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Conservation policies have changed over time in response to changes in human and ecological drivers. The impacts of climate (and other) concurrent changes prompt consideration of further iterations for both conservation means and objectives. In this paper we bring together previous disparate literatures and apply them to the question of how to adapt conservation polices to suit an era of climate change impacts. Our approach is based on two assertions: (i) that the integration of specific natural and social science insights is essential for understanding and effectively responding to this challenge, and (ii) that in addition to adaptive conservation means (strategies), attention needs to be given to considering adaptive conservation objectives. Specifically, we convert a core set of natural and social science insights into analytical tools known as heuristics or rules of thumb. We then use the heuristics as a basis to offer a list of preliminary propositions that can help inform the development of new means and objectives. The propositions address key considerations including recalibrating management objectives, the role of disturbance in facilitating ecological transitions, and overarching topics relating to governance. The propositions are speculative, and so intended only to outline potential avenues for further empirical research and subsequent refinement. In the spirit of adaptation, we expect and welcome their revision.  相似文献   
2.
Food web interactions and the response of Pacific salmon to physical processes in the North Pacific Ocean over interannual and interdecadal timescales are explored using naturally occurring stable isotope ratios of carbon (13C/12C) and nitrogen (15N/14N). Stable isotope analyses of five species of sexually mature North Pacific salmon from Alaska (Oncorhynchus spp.) cluster into three groups: chinook salmon (O. tshawytscha) have the highest values, followed by coho (O. kisutch), with chum (O. keta), sockeye (O. nerka), and pink (O. gorbuscha) together having the lowest values. Although detailed isotopic data on salmon prey are lacking, there are limited data on relevant prey items from areas in which they are found in high abundance. These data suggest that the characteristics of the sockeye, pink and chum we have analyzed are compatible with their diets including open ocean squid and zooplankton, which are in general agreement with stomach content analyses. Isotope relationships between muscle and scale show consistent relationships for both δ13C (R2=0.98) and δ15N (R2=0.90). Thus, scales, which have been routinely archived for many systems, can be used for retrospective analyses. Archived sockeye salmon scales spanning 1966–1999 from Red Lake, Kodiak Island, Alaska were analyzed for their stable isotope ratios of carbon and nitrogen. The δ15N record displays a decreasing trend of ˜3‰ from 1969–1982 and an increasing trend of ˜3‰ from 1982–1992, while the variations in δ13C are relatively minor. These trends may result from factors such as shifts in trophic level of feeding and/or feeding location, or may originate at the base of the food web via changes in processes such as nutrient cycling or primary productivity. Detailed studies on prey isotopic variability and its controls are needed to distinguish between these factors, and thus to improve the use of stable isotope analysis as a tool to learn more about present and past ecosystem change in the North Pacific and its relation to climatic change.  相似文献   
3.
Adapting conservation policy to the impacts of climate change has emerged as a central and unresolved challenge. In this paper, we report on the results of 21 in-depth interviews with biodiversity and climate change adaptation experts on their views of the implications of climate change for conservation policy. We find a diversity of views across a set of topics that included: changing conservation objectives, conservation triage and its criteria, increased management interventions in protected areas, the role of uncertainty in decision-making, and evolving standards of conservation success. Notably, our findings reveal active consideration among experts with some more controversial elements of policy adaptation (including the role of disturbance in facilitating species transitions, and changing standards of conservation success), despite a comparative silence on these topics in the published literature. Implications of these findings are discussed with respect to: (a) identifying future research and integration needs and (b) providing insight into the process of policy adaptation in the context of biodiversity conservation.  相似文献   
4.
This paper aims to analyze a fisheries co-management regime in Brazil. The Forum of the Patos Lagoon, a collaborative partnership among communities, governmental and non-governmental organizations, was established to move fisheries management toward a negotiation-style decision processes. We find that while many successes are evident including the delegation of decision power, greater protection of artisanal fisheries, and greater legitimacy assigned the Forum as a decision-making body, several problems remain. These include conflicting institutional arrangements; minimal recognition of local fishers’ interests as concerns rules established; and less than optimal participation of fishers in the Forum. The paper closes with multiple suggestions for improvements of this co-management regime.  相似文献   
5.
Experiments on partial melting of mantle lherzolite have been realized at 0.6 and 1.0 GPa and the chemical compositional variations of melts during different melting stages have been first discussed. The results show that the trends of variations in SiO2, CaO, Al2O3, Na2O and TiO2 are different at different melting stages. The melts produced at lower pressure are richer in SiO2 than those at higher pressure. The mantle-derived silica-rich fluids (silicate melts) are polygenetic, but the basic and intermediate-acid silicate melts in mantle peridotite xenoliths from the same host rocks, which have equivalent contents of volatile and alkali components and different contents of other components, should result from in-situ (low-degree) partial melting of mantle peridotite under different conditions (e.g. at different depths, with introduction of C-O-H fluids or in the presence of metasomatic minerals). The intermediate-acid melts may be the result of partial melting (at lower pressure) Opx + Sp + K-Na-rich f  相似文献   
6.
