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101.
102.
1 Introduction As a special kind of tourism, glacier tourism is popular to tourists all over the world owing to its meeting tourists’ needs for seeking after freshness, difference, surprise and risk. Differing from conventional tourism, glacier tour- ism has its special characters while there is little literature on it. It is of great significance to study its characters and seek after the harmonious development in exploitation and protection of glacier tourism resources. Glacier tourism refe…  相似文献   
103.
This overview discusses old and new results as to the controversy on the past glacier extension in High Asia, which has been debated for 35 years now. This paper makes an attempt to come closer to a solution. H.v. Wissmann's interpretation (1959) of a small-scale glaciation contrasts with M. Kuhle's reconstruction (1974) of a large-scale glaciation with a 2.4 million km2 extended Qinghai-Xizang (Tibetan) inland glaciation and a Himalaya-Karakorum icestream network. Both opinions find support but also contradiction in the International and Chinese literature (Academia Sinica). The solution of this question is of supraregional importance because of the subtropical position of the concerned areas. In case of large albedo-intensive ice surfaces, a global cooling would be the energetical consequence and, furthermore, a breakdown of the summer monsoon. The current and interglacial heat-low above the very effective heating panel of the Qinghai-Xizang (Tibetan) Plateau exceeding 4000 m, which gives rise to this monsoon circulation, would be replaced by the cold-high of an inland ice. In addition, the plate-tectonically created Pleistocene history of the uplift of High Asia — should the occasion arise up to beyond the snowline (ELA) —would attain a paleoclimatically great, perhaps global importance. In case of a heavy superimposed ice load, the question would come up as to the glacio-isostatic interruption of this primary uplift. The production of the loesses sedimentated in NE-China and their very probable glacial genesis as well as an eustatic lowering of the sea-level by 5 to 7 m in the maximum case of glaciation are immediately tied up with the question of glaciation we want to discuss. Not the least, the problems of biotopes of the sanctuary-centres of flora and fauna, i.e., interglacial re-settlement, are also dependent on it. On the basis of this Quaternary- geomorphological-glaciological connection, future contributions are requested on the past glaciation, the current and glacial permafrost table and periglacial development, the history of uplift, and the development of Ice Age lakes and loess, but also on the development of vegetation and fauna in High Asia.  相似文献   
104.
G. Richards  R. D. Moore 《水文研究》2003,17(9):1733-1753
This study examined suspended sediment concentration (SSC) during the ablation seasons of 2000 and 2001 in Place Creek, Canada, a steep, glacier‐fed mountain stream. Comparison of stream flow in Place Creek with that in an adjacent, almost unglacierized catchment provided a rational basis for separating the ablation seasons into nival, nival–glacial, glacial and autumn recession subseasons. Distinct groupings of points in plots of electrical conductivity against discharge supported the validity of the subseasonal divisions in terms of varying hydrological conditions. Relationships between SSC and discharge (Q) varied between the two study seasons, and between subseasons. Hysteresis in the SSC–Q relationship was evident at both event and weekly time‐scales. Some suspended sediment released from pro‐glacial Place Lake (the source of Place Creek) appeared to be lost to channel storage at low flows, especially early in the ablation season, with re‐entrainment at higher flows. Multiple regression models were derived for the subseasons using predictor variables including Q, Q2, the change in Q over the previous 3 h, cumulative discharge over the ablation season, total precipitation over the previous 24 h and SSC measured at 1500 hours as an index value for each day. The models produced adjusted R2 values ranging from 0·71 to 0·91, and provided tentative insights into the differences in SSC dynamics amongst subseasons. Introduction of the index value of SSC significantly improved the model fit during the nival–glacial and glacial subseasons for both years, as it adjusts the model to the current condition of sediment supply. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
105.
Three trend surface techniques are used to evaluate the nature and distribution of the surface sediments of a rock glacier. Trend surface analysis, vector trend analysis, and most predictable surface (MPS)mapping suggest that long-term rock glacier creep causes the highly variable debris cover to display crude sorting and orientation patterns. Poorly sorted and randomly oriented surface materials may be the result of insufficient time for slowly evolving rock glacier sediment distributions to be established and/or the site of glacial erosion or deposition.  相似文献   
106.
