The study traces the history and development of Loe Pool, a 50 hectare freshwater coastal lake near Helston, Cornwall. using a wide variety of palaeolimnological and associated research techniques. The principle upon which such research is based is that there is an intimate relationship between the history of a catchment and the lake into which it drains. In addition, the history of the shingle bar which now isolates Loe Pool from the sea is explored, as this has also had a significant bearing on the lake's physical and ecological development. The study uses a combination of lines of evidence to interpret the development of the lake-catchment system. Palaeolimnological techniques. employed include the examination of the physical nature of the lake sediments themselves, and chemical and biological analyses, in particular for sub-fossil diatoms. These are used to establish both a chronology of sediment deposition, and also a detailed history of the principal ecological changes experienced by the Pool. In addition, a considerable amount of historical documentary and cartographic 'material is incorporated in the study, in order to provide corroborative evidence of the major events that have taken place in the history of the lake and catchment. The results highlight the main influences on the lake, and in particular, those of the last two hundred years. Marine incursions dominated the lake's history up until the late 19th century, when both natural overspill of lake water and the customary practise by local residents of 'breaching the bar' ceased. Tin mining within the catchment has also had a major impact on the lake and has given rise to several periods of very rapid sediment accumulation, the most significant of which took place in the 1930's and 1930's. Following the cessation, in 1939, of all mining activity within the catchment, the discharge of treated sewage effluent, which had begun in 1930, became the dominant influence upon the lake's ecology. It is hoped that such an historical background will allow a more sympathetic management of the lake in future years.

Published also as Thesis (Ph. D.)--University of Illinois, 1929. / Cover title. "Contribution from the Zoological laboratory of the University of Illinois no. 365." Reprinted from Ecology, vol. XI, no. 2, April, 1930. "Literature cited": p. 426-431.

Published also as Thesis (Ph. D.)--University of Illinois, 1929. / Cover title. "Contribution from the Zoological laboratory of the University of Illinois no. 365." Reprinted from Ecology, vol. XI, no. 2, April, 1930. "Literature cited": p. 426-431.

Thesis (diplôme d'archiviste paléographe)--École nationale des chartes, Paris, 2002 and Thesis (Ph. D.)--Université Paris IV Sorbonne, 2004. / Includes bibliographical references (p. [519]-522) and indexes.

Thesis (diplôme d'archiviste paléographe)--École nationale des chartes, Paris, 2002 and Thesis (Ph.D.)--Université Paris IV Sorbonne, 2004. / Includes bibliographical references (p. [519]-522) and indexes.

No description available.

This thesis investigates past structure and dynamics of native Caledonian pine woodland, representing part of the western fringes of the northern European boreal woodlands. The biogeographical extent and Holocene history of the Scottish pine woods are well studied, yet questions remain at finer scales. This thesis is concerned with two factors over the recent Holocene oceanic period; (i) the long-term ecology within the woods; the spatio-temporal dynamics, the canopy structure, and community composition and continuity; and (ii) the former extent of the woods, especially the temporal pattern of the inferred easterly contraction in woodland over recent history. The importance of these factors - to ecologists, challenged with understanding the theories of equilibrium and non-equilibrium processes in long-lived woodland communities - and to conservation managers - challenged, by policy directives, with implementing the restoration and expansion of native woodlands - is discussed. Equally the identification and quantification of ecological detail over ecologically relevant temporal and spatial scales is an important challenge for palaeoecology. The thesis therefore applies fine spatial resolution pollen analyses over a network of sites, within, and at the western edge of, the extant woodland zone in east Glen Affric. Correlation between these individual site histories develops a detailed view of the grain and extent of woodland within the landscape, previously missing from western pine woods. Careful attention is paid to the interpretive potential and limitations of fine resolution palaeoecology; especially with regard (i) to techniques that can identify and spatially quantify stand-scale structure and community composition via reference to modern analogues; and (ii) to defining chronologies and elucidating rates and patterns of temporal change. The opportunities and limitations of the technique are explored and discussed, to ensure an understanding of the rigour and potential of the palaeoecological contribution to ecological research and to provide an evidence base for conservation. The application of 210Pb dating using the CRS and CIC models is explored. The CRS model is confirmed as suitable for peat deposits, but its use may mask fluctuations in peat sedimentation rate, which may be illustrated by the CIC model. The value of multiple 14C assays for each core and a need for a new approach to chronologies for application to fine-scale palaeecological studies is discussed. The relevant source area around the small basins in this semi-open pinewood is tentatively confirmed at 20 m from the pollen source. Tentative pollen productivity estimates for five key taxa in this ecosystem are presented. The temporal stability of native woodland in Glen Affric is confirmed to the eastern part of the extant woodland zone; but challenged to the west, where the open and semi-open landscape has a long history. Woodland diversity decreased over the last c. 200 years, and past woodland also shows a greater ground flora diversity. The western extent of the Caledonian woodland in this landscape may have changed little in the last c. 4000 years. Fluctuations, some clearly cyclical, in heath, and in woodland, communities are identified in the pollen record. The former may be aligned to changes in grazing regime or climatic shifts; and the latter to autochthonous shifts important in the maintenance of suitable edaphic conditions for the continuity of woodland. Former woodland is confirmed as likely to have been open in structure and mixed in tree species composition. The results presented here suggest that some caution should be applied to use of the term Caledonian, or native ‘pine’ forest: ‘Caledonian forest’ may better reflect the heterogeneity of past forests, particularly the importance, and persistence, of birch. The implications for conservation management and restoration are discussed. It may be difficult to establish a sustainable woodland to the west of the extant stands, and any pine woodland here may need to be mixed with stands of broadleaved trees to maintain or restore soil structure and ecological function. The landscape to the west may have been open for several thousands of years, and consideration of this is required when managing for the future to prevent loss of biodiversity.

