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Spatial sensitivity of species habitat patterns to scenarios of land use change (Switzerland) 总被引:3,自引:2,他引:3
Long-term societal trends which include decreasing population in structurally poorer regions and changes in agricultural policies
have been leading to land abandonment in various regions of Europe. One of the consequences of this development includes spontaneous
forest regeneration of formerly open-land habitats with likely significant effects on plant and animal diversity. We assess
potential effects of agricultural decline in Switzerland (41,000 km2) and potential impacts on the spatial distribution of seven open-land species (insects, reptile, birds) under land-use change
scenarios: (1) a business-as-usual scenario that extrapolates trends observed during the last 15 years into the future, (2)
a liberalisation scenario with limited regulation, and (3) a lowered agricultural production scenario fostering conservation.
All scenarios were developed in collaboration with socio-economists. Results show that spontaneous reforestation is potentially
minor in the lowlands since combinations of socio-economic (better accessibility), topographic (less steep slopes), and climatic
factors (longer growing seasons) favour agricultural use and make land abandonment less likely. Land abandonment, spontaneous
reforestation, and subsequent loss of open-land, however, are potentially pronounced in mountainous areas except where tourism
is a major source of income. Here, socio-economic and natural conditions for cultivation are more difficult, leading to higher
abandonment and thus reforestation likelihood. Evaluations for open-land species core habitats indicate pronounced spatial
segregation of expected landscape change. Habitat losses (up to 59%) are observed throughout the country, particularly at
high elevation sites in the Northern Alps. Habitat gains under the lowered agricultural production scenario range between
12 and 41% and are primarily observed for the Plateau and the Northern Alps. 相似文献
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175.
Alternative vaccination against equine botulism (BoNT/C) 总被引:1,自引:0,他引:1
Frey J Eberle S Stahl C Mazuet C Popoff M Schatzmann E Gerber V Dungu B Straub R 《Equine veterinary journal》2007,39(6):516-520
REASON FOR PERFORMING STUDY: In Europe the incidence of botulism in horses has increased in the last decade due to the growing popularity of haylage feeding. Recombinant vaccines are safer and less expensive to produce and are generally better tolerated than toxoids. OBJECTIVES: To investigate whether the recombinant C-terminal half of the heavy chain of the botulinum neurotoxin C (Hc BoNT/C) in combination with an immunstimulatory adjuvant is an appropriate vaccine candidate for horses by testing its efficacy to induce neutralising antibodies and by comparing its immunogenic properties and adverse reactions to a commercial toxoid vaccine. Formation of oedema and local pain reactions were assessed. ELISA and Western blot assay against Hc BoNT/C and testing of neutralising antibody induction in a mouse protection assay were used to evaluate the immune response. RESULTS: With the recombinant vaccine, only minor local swelling with full recovery after 5 days was noted after brisket injections. The toxoid vaccine produced local, painful reactions with longer recovery periods of up to 2 weeks. Horses vaccinated with either vaccine induced neutralising antibodies after the second booster vaccination, while seroconversion on ELISA and Western blot to Hc BoNT/C was apparent after the first recombinant vaccination, and at various time points in the vaccination schedule in horses that received commercial toxoid vaccine. CONCLUSION: The recombinant vaccine showed fewer adverse reactions compared to the only commercially available vaccine but induced similar concentrations of neutralising antibodies. There was no correlation between the serological response to Hc BoNT/C and the neutralising capacity of serum. POTENTIAL RELEVANCE: Recombinant Hc BoNT/C is an appropriate vaccine candidate to stimulate production of neutralising antibodies against botulinum neurotoxin C in horses and creates only minor local reactions at the injection site. 相似文献
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