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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.
121

Highland cash crop development and biodiversity conservation : the Hmong in Northern Thailand

Tungittiplakorn, Waranoot 13 October 2017 (has links)
This study explores two interlinked aspects of human-environment relationship—cash crop development and biodiversity conservation—by examining the situations of the Hmong people, the largest traditional pioneer swidden group in the Thai highlands. Cash crop adoption among the Hmong have occurred in two main ways. The first involves the adoption of low-input upland crops and a shift to high-input vegetable crops. This pattern is found in the Lower North and spread to the Upper North, particularly in Tak, Phrae, Nan, Payao and Chiang Rai. The adoption is closely linked to the development of roads into the uplands and the diffusion of maize cultivation in the lowlands. The second pattern is a direct shift from opium to high-input crops, particularly cabbage. Large scale cabbage growing began in the early 1980s as a response to the demand for off-season vegetables. The most important driving factors behind cash crop adoption were the government poppy eradication activities, the contacts between market agents and the Hmong and the increased accessibility of Hmong villages. Adoption was facilitated by favourable market prices at the initial period and by the Hmong clan network. Each type of cash crops has had its particular effects on the Hmong socio-economy. Cut-flowers bring small but regular income into a household while cabbages bring a lump sum, a few times a year. Cabbage production induces high level of truck ownership leading to increased mobility, rapid diffusion of innovations, changing cultural values and increased uses of lowland services (such as health care, schools, market, etc.). Flower production, on the other hand, allows women to take active parts in marketing. The study also found a type of movement not discussed in earlier literature, the temporary migration of households or parts of households to take advantage of successful cash crop cultivation in other villages for a period of 1–2 years. The examination of four cash crops: opium, maize, cabbage and carnations shows that the Hmong have gradually shifted from land extensive to land intensive cash crops. This move to economize on land is, however, recompensed by the need for high inputs in agriculture. The more land intensive the crop is, the more fertilizers and pesticides are used. Comparisons between crops on three variables: population-land ratio, income and pesticide used per unit area, suggest that cut-flowers may be a superior crop, if measures to reduce pesticide uses can be found. Cash crop adoption affect the relationships between the people and wildlife in three ways. First, the labour-intensive nature of cash crop production prevents farmers from spending as much time in the forest as in the past. Second, cash crops provide incomes which allow the people to obtain meat from the market and thus reducing the needs for wild meat. Third, cash crop economy orients people toward the lowland, resulting in weakening traditional knowledge about wildlife behaviours, hunting or trapping. Most Hmong view hunting as a leisure activity, and some, particular women, see it as a waste of time. Reduced hunting, however, has not lessen the pressure on wildlife as the population of all species are reportedly declining. Many Hmong villages have rules against hunting some species, particularly gibbons. This rule is respected by most people but not all. Since the people do not feel that their livelihood is greatly affected by the disappearance of wildlife, the direct relationships between economic improvement and conservation is not clearly apparent. / Graduate
122

