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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Towards an operational measurement of socio-ecological performance

Kettner, Claudia, Köppl, Angela, Stagl, Sigrid 02 1900 (has links) (PDF)
Questioning GDP as dominant indicator for economic performance has become commonplace. For economists economic policy always aims for a broader array of goals (like income, employment, price stability, trade balance) alongside income, with income being the priority objective. The Stiglitz-Sen-Fitoussi Commission argued for extending and adapting key variables of macroeconomic analysis. International organisations such as the EC, OECD, Eurostat and UN have proposed extended arrays of macroeconomic indicators (see 'Beyond GDP', 'Compendium of wellbeing indicators', 'GDP and Beyond', 'Green Economy', 'Green Growth', 'Measuring Progress of Societies'). Despite these high profile efforts, few wellbeing and environmental variables are in use in macroeconomic models. The reasons for the low uptake of socio-ecological indicators in macroeconomic models range from path dependencies in modelling, technical limitations, indicator lists being long and unworkable, choices of indicators appearing ad hoc and poor data availability. In this paper we review key approaches and identify a limited list of candidate variables and - as much as possible - offer data sources. / Series: WWWforEurope
22

The ecological effects of the cleared boundaries of Bruce Peninsula National Park

St. James, Katherine 06 November 2009 (has links)
Bruce Peninsula National Park (BPNP) clears a 2 m swath of trees on the boundary in order to make it clear when one is entering the park from any neighbouring land; this in particular aims to protect the park and its inhabitants from illegal actions such as hunting and logging. This study looks at the ecological effects of this practice by measuring various microclimate variables and the abundance of eastern redback salamanders (Plethodon cinereus) on the boundary and comparing these measurements to parallel transects at 5, 10, 15, 20, and 40 m. Because it is a small linear development, it is then compared to other types of linear developments, such as roads, trails, and pipelines. The microclimate variables of air temperature, slug abundance, canopy cover, soil pH, total cover area, litter depth, and relative humidity were all significantly affected (p<0.05) up to 10 m into the adjacent forest, indicating that the cleared boundaries do change the surrounding microclimate. Soil pH, downed woody cover area, litter depth, and canopy cover were significantly affected (p<0.05) up to 5 m away from the boundary. Sixty hectares, or 0.4%, of the land area of BPNP is thus affected by the microclimate changes caused by the cleared boundary. These effects are similar to those found for other narrow, vegetated linear developments such as trails. Over double the number of salamanders were found on the boundary as compared to in the forest; this is due to higher cover area availability on the cleared boundary from the felled trees. Therefore, the boundary does not act as a barrier to eastern redback salamander movement, nor does it fragment the local population. Salamander abundance was best explained by the amount of cover area, snail abundance, and the dominant type of vegetation present along transects. It was also found in an additional study that salamander abundance tended to increase with increasing days since the last precipitation event, contrary to most woodland salamander monitoring protocols and methods. The boundaries were seen also to be used by hunters and recreationalists through incidental observations of human disturbance. This increased access to remote areas of the park through use of the cleared boundaries is an issue that requires further study, as the boundary itself may be leading to an increase in illegal activity. Recommendations to BPNP include leaving downed woody cover on the boundary, minimizing the boundary width, reducing lines of sight, decreasing accessibility, increasing landowner and park staff education, communicating with adjacent landowners, and securing funding to complete and maintain the boundary clearing.
23

The ecological effects of the cleared boundaries of Bruce Peninsula National Park

