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Studies the effects of physical disturbance on Arctic vegetation in the Queen Elizabeth Islands. Manipulation studies on Devon Island; Minor effect of removal of vegetation on increased soil heat flux and subsequent thaw; Tolerance of graminoids to periodic removal of above-ground parts; Natural revegetation; Successional trends, potential of artificial rehabilitation and recovery of vegetation from diesel fuel spills.

Vegetational properties of mixed hardwood swamps exposed to different thermal regimes from the release of nuclear reactor effluents were compared on the bases of floristic similarity, importance values of the dominant species, and diversity. Floristic composition was greatly altered by high water temperatures and by increased flooding and silting associated with the discharge of reactor effluents. Although the forest canopy was destroyed, diversity of the herbaceous flora remained high under conditions of thermal loading and post-thermal recovery. Trees comprise 40% of the species present in the undisturbed swamp habitat and less than 10% in the stressed areas. Successional recovery of the swamp following removal of the stress is slow. Such studies are valuable in assessing the responses of natural systems to the introduction and ultimate removal of nuclear reactor effluents. [ABSTRACT FROM AUTHOR]

The maritime cliff-top vegetation of the Lizard and Land's End, West Cornwall, is described in a traditional phytosociological manner. Six new associations are described, together with a number of other noda. The noda are related to environmental factors and the zonataon on the cliffs is found to be determined by the amount of exposure to maritime influence, with further variation due to differences in soil depth and moisture content and to the geology of the underlying rocks. A strongly marked relationship between the percentage of maritime species in a nodum and the sodium-organic ratio is noted. [ABSTRACT FROM AUTHOR]

Discusses the effect of soils on plant ecology. View on the effect of soil as predominantly chemical or purely physical; Impact of the introduction of colloid chemistry on physical and chemical soil characteristics; Consideration of soil as an independent factor that determined subsequent vegetation.

The article focuses on natural vegetation in the Great Plains. The correlation between any single climatic or soil factor and the natural vegetation is often profoundly affected by change in the other factors. Similar distinct differences in the type of vegetation may be caused by any one of a number of factors. In correlating vegetation with conditions of soil or climate this consideration should be kept constantly in mind. A change in either the rainfall, the soil texture, the soil depth, the available soil moisture or the saturation deficit of the air, will be accompanied by a change in vegetation, if the other factors remain constant.

Explores causes of vegetational cycles. Comparability of cycles of vegetation to cycles of erosion; Impact of the climate on the final stage; Characteristics of the original plant formation in any habitat; Succession of plant formation; Division of pioneer formations in moist climates.

Focuses on plant reflectance and color infrared photography in ecology. Reflectivity of plant tissue; Sensitivity of the Kodak Ektachrome Infrared Aero film; Comparison photography of Coleus in color and infrared color; Contribution of infrared color film to the better understanding of variations in the image color of vegetation.

Describes changes in vegetation distribution over the North and Central Rukwa plains of the Rukwa valley in Tanzania. Relation between the changes in the level of lake and changes in vegetation; Distribution of main vegetation associations over Central Rukwa during 1958-59; Range and mean hydrogen ionic concentration of soil collected from different grass species in Central Rukwa during 1959.

The article offers information on Cerrado, the principal vegetation of most of Central Brazil. It is said that the stands of the said vegetation vary in size and density of the trees, from small and scattered to large and dense. The gradient has been codified in terms of basal area of trunks per hectare and divided into four intergrading categories. It is cited that the physiognomic gradient of cerrado vegetation from stands of small, scattered trees through orchard, to well-developed woodland, has been found parallel to soil fertility gradient.

The article presents a study about the grassland vegetation of the Sheffield region. This study investigated the ecology of flowering plants in the Sheffield region in Britain which makes an excellent center for study for its location between highland and lowland areas of the country offering access to the climatic and biological expressions in each zone. Geological strata, altitude and land-use were important factors for this experiment. Diverse and intense biotic pressures were also recorded. Environmental variations and topography also helped in establishing the information needed for this study.

The article reports on the phytosociology of Calluna-Arctostaphylos heaths in Scandinavia and Scotland. Calluna-Arctostaphylos heaths' study provides some insight into the nature of the vegetation and its response to factors of the environment. This plant communities' research were conducted using the techniques of association-analysis and ordination. The latter reveals misclassified stands, while the former suggests a basic division of the data on Hypericum pulchrum into two parts, herb-rich heaths in which it is present and herb-poor heaths where it is absent.

