THE CAUSES OF WATERLEVEL CHANGES OF THE ARAL SEA IN THE HOLOCENE

A specialist in loess geomorphology and arid-zone hydrology distinguishes three categories of factors accounting for waterlevel changes in the Aral Sea. She judges the most significant to be changes in inflow resulting from changes in the course of the Amudarya, the more important of the two tributary streams. The Amudarya at various times emptied into the Sarykamysh depression, southwest of the Aral Sea, giving rise to a flow of water through the now dry Uzboy channel to the Caspian Sea. Climatic change, involving alternations of wet and dry cycles, is said to have accounted for only minor water level fluctuations, of the order of 4 to 6 m, against the background of the major fluctuations produced by the Amudarya course migrations. Human activity, notably irrigation, is regarded as having become significant only in modern times as a result of an expansion of irrigation works. The present abrupt decline in the Aral waterlevel (6 m from 1960 to 1977, including 2 m in the last three years) is attributed to the combination of a dry climatic cycle and greatly increased use of water for irrigation.     

综合城市灾害风险管理:创新的途径和新世纪的挑战

21世纪的城市发展绝不仅仅是经济实力、科学与信息之争,必然是包括生态环境及减灾防灾在内的城市安全度之争。可以说21世纪城市综合防灾减灾能力的高低,将成为全面衡量城市整体功能及其安是针对城市进行的全灾害的管理,它贯穿于灾害管理全过程,集中于灾害风险和承灾体的脆弱性分析并强调多层面、多元化和多学科的参与合作的全面整合的灾害管理模式。本文介绍了综合城市灾害风险管理的必要性、内涵和原则;综合城市灾害风险管理的对策和实施过程;在此基础上探讨了综合城市灾害管理的实施战略和实施途径。     

STRENGTH REDUCTION FACTORS FOR DUCTILE STRUCTURES WITH PASSIVE ENERGY DISSIPATING DEVICES

In recent years, current seismic codes started contemplating the design of structures with passive energy dissipating devices. One important issue for the rational seismic design of these devices and the structure that contains them is the formulation of numerical methods to estimate their design seismic forces. From the study of the dynamic response of single-degree-of-freedom systems subjected to accelerograms recorded in Mexico during the last two decades, expressions to estimate the strength reduction factor that should be used to reduce the elastic design strength spectra for 5 percent damping, to establish the design seismic forces for structures having different combinations of plastic and viscous energy dissipating capacities, are formulated.     

Remembering and forgetting 1974: the 2011 Brisbane floods and memories of an earlier disaster

The city of Brisbane, capital of the Australian state of Queensland, sits on a floodplain and has been struck by two devastating flood disasters in the last 50 years. This article contributes to the growing literature on disaster memory by tracing memories of a flood in 1974 as they were constructed and re‐enacted in a more recent disaster in 2011. The article examines how disaster memories shape local identities and considers how such memories influence policy and local knowledge, doing so by reference to an analysis of three forms of memory media—personal narratives, news media reporting, and built memorials. At times, memories of 1974 enabled Brisbane residents to prepare for an oncoming flood and to understand the scope of the 2011 event. Yet other memories produced a form of forgetting by positioning the earlier flood as a successfully navigated event now safely contained in the past. Findings from the analysis thus point to the importance of understanding memories of past disasters as a critical element of disaster planning and management.     

A CRITICAL REVIEW OF THE SEISMIC HAZARD ZONING OF PESHAWAR AND ADJOINING AREAS

Many of the structural engineers in Pakistan refer to the UBC code for the design of aseismic structures. On the seismic zones of international cities, the UBC code 1997 has placed Peshawar in the most severe earthquake Zone 4 similar to the high earthquake prone cities of California, Alaska, Japan, Chile, Taiwan or Turkey. These places have suffered some of the most destructive earthquakes of the past. The earthquake history of Peshawar, however, does not inform us about moderate devastation. Moreover work done on the seismic zoning of Pakistan by different national and international agencies and independent researchers present widely conflicting pictures of the seismic hazard of Peshawar. This paper critically reviews almost all of the published work done on seismic zoning, in the light of the locally available data, geology, tectonics and earthquake history of Peshawar.     