O objetivo desta pesquisa é apresentar um estudo, sob o ponto de vista histórico, sobre as ideias do botânico e taxonomista americano Henry Allan Gleason (1882-1975) referentes ao conceito individualístico de associação de plantas. Nas décadas iniciais do século XX, as ideias do ecólogo americano Frederic Edward Clements (1874-1945) sobre a dinâmica da vegetação e sobre sucessão ecológica eram prevalecentes. Porém, a discordância dessas ideias parece ter levado Gleason a propor inicialmente o conceito individualístico da ecologia e, posteriormente, o conceito individualístico de associação de plantas. O desenvolvimento do conceito individualístico proposto por Gleason pode ser analisado, principalmente, por meio de suas obras dos anos de 1917, 1926 e 1939. Além dessas, nas quais Gleason refere-se especificamente ao conceito individualístico, outras obras estão sendo consideradas, como seu artigo publicado no ano de 1909, no qual discutiu sobre algumas questões fitogeográficas e ecológicas que influenciariam a distribuição de pradarias e florestas; seu artigo publicado em 1910, no qual apresentou o primeiro indício da sua visão individualística, e seu artigo publicado em 1927, no qual ele discorreu sobre os processos de sucessão em diferentes locais. A partir da análise de obras originais de Gleason e Clements, bem como mediante os relatos das fontes secundárias considerando o contexto da época, procurar-se-á evidências que mostrem o entendimento de Gleason sobre os estudos ecológicos e suas contribuições ao arcabouço teórico da Ecologia. / The objective of this research was to study, from a historical perspective on the ideas of botanist and taxonomist American Henry Allan Gleason (1882-1975) for the individualistic concept of plant association. In the early decades of the twentieth century, the American ecologist ideas Frederic Clements (1874-1945) on the dynamics of vegetation and on ecological succession were prevalent. However, the disagreement of those ideas seems to have taken Gleason initially proposing the individualistic concept of ecology and subsequently the individualistic concept of plant association. The development of the individualistic concept proposed by Gleason can be analyzed primarily through his works of the years 1917, 1926 and 1939. In addition to these, in which Gleason refers specifically to the individualistic concept, other projects are being considered, as its Article published in 1909, which discussed some phytogeographic and ecological issues that influence the distribution of grasslands and forests; Article published in 1910, which presented the first evidence of its individualistic vision, and his article published in 1927 in which he talked about the succession processes in different locations. From the analysis of original works of Gleason and Clements, as well as by reports of secondary sources considering the context of the time, it will be sought evidence to show understanding of Gleason on the ecological studies and their contributions to the theoretical framework of Ecology.