St. James, Katherine 06 November 2009 (has links)
Bruce Peninsula National Park (BPNP) clears a 2 m swath of trees on the boundary in order to make it clear when one is entering the park from any neighbouring land; this in particular aims to protect the park and its inhabitants from illegal actions such as hunting and logging. This study looks at the ecological effects of this practice by measuring various microclimate variables and the abundance of eastern redback salamanders (Plethodon cinereus) on the boundary and comparing these measurements to parallel transects at 5, 10, 15, 20, and 40 m. Because it is a small linear development, it is then compared to other types of linear developments, such as roads, trails, and pipelines. The microclimate variables of air temperature, slug abundance, canopy cover, soil pH, total cover area, litter depth, and relative humidity were all significantly affected (p<0.05) up to 10 m into the adjacent forest, indicating that the cleared boundaries do change the surrounding microclimate. Soil pH, downed woody cover area, litter depth, and canopy cover were significantly affected (p<0.05) up to 5 m away from the boundary. Sixty hectares, or 0.4%, of the land area of BPNP is thus affected by the microclimate changes caused by the cleared boundary. These effects are similar to those found for other narrow, vegetated linear developments such as trails. Over double the number of salamanders were found on the boundary as compared to in the forest; this is due to higher cover area availability on the cleared boundary from the felled trees. Therefore, the boundary does not act as a barrier to eastern redback salamander movement, nor does it fragment the local population. Salamander abundance was best explained by the amount of cover area, snail abundance, and the dominant type of vegetation present along transects. It was also found in an additional study that salamander abundance tended to increase with increasing days since the last precipitation event, contrary to most woodland salamander monitoring protocols and methods. The boundaries were seen also to be used by hunters and recreationalists through incidental observations of human disturbance. This increased access to remote areas of the park through use of the cleared boundaries is an issue that requires further study, as the boundary itself may be leading to an increase in illegal activity. Recommendations to BPNP include leaving downed woody cover on the boundary, minimizing the boundary width, reducing lines of sight, decreasing accessibility, increasing landowner and park staff education, communicating with adjacent landowners, and securing funding to complete and maintain the boundary clearing.
24

Ecological water quality indices in environmental management

Leung, Wai-shun, Wilson., 梁威信. January 2006 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
25

Platanthera blephariglottis : une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec

Laroche, Vincent 12 1900 (has links)
Ce mémoire visait à déterminer si la platanthère à gorge frangée (Platanthera blephariglottis var. blephariglottis), une orchidée, est une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes. Les indicateurs d’intégrité écologique sont des outils indispensables pour évaluer efficacement les composantes d’un écosystème. Les résultats indiquent que l’abondance de la platanthère est fortement liée à l’indice de qualité floristique (FQAI). Le FQAI est aussi un excellent prédicateur de la présence de l’espèce, avec un taux de succès à 87%. D’autre part, l’abondance de l’orchidée est négativement affectée par les activités anthropiques et la matrice environnante. D’un point de vue descriptif, les habitats renfermant une grande abondance d’orchidées sont caractérisés par une faible microtopographie de surface et un recouvrement important de bryophytes et d’éricacées de petite taille. Globalement, ce mémoire a montré que la platanthère renferme un potentiel pour être indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec. / The aim of this study was to evaluate whether White Fringed Orchid (Platanthera blephariglottis var. blephariglottis) can be used as an indicator of Sphagnum bog integrity. Ecological indicators of integrity are important tools as it is impossible to monitor efficiently all components of an ecosystem. Results indicate that White Fringed Orchid abundance is highly linked with floristic quality assessment index (FQAI). FQAI is also a good predictor of presence of the species, with an accuracy of 87%. On the other hand, orchid abundance is negatively affected by anthropogenic activities and the environmental matrix. Similarly, peatlands having low edge effect are characterized by higher orchid abundance than those more influenced by edges. From a descriptive perspective, high orchid abundance habitat is characterized by low surface microtopography, high bryophyte and small ericaceous covers. Globally, this study has shown that White Fringed Orchid has potential to evaluate ecological integrity in Sphagnum bogs in Québec.
26

Evaluation des services écosystémiques par la méthode des matrices de capacité : analyse méthodologique et applications à l'échelle régionale / Ecosystem services assessment based on the capacity matrix : methodological analysis and regional-scale applications

