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21.
Mediterranean temporary ponds (MTPs) comprise an endangered habitat with several endemic species that can be found in many countries, mainly in the Mediterranean region but are disappearing at a high rate. For designing optimal conservation and management strategies for the particular ecosystems, appropriate characterization and classification of these ponds is necessary based on the different type of habitats and on their varying environmental conditions. This paper presents the current ecological status and the threats of Mediterranean temporary ponds and summarizes some management and conservation issues based on the existing experience on a regional level. Emphasis is given in the Greek MTPs with respect to their characteristics and the pressures received mainly from human activities such as agriculture and water overexploitation. Restoration practices should be commenced immediately aiming at the reestablishment of the ponds' hydroperiod and water quality at the natural levels.  相似文献   
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Manure can provide valuable nutrients, especially N, for grass forage, but high NH, volatilization losses from standard surface-broadcast application limits N availability and raises environmental concerns. Eight field trials were conducted to evaluate the emission of NH, from liquid dairy manure, either surface broadcast or applied in narrow surface bands with a trailing-foot implement. Manure was applied using both techniques at rates of approximately 25 and 50 m3 ha(-1) on either orchardgrass (Dactylis glomerata L.) on a well-drained silt loam or reed canarygrass (Phalaris arundinacea L.) on a somewhat poorly drained clay soil. Ammonia emission was measured with a dynamic chamber/equilibrium concentration technique. High NH3 emission rates in broadcast treatments, especially at the high rate (2 to 13 kg ha(-1) h(-1)), occurred during the first few hours after spreading, followed by a rapid reduction to low levels (<0.5 kg ha(-1) h(-1) in most cases) by 24 h after spreading and in subsequent days. Band treatments often followed the same pattern but with initial rates substantially lower and with a less dramatic decrease over time. Total estimated NH3 losses from broadcast application, as a percent of total ammoniacal N (TAN) applied, averaged 39% (range of 20 to 59%) from the high manure rate and 25% (range of 9 to 52%) from the low rate. Band spreading reduced total NH3 losses by an average of 52 and 29% for the high and low manure rates, respectively. Results show that the trailing-foot band application method can reduce NH3 losses and conserve N for perennial forage production.  相似文献   
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Electrical membrane potentials, oscillations, and action potentials are observed in proteinoid microspheres impaled with (3 M KCl) microelectrodes. Although effects are of greater magnitude when the vesicles contain glycerol and natural or synthetic lecithin, the results in the purely synthetic thermal protein structures are substantial, attaining 20 mV amplitude in some cases. The results add the property of electrical potential to the other known properties of proteinoid microspheres, in their role as models for protocells.  相似文献   
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Environmental Science and Pollution Research - This paper provides a novel survey of current collections of frozen raptor carcasses and tissue samples in natural history museums (NHMs),...  相似文献   
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This paper elaborates on the debate whether safety investigations are obsolete and should be replaced by more modern safety assessment approaches. Despite their past performance, in particular in aviation, accident investigations are criticized for their reactive nature and the lack of learning potential they provide. Although safety management systems are considered a modern method with a more prospective potential, they too are hard to judge by their quantitative performance. Instead of measuring both concepts along the lines of their output, this contribution explores the origin, context and notions behind both approaches. Both approaches prove to be adaptive to new developments and have the ability to shift their focus towards learning and cognition. In assessing their potential, accident investigations prove to cover a specific domain of application in the risk domain of low probability and major consequences, fulfilling a mission as public safety assessor. In order to make optimal use of their analytic and diagnostic potential, investigations should mobilize more complex and sophisticated scientific theories and notions, in particular of a non-linear nature. Consequently, they are neither reactive, nor proactive, but provide a specific approach to safety issues.  相似文献   
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Changes in land use and land cover are important in global climate change, but the many uncertainties in historical estimates seriously hamper climate modelling. We collected new data on estimated per capita land use over the last two millennia, using new data sources from the Humanities. In general, and in agreement with literature, we found that per capita land use indeed has not been constant in the past, but differ per region and over time. Land use in the distant past was mostly less than 1 ha/cap. However, the recently colonised regions show much higher values and have experienced a much higher per capita land use for the recent past. Most known trajectories follow a concave or bell-shaped curve towards the present.  相似文献   
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This review explores the social causes and psychological and organizational consequences of the criminalization of human error in aviation and healthcare. Increasing prevalence of criminal prosecution is seen as a threat to the health and safety of employees and entire safety–critical systems in many industries, but initiatives to counter or mitigate the trend are local and haphazard. Social causes such as a greater societal risk consciousness and intolerance of failure are examined, as well as organizational consequences for disclosure and incident reporting. Psychological consequences of the criminalization of human error are evaluated in terms of employee ill-health, an area that is under-investigated. The criminalization of professional mistakes seems to be an increasingly prevalent phenomenon at the intersection of safety work, sociology, criminology and legal as well as social justice. This paper reviews possible research directions into the criminalization of professional mistake in aviation and healthcare, in the hope of stimulating debate and eventually legitimating it as a topic of study in its own right.  相似文献   
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