Modelling the responses of mature forest trees to air pollution     

Heiner Schäfer Dr.  Hartmut Bossel  Holger Krieger  Norbert Trost 《GeoJournal》1988,17(2):279-287

Systems analysis of the responses of forest trees to air pollutants led to mathematical models which represent the essential life processes of mature trees (photosynthesis, respiration, growth etc.) under ‘normal’ conditions and — especially — under pollution strees. Computer simulations using these models have made it possible to test and analyse the consequences of — known or hypothetical — pollution effects. The simulation runs have led to the identification of three distinct behavioural modes (growth, stagnation, breakdown) and corresponding stable and unstable system states. The results have produced new insights and contributed to the understanding of the dieback process of spruce and beech trees. The presentation will concentrate on the most recent and most complex of the hitherto existing models, theBeech model.  相似文献   

Die Kontamination von Nord- und Ostsee durch den Reaktorunfall von Tschernobyl     

Dr. Hartmut Nies  Christoph Wedekind 《Ocean Dynamics》1987,40(6):277-288

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Bathymetrie und Geomorphologie des NOAMP-Gebietes,Westeuropäisches Becken (17° W bis 22° W, 46° N bis 49° N)     

Dr. Hartmut Heinrich 《Ocean Dynamics》1986,39(5):183-196

Zusammenfassung Im Westeuropäischen Becken wurden bathymetrische Vermessungen und geomorphologische Untersuchungen zur Unterstützung eines ozeanographischen Meßprogramms (NOAMP) des Deutschen Hydrographischen Instituts durchgeführt. Für das zentrale Arbeitsgebiet wurde mit dem SEA BEAM-System eine sehr exakte Tiefenkarte erstellt. Die Karte der weiteren Umgebung ergab sich aus den NBS-Lotungen während der Profilfahrten des hydrographischen Meßprogramms.Die bathymetrischen Karten zeigen Wassertiefen zwischen 3500 und 4900 m an. Das Relief ist damit deutlich rauher, als es aus bisherigen Vermessungen zu erwarten war. Es herrschen NNE-SSW-streichende Strukturen vor, die parallel zum Mittelatlantischen Rücken verlaufen. Ab und zu werden diese durch breite, E-W-verlaufende Senken geschnitten. Bei diesen Senken handelt es sich vermutlich um derzeit inaktive ozeanische Bruchzonen.Die basaltische Kruste hat im Zentralgebiet ein paläozänes bis eozänes Alter (Magnetanomalie 26 bis 21). Die basaltischen Rücken tragen eine ca. 30 m mächtige Sedimentdecke, die das schroffe Krustenrelief noch nicht geglättet hat. Tiefergelegene Rinnen und Senken besitzen durch Sedimentumlagerung und (nördlich 47° N) durch Turbiditzufuhr aus dem Maury-Channel-System südlich von Island eine mehr als 150 m mächtige Sedimentfüllung.

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Bathymetric and physiographic charting in the NOAMP area, West European Basin (17° W to 22° W, 46° N to 49° N)

Summary The Deutsches Hydrographisches Institut (DHI), Hamburg, is carrying out an oceanographic measurement programme in the NE Atlantik (NOAMP) in order to compute the transportation paths of dissolved and particulate substances from the ocean bottom up to surface layers. One of the main tasks, to resolve the movements of the bottom currents, required detailed knowledge of the structure of the ocean floor. Therefore, the oceanographic data collection was accompanied by bathymetric charting and a geophysical site survey (continuous profiling of reflection seismic, gravity, and orientation of magnetism) of the central area of investigation. The mapping of the central NOAMP area was carried out with the SEA BEAM system (RV Polarstern, RV Sonne). NBS soundings, recorded during the hydrographic cruises, were evaluated for a map of the outer vicinity.As the most important result, the mapping revealed a much more sophisticated relief than was expected from known charts. The water depth range between 3500 and 4900 m. A system of ridges and furrows, with a mean crest-to-crest distance of 10 nautical miles, trends parallel to the Mid-Atlantic Ridge (NNE to SSW). This system is cut each 50 nautical miles by broad E-W striking valleys. The ridges climb about 300 to 400 m above the bottom of the furrows. Some peaks sitting on top of the ridges rise up to the shallowest depths of 3500 m.The internal cores of the ridges consist of basaltic ocean crust, as can be seen by the relative increases of the Bouguer gravity. In the central NOAMP area, the age of the crust is Paleocene to Eocene (magnetic anomalies 26 to 21). The E-W striking valley at 47° 30 N is interpreted as a fossil fracture zone, due to the Z-like bending of the magnetic anomalies.The sediment cover is rather thin on elevations (about 30 m). Therefore, the rough microtopography of the basaltic crust is not yet buried. Downslope mass transport of sediment by currnets and submarine slides raised the sediment thickness in the deeper furrows to more than 100 m, and smoothed out the floor. North of 47° N, there is an additional supply of sediment by turbidity currents from the depositional Maury Channel system south of Iceland.

