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11.
Zbigniew W. Kundzewicz Hans-Joachim Schellnhuber Anastasia Svirejeva-Hopkins 《Climate Policy》2013,13(1):81-90
Abstract Since the World Climate Change Conference held in the autumn of 2003 in Moscow, Russian Federation, the fate of international climate policy architecture designed around the Kyoto Protocol hangs in the balance. After the withdrawal of the USA from the Kyoto Protocol, the condition of its ratification cannot be met without the Russian Federation. There has been a considerable uncertainty as to Russia's intentions regarding ratification of Kyoto. In this contribution, an attempt is made to identify the Russian motives and concerns, and explain their attitudes regarding the Kyoto Protocol. Pressures against and for ratification are discussed. Finally, a few comments are made about the future of the efforts to solve the global environmental problem of protecting the Earth's climate. 相似文献
12.
Abdulrahman Al-Safarjalani Sobhi Nasir Thomas Fockenberg Hans-Joachim Massonne 《Chemie der Erde / Geochemistry》2009,69(4):359-375
The chemical bulk rock composition of 37 xenoliths, brought from depths of 25–30 km to the surface by penetrating Cenozoic alkali basaltic magma, from the Shamah Harrat, southwestern Syria, was determined by XRF spectroscopy. The geochemical character of these xenoliths points to original marls and within-plate igneous rocks. To obtain the mean chemical composition of the corresponding upper portion of the lower crust, the compositions of the 37 xenoliths were averaged and a leucogranitic and upper crustal component was added to account for assimilation by the Cenozoic magmas. This mean is more basic (SiO2—50.5 wt%) and richer in HFSE, LREE, and LILE compared to compositions of the lower crust given by Taylor and McLennan [1985. The Continental Crust: Its Composition and Evolution. Blackwell, Oxford, 312pp.] and Rudnick and Gao [2005. Composition of the continental crust. In: Rudnick, R.L. (Ed.), The Crust. Treatise on Geochemistry, vol. 3. Elsevier, Amsterdam, pp. 1–64]. Calculations of the seismic compressional-wave velocity from our compositional mean, using the PERPLE_X computer software, yielded values around 6.85 km/s, which are in accordance with reported seismic studies for the corresponding depth levels (6.7–7.1 km/s). 相似文献
13.
Pinto Viter Magalhães Massonne Hans-Joachim Wildner Wilson Hartmann Léo Afraneo Debruyne David Theye Thomas 《Mineralogy and Petrology》2019,113(6):765-782
Mineralogy and Petrology - Mafic-ultramafic intrusions within continental flood basalt terrains are frequently associated with Cu-Ni-PGE mineralization. This study aims to constrain the... 相似文献
14.
Hans-Joachim Elster 《Aquatic Sciences - Research Across Boundaries》1949,11(3-4):352-360
Zusammenfassung Erh?ht man die Intensit?t der Befischung in einem Gew?sser, so steigt der durchschnittliche Fangertrag nicht im selben Verh?ltnis,
sondern um so langsamer, je h?her die Befischungsintensit?t schon vorher war. Diese Beziehungen werden mathematisch formuliert.
Es werden Tabellen aufgestellt, die den neuen Befischungskoeffizienten in Abh?ngigkeit vom alten und die ?nderung des Ertrages
pro Fischer bzw. pro Befischungseinheit nach dem Wechsel der Befischungsintensit?t zu berechnen gestatten. Schlie?lich werden
die einschr?nkenden Bedingungen besprochen, unter denen diese theoretischen Beziehungen in der Praxis angewendet werden k?nnen.
Summary By increasing the intensity of fishing in a lake the average catch will not increase in the same ratio, but the slower the higher the intensity of fishing has been before. These relations are brought to a mathematical formula. Tabels are made which allow to compute the new coefficient of fishing depending on the old and the change of the catch per fisherman, resp. per unity of fishery after the changing of the intensity of fishing. After all one is treating the restrictive conditions by which these theoretical relations may be employed in practice. Die Arbeit wurde Herrn Oberregierungsrat Dr. F.Lücke, Direktor des Instituts für Fischverarbeitung in Hamburg-Altona, zum 60. Geburtstag gewidmet.相似文献
15.
Hans-Joachim Bürkner 《GeoJournal》2000,50(2-3):105-108
Migration flows from western Europe, the United States and Canada to east central Europe have received little attention so
far. But numbers are now considerable and in the context of globalisation it seems appropriate to conceptualise communities
of Westerners in terms of transnational social spaces as defined by Glick Schiller et al. Study of Americans in Prague reveals
three main groups: enterprise managers, lifestyle migrants and entrepreneurs in small and medium-sized enterprises. All are
engaged in a variety of different processes of community-building, often with clear trends towards a new transnationalism.
