Master of Landscape Architecture / Department of Landscape Architecture and Regional & Community Planning / Jessica Canfield / Located eight miles from the heart of Dallas, The Dallas Air Naval Station is a 1045-acre decommissioned airfield site. Since its closure in 1998, it has predominantly sat idle, bringing little value to adjacent neighborhoods and the greater community. Due to prolonged site remediation and no formal redevelopment plan, the site’s full potential has yet to come to fruition. Current urban design models tend to primarily focus on achieving a singular, end-result. However, as cities and the environment become more complex and unpredictable, these types of models often lack the ability to respond to change. Adaptive design, on the other hand, allows for more exploration of innovative practices, tools, techniques and methods that are informed by ecological knowledge and research design. As means of illustrating how adaptive design can catalyze and benefit brownfield sites, this project proposes an urban design framework informed by ecosystem services. Ecosystem services are an essential component to human well-being and environmental health, and when used as a guiding principle in site design, can add resiliency and beneficial outcomes to a site. To inform the development of the Ecosystem Services Urban Design Framework, this project uses literature, a site analysis, an applicable ecosystem services analysis, and precedent analyses. The framework is then applied to an urban brownfield site, the Dallas Air Naval Station, to show its applicability for short-term and long-term adaptive design scenarios. Dallas’ current issues and needs are addressed by the short-term plan, whereas informed projections of future issues inform the long-term design scenarios. Collectively, this project illustrates the imperative for incorporating adaptability into urban design, and for the value of using ecosystems services as underlying foundation.

The global market for wind energy is expanding rapidly, and in the last decade, Sweden has constructed thousands of wind turbines. The high installation pace suggests that a similarly rapid decommissioning rate is to be anticipated in the near future, notwithstanding the small number of turbines that have been retired thus far. There will be serious questions about the viability of wind power as a clean energy option if the decommissioned material by unfunctional turbines is not managed in a proper manner. The purpose of this research is to provide the distribution of Swedish installed wind turbine with the aspect of age, brand & model, hub height & rotor diameter, and nameplate capacity and also a reliable estimate of the total amount of decommissioned material that will be produced by wind turbines in Sweden over the next two decades. The results will represent to current characteristic of an industry to benefit the operation & maintenance activity and wind industry market research. Moreover, this will also help the waste management sector prepare for the inevitable increase in decommissioned material. The estimates are based on the installation dates, rotor diameter and other pertinent data included in vbk.lansstyrelsen.se, a Swedish national wind turbine map service. Applying the available data set with logarithmic function of rotor diameter and material fraction technique, the quantity of steel, iron, copper,aluminium, blade material, and electronics were generated. The material of each turbine is considered to be dismantled as wastes at 20 years after the installation date due to the industry average and comparison with empirical facts. As the results, the distributions show that most of Swedish wind turbines were installed between 2007 and 2016 and the most popular rated capacity ranged between 2 MW to 3 MW. Furthermore, the biggest market share belonged to Vestas, Enercon, and Siemens, respectively. The forecasted numbers reveal a large increase in decommissioned material weights year by year, and the blade material end-of-life management is the key concern when comparing the estimated number to Sweden's waste management capacity. Limitations associated with the suggested methodology and adopting data set are presented and discussed.

