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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

Análise comparativa da dieta, seletividade alimentar e estrutura da ictiofauna, juvenis e espécies de pequeno porte, em lagoas marginais do reservatório de Rosana (Rio Paranapanema, SP/PR)

Feitosa, Mateus Ferrareze [UNESP] 28 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-28Bitstream added on 2014-06-13T20:26:40Z : No. of bitstreams: 1 feitosa_mf_dr_botib.pdf: 1038034 bytes, checksum: 025ed2cf3a99ff7d8beb8e163e5fb81a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente estudo foi conduzido em quatro lagoas marginais da porção superior do reservatório de Rosana, bem como no canal principal do rio Paranapanema. O objetivo do primeiro capítulo foi analisar a composição e os atributos ecológicos das assembléias fitoplanctônicas, recurso trófico primário das cadeias alimentares aquáticas. O segundo capítulo trata da comunidade zooplanctônica (Cladocera e Copepoda) e sua distribuição nos ambientes analisados. O terceiro trabalho procura avaliar se a introdução de uma espécie exótica de peixe (Cichla kelberi) pode causar alterações na estrutura da ictiofauna local, com uma possível redução da sua diversidade. Por fim, o quarto capítulo refere-se à alimentação da ictiofauna de pequeno porte, através da análise da dieta e do hábito alimentar das espécies, considerando principalmente a importância da comunidade planctônica para essa fauna. O número total de táxons de fitoplâncton identificados foi de 283. Zygnemaphyta foi o grupo com maior número de espécies, seguido por Chlorophyta e Bacillariophyta. Maior riqueza, abundância e biomassa de fitoplâncton foram observadas nas lagoas, especialmente durante o período chuvoso. O número total de táxons de zooplâncton identificados foi de 72. As lagoas laterais e o período chuvoso apresentaram maior abundância de organismos. Calanoida foi o grupo dominante nas assembléias zooplanctônicas. Os resultados mostraram que no sistema de lagoas laterais as comunidades são controladas por mecanismos ascendentes (“bottom-up”). Um total de 4693 peixes, pertencentes a 43 espécies foram amostrados. A Ordem Characiformes foi a mais abundante, seguida por Perciformes e Siluriformes. Não houve diferenças estatísticas na riqueza, na abundância, na biomassa, na média do comprimento, na composição das assembléias e na diversidade de peixes, comparando-se o período... / The study was carried out in four lateral lagoons of the tail region of Rosana reservoir, as well as in the river/reservoir main channel. The aim of the first chapter of the thesis was to analyze the composition and ecological attributes of the phytoplankton assemblages, primordial trophic resource of the aquatic food chains. The second chapter is focused on the zooplankton community (Cladocera and Copepoda) and their distribution in the study environments. The third chapter tries to assess whether the introduction of a non native fish species (Cichla kelberi) may promote alterations in the local ichthyofauna, with a possible reduction in its diversity. Finally, the last chapter discusses the ichthyofauna feeding, through the analysis of diet and feeding behavior of fish, considering mainly the importance of plankton organisms as a resource. The total number of phytoplankton taxa identified was of 283. Zygnemaphyta was the most specious group, followed by Chlorophyta and Bacillariophyta. Higher richness, abundance and biomass were observed in the lagoons, especially during the rainy period. The total number of zooplankton taxa was 72. Higher zooplankton abundance was observed in the lateral lagoons and in the rainy period. Calanoids were the dominant group in the zooplankton assemblages. The results indicated that in the lateral lagoons system, the communities are controlled by bottom-up mechanisms. A total of 4,693 fish, belonging to 43 species was sampled between 2004 and 2009. The order Characiformes was the most abundant, followed by Perciformes and Siluriformes. There were no differences in composition, richness, abundance, biomass, mean length and diversity, when compared the periods previous and after the introduction of Cichla. The results showed that the feeding of the river fish assemblages was different from the lagoons... (Complete abstract click electronic access below)
2

