Spelling suggestions: "subject:"[een] ECOLOGICAL RESTORATION"" "subject:"[enn] ECOLOGICAL RESTORATION""
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Enhancement of Concretized Streams: Mill CreekKordenbrock, Brett Nathan 24 July 2013 (has links)
No description available.
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Natural Revegetation of an Aged Petroleum Landfarm Impacted With Polycyclic Aromatic Hydrocarbons (PAHs) and Heavy Metals (Cr, Pb, Zn, Ni, Cu): Ecological Restoration, Remediation, and RiskHenry, Heather Fort January 2004 (has links)
No description available.
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Dynamique des communautés biologiques dans un contexte de restauration par injection sédimentaire et érosion maitrisée : cas du Vieux Rhin, France / Dynamics of biological communities in a context of restoration by gravel augmentation and controlled erosion : the case of the Old Rhine River, FranceStaentzel, Cybill 25 April 2018 (has links)
Le Rhin a subi d’importantes modifications qui ont altéré la biodiversité de l’ensemble de la plaine alluviale. Des actions de restauration ont été initiées pour lui redonner une part de son fonctionnement hydromorphologique naturel. Le travail de thèse a consisté à évaluer les effets de ces restaurations et à mettre en évidence les processus mis en jeu dans les changements de la biocénose des milieux restaurés. Les résultats ont démontré que les communautés biologiques sont non seulement gouvernées par les modifications physiques post-restauration mais aussi par l’influence discrète de déterminants externes à la restauration tels que les invasions biologiques ou la dynamique interne du fleuve. L’aspect transitoire des bénéfices obtenus a été souligné comme la principale limite de l’injection sédimentaire alors que les épis transversaux artificiels mis en place dans le cadre d’un essai d’érosion maitrisée se sont révélés être les facteurs de durabilité des effets écologiques. / The Rhine River has undergone major engineering works that led to severe alterations which helped to alter the biodiversity of the entire floodplain. Restoration actions have been initiated to give it back a part of its natural hydro morphological functioning. The thesis consisted in evaluating the effects of these restorations and in highlighting the mechanisms and processes involved in biocoenosis changes of the restored environments. The results also showed that the post-restoration biological community is not only defined by post-restoration physical changes but also by the discrete influence of external determinants of restoration such as biological invasions or the internal dynamics of the river. The transitional aspect of the benefits incurred has been identified as the main limit of the gravel augmentation, while the implementation of transverse artificial groynes in the controlled bank erosion has proved to be factors of sustainability of the ecological effects.
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Approches géomorphologiques historique et expérimentale pour la restauration de la dynamique sédimentaire d'un tronçon fluvial aménagé : le cas du Vieux Rhin entre Kembs et Breisach (France, Allemagne) / Historical and experimental geomorphology for the process-based restoration of a modified fluvial system : the Old Rhine between Kembs and Breisach (France, Germany)Arnaud, Fanny 10 December 2012 (has links)
Le Rhin dans son parcours franco-allemand a été aménagé depuis deux siècles pour la protection contre les inondations, la navigation et la production hydro-électrique. La rectification (19ème siècle), la régularisation (1930) et la construction du Grand Canal d’Alsace (1928-1959) ont profondément altéré le fonctionnement hydro-sédimentaire du « Vieux Rhin », tronçon de 50 km court-circuité entre les barrages de Kembs et de Breisach, conduisant à une réduction de la complexité du tracé en plan, une incision, un pavage du fond du lit et une simplification des habitats aquatiques et riverains. La possibilité de restaurer le transport sédimentaire et la dynamique alluviale du Vieux Rhin est évaluée au sein de projets portés par la Région Alsace et EDF. Dans ce cadre, la présente thèse repose sur deux types d’approches de la géomorphologie fluviale, historique et expérimentale, afin de répondre à la problématique de restauration morpho-écologique du tronçon fluvial. Ce travail, basé sur la collecte de données anciennes et de terrain, ainsi que sur la quantification des évolutions morphologiques à différents niveaux scalaires, a conduit à une meilleure compréhension de la trajectoire temporelle d’ajustement de l’hydrosystème et à une estimation de sa sensibilité aux changements. Le suivi géomorphologique d’un test de recharge sédimentaire conduit sur un site-pilote a servi également à évaluer la