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921.
Ngin Chanrith Grayman Jesse Hession Neef Andreas Sanunsilp Nichapat 《Natural Hazards》2020,103(1):299-316
Natural Hazards - Drawing on interviews with Cambodian and Thai communities in Auckland, New Zealand, this paper examines the role of Buddhist temples in disaster preparedness, response and... 相似文献
922.
923.
Seyedsina Yousefianmoghadam Mingming Song Mohammad Ebrahim Mohammadi Brittany Packard Andreas Stavridis Babak Moaveni Richard L. Wood 《地震工程与结构动力学》2020,49(9):924-945
This paper discusses the dynamic tests of a two-story infilled reinforced concrete (RC) frame building using an eccentric-mass shaker. The building, located in El Centro, CA, was substantially damaged prior to the tests due to the seismic activity in the area. During the testing sequence, five infill walls were removed to introduce additional damage states and to investigate the changes in the dynamic properties and the nonlinear response of the building to the induced excitations. The accelerations and displacements of the structure under the forced and ambient vibrations were recorded through an array of sensors, while lidar scans were obtained to document the damage. The test data provide insight into the nonlinear response of an actual building and the change of its resonant frequencies and operational shapes due to varying damage levels and changes of the excitation amplitude, frequency, and orientation. 相似文献
924.
GPCC's new land surface precipitation climatology based on quality-controlled in situ data and its role in quantifying the global water cycle 总被引:10,自引:3,他引:10
Udo Schneider Andreas Becker Peter Finger Anja Meyer-Christoffer Markus Ziese Bruno Rudolf 《Theoretical and Applied Climatology》2014,115(1-2):15-40
In 1989, the need for reliable gridded land surface precipitation data sets, in view of the large uncertainties in the assessment of the global energy and water cycle, has led to the establishment of the Global Precipitation Climatology Centre (GPCC) at Deutscher Wetterdienst on invitation of the WMO. The GPCC has calculated a precipitation climatology for the global land areas for the target period 1951–2000 by objective analysis of climatological normals of about 67,200 rain gauge stations from its data base. GPCC's new precipitation climatology is compared to several other station-based precipitation climatologies as well as to precipitation climatologies derived from the GPCP V2.2 data set and from ECMWF's model reanalyses ERA-40 and ERA-Interim. Finally, how GPCC's best estimate for terrestrial mean precipitation derived from the precipitation climatology of 786 mm per year (equivalent to a water transport of 117,000 km3) is fitting into the global water cycle context is discussed. 相似文献
925.
Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model 总被引:8,自引:1,他引:8
HE Chunyang SHI Peijun CHEN Jin Li Xiaobing PAN Yaozhong LI Jing LI Yuechen & LI Jinggang Key Laboratory of Environmental Change Natural Disaster Ministry of Education of China Beijing Normal University College of Resources Science & Technology Beijing Normal University Beijing China 《中国科学D辑(英文版)》2005,48(11):1979-1989
Models of land use change are useful tools for un-derstanding the analysis of the cause and conse-quences of land use changes, assessing the impacts of land use system on ecological system and supporting land use planning and policy[1,2]. Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are regarded as one of the good ways to un-derstand the interactive mechanism between land use system and ecological system[3―10… 相似文献
926.
Many glaciers in alpine regions are currently rapidly receding and thinning at historically unobserved rates causing changes in the velocity field and in normal and shear stresses affecting the surface expression of structures within the ice. We studied the distribution of brittle and ductile structures at the surface of Pasterze Glacier during a 14-year period by analysing orthophotos and digital elevation models of five stages (1998, 2003, 2006, 2009 and 2012). A structural glaciological mapping key was applied. Normal faults, strike-slip faults, en échelon structures (systematic stepping of fractures), thrust faults, and band ogives were distinguished. Results indicate substantial deceleration and glacier thinning in 1998–2012. Glacier thinning was not homogenous over time related to the uneven distribution of supraglacial debris causing differential ablation or the selective ablation effects of subglacial water channels. Peculiar supraglacial features observed are circular collapse structures with concentric crevasses which form when the ice between the surface and the roof of water channels decreases. The total length of brittle structures increased from 38.4 km to 56.9 km whereas the extent of the glacier tongue decreased by 25%. The fracture density doubled from 0.009 to 0.018 m/m2. Areas of the glacier tongue which were up to 100 m away from the nearest brittle structure increased by 16%. The visual appearance of thrust faults shifted upglacier due to decreasing glacier velocity causing horizontal shortening or due to exhumation of faults that did not previously extend to the surface. A large number of brittle structures are progressively independent from glacier motion. Our study suggests that glacier tongues which are in a state of rapid decay and thinning are prone to fracturing due to normal fault formation and glacier disintegration. Water further increases ablation rates substantially if rather large amounts drain through supra-, en- or subglacial water channels. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. 相似文献
927.
