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- All Subjects: Sustainability
- Creators: Wiek, Arnim
In recent years, an increase of environmental temperature in urban areas has raised many concerns. These areas are subjected to higher temperature compared to the rural surrounding areas. Modification of land surface and the use of materials such as concrete and/or asphalt are the main factors influencing the surface energy balance and therefore the environmental temperature in the urban areas. Engineered materials have relatively higher solar energy absorption and tend to trap a relatively higher incoming solar radiation. They also possess a higher heat storage capacity that allows them to retain heat during the day and then slowly release it back into the atmosphere as the sun goes down. This phenomenon is known as the Urban Heat Island (UHI) effect and causes an increase in the urban air temperature. Many researchers believe that albedo is the key pavement affecting the urban heat island. However, this research has shown that the problem is more complex and that solar reflectivity may not be the only important factor to evaluate the ability of a pavement to mitigate UHI. The main objective of this study was to analyze and research the influence of pavement materials on the near surface air temperature. In order to accomplish this effort, test sections consisting of Hot Mix Asphalt (HMA), Porous Hot Mix asphalt (PHMA), Portland Cement Concrete (PCC), Pervious Portland Cement Concrete (PPCC), artificial turf, and landscape gravels were constructed in the Phoenix, Arizona area. Air temperature, albedo, wind speed, solar radiation, and wind direction were recorded, analyzed and compared above each pavement material type. The results showed that there was no significant difference in the air temperature at 3-feet and above, regardless of the type of the pavement. Near surface pavement temperatures were also measured and modeled. The results indicated that for the UHI analysis, it is important to consider the interaction between pavement structure, material properties, and environmental factors. Overall, this study demonstrated the complexity of evaluating pavement structures for UHI mitigation; it provided great insight on the effects of material types and properties on surface temperatures and near surface air temperature.
I review historical trends in international development that led to the popularity of both sustainable development and beneficiary participation. This review identifies central themes in defining beneficiary participation and motivations for using it.
I also developed a new typology of beneficiary participation based on a literature review of how scholars define beneficiary participation. I found that the main dimensions of beneficiary participation are (1) participants, (2) channels, (3) types of inputs, (4) timing, and (5) goals. By making these dimensions explicit, this work helps researchers and development practitioners more clearly describe the types of beneficiary participation they study, employ, and advocate for.
To contribute to empirical literature about beneficiary participation, I conducted a case-study of two urban development projects in Bhopal, India. I collected data with a structured survey of project beneficiaries in four slums (two slums from each project) and semi-structured interviews with each project's organizers. And project documents provided secondary data on both projects. The results indicate that local elites did not capture a disproportionate share of either project's benefits, at least with respect to individual household toilets. Because project organizers rather than beneficiaries selected households that would receive toilets, both cases serve as counterexamples to the claim that beneficiaries must intensely participate for projects' benefits to be distributed equitably.
Finally, I review academic literature for empirical evidence that supports claims about the advantages of beneficiary participation. There is relatively strong empirical support for the claim that beneficiary participation improves project outcomes, but empirical support for most other claims (i.e., that it helps make projects more efficient, distribute benefits equitably, and sustain project benefits) is weak. And empirical research suggests that one claimed benefit, empowerment, rarely materializes. In general, more empirical research about beneficiary participation is needed.