THE GEOGRAPHER AS PRACTITIONER: THE CHALLENGES, OPPORTUNITIES, AND DIFFICULTIES FACED BY THE ACADEMIC CONSULTANT

As a professional and academic geographer in a Canadian university for the last fourteen years, I have become increasingly aware that there is a growing dichotomy between pure and applied research in physical geography. This breach has been discussed by numerous prominent figures in the field. Yet it is disquieting that many published statements amount to defences of the one or attacks on the other of these two aspects of the discipline. For example, Chorley has written: 'Utilitarian approaches to geomorphology will either result in large-scale work of which the intellectually-sterile taxonomic mapping is the most depressing precursor, or in a piecemeal concentration on small-scale realist systems. The construction of [realist] models in geomorphology may not be a secure base for geomorphological theory.' To Hails, by contrast, 'There seems little doubt that geomorphologists will be asked to resolve problems created by technological innovation and engineering design in the future … [Thus] the contribution of geomorphologists might be increased if the subject was taught in such a way that students were acquainted with the necessary techniques for scientific applied studies and the needs of the market place.'     

MICROZONATION OF THE EXPECTED SEISMIC SITE EFFECTS ACROSS PORT VILA,VANUATU

The city of Port Vila, Vanuatu, is located in one of the most active seismic regions on earth. Earthquakes are felt frequently and, due to very rapid plate convergence rates, return period of large earthquakes (M>6) in the New Hebrides Benioff zone can be less than 10 years. Even though Port Vila does not lie on an identified seismic fault zone, strong motions by nearby earthquakes have to be expected due to the city's geographical location close to the plate boundary of New Hebrides convergence zone. An accurate estimation of the seismic ground motion across the city is of prime importance for urban developments and mitigation of earthquake risk. Following many examples of monitored strong earthquakes in the current century, it is evident that the local site effects may have a dominant contribution to the intensity of damage and destruction. In this study we focussed on the first stage of associating site effects and seismic hazard by preparing a microzonation map for Port Vila. The seismic microzonation of the city has been carried out to provide a detailed map of the zones that exhibit site effects in terms of resonance frequencies and approximated amplification of the ground shaking. Having in mind that these data will be used in improving building design to sustain strong ground motions, our analysis is limited to the frequency band of 1–10 Hz, corresponding to the expected resonance of different types of buildings in Port Vila. The Nakamura technique has been used to estimate site amplification effects from single station noise recordings. Interestingly, excluding one site located on an old dump zone, the amplification factors at about the 100 sites surveyed in Port Vila remain below 3 with an average well below 2 in the 1 to 10 Hz frequency band. These results suggest that there is no significant Vs velocity change in consequently layered material and that the uppermost sedimentary layers in the surveyed down town area are relatively thin. These observations are in agreement with the mapping of limestone terraces throughout Port Vila area. However, both the surface geology and results from seismic zonation indicate a thicker (up to several tens of meters) sedimentary cover around the Bauerfield airport and in the Mele terrace zone. Low resonance frequencies (around and below 1 Hz) and amplification factor of the order of 5 were observed over this large area, immediately outside Port Vila. Any building development in this area should take these results into account.     

TOIL AND TROUBLE: THE REFORM OF THE LABOR LAW

Reform of the labor law has been proposed to alleviate allegedly defective procedures and remedies in the present law. In spite of the fact that numerous violations and abuses of the existing law have taken place over the last several years and that the provisions of the existing law have been inadequate to prevent these violations and abuses, Congress has been unable to pass meaningful reform measures to deal effectively with those inadequacies. The present law allows for long delays in the settling of cases involving alleged unfair labor practices and has become, in the minds of many, a sham which does not protect the rights of workers and, indeed, allows employers to engage in unfair labor practices with very little fear of the consequences. Proponents of labor law reform argue that changes are needed to furnish adequate guarantees that the existing labor law will be effective. The lively debate in Congress over the issue of labor law reform demonstrates that it is one of the most controversial and important questions facing the nation today. Some argue that unless effective reform measures are adopted, workers will continue to labor under the existing ineffective system.     

