The Mesozoic–Cenozoic structural framework of the Bay of Kiel area, western Baltic Sea     

Martin Bak Hansen  Holger Lykke-Andersen  Ali Dehghani  Dirk Gajewski  Christian Hübscher  Morten Olesen  Klaus Reicherter 《International Journal of Earth Sciences》2005,94(5-6):1070-1082

A dense grid of multichannel high-resolution seismic sections from the Bay of Kiel in the western Baltic Sea has been interpreted in order to reveal the Mesozoic and Cenozoic geological evolution of the northern part of the North German Basin. The overall geological evolution of the study area can be separated into four distinct periods. During the Triassic and the Early Jurassic, E–W extension and the deposition of clastic sediments initiated the movement of the underlying Zechstein evaporites. The deposition ceased during the Middle Jurassic, when the entire area was uplifted as a result of the Mid North Sea Doming. The uplift resulted in a pronounced erosion of Upper Triassic and Lower Jurassic strata. This event is marked by a clear angular unconformity on all the seismic sections. The region remained an area of non-deposition until the end of the Early Cretaceous, when the sedimentation resumed in the area. Throughout the Late Cretaceous the sedimentation took place under tectonic quiescence. Reactivated salt movement is observed at the Cretaceous Cenozoic transition as a result of the change from an extensional to compressional regional stress field. The vertical salt movement influenced the Cenozoic sedimentation and resulted in thin-skinned faulting.  相似文献   

Early German plans for southern observatories     

G. Wolfschmidt 《Astronomische Nachrichten》2002,323(6):548-554

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Nitrogen cycling in the German Bight (SE North Sea) — Clues from modelling stable nitrogen isotopes     

Johannes Pätsch  Alexandra Serna  Kirstin Dähnke  Tim Schlarbaum  Astrid Johannsen  Kay-Christian Emeis 《Continental Shelf Research》2010

Nitrogen isotope values (δ¹⁵N) of surface sediments in the German Bight of the North Sea exhibit a significant gradient from values of 5–6‰ of the open shelf sea to values above 11‰ in the German Bight. This signal has been attributed to high reactive N (N_r) loading enriched in ¹⁵N from rivers and the atmosphere. To better understand the processes that determine the intensity and spatial distribution of δ¹⁵N anomalies in surface sediments, and to explore their usefulness for reconstructions of pristine N-input from rivers, we modeled the cycling of the stable isotopes ¹⁴N and ¹⁵N in reactive nitrogen through the ecosystem of the central and southern North Sea (50.9–57.3°N, 3.4°W−9.2°E) for the year 1995. The 3D-ecosystem model ECOHAM amended with an isotope-tracking module was validated by δ¹⁵N data of surface sediments within the model domain. A typical marine value (δ¹⁵N_nitrate=5‰) was prescribed for nitrate advected into the model domain at the seaside boundaries, whereas δ¹⁵N_nitrate of river inputs were those measured bi-monthly over 1 year; δ¹⁵N values of atmospheric deposition were set to 6‰ and 7‰ for NO_x and NH_y, respectively. The simulated δ¹⁵N values of different nitrogen compounds in the German Bight strongly depend on the mass transfers in the ecosystem. These fluxes, summarized in a nitrogen budget for 1995, give an estimate of the impacts of hydrodynamical and hydrological boundary conditions, and internal biogeochemical transformations on the nitrogen budget of the bight.  相似文献   

Temporal variability of micro- and nanoplankton in the German Bight in relation to hydrographic structure and nutrient changes   总被引：2，自引：0，他引：2  

Hickel  Wolfgang 《ICES Journal of Marine Science》1998,55(4):600-609

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Nutrient dynamics in the Sylt-Rømø Bight ecosystem,German Wadden Sea: An ecological network analysis approach     

Dan Baird  Harald Asmus  Ragnhild Asmus 《Estuarine, Coastal and Shelf Science》2008

Carbon, nitrogen, and phosphorus flow networks, consisting of 59 compartments, were constructed for the Sylt-Rømø Bight, a large shallow sea in the German Wadden Sea. These networks were analysed using ecological network analysis. Each network depicts the standing stock of each component in the ecosystem, and the flows between them. The trophic efficiency by which material is utilised in the Bight increase from 3%, to 6% to 17% for C, N and P, respectively. The number of cycles though which these elements pass increase from 1 197 for carbon, to 414?744 and 538?800 for nitrogen and phosphorus, respectively. The Finn Cycling Index, reflecting the amount of material recycled as a fraction of the total system activity, TST, increases from 17% for carbon, to 43% for nitrogen, to 81% for phosphorus. Other system level attributes such as the Average Path Length, the Average Internal Mutual Information, Relative Ascendancy, Relative and Normalized Redundancy, show an increase from the carbon to the nitrogen to the phosphorus networks. Phosphorus is tightly cycled over longer pathways than the other two elements, and also has the longest residence time in the Bight. Postulated differences between the behaviour of energy (or carbon) and biogeochemical networks in coastal ecosystems are evident from the results obtained from ecological network analysis.  相似文献   