pertinence de ce type d’intervention, à travers l’analyse des bénéfices et des risques environnementaux potentiels. L'ensemble des résultats obtenus a permis d’apporter aux gestionnaires des éléments d'aide à la réflexion pour orienter les stratégies de restauration ainsi que des indicateurs physiques d’évaluation des futures actions / The Upper Rhine River has undergone several anthropogenic modifications since the last two centuries for flood protection, navigation and hydropower generation. Channel rectification, groyne fields and lateral “Grand Canal of Alsace” construction heavily altered the hydro-sedimentary functioning of the 50 km-long "Old Rhine" by-passed between Kembs and Breisach: channel pattern simplification, bed incision, armouring and ecological habitats alterations. Two complementary projects have been initiated to restore the sediment transport and the reach alluvial dynamics. This thesis investigated space-time and experimental geomorphic approaches within the morpho-ecological restoration of a modified fluvial system. The archive and field data-based work aimed at understanding the Old Rhine historical trajectory. The geomorphological monitoring of a gravel input experiment also consisted in evaluating environmental benefits and potential risks for society and proposing physical assessment indicators. Results will help river stakeholders to define strategies to restore morphological processes and associated ecological functions in the Old Rhine.
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Restauration écologique de prairies humides à vocation agricole suite au comblement d'une ballastière en basse vallée de Seine : incidence du type de sol recréé sur les fonctions pédologiques associées et sur la dynamique de colonisation végétale / Ecological restoration of wet agriculture-oriented meadows after the filling of a ballast-pit in the Lower Valley of the Seine River : incidence of the recreated soil type on the pedological associated functions and on the dynamic of plant colonisationBoigné, Audrey 04 April 2017 (has links)
Dans un contexte de destruction des zones humides à l’échelle mondiale, conséquence des activités d’origine anthropique, la restauration écologique de ces milieux et de leurs fonctions est devenue un enjeu écologique et sociétal. L’objectif de ce projet est de recréer des prairies humides à vocation agricole aux caractéristiques pédologiques et floristiques aussi proches que possible de celles des prairies totalement détruites par l’exploitation de matériaux alluvionnaires. L’étude présentée ici se focalise sur l’incidence des matériaux pédologiques utilisés pour la recréation de quatre sols sur les fonctions du sol et les cortèges floristiques associés. L’hypothèse principale est que la recréation d’un sol morphologiquement proche de celui détruit devrait permettre d’orienter la restauration écologique.L’hypothèse sous-jacente est qu’en utilisant différents matériaux pédologiques locaux, on hérite de leurs caractéristiques physico-chimiques et biologiques ce qui permettait de conserver les fonctions pédologiques qui leur sont associées et favorisait le retour d’un cortège floristique compatible avec un usage agricole. La première partie est consacrée à l’étude de deux fonctions remplies par les sols de zones humides à savoir le stockage du carbone organique et la dénitrification. Deux années et demi après la fin des travaux de comblement de ballastières, ces deux fonctions sont conservées au sein des quatre types de sols recréés. Les principaux résultats montrent un niveau d’efficience des matériaux pédologiques testés, fonction de leur sol origine et de leurs caractéristiques physico-chimiques. La deuxième partie est consacrée à l’étude des mécanismes de structuration des communautés végétales. Le suivi de la colonisation spontanée de la végétation a permis d’appréhender la forte contribution de la banque de graines issue des matériaux pédologiques locaux. Malgré la mise en évidence d’un début de trajectoires dynamiques au sein des quatre sols recréés, la similarité entre les communautés obtenues et les communautés cibles des prairies de référence n’excède pas 50 %. Les productions de biomasses aériennes associées à ces communautés sont comparables en quantité à celles des prairies de référence mais pas en qualité. La mise en place d’une gestion par semis associée à une fauche montre dès la première année une production de biomasses de qualité se rapprochant de celles des prairies locales.La dernière partie de ce manuscrit est consacrée à l’effet de trois niveaux d’engorgement des sols sur le processus de dénitrification et sur les traits de réponse d’une espèce prairiale, Holcus lanatus. Placer les quatre matériaux pédologiques dans des conditions identiques d’engorgement permet de souligner l’importance de l’héritage