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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.
151

Flora, vegetació i fitogeografia de la Marina Baixa

Solanas Ferrándiz, José Luis 25 October 1996 (has links)
No description available.
152

Estudo da microbiota conjuntival de cães portadores de Diabetes mellitus / Conjunctival flora in dogs with Diabetes mellitus

Shimamura, Graziele Massae 16 December 2008 (has links)
A microbiota normal exerce função protetora na superfície ocular, competindo por nutrientes e secretando substâncias com propriedades bactericidas, o que dificulta a invasão de patógenos. Animais diabéticos apresentam diferentes alterações ceratoconjuntivais, tais como maior concentração de glicose no filme lacrimal, menor quantidade e qualidade da lágrima e diminuição da sensibilidade corneal, diferenças clinicamente relevantes que podem alterar essa microbiota. Traumas oculares também podem apresentar tal alteração por promoverem a quebra da barreira de proteção da superfície ocular. A correta identificação do agente etiológico, além de proporcionar um tratamento eficiente em alterações oculares, direciona a antibioticoterapia profilática tópica nos casos cirúrgicos e evita o uso abusivo de antibióticos, o que pode levar a destruição da microbiota normal da superfície ocular, facilitando assim o crescimento de bactérias e fungos patogênicos. Com o intuito de minimizar as complicações pós-operatórias das cirurgias intra-oculares, como as facectomias, freqüentemente realizadas nos cães diabéticos por serem predispostos a apresentarem catarata, este estudo visou avaliar a prevalência dos principais microrganismos da microbiota conjuntival de cães diabéticos. Foram avaliadas as microbiotas conjuntivais de 29 cães diabéticos, atendidos no Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, totalizando 58 olhos. Estes, não estavam utilizando qualquer medicação tópica e não apresentavam alterações oculares ou doença sistêmica infecciosa que pudesse interferir nos resultados. As amostras foram colhidas do saco conjuntival com auxilio de zaragatoas, cuidando para que não houvesse contaminação pelo contato com pálpebras e cílios. As amostras foram inoculadas em meio enriquecedor Brain Heart Infusion (BHI) e caldo Sabouraud-dextrose e semeados em ágar sangue, MacConkey e Sabouraud-dextrose com cloranfenicol. Os microrganismos foram identificados por suas características morfológicas na bacterioscopia, pela coloração de gram e pelas características macro e microscópicas das colônias, além de testes bioquímicos. Houve maior prevalência de Staphylococcus (32,79%), principalmente coagulase negativos, que são os mais freqüentemente isolados nas infecções oculares: S. klosii, S. simulans, S. capitis, S. pasteuri, S. saprophyticus, S. haemolyticus. Também foram isolados Bacillus sp. (11,48%), S. intermedius (6,56%), Streptococcus sp (1,64%) e alguns fungos, como Cladosporium sp e Candida parapsilosis. Não houve crescimento de microrganismos gram negativos, anaeróbios estritos ou facultativos. Sugere-se que os resultados encontrados se relacionam diretamente às alterações ceratoconjuntivais dos animais analisados, local do exame, clima e diferentes raças. Sabendo-se que cães diabéticos são prováveis candidatos à facectomia, intervenção que promove quebra da barreira de proteção da superfície ocular e que existem microrganismos potencialmente patogênicos na conjuntiva destes animais, sugere-se análise da microbiota ocular antes da intervenção cirúrgica, para uso profilático de agentes antimicrobianos. / Normal ocular flora avoids infection depriving investor microorganisms of nutrients and by the secretion of bactericidal substances. Diabetic animals usually develop keratoconjunctival abnormalities, such as the higher concentration of glucose in the tear film; qualitative and quantitative tear deficiency and a decrease of the cornea sensitivity, what probably changes their conjunctival flora either. The same alteration may happen after ocular traumas, when the ocular barrier of protection is discontinued. The identification of agent etiology allows the efficient treatment of ocular infections, the prophylactic prescription of antibiotics before surgery and avoids destruction of normal ocular flora or multiplication of pathogens. Aiming to minimize complications on intraocular surgeries, such as facectomies, frequently realized in DM dogs for its predisposition to develop cataract, this study evaluated the prevalence of microorganisms in their conjunctival flora. The conjunctival flora of 29 diabetic dogs (58 eyes), attended at the Ophthalmology Service, of the Veterinary Hospital of the Veterinary College University of São Paulo were evaluated. These dogs werent using any kind of eyedrops, didnt present any ocular or systemic disease other than diabetes mellitus, what could change the results. Samples were taken with sterile swabs from the conjunctival sac and inoculated on Brain Heart Infusion (BHI) and Sabouraud-dextrose broth, then sown in blood agar, MacConkey and Sabouraud-dextrose-cloranfenicol. Contamination was avoided during procedure not touching the swab on eyelid or eyelashes. Microorganisms were identified by their morphological aspects at bacterioscopy, gram staining, macro and microscopy characteristics of the colonies and by biochemical tests. Staphylococcus presented the higher prevalence (32,79%), mostly the coagulase negative ones (S. klosii, S. simulans, S. capitis, S. pasteuri, S. saprophyticus, S. haemolyticus), which are frequently isolated from ocular infections. Either isolated, were Bacillus sp. (11,48%), S. intermedius (6,56%), Streptococcus sp (1,64%) and some fungus, such as Cladosporium sp and Candida parapsilosis. Gram negative bacteria, anaerobic stricts or facultative were not identified during the study. We suppose that these results are strictly correlated to keratoconjunctival alterations in DM dogs, procedure, weather and breed. We conclude that, as DM dogs presents potential pathogens on its conjunctiva and are probable candidates to cataract surgery, which discontinues the ocular barrier of protection, we suggest the identification of the agent etiology before surgery and the proper use of antibiotic before and after any intraocular intervention.
153

