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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Relationships between soil fertility and species-richness in created and semi-natural grasslands in the English West Midlands

McCrea, Alison R. January 1999 (has links)
No description available.
2

The manipulation, introduction and ecology of field layer communities in broadleaved woodlands

Cohn, E. January 1994 (has links)
No description available.
3

Riverfront remediation: redevelopment for human access and wildlife health

Swehla, Tyler January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Alpa Nawre / Historically, industrial riverfronts often polluted waters and sites with chemicals, leading to degraded ecosystem health and reduced numbers of aquatic wildlife downstream. These sites currently pollute the environment through residual chemicals and waste left behind by industrial-era production factories. Urban riverfront redevelopment offers many possibilities to restore wetland ecosystems and reestablish site connections to surroundings through human access. By redeveloping urban rivers for wetland protection and stormwater management, cities can begin to regain their connections with the landscape while providing resilient ecosystems through restoration. This proposal identifies possibilities for riverfront redevelopment as wetlands and tools for restorative action aiding increased human access and wildlife health. A stormwater management plan utilizing phytotechnology is proposed for the ARMCO Site at 7000 Winner Rd. Kansas City, MO, a former steel manufacturing site, adjacent to the Missouri River and Blue River waterways. Using plant material and landscape design, the ARMCO riverfront has been redesigned to unlock the full potential of treatment wetlands and showcase emerging treatment methods that could soon become typical cleanup procedure. A template for remediation design has been created with the techniques identified for remediation, stormwater treatment, and habitat creation outlined in the master plan proposal. Nine precedent studies have been used to identify key concepts for design phasing aimed at human accessibility and modifications of restorative tools. Careful deliberation of stormwater containment and flood plain levels define site layout while contributing design responses adaptable for year-round functionality coupled with landscape interest for each season. The techniques and planting palette have been tailored to address the specific site contaminants for the Missouri River riverfront but are adaptable for various contaminants and ecosystems.
4

Ecological Coexistence: A Nature Retreat and Education Center on Rattlesnake Key, Terra Ceia, Florida

Peterika, Richard F 21 November 2008 (has links)
Applied ecology has been used to design communities around the world; however suburban neighborhoods in west central Florida do not usually utilize existing or potential ecological function as a modeling parameter or success measure. Since the end of the great depression, developments in the Tampa Bay Area have displaced many wetland and upland natural communities. Private ownership and development of sensitive natural lands have restricted their use and hampered the functional longevity of important ecological systems in this area. These displaced areas have historically functioned as habitat for many types of animal life, have passively conveyed nutrient loads, and have facilitated the succession of organisms. They have also been used as recreational opportunities for local residents and visitors, children and adults. Applied ecological design usually occurs at a community or master plan scale, or separately at a singular building level, but rarely both simultaneously. This design proposal was the investigation and formation of an ecocentric architectural design methodology for coastal environments; from master plan to conceptual building design. The scope was the synthesis of a recreational tourism facility with the existing ecological communities of Rattlesnake Key, a barrier island in northwest Manatee County, Florida. The program included an ecological education center, where visitors could learn about their relationship with the ecological communities present on the island, and a group of cabins, where inhabitants could interact with each other and the surrounding natural communities intimately. Master planning strategies were outlined using extensive ecological mapping overlays, in-field observation, and feasibility analysis. Building forms, means of construction, and structural systems were created by integrating biomimicry methods, habitat restoration techniques, and sustainable practices into a programmed, built environment. The results of the investigation were a series of physical models and graphic representations of spaces that manifest the sensitive relationship between human inhabitance and ecological function; where both processes coexist and support the longevity and persistence of one another through habitat creation. By analyzing the existing ecological functions present on a site, a designer could propose a typology that strengthens the relationship between man and his environment; where development is no longer displacement.
5

The prairie above: a regional investigation into the green roof technology and application

MacArthur, Shauna 26 April 2012 (has links)
Issues associated with urban development such as the urban heat island effect, loss of habitat, increased areas of impervious surfaces leading to storm water management concerns are well known. Many designers, engineers and policy creators are sensitive to these issues creating positive change by implementing alternatives to traditional development. Although, the concept of green roofs is not new to the prairies, modern development of this technology has not been fully embraced. Surrounded by concerns of efficacy and longevity here in the harsh northern prairie climate, green roof development and implementation has been slow. The objective of this practicum is to determine what green roof system and what vegetation of the short grass / fescue prairie and mix grass prairie would succeed in a green roof setting. Determining the appropriate planting palette and growth medium depth for the Canadian Prairies is essential for the development of the green roof industry locally.
6

