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791.
We introduce a new method for visualizing and analyzing information landscapes of ideas and events posted on public web pages through customized web-search engines and keywords. This research integrates GIScience and web-search engines to track and analyze public web pages and their web contents with associated spatial relationships. Web pages searched by clusters of keywords were mapped with real-world coordinates (by geolocating their Internet Protocol addresses). The resulting maps represent web information landscapes consisting of hundreds of populated web pages searched by selected keywords. By creating a Spatial Web Automatic Reasoning and Mapping System prototype, researchers can visualize the spread of web pages associated with specific keywords, concepts, ideas, or news over time and space. These maps may reveal important spatial relationships and spatial context associated with selected keywords. This approach may provide a new research direction for geographers to study the diffusion of human thought and ideas. A better understanding of the spatial and temporal dynamics of the ‘collective thinking of human beings’ over the Internet may help us understand various innovation diffusion processes, human behaviors, and social movements around the world.  相似文献   
792.
793.
Since the end of the commercial fur seal hunt in 1984, the economy of the Pribilof Islands, Alaska, has lacked a stable, lasting basis. As a contribution to the effort to understand and promote the effective management of the Pribilof Islands as a social–ecological system, we examined current and recent conditions on the islands to assess local perceptions of, and prospects for, economic, social and environmental well-being. We found few correlations between environmental conditions and socio-economic indicators. The lack of apparent connection between population levels and economic or environmental stimuli is likely attributable to one or more of several factors: (a) modest economic dependence on the environment; (b) predominance of other economic inputs to the economies of the islands; (c) islanders basing residence choices largely on non-economic factors; and (d) the islanders' tolerance for economic fluctuations and uncertainty. These results suggest economic analysis alone is insufficient to explain the dynamics of this social–ecological system, contrary to many other case studies and an expectation of tight coupling and clear connections between society and ecology in the Pribilofs.  相似文献   
794.
Effective risk communication is central to good environmental risk management. While studies have shown that newspapers are the primary source of information to the public regarding environmental issues, little is known about how environmental news is used as a risk‐communication tool. This article explores the role of local information systems in risk communication, using newspaper content analysis as well as in‐depth interviews with journalists and community residents to develop a case study of an environmental assessment process for a nonhazardous industrial‐waste landfill. Results indicate that risk messages were chosen and shaped by journalists on the basis of their own exigencies. In addition, while newspapers were a major source of risk information, their impact was mitigated by resident distrust and access to other information sources, most notably their own personal information networks. These results have implications for environmental policy, as decision makers often use—either passively or actively—print media as a risk‐communication tool.  相似文献   
795.
Social capital has the potential to influence the success of biodiverse carbon plantings in the face of uncertainty amongst rural landholders about the need or efficacy of efforts to address climate change through tree planting. We conducted 17 face-to-face semi-structured interviews with landholders in Victoria, Australia who voluntarily participate in biodiverse carbon plantings on their land, focusing in particular on the role of social capital for understanding how ‘early adopters' can advocate for programs locally. The interviews revealed the importance of social networks and the profound impact of trusted peers on the diffusion of carbon planting schemes. These social capital dimensions are especially important for shaping ongoing participation and the ways in which participants become active agents in trusted relationships that influence the participation of others. Our results suggest that the positive impact of social networks can counteract doubts about the validity of climate adaptation responses such as carbon planting, and enable landholders to connect the program with their existing stewardship motivations. The ability for early adopters of the program to demonstrate the physical materialisation of their plantings to others was vital to this process. We propose that targeting champions and trusted peers in local communities could accelerate the proliferation of biodiverse carbon planting schemes.  相似文献   
796.
Previous studies have shown that moisture availability in the central highlands of Mexico during the last 3000 years has been highly variable, but evidence remains ambiguous since the climatic signal is partially masked by that of human activity. Here we use two isotope systems to provide evidence for environmental change in Laguna Zacapu, Michoacán covering this time period. Carbon isotope ratios of organic material suggest that there have been fluctuations in the carbon pool related to plant productivity, possibly as a result of changes in the abundance of aquatic plants around the lake margins. The drainage basin and lake have been managed intensively during the 20th century. Lake level apparently fell during the early part of the century, but has been artificially controlled since the 1950s. The oxygen isotope ratios from diatom silica should provide the more unambiguous climate signal, although we show that the interpretation of the diatom oxygen isotope record is far from straight forward. Zacapu is a spring-fed, non-evaporating system and changes in δ18Odiatom are likely to be a function of changes in δ18O of precipitation, due to either temperature and salinity variation in the Gulf of Mexico (associated with changes in the Bond cycles from the North Atlantic or the Loop current from the Carribean) and/or changing moisture contributions from different air masses (Gulf of Mexico vs. Pacific). Changes in the Gulf of Mexico are possibly at a resolution comparable to the periodicity we see in the δ18Odiatom record, although without better dating the comparison is speculative.  相似文献   
797.
