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Proposta de padronização em avaliação de impactos ambientaisSandoval, Maitê de Souza [UNESP] 18 July 2008 (has links) (PDF)
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sandoval_ms_me_rcla.pdf: 689985 bytes, checksum: f333029b423c9df4992d4070398b119c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A avaliação da significância dos impactos ambientais continua a ser um importante componente crítico ainda mal compreendido da prática da avaliação de impactos ambientais. Este trabalho é um estudo sobre as conclusões de uma revisão bibliográfica sobre a avaliação e comunicação de avaliação do impacto ambiental praticada no Brasil. É dada especial atenção para a importância da utilização de critérios, padrões e métodos de avaliação de impactos ambientais que pretendendo incorporar mais eficiência nos estudos de impacto ambiental. Assim, o objetivo desta pesquisa foi a realização de uma proposta, incluindo o desenvolvimento de procedimentos e aplicar na avaliação de impactos ambientais situações relativas à sua formulação, aplicação e interpretação da significância dos critérios, conclusões e recomendações pertinentes para respeitar o objetivo da avaliação de impacto ambiental que é garantir a viabilidade ambiental das atividades humanas. / The evaluation of the significance of environmental impacts remains an important critical yet poorly understood component of environmental impact assessment practice. This work is a study upon the findings of a bibliographic review about the evaluation and communication of environmental impact assessment in Brazil practice. Particular attention is given to the use of significance criteria, thresholds and EIA methodologies intending to incorporate more efficiency of environmental impact statement. Thus, the aim of this research was the accomplishment of a proposal including the development of procedures to apply in EIA issues surrounding the formulation, application and interpretation of significance criteria, conclusions and recommendations relevant to respect the aim of EIA that in provide environmental viability of men activities.
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Social Impact Assessment :analyse d'un outil d'aide à la décision pour la lutte contre la pauvreté et les inégalités sociales de santé: Etude des conditions nécessaires à la fonction d'apprentissage conceptuel de l'outil dans le contexte bruxelloisFeyaerts, Gille 27 April 2018 (has links)
Malgré leur potentiel important et leur introduction de plus en plus fréquente à différents niveaux politiques, le rôle des outils d’évaluation d’impact dans le processus politique reste questionné. Leur efficacité semble particulièrement limitée dans le cadre des problématiques comme la pauvreté et les inégalités sociales. Au-delà de leur complexité, c’est surtout le caractère controversé de ces phénomènes et le fait qu’il n’existe pas de consensus sur la manière d’aborder la pauvreté et les inégalités sociales, qui posent problème. Dans ce contexte, les connaissances issues d’une évaluation d’impact ne vont pas toujours jouer un rôle direct et instrumental dans la prise de décisions politiques.Dans cette thèse de doctorat, nous avons analysé comment adapter et améliorer le design et la mise en œuvre de l’outil de ‘Social Impact Assessment’ (ou de ‘Test d’impact pauvreté’), afin de mieux exploiter son potentiel d’aide à la décision en matière de lutte contre la pauvreté. Sur base d’une analyse (théorique et pratique) du fonctionnement des processus politique et décisionnels et des mécanismes de policy change, nous nous sommes intéressés aux différentes fonctions d’aide à la décision qu’il peut jouer. Nous avons identifié la fonction d’apprentissage instrumental comme la fonction la plus ‘consensuelle’ et attendue de la part des décideurs politiques, et la fonction d’apprentissage conceptuel comme la fonction potentiellement la plus puissante, mais souvent négligée et donc sous-exploitée.Via la fonction d’apprentissage instrumental, le test d’impact pauvreté doit apporter des informations précises et directement utiles à la décision. Dans cette perspective, l’accent est mis sur l’amélioration et l’optimalisation de la proposition politique, tout en respectant son cadre de référence, et en se concentrant sur ses aspects opérationnels. L’identification d’effets potentiels négatifs peut alors donner lieu à la formulation de propositions d’adaptation permettant d’atténuer voire compenser ces effets, tandis qu’un impact potentiel positif peut être davantage accentué et maximisé.Via la fonction d’apprentissage conceptuel, le test d’impact pauvreté devrait permettre d’introduire de nouvelles idées, perspectives et hypothèses qui contribuent à une compréhension plus élargie de la pauvreté, permettant ainsi de mieux appréhender les effets potentiels d’une politique sur la pauvreté. Dans cette perspective, le test d’impact pauvreté devrait contribuer, à plus long terme, à ce que les politiques publiques, quel que soit leur « secteur », puissent contribuer à une action politique globale efficace, pertinente et durable pour réduire (ou lutter contre) la pauvreté.Notre proposition de design pour le test d’impact pauvreté est guidée par le souci d’exploitation de ce double potentiel. Nous avons suivi une démarche itérative, dans laquelle nous avons développé une première