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EXAMINING METHODS TO RESTORE AND REHABILITATE NATIVE CANEBRAKE HABITAT IN SOUTHERN ILLINOISNesslar, Richard William 01 August 2018 (has links)
Giant cane (Arundinaria gigantea) is a native bamboo that forms large monodominant stands called canebrakes in bottomlands in the southeastern US. Canebrakes are valuable habitat for wildlife and function as riparian buffers to protect soils and water quality. Currently, only 2% of canebrake ecosystems remain. Thus there is interest in establishing new canebrakes as well as maintaining and expanding existing canebrakes. For field restoration, using cane rhizomes to produce transplants is possible but it is unknown when propagules should be collected and grown. For rehabilitation of existing canebrakes, preliminary studies suggest that fertilization and disturbance such as fire can be beneficial but additional broader-ranging studies are warranted. This research reports on three giant cane studies involving producing transplants from rhizomes and involving managing existing canebrakes with disturbance in southern Illinois. The main objectives of study 1 were to ascertain a) if collection season influences the proportion of rhizome propagules that grow at least one culm (culm production success) and the resultant culm growth when transplanted in a greenhouse b) if specific rhizome characteristics influence an individual rhizome’s ability to produce a culm c) if aboveground biomass could be a predictor of the amount of belowground propagules and d) if aboveground biomass, total rhizome length, number of rhizome nodes, or number of rhizome buds could be a predictor of how many culms could be produced when transplanting. Monthly, for a year, sample plots were randomly selected in the SIUC giant cane nursery. In sample plots aboveground culm measurements were collected included live culm density (#/0.25m2), dead culm density (#/0.25m2), height of the tallest culm (cm), diameter of the tallest culm (mm), and total aboveground biomass (g). Each month rhizomes were dug from the sample plots, measured (length (cm), diameter (mm), # nodes, and # live buds), and transplanted into pots and placed in the greenhouse for approximately 94 days. At that time, measurements were taken of the number of live and dead culms produced per pot and the height of the tallest culm (cm). Results indicate that rhizomes collected and transplanted in the greenhouse during winter and spring months (December-May), had significantly greater culm production success and produced significantly taller culms. Also, rhizomes intermediate in length (18-30 cm) that contained 5 to 12 nodes and 4 to 9 live buds tended to have higher than average culm production. Finally, a positive correlation existed between the amount of aboveground biomass and the number of rhizome nodes, the number of live rhizome buds, and the length of rhizomes found in sample plots. Aboveground biomass can predict the amount of belowground rhizome propagules that can be used for canebrake restoration. Study 2 is a two year continuation of work initiated in 2011 and reported on by Margaret Anderson in 2014 on the effects of fire, fertilization, and fire and fertilization combined on the growth and expansion (culm density, height and diameter) of canebrakes within the Cache River Watershed in southern Illinois. Results showed considerable year to year variability among treatments within the canebrake for some growth parameters. However, three years after disturbance, all treatments tended to have similar culm density and growth values and canebrake expansion occurred for all treatments into exterior plots. Fire alone was similar to controls in growth parameters and did not produce any long-term negative effects. Thus, fire can be used as an effective tool to reduce competition from other species, allowing managed canebrakes to persist longer than those that remain undisturbed. Fertilization used alone and in combination with fire, produced slight growth and density increases, but added costs may not warrant its use in canebrake management. Study 3 compared fire and mowing disturbances on the growth and expansion of remnant canebrakes located in southern Illinois. Eleven replications in remnant canebrakes were established throughout the Cache River watershed. Each replication contained a fire only treatment, a mowing only treatment, and a control. Measurements were taken in the dormant season early in 2012 prior to a single mowing and a single fire in March, and after each growing season thru 2014. Measurements including live and dead culm density (#m2), culm height (cm), and culm diameter (0.01 mm), were taken within subplots in the canebrake interior and exterior. Results from this study showed that mowing can be used as an effective alternative to fire for the management of remnant canebrakes through reductions in competition. Neither fire nor mowing produced negative effects of growth within the measured canebrakes or in adjacent areas. Like the previous study, all treatments including the control experienced an outward expansion of cane culms throughout the course of the study. This study shows that both fire and mowing can be used as effective tools to reduce competition within canebrakes to aid in their continued vigor.
