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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.
801

Porovnání rekultivovaných a sukcesních ploch z pohledu rostlinné diverzity na vybraných hydrosystémech Třeboňské pánve Suchdolské pískovny. / The comparison of restorated and successional areas from the point of view ofthe plant diversity - Suchdol sandpit lakes, Třeboň Basin Area

ZAORALOVÁ, Petra January 2014 (has links)
The Diploma´s thesis deals with the issue of comparison of recultivated areas and areas in the point of ecological succession from the viewpoint of the plant diversity of chosen hydro-ecosystems of Trebon basin, in the area of Suchdol nad Lužnicí. Mapped sandpits Cep, Cep I, Tušť a Františkov are situated in the flood plain of the river Lužnice. Local mining of sandy gravel started in 1950s and in some areas it has not finished until now. Every mining process leads to extensive damages of the landscape, which should be corrected. The aim of this thesis is to map and compare the areas on the coast of extracted sandpits where the recultivation was done with those which were left to "controlled" ecological succession.
802

Dynamic coastal dune restoration and spatial-temporal monitoring at the Wickaninnish Dunes, Pacific Rim National Park Reserve, British Columbia, Canada

Darke, Ian 02 January 2019 (has links)
This dissertation presents the results of a multi-year interdisciplinary study of a dynamic coastal dune ecosystem restoration effort in Pacific Rim National Park Reserve in British Columbia, Canada. The research is the result of a collaboration with Parks Canada Agency (PCA) who, under the Species at Risk Act (SARA), are mandated to restore habitat for SARA listed species within the dune complex. In response, PCA committed to, and implemented, a dynamic dune ecosystem restoration program that involved widespread removal of invasive vegetation (Ammophila spp.), transplanting of native vegetation, introduction of an endangered species, and volunteer programs to prevent re-growth of Ammophila. A comprehensive monitoring program was developed with PCA and undertaken by the author and PCA collaborators from start of the project in Summer 2008 to Fall of 2012. This dissertation is the product of independent research by the author carried out under the supervision of the advisory committee and does not reproduce written materials prepared for, or by, PCA. The dissertation consists of three separate journal manuscripts (the first two published by completion of the dissertation) that stand alone as independent investigations but are structured here to provide a natural progression of research findings and allow for an overall synthesis of ideas and broader contributions of the research. The dune restoration program afforded an opportunity to review restoration trends and methods and implement a strategy and monitoring protocols based on leading edge science. Accordingly, the first manuscript, Chapter 2, summarises recent trends in coastal dune restoration, discusses relevant research surrounding beach-dune morphodynamics and coastal dune activity, and reviews preliminary data from the project. The study identifies usable control data for the project and builds the criteria for assessing the project as a whole. The second manuscript, Chapter 3, presents and analyses the core data obtained for the dissertation - 5 years of geomorphic monitoring from detailed land surveys with 3 years of analysis of beach-foredune-transgressive dune sediment budget responses derived from aerial LiDAR surveys. This chapter identifies several trends in the dune systems’ response to restoration that, with reference to the indicators developed in Chapter 2, suggest improved levels of dynamism in the landscape. Finally, Chapter 4 (manuscript 3), extends the findings of the restoration study and utilises the rich data set obtained from the restoration program to develop a dynamic mapping technique that better conveys the spatial-temporal morphodynamic behaviour of dune ecosystems. The study comments broadly on the potential to apply these data and techniques to the study of disturbance events in beach-dune systems. The dissertation is concluded (Chapter 5) with an overall summary of key research objectives and contributions, and presents recommendations for future research. / Graduate
803

Chuva e banco de sementes do solo em diferentes sistemas de restauração ecológica da floresta estacional semidecidual / Seed rain and soil seed bank in different restoration systems of the seasonal semideciduous tropical forest