proposition de design sur base (1) d’une revue de la littérature et (2) d’une analyse d’expériences en cours en matière d’évaluation d’impact sur la santé et la pauvreté en Irlande et au Québec (Canada). Cette proposition a été testée et appliquée concrètement dans des contextes de ‘real-world policy-making’. Nous avons effectué deux études de cas dans le contexte bruxellois :la première sur le projet d’ordonnance concernant le parcours d’accueil et d’intégration des primo-arrivants, la deuxième sur le projet d’assurance autonomie. Les observations faites sur le terrain, qui ont été confrontées avec des éléments issus de la littérature scientifique, ont permis d’adapter et affiner notre proposition.La proposition de design pour le test d’impact pauvreté est composée de quatre axes :(1) L’articulation du test d’impact pauvreté au timing et contraintes du processus politique et décisionnel ;(2) la clarification de ce que nous entendons par la ‘pauvreté’ et ‘l’impact sur la pauvreté’ et un schéma d’analyse des déterminants de la pauvreté, permettant d’identifier de quelle manière et à quel niveau une politique impacte la pauvreté ;(3) la proposition d’une démarche méthodologique d’évaluation, inspirée de l’approche de l’évaluation réaliste. Pour cet axe, nous avons défini une série de questions pour un test d’impact pauvreté ;(4) l’intégration des connaissances et de l’expertise des personnes en situation de pauvreté dans le test d’impact pauvreté. / Doctorat en Sciences de la santé Publique / info:eu-repo/semantics/nonPublished
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The environmental, social and economic impacts of an artificial surf reef : the UK experienceRendle, Emma Jane January 2016 (has links)
The study presented in this thesis discusses the topic of ASRs through the use of a specific case study constructed at Boscombe, UK. With the main aim to provide an impartial and independent study into the environmental, social and economic impacts of an ASR. The research presented is therefore multidisciplinary in nature, the separate components utilise key techniques from the geophysical, numerical modelling and socio-economic disciplines are combined to present a significant contribution to the knowledge and understanding of ASRs. Whilst previous studies have focused on one of these disciplines, there are no independent detailed studies of a constructed ASR utilising an multidisciplinary approach. The ASR concept and structures are still in their development infancy, the subject has received cursory independent review in the literature. There have been few successful projects, those that have survived structurally in the ocean are not being used primarily for surfing. The Boscombe ASR is an example of high overspend, poor management and construction, loss of geotextile SFC and users deem the project a failure. The consequences of not correctly planning, managing and overseeing the construction has resulted in a poorly viewed project of limited success. All stages of this project could have benefited from thoughtful planning, thereby avoiding this outcome. If lessons are to be learnt from this project then the planning and management are key areas of the process that need addressing. Ensuring that any future ASR projects are securely integrated with the coastal zone management plan will provide sustainability and success. The DPSIR framework approach can be used to highlight and address the causes of problems in the project. This framework enables the various disciplines to be discussed in relation to each other; links can be identified between the environmental, social and economic impacts of the ASR construction. Strict protocols will increase the success of any ASR project. The final crest height of the Boscombe ASR was 0.5 m higher than the final design height, this is a fundamental design flaw that should not be occurring in modern coastal engineering practice. It is suggested that guidelines are written based on this research for the design and construction process of an ASR. The recommendations and guidelines for ASR monitoring are provided by this research. The emphasis for future projects should lie in the final design and in monitoring, baseline field data should be collected to understand the environmental state change and socio-economic impacts. Planning and government proposals should be accompanied by extensive stakeholder engagement ensuring transparency for the project and ownership within the coastal community. The exclusion of stakeholders at key decision points created distrust and misunderstanding towards the Boscombe ASR project. Avoiding unrealistic expectations within the surfing community and wider coastal community was discussed throughout this research, and by others in the literature. This research agrees with these statements, the issue of poor surfability would be improved by a greater area to manipulate the bathymetry. However this would come at a greatly increased cost in geotextile SFCs, which the current construction method is certainly not capable of delivering successfully. It would be recommended in this case that an alternative construction material was used that is resilient to the marine environment and readily adaptable given poor performance. Further testing of materials, both geotextile SFCs and alternatives, are required for the successful advancement of ASR technology.