Dan Lei Jia Liu Junwei Zhang Andreas Lorke Shangbin Xiao Yuchun Wang Wei Wang Ye Li 《洁净——土壤、空气、水》2019,47(9)
Four field campaigns are carried out to quantify the methane (CH4) oxidation rate in Xiangxi Bay (XXB) of the Three Gorges Reservoir (TGR), China. The water depth of the sampling site varied from 13 to 30 m resulting from the water level fluctuation of the TGR. The CH4 oxidation rates are measured in situ as the decline of dissolved CH4 concentration versus time in incubated, and those rates. The CH4 oxidation rates range from 1.18 × 10?3 to 3.69 × 10?3 µmol L?1 h?1, with higher values and stronger variation during summer. A static floating chamber method is used to measure CH4 emitted to the atmosphere resulting in an annual mean flux of 4.79 µmol m?2 h?1. The CH4 emission rate is significantly negatively correlated with the water level. The results show that a large fraction of CH4 is consumed in the water column with a range of 28.97–55.90 µmol m?2 h?1, accounting for ≈69–98% of the total CH4 input into the water column, and more than 90% is consumed outside the summer, when the water level is lowest. Water depth, which is dominated by water level of the TGR, is a potentially important driver for CH4 oxidation and atmospheric emission in the tributary bay. 相似文献
928.
Kamil Vrana Stanislav Rapant Dušan Bodiš Karol Marsina Blanka Maňkovská Ján ?urlík Peter Šef?ík Jozef Daniel Ladislav Lu?ivjanský Jaroslav Lexa Silvester Pramuka 《Journal of Geochemical Exploration》1997,60(1):7-37
The Geochemical Atlas of Slovak Republic (49,036 km2) at a scale of 1 : 1,000,000 was compiled during 1991–1995 together with maps of associated geochemical and ecological features at a scale of 1 :200,000. Investigations were aimed at the evaluation of concentrations and distributions of Al, As, Ba, Be, Ca, Ce, Co, Cd, Cs, Cr, Cu, Fe, Ga, Hg, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sb, Se, Sn, Sr, Th, U, V, W, Y, Zn, Zr in groundwater (16,359 samples), stream sediments (24,422 samples), rocks (3839 samples), soils (9892 samples from 4946 profiles; A and C horizons of each profile were sampled) and forest biomass (the foliage of the forest tree species from 3063 plots was sampled). In groundwater field measurements of temperature, pH, conductivity, dissolved O2, acidity, alkalinity were done. The evaluation was oriented to the natural radioactivity of the Slovak territory as follows: rocks (K, U, Th, Utot and dose rate, 15,573 reference spectrometric points), radon risk and water (Unat, 226Ra, 222Rn; 5271 samples). The main objective of the Geochemical Atlas was to construct single-component maps showing concentrations of chemical elements, compounds and measured parameters in the researched media of Slovakia at a scale of 1 : 1,000.000 and to create interactive databases of chemical composition and/or measured parameters of groundwater, biomass, rocks, soils, stream sediments and natural radioactivity, for the entire territory of the Slovak Republic. The single-component maps are not constructed in the part ‘Rocks’, where all the main rocks types of Slovakia are presented in the ‘Map of lithogeochemical rock types of Slovakia at a scale of 1: 500,000’. The edition of six atlases has been planned. In 1997 the first three atlases will appear (Groundwater, Biomass, Natural Radioactivity). Publishing of last three atlases (Rocks, Soils, Stream Sediments) is planned for 1998. Since the analytical works on stream sediments were finished during 1997, it was not possible to present here the results of that part of the Geochemical Atlas. 相似文献
929.
Józef Lis Anna Pasieczna Ryszard Strzelecki Stanis?aw Wo?kowicz Pawe? Lewandowski 《Journal of Geochemical Exploration》1997,60(1):39-53
In 1990 the Polish Geological Institute initiated geochemical mapping of the country aimed at determining the actual conditions of chemistry in the Earth's surficial environments (soils, water sediments, and surficial waters as well) and sea-floor deposits in the Polish economic sector of the Baltic Sea. The geochemical mapping on different scales covered the entire area of the country and selected more important urban agglomerations and industrial districts. Approximately 15,100 samples of soils, 16,200 samples of fresh water sediments, 14,600 samples of surface waters and 467 samples of marine deposits were collected and analysed. A list of geochemical atlases published by the Polish Geological Institute is presented. Investigation of the distribution of radionuclides (natural and artificial) has been done since 1992. Concentrations of U, Th, K, post-Chernobyl Cs and γ dose rate were measured. Approximately 20,000 points covering the whole country were measured. More detailed mappings were executed in the areas polluted by Cs. 相似文献
930.