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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.
281

Participatory mapping of ecosystem service values in the Kristianstads Vattenrike Biosphere Reserve

Schwarze, Marleen January 2024 (has links)
UNESCO Biosphere Reserves are examples of multifunctional landscapes recognized as sources of ecosystem services and laboratories for sustainable development. Participatory mapping of ecosystem services reveals where residents value ecosystem services in a landscape. This approach is expected to provide useful knowledge to inform land use decision-making. However, the knowledge about the spatial distribution of ecosystem service values in Biosphere Reserves and the usefulness of this knowledge for practitioners remains scarce. Through the application of Public Participation Geographic Information Systems (PPGIS) in the Kristianstads Vattenrike Biosphere Reserve located in Southern Sweden, this study identifies i) hotspots and ii) bundles of ecosystem service values, as well as iii) spatial patterns of ecosystem service values regarding the three Biosphere Reserve management zones. Complementary, this study assesses the potential usefulness of the PPGIS-derived knowledge by analyzing qualitative data from a workshop with practitioners of the Kristianstads Vattenrike Biosphere Reserve. My findings reveal distinct patterns of ecosystem service values across Kristianstads Vattenrike Biosphere Reserve that reflect the Biosphere Reserve zones’ management goals. The ecosystem service values were clustered around wetlands and the densest populated areas. Respondents mapped predominantly places for outdoor recreation, biodiversity, and places with existential value. The results highlight the importance of cultural and regulating ecosystem services to people in the Biosphere Reserve. Additionally, practitioners involved in Biosphere Reserve management emphasized the potential strategic usefulness of the PPGIS knowledge for their nature restoration work.
282

An ecosystem service approach to inform reactive nitrogen management in the lower Yakima River Basin, Washington

Crowell, Morgan 03 November 2012 (has links)
Spatially explicit ecosystem service valuation (ESV) allows for the identification of the location and magnitude of services provided by natural ecosystems to human activities along with a measure of their significance based upon economic valuation. While ESV has been used to provide new insight into land use management, few studies have identified the connections between the values of ecosystem services and ecological sensitivity to nitrogen loading despite a growing body of ecosystem service literature. This research combines a GIS-based, value transfer approach to map ecosystem services in the Lower Yakima River Basin (LYRB), Washington, USA, along with estimates of nitrogen loading to identify how nitrogen management may affect ecosystem services in the basin. This analysis combines values of ecosystem services with estimates of nitrogen loading and identifies subwatersheds and specific parcels within a Groundwater Management Area (GWMA) most susceptible to reductions in ecosystem services due to excess nitrogen loading. Based on the benefit transfer analysis, wetlands and forested areas have disproportionately high values of ecosystem services when compared to their land area in the LYRB, while pasture and cultivated crops contribute much less to the total value of ecosystem service flows in proportion to the total area in the LYRB. Across the study area estimated nitrogen loads are strongly driven by the location of concentrated animal feeding operations (CAFOs) and cultivated crops. Areas of particularly high nitrogen loading and high ESV may highlight specific areas for achieving immediate success in increasing or maintaining ecosystem services through appropriately focused regulatory mechanisms. The land cover analysis however, completely neglects the values and importance of subsurface processes and groundwater resources in ecosystem service assessment, and therefore an econometric model is applied to estimate willingness to pay (WTP) to maintain safe nitrate levels in private wells. Through the incorporation of WTP estimates for groundwater quality, a more complete economic and ecological perspective on the effects of landscape N loading in the study site is highlighted. The results of these estimates clearly indicate that ecosystem services from groundwater should be considered to have significant value in the LYRB. Further economic valuation data on specific land cover types and the value of groundwater quality, whether from primary studies or meta-analysis, is needed to refine relative measures of ecosystem service values and more confidently describe these values in specific dollar amounts. Additionally, limits in spatial data resolution may contribute to errors in location and magnitude of ecosystem services, and is an area in need of further development. Despite these potential limitations, this analysis highlights a promising direction for combining spatially explicit ecosystem service valuation with nutrient loading data to identify the location and potential magnitude of effects on ecosystem services from management practices. / Graduation date: 2013
283

