Urban environments are typically host to a high level of biodiversity which is important for the provision of ecosystem services, and for facilitating contact between humans and nature. However, accelerating urbanisation precipitates considerable declines in the number of species which inhabit these environments as a greater number of homes and roads are constructed to accommodate a growing global human population. Domestic gardens afford an important opportunity to combat these declines, owing to their capacity to support a high level of biodiversity and the substantial land area which they cover. However, the fine spatial scale of individual isolated domestic gardens constrains their ability to increase biodiversity at larger spatial scales. Consequently, managing domestic gardens collectively, by conjoining multiple neighbouring domestic gardens and managing them as a single larger habitat, has been proposed as a promising approach to increase biodiversity at these scales. Importantly however, the practical implementation of this approach necessitates neighbouring householders to collaboratively undertake biodiversity favourable garden management and to conjoin their domestic gardens. Crucially, this management is performed by householders discretionarily and can be influenced by demographic, perceptual, environmental, and socio-economic factors. Furthermore, householder attitudes towards conjoining domestic gardens may also influence the practicality of this approach. Therefore, this research explores what impact the extent to which householders undertake biodiversity favourable garden management has on the practicality of the collective management approach and how this is influenced by the aforementioned factors. In addition, it explores how this practicality is influenced by householder attitudes to conjoining domestic gardens. Lastly, it investigates how the collaborative undertaking of biodiversity favourable garden management by neighbouring householders could be encouraged, taking into consideration the constraints associated with current projects which promote such management. A survey was used to explore the prevalence of biodiversity favourable garden management, the influences on this management, and attitudes towards conjoining domestic gardens. This was conducted with an online semi-structured questionnaire which was distributed to householders using the social-networking site, Facebook. In addition, a bio-indicator approach was used to analyse the impact of general domestic garden management on biodiversity and birds were selected as a bio-indicator. Accordingly, respondents to the survey were also required to identify which bird species visit their domestic gardens. Seventeen elite interviews were also conducted with representatives from a range of organisations operating domestic garden projects, participants in such projects, and academics with expertise in domestic garden management, in order to explore the constraints associated with current domestic garden projects. The survey yielded 276 responses and provided support to the practicality of the collective management approach. In particular, it indicated that householders commonly undertake biodiversity favourable garden management, by predominantly providing food for birds and planting vegetation, and 60% of householders are willing to conjoin domestic gardens. However, the survey also highlighted that biodiversity favourable garden management is impeded by a number of factors. These included small domestic gardens, which particularly limit vegetation planting, and can be commonplace in urban environments. In addition, householders commonly nullify the benefits afforded by undertaking this management by covering domestic gardens with hard surface and lawns, which eliminate space for vegetation. Moreover, strong desires to retain ownership and privacy of domestic gardens precipitate the unwillingness of a significant proportion of householders to conjoin domestic gardens. This therefore challenges the practicality of the collective management approach. The results from the elite interviews indicated that householders lack commitment to current domestic garden projects, which are constrained by difficulties acquiring sufficient funding. These issues could also be pertinent to approaches which are developed to encourage the collaborative undertaking of biodiversity favourable garden management, further rendering the collective management approach impractical. The practicality of the collective management approach could be enhanced by modifying the design of new housing in a manner which is favourable to biodiversity and which ensures a minimal domestic garden size. In addition, including domestic gardens in green infrastructure strategies could further enhance this practicality. Furthermore, amending planning policy to regulate the covering of domestic gardens with hard surface and lawns more stringently could reduce the prevalence of these features. Householder commitment to approaches which encourage the collaborative undertaking of biodiversity favourable garden management could be promoted by providing feedback regarding the contribution this makes to increasing biodiversity at large spatial scales. Moreover, greater funding for these approaches could be acquired by also focusing on promoting the provision of ecosystem services. Finally, householder collaboration could be encouraged by accommodating desires for ownership and privatisation of domestic gardens. This could be respectively achieved by permitting flexibility regarding the biodiversity favourable garden management undertaken and separating conjoined domestic gardens with hedgerows.

Thesis (M.A.)--Carleton University, 2003. / Includes bibliographical references (p. 345-358). Also available in electronic format on the Internet.

Cette thèse interroge la place des habitants et de leur jardin dans la gestion de la biodiversité ordinaire, à partir de trois communes situées au cœur de l'agglomération parisienne. Cette question nous conduit à nous intéresser à la sensibilité des habitants-jardiniers au monde vivant, à évaluer le lien entre cette sensibilité et les modes de jardiner et, plus fondamentalement, à envisager le rapport entre cette sensibilité au vivant, ces modes de jardinage et la biodiversité dans les jardins privés. Cette recherche s'appuie sur une base de données constituée d'une enquête par questionnaires (585), enrichie d'un matériau iconographique (110 photos prises par les enquêtés) et de 59 relevés botaniques effectués par des écologues. Nous montrons ainsi que les habitants développent une relation multidimensionnelle avec leur jardin dans laquelle la nature, l'ordre et l'esthétique occupent des places centrales. Au sein de ces rapports pluriels, on identifie comme biophiles des répondants qui justifient leur intérêt pour le jardin par une sensibilité à l'égard du vivant. Les jardins sont ainsi le support d'une relation particulière à la biodiversité caractérisée par des modes de jardinage plus respectueux du vivant. L'indicateur mis en place pour mesurer l'état de la Biodiversité Potentielle dans les Jardins (IBPJ) indique que les jardins forment aussi des espaces de biodiversité, surtout lorsque leurs gestionnaires sont considérés comme biophiles. Dans l'objectif d'améliorer la biodiversité dans les espaces verts privés, nous proposons de dépasser la connexion à la nature souvent préconisée, et d'encourager une connexion au vivant ainsi qu'une nouvelle esthétique du jardin. / This thesis investigates the role of inhabitants and their garden in the management of ordinary biodiversity, based on three towns located within the Greater Paris. This core issue leads us to explore the inhabitants-gardeners' sensitivity towards the living world, to assess the connection between this sensitivity and gardening techniques and, more fundamentally, to consider the link between this sensitivity towards the living, gardening practices and the biodiversity that exists in domestic gardens. This study is based on a database mainly composed of a questionnaire survey (585), enriched by iconographic material (110 pictures taken by the respondents) and by 59 botanical surveys conducted by ecologists. Thus, we demonstrate that inhabitants develop a multidimensional connection with their garden in which nature, order and aesthetics play a central role. Within these plural connections, we identify as biophilic the respondents who justify their interest for the garden by a specific care for the living. Domestic gardens are thus the support to a particular connection to biodiversity distinguished by gardening techniques more considerate of the living. We implement an Index to gauge the state of the Potential Biodiversity in Gardens (IPBG). This index reveals that gardens, areas undertaken by inhabitants-gardeners, are also areas of biodiversity, furthermore when their owners are considered as biophilic. With the aim of improving biodiversity in private green areas, we propose to overstep the connection to nature advocated in several scientific work and by governmental policies, and to encourage a connection to the living and a new aesthetic of the garden.