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Mapping the seabed along the Norwegian coast is costly and time consuming. Hence, finding a modeling method to separate rocky seabed from other substrate types will provide digital maps that may be used to develop cost-effective sampling designs to predict species and habitat distribution. Our approach was to use geophysical data that were quantitative and objectively defined, generalized additive models (GAMs), and Akaike information criterion (AIC) to develop statistical models and select among them. We found that slope, terrain curvature, wave exposure, and depth predicted rocky seabed occurrence with a high degree of certainty.  相似文献   
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Cycling plays an important role in low-carbon transitions. Around the globe, cities are constructing bicycle infrastructure. The city of Copenhagen has a bicycle-friendly infrastructure celebrated for its fine-meshed network. This study documents the spatio-temporal development of Copenhagen’s bicycle infrastructure and explores how the development corresponds to other processes of urban transformation. The study builds on historical maps of bicycle infrastructure that are digitised into geographical information, which allows for a comprehensive analysis of the formation of the network. In search for identifying drivers, the study analyses the city’s spatial growth pattern, migration pattern, development of road network and changes in the transport culture. Analyses reveal that the bicycle infrastructure expanded at a relatively constant pace during distinct periods of urban transformation, including periods when the city suffered from spatial, economic and demographic decline, and dominance of car traffic. By discussing reasons and demands for constructing bicycle infrastructure, the study identifies four distinct periods in which bicycle infrastructure was constructed to enhance comfort and safety (first cycling city); the flow for cars (car city); urban liveability for soft transport (liveable city); and, finally, to improve the flow for cyclists as part a strategic re-design of urban space (liveable cycling city).  相似文献   
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Transport of ballast water is one major factor in the transmission of aquatic organisms, including pathogenic bacteria. The IMO-guidelines of the Convention for the Control and Management of Ships' Ballast Water and Sediments, states that ships are to discharge <1 CFU per 100 ml ballast water of toxigenic Vibrio cholerae, emphasizing the need to establish test methods. To our knowledge, there are no methods sensitive and rapid enough available for cholera surveillance of ballast water. In this study real-time PCR and NASBA methods have been evaluated to specifically detect 1 CFU/100ml of V. cholerae in ballast water. Ballast water samples spiked with V. cholerae cells were filtered and enriched in alkaline peptone water before PCR or NASBA detection. The entire method, including sample preparation and analysis was performed within 7 h, and has the potential to be used for analysis of ballast water for inspection and enforcement control.  相似文献   
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The paper addresses the dynamic relationship between the human use of land and alterations in the biophysical environment, demographic pressure or socio-economic conditions. An empirical study from the Sahelian zone in northern Burkina Faso illustrates the dynamics of cultivation pattern at the village level and the changing priorities given to different landscape units over time. Field measurements, aerial photos and satellite images from seven successive years provide information on land use pattern changes from 1945 to 1995. A household survey illustrates how socio-economic and cultural parameters enable and constrain land use strategies at the farm level.  相似文献   
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Sugar kelp (Saccharina latissima) forests have an important ecological function in the coastal zone, as they inhabit a high number and a specific composition of fauna. In 2002, a large-scale disappearance of sugar kelp was observed in Skagerrak and parts of the south-western coast of Norway, and the perennial sugar kelp forests were replaced by opportunistic and ephemeral filamentous algae. For management purposes, including identifying areas for restoration initiatives, maps of where sugar kelp forests are supposed to be found and where and under what conditions they have disappeared are needed. Based on modelled and field-measured geophysical variables and presence/absence/loss data of sugar kelp, we therefore developed spatial predictive probability models (i.e. maps) for sugar kelp potential distribution under natural conditions and areas of kelp loss. The influence of geophysical factors was analysed using generalized additive models (GAMs). Using the Akaike Information Criterion (AIC) for model selection, we found that wave exposure, depth, light exposure and slope best explained the potential distribution of sugar kelp. Areas of sugar kelp disappearance were identified by the combined effect of wave and light exposure. These models were developed into maps presented to the managers.  相似文献   
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Geografisk Tidsskrift—Danish Journal of Geography 110(2):297–314, 2010

The Inglefield Land Archaeology Project undertook archaeological survey of three areas of Foulke Fjord in 2006, during which 639 archaeological features were recorded, exclusive of the large Reindeer Point Longhouse site (Darwent et al., 2008). Basedon comparisons with surveys completed in Eastern Inglefield Land (Darwent et al., 2007), the density of features in Foulke Fjord substantially exceeded those from other regions of Inglefield Land. The most parsimonious explanation for the higher occurrence of features in this region is the presence of little auk colonies on the scree slopes of the inner fjords. These birds, which roost in the millions, served as a reliable summer food source, but their feces likely provided enrichment for the local ecosystem, increasing the numbers of terrestrial and marine fauna in the region. Based on excavations at Iita (Etah) and densities of features in the fiord, Foulke Fjord appears to have been continually occupied throughout the Thule-historic period (A.D. 1250–1953), and during the previous Late Dorset period (ca. A.D. 800–1250). However, features associated with the early Paleoeskimo period (2500–500 B.C.) are located only at the outer margins of the fjord.  相似文献   
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Fatty acid profiles and lipid biomarkers from 20 harp seals were used to investigate the foraging ecology of harp seals and the transfer of energy through the Franz Josef Land-Novaya Zemlya food chain. High levels of the Calanus fatty acid trophic markers (FATMs) 20:1(n-9) (mean 14.6%) and 22:1(n-11) (mean 6.5%), together with the typical dinoflagellate FATMs 22:6(n-3) (mean 6.5%) and C18PUFA (mean 5.5%), were found in blubber samples. Based on the analyses of the fatty acid profiles separated by principal component analysis, we confirmed the importance of polar cod ( Boreogadus saida ) and the pelagic amphipod Themisto libellula in the diet of harp seal. The high levels of 22:6(n-3), C18PUFA and C20 and C22 FATMs show that the harp seal lipids mainly originate from dinoflagellates consumed by Calanus copepods.  相似文献   
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