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171.
Peter F. Sale Tundi Agardy Cameron H. Ainsworth Blake E. Feist Johann D. Bell Patrick Christie Ove Hoegh-Guldberg Peter J. Mumby David A. Feary Megan I. Saunders Tim M. Daw Simon J. Foale Phillip S. Levin Kenyon C. Lindeman Kai Lorenzen Robert S. Pomeroy Edward H. Allison R.H. Bradbury Jennifer Corrin Alasdair J. Edwards David O. Obura Yvonne J. Sadovy de Mitcheson Melita A. Samoilys Charles R.C. Sheppard 《Marine pollution bulletin》2014
Over 1.3 billion people live on tropical coasts, primarily in developing countries. Many depend on adjacent coastal seas for food, and livelihoods. We show how trends in demography and in several local and global anthropogenic stressors are progressively degrading capacity of coastal waters to sustain these people. Far more effective approaches to environmental management are needed if the loss in provision of ecosystem goods and services is to be stemmed. We propose expanded use of marine spatial planning as a framework for more effective, pragmatic management based on ocean zones to accommodate conflicting uses. This would force the holistic, regional-scale reconciliation of food security, livelihoods, and conservation that is needed. Transforming how countries manage coastal resources will require major change in policy and politics, implemented with sufficient flexibility to accommodate societal variations. Achieving this change is a major challenge – one that affects the lives of one fifth of humanity. 相似文献
172.
Richard L. Reynolds Jessica S. Mordecai Joseph G. Rosenbaum Michael E. Ketterer Megan K. Walsh Katrina A. Moser 《Journal of Paleolimnology》2010,44(1):161-175
Sediments in Marshall and Hidden Lakes in the Uinta Mountains of northeastern Utah contain records of atmospheric mineral-dust
deposition as revealed by differences in mineralogy and geochemistry of lake sediments relative to Precambrian clastic rocks
in the watersheds. In cores spanning more than a thousand years, the largest changes in composition occurred within the past
approximately 140 years. Many elements associated with ore deposits (Ag, As, Bi, Cd, Cu, In, Mo, Pb, S, Sb, Sn, and Te) increase
in the lake sediments above depths that correspond to about AD 1870. Sources of these metals from mining districts to the
west of the Uinta Mountains are suggested by (1) the absence of mining and smelting of these metals in the Uinta Mountains,
and (2) lower concentrations of most of these elements in post-settlement sediments of Hidden Lake than in those of Marshall
Lake, which is closer to areas of mining and the densely urbanized part of north-central Utah that is termed the Wasatch Front,
and (3) correspondence of Pb isotopic compositions in the sediments with isotopic composition of ores likely to have been
smelted in the Wasatch Front. A major source of Cu in lake sediments may have been the Bingham Canyon open-pit mine 110 km
west of Marshall Lake. Numerous other sources of metals beyond the Wasatch Front are likely, on the basis of the widespread
increases of industrial activities in western United States since about AD 1900. In sediment deposited since ca. AD 1945,
as estimated using 239+240Pu activities, increases in concentrations of Mn, Fe, S, and some other redox-sensitive metals may result partly from diagenesis
related to changes in redox. However, our results indicate that these elemental increases are also related to atmospheric
inputs on the basis of their large increases that are nearly coincident with abrupt increases in silt-sized, titanium-bearing
detrital magnetite. Such magnetite is interpreted as a component of atmospheric dust, because it is absent in catchment bedrock.
Enrichment of P in sediments deposited after ca. AD 1950 appears to be caused largely by atmospheric inputs, perhaps from
agricultural fertilizer along with magnetite-bearing soil. 相似文献
173.
