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[en] The Norwegian University of Life Sciences (NMBU) started global radiation (G) measurements in 1949. PAR measurements started in 1978 as part of a Nordic project. The project terminated in 1981, but the measurements continued at NMBU. We have used the data from the Nordic project’s seven stations and the long time series from NMBU to investigate the limitations of using the relative flux density method for the estimation of PAR from G. The yearly mean value of the relative flux density PAR/G at NMBU is 0.48 with a standard deviation of 0.02. The monthly mean values of PAR/G show a seasonal variation, with its maximum (0.50) in late summer and minimum in the winter months (0.45). The seasonal variation corresponds to 15% difference in relative cloud cover. Data from the original Nordic project gave the opportunity to investigate the usability of the relative flux density method in the Nordic area. The flux ratio for July was generally larger than the ratio for September or October, even though the differences are small and not statistically significant. In trying to explain this, one obvious candidate is the cloud cover. In the lack of cloud data, time records of global radiation were used to select fair weather and overcast days. For all stations, fair days show higher flux ratios and overcast days show lower flux ratios. Neglect of cloud cover may lead to an error in the calculation of PAR from the simple formula PAR = constant G of the order of 10%.
[en] In the annual report 1996 of the Federal Ministry of Research and Technology, the points of emphasis of the ecological research programme and their financing are discussed. The individual projects in the following subject areas are described in detail: urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, other ecosystems and landscapes, terrestrial ecosystem research, environmental pollution and human health and cross-sectional activities in ecological research. (vhe)
[de]Im vorliegenden Jahresbericht 1996 des Bundesministeriums fuer Forschung und Technologie werden die Programmschwerpunkte des Bereiches Oekologische Forschung und deren Finanzierung erlaeutert. Die einzelnen Projekte zu den Themenschwerpunkten urban-industrielle Landschaften, Waelder, Agrarlandschaften, Fluss- und Seenlandschaften, weitere Oekosysteme und Landschaften, terrestrische Oekosystemforschung, Umweltbelastung und Gesundheit des Menschen sowie die Querschnittsaktivitaeten der oekologischen Forschung werden ausfuehrlich dargestellt. (vhe)
[en] This document reflects the current practice for design of MSE walls using Partial coefficients. A deep compassion between three of the most applied methodologies around the world for the design of this type of structures has been done (Galindo, 2012). In the study, almost all the limit states involved in an external and internal analysis were analyzed. The methodologies under study are the FHWA NHI-10-024 (2009), BS-8006 ((2010) and EBGEO (2010) used in United States, Great Britain and Germany, respectively. Like a complement of the analysis, the results of two examples developed with the three methodologies are presented, showing that exist a tendency to a more conservative wall design for EBGEO and BS 8006 in comparison with FHWA. (Author)
[en] Although intensive marine fish farming is often assumed to be eco-friendly, the associated activity can lead to chronic exposure of marine organisms to potentially toxic discharges. Moreover, despite the increasing popularity of integrated multi-trophic aquaculture (IMTA), studies of the effects of fish farm effluents are almost non-existent. In the present study, the changes in the toxic potential of effluents from five land-based marine fish farms in NW Spain subjected for different lengths of time to a biodegradation procedure (for 0, 48, 120, and 240 h) were assessed in a battery of bioassays including organisms from different trophic levels (Vibrio fischeri, Isochrysis galbana, and Paracentrotus lividus). The results of the bioassays at the different times were then considered together with farm water flow in the Potential Ecotoxic Effects Probe (PEEP) index. Despite the high volumes of effluents discharged, the generally low toxicity of the effluents hinders assessment of potentially toxic effects. However, dose–response curves and statistical analysis demonstrated the existence of toxic effects during the first five days of the biodegradation procedure, especially immediately after sampling. The proposed modification of the PEEP index better reflects the changes in toxicity over time. .
[en] This paper describes the status of research in transportation sector with particular attention on reduction of energy consumption and pollutant emission
[it]In questo lavoro si descrivono i possibili contributi alla riduzione dei consumi e delle emissioni che possono derivare da miglioramenti tecnologici di veicoli, propulsori, carburanti e sistemi di controllo
[en] Complete text of publication follows. In 2008, we acquired long period electromagnetic data with a high data quality up to periods of 100.000 seconds along a profile running across the Leinegraben near Goettingen to the western Eifel, crossing the Rhenish massif. The Eifel as well as the region around Goettingen saw at different times intercrustal volcanic activity. Previous studies found big, highly conductive crustal anomalies located under the Eifel and near Goettingen. Between those anomalies, the conductivity of the mantle is raised in the east-west direction. Our data are complementing a large data set that is giving good spatial coverage of the area. Using geomagnetic depth sounding, we aim to improve the understanding of the structure of the crustal conductivity anomalies on both ends of the profile and will investigate their relationship with the upper mantle anisotropy in the area. One hypothesis is that the anomalies could have been produced by a single mantle plume.
[en] This analysis of the frequency, intensity, and duration of thermal inversions is based on daily minimum (tn) and maximum (tx) temperatures recorded over 3 years at 16 pairs of data loggers located under forest cover in the Jura Mountains of France. Each pair consists of a logger located at the bottom of a depression and another located higher up either nearby (local site) or more than 40 km away (regional site). The daily frequency of inversions is maximum at local sites for tn (50%) and minimum for tx at regional sites (4%). The maximum intensity of the inversions reaches 15.1 °C for tn and 16.2 °C for tx. The average intensity is about 2 °C: 1.5 °C for tx at local sites and 2.4 °C at regional sites. The duration of inversions is generally short: 60% of them last less than a day. Of the inversions that last for more than 1 day, 15% exceed 3 days and the maximum duration observed is 22 days. The relationship between the diurnal amplitude of temperature and the frequency, intensity, and duration of inversions indicates that mesoscale atmospheric conditions directly influence inversions.