Use of stable water isotopes to assess sources and influences of slope groundwater on slope failure     

Tsung‐Ren Peng  Chung‐Ho Wang  Shih‐Meng Hsu  Nai‐Chin Chen  Tai‐Wei Su  Jiin‐Fa Lee 《水文研究》2012,26(3):345-355

This study employs stable oxygen and hydrogen isotopes as natural tracers to assess the headwater of a landslide next to a drainage divide and the importance of the slope's headwater in the study area. The study is undertaken near Wu‐She Township in the mountains of central Taiwan. Because a reservoir is located on the other side of the divide, this study evaluates the relationship between the reservoir water and headwater of the landslide as well. Over a 1‐year period, water samples from September 2008 to September 2009, including local precipitation (LP), Wu‐She Reservoir's water (WSRW), slope groundwater (SGW), upper‐reach stream water (USTW), and down‐reach stream water (DSTW), were analysed for deuterium (δD) and oxygen (δ¹⁸O) stable isotopes. Results indicate that WSRW is the predominant component in SGW: approximately 70% of SGW originates from WSRW and 30% from LP based on a two end‐member mass‐balance mixing model for δ¹⁸O. The similar two end‐member mixing model is also employed to assess the contributions of USTW and SGW to DSTW. Model results indicate that SGW is the major source of DSTW with a contribution of about 67%. Accordingly, about 47% of DSTW sources from the WSRW. In short, owing to reservoir leakage, WSRW contributes the greater part of both SGW and DSTW. Plentiful WSRW in SGW threatens the stability of the slope in the divide area. To avoid subsequent continuous slope failure, necessary mitigation steps are required. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

The cost of social vulnerability: an integrative conceptual framework and model for assessing financial risks in natural disaster management     

Lee  Sungyoon  Dodge  Jennifer  Chen  Gang 《Natural Hazards》2022,114(1):691-712

Natural Hazards - Groups that are unable to prepare for disasters, or to recover from damage on their own, have a high dependency on government services, which inevitably leads to more government...  相似文献   

Multi-proxy climate and environmental records from a Holocene eutrophic mire,southern taiga subzone,West Siberia     

Irina V. Kurina  Elena E. Veretennikova  Anna A. Il’ina  Marina L. Egorova  Lyudmila V. Salisch  Vladimir N. Dolgin  Albert V. Udaloi  Evgeniya A. Golovatskaya  Egor A. Dyukarev  Sergei V. Smirnov 《Boreas: An International Journal of Quaternary Research》2023,52(2):223-239

Palaeoenvironmental reconstructions from peat are strongly focused on ombrotrophic mires, but this study demonstrates that eutrophic mires can also be used. A multi-proxy approach was applied to a eutrophic mire on a floodplain terrace in the southern taiga of West Siberia. The results of the reconstruction were considered in the wide geographic context of the surrounding regions, including Siberia and Central Asia. Different palaeoecological proxies (analysis of plant macrofossils, testate amoebae, oribatid mites, molluscs, peat humification, ash content and spectral characteristics of humic acids) were used in this study. The results of different proxies showed a high level of consistency among themselves, which allowed for a robust interpretation of Holocene mire development. Throughout the ~7800 years history of the mire, there was a high level of surface wetness. The presence of mineral matter in the peat between 7800 and 5100 cal. a BP indicates regular flooding caused by the intensive fluvial activity, apparently resulting from increased precipitation. This was followed by a trend towards a gradual decrease in surface wetness from conditions of high surface moisture (stagnant water) between 5100 and 3000 cal. a BP to present day conditions of moderate surface moisture with a water table slightly below the mire surface. This pattern is consistent with the well-documented long-term trend from palaeoecological records throughout the taiga and arctic zones in West Siberia and central arid Asia. Our data further support the idea that the westerlies were the dominant driver of climate for the southern taiga of West Siberia during the Middle to Late Holocene.  相似文献   

Methylene blue transport in a sand-illite mixture and its implications for contaminant transport     

Lee  Seokjae  Yang  Subin  Lee  Dongjoon  Choi  Hangseok  Won  Jongmuk 《Hydrogeology Journal》2023,31(5):1245-1257

Understanding contaminant transport in clay-containing soils is critical for accurate prediction of the travel distances of contaminants and for the design and implementation of corresponding remediation plans. This study examined the breakthrough behavior of methylene blue (MB) through sand-illite mixtures using laboratory soil-column experiments at five inlet concentrations, three flow rates, and five illite contents. Kinetic and equilibrium adsorption tests were performed to evaluate the maximum adsorption capacities of the sand and illite used in the soil-column experiments. In addition, the bed efficiency, MB saturation, and adsorption rate were calculated to quantitatively describe the observed breakthrough curves. The observed breakthrough curves, bed efficiencies, MB saturations, and adsorption rates in this study demonstrated the presence of a threshold illite content of ~10% for the adsorption efficiency of contaminants. This implies the need to evaluate the threshold clay content for accurate predictions of contaminant transport through gap-graded clay-containing soils.