The article reports on the study of the vegetation of Arctostaphyleto-Callunetum in Aberdeenshire, Scotland. It uses a technique wherein misclassification of plants is determined through association analysis to redefine Arctostaphyleto-Callunetum groups for ecological interpretation. It examines vascular plant groups of Arctostaphyleto-Callunetum which were classified into lichen-rich (A), herb-rich (B), intermediate herb-rich (C), and herb-poor (D). It shows that vascular plants' vegetation is related to soil-type. It also demonstrates that bryophytes and lichens of Arctostaphyleto-Calluna recovers after burning.

The article reports on the study of plants seasonal growth of the Olokemeji Forest Reserve in Nigeria. The study focuses on the seasonal changes particularly in the growth of plants on the Olokemeji Forest Reserve. It examines and describes the seasonal changes of plants in terms of climate, microclimate and soil to get information on their seasonal changes in forest and savanna vegetation. It shows that plants' growth period starts on February to March and ends on May or June. It also demonstrates that factors which affect plants' growth are photoperiod, soil moisture, water supply and rainfall.

The article describes the habitat and plant communities in the Egyptian desert. The paper explores the potential variations within desert community types over an extensive area. It examines a summary of an ecological survey of the whole Eastern Desert, extending from the Nile valley of the Red Sea mountains and from latitude 30 degrees north and 22 degrees north. It also discussed the features and ecological relationships of plant communities that form the vegetation of a part of the Eastern Desert of Egypt and outlined assumptions of their definition.

This article presents a study which investigated the plant succession in an irregularly fired grassland area in Doma Peaks Region in Papua. A brief background on the study area, a review of previous related literature and a description of the study's methodology are provided. The effects of irregular burning of vegetation by man are discussed in relation to succession. The study found that some Cyperaceae are important constituents of the succession and exhibit high fire resistance. An illustration of the succession of plant species is provided.

The article reports on one of the biological flora of the British Isles, Teucrium scorodonia L. It is said that the it is commonly found in deciduous woods and wood margins. It is also said that it occurs on both acidic and calcareous soils which are usually well drained. It is less common on wet soil. It is widespread in Britain and is also recorded from all forty of the Irish vice-counties. It is further stated that it is typically found in the less-shaded areas of many kinds of deciduous woodland.

The article reports on one of the biological flora of the British Isles, Schoenus nigricans L. The flora is said to be abundant throughout most of Ireland, but particularly abundant in the west where it is found growing in ombrogenous conditions. Mainly a lowland species in the British Isles. It is said that the habitats of Schoenus are generally waterlogged, with the water table slightly below the surface. It is also said that the plant will not tolerate shading and dies out when the habitat is invaded by bushes.

The article reports on the biological flora of the British Isles. It is said that the L. perenne ssp. anglicum is the sole British representative of the L. perenne group and its relation to the other European members of the group may be summarized as homostylous species and heterostylous species. It is also said that the habit and stem length of L. perenne ssp. anglicum are very variable. It is stated that the habit is phenotypically plastic in so far as it may change considerably during the life of a single plant and is affected by the height and density of the vegetation in which the plant is growing.

The article reports on the ordination techniques which are used in the studies of chalk grassland vegetation. Ordination techniques are classified into vegetational ordinations and environmental ordinations. Vegetational and environmental ordinations give greatest information about the homogeneous community of chalk grassland. Their variations are affected by the dominant effect of the grassland specie namely Zerna erecta. They are also influenced by different environmental factors such as soil property, soil depth, phosphorus and calcium content of the soil.

The article reports on the study of the development of Polygonum affine in the Karakoram Mountains of West Pakistan. It aims to analyze the effect of altitude in the vegetation of Polygonum affine. It is done in the area near the Minapin Glacier and the Tachaferi valley. It finds out that Polygonum affine grew in approximately 3500 meters altitudinal limit of the lateral moraine of Tachaferi valley. It also demonstrates that Polygonum affine can also develop in a glacier which is 200 meters higher than Tachaferi valley even it is separated by 2 km of ice.