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Relevés bathymétriques et physiographiques dans la zone NOAMP, bassin européen Ouest (17° W à 22° W, 46° N à 49° N)

Résumé Le Deutsches Hydrographisches Institut (DHI) de Hamburg, est en train d'exécuter un programme de mesures océanographiques dans l'Atlantique Nord-Est (NOAMP), dans le but de déterminer le cheminement du transport des substances dissoutes et particulaires du fond de l'océan vers les couches de surface. L'une des principales tâches, étant la détermination des déplacements des courants de fond, elle exigeait une connaissance détaillée de la structure du fond de l'océan. En conséquence, la collecte des données océanograhiques fut accompagnée de relevés bathymétriques et d'un levé géophysique sur le site (profils continus de réflexion sismique, gravité, orientation du champ magnétique) de la zone centrale d'investigation. La cartographie de la zone centrale NOAMP a été réalisée à l'aide du sondeur «SEA BEAM» (RV «Polarstern», RV «Sonne»). Les sondages NBS enregistrés au cours des campagnes hydrographiques, étaient évalués pour une carte du voisinage extérieur.Le résultat le plus important, révélé par la cartographie, était un relief beaucoup plus complexe que celui auquel on pouvait s'attendre à la lecture des cartes existantes. La profondeur était comprise entre 3500 et 4900 m. Un système de dorsales et de sillons, avec une distance moyenne de crête à crête de 10 milles marins, s'étire parallèlement à la dorsale médiane de l'Atlantique (du NNE au SSW). Ce système est interrompu tous les 50 milles marins par de larges vallées de direction Est-Ouest. Les dorsales culminent de 300 à 400 m au-dessus du fond des sillons. Quelques pics situés au sommet des dorsales remontent vers les profondeurs les plus faibles qui sont de 3500 m.La structure interne des dorsales consiste en une croûte de basalte océanique comme cela peut être observé par l'augmentation relative de l'anomalie de Bouguer. Dans la partie centrale de la zone NOAMP, l'âge de la croûte s'étale du paléocène à l'éocène (les anomalies magnétiques de 26 à 21). La vallée de direction Est-Ouest située en 47° 30 N, est interprétée comme une zone de fracture fossile, attribuable à la sinuosité, en forme de Z, des anomalies magnétiques.La couverture sédimentaire est plutôt mince sur les hauteurs (de l'ordre de 30 m). C'est pourpuoi, la microtopographie grossière de la croûte basaltique n'est pas encore enfouie. Le transport en masse des sédiments suivant la pente descendante du aux courants et aux glissements sous-marins ont augmenté l'épaisseur du sédiment dans les sillons les plus profonds jusqu'à plus de 100 m et ont «lissé» le fond. Il existe au Nord de 47° N, un apport supplémentaire de sédiments amené par des courants de turbidité provenant du dépôt de Maury Channel au Sud de l'Islande.

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Structure and composition of the continental crust in East China   总被引：14，自引：0，他引：14  

Shan Gao  Tingchuan Luo  Benren Zhang  Hongfei Zhang  Yinwen Han  Zidan Zhao  Hartmut Kern 《中国科学D辑(英文版)》1999,42(2):129-140

