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Lena Gustafsson Mårten Berglind Anders Granström Achim Grelle Gunnar Isacsson Petter Kjellander 《Scandinavian Journal of Forest Research》2019,34(4):234-253
Deepened knowledge on response of biota and ecological processes following fire is essential for a future with warmer climate and more disturbances. In 2014 the first mega-fire (13,100 ha) for at least a century in Scandinavia hit south-central Sweden, in a production forest landscape shaped by clearcutting forestry. Ecological dynamics is followed in >20 projects from universities, authorities and citizen science initiatives, rapidly accumulating substantial amounts of data. We outline projects and summarize their results during the first four years, demonstrating a rapid succession of fungi, lichens, vascular plants, birds, mammals, ticks, butterflies, beetles, and drastically altered carbon dynamics. We characterize forest operations including regeneration measures and point to patterns in pest and pathogen infestations. 8,000 ha is set aside for natural succession, with the rest harvested and managed for forest production, offering excellent opportunities for studies on salvage logging effects, already evident for birds. We demonstrate a strong regrowth of deciduous trees, and the protected part will in some decades likely develop into the largest deciduous-dominated area in boreal north Europe outside Russia. Continued studies of biodiversity and ecological processes are urgent for this unique area. 相似文献
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Our aim was to compare the efficiency of different surveillance strategies for detecting scrapie-infected sheep flocks in the Norwegian population using simulation modelling.The dynamic Monte Carlo simulation model has the flock as the unit. The input parameters include properties of the sheep population (number of flocks, flock size, age distribution, reasons for culling, breeds, prion protein-allele distribution); properties of scrapie (genotype-dependent infection rate and incubation periods, and age- and genotype-dependent prevalence of scrapie); properties of the surveillance strategy (selection of sheep for examination, period in which infected sheep are detectable, and properties of the diagnostic tests). For simplification, the prion protein-alleles were grouped into three allele groups: VRQ, ARR, and ARQ' (ARQ' represents ARQ, ARH and AHQ).Through either abattoir surveillance or surveillance of fallen stock, 70% of the detected sheep (compared to 33% in the underlying population). The model output was sensitive to the susceptibility of infection for the genotype ARQ'/ARQ'. The effect was large for abattoir surveillance (increased susceptibility increased the efficiency of abattoir surveillance). 相似文献
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Hering-Hagenbeck SF Petter AJ Boomker J 《The Onderstepoort journal of veterinary research》2002,69(1):31-51
Thelandros schusteri Hering-Hagenbeck, 2001, Thelandros luciusi Hering-Hagenbeck, 2001, Thelandros boomkeri Hering-Hagenbeck, 2001, Tachygonetria bainae Hering-Hagenbeck, 2001, Tachygonetria chabaudi Hering-Hagenbeck, 2001 and Tachygonetria petterae Hering-Hagenbeck, 2001 from the plated lizard, Gerrhosaurus validus validus A. Smith 1849 from three localities in the north-eastern region of South Africa are redescribed. Classification keys are available only for the males of the species and because male and female nematodes in copula were not observed in this study as well as the similarity of the females, it was not possible to identify the females to the species level. Thelandros schusteri, Thelandros boomkeri and Thelandros luciusi were provisionally paired with female Type E, Tachygonetria bainae with female Type C, Tachygonetria chabaudi with female Type A and Tachygonetria petterae with female Type D. Female Types B and F could not be paired. The richness and composition of species of the Pharyngodonidae of Gerrhosaurus validus validus is close to that of tortoises and differs from the pharyngodonid fauna of the insectivorous lizards that have been studied. In the latter, only the genera Spauligodon, Skrjabinodon and Parapharyngodon were recovered. The pharyngodonid fauna of Gerrhosaurus validus validus seems to have originated by capture from local herbivorous reptiles. The three Tachygonetria spp. most closely resemble forms in South African tortoises. The three Thelandros spp. redescribed here not only show strong similarities to those of herbivorous Agama spp., but also to those parasitic in tortoises and could have been acquired from either. 相似文献
