Geomorphological models as a tool for environmental studies

Relief is understood as a fundamental component of the environmental system. The structure of geomorphodynamic processes and of the relief sphere as the main energy transformation surface is a determining factor for environmental conditions of both sites and areas. Modelling is the instrument of the applied and systems analytic approach to geomorphology. Geomorphological tools are appropriate means of determining, structuring, assessing and predicting the geoecological potential of the environment. This is demonstrated by quantitative and multivariate models to describe spatial patterns of the environment (fluvial network analysis) and to evaluate and present environmentally relevant geomorphological disposition (slope stability analysis).     

Citizen monitoring during hazards: validation of Fukushima radiation measurements

Citizen-led movements producing scientific hazard data during disasters are increasingly common. After the Japanese earthquake-triggered tsunami in 2011, and the resulting radioactive releases at the damaged Fukushima Daiichi nuclear power plants, citizens monitored on-ground levels of radiation with innovative mobile devices built from off-the-shelf components. To date, the citizen-led Safecast project has recorded 50 million radiation measurements worldwide, with the majority of these measurements from Japan. The analysis of data which are multi-dimensional, not vetted, and provided from multiple devices presents big data challenges due to their volume, velocity, variety, and veracity. While the Safecast project produced massive open-source radiation measurements at specific coordinates and times, the reliability and validity of the overall data have not yet been assessed. The nuclear disaster at the Fukushima Daiichi nuclear-power plant provides a case for assessing the Safecast data with official aerial remote sensing radiation data jointly collected by the governments of the United States and Japan. This study spatially analyzes and statistically compares the citizen-volunteered and government-generated radiation data. An assessment of the Safecast dataset requires several preprocessing steps. First, it was necessary to convert the data from the Safecast ionized radiation sensors since they were collected using different units of measure than the government data. Secondly, the normally occurring radiation and decay rates of cesium from deposition surveys were used to properly compare measurements in space and time. Finally, the GPS located points were selected within overlapping extents at multiple spatial resolutions. Quantitative measures were used to assess the similarity and differences in the observed measurements. Radiation measurements from the same geographic extents show similar spatial variations and statistically significant correlations. The results suggest that? actionable scientific data for disasters and emergencies can be inferred from non-traditional and not vetted data generated through citizen science projects. This project provides a methodology for comparing datasets of radiological measurements over time and space. Integrating data for assessment from different Earth sensing systems is paramount for societal and environmental problems.     

Coral microatoll as geodetic tool in North Andaman and Little Andaman,India

Coral microatolls were examined from North Andaman and Little Andaman to understand the relative sea level change due to vertical tectonic deformation above the subduction interface. The highest level of survival of coral microatoll before the 26 December, 2004 earthquake at eastern coast of North Andaman has been determined by Global Ocean Tide Model. The present position of recently dead flat top microatoll with preserved internal structure at the eastern coast of North Andaman mainland indicates 31.21 cm uplift due to the 26 December, 2004 earthquake. Comparatively old cup shaped microatoll at the eastern fringe of North Andaman group of islands and highly bioeroded fossil microatolls at the intertidal zone of Little Andaman bear the signature of permanent vertical deformation in the past.     

Possible refugia for reefs in times of environmental stress

This paper investigates the refuge potential of (1) upwelling areas, (2) coral areas at medium depth, and (3) offshore bank and island reefs in a scenario of increased global warming, and thus increased sea surface temperature (SST) and increased solar UV radiation. (1) Observations on coral health and water temperature in the subtropical Atlantic (Eleuthera and Cat Island, Bahamas) and Indian Ocean (Sodwana Bay, South Africa) suggest a link between cool water delivered by upwelling and coral health. After the 1998 bleaching event, caused by strong SST anomalies, coral health and recovery from the previous year's bleaching was significantly better on the narrow southern Cat Island shelf (70% of corals healthy) where the presence of cold water was observed, which was attributed to small-scale upwelling, than on the wide northern Eleuthera shelf (44% of corals healthy), where downwelling of hot bank waters was believed to have damaged corals. In South Africa, regular, short-term upwelling events in five summers reduced SST to well below bleaching level. (2) In the northern Red Sea (Safaga Bay) and in South Africa (Sodwana Bay), wide areas with either coral frameworks or non-framework communities exist. Calculations show that if the top 10 m (20 m) of the ocean became inhospitable to corals, still 50.4% (17.5%) of the coral area would remain intact in the Red Sea and 99% (40%) in South Africa. (3) Offshore bank and island reefs investigated in the Turks, Caicos, and Mouchoir Banks and Grand and Little Cayman showed high rates of mortality and coral diseases. The most remote sites (Mouchoir Bank) were not the healthiest. Refuge areas appear to exist in (1) and (2), but in (3) only if vigorous water-circulation is encountered.     

