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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.
81

Subalpine Wetlands characterization, environmental drivers, and response to human perturbation and restoration /

Heikes-Knapton, Sunni Marie. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Duncan T. Patten. Includes bibliographical references (leaves 122-131).
82

Incorporating uncertainty into freshwater habitat restoration /

Lando, Jody Brauner. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 81-98).
83

A diverse people how the leaders of the Restoration Movement view their own history and principles /

DeWelt, Christopher Don, January 1995 (has links)
Thesis (M.A.)--Cincinnati Bible College & Seminary, 1995. / "Perspectives from a survey of senior ministers of the Christian Churches/Churches of Christ conducted in November 1994 through February 1995." Includes abstract and vita. Includes bibliographical references (leaves 117-120).
84

Morphology of the interdental papillae during restorative dentistry procedures a photogrammetric method of investigation /

Pilot, Taeke. January 1972 (has links)
Thesis (doctoral)--Rijksuniversiteit te Utrecht. / "Appendix" (p. 45-76) inserted in pocket at end.
85

Morphology of the interdental papillae during restorative dentistry procedures a photogrammetric method of investigation /

Pilot, Taeke. January 1972 (has links)
Thesis (doctoral)--Rijksuniversiteit te Utrecht. / "Appendix" (p. 45-76) inserted in pocket at end.
86

Influence of stream corridor geomorphology on large wood jams and associated fish assemblages in mixed deciduous-conifer forest in Upper Michigan

Morris, Arthur E. L. January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xvi, 263 p.; also includes graphics (some col.). Includes bibliographical references (p. 241-263). Available online via OhioLINK's ETD Center
87

A cost-effectiveness analysis of Crassostrea virginica restoration as a possible nutrient reducing method within Chesapeake Bay a study of the Great Wicomico River, Virginia /

Wenczel, Amanda Ann. January 2007 (has links)
Thesis (M.M.P.)--University of Delaware, 2007. / Principal faculty advisor: George R. Parsons, College of Marine and Earth Studies. Includes bibliographical references.
88

Avaliação do potencial invasivo de espécies não-nativas utilizadas em plantio de restauração de matas ciliares

Assis, Geissianny Bessão de [UNESP] 27 January 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-27Bitstream added on 2014-06-13T19:18:59Z : No. of bitstreams: 1 assis_gb_me_botfca.pdf: 760870 bytes, checksum: abf315d42fc386ef18086a065996a436 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A restauração de ecossistemas vem ganhando espaço em todo o mundo e, no Brasil, o modelo mais amplamente utilizado tem sido o plantio de espécies arbóreas em alta diversidade. Embora a recomendação seja de que se utilizem exclusivamente espécies nativas, a dificuldade de identificá-las e de se encontrarem mudas disponíveis resulta que em muitos plantios existem espécies não-nativas, as quais oferecem a ameaça potencial de invasão biológica. O objetivo desta pesquisa foi analisar o potencial invasivo das espécies arbóreas não-nativas que têm sido plantadas para a restauração de matas ciliares em região de Floresta Estacional Semidecidual - FES, com base na estrutura de suas populações e em sua contribuição para as comunidades em restauração. Selecionamos 25 plantios de matas ciliares situados na bacia do rio Paraná, com idades variando entre quatro e 53 anos. Em cada local efetuamos o levantamento da comunidade arbustivo-arbórea em área total de 1.000 m2, dividida em 10 parcelas de 100 m2, aleatoriamente distribuídas dentro da faixa de 0 a 50 m de distância da margem do corpo d‟água. Identificamos e contabilizamos todos os indivíduos de espécies arbóreas e arbustivas, plantadas ou regenerantes, a partir de 50 cm de altura, agrupando-os em três classes de tamanho segundo o diâmetro à altura do peito (DAP < 1 cm, 1 cm < DAP < 5 cm e DAP > 5 cm). Classificamos os indivíduos em plantados ou regenerantes com base no alinhamento do plantio, evidente mesmo em plantios mais antigos. No total, amostramos 18.421 indivíduos, pertencentes a 320 espécies, das quais 83 (26%) não eram nativas da região estudada. Com relação à origem das espécies amostradas nos plantios, 65% são nativas de FES, 19% são nativas de outras formações vegetacionais brasileiras e 16% são... / The restoration of the ecosystems has been increasing worldwide. The most widely used model in Brazil has been the planting of the high diversity tree species. Although the recommendation it is planting only native species during restoration, the difficulty to identify them and to find seedlings available, result in many planting are found non-native species, which offer the potential threat of biological invasion. The purpose of this study was to analyze the potential of invasive non-native tree species that have been planted to riparian forests restoration in the region of semideciduous forest, based on the structure of their populations in regeneration. We selected 25 areas in restoration, of the aged between 4 and 53 years after planting. At each site we carried out the floristic inventory in the total area of 1.000 m2, divided into ten plots randomly distributed, within the range of 0 to 50 m away from the edge of the water body. Identify and account for individuals of all tree and shrub species present in the understory, from 50 cm tall, grouped into three size classes by diameter at breast height (DBH < 1 cm, 1 cm < DBH < 5 cm and DBH > 5 cm) . We classify the species planted and regenerating based on the alignment of planting, evident even in the oldest plantation. In total, 18.421 individuals sampled, belonging to 320 species. Regarding the origin of the species in plantations, 65% are native FES, 19% are of other native vegetation formations in Brazil and 16% are from other countries. Only three areas were not planted non-native species. In other areas, non-native species were used in varying proportions, to a maximum of 54% of all species sampled from planted trees in a community restoration. The proportion of individuals of non-native species from regenerating plants (12%) was lower than XIV the proportion... (Complete abstract click electronic access below)
89

