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Garcia de Leon D.,CSIC - Institute for Sustainable Agriculture | Garcia de Leon D.,Laboratorio Internacional en Cambio Global CSIC PUC | Garcia de Leon D.,University of Tartu | Garcia-Mozo H.,University of Cordoba, Spain | And 6 more authors.
Science of the Total Environment | Year: 2015

Pollen allergies are the most common form of respiratory allergic disease in Europe. Most studies have emphasized the role of environmental processes, as the drivers of airborne pollen fluctuations, implicitly considering pollen production as a random walk. This work shows that internal self-regulating processes of the plants (negative feedback) should be included in pollen dynamic systems in order to give a better explanation of the observed pollen temporal patterns. This article proposes a novel methodological approach based on dynamic systems to investigate the interaction between feedback structure of plant populations and climate in shaping long-term airborne Poaceae pollen fluctuations and to quantify the effects of climate change on future airborne pollen concentrations. Long-term historical airborne Poaceae pollen data (30years) from Cordoba city (Southern Spain) were analyzed. A set of models, combining feedback structure, temperature and actual evapotranspiration effects on airborne Poaceae pollen were built and compared, using a model selection approach. Our results highlight the importance of first-order negative feedback and mean annual maximum temperature in driving airborne Poaceae pollen dynamics. The best model was used to predict the effects of climate change under two standardized scenarios representing contrasting temporal patterns of economic development and CO2 emissions. Our results predict an increase in pollen levels in southern Spain by 2070 ranging from 28.5% to 44.3%. The findings from this study provide a greater understanding of airborne pollen dynamics and how climate change might impact the future evolution of airborne Poaceae pollen concentrations and thus the future evolution of related pollen allergies. © 2015 Elsevier B.V.


Gelcich S.,Laboratorio Internacional en Cambio Global CSIC PUC | Gelcich S.,University of Chile | Hughes T.P.,James Cook University | Olsson P.,University of Stockholm | And 11 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2010

Marine ecosystems are in decline. New transformational changes in governance are urgently required to cope with overfishing, pollution, global changes, and other drivers of degradation. Here we explore social, political, and ecological aspects of a transformation in governance of Chile's coastal marine resources, from 1980 to today. Critical elements in the initial preparatory phase of the transformation were (i) recognition of the depletion of resource stocks, (ii) scientific knowledge on the ecology and resilience of targeted species and their role in ecosystem dynamics, and (iii) demonstration-scale experimental trials, building on smaller-scale scientific experiments, which identified new management pathways. The trials improved cooperation among scientists and fishers, integrating knowledge and establishing trust. Political turbulence and resource stock collapse provided a window of opportunity that triggered the transformation, supported by new enabling legislation. Essential elements to navigate this transformation were the ability to network knowledge from the local level to influence the decision-making processes at the national level, and a preexisting social network of fishers that provided political leverage through a national confederation of artisanal fishing collectives. The resultant governance scheme includes a revolutionary national system of marine tenure that allocates user rights and responsibilities to fisher collectives. Although fine tuning is necessary to build resilience of this new regime, this transformation has improved the sustainability of the interconnected social-ecological system. Our analysis of how this transformation unfolded provides insights into how the Chilean system could be further developed and identifies generalized pathways for improved governance of marine resources around the world.


Marin A.,University of Chile | Marin A.,University of Stockholm | Marin A.,University of Manitoba | Gelcich S.,University of Chile | And 4 more authors.
Ecology and Society | Year: 2012

Comanagement success relies on the proper administration of resources and on the capacity of users to establish and maintain positive social relationships with multiple actors. We assessed multifunctional relationships of small-scale artisanal fisher organizations engaged in a coastal benthic resources comanagement system in Chile to explore bridging and linking social capital, using an egocentric network approach. The formal leaders of 38 small-scale fisher organizations were surveyed to investigate (1) similarities and differences in social capital among fisher organizations and regions, and (2) possible effects of social capital levels on comanagement performance. Results show that the best performing fisher organizations are those with higher levels of linking and bridging social capital. Positive and strong correlations exist between linking social capital levels and comanagement performance variables. Importantly, fisher organizations considered to manage resources successfully consistently presented high levels of linking social capital, irrespective of variability in bridging social capital. Using egocentric networks allows understanding actors' differences in the comanagement social structure, thus providing critical insights for improving comanagement systems. © 2012 by the author(s). Published here under license by the Resilience Alliance.


Abades S.R.,University of Santiago de Chile | Abades S.R.,University of Chile | Abades S.R.,Laboratorio Internacional en Cambio Global CSIC PUC | Marquet P.A.,University of Santiago de Chile | And 3 more authors.
Biological Research | Year: 2011

We analyzed the statistical distribution of intra-specific local abundances for a set North American breeding bird species. We constructed frequency plots for every species and found that they showed long-tail power-law behavior, truncated at an upper abundance cut-off value. Based on finite size scaling arguments, we investigated whether frequency curves may be considered scaled copies of each other. Data collapse was possible after taking powers of the total abundance of each species, in order to correct deviations from the underlying universal finite size scaling function (UFSS). The UFSS power law exponent oscillated in time within the regime of unbounded variance, which is consistent with the wild fluctuations that characterize ecological phenomena. We speculate that our results may eventually be linked to other law-like macroecological phenomena, such as energetic constraints reported in allometric scaling.

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