Functional Responses of Sonoran Desert Plant Species to Precipitation

Ignace, Danielle Denise January 2006 (has links)
Arid and semi-arid ecosystems of the southwestern U.S. are experiencing major changes that have profound impacts for community structure and ecosystem function. First, these ecosystems are experiencing dramatic shifts in vegetation composition as a result of the invasion of non-native species. Second these ecosystems are predicted to undergo substantial shifts in climate regime, which include increases in the variability and frequency of extreme temperature and precipitation events. It is not well understood how these current and predicted changes will affect the physiological performance of different plant types in arid and semi-arid ecosystems. To address the effect of these changes, this dissertation focused on the photosynthetic response of a native and non-native grass species, and dominant shrub species to precipitation across contrasting soil surfaces in southeastern Arizona. The native and non-native grasses were exposed to wet and dry seasonal precipitation and responses to precipitation events ('pulses') were measured over the course of a summer growing season. To gain a mechanistic understanding of these patterns, the biochemical and diffusion limitations to photosynthetic function were measured over the course of a pulse period. Building on this foundation, natural stands of the non-native grass species were exposed to sequences of different sized pulse events. The physiological performance of a dominant shrub species, Larrea tridentata, was measured in order to determine the biochemical and diffusional constraints to photosynthetic function across seasons and contrasting soil surfaces. The results showed that leaf area development of these grass species affects water availability and time lags in photosynthetic response. Initial soil moisture conditions across contrasting soil surfaces influence the magnitude of photosynthetic response in grasses. Large photosynthetic responses of the non-native grass require large and consecutive precipitation pulses. Co-limitation of photosynthesis of Larrea tridentata by diffusion and biochemistry does not illustrate typical trends across seasons and soil surfaces. Overall results demonstrate the importance of determining the mechanisms responsible for observed leaf-level photosynthetic patterns across individual pulse events, seasons, and contrasting soil surfaces. This is especially important for predicting the magnitude of the response of plant communities in arid and semi-arid ecosystems to species invasions and changes in climate.
3

Análise comparativa da dieta, seletividade alimentar e estrutura da ictiofauna, juvenis e espécies de pequeno porte, em lagoas marginais do reservatório de Rosana (Rio Paranapanema, SP/PR) /

