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61.
Human residency is the spatial effect source on ecosystem and thus it should be studied and assessed. Supporting residency effect research, this study developed and applied procedures and a model to combine census and parcel data for the assessment. The case study is in Pocatello, Idaho, where revealing land service associated with flood control and locating/evaluating resident effect are needed. Methods include (1) data mining, (2) land service valuation, (3) data screening, (4) integration of census and parcel data, (5) data screening, and (5) analysis and modeling with R programing language and ArcMap. Results are, for land service assessment, land value per area unit in residence areas (LAND) along the concrete channel (for flood control) was less than that along the Portneuf River. Spatial responses under LAND to a source effect (either the concrete channel or the river) are the same. The applied methods helped locate and assess a variety of residency effects spatio-temporally. Results informed the human preferences under LAND and the effect distribution to support decision-making. Technically, using the parcels as a baseline provided comprehensive results with a fine resolution for the effect study, particularly as combined with the census data. This study suggests using a data screening and validation procedure besides the mining approach to minimize outcome uncertainty.  相似文献   
62.
The exploitation of natural resources within areas that are valued for their environmental qualities raises competing emotions. This paper considers a proposal to undertake petroleum exploration in an area of recognised environmental value, namely, the Coongie Lakes of far north-east South Australia. In development cases such as this, the level of inquiry needs to address environmental, social, cultural and economic issues from a range of interest groups; therefore, the process of assessment is a crucial factor in minimising conflict and meeting the wishes of the stakeholders. In the example of Coongie Lakes, the chosen method failed. This paper discusses the perspectives of the major stakeholders, the process of assessment undertaken, and the criticisms directed at this process. The apparent inadequacies of the assessment process undertaken are then highlighted, and an alternative assessment procedure suggested.  相似文献   
63.
The New Zealand region contains untapped natural mineral, oil, and gas resources while also supporting globally unique and diverse faunal communities that need to be managed sustainably. In this paper key information from the international literature is reviewed that can underpin an Environmental Mining Management System which includes elements of Environmental Risk Assessment, Environmental Impact Assessment and Environmental Management Planning. This paper focuses on four developing areas of seafloor mining activities presently being undertaken or planned in the New Zealand region: hydrocarbons (oil and gas), minerals, ironsands and phosphorite nodules. A number of issues with the implementation of environmental management systems are identified including the difficulty of assessing new marine activities or technologies and the need for standardised reporting metrics. Finally, the development of ecosystem-based management and marine spatial planning is discussed which will be required to enhance environmental mining management frameworks in New Zealand.  相似文献   
64.
We conducted the first quantitative assessment of coral breakage along a gradient of diving activities in Hong Kong, the most densely populated city in southern China. A survey of six 1 × 25 m transects at seven sites revealed a total of 81 broken corals, among which 44% were branching, 44% plate-like and 12% massive. There were 3–19 broken colonies per site. At most study sites, the percentage of broken corals exceeded the recommended no-action threshold of 4%, suggesting that management intervention is justified. There was a significant positive correlation between the number of broken coral colonies and the number of divers visiting the site. The branching Acropora and the plate-like Montipora suffered from much higher frequency of damage than their relative abundance, raising the concern that the cumulative impact of such differential susceptibility to breakage may affect coral community composition.  相似文献   
65.
根据2001年至2010年间"中国知网"针对《四川地震》进行的统计,简要分析了影响《四川地震》期刊质量的几个指标。结果表明,机构用户数量在2001年至2010年间一直在增加,但发行范围是稳定的,这说明地震专业性期刊的阅读者是特定机构的研究人员,而且在同一时期的来稿数量保持稳定也说明了期刊的稿源也局限在特定研究机构内;同时根据"中国知网"的统计反馈意见知道:影响因子的主要贡献因素是地震台站监测仪器革新技术和有关地震台站技术管理方面的文章;地震预测预报研究中的前兆观测项目分析这一类资料性文章是《四川地震》影响因子的次要贡献因素;其他类型文章的贡献还要小些。可以看出,地震台站观测技术创新型文章是《四川地震》期刊提高质量的关键因素。  相似文献   
66.