Cria ensacada brasileira em Apis mellifera L. no estado do Rio de Janeiro: perdas, zoneamento, Palinologia e Microbiologia. / Brazilian sac brood in Apis mellifera L. in the Rio de Janeiro state (Brazil): losses, zoning, Palinology and Microbiology.

Pacheco, Marta Rodrigues 13 September 2007 (has links)
Made available in DSpace on 2016-04-28T14:59:44Z (GMT). No. of bitstreams: 1 2007- Marta Rodrigues Pacheco.pdf: 2134632 bytes, checksum: a8aff3b9147f86aa61211a72ac73fd49 (MD5) Previous issue date: 2007-09-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The brazilian sac brood (BSB) is a described disease in Brazil that attacks honey bees when they are fed with the pollen of certain trees as Stryphnodendron (Mimosoidea), commonly known as barbatim?o . These plants contain toxic substances as tannins that lead to a high mortality at the pre-pulps. The crescent loss of hives at different periods and regions of Rio de Janeiro state associated to the difficulty of finding the trees suspected of being intoxicated near the infected apiaries permits suggesting a hypothesis that the disease is not caused by the barbatim?o pollen. It still raises hypothesis that the bee diseases represent a significant cause for the hives losses observed in the state of Rio de Janeiro. To verify the hypothesis it was evaluated a survey of beekeeping losses, it was analyzed the geographical overlap between occurrence of BSB and distribution of S. pollyphyllum and S. adstringens. And also for this reason it was made the check out the pollen consumption of these plants for the Apis at natural conditions and it was initiated microbiological and toxic investigations. For the first approach it was researched the extension, distribution and reasons for the hive losses and its relation to the bees diseases. For this, the 2006 apiarian census was consulted. A comparative study was done in relation to the area of occurrence of BSB and the simultaneous existence of Stryphnodendron and the pollinic types specially of the barbatim?o that were present in the hives samples. Finally it was isolated and identified bacteria, fungi and mycotoxins in the apiarian pollen, bee bread and dead larvae of bee hives with BSB. The results of the census allowed seeing that the bees disease was the main reason for the loss of the hives. There wasn t the superposition between the BSB Stryphnodendron in Rio de Janeiro. It wasn t observed Stryphnodendron pollen in none of the analyzed samples. The results suggest that the disease that occurs in Rio de Janeiro state with similar symptoms to BSB is not caused by barbatim?o pollen. The Anadenanthera pollen was the majority in the study regions. Bacillus was the most frequent bacteria genus and the species were B. thuringiensis, B. alvei, B. apiarius, B. megaterium and B. polymyxa. The mycobiota was mainly composed of Penicillium and Aspergillus, with two potentially pathogenic and toxic species: A. niger and A. parasiticus. Aflatoxins B1 and G1 were presented in apiarian pollen and bee bread samples of a studied apiarian. It is necessary to realize other researches to confirm the etiology of BSB in the state of Rio de Janeiro. / A cria ensacada brasileira (CEB) ? uma doen?a descrita no Brasil que acomete as larvas de abelhas mel?feras quando s?o alimentadas com o p?len de algumas ?rvores tais como Stryphnodendron (Mimosoidea), conhecidas popularmente por barbatim?o . Estas plantas cont?m subst?ncias t?xicas, como os taninos, que provocam uma alta mortalidade nas larvas pr?