des communautés bactériennes dénitrifiantes sur le processus de dénitrification. Parallèlement, ces conditions expérimentales permettent de mettre en évidence les traits de réponses morphologiques et fonctionnels de l’espèce considérée. À l’issue de ces suivis, le meilleur compromis de restauration alliant sol, végétation et coûts économiques doit prendre en considération l’origine et l’histoire (i.e. gestion) des matériaux utilisés lors de la recréation écologique. / In a worldwide context of wetland destruction, a consequence of anthropic activities, ecological restoration of such habitats and their functions has become a societal and ecological issue. The objective of this project is to recreate agriculture-oriented wet grasslands with pedological and floristical properties as similar as possible to typical grasslands destroyed by alluvial materials extraction. The study presented here focuses on the impact of pedological materials, used in the re-creation of four soils, on soil functions and associated floristic processions. The main hypothesis is that re-creation of a soil morphologically similar to the previously destroyed one should drive ecological restoration. The underlying hypothesis is that different local pedological materials inherit their previous physicochemical and biological properties. This should conserve associated pedological functions and favor the return of a floristic procession compatible with agricultural exploitation. The first part is dedicated to the study of carbon storage and denitrification, two wetlands soils functions. These two functions are retained within the four re-created soils two and a half year after gravel-pit filling. Main results highlight functional efficiency levels of tested pedological material inherited from their respective initial topsoil physico-chemical properties. The second part is devoted to the study of mechanisms structuring plant communities. The high contribution of local pedological materials seed bank during the colonization process and its impact on aforementioned mechanisms was highlighted from our monitoring. Despite demonstration of the start of a dynamic trajectory in the four created soils similarity between obtained and target communities never exceeds 50%. Aerial biomass production associated to these communities is comparable to the production in reference wet grasslands in terms of quantity, but not quality. Implementation of management (sowing and mowing) shows biomass production of comparable quality to reference grassland from the first year onwards. The last part focuses on the effect of three soil waterlogging levels on the denitrification process and the response traits of Holcus lanatus, a meadow species. Pedological materials placement in identical waterlogging conditions highlights the importance of denitrifying bacteria communities inheritance on the denitrification process. These experimental conditions also enabled us to highlight the considered species morphological and functional response traits. To conclude and following our monitoring the best compromise for concurrent restoration of soil and vegetation while considering cost-effectiveness needs to account for topsoils origin and history (i.e. management).
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Factors affecting the establishment, growth and survival of native woody plant communities on the Canterbury Plain, New ZealandPratt, Caroline January 1999 (has links)
The native plant communities of Canterbury, South Island, New Zealand have been severely modified and degraded and the Canterbury Plain (750,000 ha) retains few remnants of its original forest and other ecosystems. The research presented here considers the mutualistic roles of exotic and indigenous species in the process of restoring degraded landscapes. Exotic species may have an important role in the (re) establishment of desired indigenous species, and may influence succession through to a forest dominated by them. One aspect of this work describes indigenous plant community regeneration facilitated by exotic willow (Salix spp.) woodland on the Canterbury Plain. Natural colonisation of the willow woodland by native plants was investigated, with respect to variation in the physical environment in the willow stand. Key factors in the success of willow woodland as a nursery for regeneration of native vegetation include: distance to the nearest seed source, the ability to attract seed dispersers (recruitment only occurred under perch sites), flooding potential (higher recruitment in areas less likely to flood) and possibly light availability. Control of vertebrate (and invertebrate) herbivory is also necessary for successful restoration. A second aspect was a field experiment in open pasture and in a non-native remnant woodland which was then used to