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Torres J.,University of Porto | Brito J.C.,Institute Ciencias Agrarias Of Vairao | Vasconcelos M.J.,Instituto Investigacao Cientifica Tropical | Catarino L.,Instituto Investigacao Cientifica Tropical | Honrado J.,University of Porto
Biological Conservation | Year: 2010

Pan troglodytes verus is considered one of the most endangered primates in the world due to habitat loss or degradation, and it is considered extinct in several regions of West-Africa. This study aims at developing a model that predicts habitat suitability for chimpanzee under different land cover scenarios and supports a multi-temporal analysis of the recent habitat evolution in southern Guinea-Bissau. The model, built using a maximum entropy framework, is spatially explicit, uses eco-geographic variables derived from landscape compositional, structural and functional attributes, and is based on nest location data collected in the field. The results show that the developed model has good levels of reliability and the map produced through its application reveals a current extension of 752 km2 of adequate habitat in a 2723 km2 study area. Forest related EGVs (ecogeographical variables) had the higher importance for the model production. Habitat suitability maps produced for three dates in the last three decades show that there has been a marked decrease in habitat extension and in connectivity to neighbouring regions. We analyse the implications of these results in possible strategies for the conservation of chimpanzees in Guinea-Bissau. © 2009 Elsevier Ltd. All rights reserved.


PubMed | Instituto Investigacao Cientifica Tropical, University of Lisbon, Federal University of Espirito Santo, New University of Lisbon and 3 more.
Type: Journal Article | Journal: Global change biology | Year: 2016

The tropical coffee crop has been predicted to be threatened by future climate changes and global warming. However, the real biological effects of such changes remain unknown. Therefore, this work aims to link the physiological and biochemical responses of photosynthesis to elevated air [CO2 ] and temperature in cultivated genotypes of Coffea arabica L. (cv. Icatu and IPR108) and Coffea canephora cv. Conilon CL153. Plants were grown for ca. 10 months at 25/20C (day/night) and 380 or 700 l CO2 l(-1) and then subjected to temperature increase (0.5C day(-1) ) to 42/34C. Leaf impacts related to stomatal traits, gas exchanges, C isotope composition, fluorescence parameters, thylakoid electron transport and enzyme activities were assessed at 25/20, 31/25, 37/30 and 42/34C. The results showed that (1) both species were remarkably heat tolerant up to 37/30C, but at 42/34C a threshold for irreversible nonstomatal deleterious effects was reached. Impairments were greater in C. arabica (especially in Icatu) and under normal [CO2 ]. Photosystems and thylakoid electron transport were shown to be quite heat tolerant, contrasting to the enzymes related to energy metabolism, including RuBisCO, which were the most sensitive components. (2) Significant stomatal trait modifications were promoted almost exclusively by temperature and were species dependent. Elevated [CO2 ], (3) strongly mitigated the impact of temperature on both species, particularly at 42/34C, modifying the response to supra-optimal temperatures, (4) promoted higher water-use efficiency under moderately higher temperature (31/25C) and (5) did not provoke photosynthetic downregulation. Instead, enhancements in [CO2 ] strengthened photosynthetic photochemical efficiency, energy use and biochemical functioning at all temperatures. Our novel findings demonstrate a relevant heat resilience of coffee species and that elevated [CO2 ] remarkably mitigated the impact of heat on coffee physiology, therefore playing a key role in this crop sustainability under future climate change scenarios.


