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Evaluation of the impact of climate and human induced changes on the Nigerian forest using remote sensingIke, Felix January 2015 (has links)
The majority of the impact of climate and human induced changes on forest are related to climate variability and deforestation. Similarly, changes in forest phenology due to climate variability and deforestation has been recognized as being among the most important early indicators of the impact of environmental change on forest ecosystem functioning. Comprehensive data on baseline forest cover changes including deforestation is required to provide background information needed for governments to make decision on Reducing Emissions from Deforestation and Forest Degradation (REED). Despite the fact that Nigeria ranks among the countries with highest deforestation rates based on Food and Agricultural Organization estimates, only a few studies have aimed at mapping forest cover changes at country scales. However, recent attempts to map baseline forest cover and deforestation in Nigeria has been based on global scale remote sensing techniques which do not confirm with ground based observations at country level. The aim of this study is two-fold: firstly, baseline forest cover was estimated using an ‘adaptive’ remote sensing model that classified forest cover with high accuracies at country level for the savanna and rainforest zones. The first part of this study also compared the potentials of different MODIS data in detecting forest cover changes at regional (cluster level) scale. The second part of this study explores the trends and response of forest phenology to rainfall across four forest clusters from 2002 to 2012 using vegetation index data from the MODIS and rainfall data obtained from the TRMM.
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Tree cover in the early Holocene in temperate Europe and implications for the practice of re-wilding in nature conservationBaker, Ambroise G. January 2014 (has links)
This thesis addresses the methodological challenges of determining the variability of large herbivore populations through time and their impact on European vegetation. Large herbivores are at the heart of conservation policy. However, opinions widely diverge on whether we should aim for fewer herbivores and managed populations or, on the contrary as advocated by the rewilding movement, more herbivores and self-regulating populations acting as ecosystem engineers. This controversy has roots in a debate regarding the nature of ecosystems before the prevalence of human activities. Baseline ecosystems are either described as continuous forest cover with passive large herbivores, or, in contrast, as mosaics with patchy forest cover driven <i>inter alia</i> by bison, aurochs and horses, now rare or extinct in Europe. The main obstacle in moving this debate forward is a poor understanding of large-herbivore densities in the past. I analysed modern pollen and spore assemblages from known environmental settings to improve palaeoecological interpretation of fossil assemblages dating from the pre-human (baseline) period. The sites investigated are the rewilded grasslands of the Oostvaardersplassen (The Netherlands), the mosaic habitats of The New Forest (UK) and the old-growth closedcanopy forest of Białowieża (Poland). I demonstrate that the common practice of interpreting pollen percentages fails to estimate past forest cover in situations with natural grazing. As an explanation, I suggest that pollen productivity fluctuates with biotic factors such as herbivory and canopy shading. As a result, new insights into the baseline debate require additional lines of evidence. In this thesis, I develop an existing methodology to reconstruct past herbivore presence using fossil dung fungal spores. I synthesise current knowledge of this method with an emphasis on spore identification and, finally, I demonstrate that dung fungal spore abundance in lake sediments can be translated into large herbivore numbers. The evidence presented in this thesis contributes to the debate on re-wilding and addresses a fundamental challenge of nature conservation in the human-dominated landscapes of Europe.
