Guardiola M., Pino J., Roda F. (2013) Patch history and spatial scale modulate local plant extinction and extinction debt in habitat patches. Diversity and Distributions. 19: 825-833.EnllaçDoi: 10.1111/ddi.12045
Aim: Many species exhibit a time-lag between habitat loss and its extinction, resulting in extinction debt. Although extinction debt is considered a widespread phenomenon, differences in methodological approaches can affect its detection. We aim to contribute to this methodological debate by exploring whether extinction debt is either a phenomenon common to all patches or idiosyncratic to the patch and landscape attributes of a given patch. We also aim to determine whether the scale dependency of species richness might help to explain extinction debt. Location: Southern Catalonia (NE Iberian Peninsula). Methods: We studied the effects of habitat loss on plant species richness (total, specialists and generalists) in stable (habitat loss
Guedot C., Buckner J.S., Hagen M.M., Bosch J., Kemp W.P., Pitts-Singer T.L. (2013) Nest marking behavior and chemical composition of olfactory cues involved in nest recognition in Megachile rotundata. Environmental Entomology. 42: 779-789.EnllaçDoi: 10.1603/EN13015
In-nest observations of the solitary bee, Megachile rotundata (F.), revealed that nesting females apply olfactory cues to nests for nest recognition. On their way in and out of the nest, females drag the abdomen along the entire length of the nest, and sometimes deposit fluid droplets from the tip of the abdomen. The removal of bee-marked sections of the nest resulted in hesitation and searching behavior by females, indicating the loss of olfactory cues used for nest recognition. Chemical analysis of female cuticles and the deposits inside marked nesting tubes revealed the presence of hydrocarbons, wax esters, fatty aldehydes, and fatty alcohol acetate esters. Chemical compositions were similar across tube samples, but proportionally different from cuticular extracts. These findings reveal the importance of lipids as chemical signals for nest recognition and suggest that the nest-marking cues are derived from a source in addition to, or other than, the female cuticle. © 2013 Entomological Society of America.
Guisan A., Tingley R., Baumgartner J.B., Naujokaitis-Lewis I., Sutcliffe P.R., Tulloch A.I.T., Regan T.J., Brotons L., Mcdonald-Madden E., Mantyka-Pringle C., Martin T.G., Rhodes J.R., Maggini R., Setterfield S.A., Elith J., Schwartz M.W., Wintle B.A., Broennimann O., Austin M., Ferrier S., Kearney M.R., Possingham H.P., Buckley Y.M. (2013) Predicting species distributions for conservation decisions. Ecology Letters. 16: 1424-1435.EnllaçDoi: 10.1111/ele.12189
Species distribution models (SDMs) are increasingly proposed to support conservation decision making. However, evidence of SDMs supporting solutions for on-ground conservation problems is still scarce in the scientific literature. Here, we show that successful examples exist but are still largely hidden in the grey literature, and thus less accessible for analysis and learning. Furthermore, the decision framework within which SDMs are used is rarely made explicit. Using case studies from biological invasions, identification of critical habitats, reserve selection and translocation of endangered species, we propose that SDMs may be tailored to suit a range of decision-making contexts when used within a structured and transparent decision-making process. To construct appropriate SDMs to more effectively guide conservation actions, modellers need to better understand the decision process, and decision makers need to provide feedback to modellers regarding the actual use of SDMs to support conservation decisions. This could be facilitated by individuals or institutions playing the role of 'translators' between modellers and decision makers. We encourage species distribution modellers to get involved in real decision-making processes that will benefit from their technical input; this strategy has the potential to better bridge theory and practice, and contribute to improve both scientific knowledge and conservation outcomes. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.
Gutiérrez F., Gárriz M., Peri J.M., Ferraz L., Sol D., Navarro J.B., Barbadilla A., Valdés M. (2013) Fitness costs and benefits of personality disorder traits. Evolution and Human Behavior. 34: 41-48.EnllaçDoi: 10.1016/j.evolhumbehav.2012.09.001
Extreme personality traits in humans often have detrimental life consequences, so they have long been supposed to be diseases. However, many other species display personality variants that are maintained due to their fitness advantages; in this case, they are construed as strategies. To examine the fitness costs and benefits of pathological personality traits in humans, we measured features of the A (socially odd, distrustful), B (incentive-seeking, selfish) and C (fearful, inhibited) clusters with the Personality Diagnostic Questionnaire-4. + (PDQ-4. +) in a sample of 738 outpatients. Fitness relevant parameters like mating success, reproductive output, self preservation, and access to status were assessed with the Life Outcome Questionnaire. No fitness advantages were found for high-A subjects. In contrast, high-B subjects tripled low-B subjects with regard to mating success and had 39% more offspring. Further, high-C subjects outperformed low-C subjects in attaining status and avoiding risks. These findings help explain the commonness of some extreme personality traits in humans, and suggest that they should be seen as evolutionary strategies rather than as diseases. © 2013 Elsevier Inc.
