Investigation on age and genesis of silcretes in Queensland (Australia)–Preliminary results     

Ulrich Radtke  Helmut Brüuckner 《地球表面变化过程与地形》1991,16(6):547-554

Silcretes from Queensland (Australia) were dated by means of the electron spin resonance dating technique. The results range from 1.5 to 10.8 million years; therefore, these silcretes were formed between the upper Miocene and the early Pleistocene. For a conclusive interpretation of the data geochemical and thin section analyses were also carried out. ESR dating of silcretes for the first time offers a direct approach to a chronostratigraphic framework of the genesis of these duricrusts, and of the palaeoclimatic events attributed to them.  相似文献   

Cyclogenesis induced by the Alps     

H. Pichler  R. Steinacker  A. Lanzinger 《Meteorology and Atmospheric Physics》1990,43(1-4):21-29

Summary Two different kinds of orographically induced cyclogenesis in the Western Mediterranean are being found to occur. The first takes place below a southewesterly, the second below a north to northwesterly upperlevel flow. Examples of both kinds are discussed from the standpoint of vorticity dynamics-separating shear and curvature-by means of fine mesh analyses in the Alpine region. Differences and similarities of both types are being discussed where as a new result it was found that divergence is well correlated with the conversion rate from shear into curvature vorticity.With 6 Figures  相似文献   

Reservoirs as sentinels of catchments: the Rappbode Reservoir Observatory (Harz Mountains, Germany)   总被引：2，自引：2，他引：0  

Karsten Rinke  Burkhard Kuehn  Serghei Bocaniov  Katrin Wendt-Potthoff  Olaf Büttner  Jörg Tittel  Martin Schultze  Peter Herzsprung  Helmut Rönicke  Karsten Rink  Kristine Rinke  Maren Dietze  Marco Matthes  Lothar Paul  Kurt Friese 《Environmental Earth Sciences》2013,69(2):523-536

Reservoirs can be viewed as sentinels of their catchments and a detailed monitoring of reservoir systems informs about biogeochemical and hydrological processes at the catchment scale. We developed a comprehensive online monitoring system at Rappbode reservoir, the largest drinking water reservoir in Germany, and its inflows. The Rappbode Reservoir Observatory comprises of a set of online-sensors for the measurement of physical, chemical, and biological variables and is complemented by a biweekly limnological sampling schedule. Measurement stations are deployed at the four major inflows into the system, at the outlets of all pre-reservoirs, as well as in the main reservoir. The newly installed monitoring system serves both scientific monitoring and process studies, as well as reservoir management. Particular emphasis is paid to the monitoring of short-term dynamics and many variables are measured at high temporal resolution. As an example, we quantitatively documented a flood event which mobilised high loads of dissolved organic carbon and changed the characteristics of the receiving reservoir from eutrophic to dystrophic within a few days. This event could have been completely missed by conventional biweekly sampling programs, but is relevant for biogeochemical fluxes at the catchment scale. We also show that the high frequency data provide a deeper insight into ecosystem dynamics and lake metabolism. The Rappbode Reservoir Observatory; moreover, offers a unique study site to apply, validate, and develop state of the art lake models to improve their predictive capabilities.  相似文献   

Satellite data and geographic information systems for fire and resource management in the Canadian arctic     

Helmut Epp  Rick Lanoville 《国际地球制图》2013,28(2):97-103

Abstract

A method of analyzing remotely sensed data, a geographic information system, and an intelligent fire management system have been developed to provide integrated resource data for fire and other resources management. Natural and cultural features were digitized from 1:50,000 topographic maps using a geographic information system (GIS) to cover the 29 communities below the tree line in the western Canadian Arctic. Landsat Thematic Mapper data covering the same area were classified into land cover or fuel types. Detailed information on each fire such as location, area burned, date of discovery, fire number, fire zone, fire class and source of ignition was obtained and added to each map sheet as attribute data. A generalized vegetation cover map using NOAA AVHRR data was also obtained. The Intelligent Fire Management Information System (IFMIS) integrates relational data bases, geographic information display, and expert systems. It also has a spatial analysis procedure for forest fire preparedness planning. Linking the weather to the forest fuels through the Fire Weather Index system (FWI) and the Fire Behaviour Prediction System (FBPS), fire danger and fire behaviour are calculated and displayed, cell‐by‐cell. Values‐at‐risk and fire suppression resources are used in the dispatching and planning component of the system. The planning component allows the user to evaluate the coverage of fire suppression resources under the prevalent forecast fire behaviour conditions. Through the integration of data from the above systems, a set of maps were created which were used to analyze fire behaviour potential, identify fire hazards, and provide a basis for settlement protection strategies within the context of other land use activities such as wildlife harvesting and recreational activities.  相似文献   