Summary Anorogenic granites are principally associated with alkaline ring complexes or anorthositic suites. Compositional relationships in the granites may be largely the result of variable compositions of fluid phases present during the initial melting and/or later evolution. For example, the negative K2O-SiO2 relationships in granites associated with alkaline rocks is consistent with: (1) evolution of the initial melts in a CO2-rich environment, which causes the product of incongruent melting of biotite to be a prominent component of the derived magmas; and/or (2) crystallization of the granites in a CO2-rich environment, which causes a residual liquid to be rich in biotite component. Limited evidence indicates that granites evolved in fluorine-rich environments are enriched in Na and may have negative relationships between Na2O and SiO2. Fluorine-rich environments may be more characteristic of the silicic rocks in rapakivi-granit e/anorthosite complexes than of granites in alkaline suites.
Fluida von anorogenen Graniten: Eine erste, abschätzende Studie
Zusammenfassung Anorogene Granite sind prinzipiell mit alkalischen Ringkomplexen oder AnorthositSerien assoziiert. Die spezielle Zusammensetzung dieser Granite resultiert vermutlich hauptsächlich aus der variablen Zusammensetzung der während des initialen Schmelzprozesses und/oder späteren magmatischen Evolution vorhandenen fluiden Phase. Zum Beispiel geht die negative Korrelation zwischen K2O und SiO2 in Graniten, die mit alkalinen Gesteinen assoziiert sind, konform mit 1) der Entwicklung der Initialschmelze in einem CO2-reichen Milieu, wodurch das Produkt des inkongruenten Schmelzens von Biotit als Komponente im Magma dominiert, und/oder 2) der Kristallisation der Granite in einem CO2-reichen Milieu, das wiederum eine biotitreiche Residualschmelze hervorruft. Limitierte Hinweise deuten an, daß Granite, die in einem fluorreichen Milieuentstehen, an Na angereichert sind und eine negative Korrelation zwischen Na2O und SiO2 zeigen. Fluorreiches Milieu ist vermutlich für die sauren Gesteine innerhalb von Rapakivi-Granit/Anorthosit-Komplexen eher charakteristisch als für Granite in alkalischen Serien.
  相似文献   
7.
This paper presents an assessment of SARAL/AltiKa satellite altimeter for the monitoring of a tropical western boundary current in the south-western Pacific Ocean: the East Caledonian Current. We compare surface geostrophic current estimates obtained from two versions of AltiKa along-track sea level height (AVISO 1 Hz and PEACHI 40 Hz) with two kinds of dedicated in situ datasets harvested along the satellite ground tracks: one deep-ocean current-meter mooring deployed in the core of the boundary current and five glider transects. It is concluded that the AltiKa-derived current successfully captures the velocity of the boundary current, with a standard error of 11 cm/s with respect to the in situ data. It also appears important to reference AltiKa sea level anomaly to the latest mean dynamic topography available in our area. Doing so, Ka-band altimetry provides a satisfactory representation of the western boundary current. Thereby, it usefully contributes to observing its variability in such a remote and under-observed ocean region. However, the rather long repeat period of SARAL (35 days) in comparison to the high frequency variability seen in the flow velocity of the boundary current calls for a combined use of SARAL with the other satellite altimetry missions.  相似文献   
8.
The Pyrenees is a young mountain belt formed as part of the larger Alpine collision zone. This excursion explores the development of the Pyrenean Mountain Belt in southern France, from its early extensional phase in the mid‐Cretaceous and subsequent collisional phase, through its uplift and erosion in the Late Cretaceous and again in the Eocene, which led to the development of the Aquitaine‐Languedoc foreland basin. One of the complexities of the Pyrenean Belt is that thrusting, uplift and erosion during the Pyrenean orogeny exposed older Variscan basement rocks in the central core of the mountains, rocks which were metamorphosed during an earlier event in the late Carboniferous. Thus, this orogenic belt also tells the story of an earlier collision between Laurussia in the north and Gondwana in the south at c. 300 Ma, prior to the onset of the Pyrenean events at c. 100 Ma. Here we seek to unravel these two separate orogenic stories.  相似文献   
9.
流体包裹体研究的进展和方向   总被引:45,自引:3,他引:42  
卢焕章  郭迪江 《地质论评》2000,46(4):385-392
国外近十年来,在流体包裹体研究方面取得很大进展,除了在地质年会上有许多成果报道之外,专业会议更是每年召开一次(指北美流体包裹体会议和欧州体包裹体会议),报道了大量最新的有关包裹体的研究成果。本文将从4个方面评述国外近年来流体包裹体的研究进展:即人工流体包裹体及P-T-V-X属性;流体包裹体的成分分析和年代学;流体包裹体在金矿及其他矿床研究中的应用和利用流体包裹体寻找石油。  相似文献   
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