Amenity trees provide physical, social and economic benefits to people sharing their environment. To maintain the benefits that many people have come to expect of trees in their urban landscapes, a viable and dynamic tree population is required. To this end it is necessary to plant new trees or replace existing trees when they require removal. The challenge when replacing mature trees is not simply the process of planting a tree when one is removed, but of the continual replacement of the entire tree population in a planned and managed fashion. In urban landscapes this is not a natural process, and human intervention is required.

Amenity trees provide physical, social and economic benefits to people sharing their environment. To maintain the benefits that many people have come to expect of trees in their urban landscapes, a viable and dynamic tree population is required. To this end it is necessary to plant new trees or replace existing trees when they require removal. The challenge when replacing mature trees is not simply the process of planting a tree when one is removed, but of the continual replacement of the entire tree population in a planned and managed fashion. In urban landscapes this is not a natural process, and human intervention is required.

Thesis (Ph.D.)--University of Melbourne, Institute of Land and Food Resources, 2005. / Typescript (photocopy). Includes bibliographical references (p. 382-410).

Thesis (M.S.)--Washington State University, May 2008. / Includes bibliographical references (p. 56-62).

Thesis (Ph. D.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 306-325).

The complexity of urban areas within the mosaic of private and public vegetation has led communities to enact regulations to manage numerous benefits of urban vegetation. As urban populations continue to increase, regulations for governing vegetation becomes increasingly common. This study examined the variation in trends, structure, language, clauses, and provisions of vegetation ordinances within communities across the Southern United States. Qualitative content analysis using NVivo computer software was used for analyzing ordinances collected from Municode. Several discrepancies and similarities were explored in ordinance structure and content, along with problems such as lack of effective ordinance components (enforcement and severability provisions), unclear goals, unclear provisions, inadequate information, duplications, section contradictions, and misspellings. Findings will guide urban foresters, arborists, planners, and elected officials while developing new codes and suggest a need to draft better ordinances and revise problematic ones to increase positive impacts on the community green infrastructure.

by Chan Wai-yi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 142-154). / Abstract --- p.i / Acknowledgements --- p.iii / List of Tables --- p.iv / List of Figures --- p.vi / List of Plates --- p.vii / List of Appendices --- p.viii / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- Urban environment and urban trees in Hong Kong --- p.1 / Chapter 1.2 --- Conceptual framework of the study --- p.3 / Chapter 1.3 --- Objectives of the study --- p.12 / Chapter 1.4 --- Scope and significance of the study --- p.12 / Chapter 1.5 --- Organization of the thesis --- p.14 / Chapter CHAPTER 2 --- STUDY AREA / Chapter 2.1 --- Location --- p.15 / Chapter 2.2 --- Climate --- p.19 / Chapter 2.3 --- Planter --- p.21 / Chapter 2.4 --- Soils --- p.22 / Chapter 2.5 --- Management --- p.23 / Chapter 2.5.1 --- Authority --- p.23 / Chapter 2.5.2 --- Management intensity --- p.26 / Chapter CHAPTER 3 --- INVENTORY OF PLANTER GREENERY / Chapter 3.1 --- Introduction --- p.30 / Chapter 3.2 --- Methodology --- p.33 / Chapter 3.2.1 --- Sampling --- p.33 / Chapter 3.3 --- Results --- p.36 / Chapter 3.3.1 --- Species composition --- p.36 / Chapter 3.3.2 --- Tree structure and size (physiognomy) --- p.40 / Chapter 3.3.3 --- Growth performance --- p.44 / Chapter 3.3.4 --- Tree growth problems --- p.45 / Chapter 3.3.5 --- Shrub and ground cover --- p.47 / Chapter 3.4 --- Discussion --- p.48 / Chapter 3.4.1 --- Inventory of planter greenery in the study areas --- p.48 / Chapter 3.4.2 --- Growth performance and problems --- p.57 / Chapter 3.5 --- Conclusion --- p.62 / Chapter CHAPTER 4 --- SELECTED PROPERTIES OF PLANTER SOILS / Chapter 4.1 --- Introduction --- p.65 / Chapter 4.2 --- Methodology --- p.67 / Chapter 4.2.1 --- Sampling --- p.67 / Chapter 4.2.2 --- Soil texture --- p.68 / Chapter 4.2.3 --- Soil reaction --- p.68 / Chapter 4.2.4 --- Organic carbon --- p.69 / Chapter 4.2.5 --- Total Kjeldahl nitrogen (TKN) --- p.69 / Chapter 4.2.6 --- Mineral nitrogen (ammonium and nitrate nitrogen) --- p.70 / Chapter 4.2.7 --- Total phosphorus --- p.70 / Chapter 4.2.8 --- Available phosphorus --- p.70 / Chapter 4.2.9 --- "Exchangeable K, Na，Ca and Mg" --- p.71 / Chapter 4.2.10 --- Carbon : nitrogen ratio --- p.71 / Chapter 4.3 --- Statistical analysis --- p.71 / Chapter 4.4 --- Results --- p.72 / Chapter 4.4.1 --- Soil texture --- p.72 / Chapter 4.4.2 --- Soil pH --- p.72 / Chapter 4.4.3 --- Organic matter --- p.73 / Chapter 4.4.4 --- Total Kjeldahl nitrogen --- p.74 / Chapter 4.4.5 --- Ammonium nitrogen and nitrate nitrogen --- p.75 / Chapter 4.4.6 --- Total phosphorus and available phosphorus --- p.76 / Chapter 4.4.7 --- Exchangeable cations --- p.78 / Chapter 4.5 --- Discussion --- p.80 / Chapter 4.5.1 --- Comparison with other studies --- p.80 / Chapter 4.5.2 --- "Are the planter soils optimal in pH, phosphorus and exchangeable cations?" --- p.84 / Chapter 4.5.3 --- "Deficiencies of SOM, TKN and mineral N" --- p.88 / Chapter 4.6 --- Conclusion --- p.91 / Chapter CHAPTER 5 --- NITROGEN AND PHOSPHORUS MINERALIZATION / Chapter 5.1 --- Introduction --- p.93 / Chapter 5.2 --- Methodology --- p.96 / Chapter 5.2.1 --- In situ incubation --- p.96 / Chapter 5.2.2 --- "Determination of N mineralization, leaching and uptake" --- p.98 / Chapter 5.2.3 --- "Determination of P mineralization, leaching and uptake" --- p.100 / Chapter 5.2.4 --- Statistical analysis --- p.101 / Chapter 5.3 --- Results --- p.102 / Chapter 5.3.1 --- Temporal changes of ammonification and nitrification --- p.102 / Chapter 5.3.2 --- Temporal changes of P mineralization --- p.103 / Chapter 5.3.3 --- "Net ammonification, NH4 leaching and uptake" --- p.104 / Chapter 5.3.4 --- "Net nitrification, N03 leaching and uptake" --- p.105 / Chapter 5.3.5 --- "Net N mineralization, leaching and uptake" --- p.106 / Chapter 5.3.6 --- "Net P mineralization, leaching and uptake" --- p.107 / Chapter 5.4 --- Discussion --- p.108 / Chapter 5.4.1 --- Comparison with other studies --- p.108 / Chapter 5.4.2 --- N mineralization in the planter soils --- p.112 / Chapter 5.4.3 --- P mineralization in the planter soils --- p.116 / Chapter 5.4.4 --- Leaching loss of mineral N and P in the planter soils --- p.118 / Chapter 5.4.5 --- Uptake of N and P in the planter soils --- p.121 / Chapter 5.5 --- Conclusion --- p.124 / Chapter CHAPTER 6 --- CONCLUSION / Chapter 6.1 --- Summary of findings --- p.127 / Chapter 6.2 --- Implications of the study --- p.131 / Chapter 6.2.1 --- Site-specific management programme --- p.131 / Chapter 6.2.2 --- Application of results --- p.134 / Chapter 6.3 --- Limitations of the study --- p.137 / Chapter 6.4 --- Suggestions for future study --- p.139 / REFERENCES --- p.142 / APPENDICES --- p.155