Crustal structures of nine broad tectonic units in China, except the Tarim craton, are derived from 18 seismic refraction profiles including 12 geoscience transects. Abundances of 63 major, trace and rare earth elements in the upper crust in East China are estimated. The estimates are based on sampling of 11 451 individual rock samples over an area of 950 000 km², from which 905 large composite samples are prepared and analyzed by 13 methods. The middle, lower and total crust compositions of East China are also estimated from studies of exposed crustal cross sections and granulite xenoliths and by correlation of seismic data with lithologies. All the tectonic units except the Tarim craton and the Qinling orogen show a four-layered crustal structure, consisting of the upper, middle, upper lower, and lowermost crusts. P-wave velocities of the bulk lower crust and total crust are 6.8–7.0 and 6_:4–6.5 km/s, respectively. They are slower by 0.2–0.4 km/s than the global averages. The bulk lower crust is suggested to be intermediate with 58% SiO₂ in East China. The results contrast with generally accepted global models of mafic lower crusi. The proposed total crust composition in East China is also more evolved than previous estimates and characterized by SiO₂=64%, a significant negative Eu anomaly (Eu/Eu* = 0.80), deficits in Sr and transition metals, a near-arc magma La/Nd ratio (3.0), and a calculatedμ(²³⁸U/²⁰⁴Pb) value of 5. In addition, it has the following ratios of element pairs exhibiting similar compatibility, which are identical or close to the primitive mantle values: Zr/Hf=37, Nb/Ta=17.5, Ba/Th=87, K/Pb=0.12x10⁴, Rb/Cs=25, Ba/Rb=8.94, Sn/Sm=0.31, Se/Cd=1.64, La/ As=10.3, Ce/Sb=271, Pb/Bi=57, Rb/TI=177, Er/Ag=52, Cu/Au=3.2×10⁴, Sm/Mo=7.5, Nd/W=40, CI/Li=10.8, F/Nd=21.9, and La/B=1.8. Project supported by the National Natural Science Foundation of China (Grant Nos. 49625305, 49573183, 49673184, 49794043), the State Comission of Education, the Ministry of Geology and Mineral Resources of China (Grant No. 850514), the Open Laboratory of Constitution, Interaction and Dynamics of the Crust-Mantle System, and the Alexander-von-Humboldt Foundation of Germany.  相似文献   

Stand und Perspektiven der Sekundärstoffforschung an marinen Mikroorganismen (Zusammenfassung)     

Laatsch  Hartmut 《Ocean Dynamics》1999,51(10):99-99

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Holothuroidea (Echinodermata) of the Peru Basin - Ecological and Taxonomic Remarks Based on Underwater Images     

Hartmut Bluhm  &Andrej Gebruk 《Marine Ecology》1999,20(2):167-195

The megabenthos plays an important role in the abyssal ecosystem. The holothuroids have been proposed as indicators of physical disturbance of the seabed caused, for example, by commercial deep-sea mining of manganese nodules. Environmental studies at seabed mining claims have resulted in numerous still photographs that provide an overview of the megabenthos in manganese nodule fields. Data from these investigations and from the large-scale disturbance and recolonization experiment DISCOL have been used to summarize knowledge of the taxonomy and ecology of holothurians at manganese nodule sites.  相似文献   

条斑紫菜孢子体与配子体光合系统Ⅱ(PSⅡ)稳定性研究     

柳葵葵  张海霞  Verena Linhar  Hartmut Michel  彭国宏 《海洋科学》2007,31(10):25-28

膜蛋白是生物领域研究中的热点和难点。在光合作用研究中,对于藻类个体发育过程中光合膜蛋白结构和功能的变化所知甚少,其中的一个限制因素是能否纯化得到大量高活性的稳定且均一的光合膜蛋白。作者从条斑紫菜(Porphyra yezoensis)孢子体和配子体中分离纯化得到光合系统(PSⅡ)复合物,并研究了其完整性和放氧活性。结果表明,孢子体和配子体的PSⅡ复合物,在4℃条件下保存比在-80℃下保存放氧活性高,稳定性高。配子体PSⅡ复合物,在-80℃保存第6天就已经没有放氧活性,而孢子体PSⅡ复合物仍有放氧活性。对4℃下保存的PSII复合物进行分子筛柱层析,室温吸收光谱测定以及放氧活性测定,发现随着放氧活性逐渐降低,蛋白大分子有聚合现象。室温吸收光谱表明经过长期的保存,吸收峰向短波长方向偏移,叶绿素易降解成为脱镁叶绿素  相似文献   

Tantalite-(Mn) from the Borborema Pegmatite Province,northeastern Brazil: conditions of formation and melt- and fluid-inclusion constraints on experimental studies     