Southeast Asian countries suffer from severe coastal hazards each year. A large number of these countries are incurring consequential costs that impact their national economies. It is crucial, therefore, to analyze the impact of such hazards on their economic development and provide a solid basis for future development strategies. The purpose of this paper is to assess the relationship between the economic development and the losses from coastal disasters, and to identify both the impact of hazards on the development, as well as the function of such development on the resilience to hazards. The data envelopment analysis (DEA) method is employed to build the assessment models. Data from 1995 to 2005 from eight Southeast countries are analyzed using the DEA models. A set of “resilience index” of these countries are concluded from the results. It is found that the economic development does not contribute to the strengthening of national resilience to coastal hazards. Inappropriate development could even impair the resilience. Additionally, the resilience to coastal hazards is impacted by various factors such as the allocation of resources and external assistance. From the analysis, a clear image is gained of the interaction between economic development and coastal hazards, which provides a basis for future development strategies.
Yi-Ming WeiEmail: Email:
  相似文献   
67.
The 1945 Tsunami generated due to Makran Earthquake in the Arabian Sea was the most devastating tsunami in the history of the Arabian Sea and caused severe damage to property and loss of life. It occurred on 28th November 1945, 21:56 UTC (03:26 IST) with a magnitude of 8.0 (M w), originating off the Makran Coast of Pakistan in the Arabian Sea. It has impacted as far as Mumbai in India and was noticed up to Karvar Coast, Karnataka. More than 4,000 people were killed as a result of the earthquake and the tsunami. In this paper an attempt is made for a numerical simulation of the tsunami generation from the source, its propagation into the Arabian Sea and its effect on the western coast of India through the use of a numerical model, referred to as Tunami-N2. The present simulation is carried out for a duration of 300 min. It is observed from the results that the simulated arrival time of tsunami waves at the western coast of India is in good agreement with the available data sources. The paper also presents run-up elevation maps prepared using Shuttle Radar Topographic Mission (SRTM) data, showing the possible area of inundation due to various wave heights along different parts of the Gujarat Coast. Thus, these results will be useful in planning the protection measures against inundation due to tsunami and in the implementation of a warning system.  相似文献   
68.
K. Miljkovi?  N.J. Mason 《Icarus》2011,214(2):739-747
Using the light gas gun at the Open University’s Hypervelocity Impact facility, a series of impact experiments exploring impacts into water ice and gypsum have been performed. Fragmentation of solid ejecta was recorded using two different methods, analysed and compared with the total ejecta. Preliminary results show that the size distribution of the ejecta fragments from water ice is very similar to those from gypsum. These results also represent a step towards a better understanding of ejecta fragmentation in geological materials, including icy surfaces in the Solar System.  相似文献   
69.
We report laboratory studies on the 0.8 MeV proton irradiation of ices composed of sulfuric acid (H2SO4), sulfuric acid monohydrate (H2SO4·H2O), and sulfuric acid tetrahydrate (H2SO4·4H2O) between 10 and 180 K. Using infrared spectroscopy, we identify the main radiation products as H2O, SO2, (S2O3)x, H3O+, , and . At high radiation doses, we find that H2SO4 molecules are destroyed completely and that H2SO4·H2O is formed on subsequent warming. This hydrate is significantly more stable to radiolytic destruction than pure H2SO4, falling to an equilibrium relative abundance of 50% of its original value on prolonged irradiation. Unlike either pure H2SO4 or H2SO4·H2O, the loss of H2SO4·4H2O exhibits a strong temperature dependence, as the tetrahydrate is essentially unchanged at the highest irradiation temperatures and completely destroyed at the lowest ones, which we speculate is due to a combination of radiolytic destruction and amorphization. Furthermore, at the lower temperatures it is clear that irradiation causes the tetrahydrate spectrum to transition to one that closely resembles the monohydrate spectrum. Extrapolating our results to Europa’s surface, we speculate that the variations in SO2 concentrations observed in the chaotic terrains are a result of radiation processing of lower hydration states of sulfuric acid and that the monohydrate will remain stable on the surface over geological times, while the tetrahydrate will remain stable in the warmer regions but be destroyed in the colder regions, unless it can be reformed by other processes, such as thermal reactions induced by diurnal cycling.  相似文献   
70.