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Identifying New Invasives In The Face Of Climate Change: A Focus On Sleeper PopulationsO'Uhuru, Ayodelé C. 28 October 2022 (has links)
Sleeper populations are established populations of a non-native species whose population growth is limited by one or more abiotic or biotic conditions, such as climate change. While the northeastern US is predicted to be a hotspot for future invasions, identifying potential sleeper populations before they become invasive can inform proactive, climate-smart invasive species management. I focused on 169 introduced species that are established in one or more northeastern states. I used the Environmental Impact Classification for Alien Taxa (EICAT) framework to systematically identify and review the peer-reviewed literature for these candidate species to quantify their negative ecological and socioeconomic impacts. I identified 49 plants with ‘major’ impacts linked to the decline of multiple native species or loss of community diversity. Using high negative ecological impact, habitat suitability, and climate suitability as selection criteria, I highlight 37 species as high priority for management in the North Atlantic –Appalachian Region.
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A critical assessment of EIA follow-up conditions formulated for Environmental Authorisations in Mpumalanga Province / Ntsanko Millicent NdlovuNdlovu, Ntsanko Millicent January 2015 (has links)
Compliance monitoring is a continuous process used to ensure that conditions
stipulated in an environmental authorisation are adhered to. Compliance monitoring is a
key component of Environmental Impact Assessment (EIA) and EIA follow-up. The aim
of this research was to critically assess EIA follow-up conditions formulated for
Environmental Authorisations in Mpumalanga Province. The practicability of conditions
set out in the authorisation for EIA follow-up are of particular concern. Forty-two (42)
environmental authorisations (EAs) issued under the 2010 NEMA EIA regulations were
reviewed and assessed to analyse information relating to follow-up practice.
In order to synthesise the data effectively and create a comprehensive analysis, the
EAs were divided into project type categories rather than listed activity categories. The
assessment results on the strengths and weaknesses related to compliance monitoring
and enforcement of the authorisation conditions revealed that the EIA follow-up
conditions in Mpumalanga do make provision of EIA follow-up. The EAs fulfils the
requirements of regulation 37 of the NEMA EIA regulations 2010 by promoting
compliance monitoring of impacts. However, some conditions raises difficulty in
monitoring due to their impracticability. Another weakness is that conditions focus
mainly on the construction phase and very little attention is paid to operational and
decommissioning impacts. The analyses results show that the practicability of the
authorised conditions for environmental compliance monitoring had the following
challenges: conditions intended to mitigate the adverse environmental impacts are
generic and do not apply to specific projects or activities being authorised and there are
no clearly defined timeframes for conditions requiring repetitive monitoring. Moreover,
the study revealed gaps in monitoring of the authorised conditions that included poor
clarity of roles of environmental control officers (ECOs) and auditors and a lack of
reference to sections to be complied with pertaining to other relevant legislation.
