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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.
21

Fire, seasonally dry evergreen forest and conservation, Huai Kha Khaeng Wildlife Sanctuary, Thailand

Johnson, Laura Anne 21 July 2006 (has links)
In recent years landscape-scale fires have occurred in mainland Southeast Asia, including important protected areas (PAs). There has been increasing concern that landscape-scale fires are degrading the seasonally dry evergreen forest (SEF) element of the forest mosaic to more open deciduous forest and savanna, with serious implications for biodiversity conservation. Present management approaches, including fire suppression and prescribed burning, have not been effective managing for landscape-scale fire. Research was undertaken to investigate the occurrence, cause, effect, frequency and predictability of fire in SEF. SEF has the greatest species biodiversity in the forest mosaic and is potentially the most affected by fire, yet little research has been done on fire in SEF in mainland Southeast Asia. Huai Kha Khaeng (HKK) Wildlife Sanctuary in Thailand was selected as the study area. The objectives included: 1) investigate the area of SEF burned in HKK from 1988 to 2002; 2) investigate the conditions for fire in SEF; 3) determine whether the area of SEF in HKK declined as a result of fire; 4) determine the frequency of fire season years between 1984 and 2001 with the conditions for fire spread in SEF; and 5) determine whether there is a significant relationship between pre-fire season drought codes (Keetch-Byram Drought Index (KBDI) and Canadian Drought Code (DC)) and identified SEF fire season years for 1981 to 2003. Methods included: development of a Landsat fire history with associated interviews and reconnaissance field checks; fieldwork lighting test fires and measuring fuel characteristics; remote sensing change detection work using Landsat imagery; generation of a twenty-one year daily relative humidity minimum record for SEF; and logistic regression of the pre-fire season drought code values with identified SEF ‘fire’ and ‘non-fire’ years. Results showed: 1. Extensive areas of SEF have burned, but that Landsat imagery was not suitable for detecting fire in intact SEF. 2. SEF burned in years when there were fires burning adjacent to SEF in mid March and the moisture content of the SEF leaf litter fuel was less than 15%. 3. Fifteen percent of SEF in HKK has been either degraded or converted to deciduous forest forms in 12 years. 4. Conditions for fire spread in SEF occurred four times in 17 consecutive years. 5. A significant relationship exists between both the Keetch-Byram Drought Code (KBDI) and Canadian Drought Code (DC) and the SEF fire years. Implications are that large-scale fires have adversely affected intact SEF in HKK, and that the current damaging situation can be expected to continue. Whereas the extent of burning in intact SEF is not known, the need to manage the situation is immediate. Landscape-scale fires in HKK can be managed by using January 31st drought code values to predict potential large-scale fire years, followed by an aggressive fire suppression campaign in those years. In other years, fires can be allowed to burn without serious threat to the forest mosaic, and should to some extent be encouraged to maintain open deciduous forests and savanna. Additional research is required to determine whether a similar approach can be used for protected areas in other parts of the region.
22

Svobodný software a spolupráce jako směr rozvoje českého knihovnictví / Free Software and Cooperation as a Course for Development of Czech Librarianship

Jansa, Václav January 2019 (has links)
The dissertation focuses on the use of free software in Czech libraries. Both real practice and librarians' attitudes to this type of software are analyzed. The main goal of the dissertation has been to evaluate the attitudes of Czech libraries to free software, to analyze its use in practice, to design information and communications strategy for free software project and to implement it using Evergreen as an example project. In order to achieve the goals, both qualitative and quantitative research methods have been used. These included a survey, web data gathering and analysis and also case studies. The devised and implemented information and communications strategy consists of eight main parts (setting up a local community, creating communication tools, organizing seminars, Czech localization, the creation of first common catalogues, making documentation publicly available, active involvement in the international community and establishing a legal entity to improve awareness about free software among librarians) which are complemented with a SWOT analysis evaluating the strategy implementation.
23