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The differentiated impact of emissions trading system based on company size     

Yoonmo Koo  Yoonha Lee  Yong-gun Kim 《Climate Policy》2019,19(7):923-936

Most countries implementing an emissions trading system (ETS), such as EU member states, California in the US, or South Korea, are generally targeting large sized companies, which consume energy above a specific threshold. However, previous studies using computable general equilibrium (CGE) models have analyzed climate policies without considering company size. This may have led to inaccurate results because the impacts of climate policy would differ depending on the coverage of regulated companies. Accordingly, this study examines the environmental and economic impacts of greenhouse gas emission reduction policies, assuming policy results vary by firm size, as covered by the Korean emission trading system. To this end, a CGE model with a separate social accounting matrix based on company size is used to compare three scenarios that reflect different types of carbon pricing methods. The results show that greenhouse gases will be reduced to a lower extent and utility will decrease more if mitigation policies are only imposed to large companies.

Key policy insights

• Carbon pricing policies should consider the different impacts on companies of different sizes and industry sectors.

• Without considering the different sizes of companies covered by an ETS, the expected carbon price and its economic impact will be underestimated.

• Small and medium-sized companies will face more negative impacts than large companies in some industry sectors under an ETS, even if the mitigation burden is only faced by large companies.

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Behavior of air particles associated with atmospheric recirculation over complex coastal area     

Soon-Hwan Lee  Geon-Young Park  Lim-Seok Chang  Chang-Keun Song 《Asia-Pacific Journal of Atmospheric Sciences》2015,51(4):311-322

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Effect of phenol on embryo development and expression of metallothionein in the sea urchin Hemicentrotus pulcherrimus     

Un-Ki Hwang  Ju-Wook Lee  Hyang-Mi Ryu  Ju-Chan Kang  Han Seung Kang 《Ocean Science Journal》2015,50(4):701-708

In this study, we identified and cloned the sea urchin Hemicentrotus pulcherrimus MT (Hp-MT) mRNA. We examined the gameto- and embryo-toxic effects and the expression of Hp-MT mRNA at various concentrations of phenol in H. pulcherrimus. We found that the normal embryogenesis rate was significantly inhibited when H. pulcherrimus was exposed to phenol (EC₅₀ = 1565.86 ppb, 95% Cl = 1183.47-2037.84 ppb). The no observed effective concentration (NOEC) and the lowest observed effective concentration (LOEC) of the normal embryogenesis rate were < 10 ppb and 100 ppb, respectively. Hp-MT cDNA is 651 bp in length and encodes a protein of 64 amino acids. We found that the expression of Hp-MT mRNA was significantly increased with phenol treatment in a concentrationdependent manner. These results suggest that phenol at greater than 100 ppb has a toxic effect during the early embryonic stages of H. pulcherrimus, and MT mRNA may be used as a biomarker for risk assessment of phenol contamination.  相似文献   

Under-ice measurements of suspended particulate matters using ADCP and LISST-Holo     

Ha  Ho Kyung  Kim  Yong Hoon  Lee  Hyun Jung  Hwang  Byongjun  Joo  Hyoung Min 《Ocean Science Journal》2015,50(1):97-108

Ocean Science Journal - Using a mooring package comprising an acoustic Doppler current profiler (ADCP) and holographic imaging system, a 1-day ice camp study was performed under the Arctic sea ice...  相似文献   

3-D Geovisualization of satellite images on smart devices by the integration of spatial DBMS,RESTful API and WebGL     

Hyong-Woo Kim  Dae-Sun Kim  Yang-Won Lee 《国际地球制图》2015,30(4):422-440

Recent technological advancements in web-based geographic information systems have enabled access to satellite images on smart devices. The Representational State Transfer (REST) architecture overcomes difficulties that are associated with conventional data communications on the web, and the Web Graphics Library (WebGL) can be used as an alternative to web-based three-dimensional geographic visualization (3-D geovisualization) due to its efficient image processing capabilities. This paper describes a 3-D geovisualization system that was developed for satellite images on smart devices by integrating a spatial database management system (DBMS), a RESTful application programming interface (API), and WebGL. Spatiotemporal objects were constructed for time-series satellite images within a DBMS and a RESTful API was built for spatiotemporal queries to the time-series database so that the requested satellite data could be represented in 3-D on smart devices using WebGL. Satellite images that are represented in WebGL give a more realistic 3-D experience when they are combined with terrain data and provide for intuitive observations of the relationships between pixel values and associated geospatial conditions. This paper shows that a creative combination of existing technologies can be used to enhance and display satellite images on smart devices for 3-D geovisualization.  相似文献   

Advanced methods for correcting measured precipitation and results of their application in the polar regions of Russia and North America     

E. G. Bogdanova  B. M. Il’in  S. Yu. Gavrilova 《Russian Meteorology and Hydrology》2007,32(4):229-244

The WMO recommendations on solid precipitation correction, based on generalized results of precipitation gauge intercomparisons performed in 1985–1996, do not take into account systematic errors in precipitation measurements such as wind-induced at high winds and false precipitation blown by wind into the precipitation gauge during strong blizzards at low temperatures, typical of high latitudes. To eliminate these biases in solid precipitation measurements in the Arctic latitudes, special procedures are proposed for three different national methods of precipitation measurement in Russia, the United States (Alaska), and Canada. Differences in the correction methods in these countries are caused by differences in the design of instruments, observation technique, climate, and content of data archives for calculating the measurement errors. Results of application of the proposed procedures for precipitation correction in the Arctic regions of the above-mentioned countries are discussed. The results are compared against the maps of corrected precipitation in the world water budget and snow, ice resources atlases and in the Handbook for Climate of the USSR.  相似文献