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This study is to assess natural resource management practices in Xilingol Biosphere Reserve (XBR) located in northern China in their institutional contexts. Institutions including legislation, regulations and administrative structures, responsibilities associated with land and resource rights, decision making powers and processes, and community participation, and the interactions between these institutions have exerted great impacts on how natural resources are used and managed in XBR. Local people have experienced great socioeconomic losses accompanied with the establishment of XBR. However, they have not been provided with adequate compensation for their lost benefits. This gave rise to the conflict between local people and XBR. The findings indicate that partnerships prove to be an inevitable trend for improving the reserve management and facilitating the resolution of a series of issues facing XBR.

This study is to assess natural resource management practices in Xilingol Biosphere Reserve (XBR) located in northern China in their institutional contexts. Institutions including legislation, regulations and administrative structures, responsibilities associated with land and resource rights, decision making powers and processes, and community participation, and the interactions between these institutions have exerted great impacts on how natural resources are used and managed in XBR. Local people have experienced great socioeconomic losses accompanied with the establishment of XBR. However, they have not been provided with adequate compensation for their lost benefits. This gave rise to the conflict between local people and XBR. The findings indicate that partnerships prove to be an inevitable trend for improving the reserve management and facilitating the resolution of a series of issues facing XBR.

No description available.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. 24 March in Johannesburg, South Africa, 2014. / The Biosphere Reserve (BR) model of UNESCO’s Man and the Biosphere Programme (MAB) reflects a shift towards more socially accountable conservation, setting a basis for improving the relationships between people and their environment. The BR approach of dual ‘conservation’ and ‘sustainable development’ objectives is a long-term perspective that increases people’s ability to sustainably manage environmental resources into the future. By 2013 the MAB Programme had resulted in 621 sites designated globally since first inception in 1976, with 11 of these new listings since 2012. Yet regardless of this global spatial expansion, there are few examples of BRs successfully conforming to the MAB’s full criteria, as the reality of aligning conservation and development goals in this model has typically favoured one over the other, with examples of development objectives fuelling broad-scale landscape transformation and conservation objectives that have ignored socio-economic opportunities. However there are a number of case studies presented herein that have shown considerable success, and this thesis suggests that the potential opportunities inherent in the model may outweigh implementation challenges. This thesis critically reviews the history and evolution of the Programme internationally, and makes recommendations for the future of the MAB Programme. In the South African context, the BR model has been applied to a regional conservation landscape in the north-eastern part of the country. The Kruger to Canyons Biosphere Reserve (K2C) is a long-established land-use mosaic of socio-economic juxtapositions, where nationally important economic sectors and world-renowned protected areas (e.g. the Kruger National Park) neighbour extensive, mostly rural, human populations engaged in informal livelihood practices. These vast settlement expanses are artefacts of the former political system in South Africa, and have been prioritised by the South African National Government for urgent socio-economic upliftment. Given that understanding the underlying land-use mosaic is essential for successful implementation of the BR model in any landscape, this thesis assessed land-cover change across the BR (1993 – 2006 – 2012), through the creation of land-cover classification maps, analysing spatial changes in cover relative to the MAB theoretical aspirations. It focuses on three consolidated land-cover cover classes: Intact Vegetation, Impacted Vegetation and Settlement, that present a graduated scale of land-use intensities across the BR, acting as surrogates for the ‘environmental’ and ‘human utilisation’ aspects of the BR approach. Results indicate that the spatial distribution of land-cover change in K2C bears little regard for the theoretical BR zonation and the relative limitations on ‘use’ that typifies successful BR implementation. The spatial expansion of Settlement cover replaced adjacent Impacted Vegetation, which in turn encroached in original areas of Intact Vegetation cover, increasingly fragmenting Intact Vegetation across K2C. The expansion of Impacted Vegetation has resulted in the spatial consolidation of communal use areas, which has likely serious implications for the long-term sustainability of current harvesting levels. Anecdotal field observations have indicated community responses to these concerns with the formal fencing of rangelands to secure ownership and control access. Losses of Intact vegetation translate spatially into an area >400km2, with observed land-cover changes occurring beyond the transition zone, encroaching into the (fully-protected) core and (partially–protected) buffer zones. The increased rate of landscape change in the recent observation period (2.3%1993-2006 versus 5.7%2006-2012) poses challenges for landscape management, with future predictions of escalating transformation likely to undermine BR sustainability, as well as options for a regionally connected protected area network. Historical landscape trends predict a further 5.1% loss of intact vegetation in the next 6 years (2012 – 2018), yet this may over-estimate the potential for transformation in this landscape. However the possibility of a similar loss over a longer temporal period, i.e. 12 years, is not improbable, with the unprotected matrix landscape of the transition zone having experienced comparable losses since 1993, i.e. 4.17%. K2C has had substantial success with pilot socio-economic projects, and has received formal international recognition for the stakeholder engagement / alignment occurring in the subregion as a result of the BR’s listing here. Given these successes, and the considerable investment in its establishment, it is likely that the BR model here will endure. The results of this thesis contribute to improving implementation success long-term, informing policy and management priorities across the BR. These include contributions to i) a marketing approach for the BR, specifically the importance of a K2C ‘brand’ for enhancing co-operation and strengthening the BR’s regional identity, as well as ii) providing support for land-use planning and decisions related to land-use practices and BR sustainability.