Increasing new member involvement in prayer ministry

Hoyt, Michael C. January 2005 (has links)
Thesis (D. Min.)--Midwestern Baptist Theological Seminary, 2005. / Abstract. Includes bibliographical references (leaves 304-310)
24

Implementing an [sic] new member assimilation strategy for Evergreen Park Baptist Church

Crawford, Philip C. January 2003 (has links) (PDF)
Thesis (D. Min.)--Mid-America Baptist Theological Seminary, 2003. / Includes bibliographical references (leaves 111-117).
25

Implementing an [sic] new member assimilation strategy for Evergreen Park Baptist Church

Crawford, Philip C. January 2003 (has links)
Thesis (D. Min.)--Mid-America Baptist Theological Seminary, 2003. / Includes bibliographical references (leaves 111-117).
26

Implementing an [sic] new member assimilation strategy for Evergreen Park Baptist Church

Crawford, Philip C. January 2003 (has links)
Thesis (D. Min.)--Mid-America Baptist Theological Seminary, 2003. / Includes bibliographical references (leaves 111-117).
27

Lignin is a good predictor of resistance species to water stress? / Lignina à um bom preditor da resistÃncia de espÃcies ao estresse hÃdrico?

Taysla Roberta Almeida de Lima 26 February 2015 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Tropical plant species resist seasonal drought by avoidance or tolerance, keeping or losing leaves, respectively. Since drought resistance is influenced by wood attributes and lignin is a major component of wood, we investigated whether lignin is related to foliar retention time (LR). We selected 22 species, determined the stem lignin content by thioglycolic acid and quantified guaiacyl (G) and syringyl (S) monomers by thioacidolysis and GC-MS analysis. Among these species, we selected 15 species to measure vulnerability to embolism by pneumatic method. In our analyses, were considered measures of wood density, stem water saturation and stem water potential in the dry season, published by other authors. Our analyses showed that there are two ways of surviving drought. A small group of species, for which the lignin does not seem to matter, stores water in the stem and loses leaves right at the end of the rainy season. A large group of species, from early deciduous to evergreens, retains leaves in the dry season for increasingly longer periods the higher the S/G ratio is. Higher values of the S/G ratio allow greater LR by reducing vulnerability to embolism. / EspÃcies de plantas de clima tropical sazonalmente resistem à seca por tolerÃncia ou evitaÃÃo, mantendo ou perdendo folhas, respectivamente. Atributos da madeira estÃo relacionados à resistÃncia à seca e a lignina à um dos principais componentes da madeira. Investigamos se a lignina està relacionada ao tempo de retenÃÃo foliar (LR). Selecionamos 22 espÃcies, determinamos o teor de lignina do caule pelo Ãcido tioglicÃlico e quantificamos os monÃmeros guaiacil (G) e siringil (S) by thioacidolysis e GC-MS analysis. Dentre as espÃcies, selecionamos 15 espÃcies para medir a vulnerabilidade ao embolismo pelo mÃtodo pneumÃtico. IncluÃmos medidas da densidade da madeira, saturaÃÃo de Ãgua no caule e potencial hÃdrico do caule na estaÃÃo seca, publicadas por outros autores. Nossas anÃlises mostraram haver duas maneiras de sobreviver à seca. Um pequeno grupo de espÃcies, para as quais a lignina parece nÃo ter importÃncia, armazena Ãgua no caule e perde folhas logo no final da estaÃÃo chuvosa. Um grande grupo de espÃcies, que vÃo desde decÃduas precoces atà sempre verdes, retÃm folhas na estaÃÃo seca por tempos cada vez mais longos quanto maior a razÃo S/G. Maiores valores da razÃo S/G permitem maior LR por diminuir a vulnerabilidade ao embolismo.
28

Vliv stálezelenosti vs. opadavosti u rostlin v teplých obdobích vyšších zeměpisných šířek na strukturu dřeva: případová studie ze svrchní křídy ostrova James Ross (Antarktický poloostrov) / Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)

