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51.
The suitability of linden and elder as biomonitors was evaluated in the tourist zone of the Bor region well known for pyrometallurgical copper production. The concentrations of As, Cu, Pb and Zn in the soil, washed and unwashed leaves and roots of linden and elder were determined. The absorption of As, Cu, Pb and Zn from soil to roots and leaves, as well as the translocation of the studied elements from roots to leaves, was analysed. It was observed that the soil in the tourist zone of Bor (Bor lake and Brestovac spa) was greatly polluted with Cu and As. Linden and elder leaves can be used as a low-cost material for detection of As, Cu, Pb and Zn in the atmospheric deposition, which was concluded due to the amounts of these elements removed after a washing treatment. Thus, canopies of linden and elder might have an important role in the removal of the polluting substances from the air. The elder leaves were more suitable to be used for indication of environmental pollution with As, Cu and Pb than the linden leaves. The area of the Bor lake sampling site had higher air pollution with As and Pb than Brestovac spa, since greater amounts of As and Pb were washed off the linden and elder leaves from the Bor lake sampling site. The linden and elder used different adaptation strategies in conditions of the increased soil and air pollution. These strategies were based on different efficiencies of element absorption from the soil and on limited or efficient translocation of the studied elements from roots to leaves, and therefore, they have an important role in the biogeochemical cycling of the examined elements in the environment.  相似文献   
52.
The severe bora case that lasted from 13 to 15 November 2004 has been selected for the analysis of the bora of Pag’s ribs, which occurs in the northern part of the eastern Adriatic coast over the Pag island area (Croatia). According to the measurements from automatic stations, the MM5 numerical model is successful in the 10-min mean wind speed prediction at 10-m height. The vertical analysis of the wind speed and potential temperature also gave satisfactory results. At the commencement of the bora the modelled wind had a magnitude of 20ms−1 at 10-m height in the Pag island area, which sharply attenuated in the cross direction and to the open sea. In this way the model has proved successful in predicting the characteristics of the bora of Pag’s ribs. Potential vorticity (PV) at 600m has lower values within PV banners than during the developed bora. The consequence is a strong jet emanating from the nearest gap. The vertical cross-sections through the centre of the gap point out a permanent hydraulic-like flow. At the time of the bora of Pag’s ribs the highest modelled turbulent kinetic energy is found in the jump-like region above the inversion and within the boundary layer along the lower boundary, ranging from 6–8m2 s−2. It is concluded that the dissipation in the hydraulic jumps and the wave breaking regions are the reasons for PV generation.  相似文献   
53.
Copepod distribution as an indicator of epikarst system connectivity   总被引:2,自引:0,他引:2  
The distribution of 27 copepod species was determined in 35 drips in four Slovenian caves (Dimnice, Postojna Planina Cave System, Škocjanske Jame, Županova Jama), and of ten species from 13 drips in one US cave (Organ Cave, West Virginia). The dripping water comes from epikarst, the skin of karst. A significant fraction of the copepod species found (nine species in Slovenia and three in West Virginia) occurred over a maximum linear extent of 100 m. These and other localized distributions probably resulted from colonization of epikarst by an ancestral surface population in a single location, with subsequent lateral spread in the direction of epikarst flow. This suggests that the distribution of copepods could potentially be used to trace major flow paths in epikarst without the need for the injection of dyes or other tracers.
Résumé La distribution de 27 espèces de copépodes a été déterminée dans 35 zones de percolation de quatre grottes slovènes (Dimnice, système de grottes Postojna Planina, Škocjanske Jame, Županova Jama) et grace à dix espèces de 13 zones de percolation d’une grotte des Etats-Unis (Grotte Organ, Ouest de la Virginie). L’eau de percolation provient de l’épikarst, la partie supérieure du karst. Une fraction importante des espèces de copépodes trouvées (9 espèces en Slovénie et 3 dans l’Ouest de la Virginie) s’étendait sur une longueur maximum de 100 m. Ces dernières ainsi que d’autres distributions localisées étaient probablement issues de la colonisation par une population ancienne de surface, de zones localisées de l’épikarst, puis par une dispersion latérale dans la direction de l’écoulement dans l’épikarst. Ceci suggère que la distribution des copépodes pourrait potentiellement être utilisée pour identifier les principales trajectoires d’écoulement dans l’épikarst, sans utiliser l’injection de colorants ou d’autres traceurs.