-pupas. A crescente perda de colm?ias em diferentes ?pocas e regi?es do estado do Rio de Janeiro associada ? dificuldade de encontrar as ?rvores incriminadas como t?xicas nas proximidades de api?rios afetados pela CEB, permite sugerir a hip?tese de que a doen?a n?o ? causada pelo p?len do barbatim?o neste estado. Levanta-se ainda a hip?tese de que as doen?as de abelhas representam uma causa significativa para as perdas de colm?ias observadas no estado do Rio de Janeiro. Para testar estas hip?teses, objetivou-se fazer um levantamento da ocorr?ncia de perdas de colm?ias, analisar a sobreposi??o da CEB com a distribui??o geogr?fica de S. pollyphyllum e S. adstringens, verificar o consumo do p?len destas plantas pelas Apis em condi??es naturais e iniciar investiga??es microbiol?gicas e toxicol?gicas. Na fase preliminar, pesquisou-se a extens?o, distribui??o e causas de perdas de colm?ias e a sua rela??o com as doen?as de abelhas. Para isto, foram levantados dados de perdas relativos ao censo ap?cola elaborado no estado do Rio em 2006. Realizou-se tamb?m um estudo comparativo entre o zoneamento da CEB e o de Stryphnodendron no estado do Rio de Janeiro. Posteriormente, buscaram-se os tipos pol?nicos, especialmente de barbatim?o , presentes em amostras de colm?ias localizadas em regi?es de ocorr?ncia da CEB. Finalmente, isolaram-se e identificaram-se bact?rias e fungos presentes em amostras de p?len ap?cola, p?o de abelhas e larvas mortas de colm?ias com CEB, e investigou-se a presen?a de micotoxinas. Resultados do censo do estado mostraram que as doen?as de abelhas constitu?ram a principal causa de perdas de colm?ias. N?o houve sobreposi??o entre a ocorr?ncia da cria ensacada brasileira e a de Stryphnodendron no estado do Rio de Janeiro e tamb?m n?o foi observado p?len de Stryphnodendron em qualquer amostra analisada, indicando que: a doen?a que ocorre no estado do Rio de Janeiro com sintomas semelhantes a CEB n?o ? causada pelo p?len de barbatim?o . Prevaleceu durante a CEB p?len de Anadenanthera. Bacillus foi a bact?ria mais freq?ente, identificando-se: B. thuringiensis, B. alvei, B. apiarius, B. megaterium e B. polymyxa. A micobiota foi composta principalmente por Penicillium e Aspergillus, este com duas esp?cies potencialmente patog?nicas e tox?genas: A. niger e A. parasiticus. Aflatoxinas B1 e G1 estiveram presentes em amostras de p?len ap?cola e p?o de abelhas de um api?rio pesquisado. Faz-se necess?rio realizar outros estudos para afirmar a etiologia da CEB no estado do Rio de Janeiro.
154

Caracterização florística, estrutural e da dinâmica da regeneração de espécies nativas em um povoamento comercial de Eucalyptus grandis em Itatinga, SP. / Floristic structural characterization and dynamic regeneration of native species on a commercial stand of eucalyptus grandis in Itatinga, São Paulo.