investigate the effects of shelter, plant spacing, mulching and fertiliser on growth and survival of planted native woody species. With minimal management, the selected mid-late successional plants established poorly in the open pasture and had low survival rates (e.g.,Dacrycarpus dacrydioides, Pseudopanax arboreus, Aristotelia serrata, Melicytus ramiflorus). Only narrow-leaved species (e.g., Plagianthus reg ius, Hoheria angustifolia, Hebe salicifolia, Cordyline australis) survived this open pasture planting. In contrast, most species (broad and narrow-leaved) established under the sheltered sites. Exotic nursery vegetation and the establishment of native species, which will, in time, act as a seed source, will be important in successfully restoring a sustainable indigenous element in the cultural landscape of Canterbury. Ecological restoration requires an integrated approach, identifying and understanding the component processes of regeneration, and of the particular aspects/characteristics of the sites involved. This research shows that naturally established plants where existing shelter is available (in this case established willows) tend to have higher growth rates than individually planted plants in open situations, and that the availability of a suitable seed source can also contribute to successful establishment and growth rates. The meeting of restoration targets on the Canterbury Plain may be accelerated, and costs reduced, through the utilisation of areas where exotic species occur (for instance, extensive willow stands in riparian areas adjacent to waterways) and more particularly, where a local seed source is also available. The findings of this research can contribute to restoration management in helping identify the best practices, based on research, that can lead to the restoration of original plant and animal communities.
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Rekultivace území zasažených těžbou a jejich možné začlenění do projektu KPÚ / Reclamation of land affected by mining and their possible integration into project of comprehensive land adjustmentMATOUŠKOVÁ, Jana January 2015 (has links)
The aim of this thesis is detailed description of solved reclamation in the selected location Cep II after gravel extraction. The part of thesis solves property settlements on the parcels concerned. The literary review outlines generally issue of mining and its impact on the landscape and ways of deal with these negative impacts. Besides the classical methods of reclamation (agricultural, forestry and hydrological reclamation) is described a method of using spontaneous restoration. There is also particularised the possibility of incorporating suitably reclaimed parcels into territorial system of ecological stability in terms of land adjustment.
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Polímeros de hidrogéis com água de reúso e de abastecimento no desenvolvimento de mudas de espécies arbóreas da floresta estacional semidecidualFerreira, Alexandre José Domingues 07 August 2014 (has links)
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Previous issue date: 2014-08-07 / Universidade Federal de Sao Carlos / The seasonal semideciduous forests from southeastern Brazil have high plant species richness, but have been strongly affected by human interferences, which let them very degraded: nowadays they are represented by small isolated fragments, immersed in a landscape dominated by agriculture and large urban centers. In this sense, the ecology of restoration arises in order to facilitate, accelerate and direct the processes of secondary succession to manage such areas, considering the knowledge about theoretical concepts that aim to review the effectiveness of natural ecosystem management techniques and practices. In such a perspective, we aimed in this experiment to test the following question: During de production of seedlings of the native forest tree species, Ceiba speciosa (Malvaceae) and Handroanthus heptaphyllus (Bignoniaceae), different dilutions of hydrogel associated to irrigation with reused water, could improve their development? To answer this question, we selected three treatments (1g, 4g and 8g of hydrogel), beyond the witness (no hydrogel). The seedlings of both species were irrigated during one month with water reused and water supply. After this period, we estimated the growth of seedlings: roots, height and diameter. We used ANOVA (p = 0.001), and Tukey s test to verify significative differences between the mean of the treatments. We found significative differences in both height and diameter growth from 4g of hydrogel as to C. speciosa as H. heptaphyllus. In relation to the growth of root system of both tree species, the mean of superficial root area differed significantly from 4g of hydrogel when compared to the