Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 97-101).

Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 97-101).

Thesis (M.S.)--California State University, Chico. / Includes abstract. "Located in the Chico Digital Repository." Includes bibliographical references (p. 67-73).

Thesis (Ph. D.)--George Mason University, 2004. / Includes bibliographical references (leaves 197-207).

As the Americans have become more aware of the impact to the environment from the human induced disturbances which includes physical, chemical and biological disturbances to the degradation of streams and rivers, many studies and experiments have been done in an attempt to restore streams and rivers to more natural conditions. At the same time, success in public education and community involvement has encouraged grass-root movements that engage people in stream restoration efforts. Stroubles Creek is a freshwater stream located in Blacksburg, Virginia. The creek has experienced considerable disturbance due to land use changes over the past 100 years. The Stroubles Creek Water Initiative (SCWI), originated by the Virginia Water Resources Research Center at Virginia Tech, has been monitoring the creek for a number of years. This paper develops a planning framework for restoring and/or rehabilitating Stroubles Creek within the Town of Blacksburg. The results of stream monitoring and other research by SCWI are used to inform the recommended planning process, while a literature review and discussion of “urban stream restoration case studies” are used to guide future decision-making related to Stroubles Creek restoration/rehabilitation. / Master of Urban and Regional Planning

No description available.

Thesis (Ph.D.)--University of Melbourne, School of Anthropology,Geography and Environmental Studies and the Dept. of Civil and Environmental Engineering, 2006. / Typescript. Includes bibliographical references.

Riparian wetlands may provide numerous ecosystem services, including water quality protection, food and fiber supply, wildlife habitat, and carbon sequestration. In recent years, riparian forests have received increased attention and funding for riparian forest restoration projects. Unfortunately, failures of riparian restoration efforts are likely due to mortality of planted trees. Tree mortality is commonly attributable to several factors, including selection of species that are not well suited to the wetland sites, inadequate planting densities, soil compaction associated with former agricultural activities, lack of microtopographic relief that allow small seedling to survive on wet sites, competition by herbaceous plants, and browse. Selection of well-suited species, dense planting and use of mechanical soil site preparations are all potential remedies to partially address success of wetland restoration plantings. Riparian restoration projects have historically been undertaken with goals of improving water quality and/or wildlife habitat, but in recent years there has been increased valuation of carbon sequestration. Carbon valuation appears to be increasing, but more research is needed to determine rates and pools of carbon accumulation in riparian areas. Our research quantifies forest establishment effects on multiple carbon pools in a densely planted, 12-year-old old-field riparian restoration. Our research evaluated the effects of four soil mechanical site preparations (bed, disk, pit, and mound and rip) and species selection (American sycamore (Platanus occidentalis) and willow oak, (Quercus phellos) on forest establishment and carbon storage across multiple pools, namely in planted trees, herbaceous vegetation, fine roots, organic soil horizons, and the mineral soil. At 12 years, we found that species selection was more important to carbon storage than site preparation. American sycamore was well suited to the site and had better survival than willow oak (64% vs 42% survival). American sycamore also stored more carbon across all site preparations than willow oak. Measured carbon storage averaged 74.8 Mg ha-1 for American sycamore treatments and 63.1 Mg ha-1 for willow oak treatments. The plots were densely planted (1.2 m (4ft) by 1.8 m (6ft) spacing), and forests were established even in higher mortality willow oak plots. These results indicate that high planting density is potentially a viable practice for establishing riparian forest cover, especially if desired species are marginally site suited or other survival inhibiting factors exist. / Master of Science / Riparian forests located within the floodplain of streams are known to protect stream water quality, provide wildlife habitat, and store carbon. Due to these benefits, trees may be replanted on riparian areas that were formerly used for agriculture. Unfortunately, trees planted on these restoration sites have often died. The tree mortality may be due to planting incorrect tree species that may struggle on wet floodplains, soil compaction from agricultural practices, not enough trees being planted, and restored floodplains lacking small, elevated areas common across natural wetlands known to favor tree rooting and survival. Reasonably, selecting species that are well suited to a specific site, planting trees more densely, and using plowing methods designed to break up compaction and create some relief in elevation would amend these issues. Traditionally, floodplain restorations have focused on improving water quality and providing habitat for wildlife, but the benefits of storing carbon have become increasingly valuable in recent years. While we know that wetlands store carbon, research is needed to examine how quickly and where carbon is stored. Our research quantifies forest establishment and carbon storage of very densely planted, 12-year-old American sycamore (Platanus occidentalis) and willow oak (Quercus phellos) plantations. This research examines the effects four soil tillage methods and tree species selection had on tree survival and carbon storage. Carbon storage was measured in vegetation, soil, and small roots. Twelve years after planting, species selection had a greater impact on carbon storage than soil tillage methods. No tillage method altered survival or total carbon after 12 years, but American sycamore was found to have better survival and more carbon than willow oak in all soil tillage treatments. Both species were successful in establishing planted forests on the floodplain, but the success was aided by the very high initial numbers of planted trees that ensured enough trees would survive on the site even after trees were lost to mortality. Creation of willow oak forests benefitted more from dense planting, as it was less suited to the site and more planted willow oaks died. We recommend tillage for compacted soil, selecting the most suitable tree species, and planting adequate numbers of trees.

