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This project proposes a new urban aquifer strategy that utilizes stormwater to create a cascading plaza and an improved 'great street' in Washington DC. A system of urban aquifers is developed beneath the surface of the street, perched atop the compacted, impermeable soils below. This set of aquifers prevents stormwater from entering the existing combined sewer and allows trees to draw water from this new groundwater source and develop expansive root systems. On the surface, stormwater flows through interconnected planters where it irrigates and is filtered by vegetation before infiltrating to recharge the aquifer. At Cascade Plaza, sloping topography intersects the aquifer, and the new groundwater seeps out of the plaza steps, turning them into a miniature cascade, by gravity and water pressure alone. It collects in a web of runnels, pools at the lowest point, and overflows in high water, mysteriously disappearing below ground again to fill an underground reservoir. In this unique ecological system, water flows both above and below ground to mitigate excess stormwater and make the street and plaza more beautiful. / Master of Landscape Architecture / This project proposes a new urban aquifer strategy that utilizes stormwater to create a cascading plaza and an improved ‘great street’ in Washington DC. A system of urban aquifers is developed beneath the surface of the street, perched atop the compacted, impermeable soils below. This set of aquifers prevents stormwater from entering the existing combined sewer and allows trees to draw water from this new groundwater source and develop expansive root systems. On the surface, stormwater flows through interconnected planters where it irrigates and is filtered by vegetation before infiltrating to recharge the aquifer. At Cascade Plaza, sloping topography intersects the aquifer, and the new groundwater seeps out of the plaza steps, turning them into a miniature cascade, by gravity and water pressure alone. It collects in a web of runnels, pools at the lowest point, and overflows in high water, mysteriously disappearing below ground again to fill an underground reservoir. In this unique ecological system, water flows both above and below ground to mitigate excess stormwater and make the street and plaza more beautiful.

In the face of rapid urbanization and global climate change, urban trees and green spaces (UTGS) can contribute to the welfare of people and the urban environment. Urban trees and green spaces can assist to address urbanization challenges related to environmental degradation. While functions of UTGS have been well documented in the developed world, they have not yet received full attention in much of sub-Saharan Africa. Consequently, UTGS are under threat from urban development and fragmentation. Notably, the problems associated with UTGS also fall into the governance realm and indications are that poor governance and management of UTGS can negatively influence the potential benefits of UTGS to local people and the environment. This formed a basis for this research. The main objective of the study was to determine the current governance and management approaches to UTGS in South Africa. Through document search and review, the study determined the governance institutions influencing UTGS at national level and at provincial level (in the Limpopo and Eastern Cape Provinces). Face-to-face and online survey methods were used to determine the extent to which 28 local municipalities had adopted planned, systematic and integrated management of UTGS. The snowball approach was used to determine the key actors involved in UTGS activities and interviews were conducted to establish the roles and capabilities of these actors. A total of 540 household interviews were conducted to determine the institutional factors influencing local peoples’ ability to access, plant and use UTGS. The findings of the study showed that UTGS have not been adequately covered in existing governance institutions and practice at national and provincial levels. Local government municipalities were not managing their UTGS in a planned or systematic manner due to constraining factors such as insufficient funds, insufficient personnel, lack of equipment and lack of political support. Only 7.1 % of the surveyed municipalities had an urban tree management plan and an estimate of the urban tree stock; 32.1 % had tree policies; 28.6 % had tree bylaws; 21.4 % had tree planting schedules; 10.7 % had tree maintenance schedules and only 3.6 % had tree inspection schedules. Key actors involved in UTGS activities differed among levels of government. The actors included national and provincial government departments, local government municipalities, Non-Governmental Organizations, private sector companies and local volunteers. Most of the actors, however, either planted trees or provided tree seedlings to municipalities and the local people. Tenure security was a key institutional factor affecting peoples’ ability to plant, use or even remove trees from their residential plots. The same applied to trees in the streets and public parks. Whereas most respondents did not require permission to plant (79.8 %) or remove (75 %) trees on their residential plots, a majority of them required permission to plant and remove trees from streets (over 70 %) and public parks (over 80 %). However, with regard to planting and removing urban trees in public open spaces, 54% of the respondents indicated that permission was not required suggesting a lack of clarity among local residents on the issue. Overall, the findings of this study indicate that there is no political recognition and support for UTGS at almost all levels of government. This has resulted in the lack of incorporation of UTGS in urban planning and development and has caused UTGS to receive limited funding to permit planned and systematic management. Given the current rates of urbanization and urban development, the lowly prioritised UTGS are vulnerable to exploitation. To conserve UTGS and promote their potential contribution to local people and the environment, UTGS must be recognized and placed on political and development agendas. There is a need to develop national guidelines for UTGS management, assess the extent of the urban forest resource in local municipalities, clearly define the roles and capabilities of different actors, integrate UTGS in the urban planning and development system, and most of all seek to involve the local people in overall management and governance of UTGS.