Villota Cerón, Diana Elizabeth [UNESP] 11 September 2015 (has links) (PDF)
Made available in DSpace on 2016-03-07T19:20:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-09-11. Added 1 bitstream(s) on 2016-03-07T19:24:22Z : No. of bitstreams: 1 000858850.pdf: 4113198 bytes, checksum: 7a229197c9cf848ced52da67c1163244 (MD5) / A avaliação da regeneração natural dos ecossistemas é importante porque permite entender a sucessão natural e determina se os esforços para recuperar a estabilidade e integridade biológica estão-sendo efetivos. Na regeneração natural dos ecossistemas, a disponibilidade de sementes é um fator importante para a sobrevivência e persistência da comunidade vegetal dentro do hábitat. Assim, o banco e a chuva de sementes têm sido considerados como os principais processos para a manutenção das comunidades vegetais. O objetivo do presente estudo foi avaliar a importância da dispersão e persistência de sementes no banco do solo na dinâmica de regeneração da comunidade vegetal em diferentes sistemas de restauração da floresta estacional semidecidual. O estudo foi realizado em duas áreas experimentais de Botucatu (São Paulo), cada uma contendo características diferentes de solo. Em cada área, há 18 anos, foram implantados cinco sistemas de restauração sob um delineamento em blocos com três repetições, e parcelas de 50 x 50 m, sendo: a) semeadura direta (SEMD), b) sistema agroflorestal (SAF), c) consórcio de espécies para madeira e lenha (COML), e) plantio diversificado (PDIV) e f) restauração passiva (controle) (RPSV). Além disso, foi avaliado um fragmento de floresta natural (FRAG) nas duas áreas como ecossistema de referência. Para o estudo da chuva de sementes, foram instalados, em cada parcela, ... / The assessment of natural regeneration is important to understanding the successional trajectory of restored ecosystems and determining if the efforts to restore the stability and biological integrity are being effective. Seed availability is an important factor for the survival and persistence of plant community within the habitat. Thereby, seeds bank and seeds rain have been considered as the principal processes for plant communities maintenance. The aim of this study was to evaluate the role of the soil seed bank and the seed rain for the regeneration dynamics of plant communities under different seasonal semi-deciduous forest restoration systems. The study was undertaken in two experimental sites at Botucatu county (São Paulo), each one havind contrasting soil characteristics. Five restoration systems were stablished in 1997-1998, in a random block design with three replications in each site, with 50 x 50 m plots. Treatments were: a) direct seeding (SEMD), b) agroforestry system (SAF), c) timber and firewood mixed species plantation(COML), e) high-diversity plantation (PDIV) and f) passive restoration as control (RPSV). Furthermore, a natural forest fragment (FRAG) was evaluated in each area as a reference ecosystem. Soil samples were collected at 5 cm deepth (8 samples perplots), in order to analyse the seed bank by the germination method, respectively during the rainy and dry seasons. Soil samples were installed in germination boxes at the nursery. Sedling emergence was monitored during six months. For the seed rain study, 4 circular traps of 0.25 m² were installed in each plot, and the seeds were collected monthly during one year. The seed bank was composed mainly by herbaceous species in all restoration systems, comprinsing 83% and 73% of species for areas 1 and 2 respectively. The seed bank average density was 632.29 and 794.61 seeds / m², for areas 1 and 2, respectively. The highest dens ...
804

Kanalisering och restaurering av vattendrag påverkar mossamhällen i strandzonen : -En studie av Vindelälvens biflöden / Channelization and restoration affects bryophyte communities in the riparian zone : - A study of tributaries to Vindelälven

Aalto, Anders January 2018 (has links)
This study compared three different types of reaches at streams and how bryophyte species richness, diversity and abundance in the riparian zone differ between them. The different types of reaches are those that have been treated by two types of restoration techniques (best practise and advanced) and streams that have still not been restored (channelized). The bryophytes were gathered from 15 tributaries to Vindelälven, which is in northern Sweden. Bryophyte species richness and diversity was highest at the streams that were still not restored, and I found numerous factors that could explain why this was the case. Fourteen environmental variables were tested against the three bryophyte factors to try to explain the variation found in the study. Time since restoration and the amount of tree biomass in the area could explain the species richness found at the different river types. The study shows that short-term effects of restoration on the riparian zone is a decrease in bryophyte species richness and diversity. However, given enough time the bryophytes are expected to recover in regards to species richness and diversity.
805

Regeneração natural de um fragmento de cerrado degradado com a formação de pastagens de braquiária (Urochloa decumbens (Stapf) R. D. Webster)