A constituição da idéia de meio ambiente urbano é aqui avaliada sob a perspectiva das concepções que, historicamente, tentam enquadrar as cidades em categorias biológicas, tais como “corpo", “organismo" e, contemporaneamente, “(ecos)sistema". Essa tendência de naturalização ou biologização das cidades é característica do pensamento social pelo menos desde o século XIX: seus antecedentes são certamente ainda mais remotos, mas as origens de seus aspectos contemporâneos mais característicos podem ser encontradas em meados do século XVIII. Este trabalho visa resgatar alguns dos aspectos mais importantes dessa história, pondo em questão a validade de tais categorias para compreensão e intervenção sobre a cidade real. Para tanto, o trabalho dedica-se a investigar os sentidos atribuídos à idéia de natureza e a conseqüente apreciação da agência humana, e da cidade em particular, feita por essas concepções. Qualifica-se o processo de naturalização como parte de um esforço mais amplo de negação ou disciplinamento do artifício (a ação humana) e do acaso (a ausência de causalidade ou finalidade) na constituição do mundo – negação esta que resultaria em um conjunto de categorias de estase para interpretação da realidade e, afinal, em apologia do status quo. Desde o sanitarismo do século XIX até a Ecologia do pós-2ª. Guerra Mundial, passando pelo caso particularmente controverso da Eugenia, as tentativas de biologização das cidades, tanto por parte das ciências biomédicas quanto do próprio Urbanismo em constituição, apontam para uma tendência de dominação pelo conhecimento técnico que permeia de forma recorrente a modernidade capitalista. Nela, tanto a “natureza" quanto os seres humanos comuns (não “escolhidos") são concebidos como recursos naturalmente passivos e sujeitados, incapazes de criar, cabendo-lhes apenas o papel de “resistir" ou “reagir", ou ainda serem “protegidos". Esse “paradigma da dominação" é que requer reconhecimento e enfrentamento, indicando a necessidade de politizar e historicizar a questão ambiental, principalmente em relação às cidades. / In this dissertation the formulation of a concept of ‘urban environment’ is based on the perspective of ideas which have historically attempted to understand cites in biological terms, such as “body", “organism" or more recently “eco-system". This tendency to ‘naturalize’ or conceive cities in biological terms has been a characteristic of social thinking especially since the 19th century. The roots of this tendency are certainly much more remote but this perspective did receive an important impulse from the mid-18th century ideas of the enlightenment. The following dissertation attempts to recuperate some of the more important aspects of this history, questioning the validity of this tendency for the comprehension of and intervention in contemporary cities. Because of this, the study is dedicated to the investigation of the various understandings attributed to the idea of nature with their peculiar appreciation of human agency and of the city. Qualifying this process of naturalization is seen as part of a wider preoccupation of negating or disciplining notions of ‘the artificial’ seen as the product of human agency, and of ‘chance’ when seen as the absence of causality or finality, in our constitution and interpretation of the world which in very many cases becomes an apology in favor of the ‘status quo’. Since the influence of ideas based on hygiene and sanitary conditions in the 19th century and the Darwinian twin conceptions of ecology and the controversial idea of eugenics (up to the mid 20th century) urban history has accepted the expanding role of biological metaphors. This has been expressive both in the biomedical sciences and also in the evolving science of urbanism. In many senses this has been part of the wider tendency towards domination by technical knowledge which is a recurrent feature of capitalist modernity. In this interpretation the dissertation attempts to show that ‘nature’, just as much as ordinary common people are conceived as resources, ‘naturally’ passive, without any capacity to create and with a mere capacity to ‘resist’, to ‘react’ or to ‘conform’ to their eventual ‘protection’. It is this academic paradigm of domination which needs to be recognized and confronted. In this sense the dissertation is an attempt to historically politicize the environmental question, especially in its urban dimension.

O objetivo desta pesquisa é apresentar um estudo, sob o ponto de vista histórico, sobre as ideias do botânico e taxonomista americano Henry Allan Gleason (1882-1975) referentes ao conceito individualístico de associação de plantas. Nas décadas iniciais do século XX, as ideias do ecólogo americano Frederic Edward Clements (1874-1945) sobre a dinâmica da vegetação e sobre sucessão ecológica eram prevalecentes. Porém, a discordância dessas ideias parece ter levado Gleason a propor inicialmente o conceito individualístico da ecologia e, posteriormente, o conceito individualístico de associação de plantas. O desenvolvimento do conceito individualístico proposto por Gleason pode ser analisado, principalmente, por meio de suas obras dos anos de 1917, 1926 e 1939. Além dessas, nas quais Gleason refere-se especificamente ao conceito individualístico, outras obras estão sendo consideradas, como seu artigo publicado no ano de 1909, no qual discutiu sobre algumas questões fitogeográficas e ecológicas que influenciariam a distribuição de pradarias e florestas; seu artigo publicado em 1910, no qual apresentou o primeiro indício da sua visão individualística, e seu artigo publicado em 1927, no qual ele discorreu sobre os processos de sucessão em diferentes locais. A partir da análise de obras originais de Gleason e Clements, bem como mediante os relatos das fontes secundárias considerando o contexto da época, procurar-se-á evidências que mostrem o entendimento de Gleason sobre os estudos ecológicos e suas contribuições ao arcabouço teórico da Ecologia. / The objective of this research was to study, from a historical perspective on the ideas of botanist and taxonomist American Henry Allan Gleason (1882-1975) for the individualistic concept of plant association. In the early decades of the twentieth century, the American ecologist ideas Frederic Clements (1874-1945) on the dynamics of vegetation and on ecological succession were prevalent. However, the disagreement of those ideas seems to have taken Gleason initially proposing the individualistic concept of ecology and subsequently the individualistic concept of plant association. The development of the individualistic concept proposed by Gleason can be analyzed primarily through his works of the years 1917, 1926 and 1939. In addition to these, in which Gleason refers specifically to the individualistic concept, other projects are being considered, as its Article published in 1909, which discussed some phytogeographic and ecological issues that influence the distribution of grasslands and forests; Article published in 1910, which presented the first evidence of its individualistic vision, and his article published in 1927 in which he talked about the succession processes in different locations. From the analysis of original works of Gleason and Clements, as well as by reports of secondary sources considering the context of the time, it will be sought evidence to show understanding of Gleason on the ecological studies and their contributions to the theoretical framework of Ecology.