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981.
Despite wide ranging interpretations of the concept of sustainable development there is growing consensus about the ecological, social, and economic conditions necessary to foster a sustainability transition. In addition to quantitative assessments of sustainability indicators, qualitative process indicators are being identified. For example, active, democratic, and inclusive decision-making are shown to lead to more informed decisions and, presumably, more sustainable use systems. The creation of these conditions, however, often requires bridging lack of mutual trust and scientific uncertainty. And while the ideals of sustainable development suggest that all stakeholders get what they want, without compromise nothing approaching sustainable development is attainable. Obstructing compromise, environmental ideology represents a key remaining hurdle to achieving a middle ground in environment and development debates. In the 1990s, the US-based Trillium Corporation sought to implement a large-scale logging project in Tierra del Fuego, Chile, but was rebuffed by environmentalists who embraced ecotourism as the preferred development option. The case is analyzed in the context of calls to reconsider conceptually nature-society relationships and ideas in sustainability science about which land management systems best match sustainability goals. Findings show that the decision-making process for determining whether or not to implement the logging project was flawed. We explore two implications. First, achieving sustainable development requires a consensus view of nature-society relationships that embraces humanized landscapes. Second, inclusive and effective decision-making about sustainable development necessitates free and open exchange of information, collective learning about regional environment and development, and the identification of compromise positions. 相似文献
982.
Wenfeng Wang Yong Qin Chongtao Wei Zhuangfu Li Yinghai Guo Yanming Zhu 《International Journal of Coal Geology》2006,68(3-4):223-232
Analyses of the macerals, ash, sulfur and 43 major and trace elements were performed on samples of feed coal, cleaned coal, middlings and slime collected from the Antaibao coal preparation plant, China, and also on samples from coal preparation experiments. This study is focused on the partitioning of elements and macerals during coal preparation and potential environment aspects of the elements.The conclusions are as follows: (1) in comparison with the feed coal, the cleaned coal has a higher vitrinite content and relatively lower inertinite and exinite contents, whereas the middlings and slime have lower vitrinite and exinite contents, and relatively higher inertinite contents. The vitrinite contents in the size-segregated cleaned coals were observed to show a slightly increasing tendency with increasing particle size, while the inertinite contents decreased. (2) Physical coal cleaning is not only effective for removal of ash and sulfur, but also in reducing the concentration of most elements. As, Cd, Co, Cs, Hg, Fe, K, Mg, Nb and Ni are observed to show a high degree of removal, while Br, Be, Cu, U, Mn, Zn and organic sulfur are enriched in the cleaned coal and show a lower degree of removal. The large-sized cleaned coal is cleaner than the smaller sized fractions. (3) The middlings, especially the slime, are enriched in S, Hg, Cr, V, Zn, etc., so that these fractions should not be directly used as fuel. In addition, the concentration of Pb and V in the process water exceeds the limit of relevant environmental water quality standard. Consequently, it is necessary to develop new processes to remove ash, sulfur and hazardous trace elements to the maximum extent. Further studies on deep processing of the middlings and slime and cleaning of the process water should also be performed. 相似文献
983.
In this paper, we investigate the context within which struggles for environmental justice are taking place in India. We explore the ways in which postcolonial patterns of government and governance in India affect the ends, the means and the representation of these struggles, focusing on three particular areas: state reform, the judiciary and public interest litigation, and environmental social movements. We argue that India differs from west in the ambitious yet incomplete and contradictory nature of government-sponsored intervention in the environment, and in the particular nature of its public sphere, both of which have been important in shaping struggles for environmental justice. Our wider intention is not merely to catalogue these differences, but to use the Indian material to raise questions about the emphases and implicit assumptions of western environmental justice literature, and reflect on how these may be need reconsideration when working in postcolonial contexts. 相似文献
984.
Enacting environmental justice in Singapore: Performative justice and the Green Volunteer Network 总被引:1,自引:0,他引:1
Kersty Hobson 《Geoforum》2006,37(5):671-681
Environmental justice research has of late expanded beyond its’ original focus on the distribution of environmental ‘bads’ to debate injustices at a wide array of sites and scales. Despite this expansion, the applicability of an environmental justice framework to seemingly apolitical and banal expressions of environmental concerns remains open to question. This paper argues that environmental justice struggles can be located in the mundane environmental politics of Singapore, by employing a performative rather than rights-based approach to both justice and politics. It draws on qualitative research into volunteers’ practices in one Singaporean environmental organisation, and asserts that through their focus on experiential learning and re-inscribing ‘developmental’ spaces as spaces of care and justice, volunteers seek to redress the social, political and environmental injustices replete within the spatial politics of Singapore. 相似文献
985.
986.