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Land Use Effects on Carbon Cycling in Oregon Coastal WetlandsBlount, Keyyana 10 April 2018 (has links)
Pacific Northwest coastal wetland extent has been significantly reduced due to development. To understand the effects of land use change on carbon cycling in coastal wetlands, we compared soil carbon dynamics in restored, disturbed (by diking or draining), and reference wetlands in both freshwater and saline conditions in Coos Bay, Oregon. We quantified soil carbon pools, measured in situ fluxes of methane (CH4) and carbon dioxide (CO2), and estimated sediment deposition and carbon sequestration rates. We found that land use change influences carbon cycling and storage in coastal wetlands. The disturbed marshes have likely lost all their organic material after draining or diking, except for a shallow A horizon. The restored marsh in situ CH4 and CO2 fluxes were intermediate between the disturbed and reference marshes. Generally, restored marshes showed a partial return of carbon storage functions, or an indication that reference level functions may be achieved over time.
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Se reconstruirmos elas virão? abelhas e vespas solitárias que nidificam em cavidades preexistentes em matas ciliares restauradas no cerrado do Sudeste do Brasil.Araújo, Gustavo Júnior de January 2015 (has links)
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Previous issue date: 2015 / As matas ciliares compõem uma vegetação característica de margem de corpos
d’água, apresentando importantes funções ecossistêmicas, impedindo o assoreamento de
rios, lagos e lagoas, promovendo a estabilidade nos ambientes aquáticos, atuando como
corredores ecológicos e funcionando como importantes áreas de refúgio para diversas
espécies da fauna. Nesse trabalho avaliou-se o sucesso da restauração de quatro
fragmentos de mata ciliar, no entorno do Reservatório da Usina Hidrelétrica de Volta
Grande situada entre os estados de Minas Gerais e São Paulo comparando-as com um
fragmento que passou por processo de sucessão natural. Utilizou-se como indicador a
comunidade de abelhas e vespas solitárias que nidificam cavidades preexistentes.
Avaliou-se a relação entre largura, período de recuperação, matriz adjacente e a
estrutura da vegetação sobre a riqueza, abundância, composição e rede de interação com
parasitas de ninhos. As matas ciliares restauradas apresentaram uma riqueza (s=20) e
abundância (n=368) maiores em relação a vários outros levantamentos em áreas
primárias. A área referência e as áreas com maior largura apresentaram uma maior
riqueza de abelhas e as áreas mais novas apresentaram maior abundância de vespas. A
maior quantidade de fragmentos de cerrado na matriz determinou a maior riqueza e
abundância de abelhas e vespas. Quanto maior a complexidade estrutural da vegetação
nos fragmentos mais diversificada é a comunidade e diferentes espécies responderam de
forma diferente a essa complexidade. As abelhas e vespas solitárias que nidificam em
cavidades preexistentes se mostraram excelentes preditoras de qualidade ambiental,
demonstrando que o processo de restauração das matas ciliares está caminhando para o
sucesso por disponibilizar ambientes para a ocupação da fauna e estar recuperando dos
serviços ecossistêmicos perdidos. __________________________________________________________________________________________ / Riparian forests play an important role in the preservation of water bodies and, in
maintaining biodiversity, act as refuges for many species or can be used as ecological
corridors. The restoration of these environments is critical to the recovery of pollinator communities. In this work we study the role of restored riparian forest on the riverbanks of the Volta Grande Reservoir (MG and SP) in maintaining bees and wasps communities that nest in preexisting cavities so as to verify if here is difference in richness, abundance and composition throughout the seasons (dry and wet), if there is a relationship between richness and abundance of these individuals and their parasites and the degree of specialization of parasites in relation to the hosts. Were recorded 12 species of wasps, eight of bees and nine species of parasites of the orders Coleoptera,
Diptera, Hymenoptera in addition to mites and fungi. The wasps Trypoxylon nitidum
(Smith, 1856), Pachodynerus grandis Willink & Roig-Alsina, 1998 and the bee Centris
(Heterocentris) analis (Fabricius, 1804) were the most abundant. Areas with longer
time of restoration showed higher species richness. However the abundance was higher
in most recent areas. The composition of bees and wasps assembly has not changed
between the four seasonal periods evaluated, although it has changed between sampling
areas. The richness and abundance were higher in warmer and rainy periods. The rate of bee mortality was 45.68% and 48.62% for the wasps. Richness parasites correlated positively with the richness and abundance of bees and wasps. The network of host-
parasite interaction has a modular configuration with generalists and specialists. Recovered riparian forests are providing environmental conditions necessary for the maintenance of bees and wasps communities that nest in preexisting cavities.
