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Leal M.C.,University of Aveiro | Leal M.C.,Skidaway Institute of Oceanography | Puga J.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Serodio J.,University of Aveiro | And 2 more authors.
PLoS ONE | Year: 2012

It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI) over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990-2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively). Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no commercial value, may become highly valuable in the ongoing search for new drugs from the sea. © 2012 Leal et al. Source

Luis A.T.,University of Aveiro | Coelho H.,University of Aveiro | Coelho H.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Almeida S.F.P.,University of Aveiro | And 2 more authors.
Fundamental and Applied Limnology | Year: 2013

The surrounding streams of the Aljustrel mining area (Alentejo Region, Southern Portugal) are strongly affected by acid mine drainage (AMD), as a result of the weathering of the tailing's sulphide minerals. Benthic diatoms (Bacillariophyceae) and water samples were collected seasonally, during one year (2008/09), at 13 sampling sites (5 impacted and 8 unimpacted). Benthic diatom assemblages were studied using Pulse Amplitude Modulated (PAM) fluorometry to assess the effects of the metals/acidity on the photosynthetic efficiency. The information provided by Chl-a fluorescence parameters (e.g. α, ETR max) is an early warning signal of biological effects after acute exposure to chemicals, damaging either directly or indirectly Photosystem II (PSII). Statistical analysis (Two-way and Factorial ANOVAs) found significant differences on Chl-a fluorescence parameters of impacted and unimpacted sites. Photosynthetic efficiency and biomass (Chl-a) were lower for benthic diatom assemblages in impacted streams (Água Forte and Água Azeda), especially during summer, due to very low pH (2.3) and the concentration effect of Cu (348 ppm), Fe (6173 ppm) and Zn (1728 ppm) in waters and sediments. Diatom diversity was low at these sites, mainly dominated by Pinnularia aljustrelica, the main contributor to the high similarity between impacted sites (81 % of similarity by SIMPER). This is a typical species from acidic waters with high metal concentrations. Maximum values of Chl-a fluorescence parameters (α, ETRmax) were found for winter at the unimpacted sites in the Canal da Barrada and Roxo streams due to: 1) higher distance from mine input, 2) pH differences, 3) the existence of brackish/marine species (e.g. Entomoneis paludosa and Haslea spicula), supported by high ions content in the waters. When the analysis was based on the structure of diatom assemblages dominated by Achnanthidium minutissimum, two groups were highlighted: JU-PB and RJ-BF (uncontaminated), indicating seasonal differences. This study confirmed PAM fluorescence as an effective method for the rapid and non-destructive estimation of photosynthetic performance in diatom communities of AMD impacted streams from pyritic mining areas. © 2013 E. Schweizerbart'sche Verlagsbuchhandlung. Source

Paula J.J.S.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Bispo R.M.B.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Bispo R.M.B.,ISPA University | Leite A.H.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | And 5 more authors.
Wildlife Research | Year: 2014

Context To assess the real impact of human-made structures on bird and bat communities, a significant number of carcass-removal trials has been performed worldwide in recent decades. Recently, researchers have started to use camera traps to record carcasses exact removal time and better understand the factors that influence this event. Aims In our study, we endeavoured to identify the factors that significantly affect carcass-persistence time, such as (1) season, (2) scavenger guild, (3) type of carcass, (4) habitat and (5) weather conditions. Additionally, we aimed to assess the performance of camera-trapping technology in comparison to the conventional method typically used in carcass-removal trials. Methods We conducted two trials in two wind farms during early spring and during summer season. In each trial, we used 30 bird carcasses and 30 mice carcasses as surrogates for bats. Digital infrared camera traps were used to monitor each carcass. Chi-squared test was used to investigate differences between wind farms regarding the scavenger guild. A log-rank test was used to compare carcass-persistence times for both wind farms. Carcass-persistence times were analysed using both non-parametric and parametric survival models. Finally, we evaluated the percentage of carcasses removed during the day time and night time. Key results In our study area, carcass-persistence times were influenced by the scavenger guild present and by the exposure to rain. Camera traps allowed to record the exact removal time for the majority of the carcasses, reducing the number of visits to the study site about five times. However, there were also cases wherein loss of data occurred as a result of equipment flaws or camera theft. Conclusions Results demonstrated the importance of undertaking site-specific carcass-removal trials. Use of camera-trap methodology is a valid option, reducing displacement costs. Costs related to equipment purchase and the risk of camera theft should be taken into consideration. Implications When choosing camera-trapping, the main aspect to evaluate is the balance between the investment in equipment purchase and the cost savings through reduced displacement costs. Further studies are required concerning the real effects of the data collected on the accuracy of carcass-removal correction factor obtained. © CSIRO 2014. Source

Bernardino J.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Bispo R.,Instituto Superior Of Psicologia Aplicada | Torres P.,Bio3 Estudos e Projectos em Biologia e Valorizacao de Recursos Naturais Lda. | Rebelo R.,University of Lisbon | And 2 more authors.
Wildlife Biology in Practice | Year: 2011

During the last years there has been a significant worldwide increase in the number of wind farms. This kind of energy can have negative impacts, such as the direct mortality or lethal injury of birds and bats caused by collision with wind turbines. In order to evaluate bird (or bat) mortality regarding wind power generation facilities, strict monitoring protocols are required which must take into account the possibility of carcass removal by scavenging animals or decomposition before the monitoring session. For this purpose, carcass removal trials with 180 carcasses representing three size classes (small, medium and large) were conducted in two seasons (Spring and Autumn) at three wind farms located in the central region of Portugal. No significant differences were found between removal rates of different wind farms or size classes contrarily to seasons, which presented an average carcass removal time of 3.9 and 4.6 days, respectively for Spring and Autumn. The results of the present study showed the importance of trials to estimate the carcass removal rates, which influences the survey effort management and consequently the monitoring protocols. The experimental design for future trials in the same region should account for season effect and be conducted using daily checks of the carcasses for, at least, 15 days. © 2011 J. Bernardino, R. Bispo, P. Torres, R. Rebelo, M. Mascarenhas & H. Costa. Source

Santos H.,University of Porto | Juste J.,CSIC - Donana Biological Station | Ibanez C.,CSIC - Donana Biological Station | Palmeirim J.M.,University of Lisbon | And 10 more authors.
Biological Journal of the Linnean Society | Year: 2014

To determine what shapes the distributions of cryptic species, we aimed to unravel ecological niches and geographical distributions of three cryptic bat species complexes in Iberia, Plecotus auritus/begognae, Myotis mystacinus/alcathoe and Eptesicus serotinus/isabellinus (with 44, 69, 66, 27, 121 and 216 records, respectively), considering ecological interactions and biogeographical patterns. Species distribution models (SDMs) were built using a presence-only technique (Maxent), incorporating genetically identified species records with environmental variables (climate, habitat, topography). The most relevant variables for each species' distribution and respective response curves were then determined. SDMs for each species were overlapped to assess the contact zones within each complex. Niche analyses were performed using niche metrics and spatial principal component analyses to study niche overlap and breadth. The Plecotus complex showed a parapatric distribution, although having similar biogeographical affinities (Eurosiberian), possibly explained by competitive exclusion. The Myotis complex also showed Eurosiberian affinities, with high overlap between niches and distribution, suggesting resource partitioning between species. Finally, E.serotinus was associated with Eurosiberian areas, while E.isabellinus occurred in Mediterranean areas, suggesting possible competition in their restricted contact zone. This study highlights the relevance of considering potential ecological interactions between similarly ecological species when assessing species distributions. © 2014 The Linnean Society of London. Source

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