区域产业结构演变城市化响应形态的演化规律

引入"产业结构演变的城市化响应形态"的概念,从单一城市和城市群体两个空间层次构建产业结构演变城市化响应形态的理论模型,揭示产业结构演变城市化响应形态演化的一般规律,得出以下结论:伴随着经济发展以及产业结构的优化升级,城市从单一的城市形态逐渐向城市群体空间形态演化,从都市区到城市整合体,城市群体形态不断发展演化。在现代快速化、立体化交通体系的支撑下,城市(城市群体)迅速走向区域,并最终向区域空间功能一体化形态演化。并以长春市为研究案例,进一步印证了产业结构演变城市化响应形态演化的一般规律。     

EARTHQUAKE DAMAGE SCENARIOS AND SEISMIC HAZARD OF MESSINA,NORTH-EASTERN SICILY (ITALY) AS INFERRED FROM HISTORICAL DATA

A study aimed at evaluating earthquake damage scenarios and seismic hazard of Messina using historical data, is presented. The analysis of coeval reports allowed us to reconstruct the seismic history of the city and to obtain a homogeneous earthquake site catalogue based on intensity assessed by the European Macroseismic Scale 1998. In the last 1200 years Messina was destroyed once (1908, intensity X-XI EMS) and suffered effects estimated between intensities VII and IX EMS many times (e.g. 853, 1169, 1494, 1509, 1599, 1693, 1783, 1894, 1909). Destruction or severe damage which affected the city are mainly related to earthquakes occurring in the Messina Straits and Southern Calabria, while slighter, moderate effects are usually due to shocks taking place in the seismogenic sources of SE Sicily, Gulf of Patti and Northern Calabria. The damage scenarios of the most relevant events, delineated using coeval urban plans of the city, showed that damage distribution is strongly conditioned by the different soil response. A probabilistic seismic hazard assessment was obtained by using site observed intensities: The expected intensity in a time span of 50 years (i.e. maximum intensity characterised by at least 10% exceedance probability in 50 years) is DC EMS; the expected intensity in a time span of 300 years (10% exceedance probability in 300 years) is X EMS.     

VARIABILITY OF THE CHARACTERISTICS OF WEATHER AND CLIMATE OF THE CENTRAL ECONOMIC REGION

Basic climatic elements and factors of climate formation in the Central Economic Region are assessed with a view toward improving methods of short-term forecasting. More specifically, analysis of the spatial variation of radiation, evaporation, and turbulent heat transfer, patterns of the most economically significant climatic elements; and trends in temperature and precipitation relative to long-term means sets the stage for a discussion of problems in forecasting the length of the heating season and in predicting precipitation anomalies one year into the future (translated by Andrew R. Bond).     

Change and variability in Plio-Pleistocene climates: modelling the hominin response

Research into the links between climatic change and hominin evolution has generated numerous hypotheses. In recent years, methodological refinement of, and increased research effort directed towards, reliable proxies for palaeoclimatic change have provided a growing body of data with which to test such hypotheses. Whilst many archaeologists are aware of these data, few are cognizant of the wealth of techniques developed by theoretical biologists over the last half-century to explicitly address the evolutionary consequences of adaptation to temporally heterogeneous environments. The current paper expands and adapts one such technique for use with empirical data, and applies it to a global palaeoclimatic record spanning the last five million years, in order to discern the potential impact of environmental heterogeneity on hominin evolution during this period. Of particular interest are the contributions of climatic change, associated with directional selection, and climatic variability, associated with selection for phenotypic plasticity. At this macro-scale, results suggest an early peak in selection for plasticity at approximately 2–2.7 mya, combined with three major shifts in directional selection at approximately 3.3–3.4, 1.4–1.5, and 0.5–0.6 mya. These results are employed to relate the fossil and archaeological records to a number of environmental hypotheses of human evolution. In particular, it is argued that the origins of the genus Homo and the spread of Oldowan technology are associated not with a major turnover pulse, but with a period of selection for phenotypic plasticity.     

