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Jonsson M.,Swedish University of Agricultural Sciences | Bommarco R.,Swedish University of Agricultural Sciences | Ekbom B.,Swedish University of Agricultural Sciences | Smith H.G.,Lund University | And 4 more authors.
Methods in Ecology and Evolution | Year: 2014

Research relating to ecosystem services has increased, partly because of drastic declines in biodiversity in agricultural landscapes. However, the mechanistic linkages between land use, biodiversity and service provision are poorly understood and synthesized. This is particularly true for many ecosystem services provided by mobile organisms such as natural enemies to crop pests. These species are not only influenced by local land use but also by landscape composition at larger spatial scales. We present a conceptual ecological production function framework for predicting land-use impact on biological control of pests by natural enemies. We develop a novel, mechanistic landscape model for biological control of cereal aphids, explicitly accounting for the influence of landscape composition on natural enemies varying in mobility, feeding rates and other life history traits. Finally, we use the model to map biological control services across cereal fields in a Swedish agricultural region with varying landscape complexity. The model predicted that biological control would reduce crop damage by 45-70% and that the biological control effect would be higher in complex landscapes. In a validation with independent data, the model performed well and predicted a significant proportion of biological control variation in cereal fields. However, much variability remains to be explained, and we propose that the model could be improved by refining the mechanistic understanding of predator dynamics and accounting for variation in aphid colonization. We encourage scientists working with biological control to adopt the conceptual framework presented here and to develop production functions for other crop-pest systems. If this kind of ecological production function is combined with production functions for other services, the joint model will be a powerful tool for managing ecosystem services and planning for sustainable agriculture at the landscape scale. © 2013 British Ecological Society. Source

Mila C.C.,Natural History Museum of Barcelona
Mineralogical Record | Year: 2014

Panasqueira, an extensive complex of orebodies and mines, was discovered and worked for tin by the ancient Romans, and was opened to modern mining in 1885. Since then it has become famous as a source of superb specimens of green and purple fluorapatite, arsenopyrite, cassiterite, ferberite and other minerals, and is the type locality for panasqueiraite and thadeuite. The mines have been consistent suppliers of specimens for several decades and continue to yield fine minerals today. Source

Herrando S.,Catalan Ornithological Institute | Weiserbs A.,Aves Natagora | Quesada J.,Natural History Museum of Barcelona | Ferrer X.,University of Barcelona | Paquet J.-Y.,University of Barcelona
Animal Biodiversity and Conservation | Year: 2012

Bird monitoring projects have provided valuable data for developing biological indicators to evaluate the state of natural and agricultural habitats. However, fewer advances have been made in urban environments. In this study we used bird monitoring data from 2002 to 2012 in two cities with different climates (Brussels and Barcelona), to generate two multi-species urban indicators to evaluate temporal trends on abundance of urban avifauna. To do this we used two different conceptual approaches, one based on a list of widespread species in European cities (WSEC) and another based exclusively on species widespread at city level (WCS) regardless of the birds occurring in other cities. The two indicators gave a similar general pattern, although we found a 3% difference in the mean annual change in both cities, thus suggesting that the values provided by urban indicators may differ depending on the conceptual approach and, hence, by the species list used to generate them. However, both indicators may have their own value and could be treated as complementary indices. © 2012 Museu de Ciéncies Naturals de Barcelona. Source

Quevedo L.,CREAF | Arnan X.,CREAF | Arnan X.,TU Darmstadt | Boet O.,Natural History Museum of Barcelona | And 2 more authors.
Annals of Forest Science | Year: 2014

Context: In the Mediterranean area, different post-fire management strategies are used for coppices of resprouting species to promote a more regular forest structure, enhance plant growth, and reduce fire risk. However, the effects of these management treatments on forest-associated fauna are unknown, which in turn could be limiting their beneficial effects.Aims: The aim of this work was to determine whether forest management of a recently burned area dominated by a vigorous resprouting tree species (Arbutus unedo L.) affects ant communities.Methods: Ant communities, sampled using pitfall traps, were examined from unmanaged and selective thinning coppices of A. unedo. Ants are here used as bioindicators of ecosystem health and surrogates for other animal groups.Results: Very limited effects of these post-fire management strategies on the structure and composition of ant communities were found. The lack of effects could be due to the reported small changes in physical conditions among treatments; or either, the most sensitive ant species to these post-fire management treatments might be the same ones affected by fire and, consequently, the ant species that would potentially be affected most were no longer in the study area.Conclusion: The lack of any significant effects caused by these post-fire management practices on the associated fauna of A. unedo coppices points out the suitability of these treatments in these circumstances. © 2014, INRA and Springer-Verlag France. Source

Senar J.C.,Natural History Museum of Barcelona | Conroy M.J.,University of Georgia | Quesada J.,Natural History Museum of Barcelona | Mateos-Gonzalez F.,Uppsala University
Ecology and Evolution | Year: 2014

A standard approach to model how selection shapes phenotypic traits is the analysis of capture-recapture data relating trait variation to survival. Divergent selection, however, has never been analyzed by the capture-recapture approach. Most reported examples of differences between urban and nonurban animals reflect behavioral plasticity rather than divergent selection. The aim of this paper was to use a capture-recapture approach to test the hypothesis that divergent selection can also drive local adaptation in urban habitats. We focused on the size of the black breast stripe (i.e., tie width) of the great tit (Parus major), a sexual ornament used in mate choice. Urban great tits display smaller tie sizes than forest birds. Because tie size is mostly genetically determined, it could potentially respond to selection. We analyzed capture/recapture data of male great tits in Barcelona city (N = 171) and in a nearby (7 km) forest (N = 324) from 1992 to 2008 using MARK. When modelling recapture rate, we found it to be strongly influenced by tie width, so that both for urban and forest habitats, birds with smaller ties were more trap-shy and more cautious than their larger tied counterparts. When modelling survival, we found that survival prospects in forest great tits increased the larger their tie width (i.e., directional positive selection), but the reverse was found for urban birds, with individuals displaying smaller ties showing higher survival (i.e., directional negative selection). As melanin-based tie size seems to be related to personality, and both are heritable, results may be explained by cautious personalities being favored in urban environments. More importantly, our results show that divergent selection can be an important mechanism in local adaptation to urban habitats and that capture-recapture is a powerful tool to test it. © 2014 The Authors. Source

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