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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.
1

Hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas na Serra do Mar / Hydroseeding of native tree species to recover degraded areas on the Serra do mar

Basso, Fabiana de Arantes 19 June 2008 (has links)
A técnica da hidrossemeadura é comumente empregada como medida de recuperação de taludes gerados nos empreendimentos rodoviários, áreas degradadas pela mineração, aeroportos e hidrelétricas, utilizando gramíneas agressivas e leguminosas visando um rápido recobrimento do solo para conter a erosão. O uso de espécies arbustivo-arbóreas nativas na hidrossemeadura ainda é pouco estudado, destacando-se alguns trabalhos de desenvolvimento de equipamentos e escolha de espécies adequadas. Inserido neste contexto a proposta do trabalho foi testar a viabilidade da técnica da hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas inseridas em uma matriz ainda com grande cobertura florestal remanescente, possibilitando o uso de uma baixa diversidade de espécies na hidrossemeadura, uma vez que o enriquecimento ocorreria naturalmente, com propágulos oriundos do entorno, se a condição do ambiente permitir a fixação desses propágulos. Para isto foram aplicados 14,88 kg de sementes em 2,64 ha de área, sendo 2,976 kg de cada uma das seguintes espécies arbustivo-arbóreas: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius e Senna multijuga. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 2x5 com um tratamento adicional e com quatro repetições de cada bloco. Foram testadas cinco doses diferentes de sementes (Kg/ ha) e a influência do adubo químico (NPK) no momento da aplicação da hidrossemeadura no preenchimento da área. A dissertação foi dividida em dois capítulos, o primeiro referente à viabilidade da técnica da hidrossemeadura, tendo o segundo avaliado o sucesso de estabelecimento das espécies utilizadas. De maneira geral a técnica da hidrossemeadura apresentou-se viável para preenchimento das áreas, porém, estudos com espécies arbustivo-arbóreas são necessários para indicação das espécies mais adequadas. / Hydroseeding is a common practice on the restoration of slopes generated by road, airport and hydroelectric constructions or mining activities, and its usually applied with fast-growing grasses and legumes, aiming rapid soil recovery and erosion control. Hydroseeding of native tree species is scarce, except for few studies on equipment development and selection of adequate species. Within this context, this study aims to test the feasibility of native tree species on hydroseeding as a technique to recover degraded areas within a landscape where prevails forest remnants, which allows a low diversity on hydroseeding, once the enrichment of species may occur naturally through incoming propagules from forested neighbourhood. The native tree species evaluated by this study were: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius and Senna multijuga. Five different quantities of seeds (Kg/ ha) and the influence of chemical manure (NPK) during application were tested. It was a 2x5 factorial experiment folowing the randomized block design and with an additional control treatment (without hydroseeding nor chemical manure). Dissertation is presented on two chapters: the first one refers to the native tree species´ hydroseeding feasibility and the second evaluates the establishment success of these species. As an overall conclusion hydroseeding is feasible and effective to recover degraded areas, although further studies are needed to indicate the most suitable native tree species for this technique.
2

Specialty Coffee in Costa Rica: Effect of Environmental Factors and Management Options on Soil Chemistry and Microbial Composition

Sturm-Flores, Linda 2012 May 1900 (has links)
In the Central Valley of Costa Rica in the Department of Heredia, I investigated the soil chemical properties and microbial communities under four native shade tree species in a coffee agroforestry system. In the second year of the study, Effective Microorganisms, a microbial inoculant, was applied to examine its effect on soil chemistry. The shade tree species included in this study were Anonna muricata L., Diphysa americana Mill., Persea americana Mill., and Quercus spp. L. Plots measured 20 by 30 meters and were replicated three times for each shade tree species except for Quercus spp., which only had two replications. Twelve composite soil samples were collected from each plot in 2008 and again in 2009, and twelve composite foliar samples were taken from the coffee plants in each plot in 2008. The results of this study indicated that the species of native shade tree had a significant effect on soil ammonium-N, nitrate-N, total dissolved nitrogen and magnesium. Sun or shade position had a significant effect on dissolved organic nitrogen and dissolved organic carbon. The species of native shade tree also had a significant effect on the composition of soil microbial communities. PLFA analysis revealed a significant difference in soil fungi abundance in soil samples from Annona plots relative to those from Persea plots. Effective microorganisms in combination with the tree species, as well as in combination with species and sun or shade position, had a significant interaction effect on soil ammonium-N, with the EM-treated plots showing higher concentrations of soil ammonium-N. There was a significant positive correlation between soil pH and foliar calcium, as well as soil dissolved organic nitrogen and foliar %N, at p< 0.01. This study suggests that Quercus spp. is a tree species that may help to regulate the cycling of nitrogen in the coffee agroecosystem. Annona muricata appears to inhibit the action of some fungal species and may reduce the occurrence of fungal pathogens in the soil, although the present study did not explore this issue. Although Diphysa americana is a legume, it does not appear to increase the amount of soil nitrogen in the vicinity of the coffee plants themselves. All four tree species in this study improve coffee soils by increasing soil concentrations of dissolved organic nitrogen and dissolved organic carbon. Coffee yield data and long term observations on the health of the coffee plants would clarify whether one of these species is particularly beneficial, from an agronomic perspective, for the productivity of this coffee agroecosystem.
3

Hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas na Serra do Mar / Hydroseeding of native tree species to recover degraded areas on the Serra do mar

Fabiana de Arantes Basso 19 June 2008 (has links)
A técnica da hidrossemeadura é comumente empregada como medida de recuperação de taludes gerados nos empreendimentos rodoviários, áreas degradadas pela mineração, aeroportos e hidrelétricas, utilizando gramíneas agressivas e leguminosas visando um rápido recobrimento do solo para conter a erosão. O uso de espécies arbustivo-arbóreas nativas na hidrossemeadura ainda é pouco estudado, destacando-se alguns trabalhos de desenvolvimento de equipamentos e escolha de espécies adequadas. Inserido neste contexto a proposta do trabalho foi testar a viabilidade da técnica da hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas inseridas em uma matriz ainda com grande cobertura florestal remanescente, possibilitando o uso de uma baixa diversidade de espécies na hidrossemeadura, uma vez que o enriquecimento ocorreria naturalmente, com propágulos oriundos do entorno, se a condição do ambiente permitir a fixação desses propágulos. Para isto foram aplicados 14,88 kg de sementes em 2,64 ha de área, sendo 2,976 kg de cada uma das seguintes espécies arbustivo-arbóreas: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius e Senna multijuga. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 2x5 com um tratamento adicional e com quatro repetições de cada bloco. Foram testadas cinco doses diferentes de sementes (Kg/ ha) e a influência do adubo químico (NPK) no momento da aplicação da hidrossemeadura no preenchimento da área. A dissertação foi dividida em dois capítulos, o primeiro referente à viabilidade da técnica da hidrossemeadura, tendo o segundo avaliado o sucesso de estabelecimento das espécies utilizadas. De maneira geral a técnica da hidrossemeadura apresentou-se viável para preenchimento das áreas, porém, estudos com espécies arbustivo-arbóreas são necessários para indicação das espécies mais adequadas. / Hydroseeding is a common practice on the restoration of slopes generated by road, airport and hydroelectric constructions or mining activities, and its usually applied with fast-growing grasses and legumes, aiming rapid soil recovery and erosion control. Hydroseeding of native tree species is scarce, except for few studies on equipment development and selection of adequate species. Within this context, this study aims to test the feasibility of native tree species on hydroseeding as a technique to recover degraded areas within a landscape where prevails forest remnants, which allows a low diversity on hydroseeding, once the enrichment of species may occur naturally through incoming propagules from forested neighbourhood. The native tree species evaluated by this study were: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius and Senna multijuga. Five different quantities of seeds (Kg/ ha) and the influence of chemical manure (NPK) during application were tested. It was a 2x5 factorial experiment folowing the randomized block design and with an additional control treatment (without hydroseeding nor chemical manure). Dissertation is presented on two chapters: the first one refers to the native tree species´ hydroseeding feasibility and the second evaluates the establishment success of these species. As an overall conclusion hydroseeding is feasible and effective to recover degraded areas, although further studies are needed to indicate the most suitable native tree species for this technique.
4

CRESCIMENTO E TOLERÂNCIA DE Senna multijuga E Erythrina crista-galli COM A UTILIZAÇÃO DE TURFA EM SOLO CONTAMINADO COM ZINCO / GROWTH AND TOLERANCE OF Senna multijuga AND Erythrina crista-galli WITH THE UTILIZATION OF PEAT IN SOIL CONTAMINATED WITH ZINC