Macrophysical climatic modeling of Africa’s late quaternary climate: Site-specific, high-resolution applications for archaeology

Macrophysical climatic modeling (MCM) is based on the relationship between large-scale atmospheric dynamics and synoptic climatology to develop simulations of late Pleistocene and Holocene climate in specific localities. Climatic events are calculated at 200-year intervals for the last 14,000 and 500 years for the period from 14,000 to 40,000 B.P. The model has been applied to more than 200 localities in Africa. We present examples from different parts of the continent at locations of archaeological significance. The results indicate that the transition from glacial maximum to postglacial conditions shows both temporal and inter- and intraregional variability. In addition to long-term differences among early, middle, and late Holocene climatic regimes, the model also shows incidences of sharp, abrupt events at some intervals. The applications of MCM invite comparison with inferences based on proxy data and assist in formulating and cross-examining socioecodynamic models based on climatic change, e.g., the continuity of cultural interactions along the Mediterranean littoral, the emergence and spread of cattle pastoralism, and the depopulation of the Sahara during the glacial maximum.     

A radiocarbon chronology for the aceramic shell-middens of coastal Oman

Our knowledge of the prehistory of coastal Oman has greatly increased during the last ten years. This article considers the radiocarbon chronology of the aceramic shell-middens scattered along the coast between Muscat, to the north, and Shuwayr, to the south. The appearance of these middens seems to correspond to the climatic deterioration that, according to more recent results, took place around the middle of the seventh millennium BP. The number of sites seems to have increased since the beginning of the actual arid phase, around 6000 BP.     

Droughts as random events in the Maya lowlands

Because the values of most of the parameters controlling the occurrence and severity of a drought in a given location are unknown, and no periodicity has been observed, droughts can be considered random events. Running a random number generator within the limits of the annual rainfall variability relevant to the Maya lowlands, and defining a “Lean Year”, it is observed that strings of lean years occur quite frequently. Defining “Severe Drought”, “Disaster”, and “Catastrophe” based on the length of these strings, it is observed that a severe drought occurs on average every 32 years, a disaster occurs on average every 130 years, and a catastrophe on average every 500 years. These values fit the measured variability of the Yucatan climate, as observed in lake core sediments and in the post conquest written records. It also fits the average occurrence of “megadroughts” in the US Great Plains.The fit between the random occurrence model and the actual, “measured” occurrence of droughts supports the notion that for all practical purposes, droughts had been random events in the Maya region and could not be predicted. The lack of evident periodicity could be one of the reasons why means for long-term storage of food products were not developed there. It may also have affected the relationship between the priesthood and the general populace in that region.Since the method described here can be applied to any climatic region once the rainfall variability and the sensitivity of the local agriculture are known or can be estimated, if similar results are found they may probably have affected other regions with other ancient cultures in a similar way.     

From riches to rags: organic deterioration at Star Carr

The 11,000-year old lake edge archaeological site of Star Carr in the Vale of Pickering of North Yorkshire is one of the most famous Mesolithic sites in Europe, and one of the earliest, dated to the period of climatic warming that immediately followed the final termination of the last ice age. One of the main reasons for this international importance is the richness of its organic artefacts, faunal assemblage and environmental data. However, recent investigations have demonstrated that these organic remains have severely deteriorated over the last 60 years due to the decay and acidification of the surrounding peat. This paper presents research into the effects on the bone (histological analysis using light and polarising microscopy, and Transmission Electron Microscopy, bulk collagen analysis, and amino acid analysis), antler (visual and metrical analysis, loss on ignition and Scanning Electron Microscopy) and wood (visual analysis, decay assessment tests and Scanning Electron Microscopy).     