Feitosa, Mateus Ferrareze. January 2011 (has links)
Orientador: Marcos Gomes Nogueira / Banca: Lilian Casatti / Banca: Mário Luís Orsi / Banca: Ricardo Motta Pinto Coelho / Banca: Ângelo Antônio Agostinho / Resumo: O presente estudo foi conduzido em quatro lagoas marginais da porção superior do reservatório de Rosana, bem como no canal principal do rio Paranapanema. O objetivo do primeiro capítulo foi analisar a composição e os atributos ecológicos das assembléias fitoplanctônicas, recurso trófico primário das cadeias alimentares aquáticas. O segundo capítulo trata da comunidade zooplanctônica (Cladocera e Copepoda) e sua distribuição nos ambientes analisados. O terceiro trabalho procura avaliar se a introdução de uma espécie exótica de peixe (Cichla kelberi) pode causar alterações na estrutura da ictiofauna local, com uma possível redução da sua diversidade. Por fim, o quarto capítulo refere-se à alimentação da ictiofauna de pequeno porte, através da análise da dieta e do hábito alimentar das espécies, considerando principalmente a importância da comunidade planctônica para essa fauna. O número total de táxons de fitoplâncton identificados foi de 283. Zygnemaphyta foi o grupo com maior número de espécies, seguido por Chlorophyta e Bacillariophyta. Maior riqueza, abundância e biomassa de fitoplâncton foram observadas nas lagoas, especialmente durante o período chuvoso. O número total de táxons de zooplâncton identificados foi de 72. As lagoas laterais e o período chuvoso apresentaram maior abundância de organismos. Calanoida foi o grupo dominante nas assembléias zooplanctônicas. Os resultados mostraram que no sistema de lagoas laterais as comunidades são controladas por mecanismos ascendentes ("bottom-up"). Um total de 4693 peixes, pertencentes a 43 espécies foram amostrados. A Ordem Characiformes foi a mais abundante, seguida por Perciformes e Siluriformes. Não houve diferenças estatísticas na riqueza, na abundância, na biomassa, na média do comprimento, na composição das assembléias e na diversidade de peixes, comparando-se o período... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study was carried out in four lateral lagoons of the tail region of Rosana reservoir, as well as in the river/reservoir main channel. The aim of the first chapter of the thesis was to analyze the composition and ecological attributes of the phytoplankton assemblages, primordial trophic resource of the aquatic food chains. The second chapter is focused on the zooplankton community (Cladocera and Copepoda) and their distribution in the study environments. The third chapter tries to assess whether the introduction of a non native fish species (Cichla kelberi) may promote alterations in the local ichthyofauna, with a possible reduction in its diversity. Finally, the last chapter discusses the ichthyofauna feeding, through the analysis of diet and feeding behavior of fish, considering mainly the importance of plankton organisms as a resource. The total number of phytoplankton taxa identified was of 283. Zygnemaphyta was the most specious group, followed by Chlorophyta and Bacillariophyta. Higher richness, abundance and biomass were observed in the lagoons, especially during the rainy period. The total number of zooplankton taxa was 72. Higher zooplankton abundance was observed in the lateral lagoons and in the rainy period. Calanoids were the dominant group in the zooplankton assemblages. The results indicated that in the lateral lagoons system, the communities are controlled by bottom-up mechanisms. A total of 4,693 fish, belonging to 43 species was sampled between 2004 and 2009. The order Characiformes was the most abundant, followed by Perciformes and Siluriformes. There were no differences in composition, richness, abundance, biomass, mean length and diversity, when compared the periods previous and after the introduction of Cichla. The results showed that the feeding of the river fish assemblages was different from the lagoons... (Complete abstract click electronic access below) / Doutor
4

Abundance Trends and Drivers of Change in Freshwater Fish Communities of the New River Basin

Sleezer, Logan J. 25 June 2020 (has links)
Habitat destruction/alteration and non-native species are widely considered the two most serious threats to biodiversity within freshwater ecosystems, which are among the most threatened in the world. I examined the effects of these factors, specifically focusing on land use and non-native species as drivers of abundance patterns of native fishes in the highly invaded and anthropogenically impacted New River basin (NRB) in the Appalachian region of the United States. In chapter 2, I examine current native and non-native species abundance patterns related to the highly variable land-use mosaic present across the NRB, with specific focus on the species-specific effects of intensive land-use practices (agriculture and urbanization) at varying spatial extents (upstream watershed, upstream riparian, and local riparian). In chapter 3, I investigate historical context of basin-wide and site-level abundance spread and decline of natives and non-natives in the upper and middle New River basin (UMNR) over the past 60+ years. Finally, in chapter 4, I partition the variation in native species abundance explained separately by land use and non-native species to determine which factor might be most influential in describing abundance distributions of UMNR native fishes over the past 20+ years. My results indicate widely varying responses of native species to various combinations of intensive land use and non-native species across contributing watersheds and widespread biotic homogenization and native species declines over the past 60+ years. These declines include reductions in unique communities and endemic species provided little consideration or protection under current conservation law. I suggest potential avenues for improvement of conservation actions to help preserve these unique species and communities based on their responses to various land-use and non-native species stressors. My study framework should be broadly applicable to other drainages and should provide opportunities for early identification of potential native species declines and the stressors that may be contributing to them. / Master of Science / Freshwater fishes are experiencing world-wide declines that have the potential to cause major negative ecological and economic impacts. Two of the biggest contributors to fish declines are habitat destruction and non-native species introductions. I examined populations of numerous fish species in the New River basin (NRB) in the Appalachian region of the United States to identify declining native species and determine how intensive land use (one type of habitat destruction) and non-native species may be contributing to these trends. My results suggest that nearly half of the native species occurring in the NRB may be experiencing widespread reductions in abundance. As a result of these declines and the spread of a few common native and non-native species, fish communities across the NRB are becoming less unique over time. Land-use changes, such as agricultural and road development near streams, which contribute to increased soil erosion and run-off of silt and sand into streams, could be causing broad habitat changes that lead to diminished populations of sensitive species and overall local and regional fish diversity. While no single non-native species may be held responsible for all native fish species declines in the NRB, complex interactions, such as competition and predation, between many natives and non-natives altogether could be contributing to many native fish declines. Farmers and other landowners can help to prevent future fish declines by re-establishing natural vegetation, such as trees, along streambanks and implementing other practices, such as cattle fencing, that reduce the streambank and soil erosion that harms fish habitat. Other stakeholders, such as anglers, can help prevent future native fish declines by limiting introductions of additional non-native species. For example, these stakeholders could avoid releasing aquatic pets and live bait into NRB streams. These practices would help limit future negative impacts caused by non-native species.
5

