Dissertations / Theses: 'Ecosystem resiliency'

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Kalk, Hannah June. "The role of coastal plant community response to climate change: implications for restoring ecosystem resiliency." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/theses/742.

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Accelerated sea-level rise and increased intensity of tropical storm events have challenged the conventional approaches to conservation and restoration of coastal ecosystems. In coastal communities, where survival will depend largely on the ability of species to adapt to rapidly shifting conditions or become established farther inland, historic assemblages may be lost. Seed banks may be an important component of resilience and recovery in response to altered inundation regimes, should they contain species able to adapt or migrate inland. This study assess the ability of seed banks to act as ecological buffers to storm surge disturbances and to instill ecological resilience in degraded and vulnerable coastal ecosystems. Above-ground, seed bank and propagule assemblages were surveyed from historic communities at the Grand Bay National Estuarine Research Reserve. Artificial storm surge experiments revealed that that seed banks were not well distributed throughout the coastal transition communities and that seed bank responses following storm surges are likely to vary among the different plant communities. While some relict species are expected to respond following disturbances, ruderal species are especially dominant in the upland seed bank communities and may, at least in the short term, cause shifts away from the historical assemblages. The apparent absence of seaward species in the upland seed banks may make assisted migration an important tool for the survival of communities unable to keep pace. Community response following translocation of propagule bank application onto highly degraded buyout properties suggested that this technique may be an effective tool in introducing resilience into ecosystems already experiencing the effects of climate change. They resulted in the establishment of diverse and variable communities, containing indicator species from a number of historic communities with varying environmental tolerances. Long-term monitoring of community change and reproductive output of target species may indicate the utility of community translocation in creating resilient and future-adapted communities.

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Dubickas, Kate M. "Zooplankton Community Structure in the NE Gulf of Mexico: Impacts of Environmental Variability and the Deepwater Horizon Oil Spill." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7780.

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In the northeastern Gulf of Mexico, relating changes in zooplankton communities to environmental factors is crucial to understanding the marine ecosystem and impacts of perturbations such as oil spills on marine ecosystems. Zooplankton samples were collected each year between 2005–2014 in spring and summer in the vicinity of the oil spill (Deepwater Horizon) that occurred in spring 2010. Zooplankton assemblages and environmental conditions significantly differed seasonally, driven by strong variations in zooplankton at continental shelf stations, and by environmental factors including Mississippi River discharge, wind direction, temperature, and chlorophyll concentrations. Total zooplankton abundances were greatest at shelf stations, intermediate at slope stations, and lowest at offshore stations. Seasonal separation was driven by greater abundances of crab zoea, cladocerans, ostracods, and the copepod, Eucalanus spp. during summer. Copepods, Centropages spp., were significant indicators of summer conditions both before and after the oil spill. Sub-regional comparisons in percent composition and abundances of six major non-copepod and seven copepod taxa revealed that most taxa either remained the same or significantly increased in abundance following the spill. A significant decrease in post oil spill taxa was observed only during spring for total copepods, Eucalanaus spp., and for salps at continental slope stations, however varying processing techniques used for zooplankton before and after the spill were employed and should be considered. . Based on our sampling periods, these results indicate that the 2010 oil spill did not significantly impact zooplankton communities in the northeastern Gulf of Mexico.

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Milton, Ashley D. "Forest resilience for livelihoods and ecosystem services." Thesis, George Mason University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3720748.

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Deforestation in the Congo Basin is altering the natural functioning and services of the ecosystem and adversely impacting highly vulnerable human populations who rely on their proper functioning. There is currently no framework that comprehensively addresses the historical and cultural complexities that are persistent in Central African societies and that also include, from a micro scale, the detailed voices of local communities. Without such a holistic framework, it is difficult to evaluate the effectiveness or harmfulness associated with current management strategies in responding to deforestation at the various levels. This transdisciplinary mixed method study determined the most salient indirect and direct causes of forest loss, the impacts resulting from an altered state, and the effectiveness of current management responses by assessing changes in forest cover, forest provisions, and trends in forest management. Because forests are common goods, the elasticity of forests are dependent on a multitude of human activities and attitudes. Therefore, data collected via survey tools were used to evaluate the role of multiple stakeholders in the state of the Congo Forest using the Driver-Pressure-State-Impact- Response (DPSIR) framework, a structured analytical tool created by the European Environmental Agency for better understanding of Integrated Environmental Assessments. To best explore local to international perspectives on the effectiveness of current strategies in sustaining forests for livelihoods and ecosystem services, research methods included conducting remote sensing analysis of Landsat satellite images, interviewing over 325 individuals living in 25 communities in the Lake Télé-Lake Tumba Landscape of northwestern Democratic Republic of Congo and 20 individuals working on forest management, conservation, and funding, and a climate analysis using 40 years of weather data collected from a scientific reserve located within the landscape. Results highlight that local populations are highly environmentally literate and their knowledge is a useful tool for qualifying environmental changes, such as reduced lake health, animal health, and plant health. Remote sensing results show the forest is in a state of decline and climate findings confirm the ecological health of the landscape has been reduced demonstrated by major shifts in the traditional agricultural calendars and the effects are having adverse public health impacts on local communities. The process of this research itself interfaces science and policy and thus recommendations focus on how to make effective payments to communities for supporting alternative livelihoods in order to prevent deforestation while next steps should focus on the implications of forest loss and the promotion of a One Health approach at the landscape level.

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Davis, Zachary Edward. "Toward A Healthcare Services Ecosystem." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/82853.

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This research examines the healthcare services ecosystem and the impact and role service interventions made by providers and patients have on this ecosystem. Each area has an important role in contributing to the value and sustainability of the ecosystem. Healthcare, as a community service, requires a minimum of two counterparts: the providers and the customers, in this case the patients. Healthcare is a unique ecosystem because often the customers are not conscious of the interplay of the ecosystem but are reliant upon the system for their health and wellbeing. The first section of this dissertation examines the effects that occur in the healthcare ecosystem when part of the system experiences a disaster and the impact and role of other areas of the system in response to the disaster, particularly regarding the resilience. Similar to a biological ecosystem that is undergoing a flood, in the healthcare services ecosystem if too many patients present to the Emergency Department (ED) at the same time disaster level overcrowding will occur. We aim to measure the resilience of the healthcare ecosystem to this disaster level overcrowding. The second section of this dissertation examines how the components of the healthcare ecosystem maintain sustainability and usability. Healthcare professionals are assessed regarding their ability to maintain the healthcare ecosystem, with a specific focus on what occurs after patients are in the hospital system. To examine the ability of the healthcare professionals to maintain the ecosystem we analyze the usability and adaptability of the electronic health record and the professional's workflows to determine how they use this tool to sustain the healthcare ecosystem. The third section of this dissertation examines patient self-management and the influence this has on the healthcare ecosystem. Much of the management of health in patients, particularly those with chronic illnesses, occurs outside of the hospital, thus examining this aspect of self-care provides insight on the overall system. This research examines patients with a chronic illness and their use of online health communities, with a particular focus on their reciprocal behaviors and the impact this support system has on their overall health state. By examining these aspects of the healthcare services ecosystem, we can better improve our understanding of these phenomena.
Ph. D.

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Ford, Paulette Louise. "Scale, ecosystem resilience, and fire in shortgrass steppe." Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/289192.

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Consideration of scale and ecosystem resilience is integral to any conceptual model of the effects of disturbance on ecosystems. Organisms, populations, communities, and ecosystems are differentially affected by disturbance based on the scale at which they occupy the landscape. Scale of observation influences perceptions about ecosystem resilience. There is no single correct scale at which ecological phenomena should be studied, and management decisions require the interfacing of phenomena that occur on very different scales of space and time. Fire disturbance affects a variety of ecosystem factors including nutrient cycling, species diversity, and population and community dynamics. My experimental research on fire in shortgrass steppe examined the effects of fire and season of fire on various components of shortgrass steppe at multiple spatial and temporal scales and organizational units. My experimental design was completely randomized, with 3 treatments, and 4 replicates per treatment. Treatments were dormant-season fire, growing-season fire, and unburned. Response variables were (1) ground cover; (2) microbiotic crust nitrogen fixation, and chlorophyll a content; and (3) species richness, abundance, and relative abundance of small mammals and arthropods. Microbiotic crust cover never differed significantly among treatments for all periods, however, acetylene reduction and chlorophyll a content of crusts differed significantly among treatments. Dormant-season fire-treated crusts had significantly lower rates of acetylene reduction than unburned crusts, while growing-season fire-treated crusts did not differ significantly from unburned or dormant-season fire-treated crusts. Dormant-season fire-treated crusts had significantly lower chlorophyll content than unburned crusts, while growing-season fire-treated crusts did not significantly differ from unburned or dormant-season fire treated-crusts. Initially, growing-season fire significantly reduced grass cover compared to unburned and dormant-season fire. Approximately 30 months later there were no significant differences in grass cover among treatments. Bare ground response was basically the inverse of grass cover response. The only significant differences in litter cover between treatments occurred immediately after the growing-season fire. Arthropod species richness differed significantly among treatments; growing-season fire plots had a significantly higher number of beetle species. However, overall beetle abundance did not significantly differ among treatments. Significant differences were never detected in overall rodent species richness or abundance among treatments.

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Leftwich, Samuel Joseph. "The resilience of forests to the urban ecosystem." Cleveland State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=csu1631645306327862.

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Sanmartí, Boixeda Neus. "Biological interactions and resilience of seagrass ecosystems." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/672259.