In the past 25 years, Palm Beach County has acquired more than 31 million acres of public preserves consisting of numerous native habitats that are home to threatened and endangered flora and fauna. Both endemic habitats and plant species benefit from expansion and connectivity through the adoption of native plants in surrounding areas. The next step in conserving these protected, larger areas is to identify ways to connect them in order to reduce their isolation and improve their likelihood of continued ecosystem health. This study aims to perform an analysis using a GIS database of Palm Beach County's Eastern urban areas to determine additional vegetation that currently exists on public lands and private preserves and to analyze and classify the vegetation for its potential conservation role, either as ; preserves, buffers, corridors or clusters connecting and enhancing existing natural areas. / by Corrie Rainyn. / Thesis (M.A.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Insect pollinators provide indispensible ecosystem services for agricultural, natural and urban ecosystems, and have been declining drastically around the globe. These declines are largely due to fragmentation and loss of habitat resulting from urbanization and intensification of agriculture, and raise concerns over global food security. The purpose of this paper is to investigate the effects of urbanization on abundance, species richness and diversity of insect pollinators, and whether urban environments have potential as sites for conservation. Cities are highly heterogeneous environments with ample foraging and nesting opportunities and can house an abundance and diversity of pollinators. Urban environments can serve as refuges for many pollinator species. Effective city planning and mixed conservation strategies can help to promote healthy populations of insect pollinators in urban environments, which can help to stabilize populations in rural settings, thereby ensuring pollination services for agriculture and terrestrial ecosystems. / Pollinerande insekter (pollinatörer) bidrar med oumbärliga ekosystemtjänster till jordbruk och naturliga och urbana ekosystem, och de har minskat drastiskt i antal runt hela jorden. Dessa nedgångar orsakas till största del av habitatförstöring och -fragmentering, och väcker oro över den globala matsäkerheten. Syftet med den här uppsatsen är att undersöka hur urbanisering påverkar abundans, artrikedom och biodiversitet hos pollinatörer, samt om urbana miljöer har potential som platser för bevarande av pollinatörer. Städer är mycket heterogena områden med gott om matresurser och boplatser, och kan husera en mångfald av pollinatörer. Urbana miljöer lämpar sig bra som platser för bevarande av pollinatörer. Med effektiv stadsplanering och en blandning av olika bevarandestrategier kan städer uppehålla hälsosamma populationer av pollinatörer. Detta kan hjälpa till att stabilisera populationer på landsbygden och därmed säkerställa pollinationstjänster till såväl jordbruk som naturliga terrestra ekosystem.

This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with development in surrounding landscapes were measured in situ. GIS delineation was conducted to define landscape-scale variables at stratified distances from riparian networks up-stream of each site via the utilization of the 2006 NLCD dataset and a finer-scale, regional dataset compiled by the Institute for Natural Resources (INR). Amphibians were detected at seventeen of the thirty-seven sampled streams. The most commonly detected species were Dicamptadon tenebrosus, Plethadon vehiculum and Plethadon dunni. Streams where amphibians were observed had lower average water temperature and conductivity, coarser stream substrate and were located on public property more often than streams where no amphibians were detected. Landscape variables were most significant to amphibians within 100 and 200 meters of the upstream stream network. Occupancy of a site by facultative species was best explained by the proportion of mixed forest in the surrounding watershed (R2=0.343, p<0.001). Occupancy of a stream by obligate species was best predicted by measurements of water quality and in-stream cover (Water Temperature: R2=0.275, p<0.001; Water Conductivity: R2=0.248, p<0.001; Cover: R2=0.323, p<0.001). Occupancy of stream refugia by all observed amphibians was positively influenced by higher percentages of forest cover and lower percentages of urban development and herbaceous vegetation in the surrounding watershed. Results of this study indicate that urban refugia must contain adequate riparian forest area, coarse stream substrate and clean, cool water to sustain stream-amphibian communities. Protection of remnant forested headwater stream networks is essential to the conservation of lotic amphibians in this urbanized region.

