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61.
Social-ecological complexity challenges conservation-oriented interventions even in settings with a small number of actors and conflicts involved. This article examines the development and trajectory of King and Snow Crab fisheries in the Cape Horn Biosphere Reserve (BR), the highly remote but globally connected Southern tip of the Americas. The feasibility of the Chilean legal instrument of Marine Management Areas (MMA) is assessed as a tool for mitigating impacts of overfishing in the area. Examining the local fishers’ perspectives in complement to a context analysis we find that external management models such as the MMA are not suited to make Cape Horn fisheries sustainable. Instead, efforts should be dedicated to a continuous process of stakeholder collaboration for developing site-specific management concepts and structures. These should be embedded in the larger BR initiative. Considering the area's particular conditions, several recommendations for such a process are formulated. 相似文献
62.
Michael Edward Hohn 《Mathematical Geology》1979,11(6):611-626
A three-mode principal components method allows visualization of the structural or taxonomic relationships within three-way data tables. The fundamental model includes three sets of eigenvectors and a core matrix relating the principal components of each mode. Formal relationships between the method and the usual principal components formulation allow calculation of loadings and scores for each mode; taken with the core matrix, these provide a number of points of view in graphical analysis of three-mode data. The model compares favorably with alternative formulations in terms of simplicity of computation, generality, and symmetry of operation among the modes. An organic geochemical example illustrates the method. 相似文献
63.
The multivariate statistical method of Principal Components Analysis is used to classify gas chromatographic-mass spectrometric data. The specific examples comprise sterane and triterpane regions of GC-MS analyses of branched/cyclic fractions. The statistical model provides an objective analogue to visual comparison and classification of mass fragmentograms. Sources of experimental error influencing the statistical results include insufficient sample size, short integration times, and peak skewing. The method successfully groups samples of oils, oil sand, and polluted beach sand according to geographic origin: beach sand groups with type of crude spilled; laboratory biodegraded and untreated Nigerian crudes group together. Applications of three-mode Principal Components Analysis can range from study of geologic processes acting on organic compounds to classification of unknown pollutants. 相似文献
64.
Matthias Jonas Katharina Fleischmann Andrey V. Ganopolski Jaroslav Krabec Uta Sauer Krzysztof Olendrzyński Vladimir K. Petoukhov Roderick W. Shaw 《Climatic change》1996,34(3-4):479-512
This paper describes a methodology that combines the outputs of (1) the Integrated Model to Assess the Greenhouse Effect (IMAGE Version 1.0) of the Netherlands National Institute of Public Health and Environmental Protection (RIVM) (given a greenhouse gas emission policy, this model can estimate the effects such as global mean surface air temperature change for a wide variety of policies) and (2) ECHAM-1/LSG, the Global Circulation Model (GCM) of the Max-Planck Institute for Meteorology in Hamburg, Germany. The combination enables one to calculate grid point surface air temperature changes for different scenarios with a turnaround time that is much quicker than that for a GCM. The methodology is based upon a geographical pattern of the ratio of grid point temperature change to global mean values during a certain period of the simulation, as calculated by ECHAM-1/LSG for the 1990 Scenarios A and D of the Intergovernmental Panel on Climate Change (IPCC). A procedure, based upon signal-to noise ratios in the outputs, enabled us to estimate where we have confidence in the methodology; this is at about 23% to 83% of the total of 2,048 grid points, depending upon the scenario and the decade in the simulation. It was found that the methodology enabled IMAGE to provide useful estimates of the GCM-predicted grid point temperature changes. These estimates were within 0.5K (0.25K) throughout the 100 years of a given simulation for at least 79% (74%) of the grid points where we are confident in applying the methodology. The temperature ratio pattern from Scenario A enabled IMAGE to provide useful estimates of temperature change within 0.5K (0.25K) in Scenario D for at least 88% (68%) of the grid points where we have confidence; indicating that the methodology is transferable to other scenarios. Tests with the Geophysical Fluid Dynamics Laboratory GCM indicated, however, that a temperature ratio pattern may have to be developed for each GCM. The methodology, using a temperature ratio pattern from the 1990 IPCC Scenario A and involving IMAGE, gave gridded surface air temperature patterns for the 1992 IPCC radiative-forcing Scenarios C and E and the RIVM emission Scenario B; none of these scenarios has been simulated by ECHAM-1/LSG. The simulations reflect the uncertainty range of a future warming.The work reported by the authors was carried out during their stay at the project Forestry and Climate Change of the International Institute for Applied Systems Analysis, Laxenburg, Austria. 相似文献
65.
Fatty acids extracted from six fruit of Nyssa fissilis from the Early Tertiary Brandon Lignite, Vermont, include mainly palmitic, palmitoleic, stearic, and oleic acids and a number of probable branched chain acids. Four unidentified ‘round fruit’ from the lignite contained the same acids in predominance. The two taxa were chemically indistinguishable because of wide intraspecific variation in percentage of each n-fatty acid present. ‘Fingerprint’ chromatograms of non-aromatic hydrocarbon extracts from two distinct taxa of fruit from an Eocene clay of Tennessee also showed no consistent interspecific differences. We conclude that degradation and removal of the seed food reserves and introduction of extraneous lipids limits the utility of fatty acids and hydrocarbons in chemosystematic study of fossil fruits at the species and genus levels. 相似文献
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68.
Claudia Sandig Uta Sauer Karin Bräuer Ulrich Serfling Claudia Schütze 《Environmental Earth Sciences》2014,72(5):1421-1434
Our study at this natural analog site contributes to the evaluation of methods within a hierarchical monitoring concept suited for the control of CO2 degassing. It supports the development of an effective monitoring concept for geological CO2 storage sites—carbon capture and storage as one of the pillars of the European climate change efforts. This study presents results of comprehensive investigations along a 500-m long profile within the Hartou?ov (Czech Republic) natural CO2 degassing site and gives structural information about the subsurface and interaction processes in relation to parameters measured. Measurements of CO2 concentrations and investigation of the subsurface using electrical resistivity tomography and self-potential methods provide information about subsurface properties. For their successful application it is necessary to take seasonal variations (e.g., soil moisture, temperature, meteorological conditions) into consideration due to their influence on these parameters. Locations of high CO2 concentration in shallow depths are related to positive self-potential anomalies, low soil moistures and high resistivity distributions, as well as high δ13C values and increased radon concentrations. CO2 ascends from deep geological sources via preferential pathways and accumulates in coarser sediments. Repetition of measurements (which includes the effects of seasonal variations) revealed similar trends and allows us to identify a clear, prominent zone of anomalous values. Coarser unconsolidated sedimentary layers are beneficial for the accumulation of CO2 gas. The distribution of such shallow geological structures needs to be considered as a significant environmental risk potential whenever sudden degassing of large gas volumes occurs. 相似文献