Campagne, Carole Sylvie 05 November 2018 (has links)
Les services écosystémiques (SE) sont définis comme les bénéfices que les humains retirent des écosystèmes. A titre illustratif, un arbre peut produire des fruits, séquestre du carbone et différentes activités récréatives ou valeurs esthétiques lui sont liées. Parmi les différentes approches d’évaluation des SE, la matrice de capacité est une méthode considérée comme flexible et rapide à mettre en œuvre. Constituée d’une table d’allocation d’un score pour chaque SE et chaque écosystème considéré, elle est de plus en plus utilisée en France, ainsi qu’à l’international. Dans le cadre de cette thèse nous avons travaillés sur l’évaluation des scores à dire d’experts dans le but, notamment, de déterminer certains biais et limites méthodologiques, mais également d’explorer des développements innovants pour différentes applications sur le Parc Naturel Région Scarpe-Escaut et la Région Hauts-de-France. Enfin nous avons intégré les disservices (les effets indésirables de la nature sur l’Homme) et l’intégrité écologique (la condition/santé de l’écosystème) dans l’évaluation des SE afin d’avoir une vision plus complète de la relation homme-nature / Ecosystem services (ES) are the benefits that humans derive from ecosystems. For example, a tree produces fruit that we pick, sequesters carbon as it grows, supports various recreational activities and has aesthetic value. Among the different approaches developed to assess ES, the experts-based capacity matrix is flexible and quick to implement. The matrix is a look-up table that assigns each ecosystem type a score defined by experts expressing its ES capacity. It is increasingly used in France, Europe and internationally. Three themes are addressed in the thesis: (i) methodological analysis to define and specify limits and specify methodology to address them, (ii) application of the method to the Scarpe-Escaut Regional Natural Park and to the Hauts-de-France Region, and (iii) integration of the evaluation of disservices (undesired effects of the natural environment on humans) and ecological integrity (condition/health of the ecosystem) into the evaluation of ES to take fuller account of the relation between humans and their natural environment.
27

An ecological integrity assessment of the lower Amatikulu, Thukela and Umvoti rivers, KwaZulu-Natal, South Africa / Johannes Jacobus Venter