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Our world is subjected to a panoply of drivers of change. In this context, the understanding on how our biosphere resists, absorbs or is altered by the changes, appears as a hot question in ecology. In this respect, two ecological concepts appear as essential, resilience and biotic interactions. Resilience is related to how ecosystems persist under stress or suffering disturbances. Interactions among species are to a large part responsible for the delivery of ecosystem functions, and form the architecture of biodiversity. Moreover, a substantial part of ecosystem resilience is founded on species interactions. This thesis is an attempt to shed some light on these issues through the deep exploration of specific case studies in seagrass ecosystems, in particular how seagrasses respond to external drivers (or how resilient they are), how these responses affect species interactions and which mechanisms allow coexistence of species linked by positive and negative interactions. Our approach is based upon field observations and field manipulative experiments. Chapter 1 shows how an increase of organic matter in sediment weakens the mutualism between the bivalve Loripes lucinalis and the seagrass Cymodocea nodosa. The mechanism implied is the effect of this increase (and, probably, the resulting anoxia) on seagrass root morphology (plant trait), which results in a lower provision of habitat for the bivalves, whose abundance decreases. The weakening of the mutualism can potentially decrease the resilience of these ecosystems to eutrophication and, therefore, compromise their persistence. Chapter 2 describes a facilitative cascade in which the seagrass C. nodosa favors the abundance of the pen shell Pinna nobilis, which positively affects the sea urchin Paracentrotus lividus, which in turn consumes the seagrass. We suggest that the persistence of this three-species assemblage rests on the very local impact of sea urchins on the seagrass, likely driven by behavioural and denso-dependent processes. Chapter 3 and 4 show that fast-growing species such as C. nodosa are highly resilient to stress or disturbances when affecting only the aboveground parts, recovering fast (within two weeks) from a single event of disturbance. C. nodosa shows several mechanisms of tolerance, such as compensatory growth, reallocation of internal resources and enhancement of the formation of new modules, when coping to repeated defoliation simulating herbivory. However, when the belowground parts are lost by disturbances, recovery is highly delayed up to two years and is dependent on the characteristics of the disturbance such as size and timing. Overall, this research has contributed to increase our understanding on how ecosystems respond to changes and how species interactions are maintained and disrupted. We have shown that environmental changes can alter the functioning of seagrass ecosystems at least in two directions. Firstly, by altering fundamental biological interactions, such as the seagrass-lucinid mutualism and, secondly, by affecting the resilience of ecosystems dominated by a foundation species, which promote species coexistence. Advances in the two complementary and interlinked directions will be crucial to better manage and preserve ecosystems and prevent their potential collapse under the increasing human-induced change the world is submitted to.
El nostre món està sotmès a un ampli ventall de forces que tendeixen a provocar canvis. En aquest context, entendre com la biosfera resisteix, absorbeix o és alterada per aquestes forces resulta una qüestió candent, especialment per l'ecologia. Al respecte, dos conceptes ecològics esdevenen essencials: la resiliència i les interaccions biològiques. La resiliència és la capacitat de persistència o recuperació que tenen els ecosistemes sotmesos a estrès o pertorbacions. Les interaccions entre espècies (efectes de l'existència d'una espècie sobre la fitness d'una altra) contribueixen al manteniment de les funcions ecosistèmiques i, en un cert sentit, constitueixen l'arquitectura de la biodiversitat. A més, la resiliència dels ecosistemes depèn , en gran part, d’aquestes interaccions. Aquesta tesi és un intent d’aprofundir en els aspectes esmentats a través d'una sèrie de casos d’estudi en ecosistemes d’angiospermes marines. Concretament, el que fem és estudiar com els ecosistemes d’angiospermes marines responen a les forces causants de canvis, com aquestes respostes vénen mitjançades per canvis en la interacció entre espècies, i provar d'esbrinar els mecanismes que permeten la coexistència d’espècies que es troben vinculades per interaccions positives i negatives. La nostra aproximació es basa tant en observacions com en experiments en el camp. El Capítol 1 mostra com un increment de matèria orgànica en el sediment debilita el mutualisme entre el bivalve Loripes lucinalis i l’angiosperma marina Cymodocea nodosa. El mecanisme implicat que es proposa per explicar-ho està relacionat amb la plasticitat morfològica de la planta. Així, un increment en la matèria orgànica del sediment (i, probablement, l’anòxia que se'n segueix), fa que la planta modifiqui la morfologia de les seves arrels, que esdevenen molt menys ramificades i fan disminuir per tant la disponibilitat d'hàbitat per als bivalves. Una debilitació del mutualisme pot, potencialment, disminuir la resiliència d’aquests ecosistemes a l’eutrofització i, per tant, comprometre la seva persistència. El Capítol 2 descriu una cascada de facilitació en la qual l’angiosperma marina C. nodosa afavoreix l’abundància del gran bivalve Pinna nobilis, que ajuda a incrementar l'abundància de la garota Paracentrotus lividus, que al seu torn consumeix l’angiosperma. Suggerim que la persistència d’aquest sistema de tres espècies, aparentment inestable (tres interaccions concatenades circularment, dues de positives i una de negativa) es basa en què la interacció negativa (l’efecte de les garotes sobre l’angiosperma) té un abast molt limitat, probablement degut tant al seu comportament alimentari com a les defenses de la planta enfront de l'herbivorisme. Els Capítols 3 i 4 mostren que les espècies de creixement ràpid, com ara C. nodosa, són altament resilients a l'estrès o a les pertorbacions quan aquestes afecten només les parts aèries de les plantes (defoliació parcial o total), recuperant-se ràpidament (dues setmanes) després d'una pertorbació puntual en el temps. C. nodosa mostra diversos mecanismes de tolerància a la defoliació, com ara el creixement compensatori, la reassignació de recursos interns i l’increment en la taxa de formació de nous mòduls. Tanmateix, quan les pertorbacions provoquen la pèrdua de les parts subterrànies (rizomes i arrels), la recuperació és molt més lenta, i triga fins a dos anys. A més, aquesta recuperació depèn de les característiques de la pertorbació com ara la mida de l'àrea afectada i l’època de l'any en què es produeix. En general, aquesta tesi ha contribuït a comprendre millor les respostes dels ecosistemes als canvis. Hem pogut documentar alguns processos que permeten la coexistència entre espècies, així com mecanismes de resiliència específics que esdevenen ecosistèmics quan es manifesten en espècies fundadores d'hàbitat. També hem demostrat com els canvis, més enllà d'afectar espècies individuals més o menys emblemàtiques, poden provocar alteracions de formes més subtils, com ara erosionant la seva resiliència mitjançant la modificació d’interaccions biològiques. Els avenços en totes aquestes direccions complementàries i interrelacionades són crucials per a gestionar i preservar els ecosistemes i evitar el seu possible col·lapse.

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Oswald, David. "Estimating resilience of Amazonian ecosystems using remote sensing." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18801.

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A model for ecological resilience of Amazonian ecosystems was developed integrating processes such as atmosphere-biosphere coupling with disturbance factors such as fire and climate change. The focus of the study was on the status of ecosystems in the state of Mato Grosso and the possibility of forest to savannah transition was examined using remote sensing data. There was a consistent reduction in EVI during the dry season in Mato Grosso – May through August of each year. The 2005 drought demonstrated a greater dry-season reduction in EVI than normal and there was also a higher frequency of fires (48, 682) than in 2006 (28, 466). There was an increase in fires with distance from the major highways – which is contrary to the results of previous studies. It was estimated that there was a reduction in the amount of forest ecosystems from 2001 to 2006.
Un modèle de résilience écologique de l'écosystème amazonien a été développé, intégrant des processus tels que le couplage atmosphère-biosphère avec des facteurs de perturbation tels que le feu et les changements climatiques. L'objectif de cette étude était d'évaluer l'état des écosystèmes dans l'état du Mato Grosso. Une possible transition de la forêt à la savane a été examinée en utilisant des données de télédétection. Il y a eu une réduction de l'EVI pendant la saison sèche dans le Mato Grosso, de mai à août pour chaque année d'étude. La sécheresse de 2005 a provoqué une réduction de l'EVI plus importante que la normale, en plus d'augmenter la fréquence des feux (48, 682) par rapport à 2006 (28, 466). Il y a eu une augmentation des incendies avec la distance par rapport aux principales autoroutes, ce qui est contraire aux résultats des études précédentes. Il a été estimé qu'il y a eu une réduction du nombre d'écosystèmes forestiers entre 2001 et 2006.

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Peter, Hannes. "Diversity and Ecosystem Functioning : Redundancy and Resilience in Freshwater Bacterial Communities." Doctoral thesis, Uppsala universitet, Limnologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160780.

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Bacteria are immensely diverse and hold key-positions in essentially all biogeochemical cycles. In freshwater ecosystems, bacteria degrade and mineralize organic compounds, linking the pool of dissolved organic matter to higher trophic levels. Aware of the global biodiversity loss, ecologists have started identifying the relationship of diversity and ecosystem functioning. Central to this is the question if species can functionally replace other species, hence being functionally redundant. Functional redundancy might allow communities to maintain functioning when diversity is lost. Due to their large numbers and great diversity, bacterial communities have been suspected to harbor large amounts of redundancy. The central aim of this thesis is to investigate the coupling of diversity and ecosystem functioning of bacterial communities and to understand how environmental perturbation affects this relationship. I manipulated the diversity of complex communities by a dilution technique, and measured the performance of bacterioplankton and biofilm-forming communities at different diversities. Reduction of bacterial diversity differently affected different functions, and that the presence or absence of certain species might be causing this pattern. However, for ecosystems to function, the interplay of multiple functions, i.e. multifunctionality, has to be sustained over long periods of time. In bacterial biofilm communities reduced diversity affected multifunctionality, as reflected by extracellular enzyme activities. A continuous cultivation system was used to address the importance of diversity for resistance and resilience upon environmental perturbation. The analysis of co-occurrence of bacterial taxa showed that the communities form a dense network before the perturbation and that these patterns are disturbed by the environmental perturbation. The final chapter of the thesis presents experimental evidence for the positive effects of temporal and spatial refuges for bacterial communities and the functions they provide. Overall, I found several indications for a lower amount of functional redundancy as previously assumed and it becomes apparent from this thesis that a multifunctional perspective and the consideration of environmental heterogeneity is pivotal.

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Strunz, Sebastian [Verfasser], and Stefan [Akademischer Betreuer] Baumgärtner. "Ecosystem resilience as an economic insurance / Sebastian Strunz. Betreuer: Stefan Baumgärtner." Lüneburg : Universitätsbibliothek der Leuphana Universität Lüneburg, 2012. http://d-nb.info/1034194852/34.

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Uy, Noralene Menchavez. "Ecosystem-based Adaptation Planning to Strengthen Disaster Resilience in Infanta, Philippines." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/175209.

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Duncan, C. A. "Mangrove forest ecosystem services : biodiversity drivers, rehabilitation and resilience to climate change." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1553177/.

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Mangrove forests provide a significant contribution to human well-being; particularly through climate change mitigation and adaptation (CCMA) due to disproportionately high carbon sequestration and coastal protection from tropical storms. However, mangrove community structure drivers of these ecosystem services (ES), rehabilitation potential for high CCMA ES delivery, and their resilience to climate change impacts remain poorly understood and monitored. This thesis uses field- and satellite remote sensing-based methods and a dual focus at a Philippines-specific and West Africa to South Asian-scale to quantitatively assess mangrove CCMA ES delivery. The first three chapters provide a background, and literature review on ES delivery, ecological restoration and resilience to perturbations, mangrove ES, their anthropogenic and climate change threats, and current management. Chapters 4 and 5 detail the case study selection and methodologies employed. Chapter 6 focuses on the flora community structure drivers of mangrove ES delivery, and shows that divergent controls can drive trade-offs in the delivery of key CCMA benefits. Chapter 7 focuses on the potential of mangrove rehabilitation for high CCMA ES delivery, and shows that mangrove rehabilitation in abandoned aquaculture ponds can provide high relative CCMA benefits, revealing large areas of abandoned aquaculture with favourable tenure status for greenbelt rehabilitation. Chapter 8 focuses on remote monitoring of mangrove resilience to sea level rise, and the potential anthropogenic and abiotic factors influencing these, establishing a methodology for continued remote monitoring and revealing variability in resilience and resistance across forests. Overall, it is demonstrated that current mangrove management in the Philippines and globally may be insufficient to secure high CCMA ES delivery, due to (1) non- consideration of flora community structure, site-specific and areal requirements, (2) complexity in governance systems for reclamation of mangrove lands, and (3) a lack of spatial planning and zoning to accommodate mangrove resilience to climate-induced perturbations.

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Kjellberg, Eric, and Daniel Oldenmark. "Ecosystem Goal Alignment and Institutional Change : Increasing Resilience and Competitiveness in Värmland." Thesis, Karlstads universitet, Handelshögskolan (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-85432.

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Economy professor Kjell Nordström argued at the Nordic Business forum Sweden, that regions such as Värmland would turn into wastelands in the aftermath of digitalization and urbanization. Digitalization has rapidly changed service provision effecting the provider-user interaction and service options available. To stay competitive, a sustainability report on the region recommends local actors to find common goals to enhance the value-proposition providing advantages not offered by larger elsewhere controlled or e-commerce actors. Previous studies regarding value co-creation conclude that due to macro level influences such as digitalization, a systemic approach is vital. Hence, this thesis uses a service ecosystem, approach addressing the problem and research inquiries regarding relationship market influence in and among various levels and relationship construction for mutual member goals capturing value. The aim of this thesis is to explore how actors can increase their resilience towards macro level influences. The empirical data was gathered through conducting a qualitative exploratory case study using non-probability sampling to map the service ecosystem around a resilient actor. The data collection comprised of field observation, a brief document analysis and seven semi-structured interviews. Five interviews with different actors supported by two interviews with key customers. The data was processed and thematically analyzed through coding and grouping. Findings was then compared to the theoretical framework and discussed in relation to the background and problem. The study concluded that actors were unable of making an impact individually and essentially need goal alignment for institutional change. However, depending on actor size, type, level of digitalization, and market aim, the importance varies. Actors primarily targeting a regional market were considered dependent on goal alignment and institutional change for resilience. By accomplishing collective goals ecosystem members indirectly achieve individual goals increasing competitiveness, enhancing the business climate. Through institutional change members counteract and restructure the ecosystem adjusting to macro level changes affecting the meso and micro interaction creating resilience.

