio C.,University of Aveiro | Viegas M.,Investigation Unit for Governance | Viegas M.,University of Aveiro | Nadais H.,University of Aveiro | Nadais H.,Center for Environmental and Marine Studies
Science of the Total Environment | Year: 2014

The livestock production is a strategic and crucial activity for it fixes populations in rural areas, contributing to its conservation, and most importantly because it ensures food production. By producing meat, milk or eggs, this sector contributes to national food self-sufficiency. However, intensive livestock farming activities carry a strong pollution load on the environment, particularly through the emission of nitrogen (N), phosphorus (P), and greenhouse gases (GHG).The Baixo Vouga region in Portugal due to its climatic conditions and soil characteristics holds a high number of livestock production units mainly cattle, poultry and swine. Thus such an activity contributes to a significant portion of the wealth created in this region. This high potential has collided with the existence of environmentally sensitive areas, many of which are protected by European environmental regulations.This work studies the geographical distribution of livestock population of cattle, poultry and swine in the Baixo Vouga region and quantifies its impacts on the environment by calculating the excretion loads of N and P of these species. In the cattle and poultry sectors two clusters or agglomerations are identified, the first in the northern region and the second in the inland region. Moreover, the cattle farming cluster overlaps on vulnerable zones requiring specific monitoring on effluent treatment issues. © 2014 Elsevier B.V. Source


Sousa J.,Oxford Brookes University | Sousa J.,Center for Research in Anthropology | Sousa J.,Center for Environmental and Marine Studies | Luz A.L.,University of Lisbon | And 5 more authors.
Agroecology and Sustainable Food Systems | Year: 2015

Outside of agroforestry disciplines, “orchards” and “forests” are usually studied through different fields of knowledge or are mired in conflicting views. Our study aimed to provide preliminary information on regeneration in cashew orchards by studying the effect of previous land cover, the surrounding landscape, and orchards’ age on the density of species and number of plants. We followed linear transects in orchards planted in areas previously covered by savannah and forest. We found typical forest species growing in the understory, even in orchards previously occupied by savannah or as old as 42 years. The density of species is higher in orchards planted in previously forested plots and in more forested environments. Species density in the understory decreases as orchards get older, but it seems that it increases again after a certain age threshold. This study shows that cashew orchards in Cantanhez retain their potential for succession to forest, and highlights the continuum that may exist between orchards and forests. More research is needed to assess a possible “forestization” of the savannahs through cashew plantations. © , Copyright © Taylor & Francis Group, LLC. Source


Vieira D.C.S.,Center for Environmental and Marine Studies | Fernandez C.,Research Center Forestal Of Lourizan | Vega J.A.,Research Center Forestal Of Lourizan | Keizer J.J.,Center for Environmental and Marine Studies
Journal of Hydrology | Year: 2015

Soil burn severity has been widely used to describe the impacts of fire on soils and is increasingly being recognised as a decisive factor controlling post-fire erosion rates. However, there is no unique definition of the term and the relationship between soil burn severity and post-fire hydrological and erosion response has not yet been fully established. The objective of this work was to review the existing literature on the role of soil burn severity on post-fire runoff and erosion ratios. To this end, a meta-analysis was carried out of the runoff and inter-rill erosion data from field rainfall simulation experiments (RSE's) that compared burnt and unburnt conditions. In this study, 109 individual observations were analysed that covered a wide geographical range, various types of land cover (forest, shrubland, and grassland) and two types of fire types (wildfire and prescribed fire). The effect size of the post-fire runoff and erosion response was determined for four key factors: (i) soil burn severity; (ii) time-since-fire; (iii) rainfall intensity; and (iv) bare soil cover. Statistical meta-analysis showed that fire occurrence had a significant effect on the hydrological and erosive response. However, this effect was only significantly higher with increasing soil burn severity for inter-rill erosion, and not for runoff. This study furthermore highlighted the incoherencies between existing burn severity classifications, and proposed an unambiguous classification. © 2015 Elsevier B.V. Source


Vieira D.C.S.,Center for Environmental and Marine Studies | Malvar M.C.,Center for Environmental and Marine Studies | Fernandez C.,Research Center Forestal Of Lourizan | Serpa D.,Center for Environmental and Marine Studies | Keizer J.J.,Center for Environmental and Marine Studies
Geomorphology | Year: 2016

The impacts of forest fires on runoff and soil erosion have been assessed by many studies, so the effects of fires on the hydrological and geomorphological processes of burnt forest areas, globally and in the Mediterranean region, are well established. Few studies, however, have assessed post-fire runoff and erosion on large time scales. In addition, a limited number of studies are available that consider the effect of pre-fire land management practices on post-fire runoff and erosion. This study evaluated annual runoff and sediment losses, at micro plot scale, for 4 years after a wildfire in three eucalypt plantations with different pre-fire land management practices (i.e., plowed and unplowed). During the four years following the fire, runoff amounts and coefficients at the downslope plowed (1257 mm, 26%) and contour plowed eucalypt sites (1915 mm, 40%) were higher than at the unplowed site (865 mm, 14%). Sediment losses over the 4 years of study were also consistently higher at the two plowed sites (respectively, 0.47 and 0.83 Mg ha− 1 y− 1 at the downslope and contour plowed eucalypt site) than at the unplowed site (0.11 Mg ha− 1 y− 1). Aside from pre-fire land management, time-since-fire also seemed to significantly affect post-fire annual runoff and erosion. In general, annual runoff amounts and erosion rates followed the rainfall pattern. Runoff amounts presented a peak during the third year of monitoring while erosion rates reached their maximum one year earlier, in the second year. Runoff coefficients increased over the 4 years of monitoring, in disagreement to the window of disturbance post-fire recovery model, but sediment concentrations decreased over the study period. When compared with other long-term post-fire studies and with studies evaluating the effects of pre- and post-fire management practices, the results of the present work suggest that an ecosystem's recovery after fire is highly dependent on the background of disturbances of each site, as runoff and erosion values were higher at the plowed sites than at the unplowed site. © 2016 Elsevier B.V. Source


Sousa J.,New University of Lisbon | Sousa J.,University of Lisbon | Sousa J.,Oxford Brookes University | Sousa J.,Center for Environmental and Marine Studies | And 8 more authors.
American Journal of Primatology | Year: 2014

Our study concerns local knowledge and perceptions of chimpanzees among farming communities within Cantanhez National Park, Guinea-Bissau. We submitted a survey questionnaire to 100 people living in four villages in the Park to enquire about their knowledge of chimpanzee ecology and human-chimpanzee interactions. Local farmers live in close contact with chimpanzees, consider them to be more similar to humans than any other species, and attribute special importance to them primarily due to expectations of tourism revenue. Interviewees' responses, as a function of gender, village, and age, were analyzed statistically using non-parametric tests (Mann-Whitney and Kruskal-Wallis). Age influenced responses significantly, while gender and village had no significant effect. Youngsters emphasized morphological aspects of human-chimpanzee similarities, while adults emphasized chimpanzee behavior and narratives about the shared history of humans and chimpanzees. Tourism, conservation, and crop raiding feature prominently in people's reports about chimpanzees. Local people's engagement with conservation and tourism-related activities is likely to allow them to manage not only the costs but also the benefits of conservation, and can in turn inform the expectations built upon tourism. © 2013 Wiley Periodicals, Inc. Source

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