Chernomorets, Oleksandra January 2019 (has links)
Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...
29

Vliv stálezelenosti vs. opadavosti u rostlin v teplých obdobích vyšších zeměpisných šířek na strukturu dřeva: případová studie ze svrchní křídy ostrova James Ross (Antarktický poloostrov) / Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)

Chernomorets, Oleksandra January 2019 (has links)
Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...
30

Species Ranges, Richness and Replacement of Trees in the Evergreen Forests of the Western Ghats

Page, Navendu January 2015 (has links) (PDF)
It has been more than two centuries since the latitudinal pattern of increase in taxonomic richness from poles to equator was first documented. After two centuries of research, and with more than two dozen hypotheses proposed, an understanding of the mechanisms underlying this pattern and their relative importance remains incomplete. Factors such as evolutionary history, area and latitude associated variables such as temperature, solar energy, climatic stability and seasonality are known to influence species richness by affecting geographic range size and location over ecological and evolutionary time. Understanding the forces that affect geographic range size is, therefore, integral to our understanding of latitudinal patterns in species richness. Using woody plants as a study system, my dissertation deciphers the latitudinal pattern, if any, in species richness within the evergreen forests of the Western Ghats. These wet evergreen forests form an evolutionarily distinct biogeographic zone, which has remained isolated from its counterparts. This has resulted in a high percentage of endemism among the evergreen woody plants and, therefore, the global geographic ranges of most of these plants are restricted within the boundaries of the Western Ghats. The first main objective of this dissertation is to understand the determinants of geographic range size in the evergreen woody plants of the Western Ghats. Further, the Western Ghats are characterized by a sharp climatic gradient in temperature and rainfall seasonality that is not correlated with mean annual temperature or annual rainfall. This allows a direct test of the hypotheses and predictions that are based on climatic seasonality, without the confounding effect of other climatic correlates of latitude. Therefore, the second main objective of this dissertation is to understand the mechanisms underlying latitudinal patterns in species richness of evergreen woody plants in the Western Ghats. Regional species richness is an outcome of two factors- local species richness of each location within the region and turnover in species composition among the locations, which in turn are a result of patterns in range size, range location and range overlap. To address these two objectives, I first test the effect of climatic niche of a species in determining geographic range size and then examine the effect of latitude associated climatic seasonality on range location and range overlap. Next, I link the observed pattern in range geometry to latitudinal patterns in species turnover and finally to latitudinal patterns in species richness. While the first part of my dissertation study deals with factors that generate spatial variation in species richness, the second part deals with the factors underlying spatial variation in species composition. Environmental heterogeneity and dispersal are considered the most important determinants of species turnover i.e. change in species composition. However, their relative importance in structuring in diverse plant communities within tropical regions across different scales is poorly understood. Hence, the third objective of this dissertation is to understand the processes that influence change in species composition of woody plants within the Western Ghats. Geographic range size and population size are important attributes of species rarity, which are directly linked to their extinction risk. Hence, data on distribution and population status of species can help us focus our efforts on those species that require conservation attention. This is achieved through carrying out species threat assessments based on attributes such as range and population size and then assigning then to a threat category. A majority of species endemic to the Western Ghats have not yet been assessed, largely due to lack of data on their population and distribution status. Therefore, the fourth and the final part of my dissertation explores the application of information on species range size and abundance in prioritizing species for conservation. To address these objectives, I sampled the wet evergreen forests of the Western Ghats along a series of locations distributed across its entire latitudinal gradient. Based on 156 plots, covering a latitudinal gradient of more than 1200 km and comprising of more than 20,000 occurrence locations belonging to more than 450 species of woody plants, I derived quantitative estimates of latitudinal gradients in range size, local and regional richness as well as species turnover. I used a combination of statistical and simulation approaches to discern the mechanisms underlying large-scale pattern in species ranges, richness and turnover. My dissertation is structured as follows.

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