THE MECHANISM OF DEVELOPMENT OF THE VOLGA DELTA AND ITS GROWTH PROSPECTS

The delta of the Volga River on the Caspian Sea is a highly dynamic form, whose growth has been affected by a combination of physical and human factors. Rapid delta growth in recent years has resulted in a deterioration of both physical and economic conditions (navigation problems, inadequate moisture supply, overgrowing of shallows with vegetation, loss of spawning grounds). Regression analysis yields a number of relationships between the inflow of water and suspended sediments, on the one hand, and delta growth, on the other hand, with a distinction between periods of a lowering of the Caspian Sea level and relative stability. The regression equations are used to project the likely future evolution of the delta. The only combination of conditions that is likely to limit further delta growth by the year 2000 is the stability of the Caspian Sea level and a period of average moisture supply. In all other cases, the delta is likely to continue its undesirable advance.     

ON THE CONNECTION BETWEEN LEVEL FLUCTUATIONS IN THE CASPIAN SEA AND THE ARAL SEA

Although both the Caspian and Aral Sea basins are affected by fluctuations in the general moisture conditions affecting the Northern Hemisphere, the two drainage basins react differently to identical moisture changes both over the long term and over the short term. Over the short term, a shift in wet periods has been observed between the European part of the USSR, which contains the Volga basin draining into the Caspian, and western Asia, which contains the Aral Sea drainage basin. Since there is a direct relationship between general moisture conditions and level changes, the short-term level fluctuations would be heterochronous (out of phase) in the two seas. Over the long term, the comparison is complicated by the fact that Caspian drainage derives mainly from snow meltwater in the Russian plain while Aral Sea drainage derives from a combination of snow and glacier meltwater. Glacier runoff tends to increase in dry, warm periods and to decrease in wet, cold periods of glacier growth, while snow is related directly to general moisture conditions.     

ON THE PROBLEM OF REGULATING THE REGIME OF THE CASPIAN SEA

In an effort to stabilize the declining level of the Caspian Sea, it has been proposed that evaporation from the water surface be reduced by decreasing the size of the sea through construction of a dam in the northern portion. Data on the geology and hydrology of the Caspian Sea bed suggest that the construction of a dam might have undesirable consequences not only for the northern fisheries basin but for the sea as a whole. The findings are based on the presence of salt domes on the bottom of the northern Caspian Sea. An influx of highly mineralized subsurface waters along faults associated with the salt domes as well as leaching of salt from the structures themselves may threaten to raise the salinity of the northern fisheries basin to intolerable magnitudes. The presence of a man-made dam, in the author's view, would also interfere with the natural circulation of water, threatening contamination of deeper layers of the Caspian Sea with hydrogen sulfide, as has happened in the case of the Black Sea. [For a discussion of the Caspian Sea problem, see Soviet Geography, November 1972.]     

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.     

The Transformation of the Caspian Sea

The author reviews the problem of the level fluctuations of the Caspian Sea, particularly the steady drop since 1929. The drop in level is affecting many key sectors of the regional economy. Among several remedial schemes is a plan for diverting the rivers of northern European Russia to the Caspian, and a project for a localized regulation of the level of the Caspian Sea.     

Khazaria and the Terek (Landscape and Ethnos,II.)

The author analyzes a functional relationship between the historical fate of the Khazar people of the Caspian steppe and changes in the landscape produced by an alternation of wet and dry cycles and changes of the Caspian Sea level. A previous article of this series appeared in Soviet Geography, June 1964.     