witness, confirming our initial assumption that the roots would grow in a lower proportion of area because they are in their hydric comfort zone. With such results added to theoretical knowledge in the ecology of restoration, the association of hydrogels with reused water comes to stand up for the sustainable use of water in the irrigation of native seedlings. / Apesar das florestas estacionais semideciduais do interior do estado de São Paulo possuir elevada riqueza de espécies, as interferências humanas deixaram esses ecossistemas degradados e representados por pequenos fragmentos isolados, imersos numa paisagem dominada pela agricultura e centros urbanos. Diante essa problemática, a restauração ecológica surge com o objetivo de facilitar, acelerar e direcionar os processos sucessionais naturais a fim de manejar essas áreas, considerando os novos teóricos da ecologia de comunidades vegetais tropicais, que pretendem revisitar a eficácia de técnicas de manejo em restauração ecológica. Nesta perspectiva, surge como objetivo desse trabalho, testar a pergunta científica: O uso de polímeros hidrogéis em diferentes concentrações na produção de mudas nativas de Ceiba speciosa (Malvaceae) e de Handroanthus heptaphyllus (Bignoniaceae), associados à irrigação com água de reúso tratada, interfere significativamente no crescimento de seu sistema radicular, sua altura e diâmetro, e aumenta a longevidade das mudas? Para responder a essa pergunta, utilizou-se mudas das duas espécies nativas, em três tratamentos (1g, 4g e 8g de hidrogel), além da uma testemunha, contendo apenas o solo. As mudas foram irrigadas por um mês com água de abastecimento e água de reúso tratada; depois de cessadas as irrigações, foram avaliadas os estimadores citados. Foram realizadas análises de variância (p = 0,001), seguidas do teste de Tukey para verificar diferenças significativas entre as médias dos tratamentos. Verificaram-se diferenças significativas no crescimento em altura e diâmetro a partir do uso de 4g de hidrogel, tanto para C. speciosa quanto para H. heptaphyllus. Em relação ao sistema radicular, as médias de área superficial diferiram-se estatisticamente a partir de 4g de hidrogel quando comparadas às testemunhas, tanto para C. speciosa quanto para H. heptaphyllus, confirmando a expectativa inicial de que com hidrogel, as raízes cresceriam em menor proporção em área porque estariam na zona de conforto hídrico. Com esses resultados aliados aos conhecimentos teóricos da ecologia da restauração, a associação de polímeros hidrogéis com água de reúso vem defender a racionalização do uso da água na irrigação de mudas de espécies nativas, reaproveitando águas de reúso que seriam descartadas em águas superficiais.
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Analyse spatio-temporelle de la morphologie du chenal du Rhône du Léman à la Méditerranée / Spatio-temporal analysis of the Rhone channel morphology from Geneva Lake to the Mediterranean SeaParrot, Elsa 17 December 2015 (has links)
Cette thèse étudie l’organisation longitudinale du lit du Rhône français et son évolution depuis plus d’un siècle afin d’améliorer la gestion des sédiments du fleuve. Elle décrit d’abord la complexité géographique, géologique, et hydrologique des 512 km du système fluvial. Les extractions, l’endiguement, la chenalisation et les aménagements hydroélectriques ont simplifié le tracé latéral du chenal, incisé et pavé le fond du lit et appauvri les habitats aquatiques et riverains. La thèse caractérise ensuite plus précisément les dynamiques de fond. Elle repose sur des données bathymétriques de 1897-2010 et sur des données granulométriques issues de plus de 300 prélèvements réalisés dans le cadre de ces travaux sur l’ensemble du linéaire. Un protocole d’échantillonnage homogène a été spécialement élaboré. Les variations altimétriques du lit (zones de stockage-érosion et faciès morphologiques) et sa composition granulométrique (zones pavées ou comblées par des fines) ont été caractérisées afin d’évaluer la mobilité potentielle de la charge de fond, les apports des affluents et l’impact des ouvrages sur les conditions de transport. Il ressort 1) que l’incision du lit est principalement due à la chenalisation, 2) que les aménagements hydroélectriques ont compartimenté le continuum en provoquant le stockage de sédiments fins dans certaines retenues et en favorisant le pavage dans les vieux Rhône à l’aval de Lyon et 3) qu’une dynamique résiduelle subsiste lors de crues majeures avec une remobilisation modérée de la charge de fond. Les données des secteurs les plus pavés ont été intégrées dans un modèle hydraulique 1D permettant de quantifier la capacité de transport et le débit solide et confirmant les résultats précédents. Ces travaux permettent de formuler des recommandations de gestion durable et de restauration