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111.
Ecosystem-based marine spatial management: Review of concepts, policies, tools, and critical issues 总被引:1,自引:0,他引:1
Stelios Katsanevakis Vanessa Stelzenmüller Andy South Thomas Kirk Sørensen Peter J.S. Jones Sandy Kerr Fabio Badalamenti Christos Anagnostou Patricia Breen Guillem Chust Giovanni D’Anna Mike Duijn Tatiana Filatova Fabio Fiorentino Helena Hulsman Kate Johnson Aristomenis P. Karageorgis Ingrid Kröncke Simone Mirto Carlo Pipitone Susan Portelli Wanfei Qiu Henning Reiss Dimitris Sakellariou Maria Salomidi Luc van Hoof Vassiliki Vassilopoulou Tomás Vega Fernández Sandra Vöge Anke Weber Argyro Zenetos Remment ter Hofstede 《Ocean & Coastal Management》2011,54(11):807-820
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes. 相似文献
112.
Arsenic in shallow groundwater of Bangladesh: investigations from three different physiographic settings 总被引:1,自引:0,他引:1
M. Aziz Hasan K. Matin Ahmed Ondra Sracek Prosun Bhattacharya Mattias von Brömssen Sandra Broms Johan Fogelström M. Lutful Mazumder Gunnar Jacks 《Hydrogeology Journal》2007,15(8):1507-1522
Occurrences of arsenic (As) in the Bengal Basin of Bangladesh show close relationships with depositional environments and sediment textures. Hydrochemical data from three sites with varying physiography and sedimentation history show marked variations in redox status and dissolved As concentrations. Arsenic concentration in groundwater of the Ganges Flood Plain (GFP) is characteristically low, where high Mn concentrations indicate redox buffering by reduction of Mn(IV)-oxyhydroxides. Low DOC, \( {\text{HCO}}^{ - }_{3} \), \( {\text{NH}}^{ + }_{4} \) and high \( {\text{NO}}^{ - }_{3} \) and \( {\text{SO}}^{{2 - }}_{4} \) concentrations reflect an elevated redox status in GFP aquifers. In contrast, As concentration in the Ganges Delta Plain (GDP) is very high along with high Fe and low Mn. In the Meghna Flood Plain (MFP), moderate to high As and Fe concentrations and low Mn are detected. Degradation of organic matter probably drives redox reactions in the aquifers, particularly in MFP and GDP, thereby mobilising dissolved As. Speciation calculations indicate supersaturation with respect to siderite and vivianite in the groundwater samples at MFP and GDP, but groundwater in the GFP wells is generally supersaturated with respect to rhodochrosite. Values of log PCO2 at MFP and GDP sites are generally higher than at the GFP site. This is consistent with Mn(IV)-redox buffering suggested at the GFP site compared to Fe(III)-redox buffering at MFP and GDP sites. 相似文献
113.
M. Ahmad M. K. Ansari Rajesh Singh L. K. Sharma T. N. Singh Sandra Pires 《Journal of the Geological Society of India》2018,91(4):467-474
Alkali-aggregate reactivity (AAR) involves a reaction between the pore solution of concrete and certain minerals found in some aggregates. To assess the potential AAR various physical and chemical tests are available and extensively used. The petrographic examination is the initial assessment that decides the further investigation for potential reactivity of an aggregate. A chemical approach is another option to assess the aggregate for potential AAR. The accelerated mortar bar method and concrete prism tests are other very important tests for determination of potential AAR of aggregates samples. However, a combination of the results of all the techniques provides most reliable results for potential AAR in aggregates. Moreover, each test represents the stepwise investigation and provides the decision for the test of next approach. Petrographic examination and chemical test methods are the quick decision-making methods for the estimation of potential AAR. In some cases, by these two methods, the aggregate can be selected and rejected confidently. However, for critical values or doubtful aggregates, further tests are necessary to develop a higher confidence level of the results. The present study comprises of the assessment of the alkali-reactivity of siliceous and carbonate aggregates using petrographic and chemical approaches. X-ray diffraction analysis was used as a complementary method to the petrographic evaluation. Moreover, under chemical approach, two separate test methods were used for siliceous and carbonate aggregates. The study also included a comparison between the petrographic examination and chemical analysis for the same aggregate samples and found significant results. 相似文献
114.