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Oh, Yu Kyung. "Climate change adaptation in London through resilient ecosystem services management." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/climate-change-adaptation-in-london-through-resilient-ecosystem-services-management(c1b8b3aa-04d5-4151-83da-9971ed59f95f).html.

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As urban populations continue to grow around the world, cities and their residents become increasingly vulnerable to climate change risks. Detrimental impacts on natural ecosystems have been observed in the built environment, as well as poorer quality of life. As urban areas are characterised by complex adaptive systems, the concept of ecosystem services represents an important tool for the management of urban socio-environmental quality and can be applied to climate change adaptation and mitigation strategies. This thesis investigates London’s potential resilience to climate changes through ecosystem services management. In particular, the socioecological capacity of the All London Green Grid for contributing to climate change resilience via patterns of green spaces, and carbon storage and sequestration through urban street trees, will be the central focus in the research. This capacity was assessed firstly by conducting an evaluation of the landscape metrics of Greater London’s green spaces to determine the extent and quality of green infrastructure, and how this varies according to relevant socioeconomic variables. This was achieved using GIS and the spatial analysis programme FRAGSTATS. This broad-scale evaluation was then supported by greater in-depth field measurements, focusing specifically on street trees, within selected eleven Business Improvement Districts (BIDs), which are an important vehicle for the local management of the ALGG and thereby climate resilience. This local-scale assessment also incorporated greater evaluation of ecosystem service provision by vegetation, and in particular street trees and their capacity for carbon storage and sequestration. Finally, governance of green spaces within BIDs and broader understanding of resilience and climate change was assessed with qualitative research methods, including semi-structured interviews of different agents and agencies involved in the ALGG network. This included investigation of decision-makers’ perspectives on vulnerabilities and the prospects for further developing London green spaces, to determine the feasibility of different management options.

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Moore, Jonathan Richard. "Aspects of land surface modelling : role of biodiversity in ecosystem resilience to environmental change and a robust ecosystem demography model." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/22649.

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Earth's species are disappearing at a rate unprecedented in human history, yet whether this loss will make the ecosystem "services" that support our civilisation more vulnerable to environmental change is poorly understood. This thesis investigates two different aspects of land surface modelling. It firstly models the role of biodiversity in ecosystem resilience using the Lotka-Volterra and single resource models to model diversity using competition coeffcients, stochastic noise and evolution inspired trait diffusion and then examines if higher diversity makes these simple models more resistant to temperature increases. It secondly develops a theoretical plant demography model, based on the continuity equation, to robustly represent forest size diversity. This avoids both the complexity and maintainability issues seen in Forest Gap models and improves the representation of land use and land cover change and of regrowth time-scales after disturbance, which can be unrealistic in some of the previous generation of Dynamic Global Vegetation Models (DGVMs), such as TRIFFID (Cox et al., 2001). While the Lotka-Volterra with competition coeffcients and the single resource with stochastic noise approaches are found to be impractical, the single resource model with trait diffusion successfully shows that higher diversity requires a faster critical rate of temperature change before system net primary productivity (NPP) collapses. The continuity equation model of vegetation demography is solved analytically with the size dependence of the growth rate approximated first by a power law and then with a quadratic. The power law solution can be reduced to a "self-thinning" trajectory, and the quadratic solution gives either a rotated sigmoid or 'U-shape' distribution of plant sizes, depending on the ratio of mortality to maximum growth gradient. The model is then extended to produce the basis of a new Dynamic Global Vegetation Model (DGVM) called "Robust Ecosystem Demography" (RED), adapting the plant physiology from TRIFFID DGVM to generate a size-dependent growth function. A proportion of the NPP from this growth is used for reproduction and the shading is modelled simply by random overlap. The model is found to better represent regrowth time-scales compared to TRIFFID and is also found to demonstrate an optimum proportion of NPP to reproduction which decreases with plant lifetime.

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Clay, Larry Clinton Jr. "Integrative Ecosystem Management: Designing Cities and Co-creating the Flourishing Ecosystem." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case162584034740029.

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Berg, Alicia. "Empowering the Steel Industry as a Stakeholder : Environmental Management and Communication through a Social-Ecological Approach." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-91102.

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This paper explores a case study of a Swedish tool steel company undergoing a transition from traditional environmental management practices to an enterprise identifying its place as part of a social-ecological system. The Corporate Ecosystem Services Review (ESR) was utilized by the company to begin this process by focusing on ecosystem services to determine how an ESR approach contributes to environmental management in practice. What resulted moved beyond the ESR to a tailored methodology, the internalization of a systems perspective, and a proposed new environmental management system. The results of the study provide a concrete, effective method for internalizing a systems perspective through a focus on ecosystems and presents a case for further analysis into what made it successful. It also provides an example of translating theory into practice, illustrating how a company can engage in sustainable development by valuing and managing the resilience of social-ecological systems through identifying their place in that system. The value of the results can be high for the case study company as well as for business in general.

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18

Rajarshi, Dasgupta. "Enhancing Coastal Community's Disaster and Climate Resilience in the Mangrove Rich Indian Sundarban." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215362.

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19

Evans, Paul M. "Dynamics of forest ecosystem properties and resilience in a temperate woodland undergoing dieback." Thesis, Bournemouth University, 2018. http://eprints.bournemouth.ac.uk/30829/.

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Given that woodland disturbance events are expected to become more frequent and severe in the future, it is crucial to understand how fundamental underlying ecosystem properties (EPs) including biodiversity, ecosystem functions and ecosystem services will be impacted. Currently, this knowledge is severely limited, but is essential for future management of forests at both stand and landscape scales. The impact of such disturbances on EPs can be quantified through the use of ecological resilience and its associated concepts. Resilience relates to either the amount of disturbance an ecosystem can endure and still exist or the degree to which an ecosystem can resist or recover from disturbance. Resilience concepts of ecological thresholds, points of abrupt change in an EP, and resistance, persistence and recovery time are useful metrics to determine disturbance impacts. Moreover, using knowledge of how EPs are affected by disturbance, resilience assessments can enable inference of the current level of resilience that woodland has. The objectives of this thesis were therefore: 1) to determine how biodiversity, ecosystem functions and condition were affected in a forest undergoing dieback; 2) to examine the effectiveness of rapid condition assessment tools as a proxy use for inferring woodland resilience; and 3) to determine whether woodland cover influences resilience of EPs at a landscape scale. The changing condition and extent of the New Forest provided an opportunity to measure EPs across a gradient of changing condition. This was carried out through gradient analysis of dieback, based on basal area decline, at the stand scale. Using the results obtained from the gradient analysis: i) the resilience of important woodland EPs was assessed at the landscape scale using simulations of different intensities of disturbance and woodland cover, which was used as a proxy for connectivity; and ii) commonly-used forest condition assessment tools, specifically airborne lidar and the woodland Common Standards Monitoring condition assessments, were tested to determine how effective they were and whether they could be used to infer resilience at the stand scale. Overall, evidence provided in this thesis suggests that: biodiversity and functional thresholds exist as the forest degrades; current condition assessment tools are not very effective at detecting variation in woodland condition and therefore are not sufficient to infer current resilience; and woodland cover influences the resilience of important woodland EPs, at the landscape scale. All the findings are discussed in context of the New Forest, an ecologically and socio-economically important landscape.

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Wilkinson, Cathy. "Social-ecological resilience and planning: an interdisciplinary exploration." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-78977.

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Despite considerable expansion in the scope and function of the state with respect to environmental protection, the world’s biological diversity and ecosystem services continue to deteriorate. Finding ways to better govern human-nature relations in cities is an important part of addressing this decline. The aim of this thesis is to explore the potential of social-ecological resilience to inform urban governance in theory and practice, through a focus on strategic spatial planning. Resilience has become an increasingly important urban policy discourse and much hope is placed in its potential to improve urban governance. However, there is an acknowledged gap between social-ecological resilience as an ideal and the ability to govern towards it in practice. At the time this doctoral research commenced there had been no engagement with social-ecological resilience in the planning theory literature and minimal engagement by empirical planning research. It is to this gap the thesis contributes. Social-ecological resilience scholarship is found to offer planning theory a partly new way of understanding complex human-nature relations. This is relevant to calls by planning theorists for more attention to matters of substance, including ecological processes. With respect to practice, planners see potential for social-ecological resilience to critically inform strategic spatial planning, including through the framing of problems, tools for analysis/synthesis and governance options. There are also however, lessons for social-ecological resilience scholarship that emerge from the detailed empirical research which suggests that attention to the politics of the everyday activities of administrators, elected officials, planning officials, conservationists and citizens operating within the so-called ‘mangle of practice’ is critical to explaining the gap between the ideal of governing for urban resilience, and what happens in practice.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript.

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21

Rosenberg, Barbro. "The Role of Ecosystem Services for a Resilient Urban Agriculture System : Case Studies from the Stockholm Region." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299522.

