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41.
We examine the effects of natural disasters on income and investment in China. Using macroeconomic province-level data and the provincial history of disaster exposure over the past two decades, we describe the relationship between disaster mortality and morbidity, disasters’ economic damages, government investment and regional economic activity, and infrastructure development. The Chinese government’s aggressive investment in post-disaster reconstruction is discussed, and the implications of this investment for post-disaster private sector economic activity are analyzed empirically. We further investigate the differential effects of natural disasters on economic activity in China’s diverse geographical regions.  相似文献   
42.
The methods of in-mine seam-sounding and transillumination (geoelectric tomography) for the detection of tectonic disturbances of coal seams were developed by the Department of Geophysics of the University of Miskolc in the 1970–80’s with the effective support of the former “Borsod” Coal Mines Ltd. The paper gives an overview about the theory of seam-sounding and a special geoelectric tomographic inversion, and introduces the in-mine geoelectric seam-sounding and transillumination measurement systems using vertical electrode dipoles. In the second part the paper, the results of an in-mine geoelectric measurement are presented, which was carried out in order to detect tectonic disturbances of the Miocene aged coal seams situated in Slovakia. As results of the geophysical investigation, the authors forecasted the tectonic features in the coal seam. The company confirmed the results by independent information about seam disturbances and tectonic features arising from the excavation of the investigated area.  相似文献   
43.
Although the úrkút manganese ore deposit in western placecountry-regionHungary has been exploited for at least 90 years, there are still numerous open questions concerning ore genetics as well as structure and geometry of the ore body. A large set of available archive data for the deposit have been reviewed and evaluated in order to solve some of the most crucial problems. For processing, besides diverse GIS approaches, univariate and multivariate statistical methods were used on the created unified database. The main aims of the mathematical treatment were giving a classification scheme for the wide spectrum of Mn-ores based on their chemical composition (Mn, Fe, Si, P) as well as evaluation of their spatial distribution. For the ore characterization and understanding the genetic processes, cluster and discriminant function analyses were used. Results of the multivariate treatment verified the existence of different ore types and provided an exact chemical definition for all of them. It alsoinferred that the main geochemical processes that took place in ore genesis were similar for all sample groups (ore types) with significantly different weights in each case. A 3D evaluation of the úrkút mine heading map system shows that the ore body covers the footwall surface as a stratiform sheet throughout the study area. Palaeo-relief studies suggest a significant difference between the footwall and hanging wall morphologies which clearly implies tectonic activity following ore deposition. The deposit was affected by an E-W compression stress field near the Aptian-Albian transition causing folding of the Mn deposit.  相似文献   
44.
GPS systems can be used as seismometers by sampling ground positions to detect travelling seismic waves. Data from dense geodetic networks near large earthquakes have been used to improve magnitude estimates, for tsunami warning, and to better understand the rupture processes. Here, we present 1 Hz GPS records of the March 11th, 2011, Mw = 9.0 Tohoku earthquake at unprecedented teleseismic distances. The spatial and temporal variations of the three‐dimensional GPS displacement vector field show various body waves, Love and Rayleigh surface waves along the direct path, and Love waves from the more than 31 000 km long major arc path. These results suggest that seismic wavefields can be mapped at teleseismic distances globally using space geodesy and could thus be used for source and structural studies. Data from numerous real‐time kinematic GPS networks could be combined to show the displacement field, giving unparalleled views of Earth's response to large earthquakes.  相似文献   
45.
The present investigation compared the capacity of greenhouse pot-cultivation systems under two salinity conditions (freshwater and saline water) with two mangrove species (Bruguiera gymnorrhiza and Kandelia candel) to remove nutrients from livestock wastewater. During the whole treatment period there were relatively stable leachate TOC concentrations for wastewater-treated pots. Leachate NH4(+)-N concentration of B. gymnorrhiza pots was generally lower than that of K. candel pots. Leachate PO4(3-)-P concentration of pots receiving wastewater under freshwater condition was higher than that under saline water condition. Soil inorganic N content was more than two times higher for the wastewater treatments than that for the controls under low salinity condition and slower rate of increase under saline water condition. Soil P nutrients of both total and extractable inorganic forms significantly increased for both systems due to the discharges of livestock wastewater under both salinity conditions. The rate of increase in P contents for plants receiving livestock wastewater was 1-4 times that of the controls, much more than that in N contents (0.04-1.30 times). N nutrient removal efficiencies were 84.3% (65.6% by soil and 18.7% by plant) and 95.5% (32.2% by soil and 63.4% by plant), respectively by Kandelia candel and B. gymnorrhiza pot-cultivation systems under freshwater condition. Under saline water condition, N nutrient removal efficiencies by K. candel and B. gymnorrhiza pot-cultivation systems were 92.7% (80.7% by soil and 12.0% by plant) and 98.0% (67.6% by soil and 30.3% by plant), respectively. P nutrient removal efficiencies by K. candel and B. gymnorrhiza systems under freshwater condition were 79.2% (76.6% by soil and 2.6% by plant) and 91.8% (88.2% by soil and 3.6% by plant), respectively. The corresponding values were 88.0% (84.2% by soil and 3.8% by plant) and 97.8% (95.9% by soil and 1.9% by plant) under saline water condition.  相似文献   
46.