Important pests and diseases of plantation grown Pinus and Eucalyptus in Colombia and their control

Rodas Pelaez, C.A. (Carlos Alberto) 13 January 2013 (has links)
Colombia covers an area of approximately 114 million hectares (ha) of which the potential forestly land has been estimated at 60.7 million ha, about 53% of the total area. Only 54 million ha are considered as natural forest, leaving approximately 29 million ha to be used for livestock and agriculture. In order to provide an alternative source of timber, Colombian groups have planted approximately 327 000 ha to different species of Pinus, Eucalyptus and native species. This clearly represents only a small proportion of the total area that might be used for forestry, which is set to grow in the future. In general, trees established in plantations have been grown as monocultures that allow for substantial productivity per management unit. But this is also a homogeneous genetic resource that is highly susceptible to damage caused by insect pests and diseases. It is therefore, surprising that relatively little work has been conducted on pests and pathogens negatively affecting plantation foresty in Colombia. In this regard, the studies presented in this thesis present the first comprehensive treatment of the topic for the country. It is consequently hoped that these will form a basis for the future management and sustainability of forestry in Colombia. In the first Chapter of this thesis, I provide a historical background and the current pest and disease situation for the forestry sector in Colombia. This includes an overview of the main pest and diseases affecting commercial nonnative trees, especially species of Pinus and Eucalyptus. A wide range of sites occurring in Colombia were considered and the document also includes the impact of different climatic conditions on the incidence and management of the various pests and diseases treated. Some of the most important defoliators in Colombia reside in the order Phasmatodea and one of these, Litosermyle ocanae, was treated in studies presented in chapter two. The overall aim was to contribute basic knowledge of L. ocanae including an understanding of the biology, egg population dynamics, and potential biological control assessments based on early detection of the insect. vi Chapter three includes the discovery of one of the members of the Geometridae that causes serious damage due to defoliation of Pinus and Eucalyptus plantations. This pest, known as Chrysomima semiluteraria, has been known in Colombia for many years and this study included a comprehensive evaluation of its biology and field monitoring contributing to an Integrated Pest Management strategy for it. The insect was studied under field and laboratory conditions and a special emphasis was placed on its biological control using the egg parasitoid Telenomus alsophilae. Pinus plantations in Colombia have been affected by numerous pests, including recently, the adelgid Pineus sp. To establish management strategies to assist commercial forestry operations, the life cycle of this insect and the susceptibility of different Pinus species were determined in Chapter four. In addition, the possible role of a Ceraeochrysa sp. as a biological control agent was investigated. In chapter five, Fusarium circinatum is recorded for the first time on Pinus spp. in Colombia. The discovery of this fungus, known to cause the disease Pitch Canker has had an important impact on forestry, especially with regard to management strategies aimed at reducing its impact. Studies in this chapter included those to evaluate the susceptibility of families and provenances of Pinus spp., which are currently used in forestry planting programs in Colombia. The first emergence of the foliage pathogen Dothistroma septosporum as an important constraint to pine forestry in Colombia is treated in chapter six. This fungus is a serious pathogen of many species of Pinus around the world. It was, however, not recognised as a serious threat to forestry in Colombia until it emerged as a serious source of damage to Pinus tecunumanii. In this chapter, the aim was firstly to confirm the identity of the pathogen based on DNA sequence data. Subsequently, the host range and distribution of the pathogen was established in different Colombian forestry areas. The impact of the disease and the susceptibility of different provenances of P. tecunumanii was also assessed. In chapter seven, the main objective was to described the susceptibility of E. grandis clones to a new species of Ceratocystis and to identify clones resistant to it. The fungus was described as Ceratocystis neglecta and management strategies are suggested for it. This thesis includes two Appendices treating new reports of insect pests and an important Eucalyptus pathogen. In Appendix 1, I report on the importance of three different pest insects. Appendix 2 includes a description of a new disease, as well as the potential risks that this disease poses for the Colombian forestry sector. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Forestry and Agricultural Biotechnology Institute (FABI) / Unrestricted
6

