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21.
Rural heritage that involves agricultural heritage could be critical to enhancing community identity through a conservational approach. The purpose of this research is to develop conservational methods for rural heritage that include agricultural heritage areas through the use of ecomuseums. To conduct the research, we first reviewed the concepts of ecomuseum and rural heritage. Secondly, we defined the concept of the Korean rural ecomuseum by taking into consideration the concept defined by Riviere, Globally Important Agricultural Heritage Systems (GIAHS), the rural heritage policy of Europe, and the agricultural heritage systems of Korea. Thirdly, we also describe methods that are applicable to Korean rural ecomuseums, which include type classification and components. Finally, we applied the ecomuseum concept to two pilot models in the Cheongsando and Gurae areas, both Korea Important Agricultural Heritage System (KIAHS) sites. We conclude that it is desirable to expand the range of targets for conservation from agricultural heritage to rural heritage areas. From this point of view, the rural ecomuseum can be a highly valuable tool that can help preserve agricultural heritage sites and neighboring areas. Furthermore, the ecomuseum can enhance community identities, and strengthen local economies.  相似文献   
22.
Phosphorus (P) species concentrations in 0–2 cm surface sediment layer were investigated monthly from November 2001 to December 2002 at the bay, channel and open sea stations in the middle Adriatic. Modified SEDEX method was used for inorganic phosphorus species determination [P in biogenic (P-FD), authigenic (P-AUT), detrital apatite (P-DET) and P adsorbed on to iron oxides and hydroxides (P–Fe)], and organic phosphorus (P-ORG). P-FD, P-AUT and P-DET concentration ranges (1.5–5.4, 0–2.7 and 0.4–3.4 μmol g−1, respectively) were similar at all stations, and showed no obvious common trend of seasonal changes. P–Fe ranged from 1.9 to 11.9 μmol g−1 with the highest values at bay station and higher seasonal oscillations than other inorganic P forms. P-ORG ranged from 0.3 to 18.7 μmol g−1 with higher concentrations at stations of fine-sized sediments and showed increased concentrations in warm part of the year at all stations. Correlation between concentrations of P–Fe in the surface sediment layer and orthophosphate sediment-water interface concentration gradients at bay and channel stations indicated to P–Fe importance in the orthophosphate benthic flux. For the bay station, linkage between sediment P-ORG and chlorophyll a concentrations, primary production and microzooplankton abundance was established, indicating a 1 month delay of sediment response to production fluctuations in the water column.  相似文献   
23.
Uranium isotopes were measured in waters and suspended particulate matters (SPM) of the main channel of Yellow River, China that were sampled during four field trips between August 2005 and July 2006. The results show that the concentration of dissolved U (2.04–7.83 μg/l) and the activity ratio of 234U/238U (1.36–1.67) are much higher than the average U concentrations and activity ratios of global major rivers. Mass balance calculations using the results of simulated experiments and measurement data show that the section of the Yellow River between Lanzhou and Sanmenxia has its dissolved U derived from two sources: suspended sediments (68%) and groundwater/runoff from loess deposits (32%). Both sources are related to the heavy erosion of the Chinese Loess Plateau.  相似文献   
24.
The Penn State/ NCAR Mesoscale Model (MM5) is used to simulate the precipitation event that oc-curred during 1-2 May 1994 to the south of the Yangtze River. In five experiments the Kain-Fritsch scheme is made use of for the subgrid-scale convective precipitation, but five different resolvable-scale microphysical parameterization schemes are employed. They are the simple super-saturation removal scheme, the warm rain scheme of Hsie et al. (1984), the simple ice scheme of Dudhia (1989), the complex mixed-phase scheme developed by Reisner et al. (1993). and the GSFC microphysical scheme with graupel. Our interest is how the various resolvable-scale schemes affect the domain-averaged precipitation, the pre-cipitation distribution, the sea level pressure, the cloud water and the cloud ice.Through a series of experiments about a warm sector rainfall case, results show that although the dif-ferent resolvable-scale scheme is used, the differences of the precipitation characteristics among all five runs are not very obvious. However, the precipitation is over-predicted and the strong mesoscale low is produced by the simple super-saturation removal scheme. The warm rain scheme with the inclusion of condensation and evaporation under-predicts the precipitation and allows the cloud water to reach the 300 hPa level The scheme of the addition of graupel increases the resolvable-scale precipitation by about 20%–30%. The inclusion of supercooled liquid water in the grid-scale scheme does not affect significantly the results.  相似文献   
25.
The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. Towards late Pliocene, evaporative conditions developed with formation of gypsum, halite, celestite, mirabilite and bloedite. Continued deformation through Pleistocene developed a series of NW- SE trending domes and troughs. This setting continued to exert a controlling influence on basin and brine evolution and the progressive development of sulfate to chloride brines as, dry conditions intensified in late Pleistocene, at the end of which, extensive flat floors were formed in Dalangtan, Qarhan and other playas.The, model, which was set up based on the synthetic analyses, divides the fluctuating palaeoclimate since 750ka,B. P. into 11 warm and humid stages and 10 dry and cold stages. The water of the lakes evaporated during the dry-cold periods and were freshened during the warm-humid periods  相似文献   
26.