The article presents a study on the rapid classification and ordination method and its application to vegetation mapping. An agglomerative method was used as the method of group analysis for the rapid checking of possible misclassifications which are inevitable in a monothetic divisive process. Relative to this, the method is designed for rapid computation even when the survey is large. The method achieves this through the placement of the calculation of N-dimensional space with K-space. On the other hand, the graphic displays of data were gathered directly from an online digital plotter which eliminates tedium associated with vegetation ordination and mapping studies.

The article presents an ecological study of Ysgolion Duon, a mountain cliff in Snowdonia, Wales. The study aims to determine the relation of species distributions on a mountain cliff with environmental factors. Differences in climate between the cliff and surrounding grasslands were studied. Results showed that orloci ordination procedure was able to establish the correlation of species distributions with an environmental gradient from wet eutrophic to dry oligotrophic. The presence of relict species in the flora and the isolation of the cliff from many biotic influences suggests that the vegetation is continuous.

The article examines the factors affecting the distribution of Sphagnum imbricatum in the British Isles. Plants of typical hummock material of S. imbricatum from Ireland and other Sphagna from Wybunbury Moss in Cheshire, England, were used in the experiment. To compare the desiccation resistance of S. imbricatum with other Sphagna, water retaining capacity of the Sphagnum species was tested in both dry and wet conditions. Regression analysis showed that species' water holding capacity alone cannot account for the past abundance and present rarity of the species.

The article discusses the methods of measuring competition in plant population, particularly competition between individual plants. A regular hexagonal pattern of plant arrangement in which the competitive effects between a plant and its six immediate neighbors is considered as a model for competition. Variation of the estimated values of the coefficient is investigated. It was found that there are high errors of the treatment means. Despite the results, the method has shown to be of practical use and could be used as a basic model to build a more complex model for irregularly arranged crops.

The article discusses the results of the survey, conducted from 1958-1965, to calculate the frequency of lime-chlorosis in the natural flora in England. Lime-chlorosis, though a widespread occurrence in England, varies in extent where vegetation on calcareous soils is affected. Results of the survey showed that there is a high frequency of lime-chlorosis on the southern Chalk while there is a minimum effect on Magnesian limestone and Oolitic rocks. Also, species of flowering plants were affected only in the sites wherein there is a high incidence of chlorosis. It was concluded that it is also a seasonal phenomenon that intensifies during the flush growth from May to June.

The article presents a discussion about the existence of Sibbaldia procumbens plant species in Great Britain, Europe, and North America. The article explores the genetic variation of the said species and offers details on its vegetation and plant parts. It is also supplemented with information regarding the geograhical and altitudinal distribution of the Sibbaldia in the arctic regions of Europe, from Iceland to Kola peninsula, its habitats, and climatic and topographic limitations in the localities of Great Britain.

The article discusses the wet-heath community that is associated with three major species namely Molinia caerulea (L.) Moench, Calluna vulgaris (L.) and Erica tetralix L. whose relative proportions change according to local conditions of soil drainage. It is suggested that the three species confined to southern England, occur on the eocene strata of the south-east but ranging over a variety of geological formations from Kent to Somerset. It is inferred that the references are listed describing the geology and topography of the Bramshill Forest area are frequently mentioned in the literature by Rutter, Reynolds and Webster.

The article presents information on a study which investigated the application of association-analysis to phytosociology. It describes and analyzes the application of association-analysis to three major vegetation types: salt-marshes and maritime cliff communities; calcareous fens and related communities; and woodland and scrub. It notes that phytosociology and association-analysis are operating in comparable ways on the same properties of vegetation. It reveals that association-analysis has certain limitations as a model for phytosociology.

The article presents a study which examines the water output of the desert vegetation in the different microhabitats of Wadi Hoff, one of the wadis of the Egypto-Arabian deserts near Helwan, Egypt. The total water output was estimated in the different microhabitats of Wadi Hoff, namely the plateau, the shaded area, and the first and second terraces of the wadi bed. The total water output depends on different factors, mainly the fresh weight of plants, their density, the climatic factors, the floristic composition, and the availability of soil moisture.

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 describes the principal types of vegetation pattern in Horn of Africa. The first pattern is the series of arcs of dense grass and trees parallel to each other, arranged along the contours and separated from each other by bare ground. Vegetation arcs are the commonest type of pattern found in the vegetation. Vegetation arcs are found in areas without any incised drainage pattern, though they may adjoin such areas. They have also discussed the mode of development and the ecological status of vegetation arcs.