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Just like in the rest of the world, the urban population in Sweden is increasing each year, which means that cities are becoming increasingly densified and natural green areas are claimed and used for built environment. As a result, biodiversity in cities is often low and inhabitants risk facing losses of ecosystem services of various kinds. As a counterforce to these challenges linked to urbanization, urban agriculture has become an increasingly popular and growing phenomenon in Sweden in recent years. Researchers have begun to recognize the potential of urban agriculture to address the issues of urban green spaces, food security and social interaction between different cultures in cities. Despite the growing interest in urban agriculture, there seems to be a lack of empirical studies examining the potential of urban agriculture to contribute ecosystem services to cities. The aim of this thesis is thus to investigate and map ecosystem services from urban agriculture systems and perform a resilience analysis to assess the opportunities and challenges associated with the management and development of ecosystem services from urban agriculture. To do this, a case study was performed on two different types of urban farms located in the Stockholm region. The study was delimited to look at regulating, provisioning, and cultural ecosystem services from urban agriculture for commercial use in Stockholm. Moreover, the study applied a qualitative and semi-quantitative research method where the collection of data material was based on a literature study, semi-structured qualitative interviews, and observations. A resilience analysis of the empirically collected data material was performed using seven principles as a framework. These principles have been presented in previous research and are shown to have important links to the management of ecosystem services. The results of the study show that commercial urban agriculture in Stockholm has great potential to contribute with ecosystem services to the city as the two investigated cases contribute with regulating, provisioning, and cultural services of various kinds. The studied outdoor farm was shown to contribute with 26 different ecosystem services, while the studied indoor farm in greenhouse was shown to contribute with 9. Furthermore, the study indicates that the two studied cases are, at present, not independent of external systems as they, among other things, require some inputs to maintain respectively cultivation activities. From a resilience perspective, the study indicates that many activities that are currently carried out in the studied urban farms contribute to strengthening the resilience of the produced ecosystem services. Examples of this are that they actively work for knowledge development, participate in research projects, integrate systems and risk thinking and involve a varied range of actors in their businesses. However, the study also suggests that challenges to strengthen resilience exists and look different in the two different urban farms. For the outdoor farm, it is indicated that the biggest challenges are related to financial aspects, as this is an obstacle to launching more ideas related to agriculture activities and thus also an obstacle to increasing the diversity of ecosystem services. For the indoor farm in greenhouse, on the other hand, challenges related to infrastructure and the dependence on a stable electricity supply to strengthen resilience through diversity of ecosystem services are emphasized. Finally, it can be stated that cooperation between actors at different levels is an important factor for the development of urban agriculture and for the resilience of the ecosystem services produced.
Precis som i resten av världen ökar den urbana befolkningen i Sverige varje år, vilket innebär att städerna blir alltmer tätbebyggda och grönområden tas i anspråk för att ge plats åt bebyggd miljö. Till följd av detta är den biologiska mångfalden i städer oftast låg och den urbana människan riskerar att gå miste om ekosystemtjänster av olika slag. Som motkraft till dessa utmaningar kopplade till urbanisering har stadsodling kommit att bli ett alltmer populärt och växande fenomen i Sverige under de senaste åren. Forskare har börjat erkänna potentialen för stadsodling att ta itu med frågorna om urbana grönområden, livsmedelssäkerhet och social interaktion mellan olika kulturer i städerna. Trots det ökande intresset för stadsodling tycks det finnas en brist på empiriska studier som undersöker stadsodlingens potential att bidra med ekosystemtjänster till städer. Syftet med detta examensarbete är således att undersöka och kartlägga ekosystemtjänster från stadsodlingssystem samt utföra en resiliensanalys för att bedöma de möjligheter och utmaningar som är förknippade med förvaltning och utveckling av ekosystemtjänster från stadsodling. För att göra detta utfördes en fallstudie på två olika typer av stadsodlingar belägna i Stockholmsregionen. Studien avgränsades till att undersöka reglerande, försörjande och kulturella ekosystemtjänster från stadsodling för kommersiellt bruk i Stockholm. Vidare tillämpade studien en kvalitativ och semi-kvantitativ forskningsmetod där insamling av datamaterial baserades på en litteraturstudie, semistrukturerade kvalitativa intervjuer och observationer. En resiliensanalys av det empiriskt insamlade datamaterialet utfördes genom att använda sju principer som ramverk. Dessa principer har presenterats i tidigare forskning och visats ha viktiga kopplingar till förvaltning av ekosystemtjänster. Studiens resultat visar att kommersiell stadsodling i Stockholm har stor potential att bidra med ekosystemtjänster till staden då de båda undersökta fallen bidrar med reglerande, försörjande och kulturella tjänster av olika slag. Den studerade utomhusodlingen visades bidra med 26 olika ekosystemtjänster, medan den studerade inomhusodlingen i växthus visades bidra med 9 stycken. Vidare indikerar studien att de båda undersökta fallen i dagsläget ej kan vara oberoende av externa system då de bland annat kräver en del insatsmedel för att upprätthålla respektive odlingsverksamhet. Utifrån ett resiliensperspektiv indikerar studien att många aktiviteter som idag utförs i de undersökta stadsodlingarna bidrar till att stärka resiliensen av de producerade ekosystemtjänsterna. Exempel på detta är arbete för kunskapsutveckling, deltagande i forskningsprojekt, integrerade system- och risktänkanden samt involverande av flertalet aktörer. Däremot antyder studien även att utmaningar för att stärka resiliensen dess mer finns, och ser olika ut i de två olika odlingssystemen. För utomhusodlingen indikeras att de största utmaningarna är relaterade till finansiella aspekter, då detta är ett hinder för att sjösätta fler idéer relaterade till odlingsaktiviteter och därmed även ett hinder för att öka mångfalden av ekosystemtjänster. För inomhusodlingen i växthus, å andra sidan, framhävs utmaningar relaterade till infrastruktur och beroendet av stabil elförsörjning för att stärka resiliensen genom mångfald av ekosystemtjänster. Slutligen kan konstateras att samarbete mellan aktörer på olika nivåer är en viktig faktor för utvecklingen av stadsodling och för resiliens hos de producerade ekosystemtjänsterna.

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Kristensen, Nadiah Pardede. "Goal functions and ecosystem contraints : thermodynamic goal functions, local stability, maximal resilience, and permanence /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18700.pdf.

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Longo, Marcos. "Amazon Forest Response to Changes in Rainfall Regime: Results from an Individual-Based Dynamic Vegetation Model." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11268.

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The Amazon is the largest tropical rainforest in the world, and thus plays a major role on global water, energy, and carbon cycles. However, it is still unknown how the Amazon forest will respond to the ongoing changes in climate, especially droughts, which are expected to become more frequent. To help answering this question, in this thesis I developed and improved the representation of biophysical processes and photosynthesis in the Ecosystem Demography model (ED-2.2), an individual-based land ecosystem model. I also evaluated the model biophysics against multiple data sets for multiple forest and savannah sites in tropical South America. Results of this comparison showed that ED-2.2 is able to represent the radiation and water cycles, but exaggerates heterotrophic respiration seasonality. Also, the model generally predicted correct distribution of biomass across different areas, although it overestimated biomass in subtropical savannahs.
Earth and Planetary Sciences

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24

Waters, James. "The role of ecosystem services and adaptive capacity in the resilience of poor urban areas." Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/48094/.

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This thesis aims to understand the important features of resilience for individuals living in poor urban areas. There is currently little understanding of the role of ecosystem services, or the key components of adaptive capacity in these areas. As urbanisation continues apace, it is of utmost importance that we understand how to build resilience in slums and informal settlements. This thesis contributes to this challenge by finding determinants of adaptive capacity, the degree to which ecosystem services are used, and significant heterogeneities in slum adaptive capacity. The research is based on empirical fieldwork in three slum areas in Kampala, Uganda. Study areas were chosen at differing distances from the city centre to the periphery, with data collected at the individual level. Mixed methods were used and included pre-study open interviews, a random survey questionnaire, and focus groups. A total of 720 questionnaires capture the bulk of the information, and contain two relatively novel methods – a presentation of adaptive capacity statements, and a social network analysis. The thesis finds that slum residents use local ecosystem services very little but where there are green spaces, they are valued for benefits such as recreation or aesthetics. Slum residents tend to deal with problems with the help of others, and social networks are critical for adaptive capacity. Other significant determinants of adaptive capacity include innovation, feelings of control, and a sense of place. There are significant differences in adaptive capacities and social networks between slums areas, and specific population groups. These results give policy key features of resilience to build on, and highlight the importance of assessing where strengths and weaknesses lie. The determinants of resilience in poor urban areas are unique, but once understood, enable us to reduce vulnerability for a vast proportion of the world's population living in slums and informal settlements.

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Lindström, Robin. "Flexibility or coerced resilience: Analysing the role of flex crops in the global production ecosystem." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-194678.

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Large parts of Earth’s natural ecosystems have been converted into simplified production system. These production systems, named the Global Production Ecosystems (GPE) are characterised by homogenised and industrial production, that delivers predictable yields of biomass and is highly connected through global trade. The anthropogenic inputs required to keep this predictability is likely to cause environmental degradation and could cause novel risks in the long term. The rise of flex crops is a phenomenon that is likely to further promote this homogenisation and industrialisation. These are crops with multiple and flexible uses that are increasingly targeted by agribusinesses to feed the demands of food, feed, fuel and other industrial products. This study examines global flex crops production ecosystem through the lens of resilience thinking, by analysing production data over time, including the social and environmental impacts of inputs, and assess the national concentration of production. I find that flex crops have expanded and intensified more so than similar crops. Since 1961 flex crops harvested area have increased in more than 150% in size, while similar crops have increased 10%. At the same time yields for flex crops have almost tripled, while similar crops have doubled their yield. I also find that in some aspects flex crops are heavily reliant on anthropogenic inputs. On a global scale the use of inputs is generally concentrated to a small number of countries, but that the average use of inputs varies greatly between countries. These findings indicate that the development of flex crops is an important to research to understand the GPE and that using resilience thinking is key to understand this phenomenon.

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26

Sadauskis, Rolands. "Building resilience to climate-driven regime shifts." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-64551.

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There is increasing concern about potential climate-driven regime shifts– large abrupt shifts in social-ecological systems that could have large impacts onecosystems services and human well-being. This paper aims to synthesize the potentialpathways for building resilience to such regime shifts. Ten examples from the RegimeShift Database provided the cases for analysis. Causal loop diagrams were used toanalyze feedback mechanisms at different scales and identify “leverage points” –places to intervene in the system in order to build resilience. Sixteen of these leveragepoints were identified, most of which relate to agricultural management. Mostfeedback mechanisms include at least one leverage point highlighting the potential forbuilding resilience to climate-induced regime shifts. The most common leverage pointsidentified in our analyses were vegetation cover, algae volume and atmospherictemperature. These leverage points were compared to mitigation strategies discussedby the IPCC. This comparison indicates that current climate change mitigationstrategies do not alter most of the leverage points directly. This suggests that IPCCstrategies should be broadened in order to reduce the risk of regime shifts, and theassociated impacts on human well-being.

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Ernstson, Henrik. "In Rhizomia : Actors, Networks and Resilience in Urban Landscapes." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8137.

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With accelerating urbanization it is crucial to understand how urban ecosystems play a part in generating ecosystem services for urban dwellers, such as clean water, spaces for recreation, stress relief and improved air quality. An equally important question relate to who gets to enjoy these benefits, i.e. the distribution of ecosystem services, and how issues of power and equity influence the management of ecosystems. Through case studies from the urban landscape of Stockholm, this doctoral thesis engages with these perspectives through combining ecological theory with social theory, including social network analysis, actor-network theory and social movement theory. Strategies for how to improve urban ecosystem management are presented along with frameworks for how to analyze issues of power and equity in relation to natural resource management. Paper I shows that ecosystem management can be studied through analyzing the structure of social networks, i.e. the patterns of relations between agencies, stake-holders and user groups. Paper II and Paper III analyze, based on a network survey of 62 civil society organizations and in-depth interviews, a transformational process of how an urban local movement managed to protect a large urban green area from exploitation (The Stockholm National Urban Park). Paper IV discusses, based on several case studies from Stockholm, a conducive network structure for linking managers and user groups (e.g. allotment gardens, cemetery managers, and urban planners) across spatial ecological scales so as to improve urban green area management. Paper V presents a framework to analyze the social-ecological dynamics behind the generation and distribution of ecosystem services in urban landscapes. The thesis points towards the notion of "a social production of ecosystem services" and argues for deeper engagement with urban political ecology and critical geography to inform governance and collective action in relation to urban ecosystems.

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McDonald, M. Christine, of Western Sydney Hawkesbury University, and Faculty of Agriculture and Horticulture. "Ecosystem resilience and the restoration of damaged plant communities : a discussion focusing on Australian case studies." THESIS_FAH_HOR_McDonald_M.xml, 1996. http://handle.uws.edu.au:8081/1959.7/683.

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An examination was undertaken of the literature and restoration cases for 4 major Australian vegetation types (sclerophyll; rainforest; grassland; and wetland) to explore the proposition that ecological resilience may govern recovery after anthropogenic damage, and/or provide a fundamental guide and measure of success for ecological restoration. Also, primary data were collected from highly degraded sites (5 sclerophyll, 3 rainforest, and 4 grassy sites) to assess recovery after restoration treatment. These were supplemented with questionnaire data from practitioners working at a wider range of rainforest and sclerophyll sites, and reports from practitioners working on grassland and wetland sites. In all 4 vegetation types, species generally fell into two main groups : longer-lived 'resprouters' and shorter-lived 'obligate seeders'. But different resilience models were identified for the 4 vegetation types. The sclerophyll type exhibited higher in situ resilience but lower migratory resilience than the rainforest type, which was facilitated by flying frugivore dispersal to perch trees. Self-perpetuation was more tightly coupled with disturbance in the sclerophyll, grassland and wetland types than rainforest; and therefore 'designed disturbance' played a more obvious role in enhancing recovery within these types, than in rainforest. Results suggest that resilience (as both an ecosystem property and a theoretical concept) is fundamental to the practice of ecological restoration. Some prediction of resilience potential of particular degraded sites (and prediction of the degree and type of restoration subsidy needed) can be based on knowledge of : individual species' recovery mechanisms; resilience models for individual vegetation-types; and the site's colonisation potential and impact history
Doctor of Philosophy (PhD)

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29

Liebergesell, Mario, Björn Reu, Ulrike Stahl, Martin Freiberg, Erik Welk, Jens Kattge, J. Hans C. Cornelissen, and Josep Peñuelas. "Functional resilience against climate-driven extinctions." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-204141.