The prairie above: a regional investigation into the green roof technology and application

MacArthur, Shauna 26 April 2012 (has links)
Issues associated with urban development such as the urban heat island effect, loss of habitat, increased areas of impervious surfaces leading to storm water management concerns are well known. Many designers, engineers and policy creators are sensitive to these issues creating positive change by implementing alternatives to traditional development. Although, the concept of green roofs is not new to the prairies, modern development of this technology has not been fully embraced. Surrounded by concerns of efficacy and longevity here in the harsh northern prairie climate, green roof development and implementation has been slow. The objective of this practicum is to determine what green roof system and what vegetation of the short grass / fescue prairie and mix grass prairie would succeed in a green roof setting. Determining the appropriate planting palette and growth medium depth for the Canadian Prairies is essential for the development of the green roof industry locally.
7

Piping plover habitat and demography following storm-induced and engineered landscape change

Robinson, Samantha G. 16 April 2020 (has links)
Understanding the effects of large-scale disturbances and associated management actions on imperiled species can increase conservation value of future management. Piping plovers (Charadrius melodus) are federally threatened and endangered, disturbance-dependent shorebirds, nesting on broad, sparsely vegetated beaches, sandbars, and lakeshores. In October 2012, Hurricane Sandy storm surges cleared vegetation and opened old and new inlets through Fire Island and Westhampton Island, New York, creating plover habitat. Storm effects prompted an island-wide stabilization project, and certain sections of Fire Island were designed to create and/or improve plover habitat (hereafter, restoration areas) to mitigate possible habitat loss or degradation. Many plover populations range-wide appear to be habitat-limited, and we anticipated positive population growth following habitat creation. To help predict what might happen to the plover population following Hurricane Sandy, we evaluated the effects of habitat-creating events at several other locations in the range, evaluating the hypothesis that plover population sizes are habitat limited. We estimated the amount of habitat available before and after four significant storm and flooding events by classifying pre- and post-disturbance aerial imagery and evaluated the population changes that occurred after disturbance-related habitat alterations. Following these habitat creating events, nesting habitat increased 27%–950%, and, subsequently, these plover populations increased overall 72%–622% (increase of 8–217 pairs in 3 to 8 years after the disturbance, average 12–116% increase annually). The demographic changes likely were driven by some combination of productivity and immigration occurring simultaneously with regional increases. We then evaluated population and suitable habitat change on Fire Island and Westhampton Island following Hurricane Sandy. We developed an integrated population model to determine the primary contributors to population and assessed the effect of restoration areas on demographic processes during 2013–2018. We also recorded individual locations of adults and pre-fledge chicks to evaluate effects of post-Hurricane Sandy landscape features on resource selection of adults and chicks, and behavior and survival of plover broods. We evaluated whether breeding stage (pre-breeding, nesting, brooding, post-breeding), simple breeding stage (breeding, not-breeding), or instantaneous behavior class (parental, non-parental) best explained habitat selection during the 5-month plover breeding season. We also evaluated the effects of post-Hurricane Sandy landscape features on resource selection, behavior, and survival of plover broods during 2013–2019. We observed positive population growth in three of five years and overall growth through the study (λ ̅=1.12). Immigration and reproductive output were correlated with population growth (r = 0.93 and 0.74, respectively). Compared to the rest of the study area, restoration areas had higher chick survival but lower nest survival and breeding fidelity, and population growth (λ ̅=1.09) in restoration areas was similar. For adult plovers, behavior class best explained habitat selection. Compared to non-parental plovers, plovers engaged in parental behavior (incubating, brooding, and accompanying chicks, hereafter 'parental') selected areas closer to bay intertidal habitats and with more dry sand. Non-parental plovers avoided areas with more dry sand and did not select for or against bay intertidal habitats. Additionally, non-parental plovers avoided development more than parental plovers and avoided areas of lower elevation more than parental plovers. In each year, there was more suitable habitat for parental plovers than non-parental plovers. Plover broods selected for flatter sites with less vegetation but selected for sites closer to development as time since Hurricane Sandy increased. Chick foraging rates were highest in moist substrates and were negatively influenced by nesting plover