Venter, Johannes Jacobus January 2013 (has links)
The ecosystem services of the lower Amatikulu, Thukela and Umvoti Rivers are used extensively through sugarcane agricultural activities, heavy industries and rural sewage-treatment works. These activities affect the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. The Umvoti River is already being referred to as a „working river‟. This study aims to determine the current state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers and to establish trends between current and historical periods for the evaluation of changing trends in ecological integrity. Abiotic (driver) and biotic (responder) indicator components were used in order to identify and monitor any changes in the surrounding environment as well as to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Driver components include water quality, sediment grain size, moisture and organic content as well as habitat state, whereas responder components involve macroinvertebrates and fish assemblages. Two surveys were carried out; one during the low-flow period (5-11 August 2011) and the other during the high-flow period (20-28 March 2012). Current data and findings together with historical data from 1999 to 2010 were used to establish trends of selected driver and responder components. Water quality variables selected include general variables such as water temperature, chemical oxygen demand (COD), electrical conductivity (EC), pH and total alkalinity (TAL) as well as salts, nutrients and toxics. These variables provide indications as to the state of the water-quality component of this study. The Target Water Quality Requirements (TWQR) as developed by the Department of Water Affairs and Forestry for domestic use (Volume 1) and Aquatic Ecosystems (Volume 7) were used to evaluate the quality of the water sampled in this study. The water quality as well as quantity was also compared to historical data obtained from previous studies that have been done for the same study area. The sediment analyses were performed according to the protocol set out by the United States Environmental Protection Agency. Habitat availability, diversity and state were assessed by means of the Integrated Habitat Assessment System Version 2 (IHAS v 2) and the Index of Habitat Integrity (IHI). The water quality of the lower Amatikulu River was found to be in a slightly modified state with the majority of water quality parameters within the target values as set by the TWQG. Water quality parameters considered on the lower Thukela River such as water temperatures, oxygen levels, nutrient and salt loads occurred at elevated levels and were not within the TWQG requirements. The water quality of the Thukela River wasconsidered to be in a modified state which may cause negative impacts on the structure and function of the river, while the water quality of the lower Umvoti River was seriously modified. Sediment analyses revealed that the organic content of the Lower Amatikulu, Thukela and Umvoti Rivers was low. Sediment grain-size distributions are dominated by well-sorted larger soil grain-sizes (>500 μm) which is not ideal for the biodiversity. This is an indication that erosion and transportation are taking place in the Amatikulu, Thukela and Umvoti Rivers. The removal of riparian vegetation by agricultural activities and water abstraction contributes to the habitat deterioration as well as erosion and transportation of sediments that occurs in lower Amatikulu, Thukela and Umvoti Rivers. The use of macroinvertabrates as biological indicators in the determination of the ecological integrity, state or health of lotic ecosystems is globally well established. The South African Scoring System, version 5 (SASS 5), the Macroinvertebrate Response Assessment Index (MIRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Results revealed that the SASS 5 integrity classes were generally one class higher than the integrity classes of MIRAI. SASS 5 and MIRAI integrity classes of the Amatikulu River ranged from natural (Class A) to largely modified (Class D/E) while the Thukela and Umvoti rivers ranged from natural to seriously modified (Class E/F). Fish assemblages are commonly used as key indicators to describe the ecological state of aquatic ecosystems. Methods used to sample fish included electronarcosis and a 5m wide 12mm meshed seine net. The Fish Response Assessment Index (FRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti rivers. Results revealed that the automated FRAI integrity classes were constantly lower than the adjusted FRAI integrity classes. Automated and adjusted FRAI integrity classes of the Amatikulu River ranged from largely natural (Class B) to largely modified (Class D) while the Thukela and Umvoti rivers ranged from natural (Class A) to seriously modified (Class E/F). The current ecological integrity of the lower Amatikulu River was found to be in a largely natural, with few modifications (Class B) state. The Thukela River was found to be in a moderately modified (Class C) state while the Umvoti River was found to be in a largely modified (Class D) state. The trends in ecological integrity of the selected driver components which include water quality, sediment and habitat availability fluctuated noticeably. The general trend in water quality of the lower Amatikulu, Thukela and Umvoti Rivers slightly recovered towards 2012. Sediment analyses revealed that the sediment grain-size distribution as well as the moisture and organic contents generally remained stable. There was a decline in the general state of habitat integrity towards 2012. As a result of the decline in the habitat ecological integrity the ecological integrity of macroinvertebrates also slightly declined towards 2012. However, a noticeable improvement in the ecological integrity of fish assemblages was observed towards 2012. To conclude, the ecological integrity of water quality and fish assemblages improved towards 2012, while habitat and macroinvertebrates deteriorated and sediment stayed the same. The general and overall state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers did not deteriorate nor did it improve, but rather it stayed the same. Impacts on the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers include a multitude of different sources. To prevent the current ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers from deteriorating further, a collective effort involving all parties is essential. / MSc (Zoology), North-West University, Potchefstroom Campus, 2013
28

An ecological integrity assessment of the lower Amatikulu, Thukela and Umvoti rivers, KwaZulu-Natal, South Africa / Johannes Jacobus Venter

