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During the last 50 years, the Common Agricultural Policy (CAP) has impacted the evolution of European agricultural landscapes by driving changes in land use and farming practices. We propose a typology characterising the scales relevant for agricultural landscapes management and argue that action is required on three scales: (1) a landscape oriented management at the farm level; (2) the coordination of land managers’ actions at the landscape level; and (3) the conservation of the diversity of agricultural landscapes in the EU. We provide evidence that until now the CAP has mainly focused on the first scale. We also illustrate how agricultural policy could encourage coordinated actions at the landscape- and EU-scales. In particular, we propose policy instruments to coordinate actions of individual land owners (e.g. collective bonus in agro-environmental contracts or support to environmental cooperatives (scale 2)). We also analyse how the recognition and transposition of the European Landscape Convention could promote trans-frontier landscape cooperation in order, not only to conserve high-quality rural landscapes, but also to ensure the conservation of the diversity of EU landscapes (scale 3). This paper provides a knowledge base to support an integrated CAP design in the direction of improved landscape management, as an important component of the EU project towards more sustainable agriculture.  相似文献   
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During summer, a grizzly bear (Ursus arctos horribilis) in the Greater Yellowstone Ecosystem (GYE) (USA) can excavate and consume millions of army cutworm moths (Euxoa auxiliaris) (ACMs) that aggregate in high elevation talus. Grizzly bears in the GYE were listed as threatened by the US Fish and Wildlife Service in 1975 and were proposed for delisting in 2005. However, questions remain about key bear foods. For example, ACMs are agricultural pests and concern exists about whether they contain pesticides that could be toxic to bears. Consequently, we investigated whether ACMs contain and transport pesticides to bear foraging sites and, if so, whether these levels could be toxic to bears. In 1999 we collected and analyzed ACMs from six bear foraging sites. ACMs were screened for 32 pesticides with gas chromatography with electron capture detection (GC-ECD). Because gas chromatography with tandem mass spectrometry (GC-MS/MS) can be more sensitive than GC-ECD for certain pesticides, we revisited one site in 2001 and analyzed these ACMs with GC-MS/MS. ACMs contained trace or undetectable levels of pesticides in 1999 and 2001, respectively. Based on chemical levels in ACMs and numbers of ACMs a bear can consume, we calculated the potential of chemicals to reach physiological toxicity. These calculations indicate bears do not consume physiologically toxic levels of pesticides and allay concerns they are at risk from pesticides transported by ACMs. If chemical control of ACMs changes in the future, screening new ACM samples taken from bear foraging sites may be warranted.  相似文献   
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Donaldson FP  Nyman MC 《Chemosphere》2006,65(5):854-862
The fate of aromatic amines in natural systems is important to understand due to the persistence and toxicity of these chemicals. Laboratory experiments were performed to elucidate aniline and benzidine behavior in silty-clay, sandy loam, and sandy soils, and six background matrices (rainwater, 12.5 mM CaCl(2), 25 mM CaCl(2), and each passed through soil columns). The goals of this study were to test the validity of using CaCl(2) as a laboratory simulation for rainwater and to observe how short-term sorption (24 h) of aniline and benzidine changed when these solutions were passed through soil columns. Results indicated that neither CaCl(2) solution exactly predicted the sorption of these chemicals in corresponding rainwater solutions, likely due to varying soil properties that influenced the sorption mechanisms. Statistical analyses revealed that the passage of rainwater or CaCl(2) solutions through soil columns did not significantly affect the sorption of aniline or benzidine. Cation exchange and solubility plots were created to identify the sorption mechanisms taking place in the short-term batch experiments. These plots indicated that cation exchange played a role in the sorption of both aniline and benzidine under all conditions, while solubility plots showed higher correlations for benzidine, a consequence of its lower aqueous solubility.  相似文献   
97.
The aim of this work is to determine sediment properties, metal contents and transfers of Cd and Zn from dredged sediments to plants. To this end 10 deposit sites with different contexts were visited in France. The main agronomic characteristics and metal contents for surface soil layers were measured, the plant species present at the sites, such as Brassicaceae and Fabaceae, were listed, and the distribution of their root systems described. Soil characteristics such as available P (Olsen) varied between sites, with values ranging from 0.01 to 0.49 g kg(-1). Total contents and enrichment factors were studied, highlighting metal contamination in most of the sites. Despite carrying out principal component analyses, it was not possible to group deposits by age or geographical localisation. However, deposits could be distinguished as a function of proximity of industrial facilities, sediment grain size and carbonate content. Associations between metals were also highlighted: (1) Cd, Pb and Zn, and (2) Al, Cr, Cu and Fe. Consequently, we propose classifying them as technogenic anthrosols.  相似文献   
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Congenital CMV infection (cCMV) is the most prevalent congenital infection, main non-genetic cause of sensorineural hearing loss (SNHL) and major cause of neurological disability. Despite the burden of cCMV, no Public Health body recommends universal serology screening in pregnancy. This was explained by gaps in knowledge of epidemiology, diagnosis, prognosis and the absence of any validated treatment. Over 10 years, progress has been made in our understanding of cCMV following primary maternal infection. Risk factors have been identified and quantified, notably it is now well recognized that among maternal primary infections only those occurring in the first trimester may lead to long-term sequelae. Algorithms combining IgG, IgM, and IgG avidity detection with serological assays adapted on high throughput platforms have demonstrated high sensitivity and specificity to diagnose maternal primary infection. The prognostic value of prenatal imaging combining ultrasound and MRI has been validated by many studies. Finally, recent data from a randomized controlled study demonstrated the efficacy of early antiviral therapy to prevent vertical transmission. Whether CMV serology screening in the first trimester of pregnancy meets the WHO's criteria for a screening program will therefore be reviewed.  相似文献   
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