Rainer Thomas  Paul Davidson  Hartmut Beurlen 《Mineralium Deposita》2011,46(7):749-759

Carbon dioxide-rich fluid and carbonate-rich aluminosilicate melt inclusions in tantalite-(Mn) from the Alto do Giz pegmatite in the Borborema Pegmatite Province, northeastern Brazil were investigated to constrain the formation of the host crystals. The results demonstrate that in the Alto do Giz pegmatite, water- and alkaline carbonate-rich fluids and melts are responsible for the transport and deposition of tantalite-(Mn) at temperatures around 600°C and about 4 kbar. Moreover, evidence is presented to show that during crystallization of the tantalite-(Mn), three different components coexisted, which are now trapped as separate inclusions: two immiscible silicate melts (types A and B melt inclusions) and a CO₂-rich aqueous fluid. We hypothesize that immiscible fluid separation may have been a critical factor in producing the water- and alkaline carbonate-rich fluids and melts necessary for Ta and Nb transport. Since the tantalite-(Mn) crystallized during pegmatite formation, this mechanism must also have implications for pegmatite genesis in general.  相似文献   

Topographic characteristics of laboratory induced shear fractures     

Ganglin Chen  Hartmut Spetzler 《Pure and Applied Geophysics》1993,140(1):123-135

The topography of laboratory induced shear fracture surfaces of Westerly granite was studied. Three types of fracture surfaces were examined: (1) a fresh fracture from the shear failure of an intact sample under polyaxial loading (₂ = 40 MPa > ₃ = 15 MPa); (2) a shear fracture subjected to frictional sliding of 100 m under polyaxial loading; (3) a shear fracture subjected to frictional sliding of 800 m under conventional triaxial loading (₁ > ₂ = ₃ = 40 MPa). Both sliding distances are within the range of the grain size of Westerly granite. The results are represented by a power spectral method.Similar to the power spectra from natural rock surfaces, the power spectra of the induced shear fracture surfaces fall off about 2 orders of magnitude per decade increase in spatial frequency. No corner frequency exists in the power spectra over a spatial frequency range from that corresponding to the profile length to the Nyquist frequency. A slope break in the power spectrum was identified, however. It separates a steeper low frequency segment from a less steep high frequency segment. The spatial frequency at the slope break corresponds to a wavelength of several hundred microns which is on the scale of the microcracking and contact breaking on the fractures. Upon re-examining power spectra of natural fault traces and fault surfaces obtained in previous studies, we noted similar slope breaks. We suggest that this slope break may have significant implications in the scaling problem. Both the induced fracture surfaces and natural faults exhibit topographic characteristics different from those of sawcut surfaces, which have been widely used in laboratory rock friction experiments. In the present study, we observed that even a small amount of sliding (less than a grain size) already results in significant mismatches between the paired sliding surfaces in the direction normal to sliding.  相似文献   

From magnitudes and redshifts of supernovae,their light-curves,and angular sizes of galaxies to a tenable cosmology     

Hartmut Traunmüller 《Astrophysics and Space Science》2014,350(2):755-767

Early physical cosmologies were based on interpretations of the cosmic redshift for which there was insufficient evidence and on theories of gravitation that appear to be falsified by galactic dynamics. Eventually, the big bang paradigm came to be guarded against refutation by ad hoc hypotheses (dark matter, cosmic inflation, dark energy) and free parameters. Presently available data allow a more satisfactory phenomenological approach. Using data on magnitude and redshift from 892 type Ia supernovae, it is first shown that these suggest that the redshift factor (1+z) is simply an exponential function of distance and that, for “standard candles”, magnitude m=5log[(1+z)ln(1+z)]+const. While these functions are incompatible with a big bang, they characterize certain tired light models as well as exponential expansion models. However, the former are falsified by the stretched light curves of distant supernovae and the latter by the absence of a predicted 1+z increase in the angular sizes of galaxies. Instead, the observations suggest that physical processes speed up and objects contract uniformly as an exponential function of time, standards of measurement not excluded, and only free waves being excepted. Distant events proceed, then, more slowly, while angular sizes remain unaffected, approximately as observed. Since all objects contract in proportion, the Universe retains a static appearance. A corresponding physical theory, which should also explain galactic dynamics, remains yet to be derived from first principles. A way to do this, satisfying also Mach’s principle, is vaguely suggested.  相似文献