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Future global change scenarios predict a dramatic loss of biodiversity for many regions in the world, potentially reducing the resistance and resilience of ecosystem functions. Once before, during Plio-Pleistocene glaciations, harsher climatic conditions in Europe as compared to North America led to a more depauperate tree flora. Here we hypothesize that this climate driven species loss has also reduced functional diversity in Europe as compared to North America. We used variation in 26 traits for 154 North American and 66 European tree species and grid-based co-occurrences derived from distribution maps to compare functional diversity patterns of the two continents. First, we identified similar regions with respect to contemporary climate in the temperate zone of North America and Europe. Second, we compared the functional diversity of both continents and for the climatically similar subregions using the functional dispersion-index (FDis) and the functional richness index (FRic). Third, we accounted in these comparisons for grid-scale differences in species richness, and, fourth, investigated the associated trait spaces using dimensionality reduction. For gymnosperms we find similar functional diversity on both continents, whereas for angiosperms functional diversity is significantly greater in Europe than in North America. These results are consistent across different scales, for climatically similar regions and considering species richness patterns. We decomposed these differences in trait space occupation into differences in functional diversity vs. differences in functional identity. We show that climate-driven species loss on a continental scale might be decoupled from or at least not linearly related to changes in functional diversity. This might be important when analyzing the effects of climate-driven biodiversity change on ecosystem functioning.

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Pessot, Olivier. "Small Businesses and how they connect to the Sustainable City : A list of actions for the transformation to a sustainable Paris." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-61674.

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The City relies on Nature‟s products and services for its wellbeing and its very existence. Smallbusinesses, the socio-economic fabric of the City, are mostly mainstream and not engaged insustainability. From their point of view, how do they connect to the Sustainable City?In one of the most competitive areas of central Paris, mainstream businesses and also frontrunners, thelatter already engaged in sustainability, were interviewed as a pilot to further explore transformationinto the Sustainable City. All were asked to reflect on their experience in managing change. They werethen encouraged to propose actions in face of the challenges of sustainability and the sustainable city,and react on a vision of the Sustainable City for Paris and its larger region. They expressed barriers tochallenges and to the vision proposed. And they also proposed ideas, expressed desires, opportunitiesand overall bridges for sustainability to be practically implemented. The findings presented theenterprises‟ interpretation of the concepts of trust and innovation. Reflecting on how the results couldcontribute to a transformation into a Sustainable City resulted in a practical list of actions. This pilotstudy showed a potential for sustainable development to emerge throughout the City through its mostimpactful yet promising actors, the small businesses.In order to contribute in building bridges between City and Nature, the exploration is inspired bysocial ecological research, looking for ways to harmonize the various elements and actors to transformcities into sustainable ones. The framework is mostly based on a business-inspired research design anda construct from the European Union Sustainable City challenges, resilience theory approaches and theFrench national strategy for sustainable development.

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Katycheva, Anna. "From Brownfields to Green Infrastructure : A resilience thinking approach to brownfield transformation." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256313.

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Brownfields have the potential to be transformed to offer green infrastructure to cities and bottom up environmental stewardship approaches can be a creative and dynamic way of providing much needed ecosystem services to the urban environment. The following study explores how the transformation of a contaminated site to a community garden in Stockholm can contribute to providing ecosystem services and improving general resilience. Through aqualitative method including literature review, interviews and observations; the results showed elements contributing to resilience including an increase in the diversity of the urban landscape, the creation of a space for social connections, and a gateway to sharing knowledge and creating polycentricity in natural resource management.
Förorenade områden kan potentiellt omformas för att erbjuda grön infrastruktur till städer och miljöförvaltning kan vara ett kreativt och dynamiskt sätt att tillhandahålla välbehövliga ekosystemtjänster till stadsmiljön. Denna studie utforskar hur omvandlingen av ett förorenat område till en stadsodling i Stockholm kan bidra till att skapa ekosystemtjänster och ökan resiliens i samhället. Genom användningen av kvalitativa metoder – såsom en litteraturstudie, intervjuer och observationer – visar resultaten på en ökad resiliens genom ökad mångfald i landskapet, skapandet av plats för sociala förbindelser, ökad kunskap om ekosystemtjänster samt polycentricitet inom naturresurshantering.

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32

McDonald, M. Christine. "Ecosystem resilience and the restoration of damaged plant communities : a discussion focusing on Australian case studies /." View thesis, 1996. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030625.095246/index.html.

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Laliberté, Etienne. "Land-Use Intensification in Grazing Systems: Plant Trait Responses and Feedbacks to Ecosystem Functioning and Resilience." Thesis, University of Canterbury. School of Forestry, 2011. http://hdl.handle.net/10092/5109.

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Land-use change is the single most important global driver of changes in biodiversity. Such changes in biodiversity, in turn, are expected to influence the functioning of ecosystems and their resilience to environmental perturbations and disturbances. It is widely recognised that the use of functional traits and functional diversity is best for understanding the causes and functional consequences of changes in biodiversity, but conceptual development has outpaced empirical applications. This thesis explores these ideas in grazing systems, which are expected to undergo rapid intensification of fertiliser use and grazing pressure to meet the growing global demand for livestock products. First, a flexible framework for measuring different facets of functional diversity is described, and a new multidimensional functional diversity index, called functional dispersion (FDis), is presented. Second, two vegetation sampling methods are compared with regard to their ability to detect changes in vegetation composition. Third, shifts in plant trait distributions following land-use changes are quantified and compared to null models, and a maximum entropy approach is used to quantify the direction and strength of selection on each trait. Fourth, it is shown that these shifts in trait distributions have cascading effects on primary production, litter decomposition, soil respiration, and ultimately soil carbon sequestration. Finally, data from 18 land-use intensity gradients are used to show that land-use intensification reduces functional redundancy and response diversity, two components of biodiversity that are thought to influence ecosystem resilience to future disturbances. This study illustrates (i) the importance of considering species functional differences to understand how plant communities react to changes in soil resource availability and grazing pressure, and (ii) how such changes directly, indirectly, and interactively control ecosystem functioning, as well as (iii) increasing the vulnerability of ecosystems to future disturbances.

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Boltemo, Edholm Jenny. "How can Ecosystem Services be implemented in local Climate Adaptation? : A case study of Arjeplog." Thesis, Mittuniversitetet, Institutionen för ekoteknik- och hållbart byggande, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-36856.

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Ecosystem services are essential for human climate adaptation. As climate change is a direct driver of change for ecosystem service provisioning, it is of importance to care for our ecosystems to be able to cope with future challenges. Local governance has a central role in climate adaptation due to its responsibility in physical planning. To be able to plan for changes driven by climate change, a flexible, adaptive strategy is necessary. Ecosystem-based Adaptation, EbA, can provide this flexibility to an overall adaptation strategy. In this case study, the potential of EbA to help Nature-based Tourism, NbT, to adapt to a changing climate was spatially mapped to be a useful part of the basis for local physical planning. The mapping includes areas of biodiversity, water infrastructure and features that provide resilience to climate change. The results show that there are areas with potential for EbA that can address adverse effects of climate change for the NbT. These spatial mapped areas provide an instant overview of the key areas to consider when planning for climate adaptation. These mapped areas are also combined with a qualitative assessment of the potential for EbA. By providing decision-makers with information on where and how ecosystem services can assist local climate adaptation, decisions that support both the future of humanity and ecosystems are enabled. However, to reach enforcement of EbA, the knowledge has to be included in binding documents such as detail plans.

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Sundler, Sofie Inger. "Ecosystem Services in Spatial Planning : Towards Sustainable Development in the Swedish Physical Planning Process." Thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-19823.

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This thesis aims at defining the connection between the increasingly popular ecosystem services theory and its practical implications for sustainable development in Swedish physical spatial planning. A literature study was made to summarize the ecosystem services and resilience thinking concepts (with an emphasis on ecosystem services), their definitions and potential uses in physical spatial planning. This overview was then applied in choosing a concept framework to be tested in a case-study: the possible changes in ecosystem services and their values in a land-use trade off situation. To gather insight into the benefits of the ecosystem services concept, compared to environmental integration into physical spatial planning on a municipal level today, the literature study was extended to encompass a short overview of environmental management in the Swedish planning system. Finally, the case study was introduced to municipal employees with strong ties to the planning process, in order to gage their opinions on the ecosystem services concept and its usefulness in planning for sustainability and increased human wellbeing. The results of these interviews showed a generally positive attitude towards the concept as a way to gather and communicate ecological and socio-cultural information to decision makers. The economic valuation was deemed less important as the method is fraught with such difficulties. Overall, the ecosystem services and resilience thinking concepts have great potential to gather the discontinuous environmental management methods toward sustainable (ecologic) development, but in order for this to happen, the municipalities need to be given the right resources, and incentives, for implementation.

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Kleplova, Klara Zoe. "Ecosystem Services Based Evaluation Framework of Land-use Management Options for Dryland Salinity in the Avon Region, Western Australian Wheatbelt." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227654.

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Dryland-salinity management options aim to positively influence the adverse human-induced processes which lead to salinisation of top-soil. Specifically, the processes causing dryland-salinity are rising saline groundwater table and soil erosion. In the Avon region of Western Australia, the management options are evaluated solely on the basis of their efficiency in lowering groundwater tables. However, recently the need to take into account also their wider impact on the ecosystems' resilience has been recognised as well. Nevertheless, the tool to assess these impacts is missing. The aim of this thesis is to synthesise the missing tool from existing ecosystem services-based land-use evaluation frameworks, which would fit the environmental issue, regional socio-economic demands and the existing dryland salinity management options' efficiency evaluation framework. The thesis builds on secondary data and describes (i) the environmental issue of dryland salinity in Australia, (ii) the dryland salinity-environmental, economic, social and political environments of the Avon region, and (iii) five chosen evaluation frameworks which assess the impact of land-use on ecosystem resilience. The proposed optimal framework for the Avon region is then a combination of two existent frameworks: (i) ecosystem resilience evaluation framework & (ii) the ecosystem services economic valuation framework. Where the inputs of the proposed optimal framework are: (i) soil properties, (ii) external natural and anthropogenic drivers and (iii) beneficiaries; the transfer phase is represented by the soil processes; and the output of the framework are (i) ecosystem services and (ii) their economically valued benefits.

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Ahmadi, Behzad. "On the Drought Recovery and Resiliency: How Terrestrial and Riverine Ecosystems Recover from Agricultural and Hydrological Droughts." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/4834.

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Climate extremes, in particular droughts are significant driving forces towards riverine and terrestrial ecosystems disturbance. Drought impacts on stream ecosystems include losses that can either be direct (e.g. destruction of habitat for aquatic species) or indirect (e.g. deterioration of water quality, soil quality, and increased chance of wildfires). This study investigates hydrological and agricultural droughts and their recovery durations. For the riverine ecosystems, this study combines hydrologic drought and water quality changes during droughts and represents a multi-stage framework to detect and characterize hydrological droughts, while considering water quality parameters. Hydrological droughts are categorized into three stages of growth, persistence, retreat, and water quality variables (i.e., water temperature, dissolved oxygen concentration, and turbidity) are utilized to further investigate drought recovery. The framework is applied to 400 streamflow gauges across the Contiguous United States (CONUS) over the study period of 1950-2016. The framework is assessed and validated based on three drought events declared by the state of California in 2002, 2008, and for the 2012 US drought, which affected most of the nation. Results reveal the duration, frequency, and severity of historical droughts in various regions, additionally, duration of each stage of drought (i.e., growth, persistence, and retreat) is also assessed and the spatial patterns are diagnosed across the CONUS. Varied drought recovery durations are perceived for different water quality variables, and in general, it takes about two more months for water quality variables to recover from a drought, following the hydrological drought termination. For the terrestrial ecosystem, this study evaluated drought impacts on gross primary productivity (GPP), evapotranspiration (ET), and water use efficiency (WUE = GPP/ET) of different terrestrial ecosystems over the CONUS, as well as the drought-recovery during the period of 2000 to 2014. The response of WUE to drought showed large differences in various regions and biomes. WUE for arid ecosystems typically showed a positive response (increase) to drought, whereas WUE for humid ecosystems showed both positive and negative response to drought. The results revealed that WUE is correlated with drought severity, and for more severe droughts, WUE changes more significantly. Furthermore, terrestrial drought recovery shows a positive correlation with drought severity and in regions that experienced more severe drought episodes, ecosystem requires longer period to recover.