107.
Spatially-explicit estimation of aboveground biomass(AGB) plays an important role to generate action policies focused in climate change mitigation,since carbon(C) retained in the biomass is vital for regulating Earth’s temperature.This work estimates AGB using both chlorophyll(red,near infrared) and moisture(middle infrared) based normalized vegetation indices constructed with MCD43A4 MODerate-resolution Imaging Spectroradiometer(MODIS) and MOD44B vegetation continuous fields(VCF) data.The study area is located in San Luis Potosí,Mexico,a region that comprises a part of the upper limit of the intertropical zone.AGB estimations were made using both individual tree data from the National Forest Inventory of Mexico and allometric equations reported in scientific literature.Linear and nonlinear(expo-nential) models were fitted to find their predictive potential when using satellite spectral data as explanatory variables.Highly-significant correlations(p = 0.01) were found between all the explaining variables tested.NDVI62,linked to chlorophyll content and moisture stress,showed the highest correlation.The best model(nonlinear) showed an index of fit(Pseudo-r2) equal to 0.77 and a root mean square error equal to 26.00 Mg/ha using NDVI62 and VCF as explanatory variables.Validation correlation coefficients were similar for both models:lin-ear(r = 0.87**) and nonlinear(r = 0.86**).  相似文献   
108.
Mountain glaciers have an obvious location advantage and tourist market condition over polar and high latitude glaciers. Due to the enormous economic benefit and heritage value, some mountain glaciers will always receive higher attention from commercial media, government departments and mountain tourists in China and abroad. At present, more than 100 glaciers have been developed successfully as famous tourist destinations all over the world. However, global climate change seriously affects mountain glaciers and its surrounding environment. According to the current accelerated retreat trend, natural and cultural landscapes of some glaciers will be weakened, even disappear in the future. Climate change will also inevitably affect mountain ecosystems, and tourism routes under ice and glacier experience activities in these ecosystems. Simultaneously, the disappearance of mountain glaciers will also lead to a clear reduction of tourism and local economic benefits. Based on these reasons, this paper took Mt. Yulong Snow scenic area as an example and analyzed the retreat trend of a typical glacier. We then put forward some scientific and rational response mechanisms and adaptation models based on climate change in order to help future sustainable development of mountain glacier tourism.  相似文献   
109.
In order to thoroughly investigate the diversity of glacier microorganisms, four DNA extraction methods with different lysis patterns were tested and two screened methods (the Bosshard-Bano method and the Zhou method) were optimized for the most effective form of the filter membrane (cut vs. uncut), the DNA extraction method, and the precipitation method. The two optimized methods were then compared with the commercial Mo-Bio DNA extraction kit, and the results showed that the kit was generally suitable for extraction of microorganism DNA from glacier surface snow. Procedurally, it was found that a modified Bosshard- Bano method (i.e., cutting the filter membrane into pieces, using a specific lysis pattern [lysozyme (5 mg/mL)-protease K (1 mg/mL)-CTAB (1%)-SDS (1%)], performing the extraction only once by chloroform-isoamyl alcohol (24:1), and conducting DNA precipitation by pure ethanol) was also an effective and less expensive method for extraction of microorganism DNA from glacier surface snow.  相似文献   
110.
This paper recognizes the contribution of Professor Wilfried Haeberli for his inspiration and leadership in the field of permafrost science and his generous encouragement, both direct and indirect, to the ETH Researchers who have, through him, endeavoured to contribute to this fascinating research area. The multidisciplinary investigations described in this paper have focused on three rock glaciers, Muragl, Murtèl‐Corvatsch and Furggwanghorn, all of which have been subject to a varying degree of prior study, and which are continuing to attract new generations of researchers to understand and explain the processes and predict future behaviour. This paper marks a stage at which it is possible to summarize some advances in the state of the art and associated innovations that can be attributed to early motivation by Wilfried Haeberli and offers a tribute as well as gratitude for his ongoing feedback and advice. Some thoughts on the development of thermokarst due to water ponding and flow, and a conceptual model of geotechnical mechanisms that aim to explain some aspects of rock glacier kinematics, are also introduced.  相似文献   
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