Impact craters on planetary bodies transition with increasing size from simple, to complex, to peak-ring basins and finally to multi-ring basins. Important to understanding the relationship between complex craters with central peaks and multi-ring basins is the analysis of protobasins (exhibiting a rim crest and interior ring plus a central peak) and peak-ring basins (exhibiting a rim crest and an interior ring). New data have permitted improved portrayal and classification of these transitional features on the Moon. We used new 128 pixel/degree gridded topographic data from the Lunar Orbiter Laser Altimeter (LOLA) instrument onboard the Lunar Reconnaissance Orbiter, combined with image mosaics, to conduct a survey of craters >50 km in diameter on the Moon and to update the existing catalogs of lunar peak-ring basins and protobasins. Our updated catalog includes 17 peak-ring basins (rim-crest diameters range from 207 km to 582 km, geometric mean = 343 km) and 3 protobasins (137-170 km, geometric mean = 157 km). Several basins inferred to be multi-ring basins in prior studies (Apollo, Moscoviense, Grimaldi, Freundlich-Sharonov, Coulomb-Sarton, and Korolev) are now classified as peak-ring basins due to their similarities with lunar peak-ring basin morphologies and absence of definitive topographic ring structures greater than two in number. We also include in our catalog 23 craters exhibiting small ring-like clusters of peaks (50-205 km, geometric mean = 81 km); one (Humboldt) exhibits a rim-crest diameter and an interior morphology that may be uniquely transitional to the process of forming peak rings. A power-law fit to ring diameters (Dring) and rim-crest diameters (Dr) of peak-ring basins on the Moon [Dring = 0.14 ± 0.10(Dr)1.21±0.13] reveals a trend that is very similar to a power-law fit to peak-ring basin diameters on Mercury [Dring = 0.25 ± 0.14(Drim)1.13±0.10] [Baker, D.M.H. et al. [2011]. Planet. Space Sci., in press]. Plots of ring/rim-crest ratios versus rim-crest diameters for peak-ring basins and protobasins on the Moon also reveal a continuous, nonlinear trend that is similar to trends observed for Mercury and Venus and suggest that protobasins and peak-ring basins are parts of a continuum of basin morphologies. The surface density of peak-ring basins on the Moon (4.5 × 10−7 per km2) is a factor of two less than Mercury (9.9 × 10−7 per km2), which may be a function of their widely different mean impact velocities (19.4 km/s and 42.5 km/s, respectively) and differences in peak-ring basin onset diameters. New calculations of the onset diameter for peak-ring basins on the Moon and the terrestrial planets re-affirm previous analyses that the Moon has the largest onset diameter for peak-ring basins in the inner Solar System. Comparisons of the predictions of models for the formation of peak-ring basins with the characteristics of the new basin catalog for the Moon suggest that formation and modification of an interior melt cavity and nonlinear scaling of impact melt volume with crater diameter provide important controls on the development of peak rings. In particular, a power-law model of growth of an interior melt cavity with increasing crater diameter is consistent with power-law fits to the peak-ring basin data for the Moon and Mercury. We suggest that the relationship between the depth of melting and depth of the transient cavity offers a plausible control on the onset diameter and subsequent development of peak-ring basins and also multi-ring basins, which is consistent with both planetary gravitational acceleration and mean impact velocity being important in determining the onset of basin morphological forms on the terrestrial planets.  相似文献   
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