L’industrie minière de l’amiante a profondément transformé les paysages du sud du Québec, laissant environ 800 millions de tonnes de résidus miniers sous la forme de haldes près des villes minières telles Thetford Mines et Black Lake. Certains enjeux environnementaux découlant de ces paysages, notamment l’érosion des haldes par le vent et l’eau, ont été atténués avec succès sur certains sites en les recouvrant de technosols composés d’un mélange de matières résiduelles fertilisantes, puis en les ensemençant avec des graminées. Cependant, aucune tentative de boisement n’avait été faite jusqu’à présent, car ces milieux étaient considérés comme trop contraignants pour l’établissement et la croissance des arbres. Dans cette étude, nous avons développé deux plantations expérimentales dans une mine d’amiante en déclassement dans le sud du Québec, sur des stériles et sur des résidus miniers, dans lesquelles a été comparée la performance de huit espèces d’arbres, clones et provenances plantés sur deux types de technosols, tous deux construits à partir d’un mélange de biosolides municipaux et de boues de désencrage aménagés en andains. Les propriétés physiques et chimiques des technosols, comme l’état hydrique et l’activité ionique du sol, ainsi que la survie et la croissance des arbres, ont été évaluées. La nutrition foliaire et l’utilisation de l’eau ont également été étudiées pour trois clones de peupliers hybrides au cours de leur troisième saison de croissance. Les clones de peupliers hybrides avaient une survie significativement plus élevée (87 à 94 %) après trois ans que toutes les espèces de conifères (10 à 56 %) testées. L'espèce résineuse présentant les taux de survie les plus élevés était l'épinette blanche (46 à 56 %). Les conditions sèches lors de la mise en terre peuvent en partie expliquer les taux de mortalité plus élevés des conifères. Les taux de croissance moyens des peupliers hybrides étaient de 45 cm an-1, alors que certains arbres atteignaient plus de 300 cm de hauteur après trois ans. Le phosphore et le potassium étaient les nutriments qui limitaient le plus la croissance. Le clone DN×M-915508 semble être le plus tolérant à la sécheresse. Bien qu'il y ait peu de différences entre les technosols, les résultats suggèrent que l'ajout de sols contaminés de classe B au mélange de matières résiduelles fertilisantes a des avantages pour la survie et la croissance des arbres, probablement en raison du volume de sol plus élevé. Notre étude a démontré une technologie prometteuse pour la remise en état par le boisement des mines d’amiante du sud du Québec. Certains traitements devraient être ajoutés pour limiter la concurrence des plantes au cours des premières années afin d'augmenter la survie et la croissance des arbres, alors qu'un volume limité de technosol et donc une faible disponibilité en humidité et en nutriments pourraient compromettre la croissance à moyen et long terme des arbres. / The asbestos mining industry has deeply transformed the landscapes of southern Quebec, leaving about 800 million tons of tailings and waste rock in large piles near former mining towns such as Thetford Mines and Black Lake. Some of the environmental issues arising from these landscapes (e.g. wind and water erosion) have been successfully addressed at some sites by covering the piles with a mixture of by-products as the technosol and then seeding with grasses. However, no attempt for afforestation had been made thus far because these environments were thought to pose too many constraints on tree establishment and growth. In this study, we developed two experimental plantations at a decommissioned asbestos mine in southern Quebec, on waste rocks and on tailings, as a means to test the performance of eight tree species/clones/provenances planted on two types of technosols, both mainly constructed from the mixing of municipal biosolids and deinking sludge and configured in small windrows. Physical and chemical properties of technosols, including soil water availability and ionic activity, and seedling survival and growth were assessed. Foliar nutrition and water use were also evaluated for three hybrid poplar clones during the third growing season. Hybrid poplar clones had significantly higher survival (87 to 94%) after three years than all conifer species (10 to 56%) tested, although dry conditions at planting could have had adverse effects on conifers. The conifer species exhibiting the highest survival rates was white spruce (46 to 56%). Average growth rates of hybrid poplars were 45 cm y-1, whereas some trees reached over 300 cm in height after three years. Clone DN×M-915508 is believed to be more drought tolerant than the other hybrid poplar clones tested. Phosphorus and potassium were the most growth-limiting nutrients. Although there were few differences between the technosols, results suggest that the addition of Class B contaminated soils to the main mixture of by-products has benefits regarding tree survival and growth, likely because of its larger volume. Our study demonstrated a promising technology for reclamation through afforestation of asbestos mines in southern Quebec. Some treatments should be added to limit plant competition within the first few years as a means to increase survival and growth, whereas limited technosol volume and thus low moisture and nutrient availability could compromise mid- to long-term growth of trees.