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This thesis investigated graph theoretic analysis of connectivity and habitat availability for landscape scale management of Triturus cristatus, the Great Crested Newt. The ecological foundations of wider landscape management concepts and knowledge base on T. cristatus' habitat requirements, dispersal and migration were explored. Species presence, and aquatic and terrestrial habitat on the Cholmondeley Estate, Malpas, Cheshire, UK was mapped and land cover characterized for suitability and traversibility by T. cristatus. Habitat area available and accessible from ponds were identified. Analysis and modelling of pondscape connectivity using Probability of Connectivity (PC) and related indices, was carried out using Euclidean and Cost Weighted Distance and pond clustering at ecologically relevant scales was examined. Association or correlation of presence with proximity to breeding ponds, pond cluster size, proximity and available quantity of terrestrial habitat, proximity to roads and moving water, and connectivity of breeding ponds were examined at Cost Weighted and Euclidean distances. Connectivity, (PC index), pond count in clusters at 250 and 500m thresholds of connectivity, and proximity to core habitat (broad leaved woodland and rough grassland) using Cost Weighted distances were positively associated with breeding presence. Road proximity and density, proximity of core habitat at Euclidean distances and mean inter-pond distance were not significantly associated with breeding presence. Proximity to moving water was negatively associated with breeding presence. Resistance to movement of various land cover types has important implications for habitat availability and connectivity, , / and important questions are raised in terms of "rule of thumb" guidelines for estimation of connectivity between pond populations and habitat availability around breeding ponds. Graph analysis was used to identify priority areas for maintenance of landscape level connectivity, and enhancement of habitat connectivity and availability on the local population scale, with prioritization of pond creation/protection sites against their contribution to connectivity and habitat I availability, examining various scenarios.

Quantitative Structure-Activity relationship (QSAR) attempt statistically to relate the physico-chemical properties of a molecule to its biological activity. A QSAR analysis was performed on the toxicities of up to 75 organic chemicals to two aquatic species, Photobacterium phospherum (known as the Microtox test), and the fathead minnow. To model the toxicities 49 physico-chemical and structural parameters were produced including measures of hydrophobicity, molecular size and electronic effects from techniques such as computational chemistry and the use of molecular connectivity indices. These were reduced to a statistically more manageable number by cluster analysis, principal component analysis, factor analysis, and canonical correlation analysis. The de-correlated data were then used to form relationships with the toxicities. All the techniques were validated using a testing set. Some good predictions of toxicity came from regression analysis of the original de-correlated variables. Although successful in simplifying the complex data matrix, principal component analysis, factor analysis, and canonical content analysis were disappointing as predictors of toxicity. The performance of each of the statistical techniques is discussed. The inter-species relationships of toxicity between four Commonly utilised aquatic endpoints, fathead minnow 96 hour IC50, Microtox 5 minute EC50, Daphnia magna 48 hour IC50, and Tetrahymena pyriformis 60 hour IG50, were investigated. Good relationships was found between the fathead minnow and both T. pyriformis and D. magna toxicities indicating that these species could be used to model fish toxicity. The outliers from individual relationships were assessed in order to elucidate if any molecular features may be causing greater relative toxicity in one species as compared to another. It is concluded that in addition to the intrinsic differences between species, the greater length of the test time for any species may result in increases bioaccumulation, metabolism, and detoxification of certain chemical classes. The relationships involving fish toxicity were moderately improved by the addition of a hydrophobic parameter.

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The afforestation of upland areas in the UK has been the largest rural land use change this century. As a consequence of afforestation the bed load yields of upland catchments have been shown to increase substantially. The upland catchment bed load is transported downstream, through the transfer zone to the lowland reaches where it may enter storage in barforms, cause flow diversion and cause channel instability. This study investigates the Afon Trannon, a river in mid-Wales whose upland catchment was afforested between 1948 and 1978 and whose lowland channel is currently unstable. Historical rates of channel change in the lowland channel have been quantified using aerial photogrammetry in ERDAS Imagine GIS. Channel instability is shown to increase significantly between 1963 and 1976, some 15 years after upland catchment afforestation. However, upland catchment bed load yields are shown to be of low magnitude (up to an estimated maximum of6.35 t km-2 yr") and incapable of producing the high medium-term lowland channel change rates observed (up to 1.88 m yr" between 1963 and 1976). Contemporary channel DTMs constructed from field survey data have allowed the construction of a contemporary lowland channel sediment budget. Local inputs of bed load from composite bank erosion are shown to dominate in the budget and reaches of maximum instability are shown to correspond with the location of these composite banks. Additionally. flood magnitude and frequency are shown to have increased since 1988 from a maximum stage of 1.50 m between 1969 and 1988 to a maximum stage of2.23 m between 1989 and 2000. A conceptual model is presented in which the medium-term instability of the lowland Afon Trannon is suggested to be triggered by local lowland bed aggradation as a result of elevated upland catchment bed load yields and a risk assessment diagram provides advice to river engineers and fluvial geomorphologists interested in assessing the potential stability of lowland rivers whose upland catchments have been afforested.

