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31.
Observations and samples from research submersible dives confirm that brines, crude oil, fluid mud, and gases are common seep
products. Through this mechanism a unique interplay of geochemical, geologic, and biological processes resulting in unusual
sea floor features ranging from carbonate-rich nodular sediments to mounds with tens of meters relief. Stable carbon isotopes
occluded in the carbonates provide a permanent imprint that links these authigenic carbonates to by-products of microbial
breakdown of crude oil and gas. Recent DSV ALVIN dives confirm that hydrocarbon seeps and their accompanying chemosynthetic
communities and authigenic carbonate mounds occur over the entire depth range of the slope. 相似文献
32.
Discussion on ‘relaxation method for pounding action between adjacent buildings at expansion joint’ by H. Takabatake,M. Yasui,Y. Nakagawa and A. Kishida 
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下载免费PDF全文 The paper under discussion presents a detailed study on the reduction of pounding force on buildings due to expansion joints being filled with rubber. From shake table experiments and numerical simulations, the authors of the paper concluded that the rubber can reduce the maximum pounding force and hence the pounding damage to buildings. However, the writers of this short communication observed some significant issues in the experimental results as well as the numerical simulations. These observations are presented and raise questions about the validity of the results and the subsequent conclusions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
33.
Shane C. Lishawa KathiJo Jankowski Pamela Geddes Daniel J. Larkin Andrew M. Monks Nancy C. Tuchman 《Aquatic Sciences - Research Across Boundaries》2014,76(4):483-495
Wetland ecosystems maintain and improve water quality through the process of denitrification, an increasingly important ecosystem service due to global N pollution. Invasive plants have the potential to disrupt denitrification by altering the environmental conditions that facilitate this process. Great Lakes coastal wetlands are experiencing widespread invasion by highly productive hybrid cattail with largely uncertain biogeochemical effects. Through field and controlled mesocosm studies, we sought to determine the effects of cattail invasion through time on denitrification rates and associated environmental factors in a Great Lakes coastal wetland. In the field, we found that cattail density correlated with increased denitrification and a suite of environmental and plant community characteristics and denitrification rates were positively correlated with NH4 +, sediment organic matter, reduced water levels, and cattail stand age. Through our controlled mesocosm study, we documented conditions 1- and 5-year following invasion and found that denitrification rates and soil organic matter increased in year 5, and cattail and year-since-invasion altered plant communities and soil NH4 +. Only a weak correlation between denitrification rates and cattail treatments was noted, however, owing to high replicate variability. Our results indicate that with increasing cattail residence time, one ecosystem service, biodiversity, was negatively impacted, while two other services, denitrification and sediment carbon accumulation, were enhanced. Thus, this highly invaded wetland still provides valuable services to aquatic ecosystems and to society. A holistic perspective is therefore critical when evaluating invasive species impacts in which negative impacts are weighed against other ecosystem services, which may be stimulated. 相似文献
34.
Profitability of fish farming can be undermined by a suite of biological constraints. Effects of these constraints on the biology of the animal, the functioning of a tissue, or the quality of the final filleted product can be detected with very sensitive hi-tech approaches, grouped by the term ‘-omics’. These -omics technologies further present powerful tools for the genetic selection of diverse traits and, as such, will contribute substantially to the future development of the aquaculture sector. Sustainability issues of importance to the industry, such as environmental impacts, use of therapeutants, fish health management and fishmeal replacement, can again be aided, at least in part, through the effective use of -omics technologies. It thus appears that -omics technologies may be a key tool for the responsible growth of intensive aquaculture in the 21st century. In this paper we review the current status of -omics technologies and the potential for application within the aquaculture industry. 相似文献