Using embodied HANPP to analyze teleconnections in the global land system: Conceptual considerations     

Helmut Haberl  Karl-Heinz Erb  Fridolin Krausmann  Stefan Berecz  Nikolaus Ludwiczek  Joan Martínez-Alier 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):119-130

Geografisk Tidsskrift—Danish Journal of Geography 109(2):119–130, 2009

In our rapidly globalizing world economy activities in one region have increasingly important effects on ecological, economic or social processes elsewhere, an effect which we here denote as ‘teleconnections’ between different regions. Biomass trade, one of the causes behind such teleconnections, is currently growing exponentially. Integrated analyses of changes in the global land system are high on the agenda of sustainability science, but a methodological framework for a consistent allocation of environmental burdens related to the consumption and production of biomass between regions has not been put forth to date. The concept of the ‘embodied human appropriation of net primary production’ (abbreviated ‘embodied HANPP’ or ‘eHANPP’) allows for the assessment of the ‘upstream’ effects on ecosystem energetics associated with a particular level of biomass consumption or with a given biomass-based product. This concept is based on HANPP and its two components: (1) productivity changes resulting from land conversion (ΔNPP_LC), and (2) harvest of biomass in ecosystems (NPP_h). HANPP, defined as the sum of ΔANPP_LC and NPP_h in any given territory, is indicative of the intensity with which humans use the land for their purposes. eHANPP is defined as the NPP appropriated in the course of biomass production, encompassing losses along the production chain as well as productivity changes induced through land conversion or harvest. By making the pressure exerted on ecosystems associated with imports and exports visible, eHANPP allows for the analysis of teleconnections between producing and consuming regions. This article puts forward the eHANPP concept, illustrates its utility for integrated socioecological land-change research based on top-down data on global HANPP and biomass consumption, and discusses the possibilities and challenges related to its quantification in bottom-up approaches.  相似文献   

Morphogenesis of typical winter and summer snow surface patterns in a continental alpine environment     

Ute C. Herzfeld  Helmut Mayer  Nel Caine  Mark Losleben  Tim Erbrecht 《水文研究》2003,17(3):619-649

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Terrestrial carbon-isotope records from coastal deposits (Algarve, Portugal): a tool for chemostratigraphic correlation on an intrabasinal and global scale     

Ulrich Heimhofer  Peter A. Hochuli  Stefan Burla  Nils Andersen  Helmut Weissert 《地学学报》2003,15(1):8-13

ABSTRACT The carbon-isotope signature of terrestrial organic matter (OM) offers a valuable tool to develop stratigraphic correlations for near-shore deposits. A mid-Cretaceous coastal succession of the western Algarve Basin, Portugal, displays a marked negative δ¹³C excursion ranging from − 21.2‰ to − 27.8‰ in the Early Aptian followed by two shifts towards higher values (up to − 19.3‰) during the Early and Late Aptian, respectively. The dominance of cuticle and leaf debris in the bulk OM fraction is confirmed by optical studies, Rock-Eval pyrolysis and by comparison with the δ¹³C signature of four different types of fossilized land-plant particles. Correlation of two terrestrial δ¹³C_bulk OM records from different study sites leads to a significant enhancement of the intrabasinal stratigraphic correlation within the Algarve Basin. Three prominent excursions in the Portuguese records can be correlated with existing δ¹³C curves from pelagic and terrestrial environments. The general carbon-isotope pattern is superimposed by small-scale fluctuations which can be explained by compositional variations within the OM.  相似文献   

Drilling and Grouting Works for Pressurised Groundwater Conditions of the Semmering Base Tunnel     

Wannenmacher  Helmut  Entfellner  Manuel  Hauer  Hannes 《Geotechnical and Geological Engineering》2022,40(9):4377-4391

Geotechnical and Geological Engineering - The Semmering Base Tunnel (SBT), with a total length of 27.3 km, is one of the leading construction projects of the Baltic-Adriatic Railway...  相似文献   

Significance of flow rule for the passive earth pressure problem     

Schmüdderich  Christoph  Tschuchnigg  Franz  Schweiger  Helmut F. 《Acta Geotechnica》2022,17(1):81-92

Acta Geotechnica - Determination of earth pressures is one of the fundamental tasks in geotechnical engineering. Although many different methods have been utilized to present passive earth pressure...  相似文献   

The pointing system of the Herschel space observatory     

Miguel Sánchez-Portal  Anthony Marston  Bruno Altieri  Hervé Aussel  Helmut Feuchtgruber  Ulrich Klaas  Hendrik Linz  Dieter Lutz  Bruno Merín  Thomas Müller  Markus Nielbock  Marc Oort  Göran Pilbratt  Micha Schmidt  Craig Stephenson  Mark Tuttlebee 《Experimental Astronomy》2014,37(2):453-479

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