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Sobre races i etnologia animal a Catalunya, Sobre razas y etnología animal en Cataluña, On animal breeds and ethnology in Catalonia

  • Parés Casanova, Pere-Miquel
This paper makes a review of the key moments in the study of Catalan local breeds, shedding light on the bias that most previous studies have shown by being more ethnographic than ethnological in character, if 'ethnography' is understood to be 'descriptive ethnology'. In other words, they have often failed to reach the level of ethnological analyses, being merely external observations. We also expose some clichés that pivot around the concept of breed, highlighting the importance of going beyond the consideration of breeds as mere repositories of a genetic pool., En aquest article, l’autor fa un repàs del que considera que són els grans moments en l’estudi de les races autòctones catalanes, i hi destaca que la majoria han estat estudis més de caire etnogràfic que etnològic, si entenem l’etnografia com una «etnologia descriptiva», i sovint no s’ha superat el primer pas per a l’anàlisi etnològica, que ultrapassa la simple observació externa. A més, s’hi exposen alguns tòpics que planen sobre el concepte de raça, i l’autor destaca la importància d’anar més enllà de considerar-les com a mers dipositaris d’un patrimoni gènic., En este artículo, el autor repasa lo que, según su parecer, son los grandes momentos en el estudio de las razas autóctonas de Cataluña. A la vez, destaca el sesgo del que han adolecido la mayoría de esos estudios, en el sentido de constituirse más como meramente etnográficos que etnológicos —bajo el prisma de que la etnografía constituiría una «etnología descriptiva»—; o, dicho de otro modo, que frecuentemente estos estudios no han superado la simple observación externa, sin tener en cuenta los valores y elementos antrópicos que las envuelven. El autor expone, además, algunos tópicos que pesan sobre el concepto de raza, destacando lo importante que es ir más allá de su consideración como un mero depositario de un acervo génico y tener en cuenta todo el acervo cultural que lleva asociado.
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Cuticular wax composition of ʻCelesteʼ and ʻSomersetʼ cherry fruit

  • Belge, Burcu
  • Comabella, Eva
  • Graell i Sarle, Jordi
  • Gatius Cortiella, Ferran
  • Guillén, Pere
  • Llovera i Arcas, Montserrat
  • Lara Ayala, Isabel
The cuticular layer plays an important role in protecting fruits against water loss and invasive microorganisms and insects, both during on-tree development and postharvest storage. There is also experimental evidence that cuticle composition and structure may be a relevant factor accounting for firmness and other textural attributes. Waxes are important cuticle components, together with the polymer matrices cutin and cutan. In this work, the chemical composition of waxes in the skin of 'Celeste' and 'Somerset' cherry (Prunus avium L.) fruit, which display quite different firmness levels, was investigated by means of gas chromatography-mass spectrometry (GC-MS). Fruit were picked at commercial maturity, and cuticles isolated enzimatically at harvest and after 3 days at 20°C. Total waxes were identified and quantified by means of GC-MS and GC-FID, respectively. In all cases, the most abundant constituent of cuticular waxes was the triterpene ursolic acid, which accounted for 49-56% ('Celeste') and 47% ('Somerset') of total wax composition. Important amounts of the alkanes nonacosane (6-10%, depending on cultivar and days at 20°C) and heptacosane (1-2%), as well as of the fatty acid linoleic acid (5-10%), were also found. Total alkane content was higher in 'Somerset' than in 'Celeste', but in contrast 'Celeste' cuticles were richer in triterpenes and fatty acids than those isolated from 'Somerset', thus showing some cultivar-related differences in the chemical composition of cuticular waxes., B. Belge is the recipient of a FI-DGR grant from AGAUR (Generalitat de Catalunya). This work was funded through the AGL2010-14801/ALI project, granted by the Ministerio de Ciencia e Innovación (MICINN) of Spain.
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Cell wall metabolism in cold-stored 'Somerset' sweet cherry fruit

  • Belge, Burcu
  • Comabella, Eva
  • Graell i Sarle, Jordi
  • Gatius Cortiella, Ferran
  • Guillén, Pere
  • Llovera i Arcas, Montserrat
  • Lara Ayala, Isabel
'Somerset' is a dark-red, sweet cherry (Prunus avium L.) cultivar displaying remarkable firmness levels, with concomitantly longer shelf-life potential in comparison to other varieties. It is generally accepted that fruit firmness depends mainly on the composition, structure and interconnections among cell wall polysaccharides. However, the biochemical mechanisms involved in cell wall disassembly vary widely among species, and the understanding of the processes underlying firmness loss in cherry fruit is particularly poor, although a critical role for β-galactosidase (β-Gal) activity has been suggested. In this study, 'Somerset' fruit were hand-collected at commercial maturity, and kept at 0 ºC for 14 or 28 days plus 3 additional days at 20 ºC to simulate commercial shelf life. Firmness, weight loss and juiciness were assessed in each case as indicators of fruit texture. Soluble and insoluble cell wall materials were extracted from lyophilized tissue, and a number of cell wall-modifying enzyme activities were also assessed therein. While β-xylosidase (β-Xyl), α-L-arabinofuranosidase (AFase) and pectin methylesterase (PME) activities were apparently connected to ripening-related firmness changes in this cherry cultivar, data obtained do not support a role for β-Gal in this process., B. Belge is the recipient of a FI-DGR grant from AGAUR (Generalitat de Catalunya). This work was funded through the AGL2010-14801/ALI project, granted by the Ministerio de Ciencia e Innovación (MICINN) of Spain.
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Destination image analytics through traveller-generated content

