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221.
222.
Blaž Kurnik Geertrui Louwagie Markus Erhard Andrej Ceglar Lučka Bogataj Kajfež 《Environmental Modeling and Assessment》2014,19(1):19-34
We compared soil moisture from the soil water balance model for European Water Accounting (swbEWA) with in situ observations from nine locations in three European climatic zones (continental, Mediterranean and maritime temperate), for different periods between 2003 and 2011. Despite the simplicity of the swbEWA model, the patterns of temporal changes in soil moisture content are well represented at all locations. Annual averages show that the model overestimates the soil moisture content, and that overestimations are the smallest when measurements are obtained from more than one depth. These results suggest that the relationship between simulated and observed soil moisture also depends on the number of measurements and the depth over which they are taken. In the continental climate, where snow cover and frozen soil influence soil moisture, we observe higher root mean square error values in winter months. However, in the Mediterranean and maritime temperate climates, we do not observe clear common seasonal patterns in the soil moisture profile, which makes it difficult to relate the model’s accuracy to climate. With the percentage of correctness and probability of detection measures, we tested the model performance in simulating dry versus non-dry events. The percentage of the correctly classified dry and non-dry events is higher than 84 % at all locations, whereas the probability to detect dry events is significantly lower, exceeding 50 % at only four out of nine stations. The frequency distribution of consecutive days with dry soil (CDDS) confirms the model performance: higher number of short dry periods (with less than 20 days of soil moisture near wilting point) are reproduced and observed in continental climates, whereas long dry periods (longer than 50 days) are noted in the Mediterranean climate. Overall, the statistical measures suggest that the model produces the highest accuracy in summer months at the stations in continental climates, whereas in the Mediterranean climate, the accuracy is slightly higher in the colder seasons. 相似文献
223.
Societal and technological development during the last century has enabled Western economies to achieve a high standard of living. Yet this profusion of wealth has led to several outcomes that are undesirable and/or unsustainable. There is thus an imperative need for a fundamental and rapid transition towards more sustainable practices. While broad conceptual frameworks for managing sustainability transitions have been suggested in prior literature, these need to be further developed to suit contexts in which the overall vision is arguably clear, such as in the case of consuming animal-originated foodstuffs. In this article we introduce a novel transition management framework that is based upon the dimensions of sustainability. The suggested transition management process includes the identification of objectives and obstacles, the listing of options and their opportunities and threats as well as the evaluation of the outcomes (the Five O’s). We argue that sustainability transition management should be a process in which the identification of the relevant dimensions of sustainability and related objectives forms the foundation for strategic, tactical and operational governance activities. We illustrate the practical applicability of the framework in the case of transition towards plant-based diets. 相似文献
224.
In Germany, plans at the local level to construct wind turbines often find support as well as rejection – often in both cases for ecological reasons. In this paper, we argue that the key to understanding local wind energy debates is to analyse the interrelations between collective identities and concepts of place. Based on the discourse theory of Laclau and Mouffe, we analyse how two completely contradictory place notions have evolved in a local dispute in a small town in Germany, and how existing political identities have been modified, realigned and superseded in the course of the conflict. Furthermore, we show how the involved discourses are characterised by strong continuities with respect to an earlier struggle over an asphalt mixing plant. 相似文献
225.
Ruuskanen S Helle S Ahola M Adamczyck F Möstl E Laaksonen T 《Behavioral ecology and sociobiology》2011,65(5):983-994
Early androgen exposure is known to have long-lasting effects on phenotype, behaviour and even fitness, but difficulties in
measuring the exposure hinders the study of its importance in evolutionary context. Digit ratios have been highlighted as
a potential easy-to-measure indicator of early steroid exposure, as they have been suggested to reflect steroid, mainly testosterone
levels during prenatal development. However, evidence for digit ratios reflecting early steroid levels is weak, as experimental
studies, especially in wild populations, are scarce. We studied the association between maternally derived yolk androgens
and digit ratios (2D:4D, 2D:3D and 3D:4D) using both correlative data and a rather high level of experimental elevation of
yolk androgens in a passerine bird, the pied flycatcher (Ficedula hypoleuca). We also examined whether digit ratios have indicator value in an evolutionary context by studying correlations between
digit ratios and reproductive traits, secondary sexual traits and exploratory behaviour. We did not find any association between
digit ratios and yolk androgen level either in correlative or experimental data. Digit ratios were neither related to any
of the reproductive and secondary sexual traits or exploratory behaviour measured. There was, however, a sex difference in
2D:3D and 3D:4D of adult birds (due to second and fourth digits being shorter in females), which was not apparent in fledglings
or captivity-raised juveniles. This suggests that either the sex difference may develop as late as during the sexual maturation
for breeding. These results indicate that, in this species, digit ratios are not reliable markers of maternally derived yolk
androgen exposure and that they bear little relevance as correlates of the adaptive traits we measured. 相似文献
226.