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Bowditch, Euan A. D. "Walking the land : examining an ecosystem approach for private estates through the lens of woodland expansion." Thesis, University of the Highlands and Islands, 2016. https://pure.uhi.ac.uk/portal/en/studentthesis/walking-the-land(5d6ff0c9-9de5-46d3-a7f2-48b5b8643719).html.

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This thesis presents a local interpretation of an ecosystem approach; 'energyscapes' constructed through mixed methods, which captures private estate manager perception on land use, woodland expansion and collaboration over four case study areas in the Scottish Highlands. Each case study area of three contiguous estates forms a small landscape cluster, with every estate participating in field interviews, woodland planning and collaborative discussions. Private estates in Scotland cover a significant area of the Highlands and are dominated by traditional sporting interests and recreation that is not always considered compatible with woodland expansion, creating a culture of woodland neglect. Subsequently planting rates are falling and Scottish government woodland expansion targets are not being met, despite large areas of vacant land. Key areas of estate and woodland resilience are identified by land managers to improve social and structural connectivity using the novel landscape resilience mapping method, which presents land manager perceptions over a spatial scale linked to resilience concepts. The Forest Energy Tool developed in response to the need for economic justification for woodland expansion demonstrates the potential profitability of local woodfuel markets, as well as providing silvicultural treatments for further management aims. Estate resilience involves fostering effective integration between sporting uses, renewable energy and enhanced rural markets, such as value added forestry. Ecosystem approaches are normally expressed through aspirational policy that is difficult to translate into relevant practice for individual land managers. Energyscapes provides meaning to ecosystem approach policy through CBD principles and operational guidelines, and local practice; including integration of hydro schemes, forest energy and carbon sequestration at estate level and bridging of local and regional scales through six land manager identified landscape partnerships. However, developing leadership, as well as expertise and social capacity in landscape management, is required to mobilise such frameworks. Fundamental to realising these local ecosystem approaches is land manager trust and confidence, which can generate support for emerging land uses alongside tradition, increasing resilience by capturing and utilising the culture embedded within the landscape.

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Villa, Pedro Manuel. "Ecological drivers of tree diversity and ecosystem functioning during succession in Amazon: forest resilience after indigenous shifting cultivation." Universidade Federal de Viçosa, 2018. http://www.locus.ufv.br/handle/123456789/21157.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A floresta Amazônica vem sendo ameaçada pelas mudanças no uso da terra para a expansão da fronteira agrícola, provocando uma simplificação taxonômica e funcional, e em consequência gerando impactos negativos na relação da biodiversidade e funcionamento dos ecossistemas. Assim, o objetivo principal desta pesquisa foi avaliar os efeitos dos modeladores ecológicos sobre a diversidade taxonômica e funcional (alfa e beta) e sua relação com funcionamento ecossitêmico durante a sucessão secundária de uma floresta Amazônica, no estado Amazonas, Venezuela. Por este motivo, esta pesquisa foi dividida em sete capítulos, dois capítulos para descrever os efeitos do padrão de uso da terra sobre a recuperação da diversidade e perda da resiliência florestal, dois capítulos para explicar os efeitos dos modeladores ambientais e antropogênicos sobre a diversidade taxonômica e funcional (alfa e beta) e os efeitos sobre o funcionamento ecossitêmico durante a sucessão, e três capítulos como recomendações para o manejo e conservação de florestas da Amazônia. Utilizamos dados de inventário de plantas de 63 parcelas (1000 m 2 , 20 x 50 m) em seis locais com florestas secundárias de cinco e 10 anos de regeneração depois de um até seis ciclos de agricultura itinerante para avaliar o efeito de diferentes intensidades de uso da terra, bem como a fertilidade do solo na recuperação da diversidade e estrutura da floresta. Também analisamos as mudanças na diversidade e composição das espécies arbóreas após um único ciclo de agricultura itinerante, utilizando dados de 45 parcelas distribuidas em quatro florestas secundárias (5, 10, 15, e 20 anos de idade após do cultivo) e uma floresta madura (> 100 anos). Dentro de cada área de amostragem se estabeleceram três parcelas de 1000 m 2 (20 x 50 m para árvores com DAP > 5 cm). Em cada área foi coletada uma amostra de solo a diferentes profundidades (0-10 cm, 10-30 cm). Assim, analisamos padrões ecológicos e modeladores ambientais da diversidade taxonômica e funcional (alfa e beta), e os efeitos do tempo de sucessão e qualidade do solo (fertilidade e textura) sobre a estocagem de biomassa acima do solo através da diversidade funcional e dominância funcional durante a sucessão secundária. Usamos diferentes métodos estatísticos e tipos de modelos para testar estas relações ecológicas. Neste estudo, demostramos como a intensidade do uso da terra induz uma perda de resiliência florestal, de forma contrária se evidencia que com disturbios intermediários depois de um único ciclo de agricultura ocorre uma rápida recuperação da diversidade, atingindo aproximadamente um 70% da riqueza de uma floresta madura depois de 20 anos. No entanto, a recuperação da composição das espécies nesse mesmo período atingiu uma média de 25% em relação à floresta madura. Nosso estudo mostra que a diversidade beta explica até 70% da variação na riqueza total de espécies entre os sítios, provavelmente devido a que as manchas desmatadas estão inseridas dentro de uma matriz de floresta madura. Este contexto ecológico também justifica o elevado turnover taxonômico durante a sucessão. Assim, a diversidade funcional foi menor do que a diversidade beta taxonômica, provavelmente devido a um menor turnover funcional em comparação com o turnover taxonômico. Nossos resultados proporcionam importantes evidências sobre relação biodiversidade-função ecossistêmica durante a sucessão secundária de uma floresta tropical Assim, os modelos de equação estruturais testados sobre dominância funcional e diversidade funcional, permitiram explicar variações na biomassa acima do solo de forma individual. O tempo de sucessão foi o melhor preditor para explicar variações da biomassa acima do solo em todos os modelos SEM explorados, seguidamente da textura solo que teve afeitos significativos positivos sobre a biomassa acima do solo, em comparação à fertilidade do solo que apresentou efeitos negativos e não significativos. Nosso estudo contribui no entendimento da relação BEF ao longo da sucessão secundária, e pode ajudar a predizer como as florestas tropicais respondarão aos cenários futuros de mudanças climáticas. Por esse motivo, discutimos que para aumentar a eficiência na implementação de estratégias REDD+ em florestas da Amazônia, é necessário compreender simultaneamente a relação de padrões e processos dos ecossistemas florestais com o sistema sócio-ecológico, através da análise de preditores biofísicos e antropogênicos, a partir de um nível local para uma escala regional.
The Amazon forest is being threatened by land use changes for the agricultural expansion, causing a taxonomic and functional simplification, and consequently generating negative impacts on the relation of biodiversity and ecosystem functioning. Thus, the main objective of this research was to evaluate the effects of ecological drivers on taxonomic and functional diversity (alpha and beta) and their relationship with ecosystem functioning during the secondary succession of an Amazon forest, in Amazonas state, Venezuela. For this reason, this research was divided into seven chapters, two chapters to describe the effects of the land use pattern on the recovery of diversity and loss of forest resilience, two chapters to explain the effects of environmental and anthropogenic drivers on taxonomic diversity and functional (alpha and beta) and effects on ecosystem functioning during the succession, and three chapters as recommendations for the management and conservation of Amazonian forests. We used plant inventory data from 63 plots (1000 m 2 , 20 x 50 m) at six sites with five and 10 year regeneration secondary forests after one to six cycles of shifting cultivation to evaluate the effect of different intensities of use land, as well as soil fertility in the recovery of forest diversity and structure. We also analyzed changes in the diversity and composition of tree species after a single cycle of shifting cultivation, using data from 45 plots distributed in four secondary forests (5, 10, 15, and 20 years old after cultivation) and a mature forest (> 100 years). Within each sampling area three plots of 1000 m2 (20 x 50 m for trees with DBH> 5 cm) were established. In each area a soil sample was collected at different depths (0-10 cm). Thus, we analyzed ecological and environmental drivers and patterns of taxonomic and functional diversity (alpha and beta), and the effects of stand age and soil quality (fertility and texture) on the storage of above-ground biomass through functional diversity and functional dominance during the secondary succession. We use different statistical methods and types of models to test these ecological relationships. In this study, we show how the intensity of land use induces a loss of forest resilience. On the contrary, it is evident that with intermediate disturbances after a single cycle of agriculture a rapid recovery of diversity occurs, reaching 70% of the richness of one mature forest after 20 years. However, the recovery of the species composition in the same period reached an average of 25% in relation to the mature forest. Our study shows that beta diversity accounts for up to 70% of the variation in total species richness among sites, probably because deforested patches are embedded within a mature forest matrix. This ecological context also justifies the high taxonomic turnover during the succession. Thus, the functional diversity was lower than the taxonomic beta diversity, probably due to a lower functional turnover in comparison to the taxonomic turnover. Our results provide important evidence on the relation between biodiversity and ecosystem function (BEF) during the secondary succession of a tropical forest. Thus, the structural equation models (SEM) tested on functional dominance and functional diversity allowed to explain variations in the above-ground biomass individually. The succession time was the best predictor to explain above- ground biomass variations in all SEM models, followed by soil texture that had significant positive effects on above-ground biomass compared to soil fertility that had negative effects and not significant. Our study contributes to the understanding of the BEF relationship throughout the secondary succession, and may help predict how tropical forests will respond to future scenarios of climate change. For this reason, we have argued that in order to increase the efficiency in the implementation of REDD+ strategies in Amazonian forests, it is necessary to simultaneously understand the relationship of patterns and processes of forest ecosystems with the socio-ecological system, through the analysis of biophysical and anthropogenic predictors, from a local level to a regional scale.
Tese não possui título em português.

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40

Haber, Lisa T. "Forest Structural Complexity and Net Primary Production Resilience Across a Gradient of Disturbance in a Great Lakes Ecosystem." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5277.

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Forests are an important component of the global carbon (C) cycle and contribute to climate change mitigation through atmospheric C uptake and storage in biomass and soils. However, the forest C sink is susceptible to disturbance, which modifies physical and biological structure and limits spatial extent of forests. Unlike severe, stand-replacing disturbances that reset forest successional trajectories and may simplify ecosystem structure, moderate severity disturbances may instead introduce complexity in ways that sustain net primary production (NPP), leading to the phenomenon of “NPP resilience.” In this study, we examined the linkage between disturbance severity and ecosystem biological and physical structural change, and implications for NPP within an experimentally disturbed forest in northern Michigan, USA. We computed spatially resolved and spatially agnostic metrics of forest biological and physical structure before and 10 years after disturbance across a continuum of severity. We found that while biological structure did not change in response to disturbance, three of four physical structural measures increased or were unimodally related to disturbance severity. Physical structural shifts mediated by disturbance were not found to directly influence processes coupled with NPP. However, decadal changes in the spatial aggregation index of Clark and Evans, though not a function of disturbance severity, were found to predict canopy light uptake, leaf physiological variability, and relative NPP within plots. We conclude that ecosystem structural shifts across disturbance severity continua are variable and differ in their relationship to NPP resilience.

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Morillas, L., R. E. Pangle, G. E. Maurer, W. T. Pockman, N. McDowell, C. W. Huang, D. J. Krofcheck, et al. "Tree Mortality Decreases Water Availability and Ecosystem Resilience to Drought in Piñon-Juniper Woodlands in the Southwestern U.S." AMER GEOPHYSICAL UNION, 2017. http://hdl.handle.net/10150/626564.

