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J. Germán Rodríguez Oihana Solaun María Jesús Belzunce Segarra J. Ignacio García Alonso Victoriano Valencia 《Marine pollution bulletin》2010,60(1):139-642
Tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were measured in surficial sediments at, the ports of Pasaia and Bilbao, together with other mid- and small-size harbours of the Basque Country (northern Spain), in 2007-2008. The highest values of the sum of the three measured butyltin species (3523-3640 ng g−1, as Sn) were found at sampling stations near to shipyards located within the port of Pasaia. The highest value of TBT concentration (3143 ng g−1, as Sn) was found at the marina of Getxo, in the port of Bilbao. The degree of TBT degradation varied greatly between sampling stations, being found to be generally higher in those sediments with higher values of redox potential and lower values of TBT concentration (normalized by organic matter content). 相似文献
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The use of AMBI and M-AMBI in benthic quality assessments, within the European Water Framework Directive (WFD), has increased dramatically in recent years. M-AMBI is a multivariate tool, which incorporates AMBI, richness and Shannon diversity within the assessment. The response of this approach to different human pressures in coastal and estuarine waters has been investigated for the Basque Country (Northern Spain). In this contribution, several paradigmatic examples of these applications to different water bodies are presented. The time-series extend to samples collected between 1995 and 2007, showing the evolution of M-AMBI values under different pressures, i.e. urban and industrial discharges, dredging and disposal of sediments, and engineering works (such as land reclamation or marina construction), and, in addition, for illustrating the benthic quality recovery after positive actions have been undertaken, i.e. the removal of point-source discharges or water treatment programmes. In most cases, M-AMBI responds to these pressures as expected, with decreases in the ecological status immediately following the pressure. Conversely, when a pressure is removed, the recovery takes between 2 and 15 years, depending upon the intensity of the pressure and the characteristics of the water body. M-AMBI has been intercalibrated previously in coastal waters. After intercalibration in transitional waters, M-AMBI will be able to be used in the integrative quality assessment of European water bodies. 相似文献
24.
I. Arrate J. M. Sanchez-Perez I. Antiguedad M. A. Vallecillo V. Iribar M. Ruiz 《Environmental Geology》1997,30(3-4):257-265
As a result of diverse changes in land use and in water-resource management in the high basin of the Zadorra River (Basque
Country), an important loss of water resources and an intense contamination by nitrogen compounds has taken place. The purpose
of this paper is to detail the land transformations that have taken place on the aquifer since the 1950s: increase of drainage
network, change from dry to irrigated farming, and diversion of rivers at the aquifer unit inlet. Furthermore, we analyze
the impact of these transformations on the hydrodynamics and water quality of this aquifer system.
Received: 12 January 1996 · Accepted: 10 March 1996 相似文献
25.
河南范县ML4.3级地震前后重力异常探讨 总被引:1,自引:2,他引:1
分析研究范县地震前后豫鲁测网的重力场与点值变化特征后发现:地震发生在重力场上升过程中,且地震震中位于重力等值线负值区到正值区的过渡带上,重力点值在时间上具有同步性,而震后重力场的下降有可能是新的异常。 相似文献
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Genevieve Simpson 《The Australian geographer》2010,41(3):403-423
Landcare groups in Australia work to increase biodiversity, eliminate invasive species and promote sustainable land-use practices. With the implementation of the Rudd government's ‘Caring for our Country’ policy during 2008–09, financial and organisational resources available to these groups diminished. This paper examines whether the National Landcare Program's initial intentions—that agency support could be provided to ‘kick-start’ the community groups into action with the Landcare groups quickly becoming independent bodies—are ultimately realistic. The results show that the majority of Landcare groups continue to be reliant on government-sourced funding and Landcare facilitators, and that those groups which do not have access to support have reduced their activity levels accordingly. Landcare groups were suffering from a reduced volunteer base, with static or decreasing numbers of participants, an inability to set regular meetings and a lack of volunteers to take up leadership positions. The reliance of Landcare groups on government support suggests that Landcare was an unsuccessful form of state-sponsored community participation, making Landcare groups similar to other volunteer organisations in terms of their functional characteristics and reliance on externally sourced funds. 相似文献
29.
The 2015 Paris Agreement was adopted in a geopolitical context that is very different from the post-Cold War era when the Climate Convention was negotiated. This new global climate deal responds to a more fragmented and multipolar world signified by the rise of major economies in the South. This paper examines the geopolitical landscape in which the Paris Agreement is enacted and implemented. We conduct a discursive analysis of the Nationally Determined Contributions submitted by parties to the Paris Agreement. We ask what policy discourses emerge in these national climate plans, which states cluster around them and how they compare to UNFCCC annex, geographical location, income group, and negotiation coalitions. Our findings suggest that liberal environmentalism retains a strong hold over the political imagination in the post-Paris landscape. However, we see points of diffraction and tensions that might give rise to conflict. While liberal environmentalism is only challenged in Nationally Determined Contributions from the global South, we conclude that conventional geopolitical patterns only partly explain the formation of discourse coalitions. In the Paris Agreement’s implementation stage discursive struggles are likely to become increasingly prominent. Discourse analysis facilitates understanding of disagreements on the Paris rulebook and the global stocktake. 相似文献
30.
The regional study of hydrodynamic characteristics of karstic aquifers is challenging because of the great variety of lithology and the structural complexity found in carbonate formations. In order to improve this situation, a combined approach of time series and stochastic analyses was adopted to assess the hydrodynamic behaviour of the karstic aquifers. To achieve this, daily flow rates of 20 springs were taken from the 11 most significant aquifer units of the Basque Country. The results demonstrate the presence of memory effects, which modulated the input rainfall for short‐, medium‐ and long‐term storage capacity, resulting in hydrodynamic properties such as system memory, response time and mean delay between input and output. They reflect the storage and the manner in which these are filled and emptied, thus indicating the karstification of the aquifer. Likewise, the hydrodynamic and hydraulic classification obtained from the stochastic analysis provides a complementary approach to characterize the hydraulic behaviour of the studied karstic aquifers. The discussed examples indicate that this approach provides an excellent method to research hydrological karst systems. It is also shown that the use of hydrologic time series, alone, does not lead to a satisfactory classification of the hydrodynamic characteristics. Therefore, the general approach to hydrological regionalization in karst areas should take into account the structural complexity, heterogeneity of the lithology and the degree of karstification. Only in this case will the regionalization be physically founded, leading to a regional understanding of the hydrodynamic characteristics and flow conditions in a karst aquifer. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献