The construction and the optical design as well as the controlling electronic device and the spectrum recording of the new horizontal solar telescope with the spectrograph of the Astronomical Institute of Slovak Academy of Sciences are described. Also some of its adjustments and improvements are briefly mentioned.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   
27.
The purpose of the article is to examine the ways in which regional geography textbooks are used in elementary education, using north-west Bohemia as a case study. The authors analysed 18 textbooks published since the beginning of the 20th century, in two steps: (1) the construction of geographical names frequency maps indicating which parts of the case region are accentuated or suppressed in individual textbooks, and (2) a qualitative analysis of the textbooks’ content. The study revealed that a complex image of north-west Bohemia in interwar period in Czechoslovakia and in the period of accession to the European Union is presented in the textbooks. The textbooks published during communist era are imbued with the adoration of local industries, whereas those published later, in the period of political and socio-economic transformation, accentuate the risks of excessive environmental exploitation. At any time since the beginning of the 20th century, the places and regions that represent the values preferred by the governing ideology are emphasized within the studied textbooks. Thus, the geography textbooks, that reflect the society-wide discourse, disseminate not only knowledge but also dominant values. In this way, a desired image of reality is created that legitimates the aims and stances of those in power.  相似文献   
28.
Zhou  Bo  Ku  Quan  Li  Changheng  Wang  Huabin  Dong  Youkou  Cheng  Zhuang 《Acta Geotechnica》2022,17(8):3195-3209

This paper investigates the particle breakage behaviour of a carbonate sand based on single-particle compression experiments with in situ X-ray microtomography scanning (μCT) and a combined finite–discrete element method (FDEM). Specifically, X-ray μCT is applied to extract the information on grain morphology and intra-particle pores of carbonate sand particles to establish an FDEM model. The model is first calibrated by comparing the simulation results of two carbonate sand grains with the corresponding single-particle compression experiment results and then applied to model the stress evolution, cracking propagation and failure of other carbonate sand particles under single-particle compression. To study the influence of intra-particle pores, FDEM modelling of carbonate sands with completely filled intra-particle pores is also performed. The particle strength of carbonate sands both with and without pore filling is found to follow a Weibull distribution, with that of the sand with pore filling being considerably higher. This behaviour is associated with lower stress concentration, resulting in later crack development in the pore-filled sand than in the sand without pore filling. The cracks are found to usually pass through the intra-particle pores. Consequently, a larger proportion of particles fail in the fragmentation mode in the sand without pore filling.

  相似文献   
29.
王库  丁洪 《福建地理》2012,(3):20-25
以福州市晋安河沿线区域为研究对象,采集区内地表径流样品,通过分析径流水样中全氮、全磷浓度,采用普通克里格法分析了地表径流中全氮、全磷的空间分布特征.结果表明,全氮是地表径流的主要污染物质,全磷除少部分地段超标外,总体上不构成污染;全氮、全磷的半方差函数用球状模型拟合的最好,其空间分布表现为各向同性;地表径流中全氮污染主要集中于管理条件落后的居民区、餐饮业集中的娱乐场所以及非城市主干道路.地表径流中的全磷主要分布在餐饮业集中区域及管理落后的住宅小区.福州城市地表径流的氮磷污染主要来自于居民的日常生活排污.  相似文献   
30.
Ubiquitous post-Variscan dolomites occur in Zn–Pb–Cu veins at the Nízký Jeseník Mountains and the Upper Silesian Basin (Lower and Upper Carboniferous siliciclastics at the eastern part of the Bohemian Massif). Crush–leach, stable isotope (oxygen and carbon) and microthermometry analysis of the fluid inclusions in dolomites enable understanding the geochemistry, origin and possible migration pathways of the fluids. Homogenisation temperatures of fluid inclusions range between 66 and 148°C, with generally higher temperatures in the Nízký Jeseník Mountains area than in the Upper Silesian Basin. The highest homogenisation temperatures (up to 148°C) have been found near major regional faults and the lowest in a distant position or at higher stratigraphic levels. Highly saline (16.6–28.4 eq. wt% NaCl) H2O–NaCl–CaCl2 ± MgCl2 fluids occur in inclusions. Na–Cl–Br systematics of trapped fluids and a calculated oxygen isotopic fluid composition between ?0.9 and +3.0‰ V-SMOW indicate that the fluid was derived from evaporated seawater. Stable isotopic modelling has been used to explain stable isotopic trends. Isotopic values (δ13C = ?6.0/+2.0‰ V-PDB, δ18O = +15.5/+22.5‰ V-SMOW of dolomites) resulted from fractionation and crystallisation within an open system at temperatures between 80 and 160°C. Rock-buffering explains the isotopic composition at low w/r ratios. Organic matter maturation caused the presence of isotopically light carbon in the fluids and fluid–rock interactions largely controlled the fluid chemistry (K, Li, Br and Na contents, K/Cl, I/Cl and Li/Cl molar ratios). The fluid chemistry reflects well the interaction between the fluid and underlying limestones as well as with clay- and organic-rich siliciclastics. No regional trends in temperature or fluid geochemistry favour a fluid migration model characterised by an important vertical upward migration along major faults. A permeable basement and fractured sedimentary sequence enhanced the general nature of the fluid system. Fluid characteristics are comparable with the main post-Variscan fluid flow systems in the Polish (Cracow-Silesian ore district) and German sedimentary basins.  相似文献   
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