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Synthesizing Styles: International Influence on Organ Music in Restoration EnglandJanuary 2014 (has links)
abstract: Following the Restoration of the English monarchy in 1660, musical culture gradually began to thrive under the support of royal patronage and the emerging middle class. The newly crowned Charles II brought with him a love of French music acquired during his time in exile at the court of his cousin, the young Louis XIV. Organ builders, most notably Bernard Smith and Renatus Harris, brought new life to the instrument, drawing from their experience on the Continent to build larger instruments with colorful solo stops, offering more possibilities for performers and composers. Although relatively few notated organ works survive from the Restoration period, composers generated a niche body of organ repertoire exploring compositional genres inspired by late 17th-century English instruments.
The primary organ composers of the Restoration period are Matthew Locke, John Blow, and Henry Purcell; these three musicians began to take advantage of new possibilities in organ composition, particularly the use of two-manuals with a solo register, and their writing displays the strong influence of French and Italian compositional styles. Each adapts Continental forms and techniques for the English organ, drawing from such forms as the French overture and récit pour le basse et dessus, and the Italian toccata and canzona. English organ composers from the Restoration period borrow form, stylistic techniques, ornamentation, and even direct musical quotations, to create a body of repertoire synthesizing both French and Italian styles. / Dissertation/Thesis / Doctoral Dissertation Music 2014
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Restauro de duas casas modernistas como subsídio para um método / Restoration of two modernist houses as input to a methodGiceli Portela Cunico de Oliveira 19 June 2015 (has links)
Pode-se recuar a teorização do restauro de Arquitetura até Winckelmann: sua \"História da Arte\", publicada em Dresde em 1764, apresenta um nível de detalhamento nas descrições e até de processos construtivos gregos e romanos, que transcende as preocupações explícitas com a História da Arte. Seu pensamento é que os remanescentes são os documentos imprescindíveis para se contar a evolução da Arquitetura - nas entrelinhas, ficando a necessidade de sua preservação. No entanto, aceita-se academicamente Ruskin como iniciador da reflexão e teorização. Praticava-se, em seus dias, uma preservação sem critérios seguros que, no seu entendimento, comprometia o valor documental e histórico dos monumentos: as ruínas eram preferíveis a essas obras, entrando aí, como é óbvio, um forte componente do romantismo vigente. Nesse sentido, opunha-se a Violet-le-Duc que defendia como proposta teórica o restauro estilístico. Camillo Boito é quem, na verdade, dá a partida para a teorização que, evoluindo, é a que se aceita até hoje: formula critérios e diretrizes para se pensar o processo de restauro. Suas ideias são desenvolvidas por G.Giovanoni, preparando caminho para as cartas de Atenas e, finalmente, a de Veneza, ainda a \"cartilha\" dos restauradores. Ideias essas que têm sua formulação teórica mais precisa e desenvolvida em Cesare Brandi, em sua \"Teoria da Restauração\". A acelerada evolução tecnológica do século XX - bem como o ingresso, no rol dos bens patrimoniais, das obras do Modernismo - tornou necessário estender a aplicação dos conceitos teóricos às novas tecnologias: - que princípios devem nortear as intervenções restaurativas na Arquitetura Moderna, quando esta estiver focada como patrimônio cultural? - quais as posturas teóricas, quais as reflexões que devem estruturar os pensamentos, antes dos procedimentos técnicos, por parte do arquiteto, diante dos novos problemas propostos pela expansão do universo de bens patrimoniais, englobando a arquitetura modernista? Neste trabalho, procuramos contribuir para essas reflexões e