Rissi, Mariana Ninno [UNESP] 29 April 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-29Bitstream added on 2014-06-13T20:16:46Z : No. of bitstreams: 1 rissi_mn_me_botib.pdf: 4013269 bytes, checksum: 7f2b7759ec50422f03c785156a434e65 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The concepts degraded environment and disturbed environment were initially proposed based on the observation of such processes in forest fragments. Disturbed environments, when subjected to agents, can reestablish after the removal of the disturbing factor. However, when the action is more intense and there is no potential to return to conditions similar to the previous ones, the vegetation is considered degraded. The question is: Would the actions that make a forest degraded have the same consequence in cerrado fragments? The present study aims to analyze the composition of the regenerative community over one year in a cerrado fragment located in the Municipal Botanical Garden of Bauru City, São Paulo State, Brazil (JBMB); to provide data to understand the ecological processes involved in the natural regeneration of degraded cerrado areas and the chemical combat as a viable alternative or not to control alien plants; and to contribute to the knowledge of the cerrado flora in Bauru region. Thus, some questions were raised. How does natural regeneration of the woody vegetation of a degraded cerrado occur? Would the chemical combat against invasive alien plants change the development of cerrado plants? Is intervention in the control of those plants favorable? The study area was deforested by the action of settlers, who established there in 1997. In 2007 the area was endorsed to the Municipal Botanical Garden of Bauru City (JBMB). During this period, the native vegetation was substituted for pasture. By two years ago the place has been abandoned and the natural vegetation started to regenerate. To evaluate the natural regeneration potential of cerrado, a comparative floristic and phytosociological survey was carried out in three areas inside JBMB. The first area is inserted in a cerradão fragment, free of... (Complete abstract click electronic access below)
806

Sistemas agroflorestais na recuperação de áreas de preservação permanente / Agroforestry systems in the restoration of permanent preservation areas

Machado, Fábio José 10 August 2012 (has links)
Made available in DSpace on 2016-06-02T18:57:41Z (GMT). No. of bitstreams: 1 4625.pdf: 3974872 bytes, checksum: b2b4e12ae73ff0b605e62f2fd14fd23b (MD5) Previous issue date: 2012-08-10 / This essay aims at evaluating the use of alternative reforestation models in order to recover degraded areas in permanent preservation areas. The potential of effective recovery was analyzed regarding sustainability indicators which were applied according to the principles of the MESMIS tool. Comparing a forest fragment (AT), a handled agroforestry system (SAF), two recovery areas and a pasture area. All of the analyzed places belong to strategic regions considering the biodiversity conservation as well as water resources, as they are located in different environmentally protected zones (APA s), which provide water for the Cantareira System (Sistema Cantareira). The analysis took place in the recommended period for the monitor in the RAD projects, in the first three years in order to evaluate the current situation and also intervene in the maintenance if necessary. The sustainability indicators choice was based on the easy applicability and facts interpretation, which belongs to three groups: man-induced disturbance, composition and ecological function. The maninduced disturbance revealed that there was evidence of disturbance in all the places. In the composition indicators, the forestry fragment (AT) showed the higher value considering the biodiversity index. However the difference was not really significant if compared to the handled SAF. In the implementation of ecological function indicators, the SAF showed the highest rate of tree canopy. So, it was determined that the agroforestry system shows good results considering the diversity when it is handled. In addition to that, it showed big viii potential in recovering degraded areas and in enrichment of forest fragments that can be handled for a longer period than the one estimated by law. / O presente trabalho teve como objetivo promover uma avaliação da utilização de modelos alternativos aos modelos convencionais de reflorestamento para a recuperação de áreas degradadas (AD) em áreas de preservação permanente (APP). Foram analisados o potencial efetivo de recuperação em APP por meio do uso de indicadores de sustentabilidade aplicados de acordo com os princípios da ferramenta MESMIS. Foram comparados um fragmento florestal (AT), um sistema agroflorestal manejado (SAF), duas áreas em recuperação (RAD) e uma área de pastagem. Todas as áreas analisadas pertencem a regiões estratégicas tanto para a conservação da biodiversidade como de recursos hídricos, pois estão em diferentes Áreas de Proteção Ambiental (APA s), as quais são fornecedoras de água para o Sistema Cantareira. A análise ocorreu dentro do período recomendado para o monitoramento de projetos de RAD, ou seja, em seus anos iniciais (até 3 anos) para se avaliar a situação atual e intervir na manutenção quando houver necessidade. A escolha dos indicadores de sustentabilidade foi baseada na fácil aplicabilidade e interpretação dos dados, pertencentes a três grupos: perturbações antrópicas, composição e função ecológica. Os indicadores de perturbações antrópicas mostraram que em todas as áreas havia indícios de perturbação. Nos indicadores de composição, o fragmento florestal (AT) apresentou o maior valor para o índice de diversidade, embora sem diferenças significativas em comparação com o SAF manejado. Na aplicação dos indicadores de função ecológica, o SAF apresentou a maior taxa de cobertura de copa. Assim, podevi se constatar que o sistema agroflorestal quando manejado apresenta bons resultados quanto à diversidade, e grande potencial para a recuperação de áreas degradadas e para enriquecimento de fragmentos florestais, podendo ser manejado por um período maior do que prevê a atual legislação.
807