Venter, Johannes Jacobus January 2013 (has links)
The ecosystem services of the lower Amatikulu, Thukela and Umvoti Rivers are used extensively through sugarcane agricultural activities, heavy industries and rural sewage-treatment works. These activities affect the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. The Umvoti River is already being referred to as a „working river‟. This study aims to determine the current state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers and to establish trends between current and historical periods for the evaluation of changing trends in ecological integrity. Abiotic (driver) and biotic (responder) indicator components were used in order to identify and monitor any changes in the surrounding environment as well as to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Driver components include water quality, sediment grain size, moisture and organic content as well as habitat state, whereas responder components involve macroinvertebrates and fish assemblages. Two surveys were carried out; one during the low-flow period (5-11 August 2011) and the other during the high-flow period (20-28 March 2012). Current data and findings together with historical data from 1999 to 2010 were used to establish trends of selected driver and responder components. Water quality variables selected include general variables such as water temperature, chemical oxygen demand (COD), electrical conductivity (EC), pH and total alkalinity (TAL) as well as salts, nutrients and toxics. These variables provide indications as to the state of the water-quality component of this study. The Target Water Quality Requirements (TWQR) as developed by the Department of Water Affairs and Forestry for domestic use (Volume 1) and Aquatic Ecosystems (Volume 7) were used to evaluate the quality of the water sampled in this study. The water quality as well as quantity was also compared to historical data obtained from previous studies that have been done for the same study area. The sediment analyses were performed according to the protocol set out by the United States Environmental Protection Agency. Habitat availability, diversity and state were assessed by means of the Integrated Habitat Assessment System Version 2 (IHAS v 2) and the Index of Habitat Integrity (IHI). The water quality of the lower Amatikulu River was found to be in a slightly modified state with the majority of water quality parameters within the target values as set by the TWQG. Water quality parameters considered on the lower Thukela River such as water temperatures, oxygen levels, nutrient and salt loads occurred at elevated levels and were not within the TWQG requirements. The water quality of the Thukela River wasconsidered to be in a modified state which may cause negative impacts on the structure and function of the river, while the water quality of the lower Umvoti River was seriously modified. Sediment analyses revealed that the organic content of the Lower Amatikulu, Thukela and Umvoti Rivers was low. Sediment grain-size distributions are dominated by well-sorted larger soil grain-sizes (>500 μm) which is not ideal for the biodiversity. This is an indication that erosion and transportation are taking place in the Amatikulu, Thukela and Umvoti Rivers. The removal of riparian vegetation by agricultural activities and water abstraction contributes to the habitat deterioration as well as erosion and transportation of sediments that occurs in lower Amatikulu, Thukela and Umvoti Rivers. The use of macroinvertabrates as biological indicators in the determination of the ecological integrity, state or health of lotic ecosystems is globally well established. The South African Scoring System, version 5 (SASS 5), the Macroinvertebrate Response Assessment Index (MIRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers. Results revealed that the SASS 5 integrity classes were generally one class higher than the integrity classes of MIRAI. SASS 5 and MIRAI integrity classes of the Amatikulu River ranged from natural (Class A) to largely modified (Class D/E) while the Thukela and Umvoti rivers ranged from natural to seriously modified (Class E/F). Fish assemblages are commonly used as key indicators to describe the ecological state of aquatic ecosystems. Methods used to sample fish included electronarcosis and a 5m wide 12mm meshed seine net. The Fish Response Assessment Index (FRAI) and multivariate statistical analyses were implemented in order to determine the ecological integrity of the lower Amatikulu, Thukela and Umvoti rivers. Results revealed that the automated FRAI integrity classes were constantly lower than the adjusted FRAI integrity classes. Automated and adjusted FRAI integrity classes of the Amatikulu River ranged from largely natural (Class B) to largely modified (Class D) while the Thukela and Umvoti rivers ranged from natural (Class A) to seriously modified (Class E/F). The current ecological integrity of the lower Amatikulu River was found to be in a largely natural, with few modifications (Class B) state. The Thukela River was found to be in a moderately modified (Class C) state while the Umvoti River was found to be in a largely modified (Class D) state. The trends in ecological integrity of the selected driver components which include water quality, sediment and habitat availability fluctuated noticeably. The general trend in water quality of the lower Amatikulu, Thukela and Umvoti Rivers slightly recovered towards 2012. Sediment analyses revealed that the sediment grain-size distribution as well as the moisture and organic contents generally remained stable. There was a decline in the general state of habitat integrity towards 2012. As a result of the decline in the habitat ecological integrity the ecological integrity of macroinvertebrates also slightly declined towards 2012. However, a noticeable improvement in the ecological integrity of fish assemblages was observed towards 2012. To conclude, the ecological integrity of water quality and fish assemblages improved towards 2012, while habitat and macroinvertebrates deteriorated and sediment stayed the same. The general and overall state of ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers did not deteriorate nor did it improve, but rather it stayed the same. Impacts on the ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers include a multitude of different sources. To prevent the current ecological integrity of the lower Amatikulu, Thukela and Umvoti Rivers from deteriorating further, a collective effort involving all parties is essential. / MSc (Zoology), North-West University, Potchefstroom Campus, 2013
29