The most recent surveys in South Africa estimate that invasions are still increasing, despite substantial clearing efforts. Riparian systems in South Africa are particularly vulnerable to invasion by woody IAPs. This thesis addresses the restoration of alien‐invaded riparian systems, by investigating the factors that facilitate or constrain spontaneous recovery and influence the trajectories of succession. These factors include invasion history and management history, especially the use of fire. A seedling emergence approach was used to test the presence of a viable pre‐fire seedbank, and the effect of fire on the seed bank. The efficacy of some active restoration interventions was also tested, with the aim to return invasion‐resistant, indigenous vegetation with a structure and function representative of uninvaded sites. The findings of this study indicated the presence of a viable and persistent riparian soil seed bank, even after 30 years of intermtittent invasion as well as two fire cycles under invasion. It shows that the management practice of fell‐and‐burn resulted in high soil temperatures, and that this reduced the indigenous soil seed bank density, especially in the upper soil layer. Clear germination sequences and patterns of emergence over time for different species were observed during this study, with many species exhibiting delayed emergence relative to the timing of the fire event. It is proposed that manipulation of the season of fire could be used to selectively optimise the order of arrival and therefore superior recruitment of some species over others in the Eastern Cape fynbos, and thus alter the trajectories of recovery of vegetation towards a more desired state. Active restoration in the form of indigenous seed and plant additions resulted in a significantly higher indigenous cover after seven months, compared to a control (passive restoration) or restoring with grass. Indigenous cover and composition was also strongly influenced by lateral zonation, and some key guilds and species were missing or present in much lower densities compared to reference sites. Grass restoration significantly suppressed the regeneration of A. longifolia, as well as the regeneration of indigenous species. Biotic resistance can thus be achieved through restoration, and it could be a powerful tool in the management of IAPs, although the deliberate introduction of grass after clearing in fynbos also reduces biodiversity and could have unforeseen consequences to riparian function.

Water quality in streams around the world continues to be degraded by a series of human activities that feed pollutants into the vulnerable stream ecosystem via surface and subsurface runoff. This continues to accelerate global biodiversity and habitat losses within the stream environments and across entire watersheds with net adverse effects on public health and the ability of communities and ecosystems to adapt or become resilient to the prevalent impacts of climate change. One commonly used approach for protecting stream water from pollution is the use of vegetated riparian buffer zones to mitigate pollutants in surface and subsurface runoff prior to runoff entry into the stream channel. The optimal success of this approach requires land and water resource managers to understand the mechanisms by which riparian buffer zones function and the full range of factors that influence the effectiveness of riparian buffer vegetation in abating stream water pollution. Despite this need, resource managers in different geographical locations around the world still struggle to understand the linkages between riparian vegetation and stream chemical quality. This literature review therefore sought to synthesize findings from various scientific articles on the ways in which the major attributes of riparian vegetation [type, age, width, restoration and shading effect] influence the effectiveness of riparian vegetation in protecting the chemical quality of water in streams. This was aimed at generating conclusions and perspectives that could improve academic knowledge and natural resource managers’ understanding of the intricate linkage between riparian vegetation and changes in water chemistry. The study finds that the factors of riparian vegetation type, age, width, restoration and shading effects require due consideration in the development of riparian buffer zone and stream water chemical quality management interventions. I find that these factors require a high degree of integration, triangulation and context-specificity to achieve the objectives of riparian management intervention. I further find that stream water quality decision-making processes need to combine riparian vegetation-based approaches with other measures for mitigating and containing the spillage of pollutants at the source. / <p>Presentation was conducted via Skype</p>