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101.
Landslides - A Correction to this paper has been published: https://doi.org/10.1007/s10346-021-01646-0. 相似文献
102.
Landslides - Assessment of the spatial probability of future landslide occurrences for disaster risk reduction is done through landslide susceptibility modelling. In this study, we investigated the... 相似文献
103.
Martha Tapas Ranjan Roy Priyom Jain Nirmala Khanna Kirti Mrinalni K. Kumar K. Vinod Rao P. V. N. 《Landslides》2021,18(6):2125-2141
Landslides - India ranks first in the world in terms of fatal landslides. Large vulnerable area (0.42 million km2), high population density and monsoon rainfall make India’s landslide... 相似文献
104.
现代地层学研究中一个关键的问题是陆相和浅海相地层的对比和整和,尽管层序地层学在两种地层中均有很大发展,可是很少有成功的两者对比研究,本文的目的就是用陆地有机相和海相地层水进水退来产生一种新的层序地层演化的整和模式。 相似文献
105.
Yanis Bouchenak-Khelladi Jean-Dominique Durand Antonios Magoulas Philippe Borsa 《Journal of Sea Research》2008,59(4):269-278
Atlantic–Mediterranean anchovies were genetically characterized at two polymorphic nuclear loci (intron 6 of two creatine-kinase genes) and compared to reference Engraulis albidus and E. encrasicolus samples from the northern Western Mediterranean to provide new insights into their geographic structure. Northeastern Atlantic anchovy, represented by one sample from the Canary archipelago and one sample from the Alboran Sea, were genetically distinct from Mediterranean E. encrasicolus (Weir and Cockerham's ^θ = 0.027–0.311), indicating geographic isolation from either side of the Almería–Oran oceanographic front. Generally smaller genetic differences were evident among anchovy populations from different sub-basins in the Mediterranean (^θ = − 0.019–0.116), the genetic differences between Black Sea and Ionian Sea/Aegean Sea anchovies being the strongest (^θ = 0.002–0.116). There was no evidence of the presence of E. albidus in our samples outside Camargue (northern shore of the Western Mediterranean). However, a sample from the southern Western Mediterranean appeared to be genetically intermediate between E. albidus and Mediterranean E. encrasicolus, indicating possible hybridization. Anchovy from the Benguela current system off southern Africa possessed allele frequencies characteristic of E. albidus at one locus and Northeastern Atlantic anchovy at the other locus, suggesting past introgression. 相似文献
106.
Aerosol samples were collected at two coastal suburban stations, Qingdao (China) in 1995-1996 and Liverpool (U.K.) in 1995, respectively. The samples were analyzed to determine the concentrations of trace metals (Cr, Zn, Cu, Co, Ni, Pb, V, and Cd) as well as A1, Fe and Mn. Data were examined to understand the difference of trace metals in aerosols between coastal zones downwind the developing area (near the Yellow Sea) and developed region (near the Irish Sea). The results show that most elements at Qingdao have levels 4-5 times higher than those at Liverpool, particularly for the crust-dominated elements (e.g. Al, Fe and Mn). Moreover, the aerosol composition at Qingdao is higher in spring than in summer, underlying the influence of westerlies and local emissions in combination, whereas seasonal change of aerosol composition is not significant at Liverpool. The enrichment factors for the crustal source elements (EFcrust) at Liverpool are much higher than those at Qingdao. The contributions from the pollutant source (Rp) for some trace metals like Cu, Pb, Zn and Cd are 〉90% at Qingdao and Liverpool, suggesting overwhelming anthropogenic contributions to these metals. The contributions from crustal source (Re) for trace metals tend to increase with higher aerosol levels and Al concentration at Qingdao, indicating a good correlation between the crust-dominated component and the air mass. At Liverpool, the Rc values for trace metals are positively correlated with Al concentrations instead of with aerosol mass, suggesting that Al in aerosols represents the crustal component even though the aerosols come from different sources. 相似文献
107.
Sea level rise threatens coastal communities throughout the United States, and South Florida is on the front line. The iconic and built-up city of Miami Beach, Florida, has a well-developed, high-value property market, and the municipality has been lauded for proactively taking action to adapt to anticipated sea level rise. Moving beyond hyperbole and piecemeal evidence, we compile a comprehensive inventory of adaptation and mitigation measures implemented by various municipal agencies. We employ these data sets to measure exposure and readiness for the entire city and make a preliminary effort to develop a city vulnerability index. Our findings reveal that exposure throughout the city is high and that readiness is concentrated near stormwater drainage systems, leading to high vulnerability along the coast. When we compare the spatial patterns of the vulnerability index and the residential property values, we find a mismatch. The most vulnerable regions are characterized by high income, transiency, and an apparent unresponsiveness to sea level rise. No doubt our findings illustrate a lag effect, but if sea level rise increases, the real estate market could reach a tipping point unless state and federal agencies also fund more comprehensive adaptation. 相似文献
108.
Dagasan Yasin Renard Philippe Straubhaar Julien Erten Oktay Topal Erkan 《Natural Resources Research》2019,28(1):153-171
Natural Resources Research - Geological contacts in lateritic metal deposits (footwall topographies) often delineate the orebody boundaries. Spatial variations seen in such contacts are frequently... 相似文献
109.
The purpose of this study is to estimate long-term SMC and find its relation with soil moisture (SM) of climate station in different depths and NDVI for the growing season. The study area is located in agricultural regions in the North of Mongolia. The Pearson’s correlation methodology was used in this study. We used MODIS and SPOT satellite data and 14 years data for precipitation, temperature and SMC of 38 climate stations. The estimated SMC from this methodology were compared with SM from climate data and NDVI. The estimated SMC was compared with SM of climate stations at a 10-cm depth (r2 = 0.58) and at a 50-cm depth (r2 = 0.38), respectively. From the analysis, it can be seen that the previous month’s SMC affects vegetation growth of the following month, especially from May to August. The methodology can be an advantageous indicator for taking further environmental analysis in the region. 相似文献
110.
Giant gaseous layers(termed “superdisks”) have been hypothesized in the past to account for the strip-like radio emission gap(or straight-edged central brightness depression) observed between twin radio lobes, in over a dozen relatively nearby powerful Fanaroff-Riley Class II radio galaxies. They could also provide a plausible alternative explanation for a range of observations. Although a number of explanations have been proposed for the origin of the superdisks, little is known about their material content. Some X-ray observations of superdisk candidates indicate the presence of hot gas, but a cool dusty medium also seems to be common. If they are entirely or partly composed of neutral gas, then it may be directly detectable and we report here a first attempt to detect/image any neutral hydrogen gas present in the superdisks that are inferred to be present in four nearby radio galaxies. We have not found a positive H I signal in any of the four sources, resulting in tight upper limits on the H I number density in the postulated superdisks,estimated directly from the central rms noise values of the final radio continuum subtracted image. The estimated ranges of the upper limit on neutral hydrogen number density and column density are 10^-4-10^-3 atoms per cm3 and 10^19-10^20 atoms per cm^2, respectively. No positive H I signal is detected even after combining all the four available H I images(with inverse variance weighting). This clearly rules out an H I dominated superdisk as a viable model to explain these structures, however, the possibility of a superdisk being composed of warm/hot gas still remains open. 相似文献