A vegetation analysis reveals that the Lai Chi Wo mangrove swamp in Hong Kong has 10 mangrove species comprising 76.9% of the total number of mangrove species in Hong Kong. This swamp is a mixed community dominated byAegiceras corniculatum, Heritiera littoralis, Excoecaria agallocha, Kandelia candel, Bruguiera gymnorrhiza, with importance values of 37.88, 28.19, 14.33, 11.33 and 8.27 respectively. The community’s mangrove species diversity and evenness, as based on the Shannon-Wiener Function, were 1.44 and 62.01%, which were lower than those of the south su-tropical evergreen broad-leaf forest community but its ecological dominance (0.26) was higher. The correlation information field (CIF) method, a useful analytical method for complex forest community, was adopted in the present mangrove analysis. The species correlation information was:Aegiceras corniculatum (0.268)>Heritiera littoralis (0.250)>Kandelia candel (0.220)>Excoecaria agallocha (0.169)>Bruguiera gymnorrhiza (0.101). The correlation information of the mangrove community was 1.008. This work was financially supported by the Agriculture and Fisheries Department of The Hong Kong Government and The Hong Kong University of Science & Technology.  相似文献   
47.
Urbanization is a current and increasing threat to biodiversity. The effects of urbanization on the functional and taxonomic composition of macroinvertebrate assemblages were investigated in two seasons along a small urban stream. Species composition was determined by the rate of urbanization; however, response of species richness could not be evidenced. Relative abundance of the sensitive macroinvertebrate groups (EPT%) was negatively related to urbanization. Almost all feeding groups showed a sharp decline in the number of specimens along the increase of urbanization. The study supports the view that urbanization has a negative effect on the biological quality of a stream, yet, this obvious impact can be overridden by different measures such as modification in streambed morphology. The altered conditions and new circumstances in urban environments lead to the creation of novel ecosystems, inhabited by macroinvertebrate communities with species richness approaching that of low impacted sites. However, species composition of these communities could be basically different from that of the natural ones.  相似文献   
48.
Based on Helios measurements, seven quantities of normalized PDF (Probability Distribution Function) associated with magnetic field and its disturbances are utilized to characterize the intermittency in the fast solar wind using Castaing distributions and the idea of “Flatness”. The magnetic field fluctuations are found to be more intermittent at farther distances from the sun. The “Flatness” decreases with increasing time scales, with the corresponding PDF eventually approaching Gaussian distributions. Such a transition occurs at a relatively small time scale for the perpendicular component of perturbed field. The increase in “Flatness” with decreasing time scale is more apparent farther from the sun. By examining how the relative energy density of magnetic disturbances at various time scales changes with the mean field, our study supports the idea that the perturbed fields in the fast solar wind in the frequency range considered are consistent with cross-scale redistribution of wave energy favoring larger scales.  相似文献   
49.
INTRODUCTIONChrbondioxideandInehanearethetwomostabundantabosphericcarbonspedes.Methane'sconcenhati0nintheboposphereinonsesO.7-l.l%peryearraasmussenandKhaili,l98l,BlakeandRowand,l988,Scheeetal.,l989).Ihauseofmethne'sforpaCtontheearth'sclirnateandthechernistryoftheatInosphere,thebudgetofabosphericmethanehasmivedconsiderableattchti0n.Wetlandsareestirnataltobeoneofthelamptsoimofabosphericmethane,aocountingforab0ut4O%to5O%0ftheglobalInehanesoonannually(Cforneand0reInland,l988,WhitingandC…  相似文献   
50.
Previously, little attention has been paid to terrestrial radioisotopes (U, Th, 40K) occurring in manganese ores, despite the fact that the biogeochemical relationship between Mn and U is versatile. Occurrence of terrestrial radioisotopes in great amounts during mining on a long-term causes significant radiation exposure. It is important to inspect black shale-hosted manganese ores from this aspect, as black shales are typically potential U-rich formations. Despite the increased radon concentration in the mine, based on the detailed major elements, trace elements and gamma spectroscopy inspection of the rock types of deposit, the U, Th enrichment was undetectable. However, the U and Th content of about average terrestrial abundance of the great ore amount may be in the background of the increased radon concentration level. This Mn-carbonate ore deposit in spite of the low U content exhibit potential radon danger for miners, which can be eliminated with intensive air change only.  相似文献   
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