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11.
Following the 2010–2011 earthquakes in Christchurch, New Zealand, many nonprofit organizations changed or expanded services to address emergent or compounded risks. This research is based on interviews with thirty local community nonprofit managers and discussions with five staff focus groups conducted in 2014. Preexisting nonprofits with flexible organizational structures and emergent nonprofits succeeded in providing services during the emergency response and early recovery phases; nonprofits contracted with the government were better suited for long-term recovery. Shared resources among nonprofit agency connections contributed to successful transitions from response to recovery. Similar organizational resilience factors might occur in other major cities following disasters. 相似文献
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A new mechanism is suggested for the generation of the interference fold pattern which characterizes the Limpopo Mobile Belt. The mechanism is directly related to shear movement along the Tuli-Sabi Shear Zone, renamed the Tuli-Sabi Straightening Zone. The mobile belt is regarded as a taphrogenic lineament (McConnell, 1974) and its generation is compatible with the tectonic environment active in Proterozoic times according to Sutton and Watson (1974). Field evidence shows that the Tuli-Sabi Straightening Zone dies out in Botswana at Moshakabela, and it is reasoned that the mobile belt as a whole also disappears in this vicinity. It does not extend into central and western Botswana beneath the Karroo and Kalahari cover. Detailed examination of ERTS-1 imagery of northeastern Botswana strengthens these deductions. The Tuli-Sabi Straightening Zone and the characteristic fold patterns of the mobile belt can be seen quite clearly on the satellite imagery. Furthermore, the Tuli-Sabi Straightening Zone appears to be displaced southwards at the international boundary between Botswana and Rhodesia. The existence of a fold belt trending about N150° superimposed on the Limpopo Mobile Belt in the west of the area is postulated which is not the Shashe Mobile Belt (Crockett, 1967). 相似文献
14.
E. Mazor B. Th. Verhagen J. P. F. Sellschop M. T. Jones L. G. Hutton 《Environmental Geology》1981,3(4):195-199
In the reconstruction of the chemical evolution of mineral waters, sodium exchange for calcium and magnesium, upon contact
with soil and rocks, is often suggested. Such a process has been observed to take place on a large (and rapid) scale in NaCl
waste disposal: that infiltrated to the local groundwater at Lobatse, Botswana. The process was repeated in laboratory experiments.
Visiting Scientist at the Nuclear Physics Research Unit, University of the Witwatersrand, Johannesburg, South Africa, during
1972. 相似文献
15.
R. Lamoreaux V.I. Keilis-Borok L.K. Hutton 《Physics of the Earth and Planetary Interiors》1983,31(3):193-201
A scaling law for the occurrence of aftershocks in southern California is proposed which suggests that the number of aftershocks is independent of the magnitude of the mainshock if aftershocks are counted in the magnitude interval from (Mm ? Δ) to Mm. 相似文献
16.
The NMR spectra of 27Al and 23Na and the EPR spectra of Fe3+ and Mn2+ have been studied in a range of plagioclase feldspars, of intermediate composition. Many of these crystals have previously been investigated by TEM methods (McLaren and Marshall, 1974). The broad, central 27Al signals observed in labradorites have been interpreted in terms of an overall order/disorder of the Al/Si distribution. Spin Hamiltonian parameters have been determined for the Fe3+ spectra observed in labradorites and bytownites; these spectra were similar and yielded evidence of disordering of the Al/Si distribution. The severe limitations imposed by the variety of sites, the complex microstructures and the disordering, limit the structural information available from the resonance methods. 相似文献
17.
Freshwater flow to the San Francisco Bay‐Delta estuary over nine decades (Part 1): Trend evaluation 下载免费PDF全文
The San Francisco Bay‐Delta estuary and its upstream watershed have been highly modified since exploration and settlement by Europeans in the mid‐18th century. Although these hydrologic alterations supported the growth of California's economy to the eighth largest in the world, they have been accompanied by significant declines in native aquatic species and subsequent efforts to reverse these declines through flow management. To inform ongoing deliberations on management of freshwater flows to the estuary, we examined a recent nine‐decade hydrologic record to evaluate seasonal and annual trends in reported Delta outflow. Statistically significant trends were observed in seasonal outflows, with decreasing trends observed in 4 months (February, April, May, and November) and increasing trends observed in 2 months (July and August). Trend significance in early‐to‐mid autumn (September and October) is ambiguous due to uncertainty associated with in‐Delta agricultural water use. In spite of increasing water use over the period examined, we found no statistically significant annual trend in Delta outflow, a result likely due to large inter‐annual variability. Linkages between outflow trends and changes in upstream flows and coincident developments such as reservoir construction and operation, out‐of‐basin imports and exports, and expansion of irrigated agriculture are discussed. To eliminate inter‐annual variability as a factor, change attribution is explored using modelled flows and fixed climatology in a companion paper. 相似文献
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19.
Climate change impacts are already happening through the world, and it is now clear that there is the need for an adaptive response from global institutions down to the local level. Reducing vulnerability to cope with climate variability might be more challenging in tropical countries than in North America or Europe. The ten papers of this special issue were presented during the Adaptclim conference that was held by the Sinergia Project, the CLARIS LPB project, and the GeoData Institute in Asunción, Paraguay, in 2010. All papers, except one regarding the Brahmaputra Basin in South Asia, present studies from South America. These studies are first contextualized geographically and then are related one to another by a simplified vulnerability concept linking climate stress to sensitivity and adaptive capacity of natural and human systems. One half of the papers focus on actual or future climate change and the present-day causes of the vulnerability of natural and agrosystems. Droughts are and will be the main source of stress for agriculture in South America. Increasing fragmentation of forest of the center of this continent is aggravating their vulnerability to dry spells. Another half of the studies of this special issue deal with the adaptive capacity human populations to system perturbations produced or enhanced by climate change. The studies point out inclusion of traditional knowledge and involvement of local actors in their own vulnerability assessment to increase adaptive capacity. These elements of climate justice, giving voice to those less responsible for carbon emissions but bearing their most severe consequences, allow the particular needs of a community to be considered and can direct adaptation policy toward preserving or rebuilding their specific capabilities under threat from climate change. The special issue also made clear that a basin analysis of the climate change problem could provide information, results, and methods more readily of use for the local population and decision makers. 相似文献
20.
Gary R. Watmough Peter M. Atkinson Craig W. Hutton 《International Journal of Applied Earth Observation and Geoinformation》2011
The automated cloud cover assessment (ACCA) algorithm has provided automated estimates of cloud cover for the Landsat ETM+ mission since 2001. However, due to the lack of a band around 1.375 μm, cloud edges and transparent clouds such as cirrus cannot be detected. Use of Landsat ETM+ imagery for terrestrial land analysis is further hampered by the relatively long revisit period due to a nadir only viewing sensor. In this study, the ACCA threshold parameters were altered to minimise omission errors in the cloud masks. Object-based analysis was used to reduce the commission errors from the extended cloud filters. The method resulted in the removal of optically thin cirrus cloud and cloud edges which are often missed by other methods in sub-tropical areas. Although not fully automated, the principles of the method developed here provide an opportunity for using otherwise sub-optimal or completely unusable Landsat ETM+ imagery for operational applications. Where specific images are required for particular research goals the method can be used to remove cloud and transparent cloud helping to reduce bias in subsequent land cover classifications. 相似文献