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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

Regeneration and succession following shifting cultivation and dry tropical deciduous forests of Sri Lanka

Perera, G. A. Dhammika January 1998 (has links)
No description available.
2

Approaches to Sustainable Forest Management in Parcelized Landscapes

Baumflek, Michelle 18 June 2008 (has links)
The holistic, landscape-based approach of Sustainable Forest Management (SFM) in the United States emphasizes the importance of addressing three components of forest management: ecology, community, and economy. Many believe this approach represents an important and positive paradigm shift in natural resource management. In Vermont, as well as many other parts of the United States, parcelized forest ownership presents challenges to the achievement of SFM on private property. These challenges include that of applying concepts of landscape-scale management over a mosaic of small landownerships while addressing ecological, economic, and social dynamics. Many authors have suggested a need for new institutions that are better capable of addressing the integrated, boundary-crossing nature of SFM on private lands. In Vermont, partnerships involving environmental non-profit organizations are implementing innovative management strategies to promote SFM which address the challenges of parcelization. In so doing, non-profit groups are branching out from traditional roles of advocacy and public goods protection to address not only the ecological, but also economic and community aspects of forest management. Examining the strategies, organizational roles, challenges and perceived permanence of these partnerships provides a greater understanding of the nature of these new institutional arrangements for SFM. This study asks the question: How do partnerships involving environmental nonprofit organizations in Vermont attempt to achieve goals of sustainable forest management in the context of a parcelized landscape? Using a multiple case study approach, I examine three SFM-related partnerships in Vermont that involve environmental nonprofit organizations. I assess their strategies, organizational roles, challenges and perceived permanence. Results indicate that partnerships involving environmental nonprofit organizations are playing important roles in defining and institutionalizing SFM in Vermont. Partnerships use diverse strategies through which they strive to account for the three components of SFM. I find three points of entry into SFM-related issues, connected to three strategies used by partnerships to address issues of parcelization: community-based, alternative silviculture and product branding. This diversity in approach may complement the diverse nature of forest landowner’s wants and needs. Furthermore, demonstrated flexibility at the partnership and organizational levels allowed partnerships to better work toward their goals. Challenges encountered by partnerships involved both internal dynamics and external circumstances, including differential organizational capacity and economic conditions, respectively. In addition, perceived permanence of these institutional arrangements may be related to the roles that environmental nonprofit organizations play within each partnership. Findings increase our understanding of the changing roles of non-profit organizations in the forest management sector, raise key questions about the permanence of such arrangements, and provide insights into partnership practices and challenges that may be applied in other settings. The results of this study contribute to a broader analysis of national trends in SFM.
3

Développement d'une sylviculture à vocation énergétique et conservation de la biodiversité saproxylique / Forestry development for energy and conservation of saproxylic biodiversity