teorizações, conduzindo a um método que entendemos necessário antes da abordagem da obra de restauro. Embora convindo que as obras - como as de qualquer período ou tecnologia - tenham uma individualidade prioritária, há sempre uma base comum que deve ser considerada e a partir da qual evoluem os procedimentos do arquiteto. É para a formação/formatação dessa base comum que pretendemos contribuir com nossa experiência em duas obras importantes do acervo patrimonial do modernismo brasileiro. / You can trace back the theory of architecture restoration to Winckelmann: his \"Art History\", published in Dresden in 1764, presents a level of detail in the descriptions and even about the Greek and Roman construction processes, transcending the explicit concern with Art History. His thinking is that the remainings are the documents necessary to tell the evolution of architecture - in between the lines, stays the need for its preservation. However, Ruskin is accepted as the starter of the reflection and theorization. He practiced during his days a preservation without insurance criteria that in his understanding compromised the documentary and historical value of monuments: the ruins were preferable to those works, bringing an obvious and strong component of the current romanticism. In this sense, his thoughts were opposed to Violet-le-Duc who advocated for the theoretical proposal of the the stylistic restoration. Camillo Boito is who actually started the theory that, evolving, is the one accepted today: it formulates criteria and guidelines to think about the restoration process. His ideas are developed by G.Giovanoni, preparing the way for the letters of Athens and finally to Venice, even the restores \"spelling book\". These ideas that have their theoretical formulation more precise and developed in Cesare Brandi, in his \"Theory of Restoration.\" The rapid technological developments of the 20th century - as well as the entry of the Modernism works in the list of assets - made it necessary to extend the application of theoretical concepts to new technologies: - Which principles should guide the restorative interventions in Modern Architecture, when it is focused as cultural heritage? - What are the theoretical positions, which reflections must structure the thoughts before the technical procedures by the architect before the new problems posed by the expansion of the assets universe, encompassing the modernist architecture? In this paper, we try to contribute to these reflections and theories, leading to a method we have deemed necessary before the restoration work approach. While befitting that the works from any period or technology have a priority individuality, there is always a common basis that should be considered and from which the architect procedures evolve. It is for training / formatting of that common ground we want to contribute our experience in two important works of the net assets of Brazilian modernism.
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Introdução de espécies de sub-bosque em áreas de restauração de florestas estacionais semideciduais / Introduction of Understory species in Brazilian Seasonal Semidecidual Forests restoration areasMariana Meireles Pardi 07 February 2014 (has links)
Espécies típicas de sub-bosque são pouco estudadas quanto à sua aplicação na restauração e enriquecimento de florestas degradadas. São em geral arvoretas ou arbustos finais de sucessão, tolerantes ao sombreamento, capazes de germinar, se estabelecer e completar seu ciclo de vida neste ambiente, representando importante fonte de recursos como alimento e abrigo para polinizadores e dispersores. Porém, não são amplamente utilizadas nos plantios de restauração por não serem espécies de dossel, e em paisagens altamente fragmentadas há poucas chances de chegarem naturalmente em áreas em processo de restauração. Visando contribuir para o desenvolvimento de técnicas de plantio e enriquecimento em áreas degradadas ou em processo de restauração que favoreçam a recuperação do subbosque, este trabalho