Carneiro, Paulo Henrique Marostegan e 25 April 2002 (has links)
Os objetivos deste trabalho foram analisar a composição florística, a estrutura, alguns aspectos da dinâmica da regeneração de espécies nativas no sub-bosque de povoamentos comerciais de Eucalyptus spp e estudar o impacto que algumas práticas silviculturais (desbaste e corte raso) sobre a regeneração. Para isso, foram locadas 17 parcelas (0,68 ha de área amostral) em um talhão de Eucalyptus grandis (Talhão 48), na Fazenda São José do Bromado, coordenadas geográficas 23°13’30’’S e 48°34’07’’W, município de Itatinga - SP. Na avalia ção da composição e estrutura da regeneração, realizada 30 meses após o corte da primeira rotação do povoamento de eucalipto, foram plaqueados e identificados todos os indivíduos arbóreos ou arbustivos com altura superior a 1,5m. O estudo da evolução temporal da regeneração foi realizado em 2 avaliações, 30 e 45 meses após a exploração do povoamento de eucalipto, utilizando o mesmo método de análise, sendo considerado morto o indivíduo amostrado nos levantamento anterior e não localizado na avaliação seguinte. Após a segunda avaliação as parcelas foram divididas em três tratamentos, sendo: Tratamento 1 - testemunha (área amostral de 0,2ha), no qual o povoamento de eucalipto foi mantido, Tratamento 2 (área amostral de 0,24ha) no qual foi realizado o desbaste de 50% do povoamento de eucalipto e Tratamento 3 (área amostral de 0,24ha) no qual foi realizado o corte raso do eucalipto. Após a implantação dos tratamentos (46 meses após a exploração do povoamento) foram realizadas duas avaliações, a primeira 54 meses e a segunda 61 meses após a exploração da primeira rotação do povoamento de E. grandis. Foram amostrados 1900 indivíduos (104 espécies e 38 famílias) na primeira avaliação. A família de maior riqueza florística foi Myrtaceae seguida de Asteraceae, Fabaceae e Solanaceae, sendo esta última a que apresentou a maior densidade de indivíduos. As espécies de maior densidade relativa foram Solanum variabile e Matayba elaeagnoides. 76,66% dos indivíduos amostrados pertenciam a famílias que apresentaram padrão de distribuição espacial agregado. Na avaliação da dinâmica da regeneração, constatou-se que o recrutamento de novos indivíduos no sub-bosque do eucalipto no período de 30-45 meses da exploração comercial se concentrou nos grupos de espécies secundárias iniciais, secundárias tardias e espécies típicas da condição de sub-bosque. Enquanto a mortalidade se concentrou nos indivíduos pertencentes ao grupo das espécies pioneiras e das espécies não classificadas sucessionalmente. No período o índice para diversidade de Shannon (H´), apresentou crescimento de 3,48 para 3,573, e a equabilidade (J’), crescimento de 0,751 para 0,762, mostrando que houve ganho em relação a diversidade de espécies na área. No estudo do impacto que diferentes práticas silviculturais impõem a regeneração, o tratamento 1 - testemunha foi o que apresentou as menores taxas de mortalidade e o maior ingresso de espécies no período analisado. As operações de corte e remoção causaram grande impacto nos tratamentos 2 - desbaste de 50% do povoamento de E. grandis e tratamento 3 - corte raso, aumentando a taxa de mortalidade e diminuindo a taxa de recrutamento de indivíduos na regeneração. O Tratamento 2 foi o único a apresentar ganhos em diversidade (H’) em todos os levantamentos. / The objectives of this study were to analyze a floristic composition, the structure, some aspects of the dynamics of regeneration of native species in understory of commercial stands of Eucalyptus spp and to study the impact that some silvicultural practices (thinning and clear cut) have on regeneration. For this purpose, 17 samples (0.68 ha total sample area) were located in a stand of Eucalyptus grandis (Stand 48), on the São José do Bromado Farm, geographical coordinates 23°13’30’’S and 48°34’07’’W, municipal of Itatinga, Sao Paulo. In the evaluation of the composition and structure of the regeneration, done 30 months after the clear cut of the first rotation of Eucalyptus grandis, all of the individual trees up to 1.5m of height were tagged and identified. The study of the temporal evolution of regeneration was done in 2 evaluations, 30 and 45 months after the clear cut of the stand. The same method of analysis was used, being that the individual trees measured previously and not found in the second evaluation were considered dead. After the second evaluation the samples were divided into three treatments: Treatment 1- control (sample area of 0.2ha), of which the trees were maintained, Treatment 2 (sample area of 0.24ha), of which 50% thinning was done, and Treatment 3 (sample area of 0.24ha), of which clear cut was done. After the implementation of the treatments (46 months after the exploration), two evaluations were accomplished. The first at 54 months and the second at 61 months, after the exploration of the first rotation of the stand. One thousand nine hundred trees (104 species and 38 families) were sampled in the first evaluation. The largest floristic family verified was Myrtaceae followed by Asteraceae, Fabaceae and Solanaceae, the family which presented the largest density of individuals. Whereas the species with the greatest relative density were Solanum variabile and Matayba elaeagnoides. Among the individual samples, 76.66% were of the families that present a pattern of aggregate spatial distribution. In evaluating the dynamics of regeneration, it was found that the recruitment of new individuals in understory of eucalyptus during the period of 30-45 months after the commercial exploration was focused on the groups of initial secondary species, late secondary and typical species of understory. The mortality was concentrated in the group of pioneer species and non-classified species, respectively. The index period to the Shannon diversity (H’), presented growth of 3.48 to 3.573, and eqüability (J’), growth of 0.751 to 0.762, showing to have gained in relation to the diversity of species of the area. The study of the impact that different silvicultural practices have on regeneration, treatment 1- presented the least incidence of mortality and the greatest incidence of species during the analysis period. The practices of thinning and clear cut caused a great impact on treatments 2 and 3, improving the incidence of mortality and decreasing the incidence of new individuals of regeneration. Treatment 2 was the only one to present gains in diversity (H’) in all of the evaluations.
155