Lassauce, Aurore 16 December 2011 (has links)
Pour répondre aux enjeux énergétiques et écologiques actuels, les pouvoirs publics prévoient une forte augmentation des prélèvements de bois à l'horizon 2020. Cependant, très peu d'études en milieu tempéré établissent clairement un lien entre les changements sylvicoles associés et la préservation de la biodiversité. L’enjeu de cette thèse est d’améliorer les connaissances sur lesquelles fonder des outils de conservation pertinents et favorables à la biodiversité, en adoptant les coléoptères saproxyliques comme modèle biologique. Le volume de bois mort a souvent été retenu comme un indicateur de gestion durable des forêts. Au travers d'une méta-analyse, nous avons cherché à appréhender son importance et ses limites en tant qu’indicateur de biodiversité. Nous montrons que toute augmentation du volume de bois mort est favorable à la biodiversité. Nous avons ensuite testé l'effet de la qualité de différents types de rémanents (essence, diamètre et stade de décomposition) sur la biodiversité afin d'identifier les principaux facteurs déterminant la composition des assemblages. Nos résultats montrent que les variables à l’échelle de la pièce de bois mort jouent un rôle important pour la biodiversité. Enfin, nous avons étudié la valeur écologique de zones abandonnées par la sylviculture(taillis-sous-futaie abandonnés depuis plus de 60 ans), et l'impact du raccourcissement ou de l'allongement de la durée de rotation en futaie régulière de chêne. Nous avons ainsi montré que les zones vieillies hébergent une plus grande biodiversité et que la diminution des rotations sylvicoles pourrait avoir un impact négatif. Par conséquent, la préservation des zones vieillissantes permettrait de favoriser la conservation de la biodiversité saproxylique.Cette étude est la première du genre en milieu tempéré. Malgré les résultats obtenus, de multiples questions se posent encore et de nombreux facteurs sont encore à étudier. / Facing current energetic and ecological issues, public authorities forecast a strong increase in wood harvesting by 2020. Nevertheless, in the temperate biome, very few studies clearly link sylviculture changes associated with such an increase and conservation of biodiversity. The main issue of this Phd thesis was to improve the knowledge on which managers could build relevant conservation tools to preserve biodiversity. For this purpose, we used saproxylic beetles as biological model. Deadwood volume has often been used as an indicator for sustainable forest management. Using meta-analysis, we tested the relevance of deadwood volume as biodiversity indicator. We showed that an increase in deadwood volume favours biodiversity, but this relationship remains weak for temperate forests. We then tested the effect of different logging residues qualities (tree species, diameter and decay class) on biodiversity in order to identify the main drivers of assemblages’ composition. Our results showed that piece of wood characteristics play an important role on biodiversity. Finally, we studied the ecological value of areas where management had been abandoned (coppices-with-standard where coppice had not been harvested for more than 60 years) and the influence of shortened or increased rotation lengths in oak high forest (160-300 years). We thus showed that overmature areas have higher levels of biodiversity and that shortened rotations lengths may have a negative impact on biodiversity. As a consequence, maintaining such overmature zones may help preserve saproxylic biodiversity. This study is the first to be conducted in the temperate biome. Despite the results obtained, many questions lay ahead and many factors remain to be studied.
4

Fire history, landscape biodiversity and indicators for sustainable management of the boreal mixedwood forest

Bergeron, Colin Unknown Date
No description available.
5

Learning for Sustainability through Community Forest Management

Assuah, Anderson 05 March 2015 (has links)
Community forestry is considered a collaborative governance approach that notionally provides local communities with some decision-making authority about forest management, as well as being promoted as a promising approach for ensuring forest sustainability and encouraging social learning among participants. Based on these potential benefits, this research investigated how collaboration and learning can help in managing community forests sustainably. The research involved a qualitative case study, focused on the Wetzinkwa Community Forest Corporation (WCFC) located in Smithers, British Columbia. Data were collected through semi-structured interviews with WCFC participants, forest tours, participant observation, and document review. The results indicate that individual and social learning did occur through collaborating on forest management issues such as sustainable forest management and benefit distribution. Further, the data shows the WCFC was making progress in sustainably managing the forest through efforts such as protecting forest under-story and embarking on a project to ensure forest health and resiliency.
6