A sociological analysis of biodiversity management in Nigeria

Obayi, Bennycharles A January 2015 (has links)
The central thesis of this study addresses biodiversity challenges from a social relations perspective. This is viewed from the standpoint of enhancing sustainable bioresource-use systems from a behaviour change departure. The study reviewed the activities of organisations in Nigeria which focus on bioresource management. The review focused on how the organisations view, conceive and implement activities which aim to address biodiversity loss emphasising how these aspects inform the concept of programme design, planning and implementation. The strategies were weighed against theories and techniques in behaviour change. The study argues that it should be recognised that the challenges of biodiversity loss have a strong relationship with how a society is socially constructed, and that addressing the challenges will require a systematic approach aimed at social construction, using efficient techniques to ensure behaviour change. The objective of the study was to acquire insight on how programmes which aim at addressing biodiversity loss in Nigeria approached behaviour change towards sustainable bioresource-use practise. The study captured these insights in a set of themes which provided an improved analysis on the dynamics of behaviour change and biodiversity management in Nigeria as well as extrapolated these findings to articulate new ideas on how to address the challenges of biodiversity loss in Nigeria. Through analysing basic suppositions and exposing contradictions, social science disciplines examine the credibility of arguments and key concepts that commonly remain unquestioned. Based on this premise, critical assumptions on biodiversity management were challenged by the study. Furthermore, the study articulated questions which have been raised in recent years from a variety of social science perspectives on biodiversity management concerns. The study postulated the need for biodiversity management to be approached from a social-construct perspective in rethinking the discourse on unsustainable bioresource-use patterns. The thesis derives from an eco-sociology framework rooted in human interaction analysis, which is connected with approaches in the social science of functionalism and behaviourism. The concepts and ideas discussed in the thesis lay out the main dimensions relevant to the discourse on behaviour change-biodiversity management. The study’s conceptual and theoretical underpinning discussed biodiversity management concerns from a global context and narrowed the discussion down to country specific contexts. Within these contexts, the study discussed issues of policies, legal systems, political and social systems, practices and programme activities, as part of management concerns. The study compiled relevant views on conservation and protection practises which were in line with internationally accepted norms and practises on biodiversity management. It highlights the challenges of current practises which emphasise strengthening of legal frameworks, policies and practises, and which criminalise actions that contravene ideally-construed conservation precepts as best models of addressing biodiversity loss. It further discussed the emphasis placed on protected-area systems as the main model of biodiversity conservation and argued on the need to rethink the approach within the Nigerian context. The study articulates the role of sociology in ecological discourse and argues that although the knowledge gained by physical and biological sciences are essential in addressing ecological challenges, however, they are not sufficient to understand the driving forces underlying ecological challenges and the phenomenon fundamental to understanding trends and patterns of human factors in biodiversity loss. The study was explored within the methodological framework of phenomenology as the underpinning paradigm using a qualitative approach for analysis. The layouts of the thesis ensure that the research moves from theoretical and conceptual reflections to the actualities of lived realities and situated practices embedded in biodiversity management in Nigeria. The conceptual inclination for the theoretical base for the study analysis was postulated, which articulate the study’s scientific and empirical contributions. The survey method reflects exploratory analytical inquiry which supported the study’s methodological considerations. This was based on the specific data chosen for review, which was informed by the selected organisation’s application of social-construct concepts. Considered from a national perspective, the study assumed that issues of biodiversity management concerns were not to be separated from everyday social realities and the larger social challenges. In view of this consideration, the study analysis looked at historical, political and socio-economic backdrops in Nigeria, which reflected on bioresource-use practises. These are relevant to understand the dynamics and interplay of culture and values in bioresource-use patterns. The study builds on diverse arrays of global frameworks to integrate the major findings of the study. These were compared with related and different dimensions as well as existing theories of human-bioresource interactions. The first aspect of the empirical analysis explored conceptual dimensions which raised questions concerning perceptions of reality and social values that were linked to the strategies of social-constructs expressed through policies, plans and practices. The study’s fundamental empirical dimension explored the forms in which programmes and social institutions were relevant in ensuring behaviour change towards sustainable bioresource-use practise. The analytical sequences observed trends which support facilitation of social change through behaviour change. Another aspect of the empirical analysis focused on revealing the processional dynamics of programme activities to achieve set objectives. This was analysed from the methodical perspective of how the processes were monitored and measured in order to achieve anticipated outcomes. The study summarised the findings and the outcomes by outlining the themes which emerged from the research. The study analysis argued that the ideals of social interventions cannot be different from a society’s inherent and attributed meanings to realities, as well as how they engage with their everyday realities.
123

Biodiversity Patterns on an Inshore to Offshore Gradient Using Metabarcoding and Barcoding Molecular Tools

Villalobos Vazquez de la Parra, Rodrigo 12 1900 (has links)
It has been estimated that coral reefs shelter 830 000 species. Well-studied biodiversity patterns provide tools for better representation of species in marine protected areas. A cross-shelf gradient in biodiversity exists for fishes, corals, and macroalgae. Here, an inshore to offshore gradient in biodiversity on the Saudi Arabian coast of the Red Sea was sampled using Autonomous Reef Monitoring Structures (ARMS) with barcoding and metabarcoding techniques. It was hypothesized that differences in community structure would be driven by an increase in habitat area. The difference was attributed to the greater accumulation of sediments close to shore that increases the area habitable for sediment dwelling organisms and favors macroalgal cover. Macroalgae are inhabited by a greater number of species than live coral. Only 10% of the sequences of the barcoded fraction and <1% of the metabarcoded fraction had a BLAST hit on the NCBI database with a previously identified species sequence. In addition, the rarefaction curves for all fractions did not plateau. The ARMS community composition changed from inshore to offshore and was significantly correlated with the percentage of algal and bryozoan plate cover. The differences in community composition were related to changes in habitat but not to sediments retrieved from the ARMS.
124