The article focuses on a study which examined the vegetation patterns on an unusual Gilgai soil in Riverina, New South Wales. The analytical methods used in the study include, particle size analysis, 15-atmosphere moisture percentage by pressure membrane apparatus and organic carbon by dry combustion. Results revealed that small patches of a richer mesophytic sward occurring among a sparse dryland vegetation lie in gilgai depression. It noted that the difference in the level of depressions and the surrounding ground is only about 2 centimeters (cm). Results of the study suggested that vegetational pattern is due chiefly to differences in soil moisture, that arise through the run-off of rain water from mounds to depressions.

This article focuses on the gross and net production of terrestrial vegetation in Great Britain. It presents a mathematical analysis that indicates photosynthetic rates per day through the use of analog computer methods illustrated in this research. According to the article, this analysis should help integrate the accumulations which should result from measured or hypothetical rates of income and loss. The methods used may also suggest how rapidly a given model ecosystem may restore itself towards a steady state following a specified kind of disturbance.

The article presents a detailed land survey covering the vegetation and soils in Nicaragua, where in it was found that the five zonal vegetation formations were closely related to the length of the dry season. It reports that numerous swamp and riverine communities were detailed, with their environmental relationship, as well as communities on mangrove areas, beach sands, and a large group of salt-meadow communities. It highlights the environmental relations of pine and oak forests, pine savannas, and two other types. It reports on the course of plant succession on various volcanic deposits, with the conclusion being reached in two cases that the rate of succession was largely independent of the effect of vegetation. It also offers an outline of the main hydroseres.

The article focuses on the plant ecology of the coastal areas of northern Eritrea that is about 220 miles long and is about 20 miles in width. It accounts the geomorphology of the area together with the soils. It likewise tries to correlate vegetation type with general levels of salinity using figures given for the percentage sodium chloride in a range of soils. Moreover, it classifies the area on geomorphological grounds and divides it according to soil types and plant communities. The basis for the classifications is also discussed.

The article discusses the vegetation and flower of the islands of Saint Kilda and North Rona in Scotland. It highlights the significant change of the vegetation of Saint Kilda following the departure of the human population in 1930. The change has been manifested by the increase of Calluna vulgaris in the island. Pollen analysis likewise shows that Saint Kilda possesses a partial cover of birch-hazel scrub which reaches its maximum extent at the climatic optimum. Moreover, the dwarf-shrub and Agrostis-Festuca vegetation of Hirta and the Festuca rubra-dominated vegetation of North Rona are probably due to the greater influence of salt spray and mammalian life.

The article focuses on the topographical development of the dune system in South Haven Peninsula of Dorset, England. It discusses the history as well as the physiography of the peninsula that includes current changes of the dune system. It provides the correlation of the changes in soil potential of hydrogen (pH) as well as the organic content with the characteristic plant succession and the historical data. Moreover, it presents a comparison on the succession of other dune systems of comparable age which lie in the greater organic content and higher acidity characteristic.

The article presents a study which examines the plant associes and succession cycles of the sand dune and dune slack vegetation in Newborough Warren, Anglesey, Wales. A brief account of the strand flora and of the flora of the dunes, together with a more detailed account of the plant associes occupying the slacks is presented. The relation of successional trends to the physiographic development of the dune system are discussed. The study found that the ultimate stage of succession found at the present time at Newborough is a dry slack Calluna-Salix heath, which developed under the influence of continued leaching.

The article presents a study which examines the patchiness of vegetation in the semi-arid land of the northern Sudan. Examples of types of patchiness in the distribution of vegetation and their causes are discussed. The study found that the patchiness is chiefly due to the variability of soil moisture conditions which result from the interaction of topography, water, wind, soil characteristics and vegetation itself. It is said that the interaction between wind, water, topography, soil and the vegetation itself plays an important role in the occurrence and distribution of vegetation in the semi-arid regions.

The article reports on Agrostis setacea, a hemicryptophyte and commonly found in the British Isles. The plant's root system is fibrous and developed in the upper 10 centimeters of the soil. The leaf is xeromorphic, with a narrow, V-shaped lamina. The flowers are hermaphrodite and wind pollinated. Flowering is unaffected by the conditions in the different heaths wherein the species is found. There was no record on physiological data. Agrostis setacea's geographical and altitudinal distribution, habitat and phenology are also discussed.