Seleção de indicadores ecológicos para a avaliação de planos de restauração de áreas degradadas / Selection of indicators for ecological assessment of plans restoration of degraded areas

Fonseca, Vitor Hugo de Campos 16 June 2012 (has links)
Made available in DSpace on 2016-06-02T19:26:19Z (GMT). No. of bitstreams: 1 FONSECA_Vitor_2011.pdf: 1402147 bytes, checksum: 68adc13f57d441da94e1f7a4fe5bc04d (MD5) Previous issue date: 2012-06-16 / Ecological indicators are useful tools for forest monitoring. It is known that most restoration projects are doomed to failure due to factors of multiple spheres, and lead to a succession challenge course desirable. The practical relevance of the concept of ecological integrity objectives directed this study that, in general seeks to define practical indicators that can express the conditions of the areas restored in the early stages of restoration (up to 5 years). The indicators were rated from 0 to 3, according to criteria such as ease of measurement, degree of variation of response, ability to predict changes in the system, and weights of 1 to 3, given the degree of importance of each attribute of the indicators . The product of the note by the weight of each indicator expressed a measure of its efficiency (EF). In relation to indicators of composition, structure and function in each area, the AE2 was the one that appeared in better health. In relation to indicators of composition, structure and function of the area Itu (AE2) which was presented in a better position when compared to AE1. Among the indicators of composition, richness, diversity (H ') and the presence of exotic species were the most effective attributes, in relation to the structure, attributes were more effective tree density, the average annual increment of the variables and the dendrometric the indicator function, land cover, competition and sanity were more efficient in detecting changes and changes in areas so fast, convenient and understandable. / Indicadores ecológicos são ferramentas úteis para o monitoramento florestal. Sabe-se que a maioria dos projetos de restauração são fadados ao insucesso devido a fatores de múltiplas esferas, sendo um desafio conduzir a sucessão a rumos desejáveis. A relevância prática do conceito de integridade ecológica direcionou os objetivos deste estudo que, de forma geral busca definir indicadores práticos que possam exprimir as condições das áreas restauradas em fase inicial de restauração (até 5 anos). Os indicadores receberam notas de 0 a 3, de acordo com critérios, tais como facilidade de mensuração, grau de variação da resposta, capacidade de prever alterações no sistema, e pesos de 1 a 3, devido ao grau de importância de cada atributo dos indicadores. O produto da nota pelo peso de cada indicador exprimiu a medida de sua eficiência (EF). Em relação aos indicadores de composição, estrutura e função em cada área, a AE2 foi a que se apresentou em melhores condições de integridade. Em relação aos indicadores de composição, estrutura e função a área de Itu (AE2) foi a que se apresentou em melhores condições quando comparada a AE1. Dentre os indicadores de composição, a riqueza, a diversidade (H´) e a presença de espécies exóticas foram os atributos mais eficientes; em relação à estrutura, os atributos mais eficientes foram a densidade de arbóreas, o incremento médio anual das variáveis dendrométricas e quanto ao indicador de função, a cobertura do solo, a competição e a sanidade foram mais eficientes em detectar mudanças e alterações nas áreas de modo rápido, prático e compreensível.
30