teve o objetivo de avaliar a sobrevivência e o crescimento de mudas de 10 espécies típicas de sub-bosque plantadas em quatro diferentes condições: plantio inicial de restauração, áreas em processo de restauração com 5 e 10 anos de idade e um fragmento remanescente degradado. Todas as áreas de estudo localizam-se na região de Batatais, SP e estão inseridas no Bioma Mata Atlântica, mais especificamente na fisionomia de Floresta Estacional Semidecidual. As mudas foram plantadas em janeiro de 2012 e observadas durante 15 meses quanto ao crescimento e sobrevivência. As áreas de estudo foram caracterizadas quanto aos atributos químicos, físicos e granulométricos do solo, cobertura e florística do dossel. A análise de componentes principais (PCA) mostrou que entre estas variáveis a que teve maior relação com o crescimento relativo das mudas foi a cobertura do dossel. A área que teve maior eficiência na introdução das espécies típicas de sub-bosque, considerando crescimento e sobrevivência, foi o plantio inicial de restauração, onde 3 espécies foram muito eficientes e 6 foram eficientes. No plantio com 5 anos 1 espécie foi muito eficiente e 4 foram eficientes, porém, cresceram bem menos que no plantio inicial. Os resultados apontaram ainda que apenas 3 espécies foram eficientes na área em processo de restauração de 10 anos e nenhuma no fragmento remanescente degradado, mostrando a dificuldade de se realizar o enriquecimento de áreas com alto nível de sombreamento, e de se reverter o processo de degradação nessas áreas, reforçando a importância da utilização de alta diversidade de espécies e grupos funcionais nos plantios de restauração e da conservação das áreas florestais remanescentes. / Species typical from understory layers are poorly studied regarding their use in restoration and enrichment of degraded forests. They are generally treelets or shrubs of final successional phase, shade tolerant, able to germinate, establish and complete their life cycle in this environment. They are an important source of resources as food and shelter to pollinators and dispersers. Despite their ecological importance, these plants have not been widely used in restoration plantings because they are not canopy species. In fragmented landscapes, these species have little chance of being recruited naturally into areas undergoing restoration. In order to contribute to the development of techniques of planting and enrichment in degraded areas or areas being restored and promote the recuperation of understory layers, this study evaluated the survival and growth of seedlings of 10 understory species planted under four different conditions: initial planting; 5-year-old restoration area; 10- year-old restoration area; and degraded forest fragment. All sites are located in the region of Batatais, SP, Brazil, inside the Atlantic Forest biome, specifically in the Seasonal Semidecidual Forest type. Seedlings were planted in January 2012 and measured during 15 months for their survival and growth. Study sites were characterized regarding soil chemical and physical attributes and granulometry, and canopy composition and coverage. Principal components analysis (PCA) showed that relative growth of seedlings was more strongly related to canopy coverage. Considering survivorship and growth, introduction of understory species was more successful at the initial planting site, where three species were very successful and six were successful. In the 5-year-old restoration area, one species was very successful and four were considered successful, however, they grew considerably less than at the initial planting site. Results point out that only three species were successful at the 10-year-old restoration area and none at the forest fragment, which shows the difficulty of enriching areas with high levels of shading, and thus, the difficulty of reversing degradation of forest remnants. This reinforces the importance of using high diversity of species and functional groups in restoration plantings and also of conserving remnant forests.