Patricia?A.?TesterEmail author Sabrina?M.?Varnam Mary?E.?Culver David?L.?Eslinger Richard?P.?Stumpf Robert?N.?Swift James?K.?Yungel Megan?D.?Black R.?Wayne?Litaker 《Estuaries and Coasts》2003,26(5):1353-1364
Airborne laser-induced fluorescence measurements were used to detect and monitor ecosystem wide changes in the distribution
and concentration of chlorophyll biomass and colored dissolved organic matter in the Pamlico-Albemarle Sound system, North
Carolina, U.S., following massive flooding caused by a series of three hurricanes in the late summer of 1999. These high-resolution
data provided a significantly more detailed representation of the overall changes occurring in the system than could have
been achieved by synoptic sampling from any other platform. The response time for the distribution of chlorophyll biomass
to resume pre-flood conditions was used as a measure of ecosystem stability. Chlorophyll biomass patterns were reestablished
within four mo of the flooding, whereas higher chlorophylla biomass concentrations persisted for approximately 6 mo. The primary trophic level in the Pamlico-Albemarle Sound system
returned to equilibrium in less than a year of a major perturbation. 相似文献
174.
175.
Megan Ceronsky Cameron Hepburn Michael Obersteiner Yoshiki Yamagata 《Climate Policy》2013,13(4):347-357
Abstract Kagan (2002) argues that the different responses of Europeans and Americans to major strategic and international challenges is not simply due to differences in the current administrations, but rather results from (i) a power gap and (ii) differing ideologies. This article applies Kagan's theory to climate policy, employing terrorism policy as a point of comparison. We argue that the power gap between Europe and America is unable to explain the differences in climate policy. In contrast, the ideology gap may indeed have some explanatory value. Furthermore, we argue that one additional feature is critical—the costs and benefits imposed by climate change and terrorism prevention, and the process by which such costs and benefits are evaluated, differ between America and Europe. 相似文献
176.
Nonnative species cause economic and ecological impacts in habitats they invade, but there is little information on how they spread and become abundant. This is especially true for nonnative species in native Zostera marina eelgrass beds in coastal British Columbia, Canada, which play a vital role in estuarine ecosystems. We tested how nonnative species richness and abundance were related to both arrival vectors and environmental factors in northeast Pacific eelgrass. Using correlation tests and generalized linear models, we examined how nonnative macroinvertebrates (benthic, epifaunal, and large mobile) and some algae species were related to arrival vectors (shipping and aquaculture) and environmental factors (climate variables, human population density, and native richness and abundance). We found 12 nonnative species, 50 % with known negative impacts within eelgrass habitats. For benthic organisms, both nonnative richness and abundance were strongly correlated with shellfish aquaculture activities, and not with shipping activity. For epifaunal nonnative richness and abundance, neither vector was significantly correlated. Climate (temperature and salinity) helped explain nonnative richness but not abundance; there was no relationship of nonnative richness or abundance to native species richness and abundance or population density. Results suggest that aquaculture activities are responsible for many primary introductions of benthic nonnative species, and that temperature and salinity tolerances are responsible for post-introduction invasion success. While aquaculture and shipping vectors are becoming increasingly regulated to prevent further international spread of nonnative species, it will be important when managing nonnatives to consider secondary spread from intraregional transport through local shellfish aquaculture and shipping. 相似文献
177.
178.
Thin sections from 44 sherds representing eight prehistoric sites on four islands (Barbuda, Montserrat, Anguilla, St. Martin) in the northern Lesser Antilles (West Indies) were examined using a petrographic microscope. Point counting distinguished three temper associations: (1) exclusively volcanic,(2) volcanic and carbonate, and (3) volcanic, carbonate, and grog. Exclusively volcanic or dominantly volcanic (with low carbonate) temper associations occur in all Saladoid and many post-Saladoid sherds, with plagioclase feld-spar and volcanic rock fragments being most abundant. Thin sections with significant carbonate content or with grog were restricted to post-Saladoid sherds from Barbuda and to a lesser extent Anguilla. the presence of volcanic grains in sherds from the limestone islands of Barbuda and Anguilla indicates that volcanic islands in the region served as sources of pottery (or volcanic temper) for these two islands. 相似文献