A MAP OF URBAN PLACES,U.S.S.R., 1970

Abstract

Figures from the 1970 Soviet Census provide an abundance of information on population changes in the U.S.S.R. Of special note is the process of urbanization and a noticeable concentration of urban growth in the hitherto largely rural zones of western Russia. A large map of urban places in 1970, designed primarily for classroom use, accompanies the text (see inside back cover). The map utilizes a special stippled-sphere technique to allow a three-dimensional effect without half-tone reproduction.     

Book Review: Landscape Erosion and Evolution Modeling. Russell S. Harmon and William W. Doe III,eds., Kluwer Academic/Plenum Publishers,New York, 2001, xxi, 540 p., ISBN 0-306-46718-6, U.S. $120.00

Natural Resources Research -     

Late Wisconsinan and Holocene diatom stratigraphy from Amarok Lake,Baffin Island,N.W.T., Canada

Diatom analyses from the longest continuous record of lacustrine sedimentation in the eastern Canadian Arctic indicate four phases of lake development during the past 20000 years. PlanktonicAulacoseira taxa are dominant between 20 and 10 ka and during the Neoglacial. The earliest Holocene is characterized byFragilaria, whereas benthic acidophils (e.g.Frustulia, Brachysira & Eunotia spp.) dominate sediments of early to mid Holocene age. Ordination by correspondence analysis illustrates stratigraphic changes in diatom life form and pH tolerances, and these are related to both regional paleoclimatic conditions and local edaphic factors. The occurrences of planktonic floras during the cold Late Foxe and Neoglacial periods suggests that, even at these times, the lake became ice free during summer. The interplay of increased runoff as a mechanism of ice disintegration and enhanced silicon supply by erosional processes (corroborated by the more clastic nature of the sediments during these periods) likely enabledAulacoseira to flourish. Early and mid Holocene limnological regimes were more strongly controlled by lake authigenic processes.This paper was presented at the VI Palaeolimnology Symposium, held at Canberra in April 1993. Dr. Mark Brenner guest edited this contribution.     

Comment on “Burrough,S.E., Breman,E., and Dodd,C., 2012. Can phytoliths provide an insight into past vegetation of the Middle Kalahari paleolakes during the late Quaternary? Journal of Arid Environments 82, 156–164”

This is a comment on the article of Burrough et al. (2012) in which they present a palaeoclimatic reconstruction based on phytolith assemblages from sandy shoreline deposits in the Makgadikgadi Basin, Botswana. While this work highlights a potentially important paleoenvironmental archive in a notably data-poor region, there are several fundamental short-comings in the Burrough et al. work in terms of the calibration of their findings with plant distributions and ecology. Not recognising these limitations in their article, the authors apply palaeoenvironmental indices that are regionally inappropriate, and which we argue in turn render their paleoenvironmental interpretations invalid. With no regionally specific reference collection being established, it may be the misidentification of phytolith morphotypes that has created the paradox that is posed by Burrough et al.     

Magnetic measurements of recent sediments from Big Moose Lake,Adirondack Mountains,N.Y., USA

Measurements of anhysteretic (ARM) and isothermal (IRM) remanences in cores 6 and 8 from Big Moose Lake reveal evidence for changes in magnetic mineralogy and grain size within and between the two cores. It is proposed that changes in the strength and demagnetization characterizations of the IRM reflect the accumulation of atmospherically deposited magnetic minerals resulting from industrial processes. The record of magnetite deposition especially in Core 6 parallels that for coal soot at the site. In both cores, the record of haematite deposition parallels that for several anthropogenic indicators.This is the fourth of a series of papers to be published by this journal which is a contribution of the Paleoecological Investigation of Recent Lake Acidification (PIRLA) project. Drs. D. F. Charles and D. R. Whitehead are guest editors for this series.