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Preservação e restauração cinematograficas no Brasil : a restauração do acervo de Hikoma Udhiara / Preservation and restoratio of Brazilian films : the restoration of Hikoma Udhiara's cinematograph materialsCesaro, Caio Julio 25 November 2007 (has links)
Orientador: Fernão Vitor Pessoa de Almeida Ramos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-11T21:56:42Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: A partir da pesquisa sobre o cenário atual da preservação e da restauração de filmes no Brasil, a tese apresenta conceitos que envolvem a área. Tomando a imagem em movimento como ponto de partida, estuda a composição da imagem analógica e da imagem digital, discutindo inclusive como o olho humano percebe a imagem, no que se refere à resolução da imagem e à natureza da imagem. Num momento que o digital apresenta-se como ¿melhor opção¿ para o fazer audiovisual, o texto apresenta uma perspectiva técnica e crítica da aplicação das tecnologias na preservação e na restauração cinematográficas, tratando a questão da ética na restauração digital e defendendo o digital como ferramenta de acesso aos conteúdos dos acervos de arquivos de imagem em movimento. Uma segunda parte da tese descreve o processo de restauração fotoquímica de parte do acervo cinematográfico de Hikoma Udihara, viabilizada por meio do PROMIC, mecanismo de incentivo à cultura do município de Londrina/PR. O texto detalha as circunstâncias que definiram a estratégia de restauração de filmes de Udihara. / Abstract: From the research on the current scene of the preservation and the restoration of films in Brazil, the thesis presents concepts that involve the area. Taking the image in movement as a beginning, the composition of the analogy and digital images are studied, also including the discussion about how human eye perceives the image, referring to the resolution of the image and its nature. In the moment that the digital appears as the ¿best option¿ for audiovisual making, the text presents a technical and critical perspective to its appliance in the cinematograph technology for preservation and restoration, discussing the ethics in digital restoration and taking defense of the digital like instrument of accessibility of contents in archives of moving images. A second part of the thesis describes the process of photochemical restoration of Hikoma Udihara¿s cinematograph materials, with money provided from Londrina City culture support program (PROMIC). The text gives details of the circumstances that had defined the strategy of restoration films in Udihara. / Doutorado / Doutor em Multimeios
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Nearshore restoration associated with large dam removal andI implications for ecosystem recovery and conservation of northeast Pacific fish: lessons learned from the Elwha dam removalShaffer, J. Anne 04 May 2017 (has links)
This dissertation addresses the relationship between large-scale dam removal and the nearshore ecosystem function for fish. The work is based on almost a decade’s worth of collaborative field work in the nearshore of the largest dam removal in the world recently completed on the Elwha River. The data analyzed span seven years prior to, during, and throughout the first year of each dam removal (January 2008 to November 2015). As of September 2015, approximately 2.6 million m3 of sediment material increased the area of the Elwha delta to over 150 ha. Long term study of fish in the estuary reveals fish community response to dam removal, and indicates likely interactions in the nearshore between hatchery and wild fish, including chum salmon critical to watershed recovery. Continued hatchery releases may therefore further challenge chum salmon recovery, and this interaction should be considered when planning for future watershed recovery. Community analysis revealed that, while species richness and taxonomic diversity do not appear to have a significant response to dam removal, functional diversity in the nearshore does respond significantly to dam removal. Three main shifts occurred in the nearshore: large scale and rapid creation of estuary habitats; delivery of large amounts of sediment to the delta/estuary in a short period of time, and; a shift in original habitats from tidally influenced to non-tidally influenced habitats resulted in changes in estuary function. Changes in functional diversity occur disproportionately in the new sites, which have more unstable, and so less resilient, communities. Functional diversity in the original estuary sites appears to be more resilient than in the newly created sites due to the large-scale environmental disruption that, ironically, created the new sites. However, the functional diversity at the original sites may be defined in part by management activities, including hatcheries that could mute/mask/inhibit other community responses. Further, functional diversity at the newly formed nearshore areas is predicted to stabilize as the habitats are vegetated and mature. Principal components analysis of Elwha fish community over the course of this study reveals that the fish communities of the Elwha are predictably grouped, indicating that while a few new species are observed, dam removal has not resulted in observable disruptions in fish community assemblages. And finally, nearshore habitats are critical for many forage fish species, and an emerging topic for large-scale dam removals. Forage fish spawning response to dam removal appears to be complex and may be related to multiple factors including high interannual variability in physical habitat conditions, geographic factors and complex life histories of forage fish. Habitat suitability for forage fish spawning should increase as restored ecosystem processes and newly created habitats mature and stabilize, indicating that time may be an important factor in nearshore restoration for forage fish spawning. It is therefore important to implement long-term monitoring and incorporate nearshore ecosystem process and function for multiple life history stages of nearshore species, including forage fish, into large-scale dam removal restoration and management planning. / Graduate / 2019-04-12
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Responses of brown trout and benthic invertebrates to catchment-scale disturbance and in-stream restoration measures in boreal river systemsLouhi, P. (Pauliina) 26 October 2010 (has links)
Abstract
Maintaining connectivity in boreal streams by rehabilitation procedures is a challenging task that requires ecological understanding based on empirical research. In this thesis, I examined the effects of stream rehabilitation on densities and growth of brown trout (Salmo trutta L.), as well as on benthic biodiversity. As streams are known to be closely connected to their watersheds, I also examined the effects of watershed drainage activities on stream organisms.