The critical assessment of the EIA follow-up conditions formulated for Environmental
Authorisations in Mpumalanga Province indicate that the formulation of conditions have
implications in ensuring that compliance is effectively implemented. Clearly defined
conditions will ensure proper interpretation and correct implementation for compliance
purposes. / M (Environmental Management), North-West University, Potchefstroom Campus, 2015
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Understanding independent environment control officers : learning from major South African construction projects / Johannes Albertus WesselsWessels, Johannes Albertus January 2015 (has links)
An independent industry of Environmental Control Officers (ECOs) is active on various
construction sites across South Africa. It forms part of a global network of verifiers, such
as Environmental Impact Assessment (EIA) and EIA follow-up verifiers. This network
authenticates statements about and the implementation of sustainability commitments
made during the planning phase of major construction projects. International studies
show that the construction industry is experiencing many challenges to deliver
sustainability commitments, including inadequate collaboration between role players, illdefined
roles and responsibilities, and insufficient use of environmental governance
approaches. On-site verifiers like ECOs may aid in restraining these challenges by
bridging ineffective governance approaches, such as classic EIA with new governance
approaches, for instance self-responsibility (e.g. Environmental Management Systems
(EMSs)) and involvement of third parties. Moreover, an “independent from all”
verification function may be vital in developing countries such as South Africa, where
trust between the government, market and public is particularly fragile due to historical
injustices. Interestingly, limited learning has been drawn and shared from this function’s
real-world experience. There are also differing views on the role, independence and
value of ECOs, due to roles, frequent interaction with persons responsible for delivering
sustainability commitments, and collaboration with third parties being ill-defined. The
overarching purpose of this study is to advance understanding of independent ECOs in
major South African construction projects. Three lines of inquiry are followed. The first is
to define what the role is, or ideally should be, of an ECO in the South African
compliance monitoring and enforcement effort. The second is to identify what factors
might influence the independence of verifiers. The third is to appraise how and to what
extent independent EIA follow-up verifiers add value in major construction projects in
the developing country context of South Africa.
This study’s research assumptions are based on the real world of ECOs and uses a
mixed method research approach to draw knowledge from the industry. The strategies
of inquiry include a survey, interviews, and multiple case study evaluations. The
methods for data collection include literature review, a self-administered survey
questionnaire, semi-structured interviews, video material, observations of practice at
case studies, and the collection of project documentation. The methods used for data
analysis are the categorisation and measuring of opinions and statements of survey
participants, the analysis of video material and project documentation, and the nominal
categorisation and ordinal scaling of case study results. Three journal articles capture
the essence of the research results and form part of the thesis report, as prescribed by
the North-West University’s rules for doctoral theses in article format. All three articles
were peer-reviewed and published in journals aimed at international audiences. Article
1 of the thesis highlights that an industry of ECOs fulfils numerous roles at various
construction sites across South Africa. The results identify the importance of ECOs
functioning independently of all role-players, but warn that obsessing about
independence may compromise the ability of ECOs to fulfil their roles. The results also
show that industry is in need of competence and the regulation thereof, as well as
support from all role players. By drawing from the research results, the thesis defines an
ECO.