Of stones and bones: Interpreting site function in the Upper Paleolithic and Mesolithic of Western Europe

Upper Paleolithic and Mesolithic excavations have usually yielded both artifacts and faunal remains in a variety of environmental settings across a latitudinal range from Belgium to Portugal. In some cases there seem to be functional relationships within levels between ungulate species and skeletal elements on the one hand and associated lithic and osseous artifacts on the other. In other cases—perhaps because of their nature as occupational and depositional palimpsests—the relationships are murkier. Examples examined here include La Riera and El Mirón caves (coastal and montane Cantabrian Spain, respectively), Dufaure rockshelter (Pyrenean lowland France), Magrite cave, Pape rockshelter, and Bois Laiterie cave and the Huccorgne open-air site (Ardennes upland, transitional zone, and central plateau of Belgium, respectively), and the Vidigal shell midden (coastal southern Portugal). The interpretation of site function (e.g., multi-purpose residential site, specialized logistical camp, or transit bivouac) is a matter of pragmatic, interdisciplinary, situation-specific analyses, and parsimony.     

Khazaria and the Caspian (Landscape and Ethnos,Part I)

The author combines the techniques of historical geography, archeology, and paleogeography to investigate the distribution of the Khazars, a people settled in the Volga delta from the sixth to tenth centuries. Data on Caspian Sea level changes, obtained in part from study of the Derbent wall, are correlated with known political events in the history of the Khazars. A history of settlement of the Volga delta is reconstructed.     

Locating Land Use at Neolithic Çatalhöyük,Turkey: The Implications of 87Sr/86Sr Signatures in Plants and Sheep Tooth Sequences

We evaluate local versus distant land‐use models at Neolithic Çatalhöyük, central Anatolia, using strontium isotope analysis of sheep tooth enamel and charred plant remains. Interpretation of strontium in sheep tooth sequences is constrained by previous oxygen isotope work, which largely excludes summer movement to the mountains but cannot distinguish between herding on the plain and the closest upland‐zone, Neogene limestone terraces. We establish a baseline contrast in modern plant strontium values between the plain and terraces and infer predominant herding on the plain from seven sheep tooth sequences. Archaeobotanical plant strontium values exclude the use of the terraces for cultivation and foraging. Relatively local crop and sheep management, plausibly intensive and integrated to some degree, given limited dry ground, appears likely on the basis of this pilot study.     

Monks and Local Communities: The Late-medieval Landscape of Troed y Rhiw,Caron Uwch Clawdd,Ceredigion

Abstract

In a zone of improved upland pasture some 2 km east of the Cistercian monastery of Strata Florida (Ystrad Fflur), Ceredigion, are the earthwork remains of a 'sheepcote' and four abandoned medieval farms, one probably originating as a monastic sheep-handling station. Documentary evidence and field observation suggest that these farms have preserved their late-medieval forms in a relatively unmodified state. Three were apparently situated along a contemporary ffridd boundary (head dyke) that separated a zone of pasture and perhaps arable land from mountain pasture. We cannot establish the relationship between the 'sheepcote' and the 'farms' through field observation alone, nor do we know the absolute age of the ffridd boundary. Our paper describes and briefly discusses the character and local context of the area defined by the latter. The pattern of land-use is comparable to that in Swaledale (North Yorkshire), an area that has been discussed on the one hand in terms of patterns of townships (hamlets) and their land-use zones, and on the other in terms of monastic enterprise and the identification of 'vaccaries'. In the study of 'monastic landscapes', we risk becoming preoccupied with estate economies and the identification of 'tool-kits', at the expense of dealing with the complexity of relationships between monasteries and local communities.     

Weakening processes in thrust faults: insights from the Monte Perdido thrust fault (southern Pyrenees,Spain)