BAYESIAN MODELING OF THE OCCUPATION SPAN OF THE AVERBUCH SITE IN THE MIDDLE CUMBERLAND DRAINAGE,TENNESSEE

Abstract

The application of Bayesian models to suites of radiocarbon dates can provide important refinements over standard approaches toward calibration and seriation of dated feature contexts. We have modeled a number of older radiocarbon dates submitted in the 1980s along with a recent set of accelerator mass spectrometry dates from the Averbuch site (40DV60), a Mississippian village in the Middle Cumberland Region of Tennessee occupied in the fourteenth and fifteenth centuries A.D. The results of these analyses demonstrate that even within its short lifespan of ca. 200 years, the village underwent fundamental organizational changes. These shifts appear to be responses to climatic deterioration and an upsurge in regional violence.     

OBSIDIAN IN THE MEDITERRANEAN AND THE NEAR EAST: A PROVENANCING SUCCESS STORY

Obsidian provenancing studies comprise one of the most productive and successful research programmes of archaeological science. Obsidian characterization has been successful because workable obsidian is homogeneous on a small scale, analysable by a large number of methods, and is restricted to a small number of mainly readily distinguishable geological sources. Analytical, dating, source, and trade studies within the western Mediterranean, central and eastern Europe, the Aegean, and Anatolia and the Near East during the last 30 years or so are reviewed. Research has shown that distributions are mainly separate in the four regions examined, and that obsidian was traded up to 900km in the prehistoric period. Publications on obsidian in the areas under review reached a peak of frequency in the later 1970s and 1980s, but have now decreased in number. This may reflect changing fashions in archaeometric studies, and a current lack of routine application of the provenancing methods developed.     

SEISMIC HAZARD ASSESSMENT OF UNITED ARAB EMIRATES AND ITS SURROUNDINGS

This paper presents the seismic hazard assessment and seismic zoning of the United Arab Emirates (UAE) and its surroundings based on the probabilistic approach. The area that has been studied lies between 50°E-60°E and 20°N-30°N and spans several Gulf countries. First, the tectonics of the area and its surroundings is reviewed. An updated catalogue, containing both historical and instrumental events is used. Seismic source regions are modelled and relationships between earthquake magnitude and earthquake frequency is established. A modified attenuation relation for Zagros region is adopted. Seismic hazard assessment is then carried out for 20 km interval grid points. Seismic hazard maps of the studied area based on probable Peak Ground Acceleration (PGA) for 10% probability of exceedance for time-spans of 50, 100 and 200 years are shown. A seismic zone map is also shown for a 475-year return period. Although the results of the seismic hazard assessment indicated that UAE has moderate to low seismic hazard levels, nevertheless high seismic activities in the northern part of UAE warrant attention. The northern Emirates region is the most seismically active part of UAE. The PGA on bedrock in this region ranges between 0.22 g for a return period of 475 years to 0.38 g for a return period of 1900 years. This magnitude of PGA, together with amplification from local site effect, can cause structural damage to key structures and lifeline systems.     

Holocene land-use evolution and associated soil erosion in the French Prealps inferred from Lake Paladru sediments and archaeological evidences

A source-to-sink multi-proxy approach has been performed within Lake Paladru (492 m a.s.l., French Prealps) catchment and a 6-m long sediment sequence retrieved from the central lacustrine basin. The combination of minerogenic signal, specific organic markers of autochthonous and allochthonous supply and archaeological data allows the reconstruction of a continuous record of past human disturbances. Over the last 10,000 years, the lacustrine sedimentation was dominated by autochthonous carbonates and the watershed was mostly forest-covered. However, seven phases of higher accumulation rate, soil erosion, algal productivity and landscape disturbances have been identified and dated from 8400 to 7900, 6000 to 4800, 4500 to 3200, 2700 to 2050 cal BP as well as AD 350–850, AD 1250–1850 and after AD 1970. Before 5200 cal BP, soil erosion is interpreted as resulting from climatic deterioration phases towards cooler and wetter conditions. During the Mid-Late Holocene period, erosion fluxes and landscape disturbances are always associated with prehistorical and historical human activities and amplified by climatic oscillations. Such changes in human land-used led to increasing minerogenic supply and nutrients loading that affected lacustrine trophic levels, especially during the last 1600 years. In addition, organic and molecular markers document previously unknown human settlements around Lake Paladru during the Bronze and the Iron Ages.