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Increasing interest among restoration ecologists exists in developing strategies that stimulate biotic interactions and promote self-regulation in restored systems. These approaches should target above- and belowground organisms because they interact to regulate ecosystem pattern and process. In the following dissertation, I compare the ability of organic amendments to alter above- and belowground biological community structure and function to promote prairie establishment on Castle Drive Landfill in Garland, Dallas County, Texas. Treatments included altering the location of organic amendments in the soil profile, either applied to surface or incorporated, and varying the amount applied. Plant community composition, grass population dynamics, soil nutrient conditions, and soil biological parameters were monitored for three growing seasons. Aboveground, the surface treatments were superior for the establishment of desired and undesired plant species. Plant density patterns can be attributed to the amelioration of physical conditions and the accidental burial of seed during incorporation. Grass population dynamics suggest that surface-amended plots supported establishment, but high-volume incorporated treatments were better for enhancing survival through seasonal and long-term drought. Belowground biological responses were affected by the plant community, and not by the amendment treatments. Soil microbial biomass and carbon mineralization potential were larger in those treatments with greater plant density. The structure of the nematode community suggests that decomposition in the surface-amended plots was directed through bacterial channels while decomposition in the incorporated plots was through fungal channels. It is likely that the higher rates of plant productivity in surface treatments stimulated root exudation, thereby favoring bacteria and the nematodes that feed on them. Treatment differences in decomposition pathway were attenuated after 17 months. The soil quality indicators, Cmic/Corg, qCO2, nematode family richness and nematode density, were not affected by the restoration treatments or plant density, but did increase over time. The results of this study suggest that restoration managers should direct their energies into establishing and promoting a high-quality plant community. This can be manipulated with amendments, but care is needed not to exceed thresholds within location treatments.

Thesis (M.S.)--Eastern Illinois University, 2008. / Includes bibliographical references (leaves 27-33).

Thesis--Wisconsin.

Thesis (M.Eng.)--University of Louisville, 2006. / Title and description from thesis home page (viewed Jan. 30, 2007). Department of Civil and Environmental Engineering. Vita. "December 2006." Includes bibliographical references (p. 108-111).

Thesis (M.S.)--Ohio State University, 2006. / Includes bibliographical references (leaves 95-102). Available online via OhioLINK's ETD Center

Thesis (M.A.)--Ohio University, June, 2003. / Title from PDF t.p. Includes bibliographical references (leaves 106-110)

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 2018 / The use of boulders to create habitat heterogeneity is important for aquatic diversity, and being able to predict the stability of a boulder that is placed in a river will aid in sizing the boulder. Identifying ways to increase the stability could save costs associated with over design or replacement due to the boulder washing away. Existing research on incipient motion centres on determining threshold conditions for bed material or protruding elements within a bed surface with relation to, among others: shape of particle, size of particle, relative depth of particle to flow depth, and impact of channel slope. The existing research is limited to bed material that is of a similar size and there is no research on the conditions for incipient motion elements that are relatively large compared to the bed material it is resting on. An idealised flume study was performed to identify trends that several factors have on boulder stability, as well as to verify the results obtained from a pivoting analysis model prediction for a spherical boulder. An additional study was performed to obtain drag coefficients that were suitable for use on spherical boulders that were either embedded into the bed material or simply resting on top of the bed material. The results of the drag experiments were varied; only the results for the non-embedded were suitable to integrate into the model predictions while drag coefficients for the embedded boulders need to be taken from previously published results. The results of the flume study provided good confirmation of the model predictions with the average absolute experimental error being 4%. The trends identified in the flume study show that the most effective method in improving a boulder’s stability is to embed it into the bed material with this being more effective than increasing the size of the boulder. / MT 2018

In the United States, stream restoration is currently a billion-dollar industry. Though it is commonly used as a method for stream impact mitigation, Total Maximum Daily Load (TMDL) crediting, and stormwater management, there is little scientific knowledge defending stream restoration as an effective tool for addressing these issues. In particular, few studies have been conducted with the goal of providing recommendations for future design improvements. To improve stream restoration success rates by advising practitioners and stakeholders in site selection and project assessment, a selection of completed Maryland stream restoration projects were assessed at the watershed and project level. Watershed, site, and design characteristics were quantified using ArcGIS, restoration design plans and monitoring reports. Using current literature and expert advice, stream restoration assessment methodologies were developed to assess geomorphic function and design success both in the field and through monitoring reports. Multiple linear regression analysis and related methods were then used to identify correlations and relationships between watershed- and project-level characteristics and stream restoration success. At the watershed scale, land use was most strongly related to functional success, with projects in more natural watersheds exhibiting higher geomorphic function. Design scores correlated negatively with watershed area. At the project level, projects with higher width to depth ratios scored higher on the functional assessment, while particle size was negatively correlated with geomorphic function. Study results suggest stream restoration designs are improving over time, but the ability to determine project success from monitoring remains limited. / Master of Science / In the United States, stream restoration is currently a multi-billion-dollar industry. Though it is commonly used as a method for water quality improvement, stormwater management, and habitat restoration after human disturbance, there is little scientific knowledge defending stream restoration as an effective tool for addressing these issues. In particular, few studies have been conducted with the goal of providing recommendations for future design improvements. To improve stream restoration success rates by advising practitioners and stakeholders in site selection and project assessment, a selection of completed Maryland stream restoration projects were assessed at the watershed and project level. Watershed, site, and design characteristics were quantified using spatial data analysis software along with restoration design plans and monitoring reports. Using current literature and expert advice, stream restoration assessment methodologies were developed to assess stream ability to transport water and sediment, as well as design resilience using monitoring reports, and during field visits. Data analysis showed projects built in more rural, natural watersheds were more similar to undisturbed streams. Projects constructed in large watersheds were less likely to remain stable after repeated storm events. At the project level, projects that were wider rather than deep were more functional, while those with significant amounts of large rock were less successful. Stream restoration designs seem to be improving with time, but the ability to determine project success from monitoring remains limited.

Thesis (M.S.)--University of Waterloo. / Includes bibliographical references.