The article offers information on the structure of a grassland community, including the pattern of dactylis glomerata, lolium perenne and trifolium repens. An analysis is presented on the characteristics of Agrostis tenuis, as well as to the physiography of a series of reseeded upland areas. The correlations between four species situated at the grassland indicated the dominant effect of Agrostis in the area. Cases of non-randomness in vegetation are due to slight differences in density of the four species in the area.

The article offers information on the lowland vegetation in the Nigerian Field, after the eruption of Cameroons Mountain in February 1922. Lava flow covers the lowland of the mountain after the eruption, causing forest fires as it moved than the mountain up to the craters to the sea between Isobi and Bibundi. The eruption made extensive damage to the sorrounding vegetation, which must have initiated a varied range of most seres in the mountain region. No vegetation in the earliest stages of the successions appear to have been put on record.

The article presents a study about the studies on grasslands of the Western Ghats in India. This paper focuses on the ecological conditions, topography, climate, soil and vegetation in this area covering the period from June 1953 to December 1955. Various regions were surveyed giving the phytosociological data of the grasslands in Bombay, Khandala, and Lonavla. The methods applied in this experiment are described. Behavioral succession of vegetation were studied related to the biotic factors. Results of the study are discussed in brief.

The article presents a study about the theoretical approach to a study of chalk grassland in England. This paper focuses on the six parts that make up the studies recorded in the past. A brief review of the history in literature of British Chalk Grassland is presented showing the general framework of the previous studies. Different variables in soil formation is detailed and the concepts in vegetation analysis are discussed featuring a functional approach which is a valuable tool in the assessment of various factors affecting the ecosystem balance.

The article looks into the type of eruption and edaphic conditions of three volcanoes in Papua New Guinea. The volcanoes under study are Mt. Lamington, Waiowa Volcano and Mt. Victory, which are all situated within 30 kilometers of the north coast in the Northern division of Papua. A description of the vegetation types ranging from tall tropical rainforest to an open herbaceous community is presented. Correlations with environmental conditions of these vegetation is also drawn. It is observed that some species have survived the eruption of at least one volcano but almost all of the other species were destroyed. These species gradually resurface in blast areas, however, even after 80 years their numbers are below expectations.

The article looks into the development of a number of soil properties in relation to vegetation succession and as a function of age on the morained of the Herbert and Mendenhall glaciers in south-eastern Alaska. The Herbert and Mendenhall systems may be similar, but variations in their properties in relation to the expression of their surface age is observed. These variations are related to the constellations of soil-forming factors. Amongst major soil contents, Nitrogen accumulates at a rate of about 36 pounds/acre/annum or 40 kilograms/hectare/annum. Reaction (pH), bulk density, certain moisture characteristics and properties of the forest floor were also investigated. The main trends in the properties in both systems in relation with time closely resembles those of the Glacier Bay.

The article presents an analysis the mineral composition of the ground vegetations in woodland plantations under the care of the Forestry Commission of Great Britain and adjoining unplanted areas. The ground vegetations collected were analysed for sodium, potassium, calcium, magnesium, manganese, phosphorus, iron, silica and ash. The analysis has found that chemical compositions of the various vegetations differ considerably and are related to the general site conditions and the tree species. It also revealed that these woodland vegetations contain greater percentages of nutrients than the vegetations without any tree cover.

The article offers a description of the vegetation of the Upper Teesdale in England. Information is presented on the topography, geology and climate of Upper Teesdale. It discusses the soils developed on the better drained slopes of moraines on Widdy Bank and Cronkley Pastures. Some of the species comprising the intervening patches of grassland on the Upper Teesdale include Agrostis tenuis, Festuca ovina, Nardus stricta and Dicranum scoparium. Cattle grazing has contributed to the degradation of hay meadows in the Upper Teesdale.

The article presents a study which examined the nature and status of vegetation in Woodwalton and Holme fens in Huntingdonshire, England. Information is presented on topography and drainage at Woodwalton fen. It has found that there has been some development of acid bog in Woodwalton fen based on evidence available from peat stratigraphy and from historical documents. It relates the complete absence of rare fen species at Woodwalton. Some species like Pedicularis sylvatica and Carex echinata have reached the verge of extinction due to considerable drying out.