En kartläggning av ekosystemtjänster kring Södra Munksjön och appliceringen av grönytefaktor i Jönköping / A mapping of ecosystem services in Södra Munksjön and the application of green area ratio in Jönköping

Garneij, Cecilia, Johansson, Patricia January 2017 (has links)
Syfte: Städer behöver grönska, ekosystem och ekosystemtjänster. Grönytefaktor (GYF) är ett verktyg som säkerställer grönska i urbana miljöer. Jönköpings kommun ska som del i sin stadsutveckling av Södra Munksjön inkludera GYF i sin grönstrukturplan. För att utforma en GYF-modell måste man veta platsens förutsättningar och målbilden för staden. Denna studie syftar till att kartlägga de ES som finns i området idag samt vilka som bör skapas, skyddas, stärkas eller rent av skippas i den nya stadsdelen. Vidare studeras även hur den lokala GYF-modellen kan användas i andra områden i Jönköpings kommun. Metod: En kvalitativ studie har genomförts med hjälp av metoderna litteraturstudie, dokumentanalys, observation och intervjuer. Med utgångspunkt i Ekosystemtjänster i stadsplanering - en vägledning framtagen av ℅ city har ekosystemtjänster identifierats. Intervjuer har genomförts med landskapsarkitekter som arbetat med GYF i sammanhang som liknar det Södra Munksjön och Jönköpings kommun står inför. Resultat: Kartläggningen av ekosystemtjänster i Södra Munksjön visar att de flesta tjänsterna på ℅ citys lista kan identifieras och att de kulturella tjänsterna bör premieras i den GYF-modell som ska utformas för området. För att den lokala GYF-modellen ska kunna appliceras på andra områden underlättar det om modellens formuleringar är generella och kompletteras med separat platsspecifik information. För att GYF ska ge bra resultat är dock uttalade och formulerade mål att styra mot den viktigaste faktorn. Konsekvenser: Genom god planering kan en och samma lösning gynna flera ekosystemtjänster samtidigt, vilket rekommenderas i stadsmiljö. Slutsatsen är därför att fokus bör ligga på kulturella ekosystemtjänster och mångfunktionalitet som resulterar i att alla tjänster gynnas. Då GYF är ett nytt verktyg för Jönköping är det av stor vikt att inkludera berörda aktörer och byggherrar i ett tidigt skede. Begränsningar: Den kartläggning av ekosystemtjänster som gjorts i Södra Munksjön har utgått från en geografisk plats och dokument knutna till denna vilket gör att resultatet är begränsat till Södra Munksjön. Av den analys och diskussion som förs gällande hur en GYF-modell kan tas från ett aktuellt område till att appliceras på andra platser kan dock tas vidare av städer som planerar att använda GYF eller vill utveckla en befintlig GYF-modell. / Purpose: Cities need greenery, ecosystems and ecosystem services. Green area ratio (GAR) is a tool that ensures greenery in urban environments. As a part of its urban development of the new city area Södra Munksjön the municipality of Jönköping will include GAR in the local plan for green structure. In order to design a GAR model, one must know the conditions of the site and vision of the city. This study aims to map the ecosystem services located in the area today as well as the ecosystem services that can be created, protected, strengthened or skipped in the new city area. Furthermore, it is also investigated how the local GAR model can be used in other areas in Jönköping municipality. Method: A qualitative study has been conducted with the help of literature studies, document analysis, observation and interviews. With starting point in the model of guidance on ecosystem services in city planning from ℅ city ecosystem services has been identified. Interviews have been conducted with landscape architects with experience from working with GAR in a context similar to the one in Jönköping. Findings: The mapping of ecosystem services in the area of Södra Munksjön shows that most services from ℅ city can be identified and that the cultural ecosystem services should be premiered in the GAR model designed for the city area. In order for the local GAR model to be applied in other areas, it's easier if the formulations in the model are general and supplemented with separate site-specific information. However, in order for GAR to produce good results the most important factor is to have stated and well formulated goals to aim for. Implications: Through good planning, one solution can benefit several ecosystem services at the same time, which is recommended in urban environments. Thus the conclusion is that focus should lay on cultural ecosystem services and multi-functionality that result with all services benefiting. Since GAR is a new tool for Jönköping, it is of great importance to include stakeholders and building contractors at an early stage. Limitations: The mapping of ecosystem services made in Södra Munksjön has been based on a geographical location and documents linked to this place, which means that the results are limited to Södra Munksjön. However, the analysis and discussion of how a GAR model can be taken from a current area to be applied elsewhere could be taken on by cities that are planning to use GAR or want to develop an existing GAR model.
284

