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Meander erosional banks of fifth and sixth order southwestern Wisconsin streams having drainage areas of twenty square miles (30 km2) or less frequently reveal three distinct sedimentary sequences. The basal unit of coarse textured debris is thought to represent bad load sediment of a prior channel active near the terminus of a mid-Holocene drought about 6,000 years B. P. A silty clay series over the coarse layer is interpreted to have been derived by vertical accretion extend from the middle series to the current surface, and mainly result from increased flooding related to modern land use practices. The recent man-induced change in channel morphology is analogous to natural adjustments produced by Holocene climatic fluctuation, and suggests that temporal aspects of channel and floodplain evolution may be described by a step function model. [ABSTRACT FROM AUTHOR]

Presents environmental news and commentary briefs. Report that Dr. Reid Bryson of the University of Wisconsin told two U.S. Senate agriculture sub-committees last week that the era of surpluses and benign climate is over due to the effects of man-made pollution and volcanic activity; Discussion of the interaction between prey and predator from an ecological perspective; Report that Thomas Weaver described at a meeting of the American Physical Society a new nuclear fission pathway for obtaining enormous amounts of energy without producing radioactive byproducts; Report that seven West African countries have adopted a $120 million plan to eradicate river blindness among people living in the Volta river basin; Discussion of the search for protein-rich dietary alternatives to meat; Discussion of ecological problems in Greece; Report that the United Nations has convened a World Population Conference; Report that a unified transport scheme connecting the cities of Munich and Hanover in Western Germany is being considered by planning authorities; Discussion of efforts by the Australian government to decentralize its cities.

The article examines the study of vegetational history of post-glacial period in Great Britain. The data from stratigraphy shows that plant remains and the pollen analyses from the site contain lake muds such as Betula, Pinus and Salix. During the Late-glacial period, there was an evidence of a cold climate and of a vegetation of open birch woodland or open vegetation with copses and a rich herbaceous ground flora as well. Thus, the evidence for a climatic oscillation marked a general climatic amelioration of the Post-glacial period.

The article discusses the evolution of modern plant ecology in Great Britain. According to the author, the foundations were laid earlier and the conceptions of plant formations were developed by famous phytogeographers as Humboldt and Grisebach in the first half of the century. Furthermore, its modern meaning was determined by the publication of Warming in 1895 on "Plantesamfund: Grundträk af den ökologiske Plantegeografi." It was translated into German and widely used in England and America which it played as an important part in stimulating fieldwork for both countries. In 1898, A. F. W. Schimper published "Pflanzengeographie auf physiologischer Grundlage," which focus on the types of vegetation throughout the world and discusses the climatic and edaphic factors.

The article focuses on the endemic trees of the British Guiana Peneplain. It describes the situation, climate and topography British Guiana and the distribution of the main climatic associations. It also notes the influence of climate on the distribution of other species and the prevalence of endemism in the Guiana flora through the analysis of the local and general range of forty of the commonest trees. It also states the likelihood of the endemic species of the Guiana flora which have evolved in the highlands that borders the western and southern limits of the peneplain.

The article presents studies on the vegetation of Nottinghamshire, England. This paper explored the geological structure of the ecology of the Bunter Sandstone and superficial deposits. Different conditions were also taken into account including the climatic and edaphic focusing on the flora of the Sherwood forest. Different plant communities were subjected for thorough investigation recording the botanical information and general account of vegetation. The result of the experiment is discussed in brief.

The article examines the role of climatic change and agricultural decline in the fall of Rome. According to Professors Liebig and Simkhovitch, in the days of the Roman Republic a vast portion of land was enough to support families in the region. Agrarian problems took place by the second century before Christ when, under the leadership of Scipio, grain began to be distributed from state granaries to poor citizens. As a result, many families became poverty stricken and tenants fell into heavy debt. On the other hand, climatic facts of historic times revealed how climatic change contributed to the fall of Rome.

The relationship of climate to land-surface morphology and genesis has been investigated by numerous writers for well over half a century. Such studies have focused in part upon interpreting erosional cycles, but more importantly they have to an increasing degree been oriented toward understanding the areal variation of specific surface forms and geomorphic processes. Especially pertinent to the geographer are recent attempts in the United States, and particularly by Julius Büdel in Germany, to use climatic influence as a basis for establishing morphogenetic and climato-genetic regions. [ABSTRACT FROM AUTHOR]

The study of climatic change is a fascinating and elusive exercise. Especially as the record of earth history begins to merge with the beginnings of human civilization, profoundly significant questions hinge on the dynamic relationship between a changing physical environment and the adaptive qualities of early man and his heirs. It has been suggested from more than one field of enquiry that climatic change was art important factor in the first dispersion of the human progenitor from the deforested plains of central Asia, and that vagaries of climate have ever since exercised a controlling influence on the nature and location of civilizations which man at different periods has established.

The article focuses on the physical aspects of city planning. Physical factors are those which are inherent in or emanate most directly from the facts of the three-dimensional world. To simplify their exposition, physical factors are divided into three general categories, including long-range, medium-range, and short-range. Climatic changes, natural erosion and, the types and quantities of natural vegetation, all constitute the long range physical factors. Such long-range physical influences are as yet either so unresolved or involve such vast cycles of time that their greatest importance for town planning lies in their function as roots for deductions of more immediate relevance.

This article illustrates the climatic cycle of an average length of thirty-five years in the U.S., as described by E. Brückner, professor of geography in the University of Bern, Bern Switzerland. The great built of Brückner's material is drawn from European. This study for the U.S. has shown that by using definite observational material for a large area, a number of epochs of maxima and minima come to light, some of which fit into the Brückner Cycle, but many do not. The time between two maxima or two minima may vary between twenty and fifty years.