Birds in the City : Bird biodiversity in a boreal northern urban environment

Eriksson Reuterborg, Izabel January 2022 (has links)
Urbanization is a growing threat to biodiversity across the globe. As more and more habitats are being destroyed and species extinction rates are rising, we have started looking at how we might decrease this loss of biodiversity. One answer is changing our urban environments to more biodiversity friendly ones. Since conditions within a city and a natural landscape might differ, it is important to understand how landscape variables affect biodiversity in urban areas. The purpose of this study was to investigate how landscape variables (Coniferous/mixed forest, Open uncultivated land, Fields, Deciduous forest, Water, High and Low urban development, and Industrial area) affect bird diversity, richness, and community assembly in a small city in central Sweden. Surveys were conducted on 33 sites. Results from a multiple regression comparing the environmental variables to richness or diversity showed that Water was positively correlated to both diversity and richness. A redundancy analysis (RDA) showed that bird species assemblage was significantly affected by Coniferous/mixed forest, Water, and Fields when the whole bird community was considered. However, when only passerines were included in the RDA, Urban development and Coniferous/mixed forest had the strongest impact. When conservation efforts are made in urban areas, these variables need to be considered since they are correlated with different species and they might not be the same ones that are associated with richness or diversity of birds.
125

PERCEPTIONS AND KNOWLEDGE OF A SELECTED GROUP OF ORGANIC CONSUMERS IN BLOEMFONTEIN, FREE STATE PROVINCE

Hurndall, L, Wolmarans, J.L., Hattingh, Z January 2014 (has links)
Published Article / Organic agriculture is a production method that upholds the well-being of soil, ecosystems and people. It relies on ecological processes, biodiversity and cycles tailored to local conditions. This descriptive study assessed the knowledge and perceptions of organic food consumers in Bloemfontein. A convenience sample of 60 consumers (male and female) was selected to participate in the study. A structured questionnaire was designed to obtain data at a local fresh-produce grocer. Most of the consumers showed positive and negative attitudes towards organic products. Most consumers had basic knowledge regarding organic products, but it also became evident that there was uncertainty surrounding facts of organic products, such as labelling standards. Only 12% of respondents interpreted the term “organic” correctly. Human health (86.67%) and environmental concerns (28.33%) were the key factors influencing consumer preference for organic food. Organic fruit and vegetables (45.37%) were the most popular purchased organic items amongst consumers. The majority of consumers (61.67%) stated that organic products are affordable. The results of the present study provided valuable insight into the knowledge, perceptions and attitudes of consumers towards organically grown foods. The general positive attitude of consumers can be attributed to consumers' basic knowledge of, and preference for, organic food. Despite the organic lifestyle being in the minority in this region, there continues to be a growing demand for organic products in Bloemfontein, and for this reason producers have ensured a continued supply of organic products.
126

Biodiversity, ecology and taxonomy of saprobic fungi on palm fronds

鄭遠技, Yanna. January 2001 (has links)
published_or_final_version / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
127

Improving environmental sustainability in Hong Kong: the role of biodiversity

張芝明, Cheung, chi-ming. January 2002 (has links)
published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning
128

The effects of forest fragmentation on stream invertebrate communities on Banks Peninsula

Fraser, Iain January 2006 (has links)
The removal of indigenous forest and associated fragmentation of habitats has probably had significant impacts on the diversity of stream communities in New Zealand. In this study I investigated the effects of forest fragmentation on stream invertebrate communities on Banks Peninsula. Six catchments were investigated, three with continuous indigenous forest in the riparian zone and three with fragmented indigenous riparian forest. An extensive benthic survey was conducted at three sites in each river catchment, one downstream on the mainstem of the river and two sites in different headwater tributaries. Adult sampling, consisting of malaise and sticky trapping, was also conducted at a sub-set of sites. Taxonomic richness of both the benthic and adult communities was significantly higher in continuous forest than in fragmented forest, and the composition of benthic communities also differed between continuous and forest fragments. Furthermore, benthic invertebrate densities were higher in fragments than continuous forest sites. The fragments in the headwaters were more likely to support forest specialist taxa (e.g. the stonefly Zelandobius wardi, and the caddisfly Costachorema peninsulae), than the downstream fragments. My results indicate that forest fragmentation has resulted in marked changes in benthic communities on Banks Peninsula, and that location of the fragment within the catchment also is important in influencing the diversity and composition of benthic communities. The maintenance of indigenous forest in the headwaters of streams may be essential for the persistence of endemic and forest specialist taxa on Banks Peninsula.
129

The ecology and management of the lesser Indian mongoose Herpestes javanicus on Mauritius

Roy, Sugoto Solomon January 2001 (has links)
No description available.
130

Broad-leaved tree and shrub invasion of conifer plantations in Ireland

Blackstock, Philip January 1998 (has links)
No description available.

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