Multicollector ICPMS as tool for isotopic fingerprinting in environmental, biomedical and geochemical studies

Stable isotopes, such as C, N, O and S, are successfully used as classical environmental tracers. During the last few years, heavy stable isotopes are getting more and more attention as tracers and proxies in biogeochemical and environmental studies. Multicollector Inductively Coupled Plasma Mass Spectrometry （MC-ICPMS） has enabled scientists to obtain high precise isotopic analyses of heavy elements such as Cl, Ca, Fe, Cu, Zn, Hg and Pb. These isotopic systems can be used as important tracers in studying metal contaminants, biomedical processes and pollution of aquatic environments. MC-ICPMS is a powerful technique for the isotopic analysis of most elements, with the exception of light elements such as H, C, N and O and noble gases. The advantage of the ICP source is that it can ionize all elements with very high sensitivity. Various inlet systems can be used to introduce samples into the mass spectrometer, for instance gas chromatography （GC）, liquid chromatography （LC）, laser ablation, or conventional liquid nebulization. The aerosol is transported by an Ar and/or He gas flow into the ICP source where it is effectively ionized and introduced into the mass analyzer through a differential pumping system. The variable multicollector detector array allows the user to adjust the detector positions along the focal plane of the mass spectrometer so that all isotopes of interest can be measured simultaneously. Molecular interferences as carbides, nitrides, oxides, argides or doubly-charged species can show up in the mass spectrum and interfere with the elemental isotope peaks. High mass resolution is needed to effectively discriminate against these interferences. The ion optics of the Finnigan NEPTUNE is specially designed to meet this requirement and expand the power of isotope ratio measurements even to elements where previously isobaric interferences were the limit.     

地质灾害监测技术现状与发展趋势

文章对地质灾害监测方法、监测仪器进行了系统归类。详细介绍了崩滑体变形监测、物理场与化学场监测、地下水监测和滑坡等诱发因素监测方法、特点。对地质灾害监测方法的应用现状进行了总结；文章还介绍了BOTDR新技术的起源与发展、基本原理和应用于地质灾害监测的几个关键问题；对地质灾害监测方法的发展趋势进行了预测；最后文章提出了进行地质灾害监测技术优化集成的基础和优化原则。     

基于WebGIS的环境地质灾害网络数据库系统

目前,大量环境和地质灾害数据库的建设主要处于单机、封闭的系统形式,导致数据信息的管理、更新和使用落后于社会对信息的需求,花费巨资建立的数据库资源无法被需要者利用,难于实现信息共享,从而变为数量众多“信息孤岛”。改变这种局面的主要技术途径就是建立一个通用、高效、开放的平台来管理、发布和共享这些空间数据。本文结合信息技术与GIS的最新发展趋势,介绍了WebGIS,一种GIS与网络技术相融合产物的主要技术特征,并结合实例,简要论述了系统的建设要求、体系结构、技术构成等。利用ArcIMS以及数据库、ASP等技术建立起“环境与地质灾害网络数据库系统”,实现了地质环境和地质灾害空间信息的集中管理、远程浏览查询、信息共享等功能。     

火山监测研究进展及其对中国火山灾害监测预警工作的启示

中国及邻区分布着众多的全新世陆相活火山,并留下了大量的喷发历史记录。对这些活火山开展监测和研究工作是预测火山喷发和火山灾害减灾防灾工作的重要途径。高度剥蚀的晚中生代火山区的大量地质填图,以及在活火山区的地球物理、地球化学等近实时的探测工作,极大地深化了我国东部中生代—新生代陆相火山岩的成分特征、岩浆演化规律及喷发方式等方面的认识,是开展火山监测的理想研究对象。近年来,火山灾害日益引起关注,全球火山监测研究进展迅速。本文系统梳理了目前国内外主要的火山监测方法及取得的重要进展,并分析了未来火山灾害减灾防灾工作的发展趋势及我国火山监测工作的发展方向,旨在通过介绍国际火山监测工作,为我国将来开展火山监测、预测与火山灾害相关的减灾防灾等方面的研究和国际合作提供借鉴。     

Gravity data as a tool for landfill study

This paper shows the potential of gravity data to map a buried landfill bottom topography. To this end, a gravity inversion method is presented for estimating the landfill’s bottom depths at discrete points assuming a decrease of the density contrast with depth according to a hyperbolic law. The method’s efficiency was tested using synthetic data from simulated waste landfills, producing estimated bottom topographies very close to the true ones. The method’s potentiality has been further evaluated in applying it to the gravity data from the abandoned Thomas Farm Landfill site, Indiana, USA, whose bottom topography is known. The estimated topography showed close agreement with the known Thomas Farm Landfill’s bottom topography.     