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Climate-driven tree mortality has increased globally in response to warmer temperature and more severe drought. To examine how tree mortality in semiarid biomes impacts surface water balance, we experimentally manipulated a pinon-juniper (PJ) woodland by girdling all adult pinon trees in a 4 ha area, decreasing pinon basal area by similar to 65%. Over 3.5 years (2009-2013), we compared water flux measurements from this girdled site with those from a nearby intact PJ woodland. Before and after girdling, the ratio of evapotranspiration (ET) to incoming precipitation was similar between the two sites. Girdling altered the partitioning of ET such that the contribution of canopy transpiration to ET decreased 9-14% over the study period, relative to the intact control, while noncanopy ET increased. We attributed the elevated noncanopy ET in the girdled site each year to winter increases in sublimation and summer increases in both soil evaporation and below-canopy transpiration. Although we expected that mortality of a canopy dominant would increase the availability of water and other resources to surviving vegetation, we observed a decrease in both soil volumetric water content and sap flow rates in the remaining trees at the girdled site, relative to the control. This postgirdling decrease in the performance of the remaining trees occurred during the severe 2011-2012 drought, suggesting that pinon mortality may trigger feedback mechanisms that leave PJ woodlands drier relative to undisturbed sites and potentially more vulnerable to drought.

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Snyman, Elaine. "An exploration of the socio-ecological antecedents of youth resilience : a visual study / Elaine Snyman." Thesis, North-West University, 2012. http://hdl.handle.net/10394/10360.

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The purpose of this study was to identify and understand the social-ecological resources which encouraged resilient Basotho youth in the rural areas of the Thabo Mofutsanyana district of the Free State province towards positive adjustment in the face of poverty and underdevelopment. Positive adjustment, or resilience, is the focus of the International Community-University Research Alliance (ICURA) and International Development Research Centre (IDRC) funded project, called Pathways to Resilience. My study forms part of this broader resilience study. Resilience, or positive adjustment to hardship, can be defined as the capacity of individuals to navigate their way to health-promoting resources that encourage positive adjustment, and the concomitant capacity of the individual’s family, community and culture to provide these health resources and experiences in culturally meaningful ways. Recently, researchers have suggested that the socio-ecological resources that encourage positive adjustment might differ across ecologies. There is little understanding in South Africa of which resources, within specific ecologies, encourage such positive adjustment. My study seeks to address this gap, with specific reference to Basotho youth in the Thabo Mofutsanyana district in the Free State. I used a qualitative phenomenological strategy of inquiry and participatory visual methods to determine the socio-ecological antecedents of the resilience of 130 resilient Basotho youth from rural areas of the Thabo Mofutsanyana district in the Free State province of South Africa. Using Bronfenbrenner‟s Ecological Systems Theory (1979), Sameroff‟s Transactional Model of Development (2009) and Unger’s Social Ecology of Resilience (2011) as framework, I explored the resources underpinning the resilience of my participants. The findings suggest that the resilient Basotho youth in this study were encouraged to adjust well to the risks of poverty and associated threats by making use of social-ecologically accessible resilience-promoting resources. In other words the resilient Basotho youth found resilience-promoting resources in their microsystems (individual, family, school, peers and nature and pets), mesosystems (social interactions), exosystems (community resources like libraries and medical facilities, and role models) and macrosystems (religious beliefs and practices, pastors, and access to information through television, radio, cell phone, and inspirational publications). The conclusion of my study lays emphasis on the interwovenness of socioecological systems in resilience processes: no one system could be sing led out. The entire ecosystem was involved, reciprocally, in providing the participants with resilience-promoting resources. My findings emphasise the importance of mothers, grandmothers, school and educational resources, religious beliefs and practices, and access to information (through the use of television, radio, computer and inspirational literature) for Basotho youth in the Thabo Mofutsanyana district, but do not suggest that these are the sole pathways to their resilience. Continued research in other parts of South Africa, with additional groups of youth, is needed to reach a comprehensive understanding of the socio-ecological antecedents of resilience among South African youth.
MEd, Learner support, North-West University, Vaal Triangle Campus, 2012

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Tuvendal, Magnus, and Thomas Elmqvist. "Ecosystem Services Linking Social and Ecological Systems : River Brownification and the Response of Downstream Stakeholders." Stockholms universitet, Systemekologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-80797.

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The theoretical framework of ecosystem services and that of resilience thinking are combined in an empiricalcase study of a social-ecological system. In the River Helge å catchment in southern Sweden, a slow increase in dissolved organiccarbon (DOC) results in brownification of the water with consequences on ecosystem services in the lower part of the catchmentof concern by local resource managers. An assessment of ecosystem service delivery was conducted to (1) identify plausibledrivers of brownification in the study site and assess future ecosystem service delivery for stakeholders in downstream areas.An analysis of the perspective of beneficiaries, using qualitative methods, was pursued to (2) evaluate the impacts ofbrownification on downstream stakeholders.

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Fall, Ababacar. "Le Ferlo sénégalais : approche géographique de la vulnérabilité des anthroposystèmes sahéliens." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA131028.

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L’anthroposystème pastoral du Ferlo sénégalais évolue dans un milieu historiquement négligé par les politiques agricoles en raison de ses caractéristiques biophysiques particulières, peu favorables à l’agriculture et à une forme de mise en valeur autre que l’élevage extensif, incluant une transhumance. Celui-ci permet d’exploiter des ressources très variables dans l’espace et dans le temps. Cette primauté de l’élevage itinérant est de nos jours de plus en plus contestée par le développement de l’agriculture dans un contexte marqué par l’amélioration des conditions de la pluviosité dans tout le Sahel ouest-africain, de l’épuisement des terres du Bassin aracohidier et de la multiplication des aménagements agricoles au niveau de la vallée du fleuve Sénégal. En combinant l’analyse d’images de télédétection pour la cartographie d’évolution de l’occupation du sol par le couvert végétal, l’étude de la flore et du paysage végétal et l’exploitation d’enquêtes dans les villages et les campements du Ferlo, ce mémoire de thèse tente de cerner la géographie de la vulnérabilité des populations rurales et des écosystèmes qu’elles utilisent. Ainsi les éleveurs et les pasteurs évoluent-ils avec des stratégies d’adaptation quotidienne dans ces milieux du Sénégal intérieur marqués par l’instabilité écologique profonde et par les transformations à l’oeuvre dans la société rurale sénégalaise. Ces changements socio-environnementaux considérables contribuent ainsi à la dynamique des paysages végétaux et par-delà pose la question de la dégradation des écosystèmes
The pastoral anthroposystem of Senegalese Ferlo evolves in an environment historically neglected by agricultural policies because of its characteristics particular biophysics, unfavorable to the agriculture and to the shape of development other than the extensive breeding. This primacy of the itinerant breeding is nowadays more and more disputed by the development of the farming in a context marked by the improvement of the conditions of the rainfall in West-African Sahel, soil depletion in the Groundnut Basin and the multiplication of agricultural development at the valley of the Senegal River. By combining the analysis of remote sensing imagery for mapping land cover changes by the vegetation cover, the study of flora and vegetation landscape and the exploitation of the investigations in villages and camps, this thesis attempts to define the geography of the vulnerability of rural populations and ecosystems which they use. So, pastoralists evolve with daily adaptation strategies in these circles inside Senegal marked by deep ecological instability and by the transformations at work in the Senegalese rural society. These socio-environmental changes contribute to the dynamics of plant landscapes and raise the question of ecosystem degradation

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Hofer, Nancy Dee. "An evaluation of neighbourhood sustainability assessment frameworks using ecosystem characteristics and principles of systems resilience as the evaluation criteria." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/14216.

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If human societies are to sustain over the long-term, we must manage human societies and our products, including settlements, to work within the context of a living environment. While conventional practice in neighbourhood planning has made advances in acknowledging the importance of sustainability in the built environment, it generally does not acknowledge fundamental ecological concepts such as the ecology of sites, global ecological productive carrying capacity or the dynamic nature of a living, rapidly eroding, biophysical environment. This thesis articulates the need to acknowledge the ecological context as the basis of sustainable communities. A living ecological system is not only the context in which settlements operate; ecosystems may also be a viable model from which to form settlements. This thesis proposes incorporating the model of ecosystems, the characteristics they embody and principles by which they are governed into the planning and design of settlements as a method of informing a physical form that can support sustainable communities. A case study of a local Vancouver neighbourhood, False Creek North, is used as a tangible reference point around which to frame the discussion of sustainable communities. Although not planned explicitly to be a “sustainable community” the neighbourhood embodies many of the characteristics of conventional thinking about sustainable neighbourhoods. Using sustainability assessment frameworks, the False Creek North development is evaluated for sustainability merits and weaknesses in order to understand how this model of development could be improved to better reflect concepts of sustainability. In order to ensure that the frameworks reflect a strong, ecologically bound concept of sustainability the assessment frameworks are also evaluated based on their ability to capture characteristics and principles of ecological systems using an evaluation matrix. An integrated discussion is presented on a) how well the frameworks reflect ecological principles and b) what elements of FCN display ecological sustainability characteristics. Overall, the assessment frameworks are found to be limiting in their ability to capture fundamental ecological concepts. Indicators that reflect ecological principles and characteristics are therefore proposed and examples are given as to how they might be used to measure aspects of the case study site, False Creek North.

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Manninen, O. (Outi). "The resilience of understorey vegetation and soil to increasing nitrogen and disturbances in boreal forests and the subarctic ecosystem." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526211732.