Street petrol station shops as an alternative to missing local food suppliers – Contribution to the German discourse on ‘Daseinsvorsorge’: A German view     

《Applied geography (Sevenoaks, England)》2015

Services of general interest fulfill people's daily needs and are important for their well-being. In Germany, interacting socioeconomic and demographic processes currently lead to a spatial concentration of such services. Rural areas are particularly affected, resulting in a deterioration of living conditions. Nevertheless, although in the media and in policy these processes are intensely discussed against the background of the German political and scientific discourse on ‘Daseinsvorsorge’, little is known about their dimensions. However, such knowledge is important for both policy and scientific policy advice, as ‘Daseinsvorsorge’ is a key concept in German spatial planning discourse, rooted in the normative political goal of guaranteeing comparable living conditions throughout Germany. This goal includes the aim of ensuring a sufficient offering of services indispensable for life throughout the country. One subject area where a spatial concentration can be observed is retail food sales. As a consequence, especially in rural areas, the network of food shopping locations becomes more wide meshed. Against this background, the German petrol-sector claims that in rural regions, petrol station shops (PSS) might replace a missing local food retailer. Based on the data from an accessibility analysis of petrol stations, supermarkets and discounters, together with considerations on the assortment of PSS, the article analyses the potential of such shops to fulfill this function in rural Germany through the lens of ‘Daseinsvorsorge’. The analysis reveals the following: (1) PSS still mainly serve impulse shopping needs, offering only a very limited assortment of staple foods; (2) in the majority of regions with no supermarket or discounter accessible by foot, PSS are also not accessible by foot; and (3) by car, the picture is very similar. Considering these points, it can be concluded that in Germany, PSS cannot at this time fully replace a missing local retail trade, especially in rural areas.  相似文献   

The 1989 German Bight invasion of Muggiaea atlantica   总被引：4，自引：0，他引：4  

Greve  Wulf 《ICES Journal of Marine Science》1994,51(4):355-358

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Establishment of thermophilic phytoplankton species in the North Sea: biological indicators of climatic changes?   总被引：3，自引：0，他引：3  

Nehring  Stefan 《ICES Journal of Marine Science》1998,55(4):818-823

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近代德国地理学的理论与贡献     

林锦屏  周美岐  易琦  钟竺君  季文华 《世界地理研究》2021,30(5):957-965

德国是近代自然地理学的发源地,也是人文地理学的故乡。近代德国地理学不仅助推了德国社会经济的发展,还为世界各国地理学的发展奠定了理论基础,推动了地理学的科学化、系统化与全球化。本文运用文献计量法综述国内外1975—2019年关于近代德国地理学的539篇文献,从年度载文量、研究者国别、研究方向和研究方法四方面入手,突出时间顺序与空间差异,系统梳理与凝练近代德国地理学家的理论与重要贡献,结果表明：近代德国自然地理学与人文地理学的经典理论,尤其是地质地貌、地学革命,以及区域、景观与环境三大学派、区位理论、地缘政治等领域对人类做出了卓越的贡献,近代德国地理学的理论与研究方法值得我们借鉴与思考。  相似文献   

WHY WAS HUMBOLDT FORGOTTEN IN THE UNITED STATES?*     

Sandra Nichols 《Geographical review》2006,96(3):399-415

ABSTRACT. In the nineteenth century Alexander von Humboldt was acclaimed as “the second Columbus” and “the scientific discoverer of America.” His prestige and fame were such that on 14 September 1869, the hundredth anniversary of his birth, a grand celebration was held with parades, speeches, concerts, and the unveiling of memorials in cities across the country. Humboldt's popularity in the United States endured for the remainder of the nineteenth century, but he dropped from public consciousness in the twentieth century. To account for the eclipse of Humboldt's fame in the United States three hypotheses are discussed: a shift in the character of scientific endeavor; the quality of Humboldt's written work; and the rise of anti‐German sentiment with a concurrent rush to “de‐Germanize” the United States in the early twentieth century.  相似文献