Climate change mitigation through reduced-impact logging : a framework approach

Galante, Michael Victor January 2016 (has links)
The implementation of reduced-impact logging (RIL) in Sabah is recognised in the literature as an activity to reduce the environmental impact of timber harvest activities, thus reducing carbon entering the atmosphere. With the adoption of the Paris Agreement in 2015, modalities for its application as a project-based activity under the Climate Convention have yet to be developed. Investigations on both, its potential to reduce carbon from being released into the atmosphere in Sabah, specifically, and its modalities as a project-based activity under the Climate Convention in Malaysia, broadly, are warranted. This thesis addresses a set of research questions related to modalities for its inclusion under the Climate Convention, temporal and spatial responses of the forest after its implementation, to the investigation of activity-specific modalities, and their effectiveness, and its associated finance under the Climate Convention in Malaysia. The improvement of the forest activities under the Climate Convention are conceptualised through the Hierarchy of Production Forest Management (HoPFM), i.e., a modular framework defining the progression of the forest industry through demonstrable benefits. The conceptual framework begins from the basic legal and regulatory frameworks that govern forest management activities, towards sustainable forest management as the ideology of the Framework, designed to recognise both local, and global, approaches to forest management, while highlighting the need for balanced considerations of environmental, social and economic values. Through the Framework, the components of RIL in Sabah are discussed, relative to the modalities of the Climate Convention. Since he inception of the GIZ programme to improve forest management systems in the Deramakot forest reserve, there has been limited research on its recovery after RIL activities. Data on aboveground alive tree biomass and deadwood necromass was collected, and tested against 'harvest intensity', and 'time since harvest', to assess the temporal and spatial variability of forest responses, both within diameter classes, and major functional species classes of 'dipterocarp' and 'non-dipterocarp'. It was identified that 'harvest intensity' was found to be affecting forest recovery, relative to 'time since harvest', which was similarly identified for 'dipterocarp' species, relative to 'non-dipterocarp', respectively. The few significant changes detected indicate that long-term periods of analysis are required to identify consistent trends over-time. Since the mandate of the RIL policy in Sabah, conventional harvest activities are no longer eligible to be practiced in commercial production reserves. Therefore, to measure changes in carbon between the practices under the Climate Convention, a baseline needs to be developed, where conventional harvest activities were historically, the only form of harvest practice. An analysis of the literature was undertaken to estimate the difference between the practices, whereby broad impact classes of ‘infrastructure created’, and ‘harvest damage’, were identified. In its application, the ‘crediting’ approach is applied, whereby a benchmark is set, counterfactually, to estimate carbon that would be released without RIL activities. A number of carbon reductions are withheld from issuance into the market, to create a buffer between actually and potential issuance. The approach is conservative, to account for changes in policy and project-based circumstances, which may impact the number of carbon reductions issued in a project timeframe. RIL is currently implemented in the commercial production reserves, however it its effectiveness to reduce carbon from entering the atmosphere under the Climate Convention in Malaysia is unclear. Representing extremes along a range of anthropogenic disturbance through RIL activities, data from RIL activities was collected in a lower montaine forest harvested once, and a lowland forest, harvested multiple times. Both areas were tested against the carbon baseline, to represent conventional harvest practices in Sabah. The estimates were comparable to literature values, with RIL activities found to reduce carbon from entering the atmosphere. The variability in the accumulation of carbon stocks of aboveground alive tree biomass was identified as an important consideration in the trends observed. The condition of the forest at the time of harvest, i.e., primary or severely degraded logged-over forest, was found to impact carbon stocks immediately after harvest and the rate of carbon accumulation over time. The variability of the result supports the concept of conservativeness, as advocated for project-based activities, under the Climate Convention. As a signatory Party, Malaysia is developing the necessary institutional infrastructure to facilitate project-based activities under the Climate Convention. Investigating RIL as a nationally appropriate mitigation action is undertaken, where distinctions are made between its integration at the national level, and its implementation at the sub-national level. Drawing on experiences from Sabah, implementing RIL as a project-based activity under the Climate Convention is broadly applicable to all States in Malaysia, whereby monitoring, reporting and verification at the sub-national level may be implemented through the existing domestic forest certification standard in Malaysia. At the current price of carbon over a 35-year harvest cycle, RIL is estimated to be approximately at the break-even price for its implementation in Sabah. Relative to the cost of restoring severely degraded forests harvested through conventional practices in Sabah, implementing RIL is financially viable. The knowledge gained by investigating RIL as a sub-national approach may be useful to assist Malaysia to meet their intended national emission reduction targets under the Climate Convention. This thesis aims to improve our knowledge of the application of RIL in logged-over forest of Sabah, and its applicability as a project-based activity under the Climate Convention in Malaysia. Several research questions were raised, to contextualise the modalities of RIL in Sabah and the institutional framework in Malaysia, relative to the architecture of the Climate Convention. It highlights the need for a systematic approach to gather observations on forest carbon dynamics and their integration into larger carbon accounting frameworks, to improve our understanding of the potential of RIL to contribute to reduce carbon emissions into the atmosphere from the forest sector.
7