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Abstract Climate change and its warming effects on vegetation and soils are a widely recognized phenomenon. In addition to warming, the understorey vegetation in northern environments has been subjected to several environmental changes, such as increasing nitrogen (N) and other disturbances. This thesis examines the effects of N-fertilization and disturbances on the vegetation biomass and abundance, plant community composition and plant, soil and microbial N and C pools. Seedling establishment of the most common dwarf shrubs (deciduous Vaccinium myrtillus, evergreens V. vitis-idaea and Empetrum nigrum ssp. hermaphroditum) was investigated after artificial disturbance treatments (vegetation and soil removal). These studies were conducted in the boreal and subarctic ecosystems and in the forest-tundra ecotone in northern Finland. N-fertilization and disturbances enhanced the amount of graminoids in plant communities, and the recovery ability of graminoids was enhanced after N-fertilization, which homogenized the vegetation and resulted in a new stable state in the plant community. The recovery ability of evergreen dwarf shrubs was low after disturbances. Disturbances created habitats for seed germination, but the seedling establishment of dwarf shrubs studied was still limited by seed availability. N-fertilization had no effect on microbial biomass. Instead, microbial biomass decreased with disturbance treatment in the boreal forest. However, the concentration of N increased in above-ground vegetation, both after N-fertilization and disturbance without any indication of N immobilization, suggesting that plant species captured the available N effectively for their recovery. The study shows that the likely outcome of N enrichment, when combined with disturbances, is the enhanced growth of graminoids. The seedling establishment does not compensate for the reduction of the vegetative recovery of evergreen dwarf shrubs, which makes evergreen dwarf shrubs sensitive to environmental changes. As the understorey is more resilient to perturbations in the boreal forest than in the subarctic ecosystem, these results emphasize the sensitivity of the vegetation to simultaneous environmental changes in the northernmost ecosystems. Moreover, microbial properties are more resilient to environmental changes than is above-ground vegetation
Tiivistelmä Ilmaston muutos ja siitä aiheutuvan lämpenemisen vaikutus kasvillisuuteen ja maaperään on laajasti tunnustettu ilmiö. Lämpenemisen lisäksi pohjoisten alueiden aluskasvillisuuteen kohdistuu useita muutospaineita, kuten lisääntynyt typpipitoisuuden nousu ja kasvillisuutta muokkaavat häiriöt. Tässä tutkimuksessa mitattiin lisääntyneen typpipitoisuuden ja häiriöiden vaikutus kasvillisuuden biomassaan ja runsauteen sekä yhteisörakenteeseen, sekä kasvilajeihin, maaperään ja mikrobibiomassaan sitoutuneen typen ja hiilen määrään. Lisäksi tutkittiin yleisimpien varpukasvien (lehtensä pudottava mustikka, ikivihreät puolukka ja variksenmarja) siemenellistä lisääntymistä kokeellisen häiriön (kasvillisuuden tai maaperän poisto) jälkeen. Tutkimukset tehtiin boreaalisessa ja subarctisessa ekosysteemeissä sekä metsänrajaympäristössä Pohjois-Suomessa. Typpilannoitus ja häiriöt lisäsivät heinien määrää kasviyhteisöissä. Lisäksi typpilannoitus edisti heinien kasvullista palautumiskykyä häiriön jälkeen, joka johti kasvillisuuden homogenisoitumiseen ja kasviyhteisön uuteen tasapainotilaan. Häiriöt heikensivät ikivihreiden varpujen kasvullista palautumista häiriön jälkeen. Häiriö loi sopivia elinympäristöjä siementen itämiselle, mutta tutkittujen lajien siementen määrä rajoitti siemenellistä lisääntymistä. Typpilannoitus ei vaikuttanut mikrobibiomassaan, mutta häiriö vähensi mikrobibiomassaa boreaalisessa ekosysteemissä. Kuitenkin kasvien typen pitoisuudet lisääntyivät sekä lannoituksen että häiriön jälkeen ilman viitteitä typen sitoutumisesta mikrobibiomassaan. Tämä viittaa siihen, että kasvit käyttävät maaperän typen tehokkaasti häiriön jälkeiseen palautumiseen. Väitöskirjan mukaan typen lisääntyminen häiriöiden yhteydessä edistää heinien esiintymistä. Koska ikivihreiden varpujen siemenellinen lisääntyminen ei kompensoi häiriöstä kasvulliselle palautumiselle aiheutuvaa haittaa, ovat ikivihreät varvut erityisen herkkiä häiriöille. Aluskasvillisuus on vastustuskykyisempi ympäristön muutoksille boreaalisessa kuin subarktisessa ekosysteemissä, mikä korostaa pohjoisimpien alueiden herkkyyttä yhtäaikaisille ympäristön muutoksille. Maaperän olosuhteet ovat kasvillisuutta kestävämpiä ympäristön muutoksille

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47

Nowicki, Robert J. "Effects of Catastrophic Seagrass Loss and Predation Risk on the Ecological Structure and Resilience of a Model Seagrass Ecosystem." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2994.

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As climate change continues, climactic extremes are predicted to become more frequent and intense, in some cases resulting in dramatic changes to ecosystems. The effects of climate change on ecosystems will be mediated, in part, by biotic interactions in those ecosystems. However, there is still considerable uncertainty about where and how such biotic interactions will be important in the context of ecosystem disturbance and climactic extremes. Here, I review the role of consumers in seagrass ecosystems and investigate the ecological impacts of an extreme climactic event (marine heat wave) and subsequent widespread seagrass die-off in Shark Bay, Western Australia. Specifically, I compare seagrass cover, shark catch rates, and encounter rates of air breathing fauna in multiple habitat types before and after the seagrass die-off to describe post-disturbance dynamics of the seagrass community, shifts in consumer abundances, and changes in risk-sensitive habitat use patterns by a variety of mesoconsumers at risk of predation from tiger sharks (Galeocerdo cuvier). Finally, I conducted a 16 month field experiment to assess whether xi loss of top predators, and predicted shifts in dugong foraging, could destabilize remaining seagrass. I found that the previously dominant temperate seagrass Amphibolis antarctica is stable, but not increasing. Conversely, an early-successional tropical seagrass, Halodule uninervis, is expanding. Following the die-off, the densities of several consumer species (cormorants, green turtles, sea snakes, and dugongs) declined, while others (Indo-Pacific bottlenose dolphins, loggerhead sea turtles, tiger sharks) remained stable. Stable tiger shark abundances following the seagrass die-off suggest that the seascape of fear remains intact in this system. However, several consumers (dolphins, cormorants) began to use dangerous but profitable seagrass banks more often following seagrass decline, suggesting a relaxation of anti-predator behavior. Experimental results suggest that a loss of tiger sharks would result in a behaviorally mediated trophic cascade (BMTC) in degraded seagrass beds, further destabilizing them and potentially resulting in a phase shift. My work shows that climactic extremes can have strong but variable impacts on ecosystems mediated in part by species identity, and that maintenance of top predator populations may by important to ecological resilience in the face of climate change.

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isaksson, Pia. "Management, valuation and evaluation of urban greenspace and trees in relation to resilience; : The importance of ecosystem services in the built environment and how they are maintained and cared for." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231620.

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Abstract: Managing worldwide urbanization and housing shortage in cities through a resilient development isan immense issue of today. This study states the risk with urban densification, at the expense ofgreenspace, which is crucial to maintain vital ecosystem services. The nonlinear response todisturbance in ecosystems, need to be emphasized both in planning and practice, to avoiddegradation and collapse. Despite general promotion of densification as a tool to decrease negativeurban impact on surrounding landscape, as to mitigate climate change, current strategies ofcompacting cities are argued to endanger future resilience. In this work, it is stressed that valuationof greenery in urban areas should include the recognition of uncertainty, safeguarding the availabilityof all forms of ecosystem services in a changing future. Applying a framework of social-ecologicalresilience, a case-study of Stockholm regarding valuation of greenery and ecosystem services inplanning and exploitation, as in continuous management, has been carried out. A wide range ofactors within the fields of green management, planning and exploitation have been interviewed.When compared with expressed visions in comprehensive plans and policies, results from interviewsshow severe gaps between planning and practice. Foresight planning in relation to adaptivegovernance, to enhance social-ecologic interactions, is suggested a tool to improve implementationand acknowledgement of ecosystem services in urban development and design. Further, enhancedcross-learning and knowledge exchange in the social-ecological system, should be improved throughinteraction and recognition of the variety of stakeholders and multi-functional green areas tostrengthen social-ecological resilience in the urban context.
Sammanfattning: Dagens intensiva urbanisering och bostadsbrist, betonar behovet av resilient stadsutveckling. Dennastudie understryker faran med förtätning på bekostnad av grönstrukturer, vilka är avgörande förupprätthållandet av livsnödvändiga ekosystemtjänster. Ekosystems icke lineära respons påstörningar, bör uppmärksamma i både planering och praktik, för att undvika utarmning eller kollaps.Tillskillnad från ofta framhållna fördelar med förtätning, som minskad inverkan på kringliggandegrönstrukturer och motverkande av klimatförändringar, vill den här studien framhålla hurförtätningsprocesser riskerar att försämra städers resiliens. För att säkra en framtida motståndskraftoch anpassningsförmåga till förändrade omständigheter, bör värdering av grönstrukturer i stadsmiljötydliggöra framtida osäkerhetsfaktorer i relation till ekosystemens förmåga att tillhandahålla olikatjänster. Utifrån ett social-ekologiskt ramverk har en fallstudie av hur grönstrukturer värderas iplanering- och exploateringsprocesser, samt inom allmänt underhåll, genomförts i Stockholm. Enbredd av aktörer inom planering, exploatering och grönskötsel intervjuades. I jämförelse meduttryckta visioner i olika översiktsplaner och policydokument, visar resultaten från intervjuerna påflera luckor mellan planering och utförande. En långsiktig planering i samband med ett socialekologisktresilient styrelseskick, som syftar på en större förståelse och interaktion mellan socialaoch ekologiska faktorer, föreslås förbättra såväl implementering som uppmärksammande avekosystemtjänster inom stadsutformning och utveckling. Vidare kan ett utökat lärande ochkunskapsutväxling mellan och inom social-ekologiska system, öka förståelsen för- och förstärkastäders social-ekologiska resiliens.

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Hur, Ran. "Quantifying panarchy of lake systems: implication for resilience and management (Case study)." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445198.

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Liming has been used extensively in Sweden, but the management success has been only partial, mostly mitigating the impact of acidification rather than restoring the ecological communities to a self-maintaining pre-acidified state. Rather than a sound restoration tool, liming is a form of command-and-control management that comprises a significant disturbance in the system, which manifests in the form of profound alterations of biophysical settings of lakes. This thesis aims to assess biological responses to liming with a special focus on resilience by looking at the cross-scale interaction aspects of littoral invertebrate communities in limed lakes within the framework of panarchy theory. The thesis is based on multivariate time series modeling (AEM-RDA) to extract hierarchical temporal fluctuations patterns (temporal scales) in littoral invertebrate communities. This analysis tested for the premise of panarchy theory that complex systems are hierarchically structured. Time series analyses were followed by Spearman rank correlation analysis to test another premise of panarchy theory; namely, that “information” (e.g., management interventions) flows between these hierarchical scales. Specifically, Ca:Mg ratios were used as a surrogate of liming, and correlated with each temporal pattern identified by the AEM-RDA. The result showed the distinct temporal scales in littoral invertebrate communities in limed lakes, fitting the premises of panarchy theory and agreeing with previous studies that found hierarchical temporal organizations in other lake communities. The correlation analyses indicated weak cross-scale manifestation of Ca:Mg ratios in the littoral invertebrate communities, suggesting a weak information flow of liming in managed lakes. This “dilution” of management may provide one mechanism that could explain why liming is not effective in creating a self-organizing, resilient system. The results of this study allow shedding further light on liming as a coerced regime (degraded complex systems forced into a state of desired conditions (e.g., ecosystem service provisioning) through constant management). Most research has so far focused on the evaluation of traditional metrics of biodiversity, which have shown that community structure is substantially altered in limed lakes, deviating from those in circumneutral reference lakes and degraded acidified lakes. This thesis, therefore, concludes that integration of traditional ecological approaches and complexity studies may provide complementary insight into the organization of ecosystems and sustainable resource management.

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Eklöf, Johan S. "Anthropogenic Disturbances and Shifts in Tropical Seagrass Ecosystems." Doctoral thesis, Stockholm University, Department of Systems Ecology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7285.

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Seagrasses constitute the basis for diverse and productive ecosystems worldwide. In East Africa, they provide important ecosystem services (e.g. fisheries) but are potentially threatened by increasing resource use and lack of enforced management regulations. The major aim of this PhD thesis was to investigate effects of anthropogenic distur-bances, primarily seaweed farming and coastal fishery, in East African seagrass beds. Seaweed farming, often depicted as a sustainable form of aquaculture, had short- and long-term effects on seagrass growth and abundance that cascaded up through the food web to the level of fishery catches. The coastal fishery, a major subsistence activity in the region, can by removing urchin predators indirectly increase densities of the sea urchin Tripneustes gratilla, which has overgrazed seagrasses in several areas. A study using simulated grazing showed that high magnitude leaf removal – typical of grazing urchins – affected seagrasses more than low magnitude removal, typical of fish grazing. Different responses in two co-occurring seagrass species furthermore indicate that high seagrass diversity in tropical seagrass beds could buffer overgrazing effects in the long run. Finally, a literature synthesis suggests that anthropogenic disturbances could drive shifts in seagrass ecosystems to an array of alternative regimes dominated by other or-ganisms (macroalgae, bivalves, burrowing shrimp, polychaetes, etc.). The formation of novel feedback mechanisms makes these regimes resilient to disturbances like seagrass recovery and transplantation projects. Overall, this suggests that resource use activities linked to seagrasses can have large-scale implications if the scale exceeds critical levels. This emphasizes the need for holistic and adaptive management at the seascape level, specifically involving improved techniques for seaweed farming and fisheries, protection of keystone species, and ecosystem-based management approaches.

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Dissertations / Theses on the topic 'Ecosystem resiliency'

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