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Assessment habitat outcomes of floodplain forest restoration : case study at the Ouse Valley ParkPerez Linde, Natalia January 2016 (has links)
The research project for this PhD set out to provide a best practice example of bringing together industry (Hanson Heidelberg Cement Group), a charitable body (The Parks Trust), non-departmental public body (Environment Agency) and academia (Cranfield University). The Parks Trust (landowner) and Hanson (quarry operator) worked together with the vision of creating a new floodplain forest landscape along a 1 km reach of the River Great Ouse following extraction of gravels from the site. It was the first project of its kind in the United Kingdom where planning permission was obtained specifically for the creation of a floodplain forest habitats post quarrying. The aim of the PhD research was to determine appropriate ecological approaches to apply to the assessment and future monitoring of habitat outcomes of a floodplain forest restoration project at a mineral extraction site. A central element of the research was the design of a scientifically justified monitoring programme, with key variables determined being: soil characteristics, water quality, vegetation development, site topography and water table level data. An Adaptive Monitoring Framework (AMF) was chosen to set the proposed monitoring within which was complemented with the hypothesis - The ratio of wet/dry vegetation within the floodplain forest is determined by the site topography and water table level. The hypothesis was tested by analysis of the key variables through fieldwork and existing data sources supplemented with a study of the water table level interaction with two typical floodplain forest tree species (Salix viminalis and Populus trichocarpa x deltoides) in a glasshouse experiment. Findings from the field and experimental research were then used within a spatially based landscape ecology scenario approach to identify the most suitable areas of the study site for specific species planting according to soil-water levels and topography in the floodplain forest. Outputs of this research enhance understanding of the key aspects to consider when assessing floodplain forest re-creation/restoration and enable guidelines and recommendations to be developed for land managers based on a long-term and an adaptive ecological monitoring approach. These management guidelines and recommendations based on a systematic scientific approach applied within the research should be appropriate to other similar restoration projects. The research provides the background evidence on what should be measured to determine the environmental changes of the floodplain forest habitat restoration as it develops towards restoration success.
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Modelling adaptation strategies for Swedish forestry under climate and global changeBlanco González, Víctor January 2017 (has links)
Adaptation is necessary to cope with, or take advantage of, the effects of climate change on socio-ecological systems. This is especially important in the forestry sector, which is sensitive to the ecological and economic impacts of climate change, and where the adaptive decisions of owners play out over long periods of time. These decisions are subject to experienced and expected impacts, and depend upon the temporal interactions of a range of individual and institutional actors. Knowledge of, and responses to, climate change are therefore very important if forestry is to cope with, or take advantage of, the effects of climate change over longer timescales. It is important to understand the role of human behaviour and decision-making processes in the study of complex socio-ecological systems and modelling is a method that can support experiments to advance this understanding. This study is based on the development of CRAFTY-Sweden; an agent-based model that allows the exploration of Swedish land-use dynamics and adaptation to climate change through scenario analysis. In CRAFTY-Sweden, forest and farmland owners make land use and management decisions according to their objectives, management preferences and capabilities. As a result of their management and location characteristics they are able to provide ecosystem services. To explore future change, quantitative scenarios were used that considered both socio-economic development pathways and climatic change. Simulations were run under the different scenarios for the period 2010-2100, for the whole of Sweden. Furthermore, because institutions (i.e. organisations) also influence socio-ecological systems through their actions and interactions between them and with land owners and the environment, a conceptual model of institutional actions applied to socio-ecological systems was developed. The application of this conceptual model was explored through a model of institutions that can act, interact and adapt to environmental change in attempting to affect ecosystem service provision within a simple forestry governance system. I found that forestry in the future will likely be unable to meet societal demands for forest services solely on the basis of autonomous adaptation. A northward expansion of agriculture and especially of forestry proved positive for both sectors to adapt to changing conditions, under several scenarios, given the substantial land availability and the improved environmental conditions for plant growth. Legacy effects of past land-use change can have a great impact on future land-use change and adaptation processes, especially in forestry. Also, greater competition for land may lead to shorter forest rotation times. Socio-economic change and land owner behavioural differences may have a larger impact on owner competitiveness, land-use change and ecosystem service provision than climate-driven changes in land productivity. Different owner objectives and behaviour resulted in different levels of ecosystem service provision. Also, particular forest types were differently suitable for adaptation depending on the sets of objectives under which they were managed. Owners implementing particular management strategies can be differently competitive under different future scenarios, and the suitability of such strategies for adaptation is not a static, inherent characteristic of a system. Instead, it evolves in response to changing contexts that include both the external global change drivers and the internal dynamics of agent interactions. Additionally, institutional conceptual models as presented here can support better understanding of the key institutional decision-making dynamics and their consequences, endogenously, flexibly across different socio-ecological systems. Finally, study limitations, future research and the policy relevance of findings are discussed.