Community-based sustainable forest managment: A case study of Rutland Township, Ohio

Hoffman, Deborah L. 26 April 2006 (has links)
No description available.
8

Stand dynamics of mixed-Nothofagus forest

Hurst, Jennifer Megan January 2014 (has links)
Sustainable management of mixed-species forests for timber is underpinned by research on forest stand dynamics and quantification of tree recruitment, growth and mortality rates. Different performance among species across light gradients theoretically prevents more shade-tolerant species from excluding shade-intolerant species, driving succession and allowing species coexistence. This research investigates stand dynamics and performance trade-offs for co-occurring tree species: Nothofagus fusca (red beech) and Nothofagus menziesii (silver beech), which together dominate extensive areas of New Zealand’s indigenous forest. Using permanent plot data, measurements of permanently tagged individuals are used to quantify recruitment, growth and mortality rates for each species, across size classes and life-history stages (i.e. seedlings, trees). First, seedling growth and mortality is examined in relation to microhabitats (e.g., light, substrate type) and contrasted with patterns of seedling abundance. Second, spatially explicit permanent plot data are used to examine tree growth in relation to competition, local disturbance and tree size over a 23-year period. Third, the influence of competition and disturbance on tree mortality and spatial patterns of tree mortality are examined. Fourth, a simulation model for tree population dynamics is parameterised for mixed-Nothofagus forest and used to evaluate long term consequences of disturbances (e.g. alternate harvesting regimes) on structure and composition. Small-scale disturbance favoured each species at different life stages and for different measures of performance (i.e. recruitment, growth or mortality). N. fusca seedlings and trees grew fast in high light microhabitats, such as those created by small-scale disturbances, but adult N. fusca mortality was elevated near sites of recent disturbance. By contrast, N. menziesii trees grew faster near sites of recent disturbance, which may help this species persist. Consequently, simulation results showed that small-scale disturbance frequency was a major determinant of forest composition and structure, determining whether N. fusca or N. menziesii is dominant. The simulation model could be developed further and used to inform the sustainable management of mixed-Nothofagus forests.
9