The Monte Perdido thrust fault (southern Pyrenees) consists of a 6‐m‐thick interval of intensely deformed clay‐bearing rocks. The fault zone is affected by a pervasive pressure solution seam and numerous shear surfaces. Calcite extensional‐shear veins are present along the shear surfaces. The angular relationships between the two structures indicate that shear surfaces developed at a high angle (70°) to the local principal maximum stress axis σ₁. Two main stages of deformation are present. The first stage corresponds to the development of calcite shear veins by a combination of shear surface reactivation and extensional mode I rupture. The second stage of deformation corresponds to chlorite precipitation along the previously reactivated shear surfaces. The pore fluid factor λ computed for the two deformation episodes indicates high fluid pressures during the Monte Perdido thrust activity. During the first stage of deformation, the reactivation of the shear surface was facilitated by a suprahydrostatic fluid pressure with a pore fluid factor λ equal to 0.89. For the second stage, the fluid pressure remained still high (with a λ value ranging between 0.77 and 0.84) even with the presence of weak chlorite along the shear surfaces. Furthermore, evidence of hydrostatic fluid pressure during calcite cement precipitation supports that incremental shear surface reactivations are correlated with cyclic fluid pressure fluctuations consistent with a fault‐valve model.     

‘Torrents of Terror’: the August 1998 Storm and the Magnitude,Frequency and Impact of Major Floods in the Illawarra Region of New South Wales

The Illawarra Region some 80 kilometres south of Sydney is characterised by a prominent coastal escarpment that rises to 700 m within 12 km of the coast and forms a locus for frequent, high intensity rainfall events. One of the most recent recorded events occurred on 17 August 1998 with rainfall intensities at several pluviometers exceeding 120 mm hr^‐1 over a duration of one hour, with up to 249 mm falling in 3.5 hours during the main storm burst. Detailed pluviometer data indicate that the storm was non‐stationary and moved down catchment producing a widespread zone of 120 mm hr^‐1 intensity rainfall over a 30 minute duration across mid‐lower catchment areas after similar intensity but longer duration rainfall in catchment headwaters. Slope‐area reconstructions of peak discharge indicate that small catchments on the escarpment within the zone of maximum intensity experienced close to 100% rainfall‐runoff relationships, with peak discharges correlated to short duration (<1 hr) peak rainfall intensities. Widespread erosion occurred particularly where urban development had encroached on natural water courses. Debris/hyperconcentrated flows originating from both anthropogenic and natural sediment sources caused damage to urban areas. This paper provides an overview of the spatial and temporal characteristics of the 17 August 1998 storm, the hydrologic and geomorphic response of the streams, and the nature of damage to urban areas. It reassesses the frequency of recent high‐magnitude rainfall/flood events in the region, discussing the relationships between rainfall intensities, estimates of flood magnitudes and stormwater channel capacities.     

Using multivariate statistics and fuzzy logic system to analyse settlement preferences in lowland areas of the temperate zone: an example from the Polish Lowlands

The influence of relief, as well as other environmental features such as soils or the hydrological regime, on prehistoric settlement patterns is commonly accepted. Settlement patterns and preferences changed over time in different areas, so it is difficult to formulate general rules of human behaviour throughout history. In lowland areas of the temperate zone, which lack radical relief changes and have widespread access to water resources, specific settlement preferences and significant changes in these preferences are difficult to interpret.New methods developed to address the problem of the settlement transformations as a result of prehistoric settlement and economic processes using multivariate statistics have been adapted for the middle part of the Great Poland Lowland. In this region, data from the Polish Archaeological Record Project database have been used.Models of the dependence between geomorphological features and settlement intensity form the basis for estimating changes in prehistoric settlements. The degree of preference (or avoidance) is a nonparametric function of the number of archaeological sites observed in the area relative to the number of sites expected from a completely random pattern. The most crucial factors for settlement are distance to plateau edges, distance to water bodies, and the wetness index. The results show that the entire investigated area is more or less suitable for settlement, but the most occupied terrains are the areas near plateau edges.     

Some Conclusions about the Geography of Cities and the Urban Population of the USSR based on the Results of the 1959 Census

The author acknowledges that climatic factors and man's activity are the principal causes of fluctuations in the level of the Caspian Sea. But he maintains that tectonic processes, such as crustal movements, play a significant part and gives evidence of correlations between geological processes and changes in the sea level.     