Le zooplancton comme bioindicateur de l’état trophique et de l’intégrité écologique des lacs du Parc du Mont-Tremblant

Chemli, Abir 01 1900 (has links)
La gestion et le suivi des écosystèmes dans les parcs nationaux et provinciaux visent essentiellement la préservation de leur intégrité écologique et de leur biodiversité. Toutefois, le portrait de la biodiversité aquatique dans les lacs des parcs nationaux du Québec est encore incomplet, en particulier pour les microorganismes qui forment la base des réseaux trophiques. Ce mémoire présente les résultats de la première étude d’envergure sur le zooplancton de 14 lacs du parc national du Mont-Tremblant (PNMT, Québec), intégrant des connaissances nouvelles sur la biodiversité et la structure taxonomique et fonctionnelle du zooplancton et l’application d’indices biotiques. Le but final est d’établir les relations entre la structure du zooplancton et l’état trophique des lacs afin de mieux évaluer leur niveau d’intégrité biologique. La diversité et la structure du zooplancton et les patrons de dominance des espèces dans les lacs du PNMT sont similaires à ceux observés dans les lacs du Bouclier Canadien en Ontario et au Québec. On distingue plusieurs groupes de lacs sur la base des espèces de rotifères (Kellicottia longispina et Conochilus unicornis) et de cladocères de petite (Bosmina, Diaphanosoma birgei) ou grande (Daphnia catawba, Holopedium gibberum) taille. Les lacs se répartissent le long d’un gradient inverse dans l’abondance des rotifères et des copépodes calanoïdes. Ces taxons présentent le meilleur potentiel de bioindicateurs de l’état trophique des lacs du PNMT. L’altitude, la taille et la profondeur des lacs et la présence de l’Omble de fontaine ou du Grand brochet ont un effet structurant sur le zooplancton. Ils permettent de classer les lacs du PNMT en deux groupes bien distincts : i) les lacs oligotrophes à Omble de fontaine riches en copépodes calanoïdes (Allen, Herman, du Brochet, Obéron et Trap), ii) les lacs oligo-mésotrophes à Grand brochet (avec des cyprins planctivores) plus riches en rotifères (surtout Desjardins, Savane, Houdet, Monroe et Rossi). / The application of environmental management plans and monitoring programs in national parks aims essentially to preserve biodiversity and ecological integrity of natural ecosystems for future generations. However, knowledge on aquatic biodiversity in national parks in Quebec is still incomplete, especially for the microorganisms at the base of food webs. This research presents the first important study on the zooplankton communities in 14 lakes of the Parc National du Mont-Tremblant (PNMT, Québec), including new knowledge on the biodiversity components, the taxonomic and functional structure of zooplankton communities, and the application of biotic indexes. The ultimate goal is to establish the relationships between trophic state and both zooplankton community structure and the derived biotic indexes, in order to evaluate the ecological integrity of the study lakes. Biodiversity components and zooplankton community structure of the PNMT lakes are similar to those observed in Canadian Shield lakes in Ontario and Québec. We could distinguish two groups of lake based on rotifer species (Kellicottia longispina and Conochilus unicornis) and on cladoceran species of small (Bosmina, Diaphanosoma birgei) or large (Daphnia catawba, Holopedium gibberum) size. Lakes are distributed along inverse gradients of the relative abundance of rotifers and calanoid copepods. These taxa offer the best potential as bioindicators of the trophic state and ecological integrity of PNMT lakes. Three main factors (altitude, area and depth of lakes, and the presence of brook trout or northern pike) are structuring zooplankton community in two main groups: i) the oligotrophic lakes with the brook trout dominated by the calanoid copepods (Allen, Herman, du Brochet, Obéron and Trap), ii) the mesotrophic lakes with the northern pike (including planktivore cyprinids) dominated by rotifers (mainly Desjardins, Savane, Houdet, Monroe and Rossi).

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