Scheid, Douglas Leandro 18 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The amount of areas contaminated with heavy metals is constantly increasing. Zinc is a micronutrient and also a contaminant when found in larger quantities. Contaminated areas require recovery, and one of the techniques is the use of plant species, but studies are needed to identify suitable species. The objective of this study was to evaluate the initial development and tolerance Senna multijuga and Erythrina crista-galli the soil contaminated with zinc and use of peat. Thus it was conducted three experiments. The first studied the growth, tolerance and copper accumulation in seedlings of Senna multijuga and Erythrina crista-galli. In the second study evaluated the effect of peat (200 ml of peat kg-1 in soil) and the growth and tolerance Senna multijuga in soil contaminated with zinc. In the third, we evaluated the use of Erythrina crista-galli L. and peat zinc contaminated soil phytoremediation. In the first study, E. crista-galli and S. multijuga decreased in morphological parameters with increasing doses, while the zinc concentration in the aerial part and root increased with doses in both species. Both species have low translocation of zinc and were sensitive soil contamination with zinc. The species is capable of phytostabilization of zinc. With the use of peat, zinc levels in the shoot and roots are smaller and soil contaminated with zinc tolerance of Senna multijuga seedlings is higher. In Erythrina crista-galli translocation of Zn is greater with the use of the peat, but still shows moderate tolerance to Zn. The use of peat does not allow the species to be considered phytoextractor of Zn. / A quantidade de áreas contaminadas com metais pesados aumenta constantemente. O zinco é um micronutriente e também um contaminante, quando encontrado em grandes quantidades. As áreas contaminadas necessitam de recuperação, e uma das técnicas é o emprego de espécies vegetais, porém são necessários estudos que identifiquem as espécies aptas. Assim, o objetivo deste trabalho foi avaliar o crescimento inicial e a tolerância de Senna multijuga e Erythrina crista-galli a solo contaminado com zinco e com utilização de turfa. Desse modo foram realizados três experimentos. O primeiro estudou o crescimento, tolerância e acúmulo de cobre em mudas de Senna multijuga e Erythrina crista-galli. No segundo trabalho avaliou-se o efeito da turfa (200 mL de turfa kg-1 de solo) e no crescimento e tolerância de Senna multijuga em solo contaminado com zinco. No terceiro, avaliou-se a utilização de Erythrina cristagalli L. e turfa para fitorremediação de solo contaminado com zinco. No primeiro trabalho, a E. crista-galli e a S. multijuga apresentaram redução nos parâmetros morfológicos com o aumento das doses, enquanto que os teores de zinco na parte aérea e radicular aumentaram com as doses em ambas as espécies. Ambas as espécies apresentaram baixa translocação de zinco e foram sensíveis a contaminação do solo com zinco. As espécies estudadas tem capacidade de fitoestabilizar o zinco. Com a utilização de turfa, os teores de zinco na parte aérea e radicular são menores e a tolerância a solo contaminado com zinco das mudas de Senna multijuga é maior. Na Erythrina crista-galli a translocação de Zn é maior com o uso de trufa, porém mesmo assim apresenta tolerância moderada ao Zn. A utilização de turfa não permite que a E. crista-galli acumule Zn para ser considerada espécie fitoextratora do metal.
5

<b>Native Woody Diversity, Composition and Tree Growth Responses to Invasive Plant Treatment in Non-Industrial Private Forests</b>

Gabriela Marie Krochmal (19175110) 19 July 2024 (has links)
<p dir="ltr">To reduce the establishment and spread of invasive plant species, the Environmental Quality Incentive Program (EQIP) was created in 1996 to provide financial and technical assistance to private landowners to aid in conservation practices and address environmental concerns. From 2014-2022, approximately $90 million dollars was obligated to the EQIP for completed contracts of over 240,000 hectares in Indiana. However, to date, there has been no examination of whether participation in conversation cost sharing programs has resulted in the recovery of native tree diversity, growth, and reproduction following the treatment of invasive plants. Furthermore, there is a gap in our understanding of the effectiveness of EQIP and its success in achieving and maintaining management goals. This thesis quantifies the composition, diversity, regeneration density and growth of tree species in response to invasive plant treatments at sites that participated in the EQIP. In particular, I investigated how the species composition of woody seedlings (stems < 2 cm dbh) and woody saplings (2 – 5 cm dbh) differed across EQIP-treated and untreated reference plots. I then examined how native species richness and diversity values differed between EQIP-treated and untreated plots. Lastly, I used dendroecological methods to determine how treatment of invasive shrubs affected overstory tree growth. Across the state, I found that native species richness of seedlings and saplings was greater in EQIP-treated plots then within reference plots. Reference plots were associated with invasive species such as <i>Lonicera maackii</i> (Amur honeysuckle), <i>Rosa multiflora</i> (multiflora rose), <i>Elaeagnus umbellata</i> (autumn olive) and <i>L. japonica</i> (Japanese honeysuckle), while EQIP-treated plots were associated with native tree species, such as <i>Carya ovata</i> (shagbark hickory),<i> Ulmus americana </i>(American elm), <i>Fraxinus americana</i> (white ash), <i>Liriodendron tulipifera</i> (yellow-poplar), <i>Quercus alba</i> (white oak), <i>Q. velutina</i> (black oak), and shrubs, such as <i>Rubus allegheniensis</i> (Allegheny blackberry) and <i>Lindera benzoin</i> (spicebush). I observed that trees generally had greater basal area increment growth following invasive shrub treatments; therefore, the reduction of invasive shrub dominance on EQIP-enrolled lands has led to a small, but significant, increase in overstory tree growth. I observed high within-group variability in growth for EQIP-treated and reference plots, likely due to differing management strategies across privately owned forests. Overall, my results demonstrate that participation in the EQIP has positively benefited species richness, and native species composition, and tree growth.</p>

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