[Truncated abstract] Native vegetation (bushland) in urban areas remains in small, isolated patches embedded within a matrix of human-dominated land uses. Bushlands in urban areas have high biodiversity conservation and social values, and there has been a local-level movement towards protecting and managing urban bushlands in Australia. This thesis aims to test principles, theories and concepts relating to the ecology and management of bushland fragments in Australian cities ... A commonly used qualitative scale was compared with an ecologically based, quantitative technique developed in the research. The qualitative scale was found to be a reliable proxy for assessing vegetation condition, while also being more user-friendly for community groups and other bushland managers. The human-caused disturbances and weed cover in urban bushlands indicate a need for management intervention. Local government has an important role in local biodiversity management, yet there has been little research on this topic ... Positive partnerships developed where local governments have taken a ‘contract model’ approach to volunteer coordination, have a number of expectations of volunteer groups, and provide the groups with relatively high level of assistance. Also important is a local government that supports, respects, trusts and communicates with the community group, and recognises volunteers’ skills, knowledge and contributions. With increased resources allocated to local government bushland management and conservation, and coordination with community groups, the full potential of local bushland management would be realised.

published_or_final_version / Geography and Geology / Doctoral / Doctor of Philosophy

Dentre as variáveis que procuram mensurar a qualidade ambiental, a vegetação ganha destaque pela diversidade de serviços ecológicos prestados ao sistema urbano. Neste sentido, a análise das áreas verdes deve ser contextualizada em função do arranjo espacial dos principais elementos que exercem pressão sobre o ambiente. Por isto, trabalhamos com um índice de qualidade ambiental que integra variáveis clássicas como a proporção de cobertura vegetal, com outros elementos significativos da paisagem urbana como a extensão das áreas construídas e o adensamento vertical. Para o desenvolvimento deste índice aplicamos uma metodologia de Sensoriamento Remoto (SR) baseada na integração de ortofotos digitais e atributos altimétricos derivados do LIDAR (ALS) que permitiu mensurar a dimensão vertical da paisagem urbana tornando mais realística a modelagem dos efeitos das áreas construídas na qualidade ambiental. / Given the diversity of its ecological services, vegetation is among the main indicators of environmental quality in urban systems. For that, green areas must be analyzed in the context of the spatial distribution of the main elements putting pressure on the environment. In order to do that, we have worked with an index of environmental quality that integrates traditional variables, such as the proportion of vegetation cover, with other significant elements of the urban landscape, such as the extension of built areas and vertical densification. For the development of the index we applied a Remote Sensing (RS) methodology combining digital orthophotos and altimetric parameters based on LIDAR (ALS), which allowed to measure the vertical dimension of the urban landscape becoming more realistic modeling of the effects of the built environment on environmental quality.