Search

The article discusses the study which assesses the evidence from British hepatics with discontinuous distribution outside the British Isles in relation to the history of the British flora. In this paper, British hepatics showing disjunction in their world distribution are classified in six groups including mediterranean element, disjunct-temperate element and the American element. It is concluded that the hepatics considered do not form a homogeneous group and their distribution patterns all appear to be explicable in terms of post-glacial climatic change without invoking in situ survival through glaciation.

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 presents information about several papers on social history of the Medieval period. Bringing together from the Pergamenos collection of the Archives of the Crown of Aragon 91 documents concerning the Vivas family of Provençals, a neighboring village to Barcelona, Spain between the years 986 and 1084, M. Pierre Bonnassie has been able to follow, with a precise detail very rare for this period and with a considerable insight, the rise of a well-to-do peasant family entering the ranks of the aristocracy. M. Georges Duby, for his part, has studied "Au Xlle siècle: les "jeunes" dans la société aristocratique." He shows that the fate of this horde abandoned to the conquest of glory, profit and female prey by noble houses wishing to relieve the excess of their expansive power, a group very prone to violent death, is not without interest for economic history. In his paper, Mile Emilienne Demougeot has tried to trace a relation between climatic variations and invasions, those invasions at least which occurred in the West up to that of the Cimbrians, Teutons and Goths, at the end of the second century B.C.

Examines the complexity and dynamics of climatology. Investigation of the three climatic methodologies; Distinction between dynamic and synoptic climatology; Description of climates.

Discusses the climatic maps of proper China and Manchuria according to the Thornthwaite 1948 classification. Formula for computing the potential evapotranspiration; Presentation of climatic conditions; Classes of maps presented by Thornthwaite.

The article describes the microclimates of the Olokemeji Forest Reserve as a prelude to studies on seasonal changes in the vegetation in Nigeria. This description is based on rainfall and temperature data from Olokemeji and for other climatic elements, on data from Ibadan. The mean length of dry periods is less than 4 days during the wet season and rises to over 50 days during the dry season. The results show that Olokemeji has a climate typical of it area of the country and of the forest/derived savanna boundary area in west Africa.

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.

This article describes a chromatic dispersion procedure for refractive index determinations on glass fragments. Chromatic dispersion represents the difference between the refractive indices of a given substance for light of different wave lengths. The value for the chromatic dispersion of a material depends upon temperature and the nature of the substance. In the absence of special equipment it is not a simple matter to accurately determine the dispersion of a substance, it is still more difficult to determine the change in value with a change in temperature. Although temperature changes will affect the color halo, tests indicate that work performed at room temperature in a non-temperature-controlled cell is as satisfactory as that performed under constant temperature conditions. Although a number of temperature-variation devices have been described in the literature on immersion techniques, it appears that they are not too generally utilized in criminalistics laboratories. Since preparation of the earlier paper on this subject, the writer has constructed a unit for this work which may be of interest. It is designed for use in connection with the procedure previously described, and will be found a most useful accessory to anyone doing refractive index work by that method.

The article presents a reprint of the article "Can We Control the Arctic Climate," by P. M. Borisov, which appeared in the "Soviet" journal. It discusses the problems of the climatic changes in Russia and other places in the Arctic regions which are caused by the expanding populations. The author examines the efficacy of transporting Atlantic Ocean water across the Arctic Basin to improve the climate in the areas.

Pollen analysis of three sites on Wilsons Promontory provides a vegetation record from 6000 B.P. to the present day. No extensive changes in the vegetation have been found over this time period, but local and regional variations in the extent of communities may imply small climatic changes. Moister conditions than at present seem to have prevailed earlier than 4500 B.P., followed by a drier phase till less than 2000 B.P., when an increase in moisture gave conditions similar to those of today. Some evidence exists to support the theory of a relatively steady sea level close to the present level over the last 6000 years along the western Wilsons Promontory coastline. [ABSTRACT FROM AUTHOR]

The mean temperature for the Northern Hemisphere had a warming trend from 1890 to 1950 and a cooling trend since 1950. The eastern and central United States had colder temperatures in 1961–1970 than in 1931–1960. The temperature changes were associated with an adjustment of hemispheric circulation from more frequent zonal flow between 1900 to 1950 to more frequent meridional flow since 1950. Regional variations in magnitude and direction of the change were largely related to position in relation to the upper air westerly wave pattern. Time series of individual circulation indices tend to resemble the step function model of climatic change. [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 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 gully (or arroyo) in the American Southwest has attracted scientific attention for more than three score years. In the first phase, gullies tended to be viewed as the result of changes in the vegetation cover brought about by man and his live-stock. Later, the discovery of prehistoric gullies led to a shift of attention to possible climatic causes and to the elaboration of a widely accepted model relating climatic events to erosion-deposition. In the last five years, the study of the pollen record has inspired a new model of interpretation, different in important respects from the older one, The examination of New Mexican gullies suggests that the new model has certain advantages, but that in fact our knowledge is still extremely hypothetical. Lacking is a detailed comparison of the local environments under which erosion-deposition takes place, and lacking also is a documented history of the gullies. An attempt is made to compare the local environments of gullies in New Mexico and, in the case of the Rio Chaco and the Rio Puerco, to document the history of their gullies in some detail.

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]

In the study of climate, mean values of variable quantities are used as representations of the changing phenomena of nature. Two problems are considered in this article, namely, vegetation change and climatic change. It is proposed that a climatically determined vegetation cover may undergo change due to variations concealed within the usual climatic mean and so lead to false hypotheses. The second argument, which occupies most attention in the article, is that climate is varying continuously and randomly solely because of endogenous processes, of which the fluctuations that produced the ice ages are spectacular manifestations.