Resumen Se determina la distribución de 27 especies de copépodo en 35 gotas de cuatro cavernas de Eslovenia (Dimnice, Sistema de Caverna Planina Postojna, Jame Škocjanske, y Jama Županova), y de diez especies en 13 gotas de una caverna de Estados Unidos (Caverna órgano, Virginia Occidental). El agua que gotea se deriva del epikarst, la piel del karst. Una fracción significativa de las especies de copépodos encontradas (9 especies en Eslovenia y 3 en Virginia Occidental) se presentaron en una extensión linear máxima de 100 m. Estas y otras distribuciones localizadas resultaron probablemente de colonización del epikarst por poblaciones superficiales ancestrales en una sola localización, con una expansión lateral subsiguiente en la dirección de flujo epikárstico. Esto sugiere que la distribución de copépodos podría tener un uso potencial para trazar rutas de flujo principales en epikarst sin tener la necesidad de inyectar colorantes u otros trazadores.
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54.
Gravity Recovery and Climate Experiment (GRACE) derived groundwater storage (GWS) data are compared with in-situ groundwater levels from five groundwater basins in Jordan, using newly gridded GRACE GRCTellus land data. It is shown that (1) the time series for GRACE-derived GWS data and in-situ groundwater-level measurements can be correlated, with R 2 from 0.55 to 0.74, (2) the correlation can be widely ascribed to the seasonal and trend component, since the detrended and deseasonalized time series show no significant correlation for most cases, implying that anomalous signals that deviate from the trend or seasonal behaviour are overlaid by noise, (3) estimates for water losses in Jordan based on the trend of GRACE data from 2003 to 2013 could be up to four times higher than previously assumed using estimated recharge and abstraction rates, and (4) a significant time-lagged cross correlation of the monthly changes in GRACE-derived groundwater storage and precipitation data was found, suggesting that the conventional method for deriving GWS from GRACE data probably does not account for the typical conditions in the study basins. Furthermore, a new method for deriving plausible specific yields from GRACE data and groundwater levels is demonstrated.  相似文献   
55.
56.
In the context of the EU-Project BALANCE () the regional climate model REMO was used for extensive calculations of the Barents Sea climate to investigate the vulnerability of this region to climate change. The regional climate model REMO simulated the climate change of the Barents Sea Region between 1961 and 2100 (Control and Climate Change run, CCC-Run). REMO on ~50 km horizontal resolution was driven by the transient ECHAM4/OPYC3 IPCC SRES B2 scenario. The output of the CCC-Run was applied to drive the dynamic vegetation model LPJ-GUESS. The results of the vegetation model were used to repeat the CCC-Run with dynamic vegetation fields. The feedback effect of the modified vegetation on the climate change signal is investigated and discussed with focus on precipitation, temperature and snow cover. The effect of the offline coupled vegetation feedback run is much lower than the greenhouse gas effect.  相似文献   
57.
Little is known about the Hadean and the Archean impact record on Earth. In the CT3 drill core from the Fig Tree Group of the northern Barberton Greenstone Belt, 17 spherule layer intersections occur, which, provide an outstanding new opportunity to gain insights into meteorite bombardment of the early Earth. CT3 spherules, as primary features, mostly exhibit textural patterns similar to those of the other Barberton spherule layers, but locally mineralogical and chemical compositional differences are observed, likely as a result of various degrees of alteration. The observed mineralogy of the spherule layers is of secondary origin and comprises K‐feldspar, phyllosilicates, carbonates, sulfides, and oxides, with the exception of secondary Ni‐Cr spinel that is of primary origin. Our petrographic investigations suggest alteration by K‐metasomatism, sericitization, silicification, and carbonatization. Siderophile element contents of bulk samples show significant enrichments in Ni (up to 2 wt%) and Ir (up to ~3 ppm), similar to previously studied Archean spherule layers. These values are indicative of the presence of a meteoritic component. On the other hand, lithophile and chalcophile element abundances indicate hydrothermal overprint on the CT3 samples; this may also have influenced the redistribution of the meteoritic component(s). Last, we group the CT3 spherule layers, which occur in three intervals (A, B, and C), according to their petrographic and geochemical features, which indicate evidence for at least three distinct impact events before tectonic overprint that affected the original deposits.  相似文献   
58.
In offshore waters of the German North Sea multiple stakeholder activity is increasing in both type and intensity. Newcomers such as wind farms make for additional claims and exclude, due to current legal constraints, other sectors, such as traditional fisheries. In this context, integrating marine aquaculture with designated wind farm areas might provide chances to combine two industries in the frame of a multiple-use concept. This paper takes up concerns and possible management framework requirements as expressed through interviews with the wind farm industry and the mussel harvesting sector when inquiring about such a multiple-use setting. The article closes with a discussion on two co-management strategies that might be appropriate for governing potential interacting wind farm–mariculture activities.  相似文献   
59.
Natural Resources Research - There are no available data about direct burkeite formation on the geothermal waters pipelines in Europe. Data about accompanying minerals of burkeite are also scarce....  相似文献   
60.
Zhang  Jiawen  Liesch  Tanja  Chen  Zhao  Goldscheider  Nico 《Hydrogeology Journal》2023,31(5):1197-1208

Karst areas contain valuable groundwater resources and high biodiversity, but are particularly vulnerable to climate change and human impacts. Land-use change is the cause and consequence of global environmental change. The releases of the Climate Change Initiative-Land Cover (CCI-LC) and World Karst Aquifer Map (WOKAM) datasets have made it possible to explore global land-use changes in karst areas. This paper firstly analyses the global karst land-use distribution in 2020, as well as the land-use transition characteristics between 1992 and 2020. Then, two indicators, proportion of land-use change and dominant type of land-use change, are proposed to identify the spatial characteristics of land-use change in global karst areas. Finally, three examples of land-use change in karst areas are analyzed in detail. Land-use types and proportions of the global karst areas from large to small are as follows: forest (31.78%), bare area (27.58%), cropland (19.02%), grassland (10.87%), shrubland (7.21%), wetland (1.67%), ice and snow (1.16%) and urban (0.71%). The total area of global karst land-use change is 1.30 million km2, about 4.85% of global karst surface. The land-use change trend of global karst is dominated by afforestation, supplemented by scattered urbanization and agricultural reclamation. The tropical climate has a higher intensity of land-use change. Regions of agricultural reclamation are highly consistent with the population density. These results reflect the impact of human activities and climate change on land-use changes in global karst areas, and serve as a basis for further research and planning of land resource management.

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