Tourism Based on Reintroductions of Threatened Mammals: Achieving Positive Conservation Outcomes

King, Narelle Gaye, n/a January 2006 (has links)
Reintroduction programs have often been used to help redress serious declines across species' former ranges, but they suffer from high expense and low success rates. Tourism is one tool that could be used to support such programs, by generating funding for the programs and the local community, and by educating tourists about reintroductions and conservation. However, if tourism is not incorporated successfully into reintroduction programs, it may not provide any advantages and may even harm the reintroduction. There is a need to find ways to ensure efforts to integrate tourism and reintroductions achieve positive conservation outcomes. This is a topic that has been little researched to date. To achieve positive conservation outcomes, the enterprises must have financial sustainability and sustainable mammal populations. This thesis investigates ways to achieve these dual goals. The international literature is reviewed to establish what can be learnt from previous reintroduction attempts to increase the likelihood of reintroductions of mammals being successful. A number of broad measures are established, including starting the enterprises by reintroducing herbivores and early breeders, preferably wild caught, and then moving to carnivores or omnivores and captive-bred animals when staff have more experience. Some new ideas are developed for experimental releases that will add to the available knowledge on how to increase the chance of successful reintroductions. Tourism enterprises based on reintroductions of threatened native mammals in Australia and South Africa are reviewed. The review shows tourism enterprises based on reintroductions make significant contributions to conservation, but enterprises in Australia need to diversify further. It also describes a number of significant obstacles that enterprises in Australia and South Africa face in achieving financial sustainability and sustainable mammal populations. It then provides recommendations for dealing with the problems, such as employing staff or consultants with knowledge of wildlife management and marketing, and allowing tourists to view wildlife only on guided tours. Finally, the review identifies ways that government bodies in Australia could better facilitate enterprises based on reintroductions, such as making endangered species available free of charge or heavily subsidised at this stage, and then later running wildlife auctions. Legislation systems applying to tourism enterprises based on mammal reintroductions in Australia and South Africa are also reviewed. The review identifies a number of shortcomings of the current Australian legislation that affects the ability of government bodies to facilitate the development of such enterprises. Certain changes to the legislation are suggested. The international literature on factors influencing tourist satisfaction is reviewed and field research at an Australian case study site described, to determine ways tourism enterprises based on reintroductions can maximise tourist satisfaction. The field research draws out a number of new lessons for satisfying tourists, including: placing supplementary food or building waterholes in grasslands and areas with sparse vegetation; providing supplementary food for some species of wildlife; and providing pamphlets with information on the wildlife. The field research also illustrates some new ideas for tests to determine which methods should be used to maximise tourist satisfaction at a specific site, such as testing whether it is better to run tours in vehicles or on foot. The published international literature on minimising impacts of tourism on wildlife is reviewed and field research at one Australian case study site and one Chinese case study site described, to determine how to minimise the negative impacts of tourists on wildlife. The field research illustrates some new ideas for tests to determine which techniques should be used to minimise the impacts of tourism on wildlife at a specific site, such as tests to determine whether it is necessary to ensure tourists remain on the path at all times. The thesis then brings all these elements together into a flow chart giving recommendations to increase the rate of success of tourism enterprises that reintroduce mammals in achieving financial sustainability and sustainable mammal populations.
7

