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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

How conservation has changed from 1975 to 2005

McBride, Patrick January 2015 (has links)
The aim of this thesis is to examine the nature of the changes that took place within paper conservation, a section of the practice/occupation of material conservation, in the United Kingdom during the period from 1975 to 2005. In the 1970s, conservation emerged as a distinct practice within the museum sector from two sources: semi-skilled cleaners and movers of art objects, and the traditional restorers of cultural objects. From then until the end of the century, it continued to grow and mature. The nature of this growth and the changes that took place within it will be modelled with the objective of enabling future changes within conservation to be evaluated. The evaluation of conservation in this manner will determine its definition as an industry. The changes will be assessed by highlighting their effect on one section of conservation practice, namely paper conservation. This practice concentrates on the conservation of cultural material created using paper, including such categories of artefacts as watercolours, fine art prints, drawings, ephemera, archival materials, books and all paper-based sculpture. During the period between 1970 and 2000, paper conservation developed from being a fledgling practice to becoming an accepted standard within the museum sector. In becoming so, it placed great emphasis on professionalism. This provided paper conservation with a template for change, a process through which it could develop and grow. Paper conservation embraced this process as a means of providing a set of standards to which it could adhere, but also as a means of garnering greater acceptability for its approach within the wider museum sector. Issues relating to the development of a profession and professionalism will be further explored as part of the literature review. Organisational change was also considered to have a relevance to the development of paper conservation, and this, too, will be explored within the literature review. Steps to professionalise conservation and subsequent changes in the wider museum sector were seen to have had the most impact on the structure of conservation. They may also have had relevance for the practice itself. Paper conservation was successful in having its occupational aims accepted throughout the museum sector, and this has further implications for those interested in researching by occupations of the professionalisation process. An understanding of the nature of this change, and how paper conservation reached its goal of acceptance for its values, is indispensable for those involved in decision-making within conservation today, and in the future. The thesis is based on an analysis of documents from the period directly relating to change within the field of conservation. It also includes interviews with personnel who were practising conservators, the providers of conservation education, and officers of the different agencies representing conservation. Research questions were formed from this analysis, and multiple case studies were undertaken to analyse these questions.
2

Prioritizing private land for conservation easement riparian corridor conservation along the West Gallatin River /

Holscher, Erik Edward. January 2005 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Kathy Hansen. Includes bibliographical references (leaves 57-61).
3

Die Sanierung von Biodiversitätsschäden nach der europäischen Umwelthaftungsrichtlinie

Kiess, Carolin. January 2008 (has links)
Thesis (doctoral)--Universität Mannheim, 2007. / Description based on print version record. Includes bibliographical references (p. [219]-230) and subject index.
4

Habitat loss and fragmentation on the Palouse and its impact on arthropod conservation /

Looney, Chris. January 1900 (has links)
Thesis (Ph. D., Environmental Science)--University of Idaho, June 2008. / Major professor: Sanford D. Eigenbrode. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
5

Soil and water conservation programs in action the Vernon County Wisconsin experience /

Goto, Junko. January 1981 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 167-176).
6

Assessing the conservation status of neotropical dry forests using geographical information systems and optical remote sensing

Portillo, Carlos Alonso. January 2010 (has links)
Thesis (Ph.D.)--University of Alberta, 2010. / Title from PDF file main screen (viewed on July 13, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Earth and Atmospheric Sciences, University of Alberta. Includes bibliographical references.
7

Soil and water management systems for two selected regions of the Jos Plateau, Nigeria

Ogunlana, Francis Afolabi. January 1977 (has links)
Thesis--Wisconsin. / Includes bibliographical references (leaves 103-107).
8

An Evaluation of New England Cottontail Habitat Restoration

Warren, Alena 14 March 2018 (has links)
<p> Several state, federal and non-profit agencies have developed collaborative goals for restoring habitat in New England and New York for a declining rabbit species, the New England cottontail (<i>Sylvilagus transitionalis</i>, NEC). My goal was to evaluate habitat restorations at both the local, or site, scale, and the landscape scale. In order to objectively quantify the suitability of the sites being managed, I developed a Habitat Suitability Index, based on the HSI models designed the U.S. Fish and Wildlife Service. I identified candidate habitat variables for NEC, including types of cover and refuges, and food, and then asked a panel of NEC experts to rank the importance of the candidate variables. I collected data on the most important habitat variables at 60 sites managed for NEC across New England and eastern New York. The NEC experts also ranked the same 60 sites from 1 (unsuitable) to 5 (optimal). The model was optimized to improve agreement with expert opinions for the 60 sites. Specific applications may include determining when a site is suitable for releasing translocated or captive breed rabbits, and identifying habitat features that need modification as forest succession progresses. To evaluate habitat restoration efforts at a larger landscape scale, I created metapopulation models for two management focus areas (Cape Elizabeth and Kittery-Berwick) in Maine for population viability analyses. I ran simulations to compare the relative effects of the two focus areas as well as five management scenarios. I conducted a sensitivity analysis to determine the importance of various model parameters on extinction risk. The Cape Elizabeth focus area, which has more habitat patches that are closer together, had lower extinction risks than Kittery-Berwick. Reintroductions and creating additional habitat appeared especially important in the Kittery-Berwick focus area. The simulation results were sensitive to changes in the standard deviations of the survival and recruitment rates, and the probability of catastrophic mortality, indicating that variation is detrimental to NEC metapopulation growth. Variation in weather caused by climate change may need to be mitigated by monitoring and managing NEC habitat and populations.</p><p>
9