Método avaliativo e qualitativo de parques lineares da cidade de São Paulo, (SP) / Evaluation and qualitative method of linear parks of the city of São Paulo, (SP)

Biagolini, Carlos Humberto 16 March 2018 (has links)
Submitted by Carlos Humberto Biagolini (professorcarlosciencias@zipmail.com.br) on 2018-04-21T00:24:14Z No. of bitstreams: 1 Método avaliativo e qualitativo de parques lineares da cidade de São Paulo, (SP).pdf: 5058241 bytes, checksum: eb72f992878a44965256105f4ca22e71 (MD5) / Approved for entry into archive by Lucimara Kurokawa Shinoda null (lucimaraks@sorocaba.unesp.br) on 2018-04-23T20:25:32Z (GMT) No. of bitstreams: 1 biagolini_ch_dr_soro.pdf: 5058241 bytes, checksum: eb72f992878a44965256105f4ca22e71 (MD5) / Made available in DSpace on 2018-04-23T20:25:32Z (GMT). No. of bitstreams: 1 biagolini_ch_dr_soro.pdf: 5058241 bytes, checksum: eb72f992878a44965256105f4ca22e71 (MD5) Previous issue date: 2018-03-16 / Parques lineares são áreas estruturadas às margens de córregos e rios que apresentam a importante finalidade de revitalizar áreas degradadas, preservar áreas de várzea responsáveis pela absorção de água pluvial e, ainda, criar espaços de lazer e socialização. O objetivo deste trabalho foi o de desenvolver uma metodologia capaz de avaliar de forma quali-quantitativa 10 parques lineares entre os 24 parques existentes na cidade de São Paulo, além de identificar os principais elementos da avifauna e flora. Os parques lineares escolhidos foram: Aricanduva, Canivete, do Fogo, Gamelinha, Ipiranguinha, Itaim, Parelheiros, Rapadura, Sapé e Tiquatira. Com relação aos resultados, o parque lineare Itaim foi classificado apenas como regular enquanto que os parques lineares Aricanduva, Canivete, do Fogo, Gamelinha, Ipiranguinha, Parelheiros, Rapadura e Sapé foram classificados como bons e somente o parque linear Tiquatira foi classificado como excelente pela metodologia proposta neste trabalho. Quanto à avifauna e flora, foram identificadas 23 espécies de aves e 151 espécies vegetais. A utilização deste sistema de avaliação de parques lineares pode ser de grande importância para a avaliação destes espaços, dado que por meio desta é possível apontar as áreas que necessitam de intervenções e ações imediatas a fim de equalizar a qualidade destes espaços, melhorando seus serviços prestados ao meio ambiente e consequentemente para a qualidade de vida da população usuária. / Linear parks are structured areas along the banks of streams and rivers that have the important purpose of revitalizing degraded areas, preserving floodplain areas responsible for the absorption of rainwater, and creating leisure and socialization spaces. The objective of this work was to develop a methodology capable of qualitatively and quantitatively evaluating 10 linear parks among the 24 existing parks in the city of São Paulo, in addition to identifying the main elements of the flora and fauna. The linear parks chosen were: Aricanduva, Canivete, Fogo, Gamelinha, Ipiranguinha, Itaim, Parelheiros, Rapadura, Sapé and Tiquatira. Regarding the results, the Itaim linear park were classified as regular, while the Aricanduva, Canivete, do Fogo, Gamelinha, Ipiranguinha, Parelheiros, Rapadura e Sapé linear parks were classified as good and only Tiquatira linear park was classified as excellent by methodology proposed in this work. Regarding fauna and flora, 151 plant species and 23 bird species were identified. The use of this system of evaluation of linear parks can be of great importance, since it is possible to point out the areas that need interventions and immediate actions in order to equalize the quality of these spaces, improving their services rendered and consequently the quality of life of the user population.
808