Article 2 of the thesis reiterates that independence is central to internationally acclaimed
verification fields and important to ensure the credibility of EIA. The study identifies 18
factors that might influence the independence of EIA follow-up verifiers and divides the
factors into five categories: financial, commercial, professional, personal, and other. By
identifying and sharing these factors, this thesis aids in anticipating and avoiding
potential conflict of interest between environmental role players. Article 3 strengthens
the continuum between environmental governance approaches by conceptualising a
framework for appraising the value of independent EIA follow-up verifiers. The
framework provides for inter-linking principles and objectives of sustainability to the
performance areas of EIA, EIA follow-up and the EMS. The appraisal results indicate
that independent verifiers add most value when they are involved in screening, checking
compliance, influencing decisions, community engagement, and integrating
environmental governance approaches. The study confirms the benefits of adaptable,
proactive, experienced, and independent EIA follow-up verifiers, such as ECOs, on
major South African construction projects. / PhD (Geography and Environmental Management), North-West University, Potchefstroom Campus, 2015
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A critical assessment of EIA follow-up conditions formulated for Environmental Authorisations in Mpumalanga Province / Ntsanko Millicent NdlovuNdlovu, Ntsanko Millicent January 2015 (has links)
Compliance monitoring is a continuous process used to ensure that conditions
stipulated in an environmental authorisation are adhered to. Compliance monitoring is a
key component of Environmental Impact Assessment (EIA) and EIA follow-up. The aim
of this research was to critically assess EIA follow-up conditions formulated for
Environmental Authorisations in Mpumalanga Province. The practicability of conditions
set out in the authorisation for EIA follow-up are of particular concern. Forty-two (42)
environmental authorisations (EAs) issued under the 2010 NEMA EIA regulations were
reviewed and assessed to analyse information relating to follow-up practice.
In order to synthesise the data effectively and create a comprehensive analysis, the
EAs were divided into project type categories rather than listed activity categories. The
assessment results on the strengths and weaknesses related to compliance monitoring
and enforcement of the authorisation conditions revealed that the EIA follow-up
conditions in Mpumalanga do make provision of EIA follow-up. The EAs fulfils the
requirements of regulation 37 of the NEMA EIA regulations 2010 by promoting
compliance monitoring of impacts. However, some conditions raises difficulty in
monitoring due to their impracticability. Another weakness is that conditions focus
mainly on the construction phase and very little attention is paid to operational and
decommissioning impacts. The analyses results show that the practicability of the
authorised conditions for environmental compliance monitoring had the following
challenges: conditions intended to mitigate the adverse environmental impacts are
generic and do not apply to specific projects or activities being authorised and there are
no clearly defined timeframes for conditions requiring repetitive monitoring. Moreover,
the study revealed gaps in monitoring of the authorised conditions that included poor
clarity of roles of environmental control officers (ECOs) and auditors and a lack of
reference to sections to be complied with pertaining to other relevant legislation.
The critical assessment of the EIA follow-up conditions formulated for Environmental
Authorisations in Mpumalanga Province indicate that the formulation of conditions have
implications in ensuring that compliance is effectively implemented. Clearly defined
conditions will ensure proper interpretation and correct implementation for compliance
purposes. / M (Environmental Management), North-West University, Potchefstroom Campus, 2015
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Understanding independent environment control officers : learning from major South African construction projects / Johannes Albertus WesselsWessels, Johannes Albertus January 2015 (has links)
An independent industry of Environmental Control Officers (ECOs) is active on various
construction sites across South Africa. It forms part of a global network of verifiers, such
as Environmental Impact Assessment (EIA) and EIA follow-up verifiers. This network
authenticates statements about and the implementation of sustainability commitments
made during the planning phase of major construction projects. International studies
show that the construction industry is experiencing many challenges to deliver
sustainability commitments, including inadequate collaboration between role players, illdefined
roles and responsibilities, and insufficient use of environmental governance
approaches. On-site verifiers like ECOs may aid in restraining these challenges by
bridging ineffective governance approaches, such as classic EIA with new governance
approaches, for instance self-responsibility (e.g. Environmental Management Systems
(EMSs)) and involvement of third parties. Moreover, an “independent from all”
verification function may be vital in developing countries such as South Africa, where
trust between the government, market and public is particularly fragile due to historical
injustices. Interestingly, limited learning has been drawn and shared from this function’s
real-world experience. There are also differing views on the role, independence and
value of ECOs, due to roles, frequent interaction with persons responsible for delivering
sustainability commitments, and collaboration with third parties being ill-defined. The
overarching purpose of this study is to advance understanding of independent ECOs in
major South African construction projects. Three lines of inquiry are followed. The first is
to define what the role is, or ideally should be, of an ECO in the South African
compliance monitoring and enforcement effort. The second is to identify what factors
might influence the independence of verifiers. The third is to appraise how and to what
extent independent EIA follow-up verifiers add value in major construction projects in
the developing country context of South Africa.