Characterization of hydrology and water quality at a restored oxbow : ecosystem services achieved in year one

Haines, Bryce Jordan 15 December 2017 (has links)
Conservation practices are needed to reduce nitrate loss across the Midwest. Different riparian wetland designs have been investigated, but the physical, chemical and biological processes controlling nutrient cycling in restored oxbows are not well understood. A restored oxbow’s influence on nutrient cycling was investigated by studying the hydrogeology and water quality at a recently reconstructed oxbow site adjacent to Morgan Creek in Linn County, Iowa. Over a one-year period, the lentic oxbow’s nitrate loading was found to be dominated by flood pulses. Nitrate concentrations in the stream ranged from 7.38 – 12.95 mg l-1, concentrations were consistently low in the oxbow ranging from < 0.10 – 5.35 mg l-1, and the lowest nitrate concentrations were detected in the groundwater ranging from 0.10 to 3.4 mg l-1. Following a spring flood event, an in-situ sensor measured the nitrate concentration in the oxbow. Nitrate retention efficiency was estimated to be 0.30 g N m-2 d-1 or a 74.2% reduction efficiency. The observed nitrate reduction was compared to a first order denitrification model. The observed nitrate reduction measured in the oxbow followed a linear decay rather than an exponential decay suggested by first order kinetics.
90

Quantifying The Impacts Of Oyster Reef Restoration On Oyster Coverage, Wave Attenuation And Seagrass Fragment Retention In Mosquito Lagoon, Florida

Garvis, Stephanie 01 January 2012 (has links)
The goal of this project was to determine the effects of oyster reef restoration on oyster coverage, wave height dissipation and seagrass recruitment. First, to assess the current versus historical coverage of natural, dead and restored oyster reefs within Mosquito Lagoon, aerial photographs from 2009, provided by Saint Johns River Water Management District, were digitized using ArcGIS software. Live reefs, restored reefs and dead reefs were screen digitized using a reef ‘signature’ in order to estimate the area of each type of reef. The 2009 maps were used as a guide to digitizing the historical aerial photographs (1943, 1951, 1967, 1971, 1984, 1995, 2006). Dead reefs increased both in number and aerial extent during the study period (1943 – 2009), with 2009 having over 10 acres of dead reef coverage. Dead reefs were more likely to be found along major boating channels. Several dead reefs exhibited migration into the mangrove islands located landward of the 1943 footprint, with some dead reefs completely washing up into the shoreline. Restoration of dead reefs added 0.5 acres of live oysters to the Mosquito Lagoon area as of January 2009. Second, I examined how different oyster reef types (natural reef, restored reef, dead reef) reduced wave height. To determine wave height attenuation on each reef type, experiments were conducted in a 9 meter long wave tank using sensors that measured changes in wave height. For each reef type, replicate reefs were created in the wave tank. Shoreline sediment without oysters was used as a control. Using the wave generator, wave heights similar to Mosquito Lagoon boat wakes were created. Restored reefs reduced the incoming wave height by 25% compared to sediment without oysters. iii Lastly, I examined the potential link between oyster reef restoration and recruitment of seagrass fragments. Monthly surveys were performed to quantify the number of seagrass fragments encountering the three oyster reef types: dead reefs, natural reefs and restored reefs. The quantity of seagrass fragments was found to be similar on the three different reef types, but did show a significant trend of seasonality, which corresponds with the growing season of Halodule wrightii. Next, I tested retention of experimentally manipulated seagrass fragments on five natural and five restored reefs. Restored reefs retained seagrass fragments for significantly longer than natural reefs. I also measured seagrass fragment entanglement on each reef type inside the wave tank. I found that seagrass fragments were significantly more likely to become entangled and retained on restored reefs compared to dead and natural reefs. Overall, these metrics are important for determining the success of long-term oyster restoration project in Mosquito Lagoon, Florida. This project has found that oyster restoration is increasing the area of oyster habitat as well as providing important ecosystem services.

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