Utvärdering av urbana ekosystemtjänster: Verktyg och certifieringssystem. / Assessment of Urban Ecosystem Services: Tools and Certification Systems.

Lindgren, Sofia January 2013 (has links)
Denna rapport behandlar utvärdering av urbana ekosystemtjänster på stadsdelsnivå. Eftersom ökad urbanisering leder till ökad belastning på urbana ekosystem är det viktigt att både exploatering och etablering av grönområden sker på ett hållbart sätt där ekologiska, sociala och ekonomiska faktorer inkluderas. Detta kan delvis uppnås genom att villkor i verktyg och certifieringssystem inkluderar aspekter för urbana ekosystemtjänster. Det undersökts hur certifieringssystemen BREEAM Communities och CASBEE for Urban Development samt verktyget Grönytefaktormetoden behandlar sådana urbana ekosystemtjänster. Analysen utgår från en föreslagen kategorisering av urbana ekosystemtjänster. Detta kompletteras med ett eget ramverk som utvidgar och förtydligar otillräckligt hanterade ekosystemtjänster och närliggande aspekter. Resultatet visar att ytterligare ekosystemtjänster kan inkluderas i de undersökta metoderna och en kategorisering av urbana ekosystemtjänster förslås. / This report discusses assessment of urban ecosystems services in the scale of city districts. Since intensified urbanisation increases the pressure on urban ecosystems it is of importance that development projects in green areas is sustainable with inclusion of ecological, social and economic aspects. This can in part be achieved through requirements in tools and certification systems that include aspects for urban ecosystem services. An investigation of how the certification systems BREEAM Communities and CASBEE for Urban Development as well as the tool Grönytefaktormetoden deal with such urban ecosystem services is made. The analysis is based on a suggested categorisation of urban ecosystem services. This is complemented by an own framework that expands and clarifies insufficiently treated ecosystem services and adjacent aspects. The result shows that further ecosystem services can be included in the investigated methods and a categorisation of urban ecosystems services is suggested.
285

Investigations on Urban Ecosystem Services provided by Urban Parks and Interactions with Dwellers in the center city of Shanghai, China