density. Chick survival was negatively influenced by nesting plover density and was greater for earlier hatched broods. Further, chick survival was higher following an outbreak of sarcoptic mange in the local red fox (Vulpes vulpes) population. If human interventions were reduced or modified in such a way as to create, maintain, and improve habitat, plover populations likely would reach higher numbers, and the potential for achieving recovery goals would be increased. Future restoration areas projects could use Great Gun as a model, although design criteria could be improved to increase access to moist, flat, low energy foraging sites. Efforts to increase immigration of novel breeding adults into the system, primarily by habitat creation or maintenance, are likely to have the greatest local effect on population growth but may not improve regional population persistence if habitat creation is only local. Management to improve reproductive output is likely to have a positive effect on population growth if there is suitable habitat to support recruits and will improve regional population persistence by producing emigrants. When improving or creating plover habitat, managers should consider habitat needs both for plovers of all life stages. Habitat management should focus on maintaining vegetation-free sand and access to low-elevation foraging habitat. Allowing hurricanes such as Hurricane Sandy to alter the landscape naturally will create these landscape features. / Doctor of Philosophy / Piping plovers (Charadrius melodus) are federally threatened and endangered shorebirds that nest on sandy beaches, sandbars, and lakeshores. In October 2012, Hurricane Sandy created substantial habitat on Fire Island and Westhampton Island, New York, which could have acted as plover habitat. However, concerns about mainland safety from future storms prompted an island-wide project, building dunes planted with beach grass, to improve ability of Fire Island to protect the mainland. However, planted dunes had the potential to negatively affect newly created habitat, and certain sections of Fire Island were designed to create plover nesting habitat. Because of the habitat creation, we predicted that the population would increase. To illustrate that habitat creating events lead to plover population increases, we used freely available aerial imagery and identified all areas of dry and moist sand in study areas. We then used local plover monitoring data to relate habitat change to plover population change, and found that for several hurricanes and floods in the piping plover range, habitat increases led to population increase. We then evaluated population change on Fire Island and Westhampton Island, and found that the population increased 90% following Hurricane Sandy, and the increase was primarily due to new immigrant adults, and local reproductive success. The created restoration areas had similar reproductive output and population growth to the rest of the study area. To determine the areas on Fire Island and Westhampton Island that were adequate habitat for piping plover adults, we compared habitat used by plovers to what was available on the island and determined that habitat use differed between adults exhibiting parental behaviors and adults exhibiting all other behaviors. Non-parental plovers avoided dry sand. Both parental and non-parental plovers avoided development and high elevation sites. Overall, more sand was suitable for parental plovers than non-parental plovers. Because reproductive output also was influential to the population increase on Fire Island, we evaluated effects of landscape features on plover chick habitat, foraging, and survival. Plover chicks avoided vegetation, and selected flatter areas, but selected sites closer to development as time since Hurricane Sandy increased. Chicks spent more time foraging in moist substrates, and less time foraging when there were more plovers nesting in a management unit. Chick survival also was lower when more plovers were nesting in a management unit and was greater for earlier hatched broods. Further, chick survival was higher following a sharp decline in the local red fox (Vulpes vulpes) population. Overall, Hurricane Sandy was a positive force for this local plover population and local efforts to allow hurricane storm surges to modify the island in the future will improve long-term population persistence. Efforts to increase immigration of novel adults into Fire Island and Westhampton Island, primarily by habitat creation or maintenance, are likely to have the greatest local effect on positive population growth. Improving reproductive output is likely to have a positive effect on local and regional population growth, particularly by maintaining a low red fox population, if there is suitable habitat to support recruits. When improving or creating plover habitat, managers should consider habitat needs for plovers across the whole breeding season rather than just nesting. Habitat management should focus on maintaining vegetation-free sand, and access to low-elevation, flat foraging habitat. Habitat creation also may increase habitat amount and therefore local population growth.
8

Optimising habitat creation for woodland birds : the relative importance of local vs landscape scales

