<p>Environmental health effects from chemicals are an example of risks associated with modern, industrialized, technologically advanced, capitalist society. In Canada approximately 23,000 substances have been in commercial use despite never being assessed for their risks to human health and the environment. The assessment, management and regulation of environmental health risks from “existing” chemical substances can be viewed as an emerging and contested domain of governance whereby an increasing number of diverse stakeholders are seeking to shape its constituent actors, rule systems, knowledge inputs, and orientation. Using a multi-method case-study of Canada’s Chemicals Management Plan, this thesis examines how governance and decision-making rationales, knowledge inputs, influence, and authority become constructed, negotiated and (de)legitimized in practice, and the role and significance of “space” in these processes. Sources of data include scientific, policy and legal documents, participant observation and key informant interviews. Findings reveal that stakeholders divergently interpret evidence and exploit scientific uncertainties using various tactics that (de)legitimize particular claims and policy prescriptions to favour their interests. This has significant implications for how “precaution” and “weight-of-evidence” are operationalized. The concepts of “scale-frames” and “boundary-work” reveal how stakeholders construct and spatially bound political and epistemic legitimacy and authority through contested definitions and rationales of accessibility, inclusion and exclusion. To gain the influence and legitimacy that is needed for effectively shaping environmental health policy stakeholders must (re)define the jurisdictional <em>and </em>epistemic spaces in which knowledge, evidence and rationales are created and institutionalized. Bringing contested modes of subject-making around expertise and technical capacity to the fore assists in explaining why particular forms of knowledge production and interpretations of evidence are adopted while others are downplayed. This in turn perpetuates particular kinds of risk assessment and management tools and approaches that benefit some and marginalize others. Prevailing “governmentalities” are supported by, and mutually reinforce, broader neo-liberal political-economic ideals and interests.</p> / Doctor of Philosophy (PhD)

Chemical pollution has become an environmental and human health concern. Small and medium-sized enterprises are becoming the focus of environmental researchers, as they have been found to collectively contribute a significant amount of the pollution due to improperly managed chemicals. This case study of Nova Scotia small and medium-sized enterprises aimed to collect baseline information regarding environmental and chemical management including what positive practices were in place, what areas required more assistance, what information is being requested and who should be the focus of information programs. Results indicated that there is significant room for improvement in both the environmental and chemical management practices of small and medium-sized enterprises, even though participants indicated they were employing responsible practices. Participants were however, able to provide multiple suggestions regarding information they require in order to improve their business operations and environmental performance, thereby indicating they are aware improvements are needed.

Resumo: A agricultura de precisão implica a análise da variabilidade espacial dos fatores de produção e a aplicação dos insumos de forma localizada e em doses precisas. O presente trabalho teve por objetivo analisar a influência do relevo na variabilidade espacial dos atributos químicos e mineralógicos para aplicação de insumos em taxa variável. Duas parcelas de um hectare foram delimitadas em área côncava e convexa. Foram retiradas 121 amostras em cada área. Os teores de P disponível apresentaram-se diferenciados nas duas áreas estudadas, sendo que os menores valores médios de P se encontram na área convexa na qual estão presentes os maiores teores de gibsita. A formação dos minerais da fração argila é condicionada pelas variações do relevo, sendo que a área convexa apresentou ambiente mais favorável à formação da gibsita do que a área côncava, demonstrando que o relevo pode ser utilizado para a definição de limites de área mais homogênea. A gibsita foi o fator determinante para a maior capacidade de adsorção máxima de P e a menor disponibilidade de fósforo na área convexa. O uso da técnica de geoestatística possibilitou a precisa descrição das propriedades do solo. / Abstract: Precision agriculture implies on the analysis of the spatial variability of the production factors and the application of inputs in a localized way and on precise doses. The present work aimed to analyze the influence of the relief on the spatial variability of the chemical and mineralogical attributes for the application of inputs in variable rates. Two parcels of one hectare were bounded in concave and convex area. 121 samples were taken from each area. The levels of available P have shown to be different on the two studied areas, being the lowest mean values of P on the convex area, where the highest levels of gibbsite are present. The formation of the minerals from the clay fraction is conditioned by the relief variations, being that the convex area has presented a more favorable environment for the formation of gibbsite than the concave area, showing that relief may be used for the definition of limits in more homogenous areas. Gibbsite was the determinant factor for the higher capacity of P maximum adsorption and lower availability of phosphorous on the convex area. The use of the geostatistics technique has made possible the precise description of the soil properties. / Orientador: José Marques Júnior / Coorientador: Gener Tadeu Pereira / Banca: Luis Reynaldo Ferracciú Alleoni / Banca: Marcilio Vieira Martins Filho / Mestre

Made available in DSpace on 2014-06-11T19:28:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-28Bitstream added on 2014-06-13T20:28:03Z : No. of bitstreams: 1 barbieri_dm_me_jabo.pdf: 1564707 bytes, checksum: a8664218c7a3889aee0ba6b464711e70 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A agricultura de precisão implica a análise da variabilidade espacial dos fatores de produção e a aplicação dos insumos de forma localizada e em doses precisas. O presente trabalho teve por objetivo analisar a influência do relevo na variabilidade espacial dos atributos químicos e mineralógicos para aplicação de insumos em taxa variável. Duas parcelas de um hectare foram delimitadas em área côncava e convexa. Foram retiradas 121 amostras em cada área. Os teores de P disponível apresentaram-se diferenciados nas duas áreas estudadas, sendo que os menores valores médios de P se encontram na área convexa na qual estão presentes os maiores teores de gibsita. A formação dos minerais da fração argila é condicionada pelas variações do relevo, sendo que a área convexa apresentou ambiente mais favorável à formação da gibsita do que a área côncava, demonstrando que o relevo pode ser utilizado para a definição de limites de área mais homogênea. A gibsita foi o fator determinante para a maior capacidade de adsorção máxima de P e a menor disponibilidade de fósforo na área convexa. O uso da técnica de geoestatística possibilitou a precisa descrição das propriedades do solo. / Precision agriculture implies on the analysis of the spatial variability of the production factors and the application of inputs in a localized way and on precise doses. The present work aimed to analyze the influence of the relief on the spatial variability of the chemical and mineralogical attributes for the application of inputs in variable rates. Two parcels of one hectare were bounded in concave and convex area. 121 samples were taken from each area. The levels of available P have shown to be different on the two studied areas, being the lowest mean values of P on the convex area, where the highest levels of gibbsite are present. The formation of the minerals from the clay fraction is conditioned by the relief variations, being that the convex area has presented a more favorable environment for the formation of gibbsite than the concave area, showing that relief may be used for the definition of limits in more homogenous areas. Gibbsite was the determinant factor for the higher capacity of P maximum adsorption and lower availability of phosphorous on the convex area. The use of the geostatistics technique has made possible the precise description of the soil properties.

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