Zhao, Liang 21 July 2016 (has links) (PDF)
Under global urbanization backgrounds with physical population migrations and relocations, corresponding consequences in society developments, cultural transformations, technology inventions and interactions between regions and countries, etc. are considered as having a huge impact on normal urban dwellers. For human beings always have intentions towards managements and benefits from natural surroundings, urban dweller demands under the modern challenges and their interactions are necessary to be concerned about. Urban ecosystem is considered as a highly developed civilization, but also with features of resources and energy demands and pollution and distributional exports. As the only natural element in this ecosystem, UGI (urban green infrastructures) is considered as an important human-environment interaction provider with urban ecosystem services (UES) largely focused by academic scholars, urban planners and policy managers. As one of the fastest urbanizing cities in the world, Shanghai is considered as having huge cultural and social developments combined with socioeconomic acceleration. Under the unique background of policy planning and traditional Confucian culture transformation, the impacts to urban dweller demands, whether these newly developed modern demands can be satisfied by UES provided by UGI and how the understandings of these normal dwellers to UGI in Shanghai are necessary for academic researches. By considering the interactions with urban dwellers, six urban parks in the center of Shanghai are chosen as research sites in this study. Combined with factors of urbanization processes and observed patterns of visitor interactions, the indicator of “park age” is concerned with three old parks (older than 25 years old) and three new parks (younger than 25 years old). With methodologies of fieldwork mapping, questionnaires, indicator based evaluation system constructions, etc., the quantitative and qualitative analyses were carried out to habitat diversity, cultural and regulation UES results, and the background reasons caused by political and financial influences are subject to further discussion. The visitors to urban parks of Shanghai are classified into four sorts: “retired dwellers”, “dwellers for children care”, “tourist visitors” and “other visitors”, we found out that related demands and interactions with urban parks have significant differences. After detailed discussions, it could be figured out that the visitors demands play a significant role, and the interactions between visitors and UES in Shanghai are comprehensively influenced by multiple factors of “visiting objectives”, “park cultures (ages, popularities, etc.)” and “personal identities (educations, incomes, etc.)”. Based on this, the detailed differences of policy, finance, Confucian culture, nature understanding, and community society between old and new parks were further discussed. With all aspects of physical, mental, psychological and other demand aspects especially focused on, the typical features in Shanghai are also highly concentrated on dominant activities. For China is suffering from national environmental and urbanization problems but lack in related concerns combined with dweller demands, this research work may make certain efforts on model assessment methodologies constructions and national implementations. Also, with a combined background of top-down policy systems and natural understandings under socioeconomic duress, this research could also make significant efforts in dweller-UES interactions researches in similar cases of other countries and newly developed urban ecosystems in the world.
286

An integrative approach to assess urban riparian greenways potential: The case of Mapocho River in Santiago de Chile

Vásquez, Alexis 19 December 2016 (has links) (PDF)
Santiago is the 7th largest major city of Latin America with almost 8 million inhabitants and is situated in a fairly closed watershed, surrounded on the eastern side by the high Andean mountain chain with altitudes of 5,000 m. From the Andean mountains, the Mapocho River and a set of large and small streams transport -often torrentially- water and sediment. In thirty years, Santiago has increased its size two fold, replacing previous agricultural lands, native forests and shrubs with urban land uses, and occupying rivers beds and streams. These land use and cover changes have had dramatic environmental consequences. The mentioned urban dynamic has produced a city in constant collision with the natural system. This structural disarticulation produces many environmental problems such as an increase in city’s surface and air temperatures, an accelerated disappearance of vegetation, a major interruption in wind, sediment and water flows, and finally, increasing people’s exposure to environmental hazards. Since streams, canals and rivers are structural components of Santiago’s landscape, they can function as key links between the urban-social and natural system and provide multiple ecosystem services, helping to reduce environmental problems and ensure long-term urban sustainability. Traditionally, the analysis of river and streamsides has been focused on rural and natural landscapes as well as on environmental protection and nature conservation. Nowadays, there is an increasing interest and necessity to understand the environmental status, functions and possibilities of riparian zones in urban environments in order to delineate and plan greenways, which provide social and ecological benefits. Green infrastructure such as urban greenways is a key component of sustainable cities. Few studies have been conducted to evaluate the socio-ecological status of urban riparian zones and even fewer to assess these areas in terms of their potential as multifunctional greenways. New efforts should be conducted to develop analytical application-oriented frameworks in the green infrastructure field. This research elaborates and proposes a transferable conceptual-methodological framework for evaluating the potential for multifunctional riparian greenway development. An analytical application-oriented framework to assess the potential for multifunctional green infrastructure development is proposed by articulating and improving three analyses hitherto used separately: multicriteria, least cost path and opportunities-challenges. The Mapocho River was selected for the application and testing of the proposed conceptual-methodological framework to contribute to multifunctional green infrastructure planning in Santiago as a city representative of the structure and processes of megacities in Latin America. First, the main ecological and social characteristics of the Mapocho’s riparian zone are analyzed, making a synthesis of the socio-ecological status. Second, the suitability to provide multiple ecosystem services of the riparian zone is spatially explicitly modelled, first separately, as mono-functional suitability, and then, integrated into a multifunctional suitability evaluation. Third, the opportunities and challenges perceived by government actors are identified and analyzed as well as those derived from an institutional and regulatory analysis. Finally, the assessment phase concludes with a discussion on the main potential for the development of a greenway, resulting from the synthesis and integration of the most relevant findings of the suitability and opportunities analysis The socio-ecological status of the riparian zones is characterized by being highly altered in ecological terms, diverse in social terms, and highly used by the metropolitan transport infrastructure with a concentration of green areas in a few municipalities. This means that the riparian zone provides limited physical support for important social and ecological functions characteristic of these zones in urban environments: habitat, aesthetic, cooling, transport route and flood mitigation. The results reveal a significant east-west gradient in the socio-ecological status of riparian zone, which gradually decreases from east to west. The riparian zone of the Mapocho River in Santiago has good suitability as a wind corridor, providing a cooling effect and to mitigate flood hazards. The main challenges for the development of a multifunctional urban greenway in the Mapocho River corresponds to low levels of inter-jurisdictional and inter-sectoral coordination and cooperation, maintenance costs and the existence of urban highways in the zone. On the contrary, the main opportunities are the existence of important sectors of vacant land, increased political and social importance of urban green areas and the existence of a set of consolidated riparian parks. In synthesis, the assessment developed in the Mapocho River identifies the most important aspects to be considered and the greatest potentialities to capitalize in planning a multifunctional greenway along the Mapocho River. This is key when thinking about a possible master plan for the Mapocho River that returns the river to the city and values it as an axis for urban integration. The development of a multifunctional greenway in Santiago can considerably contribute to the social and ecological connectivity and thereby mitigate the socio-ecological segregation and disconnection characteristic of cities in the region. It may also contribute significantly to reconcile urban growth with ecological health and people’s quality of life, maintaining functions and key ecosystem services and mitigating the negative effects of urbanization.
287