A new approach to investigate the interactions between sediment transport and ecotoxicological processes during flood events 总被引:1,自引:0,他引:1
Holger Schüttrumpf Markus Brinkmann Catrina Cofalla Roy M Frings Sabine U Gerbersdorf Markus Hecker Sebastian Hudjetz Ulrike Kammann Gottfried Lennartz Sebastian Roger Andreas Schäffer Henner Hollert 《Environmental Sciences Europe》2011,23(1):1-5
Purpose
The 'step-by step' principle was introduced into the European Union legislation on genetically modified organisms as a means to cope with uncertainty about environmental risks from the release of genetically modified organisms into the environment. The approval process is orientated along the stepwise reduction of containment which reflects a precautionary approach towards the risks of genetically modified organism release. Thus, the gradual reduction of containment should keep pace with the gradual generation of risk-related knowledge. This paper strives to clarify the meaning, legal status and practical importance of the principle. It also looks at whether non-European Union countries have adopted the principle as well, and how they practice it.Methods
The article is based on research of the relevant legal texts, court cases and legal literature. In addition, a number of dossiers of applications for the European Union authorisation of release and placing on the market of genetically modified seed were analysed.Results and conclusions
Although 'step-by-step' is not a precise legal rule it does have legal meaning as a principle guiding the risk assessment and management of genetically modified organism introduction into the environment. Assuming a process of gradual reduction of containment and scaling up of release ranging from closed systems via experimental release to cultivation the 'step-by-step principle' requires that the knowledge on environmental risks of genetically modified organisms should be generated on stages previous to the ones where the risk can result in damage. The analysis of the legislation of China, the United States of America and Brazil showed a differentiated approach towards the step-by-step principle. 相似文献227.
Andreas Dufke Thomas Eggermann Karl Oliver Kagan Markus Hoopmann Miriam Elbracht 《黑龙江环境通报》2023,43(8):983-992
Imprinting Disorders (ImpDis) are a group of congenital conditions caused by aberrant imprinting resulting in disturbed expression of parentally imprinted genes. ImpDis are rarely associated with major malformations, but pre- and/or postnatal growth and nutrition are often affected. In some ImpDis, behavioral, developmental, metabolic and neurological symptoms might present in the perinatal context or later in life, and in single ImpDis, there is a higher risk of tumors in childhood. Prognosis depends in part on the molecular cause of each ImpDis, but due to high clinical variability and (epi)genetic mosaicism, predicting the clinical outcome of a pregnancy solely based on the underlying molecular disturbance is difficult. Therefore, interdisciplinary care and treatment approaches play an important role in the management and decision making of affected pregnancies, especially taking into account fetal imaging in addition to genetic findings. Prenatal findings influence perinatal management, and thereby improve the prognosis of ImpDis associated with severe but sometimes transient clinical complications in the neonatal period. Therefore, prenatal diagnosis can be crucial for appropriate management not only to the pregnancy itself but might also have a life-long effect. 相似文献
228.
This paper contributes to the discussion on contingencies of process innovations by focusing on and introducing organizational‐level constructs of climate for initiative and psychological safety. We argue that process innovations, defined as deliberate and new organizational attempts to change production and service processes, need to be accompanied by climates that complement the adoption and implementation of such innovations. Our study of 47 mid‐sized German companies examines the relation between process innovations, climates for initiative and psychological safety, and firm performance. Results show that climates for initiative and psychological safety were positively related to two measures of firm performance—longitudinal change in return on assets (holding prior return on assets constant) and firm goal achievement—and moderated the relation between process innovations and firm performance. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
229.
Dagmar Laschka Thomas Striebel Joachim Daub Markus Nachtwey 《Environmental Sciences Europe》1996,8(3):124-129
Using platinum based catalytic converters, platinum is emitted with the exhaust gases and deposited on the roads, and in their vicinity (sewage treatment plants, rivers), which increases the platinum concentrations in aquatic eco-systems. To evaluate the platinum discharge from roads, the platinum concentration was measured in rainwater from a road with a traffic fre quency of 16,000 automobiles per day. The platinum content of the samples varies strongly dependent upon the previous dry period, and the intensity and duration of the rainfall. Platinum was measured in 18 run-off samples from various rainfall events. The maximum platinum concentrations showed values up to 1.1. μg/l. The median value was 15 ng/l. Analysis of a sample from one rainfall events shows that platinum has a well defined firstflush effect, similar to that of particular bound lead and copper. The good correlation between platinum and coarse suspended matter, coarse particular lead and copper indicates that platinum in road run-offs is frequently found to be particular bound. Under the assumption that the road has been completely washed off, the platinum deposition can be estimated to be 14 ng/(m2d). 相似文献
230.