Whytock, Robin C. January 2018 (has links)
Global land-use change and industrialisation has driven biodiversity declines and impaired ecosystem functioning. Recently, there have been large-scale efforts to not only halt habitat loss but create and restore habitat on formerly managed (e.g. agricultural) land. However, although the effects of habitat loss and fragmentation on biodiversity are well understood, our understanding of how biodiversity responds to habitat created in a patchy configuration is not. In particular, little is known about the relative importance of local (e.g. patch size) vs landscape scales (e.g. amount of habitat in the landscape) for restoring biodiversity in created habitat. Here, a long-term, large-scale natural experiment (the Woodland Creation and Ecological Networks project) was used to understand how bird species, communities and behaviour respond to woodland created in a patchy configuration on post-agricultural land. I used a combination of direct and indirect survey methods to quantify bird diversity, abundance and vocal behaviour in post-agricultural woodlands of known age in Great Britain. I show that secondary woodlands favour generalist species and older patches contain more individuals and species due to their vegetation structure. In relative terms, local-scale factors such as patch size made the greatest contribution to bird diversity and abundance. Colonisation events drive community assembly in new habitat, and I found that large-scale (km2) habitat patterns were more important than patch-level factors during colonisation of breeding territories by a long distance migrant bird (Willow Warbler Phylloscopus trochilus). Land management practices surrounding a habitat patch can also affect its perceived quality and relative attractiveness to potential colonisers. Using the Eurasian Wren Troglodytes troglodytes as a model species, I found that high proportions of agricultural land at woodland edges caused an increase in perceived predation risk. In conclusion, I suggest that post-agricultural woodlands rapidly provide valuable habitat for generalist woodland birds. Local, patch-level factors (area, vegetation structure) also appear relatively more important than landscape factors for woodland bird communities. Land-managers seeking to maximise the benefits of woodland creation for birds should thus focus on creating large patches with a diverse vegetation structure.
9

Management and Mother Nature: piping plover demography and condition in response to flooding on the Missouri River

Hunt, Kelsi L. 17 November 2016 (has links)
Globally, riparian ecosystems are in decline due to anthropogenic modifications including damming, channelization and the conversion of the floodplain for human use. These changes can profoundly affect riparian species as many have adapted to the historical dynamism of these ecosystems. On the managed Missouri River, an imperiled shorebird, the piping plover (Charadrius melodus) uses riverine sandbars to breed. From 2004 to 2009, due to limited breeding habitat and low population numbers, the U.S. Army Corps of Engineers constructed 255 ha of sandbar habitat to benefit piping plovers and least terns (Sternula antillarum). During the breeding seasons of 2010 and 2011, historically high flows resulted in the creation of 1,887 ha of suitable sandbar habitat. Our study compared the demographic response and the condition of piping plovers to these anthropogenic and natural habitat creation events. From 2005–2014 we monitored 1,071 nests, and from those nests we uniquely banded 968 adults and 2,021 piping plover chicks. We obtained 405 egg (clutch) mass measurements, 1,285 mass measurements from 633 adults, and 7,093 mass measurements from 1,996 plover chicks resulting in 3,175 mass measurements from 654 broods of chicks. We also collected 3,347 invertebrate prey samples. We used a random effects logistic exposure model to estimate nest success, a random effects Cormack-Jolly-Seber model in RMARK to estimate pre-fledge chick survival and the Barker model in RMARK to estimate hatch-year (HY) and after hatch-year (AHY) survival and fidelity to our study area. We then used estimates from these analyses to calculate reproductive output, reproductive output necessary for a stationary population, and population growth (λ). For adult condition and egg (clutch) mass we used generalized linear mixed regression, and for pre-fledge chick growth rates we used a modified Richard's model to estimate the effects of habitat type (pre- vs. post-flood). We also tested for differences in invertebrate prey abundance between habitat types using negative binomial regression. Our results indicated that AHY survival varied throughout our study and was lowest during the flood (2010 and 2011). We found that nest success, pre-fledge chick survival, reproductive output, and HY survival and fidelity were consistently higher on the flood-created habitat than engineered habitat, leading to sustained population growth after the flooding, as compared to just one year of population growth prior to the flood. Unlike pre-flood engineered habitat, the demographic parameters we measured did not decrease as the post-flood habitat aged. These differences were related to increased sandbar habitat, low nesting densities, and decreased nest and chick predation on the post-flood habitat. Although we hypothesized that increased demographic rates would be reflected by increased piping plover condition following the flood, we found that our measured condition variables (adult mass, clutch mass, and pre-fledge chick growth rates) remained unchanged following the flood. We also found evidence that clutch mass, chick growth rates and invertebrate prey abundance decreased as the post-flood sandbar habitat aged. As the condition of individuals did not appear to contribute directly to the increased demographic rates following the flood, we suggest that the change in density-dependent predation pressure may explain the discrepancy. As many ecosystems have previously been altered, it's rare that ecologists have the opportunity to compare management practices with natural ecosystem processes. Results from this study suggest that management intervention may not be an equivalent substitute for natural ecosystem processes and provide insight on future management of riparian ecosystem. / Master of Science

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