This paper presents a land use and land cover (LULC) classification approach that accounts landscape heterogeneity. We addressed this challenge by subdividing the study area into more homogeneous segments using several biophysical and socio-economic factors as well as spectral information. This was followed by unsupervised clustering within each homogeneous segment and supervised class assignment. Two classification schemes differing in their level of detail were successfully applied to four landscape types of distinct LULC composition. The resulting LULC map fulfills two major requirements: (1) differentiation and identification of several LULC classes that are of interest at the local, regional, and national scales, and (2) high accuracy of classification. The approach overcomes commonly encountered difficulties of classifying second-level classes in large and heterogeneous landscapes. The output of the study responds to the need for comprehensive LULC data to support ecosystem assessment, policy formulation, and decision-making towards sustainable land resources management. 相似文献
115.
We present microstructural and chemical analyses of chemically zoned and recrystallized plagioclase grains in variably strained samples of a naturally deformed anorthosite–leucogabbro, southern West Greenland. The recorded microstructures formed in the presence of fluids at mid-crustal conditions (620–640 °C, 7.4–8.6 kbar). Recrystallized plagioclase grains (average grain size 342 μm) with a random crystallographic orientation are volumetrically dominant in high-strain areas. They are characterized by asymmetric chemical zoning (An80 cores and An64 rims) that are directly associated with areas exhibiting high amphibole content and phase mixing. Analyses of zoning indicate anisotropic behaviour of bytownite plagioclase with a preferred replacement in the $ \left\langle {0 10} \right\rangle $ direction and along the (001) plane. In areas of high finite strain, recrystallization of plagioclase dominantly occurred by bulging recrystallization and is intimately linked to the chemical zoning. The lack of CPO as well as the developed asymmetric zoning can be explained by the activity of grain boundary sliding accommodated by dissolution and precipitation creep (DPC). In low-strain domains, grain size is on average larger and the rim distribution is not related to the inferred stress axes indicating chemically induced grain replacement instead of stress-related DPC. We suggest that during deformation, in high-strain areas, pre-existing phase mixture and stress induced DPC-caused grain rotations that allowed a deformation-enhanced heterogeneous fluid influx. This resulted in local plagioclase replacement through interface-coupled dissolution and precipitation and chemically induced grain boundary migration, accompanied by bulging recrystallization, along with neocrystallization of other phases. This study illustrates a strong interaction and feedback between physical and chemical processes where the amount of stress and fluids dictates the dominant active process. The interaction is a cause of deformation and external fluid infiltration with a result of strain localization and chemical re-equilibration at amphibolite facies conditions. 相似文献
116.
Rainer Altherr Christian Soder Sandra Panienka Daniel Peters Hans-Peter Meyer 《Contributions to Mineralogy and Petrology》2013,166(5):1323-1334
A new occurrence of Mn-rich rocks was discovered within the high-pressure/low-temperature metamorphic rocks on the Palos peninsula of Syros (Greece). Near the summit of Mount Príonas, a meta-conglomerate consists of calcite (~63 wt%), pink manganian phengite, blue–purple manganian aegirine–jadeite, microcline, albite and quartz. In addition, it contains abundant braunite-rich aggregates (up to ~1.5 cm in diameter) that include hollandite [(Ba0.98–1.02K<0.01Na<0.02Ca<0.03) (Mn 1.02–1.52 3+ Fe 0.38–0.88 3+ Ti0.29–0.92Mn 5.11–5.76 4+ )O16], barite and manganian hematite. Due to metamorphic recrystallization and deformation, the contacts between clasts and matrix are blurred and most clasts have lost their identity. In back-scattered electron images, many aegirine–jadeite grains appear patchy and show variable jadeite contents (Jd10–67). These pyroxenes occur in contact with either quartz or albite. Manganian phengite (3.41–3.49 Si per 11 oxygen anions) is of the 3T type and contains 1.4–2.2 wt% of Mn2O3. At the known P–T conditions of high-pressure metamorphism on Syros (~1.4 GPa/ 470 °C), the mineral sub-assemblage braunite + quartz + calcite (former aragonite) suggests high oxygen fugacities relative to the HM buffer (+7 ≤ ?fO2 ≤ + 17) and relatively high CO2 fugacities. The exact origin of the conglomerate is not known, but it is assumed that the Fe–Mn-rich and the calcite-rich particles originated from different sources. Braunite has rather low contents of Cu (~0.19 wt%) and the concentrations of Co, Ni and Zn are less than 0.09 wt%. Hollandite shows even lower concentrations of these elements. Furthermore, the bulk-rock compositions of two samples are characterized by low contents of Cu, Co and Ni, suggesting a hydrothermal origin of the manganese ore. Most likely, these Fe–Mn–Si oxyhydroxide deposits consisted of ferrihydrite, todorokite, birnessite, amorphous silica (opal-A) and nontronite. Al/(Al + Fe + Mn) ratios of 0.355 and 0.600 suggest the presence of an aluminosilicate detrital component. 相似文献
117.