Examines the evolution of a landscape in Southern California. Consistency of the climate in the area; Duration of the wet and dry cycles; Effect of the climate on the environment; Occurrence of a climatic fluctuation in the area.

Reports on the factors influencing the failure of wheat, a crop of dry farming in Nebraska. Record of agricultural experiment farms; Climatic changes; Increase in the use of summer fallow.

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.

Examines runoff and soil moisture in the desert conditions of Arizona. Influence of rainfall on physiographic processes; Facts about the rainfall of the Tucson region in Arizona; Data on the average annual rainfall; Distribution of precipitation; Implications of the irregularity of rainfall in southern Arizona; Occurrence of drought; Determinants to the amount of runoff.

Classifies the literature on climatology. Human climatology or the relationship between climate and man; Botanical or agricultural climatology; Changes of climate; Atlases.

Examines special maps for charting storm movements in the U.S. Fundamentals of aerography; Assessment of the structure of atmosphere in general and sequence of weather changes; Evaluation of the lines of equal pressure.

The article reports on the Becium homblei as a plant with high copper soils in Central Africa. Becium homblei is a plant which endure soil copper concentrations of up to 15,000 ppm and endure soil nickel concentrations of about 5,000 ppm. It is found on areas where soil metals are abundant and soil bases specially calcium are low. It is limited by climatic boundaries such as soil pH, soil metal content, and soil calcium bases. It is also widely distributed in Central Africa due to biotype depletion caused by climatic change.

The article focuses on the utilization of Wilm's method to explain the underlying principles in the collection and statistical treatment of climatic data. It cites that the method is used to determine several chemical elements found in the throughfall data, such as the suspension of bryophyte ground layer in the gauges and approximation of the variance of temperature and humidity data. It also mentions that the changes in the utilization of the method are based on the consideration of the regression line in the data analysis. Further, information on the statistical techniques and methods of computation for the result is also included.

The article examines some problems of mid-Post-glacial ecology and chronology in the area south and east of the English Lake District in England. The post-glacial increase in pine pollen frequencies is discussed. The stratigraphical evidence for changes in water level during mid-Post-glacial times is detailed. Information on the radiocarbon evidence from Lonsdale is presented. A discussion is presented on the relation of pine maximum in Lonsdale to local habitat factors and the climatic implications of the pine maximum in Lonsdale.

The article describes the microclimates of forest and savanna sites in the Olokemeji Forest Reserve in Nigeria. This description is based on rainfall and temperature data from Olokemeji and for other climatic elements, on data from Ibadan. The mean length of dry periods is less than 4 days during the wet season and rises to over 50 days during the dry season. The results show that Olokemeji has a climate typical of it area of the country and of the forest/derived savanna boundary area in west Africa.

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 focuses on a study regarding the plant communities on the northern slopes of the island of Pico in the Azores. It mentions the climatic conditions prevailing in the Azores' islands which are characterized by frequent mists, strong winds and a high rate of rainfall. It states that the Pico island is formed entirely of alkali basalt or olivine, and its northern slopes, the Baldios do Conselho, are less steeper than the slopes in the south and are covered with woodland. The assumed dominance of the Pittosporum undulatum tree has affected the vegetation of the northern slopes of Pico which has further resulted in a complex of vegetation.

The article discusses the study which aims to set on record results of a phenological survey accomplished in conjunction with a local climatic survey in Bath, England during 1945 and 1946. Bath is situated where Avon lessens the gap in the escarpment of the Cotswold Hills and is the center where six valleys developed on the dip slope of the escarpment. Proximity to water, soil type and vegetation cover are factors in local climatology that may locally be dominant and their effects need specific measurement. It is concluded that local variations of temperature are significant in producing local variations of plant growth.

The article outlines the research conducted on the vegetation in Mauritius. Researchers found that the mean annual rainfall over the upland climax forest is of the order of 3175 millimeters and the nearest site where records are available over a long period is at Curepipe Gardens. Another important factor that affect the metabolism of the living organism is the intensity of rainfall from day to day. Knowledge of such distribution would enable them to have a better appraisal of the real wetness or dryness of the site. Discussed are the details of the issue.

The article presents a study of the charcoals obtained from the recent excavations on the Maiden Castle, England and their significance in relation to the vegetation and climatic conditions in prehistoric period. A few specimens of charcoal collected from the site indicated that the wood was partially decayed before carbonizing. The specimens of charcoals were examined from Neolithic, Early Iron Age and Late Iron Age deposits from the site. It was evident that in Neolithic times, the chalk of Dorset was clothed with a closed plant community of woodland. It was observed that composition of plant species were changing slightly in all the three periods and the soil conditions were becoming less favorable for the growth of oak.

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 highlights a report discussing the pleistocene climatic changes and the distribution of life in East Africa. It reports that the present evergreen forest boundaries are generally not natural, noting that they have been reduced by human agency as much as they would have been appreciable drop in rainfall. It discusses the changes that have occurred in the West African forest for a period prior to 400,000 thousand years ago. It also examines the impact of the subsequent dry period in the areas including Elgon, Kilimanjaro, and the highland forms in Southern Tanganyika Territory.

The article offers information on the prevalence of vivipary on the sea shore. It is cited that one of the features of the mangrove forests is the habit of germination of the seeds on the parent trees. It is said that some refer to vivipary as a relic from the past under the uniform climatic conditions, while others regard it as an adaptation to environment, providing the species with a means for dispersal. It is mentioned that viviparous habit could start the growth of roots in the soil, thus, viviparous seeds should establish themselves on a tidal coast.

Describes environmental requirements for germination and flowering, and the pattern of leaf and tiller development in contrasting light and temperature regimes in collections of forage grass. Materials used in the study conducted on the climatic variation of forage grasses; Description of the effect of temperature on percentage and rate of germination; Genetic variation and effect on flowering behavior.