While climate change action plans are becoming more common, it is still unclear whether communities have the capacity, tools, and targets in place to trigger the transformative levels of change required to build fundamentally low-carbon, resilient, healthy communities. Evidence increasingly supports the finding that this transformation is not triggered by climate policy alone, but rather is shaped by a broad array of decisions and practices that are rooted in underlying patterns of development. Even so, these findings have rarely penetrated the domain of practice, which often remains squarely focused on a relatively narrow set of climate-specific policies. This article builds a conceptual framework for understanding the dynamics of community-level development path transformations that may both dramatically reduce GHG emissions and significantly enhance community resilience. This framework illuminates eight critical enablers of innovation on climate change, each of which is illustrated by compelling examples of community-level experimentation on climate change across the province of British Columbia, Canada. It is concluded that community-based climate (or sustainability) policy might be more likely to trigger development path shifts if it employs a longer time horizon, recognition of adaptability and feedbacks, integrated decision making, and systems thinking.  相似文献   
798.
Nearly all of our understanding of rocky inter‐tidal ecology comes from studies conducted at low tide. To study inter‐tidal organisms at high tide, we anchored waterproof digital GoPro® video cameras in wave‐exposed tidepools and recorded the daytime movements of the black turban snail, Tegula funebralis, over the tidal cycle between May and August 2012 near Bodega Bay, California. Overall, snails moved more quickly and presumably foraged more during low tides and on days with warmer air and perhaps water temperatures. This is similar to other ectotherms that exhibit increased metabolic rates, movement and foraging in warmer conditions. Snails also moved less during flood and high tides, may have moved downward in tidepools at flood tides, and showed evidence of reduced activity on days with larger waves. This inactivity and refuge seeking may have been a strategy to avoid dislodgment by waves. Analysis of snail trajectories showed foraging bouts indicated by alternating zig‐zagging and straight movement. There was no effect of temperature, wave height, or tidal phase on distribution of snail turning angles, suggesting that they may have foraged consistently but moved faster during warm conditions and low tides, thereby grazing a larger area. This is one of few direct recordings of inter‐tidal organisms on wave‐exposed rocky shores during high tide. The methods used here are easily transferable to other studies, which are needed to increase our understanding of behaviors that structure rocky shore communities during high tide.  相似文献   
799.
The seasonal mean extra-tropical atmospheric response to El Niño/Southern Oscillation (ENSO) is assessed in the historical and pre-industrial control CMIP5 simulations. This analysis considers two types of El Niño events, characterized by positive sea surface temperature (SST) anomalies in either the central equatorial Pacific (CP) or eastern equatorial Pacific (EP), as well as EP and CP La Niña events, characterized by negative SST anomalies in the same two regions. Seasonal mean geopotential height anomalies in key regions typify the magnitude and structure of the disruption of the Walker circulation cell in the tropical Pacific, upper tropospheric ENSO teleconnections and the polar stratospheric response. In the CMIP5 ensembles, the magnitude of the Walker cell disruption is correlated with the strength of the mid-latitude responses in the upper troposphere i.e., the North Pacific and South Pacific lows strengthen during El Niño events. The simulated responses to El Niño and La Niña have opposite sign. The seasonal mean extra-tropical, upper tropospheric responses to EP and CP events are indistinguishable. The ENSO responses in the MERRA reanalysis lie within the model scatter of the historical simulations. Similar responses are simulated in the pre-industrial and historical CMIP5 simulations. Overall, there is a weak correlation between the strength of the tropical response to ENSO and the strength of the polar stratospheric response. ENSO-related polar stratospheric variability is best simulated in the “high-top” subset of models with a well-resolved stratosphere.  相似文献   
800.
The Niwot Ridge and Green Lakes Valley (NWT) long-term ecological research (LTER) site collects environmental observations spanning both alpine and subalpine regimes. The first observations began in 1952 and have since expanded to nearly 300 available datasets over an area of 99 km2 within the north-central Colorado Rocky Mountains that include hydrological (n = 101), biological (n = 79), biogeochemical (n = 62), and geographical (n = 56) observations. The NWT LTER database is well suited to support hydrologic investigations that require long-term and interdisciplinary data sets. Experimentation and data collection at the NWT LTER are designed to characterize ecological responses of high-mountain environments to changes in climate, nutrients, and water availability. In addition to the continuation of the many legacy NWT datasets, expansion of the breadth and utility of the NWT LTER database is driven by new initiatives including (a) a catchment-scale sensor network of soil moisture, temperature, humidity, and snow-depth observations to understand hydrologic connectivity and (b) snow-albedo alteration experiments using black sand to evaluate the effects of snow-disappearance on ecosystems. Together, these observational and experimental datasets provide a substantial foundation for hydrologic studies seeking to understand and predict changes to catchment and local-scale process interactions.  相似文献   
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