Yet, the individual attempt to live in two societies is limited by the marked boundaries of the communities and by the degree
of social exclusion which they experience from the majority population.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
An enrichment of light rare earth elements (LREE) is characteristic for most of the acidic, Fe- and SO4-rich pit lakes and groundwaters in the lignite mining area of Lower Lusatia (Germany). One of these acidic lakes – the pit lake “RL 1223” – has a strong thermal and chemical stratification. The upper water layer (0–9 m) shows pH values of about 3 during all seasons. The monimolimnion (10–17 m) of the lake is anoxic and has pH values of about 7. The rare earth element (REE) patterns of the upper lake water show enriched LREE (LaN/YbN = 1.6) whereas the opposite patterns (depletion of LREE, LaN/YbN = 0.4) are found in the anoxic water of the monimolimnion. Experiments were conducted to observe the behaviour of REE during Fe oxidation in water from the monimolimnion (depth 14 m). The sampled monimolimnion water was placed in plastic bottles, and the changing water chemistry was observed for 40 weeks after sampling. Due to the initial anoxic conditions almost all Fe precipitated in the investigated water, and the pH value decreased from about 7 to 3 during the oxidation. The Fe precipitates are identified as ferrihydrite which is transformed into goethite within the oxidation process. Stable pH conditions (pH 3.0) were reached after about 10 weeks of oxidation.The original REE patterns of the investigated water are generally reflected in the Fe precipitates collected at the beginning of the experiment as well as after up to 40 weeks of oxidation. However, in the corresponding water LREE were temporally enriched with a maximum LaN/YbN ratio of 1.0 and a maximum LaN/SmN ratio of 2.3 after 6 weeks of oxidation time (pH 3.8–4.9). Although complex geochemical changes took place between the start and the end of the experiment REE patterns observed at these points in time are nearly identical. These differences of the REE pattern can be explained by the sampling procedure. The experimental findings can be transmitted to the mining dump aquifers of the study area where geochemical conditions comparable to the experimental oxidation time from 3 to 6 weeks are found and hydrous ferric oxides are precipitating. Groundwater passing through the mining dumps can preferentially desorb LREE from the Fe precipitates and display the typical LREE enrichment and carry it to the epilimnion of the acidic pit lakes in Lower Lusatia. 相似文献
17.
Pascal Kremer Jan Schlüter Paolo Racca Hans-Joachim Fuchs Christian Lang 《Climatic change》2016,135(3-4):481-491
18.
影响湖相沉积岩中有机碳分布的主要因素--以三水盆地为例 总被引:21,自引:0,他引:21
湖相沉积中的有机质含量随有机质堆积条件变化而发生波动。本以三水盆地下第三系布心组二段地层粉列,对其作高分辨率岩芯取样并结合地球化学方法,分析生物学因素对有机碳分布的影响。在较干燥的气候条件下,水生浮游生物是有机质的主要来源,由于此时湖泊与海洋沟通,出现半咸水环境,硫酸盐还原作用显,不利于有机质保存。所取岩芯段的中上部即是这种情况,以低TOC和高SRI值为特征。而当气候湿润时,植物繁荣,湖水淡化,陆源有机质丰富。缺氧条件下的有机质降解主要是效率极低的发酵作用。有利于有机质保存。这种情形出现于岩芯段的下部,以较高TOC和较低SRI值为特征。 相似文献
19.
20.
Characterization of sediments in an abandoned mining area; a case study of Mansfeld region,Germany 总被引:1,自引:0,他引:1
Rainer?WennrichEmail author Jürgen?Mattusch Peter?Morgenstern Klaus?Freyer Hanns-Christian?Treutler Hans-Joachim?St?rk Lutz?Brüggemann Albrecht?Paschke Birgit?Daus Holger?Weiss 《Environmental Geology》2004,45(6):818-833
The distribution of selected heavy metals, including some radionuclides, metalloids and non-metals was determined in stream sediments in a region influenced by abandoned copper mining and ore processing activities. A considerable amount of the ore processing waste with a very complex composition and highly elevated concentrations of zinc, sulfur, lead, copper, arsenic, and a lot of other elements in the range between 100 and 1,000 mg/kg (Sb, Mn, Ni, Cr, Cd, Hg, and Ag) was piled up on mine dumps. The dispersion of the pollutants originating from this source and their environmental impact were investigated. Both, sediments and original waste material were studied to indicate the pathways and the mobilization behavior of different pollutants. For this purpose, the process of the elution of pollutants by application of different fractionation schemes was studied. The capabilities of different analytical techniques are shown for the analysis of solid samples (X-ray fluorescence spectrometry, Gamma-spectrometry) and liquid ones (ICP-atomic emission spectrometry, ICP-mass spectrometry and different techniques of atomic absorption). Additionally, the coupling of ion chromatography and ICP-MS detection was used to study the distribution of arsenic species in the sediment cores of a lake which acts as a natural sink for the region. 相似文献