Guèze M., Paneque-Gálvez J., Luz A.C., Pino J., Orta-Martínez M., Reyes-García V., Macía M.J. (2013) Determinants of tree species turnover in a southern Amazonian rain forest. Journal of Vegetation Science. 24: 284-295.EnllaçDoi: 10.1111/j.1654-1103.2012.01461.x
Questions: What is the relative importance of environmental variables and geographical distances to explain tree species turnover? Are these patterns consistent for different tree categories, i.e. all trees (DBH ≥ 2.5 cm), large trees (DBH ≥ 10 cm), small trees sensu lato (DBH
Harrison S.P., Morfopoulos C., Dani K.G.S., Prentice I.C., Arneth A., Atwell B.J., Barkley M.P., Leishman M.R., Loreto F., Medlyn B.E., Niinemets U., Possell M., Peñuelas J., Wright I.J. (2013) Volatile isoprenoid emissions from plastid to planet. New Phytologist. 197: 49-57.EnllaçDoi: 10.1111/nph.12021
Approximately 1-2% of net primary production by land plants is re-emitted to the atmosphere as isoprene and monoterpenes. These emissions play major roles in atmospheric chemistry and air pollution-climate interactions. Phenomenological models have been developed to predict their emission rates, but limited understanding of the function and regulation of these emissions has led to large uncertainties in model projections of air quality and greenhouse gas concentrations. We synthesize recent advances in diverse fields, from cell physiology to atmospheric remote sensing, and use this information to propose a simple conceptual model of volatile isoprenoid emission based on regulation of metabolism in the chloroplast. This may provide a robust foundation for scaling up emissions from the cellular to the global scale. © 2012 New Phytologist Trust.
Herrera J.M., Doblas-Miranda E. (2013) Land-cover change effects on trophic interactions: Current knowledge and future challenges in research and conservation. Basic and Applied Ecology. 14: 1-11.EnllaçDoi: 10.1016/j.baae.2012.11.008
Understanding the effects of land-cover alterations on ecosystem functioning has become a major challenge in ecological research during the last decade. This has stimulated a rapid growth in research investigating the links between land-cover change and biotic interactions, but to date no study has evaluated the progress towards achieving this scientific goal. With the aim of identifying gaps in current knowledge and challenging research areas for the future, we reviewed the scientific literature published during the last decade (1998-2010) investigating land-cover change effects on trophically-mediated biotic interactions. Our results reveal a disproportionate focus on particular trophic interactions and ecosystem types. Furthermore, in most cases, the measurement of trophic interactions is carried out neglecting the identity of the interacting species and the interrelation between the type of land-cover change effects. Finally, inappropriate temporal scales are applied to cope with spatiotemporal resource fluctuations for the interacting species. We suggest that the ongoing patterns and trends of research hamper efforts to achieve a truly comprehensive understanding of the effects of land-cover alterations on trophic interactions, and hence on ecosystem functioning in human-impacted landscapes. We therefore recommend alternative research trends and indicate gaps in current knowledge that need to be filled. Furthermore, we highlight that these biases could also limit the effectiveness of management actions aimed at ensuring the resilience and long-term conservation of natural habitats worldwide. © 2012 Gesellschaft für Ökologie.
Izquierdo R., Alarcón M., Àvila A. (2013) WeMO effects on the amount and the chemistry of winter precipitation in the north-eastern Iberian Peninsula. Tethys. 10: 45-51.EnllaçDoi: 10.3369/tethys.2013.10.05
The cluster classification of provenances at a site in the NE Iberian Peninsula indicated that in the period of extended winter (December to March, DJFM) fast Atlantic air flows correspond to positive WeMO index (WeMOi), while negative WeMOi are associated to Mediterranean circulations. The amount of winter precipitation was inversely correlated with winter WeMOi. Wet deposition fluxes of marine-derived (Na+, Mg2+ and Cl-) and anthropogenic-derived (NO3 - and K+) ions were significantly (and negatively) related to winter WeMOi. The negative phase of WeMO causes the entry of air masses from the Mediterranean into the Iberian Peninsula, that are enriched with marine ions. For NO3 - this result suggests the advection over the Mediterranean of polluted air masses from southern Europe and the scavenging and deposition of this pollution by rain during WeMO negative phases. This will carry long-range pollutants to the NE Iberian Peninsula, but local pollutants may also contribute, as precipitation events from the Mediterranean (associated to negative WeMOi) may incorporate local anthropogenic emissions that build up during the winter anticyclonic episodes typical of the region. © BY 2013 Author(s).