An investigation into sustainable forest policies and practices in Syria

Al Berni, Rim Rateb January 2010 (has links)
Appreciation of how forest land can be managed in a sustainable way in arid and semi-arid zones (ASAZs) of centralized countries is limited. Accordingly, this thesis seeks to analyse the role of government and communities, including women, in the formulation and implementation of sustainable forest management (SFM) policy and practices in the semi-arid environment of Syria where such land is limited in extent (e.g. 3% forest and 57% rangeland) and yet where its high biodiversity value is of international significance. The thesis employs a variety of methods: a case study approach (Syria); a questionnaire (i.e. 142 respondents); face-to-face interviews (i.e. 26 interviewees); participant observation and secondary data. The SFM model was used to organise and analyse the influences of environmental, economic, social, cultural and political issues on the state of forest land in Syria. Three contrasting forest areas were selected for detailed analysis at local level: Al Foronloq had the Arab Institute of Forestry close by and the area had a high biodiversity value for landscape; Abo Kbeis contained key genetic resources and a number of women there had been trained in forest management and Abd Aziz Mountain was characterised by rangeland with traditional grazing plus a very arid environment. The main results obtained from census data confirmed that Syrian forest lands have diminished considerably since 1900 with regard to their geographical extent due to agricultural development, expansion of rural-urban settlements as well as of agricultural land onto Syrian forest land. On a more general level, the political issues in Syria (i.e. centralization and independency of the country) demand development of the internal resources of the country, such as agricultural production, in order to cover the needs of human maintenance. Scrutinising forest documentation and using results of face-to-face interviews, it was found that there were considerable changes in forest policies in terms of forest protection and plantation. In addition, there was a recent indication of adopting SFM principles in the case study area, largely as a result of action by agencies external to Syria at the national level, and the new role of NGOs in forest management at the local level. The increasing level of awareness of environmental problems; the capacity of institutions; community participation in natural resources management and achieving international agreements were also found to be paramount in any contracts between the Syrian government and other organisations. This thesis, at the local level, showed that respondents in the mountains (in the Abd Aziz Mountain (AAM) study area) seemed to be older, poorer, mostly with non-educated background, with more than three children, than in the Al Foronloq (AF) and Abo Kbeis (AK) study areas. Respondent groups in AAM were found to be more dependent upon forest resources than respondents in AF and AK; and they occupied land illegally because of their mission to develop agricultural activities, including grazing. The study confirmed that educated households in AF and AK use forest resources more than non-educated households. Conversely, non-educated households in AAM suffer from gaining a local income which may in turn affect their attitudes and behaviours in using forest resources; and as consequence, householders suffering from financial problems may be less aware of the importance of forest protection and try to solve their individual needs by increasing the pressures on the forest resources. The major constraints affecting the formulation and implementation of SFM policy are insufficient financial resources, inadequate management from national to regional and local levels; the limitations are also related to local communities’ attitudes and ignorance of the role of women in forest management. This thesis found that the contribution of women in the labour force at the local level was high in Lattakia (Al Foronloq study area) compared with other study areas (e.g. 32.9% in Lattakia against 13.4% in Hamah and 18.8% in Alhasake) (UNDP: Syrian Human development, 2005); although, there was a significant relationship between income level, family size and women’s contribution in forest management at the local level and no significant relationship with the educational level. On a more specific level, the role of religious faith in AK affects the contribution of women in the society and the workplace generally and in forest management in particular. Finally, the application of the SFM model in this study provided a flexible approach for analysis of complicated interactions between the government and communities. It also provided a comprehensive framework for different types of analytical purposes. Each of the three main components (issues, state and political decisionmakers) was divided into several sub-components which facilitate the explanation and identification of the complexities affecting the formulation of SFM policy and the implementation of such policy. It helped to provide a set of policy recommendations which may help to increase future community participation in forest management and reduce the influences of community pressures on forest resources in Syria.
10

Dynamics of Forest Cover Extent, Forest Fragmentation and Their Drivers in the Lake Victoria Crescent, Uganda From 1989 to 2009

Waiswa, Daniel 29 April 2011 (has links)
Despite the important values forests play in the tropics, sustainable forest management still remains a challenge as manifested through continued forest loss. The objective of this study was to provide information on the dynamics of forest cover and their drivers vital for enhancing sustainable forest management in the Lake Victoria crescent, Uganda. Several methodologies including remote sensing and Geographic Information Systems techniques, analysis of landscape patterns and various social science techniques were integrated in working towards the stated goal. Results showed that the Lake Victoria crescent, Uganda covering an area of about 1,509,228 ha, experienced a decline in forest cover from 9.0% in 1989 to 4.4% in 2009. This was in comparison with non-forest cover which increased from 58.7% in 1989 to 63.5% in 2009 while open water coverage generally remained unchanged averaging 32.3% from 1989 to 2009. Mean annual deforestation rate from 1989 to 2009 decreased with a weighted mean rate of 2.56%. Both deforestation and afforestation declined between 1989 and 2009 although deforestation still exceeded afforestation. In addition to deforestation, the Lake Victoria crescent also experienced forest fragmentation from 1989 to 2009. Forests greater than 100 ha in size were the most vulnerable to forest fragmentation yet they still constituted a big proportion of forest cover in 2009. Deforestation was a consequence of proximate causes which were triggered by a number of underlying drivers acting singly or in combination, with underlying drivers being more influential. In a bid to promote sustainable forest management, there is a need to continue with efforts to curb deforestation and forest fragmentation, especially amongst forests greater than 100 ha. This could be achieved through empowerment of local communities to take a core role in sustainable management of forest resources. / Ph. D.

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