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Enhancing productivity and estimation of carbon in CDM forestry projects : a Malawi case studyMakungwa, Stephy David January 2016 (has links)
This thesis offers a method that informs on the most appropriate sites for successful tree establishment and provides protection to the planted trees in CDM forestry projects. It also offers a method that can accurately and precisely estimate woody biomass in CDM forestry projects established on an agricultural landscape. The thesis has established a set of evaluation criteria that are defined and generally agreed upon by a panel of local forestry experts in Malawi. These criteria express the degree of appropriateness of particular locations to support successful tree establishment and growth, and protect the planted trees from deforestation and forest degradation. They also influence farmers’ decision-making to allocate land for either tree planting or other competing land use options, e.g. crop cultivation. The thesis uses these evaluation criteria to functionally identify priority sites on the landscape of Central Malawi for the establishment of CDM forestry projects. The priority sites are identified using trade-off analysis tools of the GIS-based MCA protocols. Besides site identification, the thesis has established a magnitude of discrepancy that can result from the use of imported allometric models in estimating woody biomass in CDM forestry projects. Imported allometric models consistently under-estimate the woody biomass of the growing trees in the study area with a mean prediction error of as high as 50%. Local allometric models are therefore developed and they are found to be both accurate and precise in estimating woody biomass. These results imply that identification of priority sites, and accurate and precise estimation of woody biomass in CDM forestry project activities are likely and can be attained. In turn, successful establishment of CDM project activities lead to enhanced productivity that will attract expanded investments in CDM forestry projects. The thesis uses Malawi as a case study. The findings of this thesis can be scaled out to other countries whose socio-ecological characteristics are similar to Malawi. These are mostly tropical countries of the Sub-Saharan Africa. In so doing, the thesis contributes to improving productivity and estimation of carbon in CDM forestry project.
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Land use, food production, and the future of tropical forest species in GhanaPhalan, Benjamin Timothy January 2010 (has links)
Agriculture is arguably the greatest threat to tropical forest species. Conservation scientists disagree over the relative importance of two opposing strategies for minimising this threat: enhancing on-farm biodiversity, through wildlife-friendly farming practices, or sparing land for nature by using high-yielding farming methods on the smallest possible area to reduce the need to convert natural habitats. Previous theoretical work shows that understanding the relationship between population density and yield for individual species is crucial for determining whether one of these strategies, or a mixed strategy, will maximise their populations for a given food production target. In this thesis, I aim to identify what land-use strategy will permit increases in food production with least impact on species in the forest zone of Ghana. Farm-fallow mosaic landscapes with shifting cultivation and native canopy trees produced only around 15% as much food energy per hectare as the highest-yielding oil palm plantations. In farm mosaics where perennial tree crops dominate, food production and profits were higher, but did not reach those of oil palm plantations. I surveyed birds and trees in forest, farm mosaic, and oil palm plantation, and combined these data with information on yields to assess the likely consequences of plausible future scenarios of land-use change. My results provide evidence of a strong trade-off between wildlife value and agricultural yield. Species richness was high in low-yielding farming systems, but there was considerable turnover between these systems and forests, with widespread generalists replacing narrowly endemic forest-dependent species. Species most dependent on forest as a natural habitat, those with smaller global ranges and those of conservation concern showed least tolerance of habitat modification. For virtually all species, including even widespread generalists, future land-use strategies based on land sparing are likely to support higher populations of most species and minimise their risk of extinction compared to land-use strategies based on wildlife-friendly farming. If food production is to increase in line with Ghana‘s population growth, a combination of efforts to improve forest protection and to increase yields on current farmed land is likely to achieve this at least cost to forest species. Efforts to better protect forests, which require further restrictions on human use, might be most effective if they can be closely linked to support for farmers to improve their yields. In the long term however, this strategy will only delay and not avert biodiversity loss, unless global society can limit its consumption.