Community-Based Developmental Entrepreneurship: Linking Microfinance with Ecosystem Services

Shahidullah, AKM January 2016 (has links) (PDF)
This research examined whether microfinance-assisted developmental mechanisms can integrate ecological objectives alongside social and economic ones—thus promoting sustainability. The specific focus was to test the ability of microenterprises operated by community-entrepreneurs in supporting local ecosystem services. To this end, the research: elucidated the nature and dynamics of linkages between communities and the local ecosystems with the lens of coupled social-ecological systems, i.e. illustrated ecological modernization of microenterprises in a developing country context; tested how community-based enterprises transform upon application of green microfinance strategy; and then recognized how social learning is promoted through such community-based intervention mechanisms, e.g. microfinance. The research used case study and participatory approaches. The case study comprised two components: i) a green microfinance program, and ii) communities in a riparian, and a wetland ecosystem in Bangladesh engaged in entrepreneurship. The major tools that the study employed for data collections were: household surveys, participatory land -use surveys, semi-structured interviews, key informant interviews, focus group discussions, multi-stakeholder workshops, field observations, and document reviews. The research findings reveal that the green microfinance strategy, in the short and medium terms, catalyzes entrepreneurial and social innovations, and combine the embedded economic and social objectives of the classic microfinance with the new ecological objectives towards sustainability. The strategy applied by Microfinance Institution (MFI) and adopted by community enterprises transformed the ventures—helping them to go green and reducing greenhouse gas emission. Besides, the partnerships that occur between non-governmental organization (NGO) and community-based organization (CBO) in the process of implementing developmental programs—result social learning and innovations in the communities. The research review found grassroots developmental initiatives as an evolving phenomenon over time. With this view, and with its observation through this cross-sectional study, the research proposes a framework entitled ‘community-based developmental enterprise (CBDE)’. The framework proposes community level entrepreneurial ventures, associated NGO-MFIs, CBOs and other development partners to consider ecosystem services and wellbeing components in entrepreneurial design and actions. / October 2016
288