Araujo J.A.,RAIZ Forest and Paper Research Institute | Borralho N.M.G.,BorralhoIdea Consulting | Borralho N.M.G.,University of Lisbon | Borralho N.M.G.,Instituto Investigacao Cientifica Tropical | Dehon G.,RAIZ Forest and Paper Research Institute
Tree Genetics and Genomes | Year: 2012

The paper investigates the importance of additive and non-additive genetic variances for growth in Eucalyptus globulus (Tasmanian Blue Gum), based on a large collection of diameter growth data covering 40 sites and more than 4,200 genotypes, most of them cloned, and spanning three generations of breeding. The variance estimates were based on a model accounting for additive, full-sib family and clone within full-sib family terms. The results indicated a small amount of additive genetic variance for diameter(ĥ 2=0.10) and although non-additive genetic variance was also small, it accounted for a significant proportion of the total genetic variance present, corresponding to 80% of the additive variance. The interpretation of these non-additive effects is difficult. The results suggest, however, a possible role of epistasis. The evidence for this came from a strong observed bias in additive variance when clone effects were removed from the model and a larger than expected variance due to full-sib families relative to the variance due to clones within family. The relatively large proportion of genetic variance for growth that seems to be due to non-additive genetic effects has obvious implications in the breeding and deployment options in eucalypts, and these are briefly discussed. © 2011 Springer-Verlag.


Nogueira H.,University of Coimbra | Gama A.,University of Coimbra | Gama A.,University of Lisbon | Mourao I.,University of Trás os Montes e Alto Douro | And 4 more authors.
American Journal of Human Biology | Year: 2013

Objectives: This study analyses the associations between children's obesity, sports activity (SA), and perceived environmental characteristics with the children's SES. Methods: A sample of 1,885 Portuguese children, aged 3-10 years, living in Coimbra, Portugal, was observed. Weight and height were measured and obesity was defined by age-and sex-specific, BMI cut-off points. Questionnaires included variables on SA levels, SES and parental neighborhood perceptions were done. A CATPCA was performed and two neighborhood dimensions were achieved. The independent associations of SES with obesity, SA and perceived neighborhood dimensions was analyzed using ordered logistic regressions. Results: Children of low [odds ratio (OR)=1.76; confidence interval (CI)=1.25-1.99] and medium SES (OR=1.57; CI=1.34-2.33) were more likely to be obese than their high-SES peers, less likely to participate in SA (low SES OR=0.177; CI=0.12-0.26; medium SES OR=0.357; CI=0.24-0.53), and their parents were less likely to have positive perceptions of their built environment (low SES OR=0.516; CI=0.38-0.70; medium SES OR=0.565; CI=0.37-0.86). Conclusions: Obesity increases and SA decreases among children with the lowest SES and these living in neighborhoods with higher perceived risk. This finding suggests a model of environmental injustice, whereby differential access to the neighborhood's resources overlaps with familial socioeconomic disadvantage. © 2013 Wiley Periodicals, Inc.


Ramalho R.S.,University of Bristol | Ramalho R.S.,Lamont Doherty Earth Observatory | Brum Da Silveira A.,University of Lisbon | Fonseca P.E.,University of Lisbon | And 6 more authors.
Geochemistry, Geophysics, Geosystems | Year: 2015

The transition from seamount to oceanic island typically involves surtseyan volcanism. However, the geological record at many islands in the NE Atlantic - all located within the slow-moving Nubian plate - does not exhibit evidence for an emergent surtseyan phase but rather an erosive unconformity between the submarine basement and the overlying subaerial shield sequences. This suggests that the transition between seamount and island may frequently occur by a relative fall of sea level through uplift, eustatic changes, or a combination of both, and may not involve summit volcanism. In this study, we explore the consequences for island evolutionary models using Madeira Island (Portugal) as a case study. We have examined the geologic record at Madeira using a combination of detailed fieldwork, biostratigraphy, and 40Ar/39Ar geochronology in order to document the mode, timing, and duration of edifice emergence above sea level. Our study confirms that Madeira's subaerial shield volcano was built upon the eroded remains of an uplifted seamount, with shallow marine sediments found between the two eruptive sequences and presently located at 320-430 m above sea level. This study reveals that Madeira emerged around 7.0-5.6 Ma essentially through an uplift process and before volcanic activity resumed to form the subaerial shield volcano. Basal intrusions are a likely uplift mechanism, and their emplacement is possibly enhanced by the slow motion of the Nubian plate relative to the source of partial melting. Alternating uplift and subsidence episodes suggest that island edifice growth may be governed by competing dominantly volcanic and dominantly intrusive processes. © 2015. American Geophysical Union. All Rights Reserved.