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Made available in DSpace on 2018-08-24T22:53:22Z (GMT). No. of bitstreams: 1 tese_5983_.pdf: 1406622 bytes, checksum: f33eb5980f6acd48cb2b31f7820b6961 (MD5) Previous issue date: 2012-08-24 / O gerenciamento de resíduos sólidos é um desafio enfrentado pela sociedade atualmente. Existem vários fatores que impactam esse problema, dentre eles, o aumento da quantidade de resíduos gerados. Esse trabalho detalha as principais formas de destinação e o consumo das embalagens de cimento pós-consumo atualmente empregados na Grande Vitória; descreve o processo de logística reversa da sacaria de cimento após utilização na fábrica de cimento estudada; e estuda as alternativas viáveis para a destinação ambientalmente adequada desse resíduo. Para isso foi feito um levantamento de dados em obras da construção civil, uma avaliação na única fábrica que pratica a logística reversa da sacaria de cimento no estado do Espírito Santo e o levantamento de possíveis alternativas de disposição adequada das embalagens retornadas no estado. Foi constatado que existem diversas formas de destinação dos resíduos da construção civil, como disposição em terrenos da prefeitura, aterramento e recolhimento das embalagens pós-consumo. A prática da logística reversa na fábrica de cimento apresenta muitas limitações, como a presença do cimento que impede a reciclagem ou reutilização do mesmo, tornando sua disposição um procedimento custoso para a fábrica de cimento. A falta de planejamento que vise o controle da quantidade de embalagens que retornam, a ausência de um processo de conscientização de todos os participantes, entre outros fatores, impedem o sucesso do processo reverso. Assim, são necessários investimentos tanto no desenvolvimento do fluxo reverso nos setores participantes como em tecnologias para o retorno dessas embalagens em processos produtivos, visando o retorno ambiental e social da implantação da logística reversa.

There is a growing global urban appetite for fresh fruit and vegetables, particularly fruit. There is a further recognised need for agri-food systems that support human health, ecological integrity and social justice (Morgan and Sonnino 2010). This thesis explores the current possibilities and challenges of regenerative agri-food systems through the case of the urban apple. With the lens of political ecology, the thesis presents a relational interpretation of the spaces, natures and relations of the urban apple through considering the practices and the guiding logic of the corporate and agro-ecological urban apple in Hackney, London. The methodological framework, informed by relational geographies, supports a situated and place-based understanding of the corporate and agro-ecological logics through attending to practices in place. The thesis draws upon a number of semi-structured interviews and participant-observation with representatives involved in the production, distribution and trading of the urban apple. As the case of Growing Communities demonstrates, citizens can be supported in practicing more healthy, ecological and just ways of growing, trading and consuming food through agro-ecological communities of practice. Currently, such communities remain politically marginalised, particularly at national government levels. A political framework that fosters physical, economic and political space for regenerative agri-food practices and systems is considered key. The city-region is recognised as a ‘space of possibility’ and ‘space of action’ (Gibson-Graham and Roelvink 2011) in the scaling-out regenerative agri-food practices and systems. This needs to be supported by multi-scalar, cross-sectoral, participatory and co-productive processes (Jennings et al. 2015; Moragues-Faus and Morgan 2015; Jégou and Bonneau 2014), prioritising space for community-led, place-based practice.

The potential impacts of climate change and environmental variability are already evident in most parts of the world, which is witnessing increasing temperature rates and prolonged flood or drought conditions that affect agriculture activities and nature-dependent livelihoods. This study was conducted in Mwanga District in the Kilimanjaro region of Tanzania to assess the nature and impacts of climate change and environmental variability on agriculture-dependent livelihoods and the adaptation strategies adopted by small-scale rural farmers. To attain its objective, the study employed a mixed methods approach in which both qualitative and quantitative techniques were used. The study shows that farmers are highly aware of their local environment and are conscious of the ways environmental changes affect their livelihoods. Farmers perceived that changes in climatic variables such as rainfall and temperature had occurred in their area over the period of three decades, and associated these changes with climate change and environmental variability. Farmers’ perceptions were confirmed by the evidence from rainfall and temperature data obtained from local and national weather stations, which showed that temperature and rainfall in the study area had become more variable over the past three decades. Farmers’ knowledge and perceptions of climate change vary depending on the location, age and gender of the respondents. The findings show that the farmers have limited understanding of the causes of climatic conditions and environmental variability, as some respondents associated climate change and environmental variability with social, cultural and religious factors. This study suggests that, despite the changing climatic conditions and environmental variability, farmers have developed and implemented a number of agriculture adaptation strategies that enable them to reduce their vulnerability to the changing conditions. The findings show that agriculture adaptation strategies employ both planned and autonomous adaptation strategies. However, the study shows that increasing drought conditions, rainfall variability, declining soil fertility and use of cheap farming technology are among the challenges that limit effective implementation of agriculture adaptation strategies. This study recommends further research on the varieties of drought-resilient crops, the development of small-scale irrigation schemes to reduce dependence on rain-fed agriculture, and the improvement of crop production in a given plot of land. In respect of the development of adaptation strategies, the study recommends the involvement of the local farmers and consideration of their knowledge and experience in the farming activities as well as the conditions of their local environment. Thus, the findings of this study may be helpful at various levels of decision making with regard to the development of climate change and environmental variability policies and strategies towards reducing farmers’ vulnerability to current and expected future changes.