The impact of ecosystem services knowledge on decisions

Posner, Stephen Mark 01 January 2015 (has links)
The need to protect diverse biological resources from ongoing development pressures is one of today's most pressing environmental challenges. In response, "ecosystem services" has emerged as a conservation framework that links human economies and natural systems through the benefits that people receive from nature. In this dissertation, I investigate the science-policy interface of ecosystem services in order to understand the use of ecosystem service decision support tools and evaluate the pathways through which ecosystem services knowledge impacts decisions. In the first paper, I track an ecosystem service valuation project in California to evaluate how the project changes the social capacity to make conservation-oriented decisions and how decision-makers intend to use ecosystem services knowledge. In a second project, I analyze a global sample of cases and identify factors that can explain the impact of ecosystem services knowledge on decisions. I find that the perceived legitimacy of knowledge (whether it is unbiased and representative of many diverse viewpoints) is an important determinant of whether the knowledge impacts policy processes and decisions. For the third project, I focus on the global use of spatial ecosystem service models. I analyze country-level factors that are associated with use and the effect of practitioner trainings on the uptake of these decision support tools. Taken together, this research critically evaluates how ecosystem service interventions perform. The results can inform the design of boundary organizations that effectively link conservation science with policy action, and guide strategic efforts to protect, restore, and enhance ecosystem services.
289

From individuals to ecosystems : a study of the temporal and spatial variation in ecological network structure

Henri, Dominic Charles January 2014 (has links)
Ecological network theory has developed from studies of static, binary trophic relationships to the analysis of quantitative, dynamic communities consisting of multiple link-types. Particularly, work has focused on the dynamic nature of ecological networks, which maintains stability in complex communities. However, there are few in situ network-level studies of the determinants of temporal and spatial variation in community structure. This thesis utilises data from a 10-year study of a host-parasitoid network and a collaborative study in an applied ecological setting to identify individual level factors important to network structure. The work aims towards an empirical, predictive framework linking adaptive foraging behaviour to ecological network structure. The results show that condition-dependent foraging behaviours structure host-parasitoid networks. The realised niches of the studied parasitoid species were generally biased towards larger host species and condition-dependent sex ratio allocation increased the likelihood that females would eclose from relatively larger hosts and males from relatively smaller hosts, which resulted in sex ratios deviating from Hamiltonian (50:50) predictions. Further, both of these aspects of behaviour are plastic, where parasitoid behaviour responded to environmental heterogeneity. Particularly, host preference behaviour conformed to an egg-/time-limitation framework, where the size dependency of the behaviour is greater when individuals have a greater likelihood of being egg-limited. Both the size-dependency and the plasticity of these behaviours differed significantly between secondary parasitoid species. This species identity effect interacted with landscape heterogeneity, which may explain some inter- and intra-specific variation in network structure. With respect to applied ecology, the results show that the benefits of natural vegetation for pest control are dependent upon the dispersal capabilities and the diet breadth of the pest and its natural enemies. The findings are evaluated towards a predictive framework for understanding the effects of future climate change on community structure and stability. We consider this framework in terms of applied ecology, particularly pest control ecosystem services provided by natural vegetation in an agricultural environment. The synergistic nature of the multiple determinants of network structure found in this thesis suggest that future studies should focus on the whole network, which is not necessarily the sum of its parts.
290

Characterization of microbial communities in Technosols constructed for industrial wastelands restoration / Caractérisation des communautés microbiennes dans les technosols construits pour la restauration des friches industrielles