A fundamental question in arid land management centers on understanding the long‐term effects of fire on desert ecosystems. To assess the effects of fire on surface topography, soil roughness, and vegetation, we used terrestrial (ground‐based) LiDAR to quantify the differences between burned and unburned surfaces by creating a series of high‐resolution vegetation structure and bare‐earth surface models for six sample plots in the Grand Canyon‐Parashant National Monument, Arizona. We find that 11 years following prescribed burns, mound volumes, plant heights, and soil‐surface roughness were significantly lower on burned relative to unburned plots. Results also suggest a linkage between vegetation and soil mounds, either through accretion or erosion mechanisms such as wind and/or water erosion. The biogeomorphic implications of fire‐induced changes are significant. Reduced plant cover and altered soil surfaces from fire likely influence seed residence times, inhibit seed germination and plant establishment, and affect other ecohydrological processes. Published in 2012. This article is a US Government work and is in the public domain in the USA. 相似文献
118.
de Souza Luciana Sandra Bastos Silva Maiara Tatiane Lima Alba Elisiane de Moura Magna Soelma Beserra da Cruz Neto José Francisco de Souza Carlos André Alves da Silva Thieres George Freire 《Theoretical and Applied Climatology》2022,149(1-2):593-602
Theoretical and Applied Climatology - Analysing alternative methods for estimating reference evapotranspiration (ET0) is essential for improving the management of water resources, especially where... 相似文献
119.
The surface heat flux of a planet is an important parameter to characterize its internal activity and to determine its thermal evolution. Here we report on a new method to constrain the surface heat flux of Mars during the Hesperian. For this, we explore the consequences for the martian surface heat flux from a recently presented new hypothesis for the formation of Aram Chaos (Zegers, T.E., Oosthoek, J.H.P., Rossi, A.P., Blom, J.K., Schumacher, S. [2010]. Earth Planet. Sci. Lett. 297, 496-504. doi:10.1016/j.epsl.2010.06.049.). In this hypothesis the chaotic terrain is thought to have formed by melting of a buried ice sheet. The slow sedimentation and burial of the ice sheet led to an increased thermal insulation of the ice and subsequently to a temperature increase high enough to trigger melting and the formation of the subsurface lake. As these processes highly depend on the thermal properties of the subsurface and especially on the surface heat flux, it is possible to constrain the latter by using numerical simulations. Based on the hypothesis for the formation of Aram Chaos, we conducted an extensive parameter study to determine the parameter settings leading to sufficient melting of the buried ice sheet. We find that the surface heat flux in the Aram Chaos region during the Hesperian was most likely between 20 and 45 mW m−2 with a possible maximum value of up to 60 mW m−2. 相似文献
120.
Observations of hourly wind speeds and directions were taken over a 56-day period in summer 1978, at the 3,000 m ground level near an INSTAAR mountain research site on the east slope of the Front Range, Colorado Rockies. During nearly calm weather, which persisted for longer periods than normal in summer 1978, the pattern of diurnal wind variations resembles results from other mountain studies of wind along high mountain slopes. However, timing of high wind speeds during the daily cycle is not readily explainable, although hypotheses can be offered. Results of this study can assist in interpretations of forest clearing microclimates at high elevations in the mountains and in important air quality questions (e.g., precipitation pH) in the Rocky Mountains. 相似文献