Current status and impact (2004-2015) of indigenous ungulate herbivory on the vegetation of Sanbona Wildlife Reserve in the Little Karoo

Vorster, Liesl January 2017 (has links)
Game farming is becoming more popular in southern Africa and the introduction of large indigenous ungulates into confined enclosed areas could alter plant communities and ecosystem processes. This is of particular concern in semi-arid rangelands of the Succulent Karoo where the evolutionary history of grazing is not clear and the compatibility of large herbivores in confined areas remains to be demonstrated. The establishment of Sanbona Wildlife Reserve, a 54 000 hectare private game reserve in the Little Karoo, which converted from livestock farming to game farming, allows an opportunity to study the vegetation dynamics in a confined plant-herbivore system. This study investigates the current community structure and the changes in the floral composition and vegetation structure of enclosed and comparable sites subjected to grazing by large herbivores after twelve years (2004-2015). It also determines the relative effect of grazing and rainfall on the observed patterns. Finally, the implications of these findings for management are discussed. Data from drop-point surveys in fenced (exclosure) and unfenced (grazed) plots in the dominant vegetation types as well as annual and seasonal rainfall totals, stocking rates of herbivores and annual game census information, were analysed. These were used in multivariate ordination techniques, regressions and linear mixed-effects models to determine the communities and their relationship with herbivory and rainfall over time and identify a set of indicator species. The annual game census information was used to determine areas of herbivore preference or 'hotspots' and for the identification of highly-utilised areas. Cluster analysis, using the flexible beta method in PC-Ord, was used to determine the current plant communities. Non-metric multidimensional scaling ordination (NMS) was used to determine the relationship of these communities with the environmental variables and illustrate the trajectories in floristic data. Species were also assigned to plant growth forms and examined as communities and growth form types. The Bray-Curtis distance measures were used to investigate the difference between each treatment over time, within each vegetation community and between treatments. Finally, the effects of rainfall and herbivory were examined using linear mixed-effects models of change over time vs the various potential determinants of change using lmer functions in R. Four communities were identified. These communities corresponded well with to the vegetation type descriptions for Western Little Karoo, Little Karoo Quartz Vygieveld and Renosterveld as described in the National Vegetation Map of Mucina and Rutherford (2006). However, the Western Little Karoo was too broad and two communities were recognised within this vegetation type. The finer scale mapping by Vlok et al. (2005) corresponded relatively well to these communities. Results showed an increase in species richness, abundance and cover over time, with the ungrazed plots experiencing more change than the plots exposed to grazing. Most growth forms exhibited an increase in cover, although low leaf succulents declined in both grazed and ungrazed plots. Medium evergreen shrubs declined in the exclosures and stem succulents declined in the grazed plots. The effects were found in both grazed and ungrazed treatments. In addition, many species which declined in abundance were unpalatable or toxic to herbivores. Because of this, the decline in cover of such species was not attributed to grazing, but was instead interpreted as being a response to other disturbance mechanisms, to competitive displacement and to rainfall events. The low stocking rates in the first five years of the study resulted in there being very little difference evident between the treatments. However, once stocking rates increased from 2008, both species richness and cover increased more rapidly in the ungrazed plots, compared to the grazed plots. An increase in palatable and unpalatable species was observed within both ungrazed and grazed plots indicating that grazing did not change the proportion of palatability classes. However, specific plots in the areas of high animal utilisation were more affected as indicated by the response of cover, species richness and palatable species in these specific plots. This suggests that the grazing pressure may be too high within those areas. The linear mixed-effect model supports the argument that grazing pressure is the dominant driver of the community change within grazed plots. Similarly, the results show that rainfall is the primary driver of the vegetation community in the absence of grazing. Timing, amount and intensity of rainfall can mask these impacts. Thus, the contribution of grazing to vegetation change can probably only be detected by tracking the trends over decades or longer. The use of indicators as a management tool is well documented. In order to identify indicators, a theoretical framework for determining indicators species in the different vegetation communities was created. This was based on the correlation between species abundance and sampling period in the different treatments, which identified species that have significantly increased or decreased over time as a result of the change in land use. Species identified as potential indicators were selected on the basis based on their abundance and ranged in lifespans and palatability. The indicators chosen need to be monitored into the future to confirm their utility as indicators. A small but significant difference between grazed and ungrazed plots suggest that herbivore impact is apparent. Identifying this trend indicates that the monitoring programme is providing a useful tool for assessing the impact of herbivores on an ongoing basis. The recovery process following the withdrawal of domestic livestock from Sanbona was much slower in the grazed plots than in the protected plots. Therefore, for the continued recovery of the vegetation to occur and for there to be a sustained increase in cover, active management of animal numbers needs to take place. The results from this study can contribute to future management decisions on the reserve and form a basis for future analyses.
10

Conservation tillage systems and water productivity implications for smallholder farmers in semi-arid Ethiopia

Leye, Melesse Temesgen, January 1900 (has links)
Thesis (doctoral)--Delft University of Technology, 2007. / Vita. Includes bibliographical references (p. [99]-110).

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