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La protection juridique intégrée des forêts en Côte d'Ivoire / The legal protection integrated by forests into Ivory CoastDoua, Marcel 22 January 2015 (has links)
La forêt ivoirienne connait une dégradation très avancée. Pour la préserver, la Côte d’Ivoire a élaboré la loi n° 65-425 du 20 Décembre 1965 portant code forestier et ses textes d’application. Mais ce premier instrument juridique de protection n’a pas eu l’efficacité escomptée. En effet, de portée sectorielle, la loi forestière ne peut régir tout le domaine forestier. D’autres légalisations sectorielles telles la loi de 1965 sur la chasse, le code de l’eau, la loi de 1998 sur le droit foncier rural devront intervenir pour combler le déficit législatif du code forestier. Il en résulte une législation relative à la forêt et ses ressources non coordonnée et non intégrée dont les conséquences sont les risques évidents de chevauchements de compétence, sources de conflits et de blocage et les doubles emplois. Pour assurer un cadre juridique idoine à la protection de la forêt ivoirienne, cette intégration juridique doit pouvoir prendre en compte toutes les dimensions sociopolitiques et conomiques des forêts, assurer la participation de tous les acteurs, permettre l’intégration du contenu des textes et requérir unecoopération des structures de gestion / The Ivorian forest is facing advanced degradation. To preserve it, Côte d’Ivoire has drafted Law No. 65 - 425 dated 20 december 1965 on the Forest Code and its implementing regulations. But first legal instrument of protection was not as effective as expected. Indeed, sectoral scope , forest law can govern the entire forest area. Other sectoral legalization as the 1965 Law on hunting, the Water Code, the 1998 Law on rural land law will step in to fill the legislative gap in the forestry code. The result is a law on the forest and its uncoordinated and non-integrated resources, the consequences are obvious risks of overlapping jurisdiction, sources of conflict and blocking and duplication. To ensure appropriate legal framework for the protection of the Ivorian forest, this legal integration must take into account all socio-political and economic dimensions of forests, ensuring the participation of all stakeholders, allow the integration of text content and require a cooperation of management structures
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Du rendement soutenu à l'aménagement forestier durable : Quelle gouvernance pour le Québec ? / From Sustained Yield to Sustainable Forest Management : What Form of Governance for Quebec ?Gassama, Ibrahima 16 September 2016 (has links)
Cette thèse est une exploration pour rendre opérationnel le concept d'aménagement forestier durable, en dépassant les perspectives proposées par le rendement soutenu. Dans ce cadre, la démarche n'est pas de calculer l'évolution de la production des volumes de bois pour en garantir un flux constant, mais bien la définition, par la diversité des acteurs, de la cohérence dans le développement d'une diversité d'activités forestières. Cette démarche nécessite non seulement un éclairage associé à la connaissance experte, mais aussi à la connaissance provenant des acteurs des activités forestières et des acteurs de la gouvernance pour comprendre les effets de tels développements sur le territoire. La réalité, sur le terrain montre que la préoccupation des acteurs du milieu forestier va au-delà de la préservation des volumes de bois.Ainsi, la durabilité forestière englobe d’autres valeurs et usages non ligneuses et non monétaires. Une évaluation de ces autres valeurs ne saurait se faire sans la création d’une démarche participative dont la finalité est de construire les préférences par les acteurs eux-mêmes. Ainsi, l’aménagement forestier durable devient un problème de choix social afin d’identifier les formes d’aménagement acceptables par les acteurs du territoire. Cette recherche s’attèlera à ressortir ces préférences sociétales sur le territoire pilote du Saguenay-Lac-Saint-Jean par une démarche délibérative et des outils multimédias de la médiation des connaissances. / This thesis is an exploration to operationalize the concept of Sustainable Forest Management, overcoming the prospects offered by the concept of Sustained Yield. In this context, the approach is not to calculate the evolution of production volumes of wood to ensure a constant flow, but to define by the diversity of stakeholders, the consistency in the development of multiple forest activities. This approach requires an associated lighting expert knowledge but also knowledge from actors in forestry and governance stakeholders to understand the effects of such developments in the area. The reality on the ground shows that the concern of forest stakeholders goes beyond the preservation of wood volumes.Thus, forest sustainability encompasses other non-timber and non-monetary values and uses. An evaluation of these other values cannot be achieved without the creation of a participatory process whose aim is to build preferences by the actors themselves. Thus, Sustainable Forest Management becomes a social choice problem to identify acceptable forms of development by local actors. This research will strive to highlight the societal preferences on the pilot territory of Saguenay-Lac-Saint-Jean by a deliberative approach and multimedia tools of mediation of knowledge.