Nogueira H.,University of Coimbra | Gama A.,University of Coimbra | Gama A.,University of Lisbon | Mourao I.,University of Trás os Montes e Alto Douro | And 3 more authors.
WIT Transactions on Ecology and the Environment | Year: 2014

People of low socioeconomic status (SES) are more likely to live in disadvantaged neighbourhoods, where resources and facilities that might support healthy living are scarce, while harmful environmental aspects are abundant. Our aim was to analyse the associations between children’s body mass index (BMI), children’s sports activity (SA) and perceived environmental characteristics with the children’s SES. The sample included 1885 children, aged 3–10 years, living in Coimbra, Portugal. Overweight and obesity were defined using age and sexspecific BMI cut-off points, as defined by International Obesity Task Force (IOTF). SA levels, SES and parental neighbourhood perceptions were assessed through questionnaires. Environmental data were reduced through a Principal Component Analysis for Categorical Data (CATPCA), and two neighbourhood dimensions were achieved. The independent associations of SES, the main predictor, with BMI, SA and perceived neighbourhood dimensions was analysed using ordered logistic regressions. Our results showed that children of low and medium SES were more likely to be obese than their high-SES peers, children from low and medium SES groups were less likely to participate in SA; parents of children from low and medium SES groups were less likely to have positive perceptions of their built environment. We concluded that low SES children are more obese, more sedentary and more likely to live in inadequate neighbourhoods, characterized by higher perceived risks. These findings show that the differential access to neighbourhood resources overlaps with familial socioeconomic disadvantage shaping patterns that are detrimental to children’s health and wellbeing. Childhood obesity also results from a model of deprivation amplification that penalizes the most vulnerable children. © 2014 WIT Press.


Nogueira H.,University of Coimbra | Ferrao M.,University of Coimbra | Gama A.,University of Coimbra | Gama A.,University of Lisbon | And 4 more authors.
Health and Place | Year: 2013

This study investigates the links between parents' perceptions of their social and built residential environment and obesity among Portuguese school boys and girls. A total of 1885 children, 952 girls and 933 boys, aged 3.0-10.0 years, were observed. The children's weight and height were measured, and their parents filled out the "Environmental Module" questionnaire of the International Physical Activity Prevalence Study. Age and sex-specific BMI cut-off points were used to define being overweight/obese. Environmental characteristics were combined into 2 composite neighborhood indices that were used as predictors in logistic regression models. Girls living in neighborhoods perceived as having poorly built environmental conditions had increased odds of being obese (OR=1.47; p<0.005), and girls living in neighborhoods perceived as being unsafe and dangerous had also increased odds of being obese (OR=1.339; p<0.005). These relationships were not evident for boys. Improvements in the neighborhood environment could be a strategy for tackling the growing epidemic of childhood obesity and can simultaneously contribute to reduce health iniquities across population subgroups. © 2012 Elsevier Ltd.


Partelli F.L.,Federal University of Espirito Santo | Partelli F.L.,Instituto Investigacao Cientifica Tropical | Batista-Santos P.,Instituto Investigacao Cientifica Tropical | Scotti-Campos P.,Instituto Nacional Of Investigacao Agraria | And 5 more authors.
Environmental and Experimental Botany | Year: 2011