The results of this thesis have implications for enhancing salmonid populations, as well for maintaining stream biodiversity. First, regional climatic variability was shown to override local impacts of watershed management on stream biota. This highlights the importance of placing results from local studies in a regional context. Second, increased sedimentation that typically follows anthropogenic actions in the watershed did not only cause direct mortality on the early life stages of brown trout, but also forced them to emerge earlier from gravel and constrained their development. Thus, sedimentation may have far-reaching fitness consequences on juvenile salmonids.
Third, while instream rehabilitation did enhance habitat diversity for salmonid fish, there were only marginal effects on juvenile fish and benthic biodiversity. Therefore, the factors limiting stream biota, and obscuring positive effects of rehabilitation, are to be found elsewhere. For this purpose, my thesis offers at least three potential, not mutually exclusive explanations: (i) land use changes have altered watersheds and this can be seen as decreased stream biodiversity that cannot be corrected through local-scale restoration efforts; (ii) a habitat-forming organism group, stream bryophytes, is dispersal limited, slowing down any positive responses to restoration by fish or invertebrates that depend strongly on bryophytes; and (iii) changes to stream habitat heterogeneity caused by channelization for timber floating were rather modest to start with, and therefore any effects of stream habitat rehabilitation on stream biota are likely to be subtle.
Based on these findings, I suggest that future restoration efforts should be prioritized according to a comprehensive watershed assessment. Also, monitoring of projects should be more rigorous and preferably multidisciplinary, documenting the ecological as well as hydrological and socioeconomic outcomes of rehabilitation projects.
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Fire Effects and Management in Riparian Ecosystems of the Southwestern United States and MexicoWebb, Amanda D., Webb, Amanda D. January 2017 (has links)
Lowland riparian ecosystems constitute a tiny fraction of total land area in the southwestern United States and northern Mexico, yet they are extremely important to human livelihoods and biotic communities. Facing ongoing projected climate change toward hotter and drier conditions, riparian ecosystems are both vulnerable to changes in climate and increasingly critical to the well-being of humans and wildlife. Due to the dynamic nature of these ecosystems and their abundance of resources, riparian areas have been modified in various ways and to a large extent through human endeavor. These alterations often interfere with multiple and complex ecological processes, making riparian areas more vulnerable to disturbance and change. Few naturally functioning riparian areas remain, and those that do are imperiled by climate change, groundwater pumping, land use, and other factors. A small but growing body of literature suggests that wildfires may be increasing in frequency and severity in southwestern riparian zones. This literature review summarizes and synthesizes the state of the knowledge of wildfire and prescribed fire effects on abiotic processes and vegetation, and post-fire rehabilitation. Results suggest that in lowland riparian ecosystems, fire regimes and fire effects are influenced primarily by streamflow and groundwater regimes. Thus, increasing fire frequency and severity may be attributed to drought, land use, water use, and their subsequent effects on the spread of non-native plant species, as well as a history of fire suppression and increasing anthropogenic ignitions in areas with a growing human presence. Changing fire regimes are likely to have drastic and potentially irreversible effects on regional biodiversity and ecosystem function. However, there are options for managing riparian ecosystems that will be more resilient to fire and climate change, such as implementing environmental flows, prescribed fire, fuel reduction treatments, floodplain restoration, and promoting gene flow. This study is intended to inform management decisions, and identify gaps in systematically reviewed literature.
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