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The aim was to compare the protein release from normal human osteoblasts (NHO) cultured on scaffolds with similar morphology but different coatings. Different ceramic coatings; TiO(2), SiO(2) and calcium phosphate (CaP); Ca(9)HPO(4)(PO(4))(5)OH, were applied to porous TiO(2) scaffolds prepared by polymer sponge replication. NHO were cultured on scaffolds in triplicates. The concentration of cytokines and Ca(2+), and alkaline phosphatase (ALP) activity in the cell media was quantified. The secretion of osteopontin, osteoprotegerin, vascular endothelial growth factor and interleukin-6 was higher from NHO on TiO(2) compared to SiO(2) and CaP. The secretion from cells on the three scaffolds was, however, either similar or lower than the control cells cultured on plastic. The Ca(2+) concentration was higher in cell media on CaP the first week, and no difference in ALP activity was observed. TiO(2) coating induced a higher secretion of factors indicating enhanced osteoblast differentiation as compared to CaP and SiO(2). 相似文献
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The EU project ‘DROPSA’ started in 2014 and aims to improve plant health strategies in the fruit sector. The project is being conducted by an international consortium of 26 partners consisting of phytosanitary organizations, companies, research institutes and universities and will last 50 months. Results will be disseminated via conventional publications and will be brought together in the development of risk‐based strategies to prevent the introduction of new fruit pests. This article describes the task related to the preparation of alert lists of pests that may be introduced into Europe with the trade of fruit. Activities of this task include the investigation of pathways of introduction for fruit pests into Europe, the development of alert lists for selected fruit crops and a review of current legislation. A review of introductions, interceptions and outbreaks that occurred during the last 10–15 years was conducted and is summarized, showing the relevance of fruit trade for the international movement of pests. Work has started on the development of alert lists for selected pathways. In this context, important fruit crops (including Malus, Vaccinium, Vitis, Citrus) were selected. 相似文献
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Tomato fruit are currently imported from different parts of the world to the EPPO region, and tomato is an important crop throughout the EPPO region both as an outdoor and indoor crop. The risk that tomato fruit may act as a pathway of introduction of new pests was identified after the introduction of Tuta absoluta in the EPPO region in 2006. A study was launched in 2013, to produce a list of pests associated with the pathway of fruit of Solanum lycopersicum (tomato). The objectives, process and first outcomes of the study are presented here. One main outcome of the study is the recommendation of a general phytosanitary import requirement for a phytosanitary certificate for tomato fruit, thereby ensuring that tomato fruit are inspected at export. 相似文献
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Oscar Nordahl Per Koch-Schmidt Petter Tibblin Anders Forsman Per Larsson 《Ecology of Freshwater Fish》2020,29(1):18-30
Knowledge of patterns and drivers of the spatiotemporal distribution of top predatory fish is key to understand ecological dynamics and to successful management. Here, we integrated field and laboratory approaches to study vertical movements of pike (Esox lucius) in relation to season, light regimes and body temperature. We tagged pike from the Baltic Sea with data storage tags during spawning migration and retrieved them during migration the following years to obtain high-resolution data from full year of movements. The results showed seasonal and diel patterns of activity and body temperature that conformed to distinct patterns of crepuscular activity and diel vertical migrations. The latter manifested as two different patterns, either a stationary phase in the surface water during day followed by night-time in deeper water or vice versa. The occurrence of these two behaviours varied among individuals and within individuals among seasons. Diel vertical migration has previously not been described for this shallow-dwelling species, but was a common and consistent behaviour among individuals in this study. We suggest that the function of the daytime surface behaviour in pike is to increase body temperature through sun basking. This thermoregulatory role of surfacing was supported by the laboratory study where individuals sought the surface layer, exposed themselves to infrared light and thereby attained body temperatures in excess of ambient water. These results support sun basking as a mechanism for heat gain and further suggest that access to sunlight in the surface layer could be an important driver of vertical migrations. 相似文献
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The EPPO Secretariat has developed computer software for Pest Risk Analysis (PRA) within the EC 7th Framework Programme PRATIQUE (Enhancements of Pest Risk Analysis Techniques) and with the support of the EPPO Panels. The software, Computer Assisted PRA (CAPRA), aims to assist pest risk analysts to run the EPPO Decision‐support scheme for pest risk analysis [EPPO Standard PM 5/3(5) Decision‐support scheme for quarantine pests], and other decision‐support schemes. It is freely avaliable on the EPPO website or on http://capra.eppo.org/ . 相似文献