Kefauver S.C., Penuelas J., Ustin S. (2013) Using topographic and remotely sensed variables to assess ozone injury to conifers in the Sierra Nevada (USA) and Catalonia (Spain). Remote Sensing of Environment. 139: 138-148.EnllaçDoi: 10.1016/j.rse.2013.07.037
The capacity to remotely identify impacts of ozone on conifers in California, USA and Catalonia, Spain was investigated using remote sensing and terrain-driven GIS analyses related to plant water relations and ozone uptake. The Ozone Injury Index (OII) field metric applied to Pinus ponderosa and Pinus jeffreyi in the USA and adapted to Pinus uncinata in Spain included visible chlorotic mottling, needle retention, needle length, and crown depth. Species classifications of AVIRIS and CASI hyperspectral imagery all approached 80% overall accuracy for the target bioindicator species. Remote sensing vegetation indices correlated best with longer-wavelength SWIR indices from the AVIRIS data in California, with the exception of the Photosynthetic Reflectance Index (PRI) correlation with the OII Visual Component (OIIVI), which was also the highest direct correlation in Catalonia. In Catalonia, the OIIVI alone and its subparts correlated better with the CASI data than with the full OII, namely the PRI (R2=0.28, p=0.0044 for OIIVI-amount and R2=0.33 and p=0.0016 for OIIVI-severity). Stepwise regression models of ozone injury developed using remote sensing indices combined with terrain-derived GIS variables were significant for OII in California (R2=0.59, p<0.0001) and in Catalonia (R2=0.68, p<0.0001 for OIIVI). Multiple regression models of ozone injury including a three year average of O3 exposure were significant both with imaging spectroscopy indices alone (R2=0.56, p<0.0001) and with topographic variables added (R2=0.77, p<0.0001) in Catalonia. Applying the multivariate models to image classifications could provide useful maps useful for ozone impact monitoring but requires further validation before being considered operational. © 2013 Elsevier Inc.
Kindermann G.E., Schörghuber S., Linkosalo T., Sanchez A., Rammer W., Seidl R., Lexer M.J. (2013) Potential stocks and increments of woody biomass in the European Union under different management and climate scenarios. Carbon Balance and Management. 8: 0-0.EnllaçDoi: 10.1186/1750-0680-8-2
Background: Forests play an important role in the global carbon flow. They can store carbon and can also provide wood which can substitute other materials. In EU27 the standing biomass is steadily increasing. Increments and harvests seem to have reached a plateau between 2005 and 2010. One reason for reaching this plateau will be the circumstance that the forests are getting older. High ages have the advantage that they typical show high carbon concentration and the disadvantage that the increment rates are decreasing. It should be investigated how biomass stock, harvests and increments will develop under different climate scenarios and two management scenarios where one is forcing to store high biomass amounts in forests and the other tries to have high increment rates and much harvested wood.Results: A management which is maximising standing biomass will raise the stem wood carbon stocks from 30 tC/ha to 50 tC/ha until 2100. A management which is maximising increments will lower the stock to 20 tC/ha until 2100. The estimates for the climate scenarios A1b, B1 and E1 are different but there is much more effect by the management target than by the climate scenario. By maximising increments the harvests are 0.4 tC/ha/year higher than in the management which maximises the standing biomass. The increments until 2040 are close together but around 2100 the increments when maximising standing biomass are approximately 50 % lower than those when maximising increments. Cold regions will benefit from the climate changes in the climate scenarios by showing higher increments.Conclusions: The results of this study suggest that forest management should maximise increments, not stocks to be more efficient in sense of climate change mitigation. This is true especially for regions which have already high carbon stocks in forests, what is the case in many regions in Europe. During the time span 2010-2100 the forests of EU27 will absorb additional 1750 million tC if they are managed to maximise increments compared if they are managed to maximise standing biomass. Incentives which will increase the standing biomass beyond the increment optimal biomass should therefore be avoided. Mechanisms which will maximise increments and sustainable harvests need to be developed to have substantial amounts of wood which can be used as substitution of non sustainable materials. © 2013 Kindermann et al.; licensee BioMed Central Ltd.
Dona't d'alta al Newsletter per rebre totes les novetats del CREAF al teu e-mail.
© 2016 CREAF | Avís legal