Temporal Currency: Life-history strategies of a native marine invertebrate increasingly exposed to urbanisation and invasion

Suwandy, Jason January 2012 (has links)
Biological invasions pose a serious threat to biodiversity world-wide. Through various means, such as competition or predation, invaders can radically change species composition and the functioning of native ecosystems. Even though our understanding of the mechanisms underlying invasion success is improving, there is still a lack of knowledge on the response of native species under pressure from invasion. This study adds to existing knowledge on the responses of a native species to invasion by non-indigenous species. Pyura pachydermatina is a native ascidian in the southeast coast of New Zealand currently under pressure from increased urbanisation and invasion by other ascidian species. The reproductive strategies employed by P. pachydermatina are investigated and the role of these strategies to increase its resistance to invasion are assessed. A population study on the status of P. pachydermatina around the Banks Peninsula was carried out in Camp Bay, Pigeon Bay, and Wainui. Spawning experiments using P. pachydermatina and gonad histology were done regularly during the one year study period to assess its ability to self-fertilise and determine its reproductive period. In addition, predation experiments were carried out to assess the susceptibility of P. pachydermatina early life stages to two amphipod predators. The surveys indicated that the populations of P. pachydermatina in the three sites are different from one another. Wainui has on average the largest individuals of P. pachydermatina and Camp Bay, the smallest. Abundance of P. pachydermatina was highest in Pigeon Bay and lowest in Wainui. The three life stages of Pyura pachydermatina; recruits, juveniles, and adults, were present in all sites at all seasons. The spawning experiments confirmed the species’ ability to self-fertilise and that it has a year-round spawning period. The two amphipod predators, Jassa marmorata and Caprella mutica, were efficient in consuming the egg and larval stages of P. pachydermatina, but did not feed on the settlers. Year-round reproduction and the ability to self-fertilise potentially give P. pachydermatina increased resistance to the effects of urbanisation and invasion. This population study suggested that the species is thriving around the Banks Peninsula. This, combined with previous studies on the non-indigenous ascidian Styela clava that stated the static or declining populations of the potential invaders, gives a positive outlook for the native species for the future. I suggest the use of genetic techniques to assess, in more detail, the population structure and dispersal potential of this native species. I also suggest constant monitoring of native species is required to keep up to date with the current status of the species, which will in turn help management decisions should regional spread of the Lyttelton S. clava invasion occur in the future.
8

Vztah mezi počtem druhů, teplotou, a úživností prostředí pro původní a nepůvodní druhy rostlin / Relationship between species diversity, temperature and productivity for native and non-native plant species

Szostoková, Kateřina January 2016 (has links)
Latitudinal gradient of diversity is typically being explained by the three main hypotheses: The Resources Limitation Hypothesis, The Speciation Rate Hypothesis and The Niche Conservatism Hypothesis. In my study I tested basic assumptions of these hypotheses using native and non-native vascular plants obtained from the new database GloNAF (Global Naturalized Alien Flora). I tested an effect of precipitation, NPP, temperature and historical velocity (difference in temperature and precipitation between the Last Glacial Maximum and present) on species richness. Given that the distribution of non-native species is among continents irregular (we can divide them into two groups - Australia with Europe and North America and South America with Africa and Asia), I tested the abovementioned relationships at both - global and continental scale. Species richness of native species increased with NPP, precipitation and temperature and decreased with the difference in temperature. The global distribution of non-native plants increased with precipitation and temperature velocity and decreases with temperature and precipitation velocity, although the results varied for particular continents. Unlike other studies the number of non-native species didn't correlate with the number of native plant species. Concurrently...
9