Urbanization process and induced environmental geological hazards in China

Urbanization is a common development trend of countries all over the world, which is a mark of civilization and progress of human beings. The number of urbanization-induced environmental geological hazards has grown steadily in recent years and is receiving increased attention throughout the world. The purpose of this paper is to generalize China’s urbanization process and induced environmental geological hazards. Driving forces and characteristics of urbanization are briefly introduced in this study; specifically, the distribution of urban agglomerations is principally related to water resources, transportation and energy. Common geological hazards and particular ones in mountain city, mining city and coastal city are also summarized. The type and severity of hazards are different due to the differences of natural conditions and various urban functions. Main environmental geological hazards in cities are land subsidence, landslide and seawater intrusion, etc. Accordingly, reasons for these urbanization-induced geological hazards in different type of cities are analyzed and discussed. The research results may provide a clear perspective for urban geological hazard prevention, and suggestions for urban geological hazard control are pointed out.     

Preservation potential of seasonal laminated deposits as a useful tool for environmental analysis in mesotrophic Lake Kizaki,central Japan

In this paper discusses the aquatic environment at Lake Kizaki, central Japan, during the last ca. 60 years and describes the importance of laminated sediments in environmental analyses. The flux of total algal carbon increased between 1965 and 1996 while the BSi flux, which can be used in diatom production, showed a larger increase between 1960 and 1998 than typically occurs on average. The flux of dinosterol, an indicator of dinoflagellate production, also increased from 1966 to 1998, and the sedimentary dinoflagellate record correlated with observations of freshwater red tides caused by dinoflagellate blooms. Parallel laminated sediment was determined to have appeared between 1960 and 1995, corresponding to a period of high total algal carbon levels and BSi fluxes. For lamina formation and its preservation process, the thickness of the oxygen-poor layer depended on excessive total algal production during stagnant periods and appeared to be important because nutrients were diffused and accumulated in the oxygen-poor layer from bottom sediments. This could result in diatom blooms at the next overturn period. The development of the thick oxygen-poor layer appeared to be triggered primarily by the presence of excessive nutrients generated by human activities. In general, the occurrence of laminated sediments can provide a useful tool for understanding the eutrophic state in Lake Kizaki.     

Photogrammetry as a tool for detecting recent crustal movements

Progress in model building and in advanced exposure and evaluation methods is leading photogrammetry up into the field of precise point determination, up to now solved by classical geodetic triangulation and/or trilateration. In combination with the statistical test theory, photogrammetry can be used as a tool to detect recent crustal movements or deformations of man-made constructions, such as in coal mining or oil and gas exploitation.

For these reasons, this paper deals with model building for modern aerial triangulation with respect to hypothesis tests to detect point displacements greater than the measurement noise. An example from brown-coal mining demonstrates accuracies and the application of some statistical tests shows the efficiency of advanced aerial photogrammetry.     

Tracing environmental narratives: a web-based tool for the analysis and visualization of georeferenced narratives

A growing number of studies have used standalone GPS or smartphones to track where people move and the environment to which they expose. In the same time, questionnaire, survey, and travel diaries have been used to capture people’s perception, emotions, and interactions with the nearby environment. The growing volume of qualitative data together with locational information calls for new ways to conveniently, intuitively, and visually convey georeferenced narratives. In this study, we developed a web-based tool that automatically processes GPS trajectories and narratives, displays information regarding travel routes and georeferenced environmental perception. Our georeferenced word-cloud approach provides an innovative way to visualize qualitative information. The developed platform can be widely used in community engagement and participatory planning processes to empower the local communities.     

Radon as a geochemical exploration tool

Radon (Rn-222) is a unique element in the radioactive decay chain of U that has properties quite different from the other isotopes. Because Rn is radioactive, it can be detected at extremely low concentrations and this provides the basis for a very sensitive geochemical method. Radon has proven useful in exploring for not only U but for other associated elements. It has also been used successfully in exploring for geothermal sources, in earthquake prediction and in many other applications. With wider use of Rn as a geochemical tool in recent times has come a better understanding of the factors influencing its release, movement and detection. Studies of Rn emanation from a wide variety of U- and Ra-containing minerals have shown the effects of water content and other chemical and physical factors on the emanation rates. Published results from field research on Rn movement and experience with Rn as an exploration tool for uranium exploration have resulted in new data about the movement of Rn and its precursors in typical field situations. A number of new techniques for making integrated Rn measurements have been developed, and some appear to have some distinct advantages over the older grab sampling methods. This paper will discuss some of the more recent developments of Rn as a geochemical exploration tool and present new data on the numerous applications now utilizing Rn.     

Rip currents as a geological tool

This paper considers the nature and sedimentary significance of rip currents. Rip currents are the main factor responsible for the transport of coarse sediments from the littoral zone to greater depths. Such sediments, deposited outside the zone of wave deformation, may be identified as storm rip current increments within sediments deposited during fair weather. Composite beds deposited during a given wave cycle by storm rip currents are closely similar to ‘turbidites’ and many so called ‘fluxo-turbidites’ described from flysch deposits. Using data gathered in studies conducted on the modern Baltic coast, supplemented by experimental work and theoretical considerations, a sedimentary model is proposed. The model may be used to interpret possible rip current deposits among shallow water ‘turbidites’, and both modern storm sediments and ancient ‘tempestites’.