L’ozone (O3) est un gaz reconnu comme un des polluants atmosphériques majeurs du XXIème siècle, de par ses propriétés très oxydantes. Dans les plus basses couches de notre atmosphère, ce polluant secondaire est produit par des réactions photochimiques impliquant des précurseurs émis par les activités humaines et la végétation. De nombreuses études expérimentales ont révélées le caractère phytotoxique de l’O3, qui dégrade sévèrement la photosynthèse, réduit le rendement des récoltes et inhibe la croissance des arbres. Afin de quantifier les effets de l’O3 sur les écosystèmes à l’échelle globale, des modèles numériques ont été développés. Dans cette thèse, nous avons principalement développé un nouveau modèle d’impact basé sur le concept dose/réponse au sein du modèle global de végétation ORCHIDEE. L’approche semi-mécaniste utilisée vise à représenter de manière simplifiée les effets du stress oxydatif causés par l’O3 sur la photosynthèse. L’étalonnage des paramètres a été réalisé en utilisant des données physiologiques issues majoritairement d’expériences de fumigation à l’air libre et en chambres à ciel ouvert menées pendant la saison de croissance de plusieurs espèces végétales. Cette étape de calibration a permis de déterminer les paramètres spécifiques à plusieurs types fonctionnels de plantes. La sensibilité du modèle à l’O3 et à son interaction avec le CO2 et le stress hydrique a ensuite été testée. A l’échelle locale, notre modèle d’impact reproduit fidèlement l’allure de la réponse de la photosynthèse observée in situ à l’échelle saisonnière, et l’élévation du CO2 compense partiellement l’impact de l’O3. En outre, le couplage entre la photosynthèse et la conductance stomatique dans ORCHIDEE permet de simuler la limitation des effets de l’O3 par les flux entrants. La fermeture stomatique réduit également la transpiration, ce qui augmente l’humidité du sol et préserve ainsi la végétation d’un stress hydrique accentué. Cependant, les effets observés sur la respiration autotrophe ne sont pas représentés et l’impact sur la surface foliaire est sous-estimé. Afin d’évaluer la performance du modèle, nous avons comparé l’impact simulé sur la productivité nette (NPP) annuelle avec l’effet estimé par les relations empiriques linéaires standards, recommandées par l’UNECE pour évaluer les risques phytotoxiques chez plusieurs types d’écosystèmes. En outre, à l’échelle globale, nous obtenons des résultats similaires aux estimations réalisées avec un autre modèle de végétation munie d’une paramétrisation d’impact différente. Enfin, nous estimons que les concentrations actuelles causent localement une chute de productivité nette totale annuelle allant jusqu’à 11.7% en moyenne dans le nord-est des Etats-Unis, et réduirait le contenu en carbone du sol de 10.9% dans cette région et de 42.5% en Indonésie si la pollution actuelle perdure pendant 50 ans. Ce travail indique que l’impact de l’O3 sur la végétation est non-négligeable dans le modèle ORCHIDEE, et doit être pris en compte dans les études globales du bilan de carbone terrestre. / Ozone (O3) is a gas recognized as a major atmospheric pollutant of the 21st century, due to its strong oxidant properties. As a secondary pollutant, O3 is produced by photochemical reactions between both anthropogenic and biogenic precursors. Numerous experimental studies have highlighted the phytotoxic effects of O3, which severely impairs photosynthesis, reduces crop yields and forest growth. Numerical models are used in order to quantify the impact of O3 at global scale. In this thesis, the major work was to develop a new parameterization based on the dose/response concept and to integrate it in the global vegetation model ORCHIDEE. We used a semi-mechanist approach to represent the effects of oxidative stress induced by O3 on photosynthesis. Parameters were obtained by comparing modelled and observed physiological variables related to free-air and open-top chamber fumigation experiments, carried out during the growing period for different plant species corresponding to several plant functional types in the model. Sensitivity tests were conducted to evaluate the influence of O3 and its interactive effects with CO2 and water-stress on the ecophysiological processes in ORCHIDEE. We reproduced the curvilinear response observed on photosynthesis at the leaf level during a growing season, and the elevation of CO2 concentration partially mitigates the O3 effect. The induced simulated stomatal closure slows down the impact on photosynthesis coupled to conductance by reducing the entering O3 fluxes. It also decreases transpiration and increases soil water content, which protects vegetation from higher water-stress. However, observed changes in autotrophic respiration are not simulated and the impact on foliar surface is underestimated. In order to evaluate the performance of our model, we compared the simulated impact on annual net primary productivity (NPP) with the empirical linear dose/response relationships recommended by UNECE to assess the risk for different types of ecosystems. Moreover, at global scale, we found results similar to those from another land surface model using a different impact relationship. Finally, we estimated that current O3 concentrations cause locally a decrease in total annual net productivity up to 11.7% on average in the north-west of USA, and could decrease the soil carbon content by 10.9% in this region and by 42.5% in Indonesia, if current O3 pollution remains the same for 50 years. This work confirms that impact of O3 on vegetation is non-negligible in the model ORCHIDEE, and must be considered in global carbon budget modelling.