écologique du fleuve telles que l’ouverture des vannes de fond en crue, la modification des consignes aux barrages ou la réinjection de graviers. / This thesis studies the French Rhone riverbed longitudinal organisation and its evolution over a century, with a view to improve the management strategy for the sediments. It first describes the geographic, geologic and hydrologic peculiarities of the 512-km long fluvial system. Gravel mining, dikes construction, channelization and dams construction have simplified the lateral pattern of the channel, incised and paved the riverbed and impoverished the aquatic and riparian habitats. The thesis then more precisely characterizes the riverbed dynamics. It relies on bathymetric data collected since 1897 and on grainsize data collected specifically for this study from over 300 samples on the whole 512-km river length. An homogeneous sampling protocol was elaborated on purpose. The vertical bed evolution and grainsize distribution were analysed to assess the riverbed potential mobility, tributaries’ sediment recharge and infrastructures’ impact on sediment transport. It thus appears that 1) riverbed incision is mainly due to channelization, 2) hydroelectric dams partitioned the continuum with the accumulation of fine sediments in some backwaters and the pavement of bypassed reaches downstream of Lyon and 3) a residual dynamic persists during major floods, with moderate gravels transport. The data of paved reaches were used in a 1D hydraulic model to quantify transport capacity and bedload discharge, confirming the aforementioned results. This study helps formulate such recommendations for sustainable river management and ecological restoration as opening slush gates during floods, changing dams management instructions or reinjecting gravel.
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Quantifying Impacts of Deer Browsing and Mitigation Efforts on Hardwood Forest RegenerationCaleb H Redick (8067956) 03 December 2019 (has links)
<p>Due to overpopulation and
resource-poor habitat structure, deer threaten the<a>
future of oak and other browse-sensitive species in hardwood forests. </a>Appropriate
tools must be used to ensure desirable, diverse, and ecologically stable
regeneration of future forests and the sustainability of native plant
communities. We performed two experiments and a review to examine the
effectiveness of available methods for managing browse of hardwood seedlings
and to discover how these interact with each other and other silvicultural
methods. First, we examined how fencing interacts with controlled-release
fertilization, seed source (genetically select and non-select), and site type
(afforested and reforested sites) to enhance the regeneration of planted
northern red oak (<i>Quercus rubra </i>L.),
white oak (<i>Quercus alba</i>), black
cherry (<i>Prunus serotina</i>), and black
walnut (<i>Juglans nigra</i>) at five sites in Indiana. Fencing
proved to be the greatest determinant of seedling growth, survival, and
quality. Fertilizer enhanced the early growth of white oak and black cherry, though
for black cherry this occurred only inside fences. Select seed sources grew
better and showed greater quality; however, the survival of select seedlings
was limited by deer browse in absence of fences. Trees at afforested sites had lower survival if left non-fenced. Secondly, we also investigated how fencing and
invasive shrub removal affected natural regeneration, species richness, and
ground-layer plant cover under closed-canopy forests. Honeysuckle (<i>Lonicera maackii</i>)
removal had a variable effect depending on species and site. Positive effects were most common for shade-intolerant species, while negative effects occurred for a few shade-tolerant species at some sites. Deer fencing had a positive effect on
cherry and hackberry seedling density, and a negative effect on elm seedling
density. Honeysuckle and deer fencing interacted antagonistically in some
instances. Fencing without honeysuckle removal resulted in lower elm abundance and herbaceous-layer cover. In the densest invasions, leaving honeysuckle intact
resulted in a complete lack of recruitment into the sapling layer. Our experiment suggests that invasive shrub removal and fencing be done together. Finally,
we synthesized the existing literature on browse management options for
hardwood regeneration to evaluate their relative effectiveness. Fences, tree shelters, repellents, facilitation
by neighboring plants, deer population control, timber harvest, and slash all had positive
effects on height growth of regenerating seedlings under deer browse pressure. Fences
were more effective at reducing browse than repellents, while fertilizers
increased browse and had no effects on growth. </p>
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