Chuva e banco de sementes do solo em diferentes sistemas de restauração ecológica da floresta estacional semidecidual /

Villota Cerón, Diana Elizabeth, 1987. January 2015 (has links)
Orientador: Vera Lex Engel / Banca: Giselda Durigan / Banca: José Marcelo Domingues Torezan / Resumo: A avaliação da regeneração natural dos ecossistemas é importante porque permite entender a sucessão natural e determina se os esforços para recuperar a estabilidade e integridade biológica estão-sendo efetivos. Na regeneração natural dos ecossistemas, a disponibilidade de sementes é um fator importante para a sobrevivência e persistência da comunidade vegetal dentro do hábitat. Assim, o banco e a chuva de sementes têm sido considerados como os principais processos para a manutenção das comunidades vegetais. O objetivo do presente estudo foi avaliar a importância da dispersão e persistência de sementes no banco do solo na dinâmica de regeneração da comunidade vegetal em diferentes sistemas de restauração da floresta estacional semidecidual. O estudo foi realizado em duas áreas experimentais de Botucatu (São Paulo), cada uma contendo características diferentes de solo. Em cada área, há 18 anos, foram implantados cinco sistemas de restauração sob um delineamento em blocos com três repetições, e parcelas de 50 x 50 m, sendo: a) semeadura direta (SEMD), b) sistema agroflorestal (SAF), c) consórcio de espécies para madeira e lenha (COML), e) plantio diversificado (PDIV) e f) restauração passiva (controle) (RPSV). Além disso, foi avaliado um fragmento de floresta natural (FRAG) nas duas áreas como ecossistema de referência. Para o estudo da chuva de sementes, foram instalados, em cada parcela, ... / Abstract: The assessment of natural regeneration is important to understanding the successional trajectory of restored ecosystems and determining if the efforts to restore the stability and biological integrity are being effective. Seed availability is an important factor for the survival and persistence of plant community within the habitat. Thereby, seeds bank and seeds rain have been considered as the principal processes for plant communities maintenance. The aim of this study was to evaluate the role of the soil seed bank and the seed rain for the regeneration dynamics of plant communities under different seasonal semi-deciduous forest restoration systems. The study was undertaken in two experimental sites at Botucatu county (São Paulo), each one havind contrasting soil characteristics. Five restoration systems were stablished in 1997-1998, in a random block design with three replications in each site, with 50 x 50 m plots. Treatments were: a) direct seeding (SEMD), b) agroforestry system (SAF), c) timber and firewood mixed species plantation(COML), e) high-diversity plantation (PDIV) and f) passive restoration as control (RPSV). Furthermore, a natural forest fragment (FRAG) was evaluated in each area as a reference ecosystem. Soil samples were collected at 5 cm deepth (8 samples perplots), in order to analyse the seed bank by the germination method, respectively during the rainy and dry seasons. Soil samples were installed in germination boxes at the nursery. Sedling emergence was monitored during six months. For the seed rain study, 4 circular traps of 0.25 m² were installed in each plot, and the seeds were collected monthly during one year. The seed bank was composed mainly by herbaceous species in all restoration systems, comprinsing 83% and 73% of species for areas 1 and 2 respectively. The seed bank average density was 632.29 and 794.61 seeds / m², for areas 1 and 2, respectively. The highest dens ... / Mestre
809

Avaliação clínica longitudinal de restaurações de uma resina composta bulk-fill em dentes posteriores / Longitudinal clinical evaluation of restorations of a bulk-fill composite on posterior teeth