The Problem of Transformation and Utilization of the Water Resources of the Volga River and the Caspian Sea

Abstract

The authors review expected water requirements within the Volga-Caspian basin for industry, agriculture, fisheries and municipal uses and plans for the diversion of the streams of northern European Russia to the south to support the level of the Caspian Sea. They suggest that the diversion of part of the flow of the northern streams and isolation of the natural evaporation basin of the Kara-Bogaz-Gol will be sufficient to maintain the Caspian Sea level at ?28 meters. Previous articles on the Caspian problem appeared in Soviet Geography, September 1961, January 1962, and June 1963.     

PRINCIPAL TRENDS AND PROSPECTS OF THE USE OF WATER RESOURCES IN THE USSR

The increasing demand on water in the Soviet Union and the problem of assuring water quality require the construction of long-term water-management balances by drainage basins. These balances, based on predicted demand and water availability, would suggest the need for water-management projects within basins and interbasin transfers. Water needs would be evaluated both in terms of water requirements by categories of users and in terms of water quality. The most crucial regional problems involve the increasing shortage of water in Central Asia (with the prospect of interbasin transfer from Siberia) and in southern regions of the European USSR (with the problem of diverting water southward from the northern runoff slope). The Caspian Sea is expected to require a supplementary inflow of 80 to 100 cubic kilometers a year by the end of the century if the decline of its waterlevel is to be arrested. But southward diversion of northern waters is not expected to add more than 50 to 70 km³ at best, with a possible saving of an additional 10 to 20 km³ through decline of evaporation from a reduced Caspian Sea surface. The preservation of conditions in the Sea of Azov, the Aral Sea and Lake Balkhash pose additional water problems. [The senior author died in October, 1974].     

THE MORPHOMETRY OF THE CASPIAN SEA BASED ON CONTEMPORARY DATA

Differences in available data on the area of the Caspian Sea are analyzed, and an effort is made to explain them. The differences are particularly pronounced in the shallower northern portion of the sea, where the drop of the sea level over the years has produced more significant changes in shoreline configuration. Greater use of space imagery is urged in determining changes in shoreline configuration, and the setting of “geographical standards” is proposed to avoid continuing confusion in published data. The technical problem of calculating the physical water area, including surface roughness produced by wave motion, is discussed.     

Local Land Use Plans and the Implementation of New Urban Development

This article, based on case studies of plan 'construction' in the 1980s for large scale residential development near Bristol, England and in Poitiers, France, argues that the form and content of these local land use plans were the product of the coordinative planning strategy adopted. This strategy embodied assumptions about implementation and established relationships between development interests and the plan 'constructors' during the process of plan preparation. These relationships in turn were a consequence of the contrasting powers and resources available to local government to ensure the implementation of local land use plans.     

CHANGES IN THE LEVEL OF THE CASPIAN SEA AND THE POSSIBILITY OF FORECASTING THEM

A second paper devoted to problems of predicting the future level of the Caspian Sea attempts, as did the first, to discount overly simplistic explanations for its nearly century-long decline and recent slight rise. Long-term climatic changes within the drainage basin of the Caspian and the resultant change in discharge of tributary rivers are proposed as the basic mechanism controlling sea level fluctuations and not, as argued in the popular press, tectonic movements, groundwater discharge variations, or the damming of the Kara-Bogaz-Gol. Various models for predicting future levels are compared, although no specific forecasts are made (translated by Andrew R. Bond).     

Policy Interaction in the Provision of Unemployment Insurance and Low-Income Assistance by State Governments

In this paper we investigate empirical relationships between Unemployment Insurance (UI) and welfare policies using a unique database covering 48 states annually from 1973 through 1989. We first document substantial variation across states in UI program outcomes. Having established that UI is so variable, we explore the simultaneous interaction between UI and Aid to Families with Dependent Children (AFDC), Medicaid, and total state and local welfare spending. Our econometric results indicate substitution between the two cash assistance programs, AFDC and UI, by state governments. On the other hand, states that operate relatively generous UI programs also tend to allocate more resources to Medicaid and other in-kind, low-income assistance programs.