  • Mariné Roig, Estela
The explosion of content generated by users, in parallel with the spectacular growth of social media and the proliferation of mobile devices, is causing a paradigm shift in research. Surveys or interviews are no longer necessary to obtain users' opinions, because researchers can get this information freely on social media. In the field of tourism, online travel reviews (OTRs) hosted on travel-related websites stand out. The objective of this article is to demonstrate the usefulness of OTRs to analyse the image of a tourist destination. For this, a theoretical and methodological framework is defined, as well as metrics that allow for measuring different aspects (designative, appraisive and prescriptive) of the tourist image. The model is applied to the region of Attica (Greece) through a random sample of 300,000 TripAdvisor OTRs about attractions, activities, restaurants and hotels written in English between 2013 and 2018. The results show trends, preferences, assessments, and opinions from the demand side, which can be useful for destination managers in optimising the distribution of available resources and promoting sustainability.
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Does total antioxidant capacity play a central role in postharvest deterioration of 'Sweetheart' sweet cherry fruit?

  • Comabella, Eva
  • Belge, Burcu
  • Lara Ayala, Isabel
'Sweetheart' cherries (Prunus avium L.) have sweet flavour, bright red colour and a distinctive heart shape which contributes to their wide commercial acceptance. They display also comparatively high firmness and long shelf-life potential. Enzyme-catalysed disassembly of cell walls has been generally targeted as the main factor accounting for ripening-related changes in fruit firmness and overall texture, but the biochemical mechanisms involved in this process appear to include additional factors such as oxidative scission of cell wall polysaccharides. In this study, 'Sweetheart' fruit were hand-collected at commercial maturity, and kept at 0 ºC for 15 or 30 days plus 3 days at 20 ºC to mimic their retail period. Firmness, weight loss and juiciness, together with the incidence of decay and stem browning, were chosen as indicators of commercial quality of fruit. Cell wall materials were extracted and fractionated, related enzyme activities were assessed, and ascorbic acid content as well as radical scavenging activity (RSA) were also determined. Fruit displaying higher RSA showed higher values for firmness and lower weight loss, decay and stem browning incidence. Higher firmness levels were associated to higher RSA and to yields of the cell wall fractions enriched in convalently-bound pectins and hemicelluloses. β-galactosidase, pectinmethylesterase and endo-1,4-β-D-glucanase activities correlated inversely to firmness, while pectate lyase activity appeared to be relevant for solubilisation of cell wall materials and was inversely related to ascorbic acid content., B. Belge is the recipient of a FI-DGR grant from AGAUR (Generalitat de Catalunya). This work was funded through the AGL2010-14801/ALI project, granted by the Ministerio de Ciencia e Innovación (MICINN) of Spain.
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Effects of livestock management on carbon stocks and fluxes in grassland ecosystems in the Pyrenees

  • Casals, Pere
  • Garcia-Pausas, Jordi
  • Romanyà i Socoró, Joan
  • Sanz, Maria J.
  • Camarero, Lluís
  • Sebastià, Ma. T.
Grassland ecosystems can constitute a source or a sink in the global C balance, and their management affect their position in that balance. We aim to assess soil organic carbon (SOC) content and determine how grazing affects C fluxes and stocks in grasslands at high altitude in the Pyrenees. In a preliminary survey we found that total SOC ranges from 65 to 300 Mg ha-1 in these ecosystems, and is partially explained by complex combinations of variables representing topography, macroclimate and bedrock. In a second, more detailed survey, we improved the modelling of SOC by introducing management variables and standing biomass. Preliminary results of this work suggested that abandoned areas had lower SOC than grazed areas, and the higher SOC contents occurred when both sheep and cattle grazed in the area. The importance of management in soil carbon accumulation was confirmed in an experiment developed in two subalpine locations, where we found a sharp increase in active soil organic matter in grazed compared to non-grazed plots. The Eddy covariance method showed that an intensely grazed area was a slight sink for C, in spite of the elevated C efflux in August, when temperatures were very high and vegetation had been heavily grazed., R. Rodríguez, M. Guardiola, N. Serena, P. Ferrer and others provided much help with sampling and in the lab. This study was funded by the project CARBOPAS, from the Spanish Ministry of Science and Technology; the Vth Framework Projects EMERGE and CARBOMONT; and INTERREG III-A. The Fundació Territori i Paisatge and the Natural Park Cadí-Moixeró offered much support in the development of the projects.
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Changes in biodiversity composition and soil nutrient content with management in a Pyrenean grassland community