Rodrigues, Roger Borges January 2016 (has links)
Objetivos: O objetivo deste ensaio clínico randomizado foi avaliar o comportamento de restaurações de resina composta bulk-fill em dentes posteriores (classes I e II). Metodologia: Dezessete pacientes que necessitavam de restaurações em pelo menos dois dentes posteriores foram selecionados para participar do estudo. As causas para indicação das restaurações foram: substituição de restauração deficiente de amálgama ou resina composta e/ou lesão de cárie. Em cada paciente foram realizadas duas restaurações. Randomicamente, uma cavidade foi restaurada com a resina nanohíbrida Esthet-X HD (grupo controle) e a outra restaurada com a resina Esthet-X HD associada à resina de baixa contração Surefil SDR Flow (grupo teste). Em ambos os grupos, um sistema adesivo convencional de dois passos (XP Bond) foi utilizado. Todos os pacientes receberam tratamento global para a atividade cariosa. Após um período de quatro anos, a qualidade das restaurações foi avaliada por 1 examinador previamente calibrado, através de uma modificação do método USPHS e através do método FDI. Os dados obtidos foram submetidos à análise estatística pelo teste não-paramétrico Mann-Whitney (p<0,05) e a concordância intra-observador avaliada através de teste Kappa. Resultados: No quarto ano de acompanhamento, 26 dentes (18 restaurações classe I e 8 classe II) foram avaliadas, e não foram observadas diferenças estatisticamente significantes entre as restaurações dos grupos controle e teste para os métodos de avaliação utilizados. Não houve falhas em nenhuma das restaurações ao longo do tempo. Conclusão: A qualidade das restaurações classe I e II com resina bulk-fill foi semelhante à das restaurações com resina nanohíbrida convencional. A técnica com resina bulk-fill mostrou bom desempenho clínico tão bom quanto a convencional durante os 4 anos de acompanhamento. / Objectives: The objective of this randomized clinical trial was to evaluate the behavior of bulk-fill composite restorations in posterior teeth (classes I and II). Methodology: Seventeen patients who required restorations on at least two posterior teeth were selected to participate in the study. The causes for indication of restorations were: replacement of deficient amalgam or composite resin restoration and/or caries lesion. In each patient, two restorations were performed. Randomly, one cavity was restored with Esthet-X HD nanohybrid composite (control group) and the other was restored with Esthet-X HD resin associated with the bulk-fill composite Surefil SDR Flow (test group). In both groups, a two-step total-etch adhesive system (XP Bond) was used. All patients received global treatment for carious activity. After a period of four years, the quality of the restorations was evaluated by a previously calibrated examiner, through a modification of the USPHS method and through the FDI method. The data were submitted to statistical analysis by the non-parametric Mann-Whitney test (p <0.05) and the intra-observer agreement was evaluated by Kappa test. Results: At the 4-year follow-up, 26 teeth (18 class I and 8 class II restorations) were evaluated, and no statistically significant differences between control and test groups were observed for both evaluation methods used. There were no failures in any of the restorations over time. Conclusion: The quality of class I and II restorations with bulk-fill resin was similar to that of conventional nanohybrid resin. The bulk-fill composite technique showed good clinical performance as well as the conventional one during the 4 years of follow-up.
810

Impact of Restoration Practices on Mycorrhizal Inoculum Potential in a Semi-Arid Riparian Ecosystem

January 2012 (has links)
abstract: Mycorrhizal fungi form symbiotic relationships with plant roots, increasing nutrient and water availability to plants and improving soil stability. Mechanical disturbance of soil has been found to reduce mycorrhizal inoculum in soils, but findings have been inconsistent. To examine the impact of restoration practices on riparian mycorrhizal inoculum potential, soil samples were collected at the Tres Rios Ecosystem Restoration and Flood Control Project located at the confluence of the Salt, Gila, and Agua Fria rivers in central Arizona. The project involved the mechanical removal of invasive Tamarix spp.( tamarisk, salt cedar) and grading prior to revegetation. Soil samples were collected from three stages of restoration: pre-restoration, soil banks with chipped vegetation, and in areas that had been graded in preparation for revegetation. Bioassay plants were grown in the soil samples and roots analyzed for arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) infection percentages. Vegetations measurements were also taken for woody vegetation at the site. The mean number of AM and EM fungal propagules did not differ between the three treatment area, but inoculum levels did differ between AM and EM fungi with AM fungal propagules detected at moderate levels and EM fungi at very low levels. These differences may have been related to availability of host plants since AM fungi form associations with a variety of desert riparian forbs and grasses and EM fungi only form associations with Populus spp. and Salix spp. which were present at the site but at low density and canopy cover. Prior studies have also found that EM fungi may be more affected by tamarisk invasions than AM fungi. Our results were similar to other restoration projects for AM fungi suggesting that it may not be necessary to add AM fungi to soil prior to planting native vegetation because of the moderate presence of AM fungi even in soils dominated by tamarisk and exposed to soil disturbance during the restoration process. In contrast when planting trees that form EM associations, it may be beneficial to augment soil with EM fungi collected from riparian areas or to pre-inoculate plants prior to planting. / Dissertation/Thesis / M.S. Applied Biological Sciences 2012

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