A comprehensive understanding of the hydrodynamics in vegetated open-channels and flow-vegetation interaction is of high interest to researchers and practitioners alike for instance in the content of river and coastal restoration schemes. The focus of this study was to investigate the effect of the presence of vegetation on flow resistance, turbulence statistics, and the instantaneous flow in open channels by performing three-dimensional computational-fluid-dynamics (CFD) simulations. Firstly, fully developed turbulent flow in fully-vegetated channel was analyzed by employing the method of high-resolution Large-Eddy Simulation (LES). Flow through a staggered array of rigid, emergent cylinders was simulated and the LES was validated through experiments. After validation, numerical simulations were performed at an extended parameter range of two different cylinder Reynolds numbers (ReD = 500 and 1340) and three different vegetation densities (φ = 0.016, 0.063, and 0.251). Flow structures and statistics were analyzed on the instantaneous flow and the effect of the vegetation density and cylinder Reynolds number was assessed. Moreover, drag forces exerted on the cylinders were calculated explicitly, and the effect of both ReD and φ on the drag coefficient was quantified. Secondly, two new alternative simulation strategies, a RANS based strategy with a vegetative closure model and a low-resolution Large-Eddy Simulation, were devised. They were evaluated by simulating several experimental cases with diverse conditions of the cylinder arrangement (i.e., staggered vs. random distribution), vegetation densities (φ = 0.016, 0.022, 0.063, 0.087, 0.091, 0.150, and 0.251), and cylinder Reynolds number (ReD = 170 - 1700). For the RANS based strategy, the importance of a-priori knowledge was assessed, and for the low-resolution LES, the efficiency and accuracy was demonstrated. Finally, a numerical strategy based on a porosity approach was developed and applied to open-channel flow through a natural plant. The simulated velocities were compared with experimentally acquired ones and results showed reasonable agreement. The results obtained in this research contribute to the understanding of fundamental mechanism of flow-vegetation interaction in vegetated open-channels, resolving turbulent flow-vegetation interaction explicitly. In addition, the new numerical strategies developed as part of this research are expected to allow describing the behavior of turbulent flow through artificial and natural vegetation with high efficiency and accuracy.

Economic globalization in the 1980s ad 1990s gave birth to a new type of city, called a 'global city', which is assumed to perform critical functions to facilitate the contemporary global economy and which share the same characteristics. Cities, however, have different histories, economies, polities and demographies and these different local conditions do no lend themselves to the construction of a general model a global city even though they have characteristics. First, I explore the historical path of urban development in Seoul since the 1960s. Seoul is very unique in that its economic growth was mainly planned and implemented by the authoritarian Korean national government while civil and political freedom of citizens to participate the decision making process were strongly suppressed. However, the forces of globalization from the 1980s significantly altered the economic and political context in which the Korean state had successful operated in the previous decades. The role of state in regulating and planning the market was significantly weakened as well as the national political system became democratized and decentralized from the 1980s. These changes caused by the forces of globalization have made significant impacts on the organization of urban development in Seoul. Secondly, thus, I examine the social and political impacts of the globalization on the lives of the inhabitants in Seoul and I found that Seoul’s becoming a global city is closely related to the growing gap in the condition of living between the poor and the rich in Seoul. It is mainly caused by the restructuring of the urban labor market toward producer service sector orientation away from manufacturing sector. The expansion of the producer service sector has produced new trends in Seoul’s urban labor market: professionalization of regularly employed people at the top and increasing informal and low-skilled laborers and/or illegal foreign workers at the bottom. Moreover, it is found that increasing social inequality has its spatial consequence: a growing residential segregation. In Seoul, the southeast sub-region has emerged as an exclusive residential area for high-income professionals with much better living conditions, including spacious houses, easier access to heath-care facilities, more green space and educational institutions. The most important cause of the spatial concentration of professionals in this region is the concentration of the producer service sector jobs there. Yet, high price for housing in this area reinforces the clustering of the rich in the area and shuns lower-income people from moving into the area. However, the role of the national government cannot be under-estimated because the government urban policies produced the new development of residential and commercial development in the area in the 1980s. However, it is argued an opportunity to mediate the degrading economic living conditions for citizens in a global city has been created by the same force of globalization, yet in a different social system: urban politics. With particular emphasis on political democratization and decentralization under the current global economic system, it became possible for citizens to be directly involved in the public-policy making process. In theory, this situation implies that citizens are now empowered to create public policies that would minimize the negative consequences of economic globalization on their daily lives. My case study on Cheonggye Stream Restoration Project shows the opportunities and challenges of new urban political context in Seoul. The analysis of the Cheonggye Restoration Project suggests that more room has been created in the course of policy planning and the policy-making process, caused mainly by global political change toward direct democracy. However, the project also suggests that these changes at an institutional level did not lead to changes at an operational level, failing to produce an outcome that really reflects the demands of the actors. / text

