Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 277-296).

Thesis--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.39-44).

Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vii, 129 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 36-39).

Thesis (M.A. Sc.)--University of Toronto, 2005. / Source: Masters Abstracts International, Volume: 44-02, page: 0974.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Urban forests have been shown to impact residential property values. This research demonstrates the results of a hedonic pricing study to determine the impact of canopy cover on single family residential property values in Lakeland, Tennessee during the period 2001-2005. The influence of canopy cover was evaluated on the lot within buffers of 100m, 500m, and 1km surrounding the lot. The study shows that canopy cover on the lot was not a significant contributor to property values while canopy cover in the buffers had a significant positive influence on home sales prices. Results also indicate that the increased property values lead to increased municipal tax revenues of 1.2-1.7% for every 10% increase in canopy cover. Results of this study can be used to develop similar processes and analyses leading to subsequent benefit-cost ratios for urban forestry programs while providing guidance on strategic tree retention and replacement efforts.

There are many documented environmental benefits to concentrating populations in cities. However, the impermeable nature of modern urban landscapes, which has been created by roads, buildings, and paved public spaces, has altered the natural cycle of water through today’s cities. As a result, a greater fraction of rainfall becomes runoff, creating stormwater pollution that degrades the very host environments needed to support city living. One attractive approach to urban stormwater management is the use of engineered and non-engineered vegetative systems to reduce the amount of rainfall that becomes runoff. When one considers the vast number of vegetative systems needed to bring about significant change, along with the variety of environmental niches in the urban landscape, it is clear that an array of “greening” strategies are needed. In turn, accurate performance data and models of these strategies are necessary to appropriately inform design and policy decisions. The research presented in this dissertation focuses on advancing the understanding, modeling, and design of three types of vegetated infrastructure with potential to address urban stormwater challenges: extensive green roofs, street trees, and vine canopies. The first research focus examines a nuance to a well-developed and well-studied technology: the extensive green roof. Nearly four years of environmental and runoff monitoring data from two full-scale extensive green roofs are used to determine how the time of year impacts hydrologic performance while considering the covariates of antecedent dry weather period, potential evapotranspiration and storm event size. Comparisons are made between thick and thin extensive green roof systems, and novel models are presented which account for seasonal variability. The second research focus evaluates the absorptive capacity of an existing type of urban vegetation: the street tree. In particular, this work looks at the permeability and infiltration capacity of the tree pit’s soil surface, which is often a controlling factor in the hydrologic performance of street trees. The resulting model links physical features of the tree pit to its ability to absorb water. Furthermore, the results indicate two simple, low-cost management strategies to improve urban stormwater capture via street trees. The third research focus explores the stormwater management potential for a new type of vegetated infrastructure: the horizontal vine canopy. Hydrologic performance data from sixteen vine canopies grown on a New York City rooftop are used to determine the capacity of the vines to retain stormwater, return water to the atmosphere via transpiration, and grow in the harsh rooftop conditions. Models and coefficients describing stormwater capture and plant transpiration are then presented and used to estimate the potential capacity of vine canopies to contribute to urban stormwater management. Exploration into new forms of vegetated infrastructure and facets of existing urban vegetation through the perspective of stormwater management has resulted in valuable findings and experimental methodologies. In several instances, these studies required new measuring equipment or sampling procedures, which were developed, validated, and made available for future research.

<p> In cities, microclimates are created by local mixtures of vegetation, constructed materials, vertical structure, and moisture, with significant consequences for human health, air quality, and resource use. Vegetation can moderate microclimates through evapotranspiration, however this function is dependent on local conditions so its effect may vary over space and time. This dissertation used hyperspectral and thermal remote sensing imagery to derive key observations of urban physical and biophysical properties and model urban microclimates across the megacity of Los Angeles. In Chapter 1, I used Multiple Endmember Spectral Mixture Analysis (MESMA) to map sub-pixel fractions of different vegetation types, as well as other types of urban cover, at 4 m and 18 m resolution over Santa Barbara, California (Wetherley et al., 2017). Fractional estimates correlated with validation fractions at both scales (mean R² = 0.84 at 4 m and R² = 0.76 at 18 m), with accuracy affected by image spatial resolution, endmember spatial resolution, and class spectral (dis)similarity. Accuracy was improved by using endmembers measured at multiple spatial resolutions, likely because they incorporated additional spectral variability that occurred across spatial scales. In Chapter 2, I applied this methodology to derive sub-pixel cover for the greater Los Angeles metropolitan area (4,466 km²) (Wetherley et al., 2018). Further improvement in quantifying sub-pixel vegetation types was achieved by modifying the MESMA shade parameter. Land surface temperature (LST), derived from thermal imagery, was used to model temperature change along vegetation fractional gradients, with slopes of LST change showing significant differences between trees and turfgrass (p &lt; 0.001). Expected per-pixel LST was derived from these gradients based on sub-pixel composition, and when compared to measured LST was found to deviate with a standard deviation of 3.5 &deg;C across the scene. These deviations were negatively related to irrigation and income, while building density was observed to affect tree LST more than it affected turfgrass LST. In Chapter 3, I used the map of Los Angeles landcover, along with data from LiDAR, GIS, and WRF climate variables, to parameterize an urban climate model (Surface Urban Energy and Water Balance Scheme: SUEWS) for 2,123 neighborhoods (each 1 km²) across Los Angeles. Modeled latent fluxes were correlated with remote sensing LST (R² = 0.39) collected over a period of 5 hours, with an overall diurnal pattern modified by irrigation timing. Spatial variability across the study area was related to local landcover, with albedo and vegetation fraction strongly influencing latent and sensible fluxes. A strong regional climatic gradient was observed to affect latent fluxes based on coastal proximity. Overall, this dissertation quantifies the key drivers of urban vegetation function in a large city, and further demonstrates the potential of hyperspectral and thermal imagery for observing city scale surface and microclimate variability.</p><p>

Over 80% of Sweden's population lives in urban areas, and half of the country's forest visits will thus be in urban woodlands. Social values ​​- how the individual experiences the forest, and the impact of the forest visits on individual health and well-being, are pointing to the importance of managing the urban woodlands. When there comes to the cultivation of the urban woodlands there are usually many opinions to consider. This study aims to investigate the various opinions on the use and forestry in an urban recreation area in ​​the City of Trollhättan. The study addresses both general and in four cases specific suggestions on management methods. Data was obtained from both quantitative and qualitative study through survey, interviews and discussions with the users of the recreation area. Trollhättan's goal with the recreation area is to make it accessible to local residents. The users are mainly influenced by the accessibility therefore clearings and thinnings are appreciated. Clear cuts should be avoided, but can be used as a method if logging residues are removed afterward. Variation is important for the specific areas, the focus is laid on hardwood species. Where hardwood is missing the focus should be to create old and sparse forest.