Respostas fisiológicas e morfológicas de mudas de landi (Calophyllum brasiliense cambess) a diferentes doses de glyphosate

Medeiros, Gessica Hashimoto de 03 March 2017 (has links)
As plantas daninhas se tornaram indesejáveis em áreas de plantio comercial florestal por competir por água, luz e nutrientes com as espécies florestais causando prejuízos, devido a isso devem ser controladas. Geralmente as áreas de empresas de plantio florestal são muito vastas, assim, o método de controle de plantas invasoras mais eficaz é o químico. O glyphosate é o herbicida mais utilizado para o controle de plantas daninhas devido ao fato de ser não-seletivo, possuir ação sistêmica, largo espectro de ação e custo relativamente baixo. Porém se não for aplicado de forma correta o produto poderá causar danos a espécies não-alvos. Esses danos dependerão das doses de glyphosate e da suscetibilidade da cultura. O Calophyllum brasiliense Cambess é uma espécie nativa de grande distribuição geográfica, possui madeira nobre e tem sido usada para reflorestamento em áreas alagadas. Nos últimos anos vem crescendo o interesse de empresas florestais por essa espécie. Assim, objetivou-se quantificar os efeitos morfológicos e fisiológicos de doses de glyphosate em mudas de Calophyllum brasililense Cambess. O experimento foi realizado na Universidade Federal do Tocantins, campus de Gurupi. O delineamento experimental foi o inteiramente casualizado (DIC) com 5 tratamentos (180, 360, 540 e 720 g e.a. L-1 de glyphosate Roundup Original® + testemunha sem aplicação) e 10 repetições, sendo cada planta uma repetição. Realizou-se análises morfológicas de toxicidade visual (7 em 7 DAA), altura e diâmetro (10 em 10 DAA), biomassa (MSC, MSF, MSR e MST), volume de raiz e área foliar (ao final do experimento) e análises fisiológicas utilizando equipamento IRGA para a avaliação de trocas gasosas: fotossíntese (A), condutância estomática (gs), transpiração (E) e carbono interno (Ci), sendo calculadas a eficiência instantânea do uso da água (EUA) e eficiência instantânea da carboxilação (EiC) através dos dados das trocas gasosas. Na menor dose (180 g e.a. L-1) as plantas foram se recuperando dos efeitos causados pelo glyphosate de modo que ao final do experimento os parâmetros fisiológicos se igualaram estatisticamente a testemunha. Porém as demais doses (360, 540 e 720 g e.a. L-1) afetaram significativamente tanto na morfologia quanto na fisiologia da espécie. / Weeds have become undesirable in commercial forest plantation areas because they compete for water, light and nutrients with forest species causing damage, due to this they must be controlled. Generally the areas of forest planting companies are very vast, thus, the most effective method of controlling invasive plants is the chemical. Glyphosate is the herbicide most used for weed control because it is non-selective, has a systemic action, broad spectrum of action and relatively low cost. However, if it is not applied correctly the product may cause damage to non-target species. These damages will depend on the doses of glyphosate and the susceptibility of the crop. Calophyllum brasiliense Cambess is a native species of great geographic distribution, has noble wood and has been used for reforestation in flooded areas. In recent years the interest of forest companies by this species has grown. Thus, the objective was to quantify the morphological and physiological effects of doses of glyphosate on calophyllum brasililense Cambess. The experiment was carried out at the Federal University of Tocantins, Gurupi campus. The experimental design was a completely randomized (DIC) with 5 treatments (180, 360, 540 and 720 g a.i. L-1 of glyphosate Roundup Original® + control without application) and 10 replicates, each plant being a repetition. Morphological analyzes of visual toxicity (7 in 7 DAA), height and diameter (10 in 10 DAA), biomass (MSC, MSF, MSR and MST), root volume and leaf area (at the end of the experiment) and physiological analyzes (A), stomatal conductance (gs), transpiration (E), and internal carbon (Ci). The instantaneous efficiency of water use (U) and instantaneous efficiency of carboxylation ( EiC) through gas exchange data. At the lowest dose (180 g a.i. L-1) plants were recovering from the effects caused by glyphosate so that at the end of the experiment the physiological parameters were statistically matched to the control. However, the other doses (360, 540 and 720 g a.i. L-1) significantly affected both the morphology and the physiology of the species.
10