This study’s research assumptions are based on the real world of ECOs and uses a
mixed method research approach to draw knowledge from the industry. The strategies
of inquiry include a survey, interviews, and multiple case study evaluations. The
methods for data collection include literature review, a self-administered survey
questionnaire, semi-structured interviews, video material, observations of practice at
case studies, and the collection of project documentation. The methods used for data
analysis are the categorisation and measuring of opinions and statements of survey
participants, the analysis of video material and project documentation, and the nominal
categorisation and ordinal scaling of case study results. Three journal articles capture
the essence of the research results and form part of the thesis report, as prescribed by
the North-West University’s rules for doctoral theses in article format. All three articles
were peer-reviewed and published in journals aimed at international audiences. Article
1 of the thesis highlights that an industry of ECOs fulfils numerous roles at various
construction sites across South Africa. The results identify the importance of ECOs
functioning independently of all role-players, but warn that obsessing about
independence may compromise the ability of ECOs to fulfil their roles. The results also
show that industry is in need of competence and the regulation thereof, as well as
support from all role players. By drawing from the research results, the thesis defines an
ECO.
Article 2 of the thesis reiterates that independence is central to internationally acclaimed
verification fields and important to ensure the credibility of EIA. The study identifies 18
factors that might influence the independence of EIA follow-up verifiers and divides the
factors into five categories: financial, commercial, professional, personal, and other. By
identifying and sharing these factors, this thesis aids in anticipating and avoiding
potential conflict of interest between environmental role players. Article 3 strengthens
the continuum between environmental governance approaches by conceptualising a
framework for appraising the value of independent EIA follow-up verifiers. The
framework provides for inter-linking principles and objectives of sustainability to the
performance areas of EIA, EIA follow-up and the EMS. The appraisal results indicate
that independent verifiers add most value when they are involved in screening, checking
compliance, influencing decisions, community engagement, and integrating
environmental governance approaches. The study confirms the benefits of adaptable,
proactive, experienced, and independent EIA follow-up verifiers, such as ECOs, on
major South African construction projects. / PhD (Geography and Environmental Management), North-West University, Potchefstroom Campus, 2015
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Advancing Methods to Measure the Atmospheric CO2 Sink from Carbonate Rock WeatheringSalley, Devon, Mr. 01 April 2016 (has links)
With rising atmospheric CO2 concentrations, a detailed understanding of processes that impact atmospheric CO2 fluxes is required. While a sink of atmospheric carbon from the continents to the ocean from carbonate mineral weathering is, to some degree, offset by carbonate mineral precipitation in the oceans, efforts are underway to make direct measurements of these fluxes. Measurement of the continental sink has two parts: 1) measurement of the dissolved inorganic carbon (DIC) flux leaving a river basin, and 2) partitioning the inorganic carbon flux between the amount removed from the atmosphere and the portion from the bedrock. This study attempted to improve methods to measure the DIC flux using existing data to estimate the DIC flux from carbonate weathering within the limestone karst region of south central Kentucky. The DIC flux from the Barren River drainage basin upstream from Bowling Green in southern Kentucky and northern Tennessee, and the upper Green River drainage basin, upstream from Greensburg, Kentucky, was measured, each for a year, using U.S.G.S. discharge data and water-chemistry data from municipal water plants. A value of the (DIC) flux, normalized by time and area of carbonate rock, of 4.29 g km-3 day-1 was obtained for the Barren River, and 4.95 kg km-3 for the Green. These compared favorably with data obtained by Osterhoudt (2014) from two nested basins in the upper Green River with values of 5.66 kg km-3 day-1 and 5.82 kg km-3 day-1 upstream from Greensburg and Munfordville, respectively. Additional normalization of the values obtained in this study
by average precipitation minus evapotranspiration over the area of carbonate rock, or water available for carbonate dissolution, resulted in values of 5.61x107 g C (km3 H20)- 1 day-1 (grams of carbon per cubic kilometer of water, per day) for the Barren, and 7.43x107g C (km3 H20)-1 day-1 for the Green River. Furthermore, a statistical relationship between the total DIC flux and time-volume of water available for dissolution has been observed, yielding an r2 value of 0.9478. This relationship indicates that the primary variables affecting DIC flux for these drainage basins are time and the volume of water available for dissolution.