Hydraulic geometry relationships and regional curves are used in natural channel design to assist engineers, biologists, and fluvial geomorphologists in the efforts undertaken to ameliorate previous activities that have diminished, impaired or destroyed the structure and function of stream systems. Bankfull channel characteristics were assessed for 14 United States Geological Survey (USGS) gaged sites in the Inner Bluegrass and 15 USGS gaged sites in the Outer Bluegrass Regions of Kentucky. Hydraulic geometry relationships and regional curves were developed for the aforementioned regions. Analysis of the regression relationships showed that bankfull discharge is a good explanatory variable for bankfull parameters such as area, width and depth. The hydraulic geometry relationships developed produced high R2 values up to 0.95. The relationships were also compared to other studies and show strong relationships to both theoretical and empirical data. Regional curves, relating drainage area to bankfull parameters, were developed and show that drainage area is a good explanatory variable for bankfull parameters. R2 values for the regional curves were as high as 0.98.

Thesis (M.S.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains viii, 138 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 81-85).

Thesis (M.S.)--Michigan State University. Dept. of Fisheries and Wildlife, 2008. / Title from PDF t.p. (viewed on Aug. 10, 2009) Includes bibliographical references (p. 64-68). Also issued in print.

ABSTRACT A review of annual monitoring reports for stream restoration projects on surface coal mines in the central Appalachian Mountains found that the criteria used for judging the success of the projects was generally based on visual assessments of habitat structure which were evaluated using the Rapid Bioassessment Protocol (RBP) (Palmer and Hondula, 2014). In recent years the Hydrogeomorphic Approach (HGM), which was originally developed to evaluate wetlands, has been adapted for stream evaluations as well (Summers, et al., 2017). Both of these methods are primarily a means to determine if suitable habitat structure and riparian growth are present to support aquatic life. It is assumed that if habitat structure is suitable then macroinvertebrate and other life will be present. However, each of these two methods place emphasis on different aspects of habitat and riparian structure. The primary purpose of this project is to compare and contrast how effective these two methods are at evaluating reconstructed streams on surface coal mines. A secondary objective is to determine if macroinvertebrate assemblages in reconstructed streams is significantly different from that of reference streams not impacted by mining. Research on benthic community structure downstream of coal mining activities suggests that even after many decades taxa richness and abundance still have not recovered from indirect impacts (Petty, et al., 2010). Information on reconstructed streams directly impacted is lacking. This project evaluates streams that were reconstructed five years prior using the RBP and HGM methods, and compares them to local reference streams that have minimal to no mining impacts. Multiple benthic metrics are also used to evaluate community structure. REFERENCES Petty, J. Todd, Jennifer B. Fulton, Michael P. Strager, George T. Merovich Jr., James M. Stiles, and Paul F. Ziemkiewicz. 2010. Lanscape indicators and thresholds of stream ecological impairment in an intensely mined Appalachian watershed. Journal of the North American Benthological Society, 29(4): 1292-1309. Palmer, Margaret A., and Kelly L. Hondula. 2014. Restoration as mitigation: analysis of stream mitigation for coal mining impacts in southern Appalachia. Environmental Science and Technology 48: 10552-10560. Summers, Elizabeth A., Chris V. Noble, Jacob F. berkowitz, and Frank J. Spilker. 2017. Operational Draft Regional Guidebook for the Functional Assessment of High-Gradient Headwater Streams and Low-Gradient Perennial Streams in Appalachia. ERDC/EL TR-17-1.

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