The growing urban population in South Africa has challenged the government's ability to provide adequate housing for the urban poor. In order to respond to the challenges, the government embarked on the initiative of providing Low - Income Housing (L1H). There is, however, a growing concern that these L1H developments may not be sustainable due to a number of reasons, including issues relating to land use and sub- standard construction of houses. There is need to make these L1H areas more sustainable. This can be done by employing the concept of the sustainable city. The concept in recent times has been considered by many people as an ideal to which cities should aspire. The main thrust of this study is to evaluate the concept of the sustainable city in the context of L1H in Ambleton, a settlement constructed by the government to relocate people from illegal, informal settlements within the inner city especially those found adjacent to the industrial areas. The study focuses on the issues of land use in L1H. This focus on land use is underpinned by the fundamental views that land use contributes to urban sustainability. As a result, it is necessary to examine ways in which land is being used in L1H areas and see if the current land use in Ambleton contributes to sustainability. The study shows that some people are satisfied with the amount of open spaces around their houses. Many others, however, are not satisfied because they considered open spaces in .their yard inadequate. Furthermore, public open spaces are not properly managed because there are no services to manage it. In the same vein, people have to travel long distances to get to their places of work and town for economic and leisure activities. Similarly, the provision of waste services and medical services in the study area is grossly inadequate. The study argues on that basis that the above scenario is not in accordance with the concept of sustainable city and can not therefore contribute to, the sustainability of the area of study. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

Traditionally New Zealand ecological research has focused on nature outside of cities, however, as with global trends, there is now more interest being given to the ecological functioning of cities and the potential they may hold for protecting native biodiversity. Traditionally, efforts to maintain biodiversity in urban areas have been restricted to remnants of native vegetation and restoration activities. Little attention has been given to how native biodiversity could be woven into the urban fabric in an ecologically meaningful way. One option, that is receiving much attention overseas, is to recruit underutilised urban spaces such as wasteland. A subset of urban wasteland, abandoned industrial areas usually awaiting development and other areas such as the railway buffer, are referred to here as greyfield. These are ephemeral sites that may sit between uses for as little as a few months to many years. Overseas, particularly in European countries, these have been recognised as important habitat for both native and introduced plant species. In New Zealand cities these support primarily introduced plants and their contribution to native biodiversity has been unknown. This thesis took an interdisciplinary approach to the question of whether urban greyfields might have potential value as biodiversity protection and conservation opportunity. Ecological methods were combined with an assessment of the planning framework to answer this question. iii Greyfields in Christchurch, New Zealand were surveyed to determine their current contribution to native biodiversity and whether they may act as urban analogues of natural habitats. Overseas research has shown that urban features such as pavements, walls and rooftops offer habitats analogous to cliffs and rocky habitats. Cities are therefore increasing the habitat exploitable by species whose natural habitats are geographically restricted. The Christchurch greyfields were assessed for their potential to act as analogues of four habitat types that have been categorised as historically rare in New Zealand: braided riverbeds, shingle beaches, rock outcrops and limestone outcrops. The findings suggest that urban greyfields, if managed appropriately, have the potential to support a wider range of native species Planning documents and biodiversity strategies written for Christchurch were assessed to see how well they facilitated non-traditional biodiversity enhancement initiatives, specifically the greyfield network for native biodiversity. A major finding here was a lack of information on how to enhance biodiversity where little of the natural features of the landscape were left and that this was creating a barrier to adopting more integrative approaches to enhancing native biodiversity. Finally, a plan to create a greyfield network for native biodiversity is proposed and suggestions are made as to minor changes to the planning framework that would more easily facilitate the uptake of novel biodiversity enhancement initiatives in the City.