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排序方式: 共有446条查询结果,搜索用时 15 毫秒
71.
Dirk Erpenbeck John N. A. Hooper Isabelle Bonnard Patricia Sutcliffe Mayuri Chandra Pierre Perio Carsten Wolff Bernard Banaigs Gert W?rheide Cécile Debitus Sylvain Petek 《Marine Biology》2012,159(5):1119-1127
Sponges of the family Dysideidae (Dictyoceratida) are renowned for their diversity of secondary metabolites, and its genus Lamellodysidea, particularly Lamellodysidea herbacea, is the most studied taxon biochemically. Despite its importance, the taxonomic status of L. herbacea—whether it is a distinct species or a species complex—has never been assessed. Recent biochemical profiling revealed anti-plasmodial activity of brominated compounds in Lamellodysidea of the Pacific. Here, we present a comparative chemotaxonomic and molecular analysis of selected Dysideidae from the Pacific and the Indian Ocean (New Caledonia, Great Barrier Reef, Fiji, Mayotte, Guam, Palau). We investigated the phylogenetic relationships between the populations and assessed their bioactive (PBDE) compounds in order to unravel the taxonomic status of this commercially important group of sponges and assessed patterns of dispersal and biochemical variation. The molecular phylogeny was based on the internal transcribed ribosomal spacer and compared against a PBDE phylogeny for several specimens. Molecular data revealed a diversity of Indo-Pacific L. herbacea populations, also reflected by different PBDE compound profiles. Molecular and biochemical data also revealed a Lamellodysidea species new to science. Several specimens misidentified as Lamellodysidea were detected based on their position on different clades in the molecular phylogeny and their production of different halogenated compounds (brominated vs. chlorinated). The direct comparison of molecular and biochemical data also provided evidence for the occurrence of a host switch event and support for the theory that abiotic factors, such as sedimentation, affect the chemical constituents produced in L. herbacea. 相似文献
72.
Aline Chiabai Dirk R��bbelke Lisa Maurer 《Environment, Development and Sustainability》2013,15(1):81-100
Whether information and communication technology (ICT) constitutes a threat or a cure to environment??s deterioration is controversially discussed. Empirical evidence on the impacts of ICT is rare, so that generalizable lessons can hardly be drawn. This study provides empirical results on the role of ICT in research for environmental sustainability, but instead of ascertaining the impact of ICT on environmental protection, we conduct an analysis of the use of ICT in sustainability research. We assess the preferences of experts in different thematic sustainability fields for applying ICT tools, and we investigate ways to improve the application of these tools in order to augment their returns with respect to environmental protection research. This analysis is based on a set of surveys that were administered to international experts to evaluate the importance of ICT in environmental sustainability research and the research demands in key environmental sectors, such as climate change, natural resources, energy and biodiversity. The methodological framework is built on the analysis of users?? preferences for future developments in ICT tools using stated preferences techniques. Overall results suggest that ICT tools need to be developed in specific contexts, taking into account users?? needs and expectations. Our analysis shows that the use of ICT in environmental research is of great importance in the scientific community, but it can also play a crucial role in the policy context. 相似文献
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Weise Katrin Kurth Thomas Politowski Irina Winkelmann Carola Schäffer Andreas Kretschmar Susanne Berendonk Thomas Ulrich Jungmann Dirk 《Environmental science and pollution research international》2022,29(18):26706-26725
Environmental Science and Pollution Research - Although the development and application of nanomaterials is a growing industry, little data is available on the ecotoxicological effects on aquatic... 相似文献
75.
Villy Christensen Carl J. Walters Robert Ahrens Jacqueline Alder Joe Buszowski Line Bang Christensen William W.L. Cheung John Dunne Rainer Froese Vasiliki Karpouzi Kristin Kaschner Kelly Kearney Sherman Lai Vicki Lam Maria L.D. Palomares Aja Peters-Mason Chiara Piroddi Jorge L. Sarmiento Jeroen Steenbeek Rashid Sumaila Reg Watson Dirk Zeller Daniel Pauly 《Ecological modelling》2009
We present a new methodology for database-driven ecosystem model generation and apply the methodology to the world's 66 currently defined Large Marine Ecosystems. The method relies on a large number of spatial and temporal databases, including FishBase, SeaLifeBase, as well as several other databases developed notably as part of the Sea Around Us project. The models are formulated using the freely available Ecopath with Ecosim (EwE) modeling approach and software. We tune the models by fitting to available time series data, but recognize that the models represent only a first-generation of database-driven ecosystem models. We use the models to obtain a first estimate of fish biomass in the world's LMEs. The biggest hurdles at present to further model development and validation are insufficient time series trend information, and data on spatial fishing effort. 相似文献
76.
Bernhard Rappenglück Heinrich Reitmayer Peter Fabian 《Environmental science and pollution research international》2000,7(4):211-218
Measurements of nitrogen dioxide, ozone and, for the first time, on-line, nonmethane hydrocarbons with a quasicontinuous gaschromatographic/flame ionization technique were performed on a manned hydrogen-gas balloon platform. A cycle time of 10 min allowed the determination of nonmethane hydrocarbons in the carbon number range of C4-C10 with a detection limit of 10 pptv. In addition, meteorological parameters (atmospheric pressure, temperature, humidity) along with GPS-data (global positioning system) was accomplished during the balloon flights. Balloon measurements of trace compounds provide valuable information about photochemical processes in the boundary layer since gas ballooning offers the only technique that stays in the same air parcel along Langrangian trajectories. In addition, gas ballooning represents a unique tool to elucidate micrometeorological observations such as atmospheric stability oscillations and local wind fields. 相似文献
77.
78.
Improvements on Flood Alleviation in Germany: Lessons Learned from the Elbe Flood in August 2002 总被引:1,自引:0,他引:1
The increase in damage due to natural disasters is directly related to the number of people who live and work in hazardous
areas and continuously accumulate assets. Therefore, land use planning authorities have to manage effectively the establishment
and development of settlements in flood-prone areas in order to avoid the further increase of vulnerable assets. Germany faced
major destruction during the flood in August 2002 in the Elbe and Danube catchments, and many changes have been suggested
in the existing German water and planning regulations. This article presents some findings of a “Lessons Learned” study that
was carried out in the aftermath of the flood and discusses the following topics: 1) the establishment of comprehensive hazard
maps and flood protection concepts, 2) the harmonization of regulations of flood protection at the federal level, 3) the communication
of the flood hazard and awareness strategies, and 4) how damage potential can be minimized through measures of area precaution
such as resettlement and risk-adapted land use. Although attempts towards a coordinated and harmonized creation of flood hazard
maps and concepts have been made, there is still no uniform strategy at all planning levels and for all states (Lae
nder) of the Federal Republic of Germany. The development and communication of possible mitigation strategies for “unthinkable
extreme events” beyond the common safety level of a 100-year flood are needed. In order to establish a sustainable and integrated
flood risk management, interdisciplinary and catchment-based approaches are needed. 相似文献
79.
80.