  • Ribas Artola, Àngela
  • Llurba, Rosa
  • Ventura, D.
  • Hodge, Angela
  • Sebastià, Ma. T.
We investigated the influence of livestock type on vegetation and biogeochemical cycling in grasslands with the objective of describing differences between agropastoral systems experiencing different managements from a trophic perspective. We sampled grassland plots in the Pyrenees of which four were grazed by sheep and four by cattle. We defined three patch types, based on the specific and functional plant composition: Legume-dominated (mostly by Lotus corniculatus); Grass-dominated (mainly by either Festuca nigrescens or Nardus stricta); and Forb-diverse (with Myosotis sylvatica and a diversity of other species). We sampled both above- and below-ground to obtain information about vegetation, roots (including mycorrhiza colonization) and soil nutrients. The above- and belowground plant biomass depended upon functional components of the patch and on grazing management. Plant allocation to green and dead matter changed between management types. Further, differences in grassland vegetation composition between cattle- and sheep-grazed areas found in previous studies were also confirmed. Higher P and NO3 concentrations in cattle-grazed areas suggest eutrophication under this management, linked with lower mycorrhizal colonisation. Our results therefore confirm patterns in previous studies and provide a deeper insight into the mechanisms of biotic differentiation and biogeochemical processes associated with differences in grazing management., This work was supported by the CARBOAGROPAS (CGL2006-13555-C03-01/BOS) and the OBAMA (CGL2009-13425-C02-01 /BOS) projects from the Spanish Ministry of Education and Science, and Consolider-Ingenio Montes SD2008-00040.
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Diversity-ecosystem function relationship in mixed forage crops

  • Llurba, Rosa
  • Ribas Artola, Àngela
  • Ventura, D.
  • Connolly, John
  • Sebastià, Ma. T.
Monocultures and three species mixtures containing a grass (Festuca arundinacea), a legume (Medicago sativa) and a forb (Cichorium intybus) were sown in order to test the effects of diversity on forage swards. Yield, LAI (Leaf Area Index), leaching and stability indicators were determined as a function of sown species identity and diversity effects. Yield and LAI were higher in mixed swards than in monocultures. A diversity effect was found for both variables, with values in mixtures above that expected from the proportions of the sown species. There was a seasonal substitution of species dominance, thus maintaining overall total yield. As a result, mixtures showed higher stability than monocultures. On the other hand, we found a negative effect of total biomass on leaching, but this trend was not consistent across the 6 studied harvests., We thank Faustina, Teri, Laura, Josep and all the helpful hands that have made that project possible. This research project was supported by the Spanish Ministerio de Medio Ambiente.
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Multi-species mixtures - new perspectives on models and mechanisms

  • Connolly, John
  • Bell, Thomas
  • Brophy, Caroline
  • Carnus, Timothee
  • Finn, John A.
  • Kirwan, Laura
  • Lüscher, Andreas
  • Sebastià, Ma. T.
  • Weigelt, Alexandra
The delivery of essential ecosystem functions (primary productivity, maintenance of soil fertility, resistance to weed invasion etc.) may be compromised by global declines in biodiversity. There is still controversy about the description of, and mechanisms behind, Biodiversity-Ecosystem Function (BEF) relationships. The Diversity-Interactions model quantified BEF relationships in terms of all the pairwise interactions between the species in a community. The model gives the contribution of two species (i and j) to the functional response in a community as _ijPiPj, where _ij reflects the potential of the two species to contribute to the response and its actual contribution depends also on Pi and Pj, the initial relative abundance of the two species in the community. This model and variants fitted well to a wide range of functional responses (biomass production, respiration) from several, but not all, experiments that examined a wide range of organisms (plants, microorganisms) and levels of species richness (1 to 72 species). A modified version introduces a more complex effect of pairwise interaction. The properties of this more flexible model and its implications for BEF relationships are discussed, particularly in the context of grass-clover contributions to sward functions.
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Every tree is a large subtree of a tree that decomposes Kn or Kn,n

  • Lladó, A.
  • López Masip, Susana-Clara
  • Moragas, J.
Let T be a tree with m edges. A well-known conjecture of Ringel states that every tree T with m edges decomposes the complete graph K2m+1. Graham and H¨aggkvist conjectured that T also decomposes the complete bipartite graph Km,m. In this paper, we show that there exists an integer n with n  d3(m 1)/2e and a tree T1 with n edges such that T1 decomposes K2n+1 and contains T. We also show that there exists an integer n0 with n0 2m 1 and a tree T2 with n0 edges such that T2 decomposes Kn0,n0 . In the latter case, we can improve the bound if there exists a prime p such that d3m/2e  p  2m 1., This work was supported by the Ministry of Science and Education of Spain under project MTM2005-08990-C02-01 and by the Catalan Research Council under grant 2005SGR00256.
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