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151.
Detailed information on vertical variations in hydraulic conductivity (K) is essential to describe the dynamics of groundwater movement at contaminated sites or as input data used for modeling. K values in high vertical resolution should be determined because K tends to be more continuous in the horizontal than in the vertical direction. To determine K in shallow unconsolidated sediments and in the vertical direction, the recently developed direct-push injection logger can be used. The information obtained by this method serves as a proxy for K and has to be calibrated to obtain quantitative K values of measured vertical profiles. In this study, we performed direct-push soil sampling, sieve analyses and direct-push slug tests to obtain K values in vertical high resolution. Using the results of direct-push slug tests, quantitative K values obtained by the direct-push injection logger could be determined successfully. The results of sieve analyses provided lower accordance with the logs due to the inherent limitations of the sieving method. 相似文献
152.
153.
Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
154.
Single-core and to a certain extent multi-core lead-rubber bearings have been extensively used in seismic isolation. Yet their behavior is not well understood and experimentation is required to obtain their mechanical properties. A recently developed and validated theory contributed to the understanding of the effects of heating of the lead core on the characteristic strength and ability to dissipate energy of these bearings. Additional results on the theory of heating of lead-rubber bearings are presented in this paper, including readily useable data on the rise of temperature in the steel shim and end plates of these bearings. The results may be used in the assessment of the validity of the theory of lead core heating in single and multi-core lead-rubber bearings and in recently developed multi-core lead-rubber dampers. Examples are presented (including some experimental data) to illustrate the application of the theory. The utility of the presented theory is to reduce the requirements for physical testing of lead-rubber bearings and dampers. 相似文献
155.
Chapalain Marion Verney Romaric Fettweis Michael Jacquet Matthias Le Berre David Le Hir Pierre 《Ocean Dynamics》2019,69(1):59-81
Ocean Dynamics - Suspended particulate matters (SPM) in coastal waters were investigated with an approach combining suspended particulate matter concentrations (SPMCs) measured by an optical... 相似文献
156.
Diet restriction induced autophagy: a lysosomal protective system against oxidative- and pollutant-stress and cell injury 总被引:1,自引:0,他引:1
Moore MN 《Marine environmental research》2004,58(2-5):603-607
Nutrient deprivation or dietary restriction (DR) confers protection against ageing and stress in many animals and induced lysosomal autophagy is part of this mechanism. The effects of dietary restriction on the toxicity of copper and the polycyclic aromatic hydrocarbon phenanthrene have been investigated in the common marine mussel Mytilus edulis. The findings show that DR-induced autophagy facilitates the recovery of the digestive gland (i.e., molluscan liver analogue) from cell injury caused by both copper and phenanthrene. It is inferred that DR-induced autophagy and lysosomal proteolysis results in improved cellular "housekeeping" through the more efficient removal of oxidatively and pollutant damaged proteins (e.g., protein carbonyls, protein adducts, etc.) and that this contributes to stress resistance. 相似文献
157.
Microzooplankton production in the oceans 总被引:7,自引:0,他引:7
158.
Here, we describe a methodology for quantifying the spawning habitat of īnanga (Galaxias maculatus), a protected native fish species. Our approach is demonstrated with a survey of the Heathcote/ōpāwaho following the Canterbury earthquakes that produced unexpected findings. Spawning habitat was detected over a 2.5?km reach and the area occupied by spawning sites (75m2) was much larger than in previous records (ca.?21m2). Sites dominated by the invasive Phalaris arundinaceae were found to support high egg numbers. Spawning has not previously been recorded on this species and it is identified in the literature as a threat to spawning habitat. Considerable spatio-temporal variation was also detected in the location of spawning sites and pattern of egg production. Together, these aspects illustrate the need for a comprehensive survey methodology to reliably quantify spawning habitat. The Heathcote/ōpāwaho example shows the utility of our census approach for achieving this, and supporting habitat conservation objectives. 相似文献
159.
Macrofauna Communities in the Eastern Mediterranean Deep Sea 总被引:1,自引:0,他引:1
Abstract. During two expeditions with RV ‘Meteor’ in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension‐feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large‐scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea. 相似文献
160.
The live reef fish for food trade is a highly significant fishery that provides income for many coastal communities in the Asia-Pacific region but faces challenges relating to sustainability. This paper draws attention to the large gaps that exist between policy and practice in the live reef fish for food trade in Palawan, Philippines. While many policies have been introduced over many years, effective implementation remains a challenge. We show how the implementation of successive sets of policies has been hindered by three broadly inter-related features of the local social landscape: the capacity of government institutions and legal frameworks to implement regulations, the distinctive culture of fisheries governance in the Philippines, and the perspectives and practices of local fishers themselves. By focusing on the gaps between policy and practice, we highlight the ongoing need to examine more explicitly the ways in which local contexts shape the effectiveness of implementation, enforcement and policy more generally. 相似文献