Crescimento inicial e nutrição de Guanandi (Calophyllum brasiliense Cambèss) em função de N, P, K e saturação por bases do solo /

Ciriello, Valeria, 1976- January 2010 (has links)
Orientador: Iraê Amaral Guerrini / Banca: Dirceu Maximino Fernandes / Banca: Jacob Silva Souto / Resumo: Este trabalho avaliou o crescimento inicial do guanandi, em quatro experimentos instalados sob delineamento inteiramente casualizado, contendo seis tratamentos com quatro repetições, em vasos de 50 litros contendo mudas prontas para o plantio no campo, onde foram testadas doses crescentes de nitrogênio (N), fósforo (P), potássio (K) e níveis de saturação por bases (V%), visando obtenção de curvas de resposta da espécie. Os experimentos constituíram-se de doses crescentes de N (0/40/80/120/160 mg dm-3), de P (0/50/100/150/200 mg dm-3), de K (0/40/80/120/160 mg dm-3) e diferentes níveis de V% (0/20/40/60/80%), além da testemunha absoluta. O ensaio foi instalado sob estufa plástica situada na área experimental do Departamento de Recursos Naturais - Ciência do Solo, Faculdade de Ciências Agronômicas - UNESP/Botucatu, SP. Foram analisados mensalmente a altura e diâmetro do coleto e aos 10 meses de idade: a massa seca de folhas, caules, raízes e total, a área foliar e a análise química do material vegetal. As doses crescentes de N, P, K e os níveis de V% proporcionaram efeitos distintos com relação aos parâmetros avaliados. O guanandi apresentou baixa ou nenhuma resposta às adubações nitrogenada e potássica durante o período avaliado, demonstrando pequena exigência a esses nutrientes nesta fase de desenvolvimento. Os níveis de saturação por bases do solo também pouco influenciaram no crescimento dessa espécie. Para a adubação fosfatada, houve uma resposta altamente positiva, demonstrando ser imprescindível na implantação de reflorestamentos desta espécie em solos carentes em fósforo / Abstract: This study evaluated the guanandi growth in its early stage of development in 4 experiments, under a completely randomized design, containing 6 treatments and 4 replications, in 50 liters pots using seedlings ready for planting in the field, which was tested increasing doses of nitrogen (N), phosphorus (P) and potassium (K) and levels of bases saturation (V%), in order to obtainresponse curves of species. The experiments was consisted in using increasing doses of N (0/40/80/120/160 mg dm-3), P (0/50/100/150/200 mg dm-3), K (0/40/80/120/160 mg dm-3) and different levels of V% (0/20/40/60/80%), comparing to absolute control. The trial was conducted in plastic greenhouse located in the experimental area of Natural Resources Department - Soil Science, in the Agricultural Sciences College - UNESP / Botucatu, SP. Parameters analyzed werw: height, diameter, dry mass of leaves, stems and roots, leaf area, and chemical analysis of plant material. The increasing levels of N, P, K and V% provided different effects with respect to parameters. Guanandi had low or no response to nitrogen and potassium fertilization during the study period, showing little demand for these nutrients at this stage of development. The levels of saturation of the soil also had little influence on the growth of this species. For phosphorus, a highly positive response was demonstrated to be essential in the implementation of reforestation of this species in soils deficient in phosphorus / Mestre

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