Hafeez, Farhan 06 September 2012 (has links)
L'augmentation de la dégradation des sols et ses conséquences sur les services écosystémiques nécessite le développement de stratégies de restauration de ces sols. La constitution de Technosols, résultant de l’assemblage de sols pollués et de déchet industriels, est une approche innovatrice pouvant à la fois permettre de restaurer les sols et de recycler des sous-produits industriels. Des études récentes ont mis en évidence que les Technosols pouvaient assurer des services écosystémiques tels que la production primaire. Toutefois, notre connaissances des autres services écosystémiques rendus par les Technosols tels que les cycles biogéochimiques est limitée. En raison de la contribution significative des communautés microbiennes aux cycles biogéochimiques dans les sols, l’objectif de ce travail de thèse était l’effet du type de Technosol sur les communautés microbiennes et plus particulièrement les communautés fonctionnelles impliquées dans le cycle de l’azote. Dans ce contexte, (i) la densité et la diversité de la communauté bactérienne totale, (ii) la densité de la communauté crenarchéenne ainsi que (iii) la densité et les activités des communautés nitrifiante et dénitrifiante ont été étudiées dans deux types de Technosols différents. Les résultats obtenus montrent que la diversité et la composition de la communauté bactérienne des deux Technosols n'étaient pas significativement différentes entre elles, et similaires à celles de ‘sols naturels’, les Proteobacteria étant le phylum dominant (50-80%). La densité de la communauté bactérienne oxydant l’ammonium était non seulement plus importante que celle des crenarcheae qui oxyde l’ammonium, mais est également corrélée avec l'activité potentielle de nitrification suggérant ainsi que les bactéries sont responsables de l’oxydation de l’ammonium dans les Technosols. La densité des dénitrifiants et de la communauté oxydant l’ammonium sont du même ordre de grandeur que celles observées dans les sols agricoles. L’analyse de la distribution de l'activité et de la densité des communautés nitrifiante et dénitrifiante dans les différents horizons des Technosols montre un effet négatif de la profondeur, cet effet étant plus marqué que l’effet du type de Technosol étudié. Les propriétés physico-chimiques des Technosols et la densité de la communauté bactérienne oxydant l’ammonium sont corrélés à l'activité de nitrification alors que l'activité de dénitrification était contrôlée principalement par les propriétés physico-chimiques des Technosols, et dans une moindre mesure par la densité de la communauté dénitrifiant possédant le gène nirS. L'estimation de la stabilité fonctionnelle du processus de dénitrification vis-à-vis de périodes stress hydrique et thermique a montré que les Technosols présentaient une plus haute résistance et une meilleure résilience que des sols remédiés par traitement thermique uniquement. Ce travail souligne le potentiel des Technosols à assurer les services écosystémiques tels que le cycle de l’azote, ainsi que leur forte capacité à résister et à se remettre de stress environnementaux. Tout ceci semble donc indiquer que la construction de Technosols est une technologie prometteuse qui pourrait permettre la restauration de friches industrielles et le recyclage des déchets industriels / Increasing soil degradation and its consequences on overall ecosystem services urge for restoration strategies. Construction of Technosols through assemblage of treated soil and industrial wastes is an innovative technology for the restoration of polluted land and re-use of industrial by-products. Recent studies have evidenced that Technosols could support ecosystemic services such as primary production but the knowledge about other soil functions, such as biogeochemical cycling, is limited. Due to the significant contribution of microbial communities to soil functioning, this PhD work was carried out to study the effect of the type of Technosol on microbial communities with a focus on functional guilds involved in N cycling. For this purpose, the abundance and diversity of the total bacterial community and the abundance of crenarchaeal community together with the abundance and activities of the nitrifying and denitrifying communities were investigated in two types of Technosols. Results demonstrated that diversity and composition of the bacterial community were similar to ‘natural soils’ and were not significantly different between the two Technosols with Proteobacteria being the dominant phylum (50-80%). The bacterial ammonia oxidizers were greater in number than crenarchaeal ammonia oxidizers but also correlated to the potential nitrification activity suggesting that bacteria are the dominant ammonia oxidizers in Technosols. The abundance of both the ammonia oxidizers and the denitrifiers were in the same range than that observed in other soil systems. Analyses of the vertical distribution of the activity and abundance of N-cycling communities in the Technosols showed a significant depth-effect, which was more important than the Technosol type-effect. Technosols physicochemical properties and the abundance of the bacterial ammonia oxidizers were the main drivers of the nitrification activity whereas the denitrification activity was controlled mainly by the Technosols physicochemical properties and, to a minor extent, by the abundances of the nirS denitrifiers. The estimation of the functional stability of the denitrification process against the heat-drought stresses revealed that Technosol exhibited the high resistance and resilience in comparison to the thermally treated soil. This work highlighted the potential of constructed Technosols to ensure the N cycling ecosystem services, along with a high capacity to resist and recover from environmental stresses, suggesting that construction of Technosols is a promising technology and a solution for the restoration of industrial wastelands and waste recycling

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