Low temperatures affect many plant physiological and biochemical components, amongst them the lipid phase of membranes. The present work aimed to characterize the lipid composition of chloroplast membranes of three Coffea genotypes, representing three agronomic valuable species (Coffea arabica cv. Icatu, Coffea canephora cv. Conilon clone 02 and Coffea dewevrei), under adequate environmental conditions and to relate its cold tolerance ability to the adjustments triggered during a gradual temperature decrease, after chilling exposure and upon a recovery period. Under adequate temperature (25/20 °C, day/night) the lipid composition of chloroplast membranes was fairly similar amongst the genotypes concerning the total fatty acid (TFA) content and individual FAs (both globally or within the classes), suggesting a close lipid composition amongst Coffea species, which can be considered as " C18:3" plants. Under cold exposure and subsequent recovery the genotypes undergo adjustments, some of them with acclimation potential. The genotypes displayed some ability to increase lipid synthesis, increasing their FA content. However, under cold exposure (even at 4 °C), Icatu and C. dewevrei plants performed qualitative adjustments, including preferential synthesis of phospholipids (especially PG) instead of galactolipids and increases in the unsaturation degree of DGDG and phospholipid classes (PG, PC and PI). Clone 02 maintained almost all lipid characteristics, what explains its higher cold sensitivity. Furthermore, differences that contribute to explain contrasting cold sensitivity in Icatu (more tolerant) and C. dewevrei emerged when analyzing PA content (taken as a stress metabolite) and the FA composition within MGDG and PG classes. C. dewevrei presented the higher increase, absolute value and relative weight of PA, while Icatu was the solely genotype to show a rise in the unsaturation degree of MGDG and PG, displaying as well the highest DBI values for these classes. We conclude that lipid qualitative and quantitative adjustments constitute a flexible mechanism that decisively contributes to cold acclimation in Coffea spp., working in tandem with others that minimize oxidative stress damages. © 2011 Elsevier B.V.


Scotti-Campos P.,Instituto Nacional Of Investigacao Agraria E Veterinaria | Semedo J.N.,Instituto Nacional Of Investigacao Agraria E Veterinaria | Pais I.,Instituto Nacional Of Investigacao Agraria E Veterinaria | Oliveira M.,Instituto Nacional Of Investigacao Agraria E Veterinaria | And 2 more authors.
Emirates Journal of Food and Agriculture | Year: 2014

Wheat is a major staple crop, and its grain yield is affected by heat stress. Such environmental constraint frequently occurs in the main Portuguese wheat producing regions. The aim of this work was to evaluate the impact of high temperatures after anthesis on gas exchanges, chlorophyll a fluorescence, membrane integrity and yield in nine Portuguese old bread wheat varieties. Photosynthetic rate (Pn) reductions occurred in Gentil Rosso, Grécia and Nabão and may result from inactivation of PSII activity, as indicated by decreases in photochemical efficiency under light (Fv'/Fm') and in quantum yield of electron transport (Φe). Results denoted an enhancement/maintenance of photosynthetic ability under heat, expressed by stable stomatal conductance (gs) and higher water use efficiency (WUE) in MEQ and Restauração, increased Pn in MEB and Restauração, and Pn stability in Ruivo. Reduced membrane damage (lower leakage) in Ruivo and MEQ suggested a higher protoplasmic tolerance to heat in these varieties. Control plants of MEQ also presented the highest lipid amount and the less unsaturated membrane lipids (low double bond index), and these traits were unaffected by heat. Ruivo denoted a stimulation of lipid biosynthesis which could have positive implications on thermal tolerance. Increased Pn and WUE, stable gs and abundant lipids in control plants (MEQ, T94, MEB, Restauração) corresponded to kernel yield increases under heat. Physiological traits are expected to contribute to Portuguese wheat breeding programs towards high temperature tolerance.


Reboredo F.H.,New University of Lisbon | Lidon F.,New University of Lisbon | Pessoa F.,New University of Lisbon | Ramalho J.C.,New University of Lisbon | Ramalho J.C.,Instituto Investigacao Cientifica Tropical
Trends in Biotechnology | Year: 2016

This analysis is focused on the effect of the abrupt decline of oil prices on biofuels, particularly second-generation ethanol. The efforts to decrease the production costs of biofuels, especially cellu- losic ethanol (CE), will be greatly threatened if current oil prices remain low, especially since pro- duction is not slowing. Only huge state subsidies could alleviate this threat, but the challenge is to per- suade citizens that this sacrifice is worthwhile. © 2015 Elsevier Ltd.

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