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L'évaluation des performances des universités au regard du développement durable : une perspective internationale / Assessing university performances toward sustainable development : an international perspectiveBouckaert, Mathias 09 November 2016 (has links)
Dans le cadre de la transition des sociétés vers le développement durable, le rôle des universités est de plus en plus mis en évidence. A cet égard, l’évaluation, en tant qu’outil d’accompagnement des organisations pour l’amélioration de leurs performances, peut s’avérer d’une aide précieuse.Le potentiel d’application de l’évaluation reste toutefois limité. L’université et la durabilité apparaissent comme des objets normatifs dont la définition du contenu est source de nombreuses oppositions. En outre, leur réalité est évolutive et sujette à d’importants degrés d’incertitude et de complexité paradoxale.Le présent travail vise à déterminer les conditions à travers lesquelles l’évaluation peut apporter un avantage, sinon constituer un frein, à l’amélioration des performances des universités en matière de durabilité. Il se présente en deux grandes parties.La première porte sur la construction théorique de la norme d’évaluation des « performances durables de l’université». Elle repose sur l’examen approfondi des spécificités de l’université et de la durabilité ainsi que sur une analyse empirique de plusieurs cas pratiques relevés à l’international.La deuxième partie confronte et consolide les enseignements de la première en se concentrant sur le développement d’une méthodologie opérationnelle d’évaluation. Pour ce faire, un processus participatif multi-parties prenantes a été mis en œuvre et a conduit à la construction d'un dispositif multidimensionnel regroupant plus de 50 indicateurs. Cet outil se veut être une contribution à l’édification de systèmes d’évaluation mis à disposition des acteurs académiques pour l’identification de pistes d’amélioration de leurs performances au regard du développement durable. / In the context of the transition of societies towards sustainable development, the role of universities is increasingly highlighted. In this respect, assessment, as a support tool for organizations whishing to improve their performance, can be of great assistance. Opportunities for the application of assessment remains however limited. The university and sustainability are normative objects and their definition is subject to considerable opposition. In addition, their reality is progressive and characterized by high levels of uncertainty and paradoxical complexity.This work aims to determine the conditions under which assessment practices can support, or otherwise hinder, the performances of universities toward sustainability. It comes in two parts.The first part focuses on the theoretical construction of an evaluation norm for the "sustainable performances of universities". It is based on a comprehensive review of the specific features of the university and sustainability, as well as on an analysis of several best practices identified internationally. The second part compares and strengthens those findings by focussing on the design of an operational assessment methodology. This research was conducted through a multi- stakeholder participatory process that led to the building of a multidimensional framework comprising more than 50 indicators. This tool aims to be a contribution to the development of assessment methods for academic actors willing to identify ways of improving their performances with respect to sustainability.
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Akustische Abschirmwirkung von WäldernBarth, Manuela, Ziemann, Astrid, Bernhofer, Christian 28 April 2015 (has links)
Der Bericht beschreibt, wie die akustische Abschirmwirkung von Wäldern mit Hilfe eines akustisch-meteorologischen Modells ermittelt werden kann.
Aus den Berechnungen werden meteorologische Zusatzdämpfungen für die Vegetationsarten Wiese, Nadelwald und Laubwald abgeleitet.
Insbesondere im schalltechnisch kritischen Nachtzeitraum ist Nadelwald in einem lockeren Bestand für Schallschutzmaßnahmen am besten geeignet. Durch Schallschutzmaßnahmen in Form von Waldflächen kann eine deutliche Verbesserung des Schallschutzes in der Nähe von Straßen und Schienen erreicht werden. Die Veröffentlichung dient der Unterstützung von Planungsempfehlungen für einen verbesserten Schallschutz und wendet sich insbesondere an Immissionsschutz- und Forstbehörden.
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