6 research outputs found

    La conservación de los insectos en España, una cuestión no resuelta

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    Los insectos, el grupo de organismos vivos con la más alta biodiversidad conocida, agrupa el 55% de todas las especies descritas y se encuentran en todos los ecosistemas terrestres y de agua dulce donde ocupan una gran variedad de nichos, participando en todos los procesos ecológicos. Este grupo de animales presenta una alta diversidad de hábitos tróficos, pudiendo ser fitófagos, saprófagos, descomponedores, depredadores o parasitoides, siendo los principales responsables del reciclaje de más del 20% de la biomasa vegetal terrestre (Samways, 1994, 2005), y uno de los principales degradadores de restos de origen animal (Galante & Marcos-García, 2004a). Por otra parte, los insectos son imprescindibles como mantenedores y generadores de biodiversidad vegetal ya que más del 75% de las plantas con flores de todo el mundo dependen de la acción polinizadora de los insectos (Tepedino & Griwold, 1990; Fontaine et al., 2006)

    Los escarabajos coprófagos (Coleoptera: Scarabaeoidea) en el parque nacional de Cabañeros: influencia del hábitat y el paisaje

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    Protected areas play an essential role in biodiversity conservation reflecting in some manner the environmental conditions that allow both the existence of communities with high species richness and the maintenance of ecological processes. We presented the main findings of a study of landscape structure and its influence on the biodiversity patterns of dung beetles in the Cabañeros National Park. Using pitfall traps in three habitat types immersed in three different landscape matrices (forest, scrubland and grassland) we recorded 75000 individuals of 52 species of dung beetles. Differences found in species richness and composition at habitat and landscape scales support the idea that the conservation of biodiversity in Mediterranean ecosystems implies the maintenance of the natural levels of spatial and temporal heterogeneity at all scales.Este trabajo se hizo posible gracias a diversos proyectos de estudio de la biodiversidad entomológica del Parque Nacional de Cabañeros: Ministerio de Medio Ambiente (040/2002), Ministerio de Educación y Ciencia (CGL2005-07213/BOS y CGL2008-03878) y Consellería de Empresa, Universidad y Ciencia Generalitat Valenciana GV05/096

    Extinction trends of threatened invertebrates in peninsular Spain

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    Using information from two recently published atlases of threatened invertebrate species in peninsular Spain, we examined the climatic, land use and geographic characteristics of the 100 km2 UTM cells with most likelihood of suffering extinctions (extinction cells), as well as the attributes of the species prone to population extinctions. Extinction cells have had significantly (1) lower precipitation values, (2) higher temperatures, (3) higher percentages of anthropic land uses or (4) higher rates of anthropization during the last 20 years than the remaining cells. Nevertheless, probable extinctions may occur under a wide range of climatic and anthropization change rates and these variables can only explain a low proportion (~5 %) of variability in the occurrence or number of extinction cells. Aquatic species seem to suffer higher local extinction rates than terrestrial species. Interestingly, many invertebrate species with approximately 25 or less occurrence cells are on a clear trajectory towards extinction. These results outline the difficulties and uncertainties in relating probable population extinctions with climatic and land use changes in the case of invertebrate data. However, they also suggest that a third of the considered Spanish threatened species could have lost some of their populations, and that current conservation efforts are insufficient to reverse this tendency.This work was supported by project Atlas of the Threatened Invertebrates of Spain Ministerio de Medio Ambiente y Medio Rural y Marino

    Ivermectin residues disrupt dung beetle diversity, soil properties and ecosystem functioning: An interdisciplinary field study

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    Ivermectin is the most common endectocide used to control parasites affecting livestock. Short-term physiological and behavioural effects of ivermectin on dung beetles may have long-term consequences for beetle populations and ecosystem functioning. Long-term effects of the use of ivermectin can be estimated by comparing dung assemblages and ecosystem functions in areas with conventional ivermectin-treated livestock and environmentally similar areas in which livestock are not treated with veterinary medical products (organic farming). In this study, we investigated both short-term and long-term effects of the administration of ivermectin on the characteristics of dung beetle assemblages and the services they provided in a protected area (Doñana National Park, SW Spain). We examined short-term dung colonization, dwelling, relocation, and disaggregation rates and the associations between these processes and the key assemblage parameters of species richness, abundance, biomass and functional diversity. Furthermore, we analysed changes in soil physical-chemical properties and processes. Short-term differences were observed in the total amount of dung relocated by dung beetles at different colonization vs. emigration stages, suggesting that dung beetles in this area were affected by the recent treatments of livestock with ivermectin. Moreover, short-term effects could also be responsible for the significant differences in dung spreading rates between sites. Conventional use of ivermectin disrupted ecosystem functioning by affecting species richness, abundance and biomass. The decrease in diversity parameters was related to a reduction in the functional efficiency, which resulted in the long-term accumulation of dung on the ground and considerable changes in soil functionality.Financial support was provided by the projects CGL2015-68207-R of the Secretaría de Estado de Investigación–Ministerio de Economía y Competitividad, and OAPN 762/2012 of the Organismo Autónomo de Parques Nacionales-Ministerio de Agricultura, Alimentación y Medio Ambiente
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