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Impacts of Hydrological Alterations in the Mekong Basin to the Tonle Sap EcosystemArias, Mauricio Eduardo January 2013 (has links)
The Tonle Sap is the largest and most important natural wetland in Southeast Asia. It covers an area of more than 15,000 km2 with a unique mosaic of natural and agricultural floodplain habitats that coexist with the largest fishery in the Mekong Basin. Accelerating hydropower development and climate change, however, are altering the Mekong’s hydrology, which could negatively affect downstream ecosystems.
The Tonle Sap is facing a two-fold problem. First, the link between its hydrology and ecosystem properties is not well understood. Second, potential ecological changes caused by future hydrological disruptions related to hydropower and climate change are unknown. Thus, the main objective of this thesis was to quantify how alterations to the Mekong hydrology could affect the Tonle Sap ecosystem. The following studies were performed to addressed the objective: (1) an assessment of landscape patterns using geographical information and remote sensing tools; (2) an assessment of habitat patterns based on field surveys of water, vegetation, and soils; (3) ecosystem function modelling to simulate net primary production (NPP) as a function of water quantity, sediments, and habitat type; and (4) fauna habitat modelling linking the results from the assessment of landscape patterns to fauna species.
The assessment of landscape patterns revealed a distinct relationship between inundation and vegetation. Habitats in the Tonle Sap were divided into five groups based on annual flood duration, as well as physiognomic factors and human activity: (1) open water, (2) gallery forest, (3) seasonally flooded habitats, (4) transitional habitats, and (5) rainfed habitats. Large habitat shifts could occur as a result of hydropower development scenarios by the 2030s; areas optimal for gallery forest could decrease by 82% from baseline conditions, whereas areas of rainfed habitats could increase by 10-13 % (813-1061 km2).
The assessment of habitat patterns demonstrated that despite the complexity and intense human use of this ecosystem, the flood-pulse is the underlying driver of habitat characteristics by (1) determining inundation depth and duration; (2) creating the main soils gradient; (3) limiting the area cleared for agriculture; (4) influencing vegetation structure and water quality; and (5) shaping the composition of plant species.
The ecosystem function model was used to estimate a reduction of 9-39% in annual NPP caused by different scenarios of hydropower development and/or climate change during 2032-2042. Cumulative impacts from hydropower would disrupt NPP to a greater extent than climate change.
The fauna habitat model revealed that species richness was greatest in the gallery forests and seasonally flooded habitats. Animals that permanently reside in or that rely on these habitats to complete essential life-history stages would be the most affected by future changes.
This thesis provides the first quantitative formulation that directly links fundamental components of the Tonle Sap ecosystem to its flood-pulse hydrology. It also provides a comprehensive assessment of the impacts of expected hydrological alterations. Hydropower is expected to bring more abrupt and distinct ecological alterations than climate change in future decades. Relative aerial changes to the gallery forests are expected to be greater than in other habitats. A decline of the Tonle Sap’s ecosystem services will occur if appropriate measures are not implemented. These measures include mitigating hydropower alterations, conserving natural habitats in areas that are likely to remain hydrologically undisturbed, restoring natural habitats in projected areas for optimal growth, and optimizing agricultural practices in the floodplain. Research findings from this thesis focused on the Tonle Sap, but given the fundamental commonalities between this system and other large floodplains, the information presented is highly informative to other large flood-pulse driven systems around the globe.
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