It is possible to reconstruct the past variation of an environmental variable from measured historical indicators when the
modern values of the variable and the indicators are known. In a Bayesian statistical approach, the selection of a prior probability
distribution for the past values of the environmental variable can then be crucial and the selection therefore should be made
carefully. This is particularly the case when the data are noisy and the statistical model used is complex since the influence
of the prior on the results can then be especially strong. It can be difficult to elicit the prior probability distribution
from the available information, since usually there are no measured data on the past values of the variable one wants to reconstruct
and different reconstructions are typically consistent with each other only at a coarse level. To overcome these difficulties
we propose to use a non-informative smoothing prior, possibly in combination with an informative prior, that simply penalizes
for roughness of the reconstruction as measured by the variability of its values. We believe that it can sometimes be easier
to set an overall prior distribution on the roughness than to agree on a prior for the actual values of the reconstructed
variable. Note that by using a smoothing prior one incorporates into the model itself the smoothing step usually done before
or after the actual numerical reconstruction. Another idea proposed in this paper is to integrate the reconstruction model
with a multiscale feature analysis technique known as SiZer. Multiscale analysis of the posterior distribution of the reconstructed
variable makes it possible to infer its statistically significant features such as trends, maxima and minima at several different
time scales. While only temperature is considered in this paper, the technique can be applied to other environmental variables. 相似文献
987.
Jens Christian Refsgaard Jeroen P. van der Sluijs James Brown Peter van der Keur 《Advances in water resources》2006
Although uncertainty about structures of environmental models (conceptual uncertainty) is often acknowledged to be the main source of uncertainty in model predictions, it is rarely considered in environmental modelling. Rather, formal uncertainty analyses have traditionally focused on model parameters and input data as the principal source of uncertainty in model predictions. The traditional approach to model uncertainty analysis, which considers only a single conceptual model, may fail to adequately sample the relevant space of plausible conceptual models. As such, it is prone to modelling bias and underestimation of predictive uncertainty. 相似文献
988.
Windsor–Essex County is a major cross-border truck and transportation route, with significant localized industrialization as well as rural and farming areas. Magnetic property measurements (in-field and laboratory susceptibility, frequency-dependent susceptibility, hysteresis properties, thermomagnetic and thermosusceptibility curves, anhysteretic and isothermal magnetizations) were made in order to determine the potential for using such variables to distinguish between natural and anthropogenic pollutants. In-field magnetic susceptibility measured on 324 soil sampling sites on a 0.5–2 km grid spacing through Windsor–Essex County ranged from 3.7 × 10− 6 to 305.2 × 10− 6 SI (average 36.2 ± 35.8 × 10− 6 SI), and showed that high magnetic susceptibility values were obtained on soil sampling sites in and around the cities/towns of Windsor, Harrow, Olinda and Oakland and near the beaches of Point Pelee National Park (PPNP) and Deerbrook, whereas lower susceptibility values were observed in near the towns of Lakeshore and Essex. On this grid spacing, Highway 401 (the major truck route) did not show anomalous susceptibility values; however, closer (1–3 m) sampling on other roads did show anomalously high values, suggesting that the coarser grid spacing may have missed anomalies. Laboratory measurements indicated that the dominant magnetic mineral in the Windsor–Essex County soils is magnetite; however, the grain size is variable. Pseudo-single domain (PSD)–multidomain (MD) magnetite is generally found on beaches and in PPNP, whereas single domain (SD)–PSD magnetite has been found near the City of Windsor and other towns. While certain correlations exist between some anthropogenic activities and the measured magnetic susceptibility and magnetic property values, no overall correlation can be made. A variety of geologic and anthropogenic factors must be considered when interpreting the origin of the magnetic signal in a particular area. 相似文献
989.
John Shroder 《GeoJournal》2007,70(2-3):91-107
Afghanistan has long been backward and underdeveloped where centuries of desertification, deforestation, overgrazing and environmental
degradation have combined with successive invasions, violence, and terrorism to reduce the population to abject poverty. In
the post 9/11 world, development of Afghanistan is seen as the only hope to revive the failed nation and reduce its threat
to the external world. New assessments of natural resources offer many solutions to old problems of development and the potential
economic functionality through renewal of the collapsed state. Oil, gas, copper, iron, gemstones, and a number of other resources,
combined with a renewed transportation grid, offer a viable solution that is now underway to possibly produce a somewhat more
promising future, providing that corruption, renewed violence, and environmental despoliation can be kept to a minimum. 相似文献
990.
Dunsheng Xia Xi Chun Jan Bloemendal Richard C. Chiverrell Fahu Chen 《Environmental Geology》2007,51(8):1425-1437
Rock magnetic measurements have been applied to two adjacent loessial soil sections from a small region, SE Iceland. The soils
are composed of reworked locally derived sediment (including airfall tephra) and also contain several visible discrete airfall
tephra layers. The main magnetic minerals in the airfall tephras are ferrimagnetic (e.g. magnetite) with paramagnetic minerals
also present. The main magnetic grain sizes in the tephras are pseudo single domain. The results show that individual tephras
do not have unique magnetic signatures that can be used for identification and correlation between sedimentary sequences.
However, a correlation of tephra layers was achieved through the application of statistical techniques to a comprehensive
dataset of magnetic parameters. Similarity coefficients and Euclidian distance measures were used to identify the best correlation
between tephra layers in the two soil profiles. The technique works well providing some tephras present within both profiles
have been formally identified (e.g. Oraefajokulla
ad 1362) using electron microprobe analyses. Given this initial framework, the statistical analyses of the magnetic parameters
can help in the identification and correlation of unknown tephras between two soil profiles. 相似文献