The Effect of Cigarette Smoke on the Microbiota or the Normal Flora of the Nasal Cavity

Osazee, Osarueme J., Idemudia, Monday I., Veeranki, Sreenivas P., Cao, Yan, Zheng, Shimin 08 April 2015 (has links)
Introduction. The adverse health effects of cigarette smoking are well established, including the direct effects of nicotine on human endothelial cells and fibroblasts. However, the direct effects of nicotine in the nasal cavity remain uninvestigated. The study aim was to ascertain the direct effect of chemical components in cigarette smoke on the microbial flora or microbiota of the nasal cavity. Methods. We enrolled 40 participants from the Benson Idahosa University’s Health clinics to conduct this study. Information on demographic characteristics including age, sex, and smoking duration was obtained at baseline. We collected nasal swabs of 20 smokers and 20 non-smokers. The wool content of the swap stick was immediately stored in mac Cathy bottles containing 9 ml of normal saline and transported to the laboratory in less than 45 minutes after collection for microbiological analysis under aseptic condition. The enumeration of the microorganisms was carried out using the streak and pours plate method on Nutrient agar, Blood agar, Chocolate agar, Mac coney agar and Potato Dextrose agar (PDA). A two-sample t-test was used to determine differences in enumeration of microorganisms and isolates between smokers and non-smokers. Results. Total bacterial counts for the smokers ranged from 177 - 307 x 102 cfu/ml and 223 - 551 x 102 cfu/ml for non-smokers with (p = 0.046 Nutrient agar, and p = 0.011 PDA). The bacteria isolates were identified as Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Proteus vulgaris and Streptococcus pneumonia, and the fungi isolates were identified as Aspergillus niger, Rhizopus stolonifer, Tricoderma viridae, respectively. The mean of nutrient agar in smokers is significantly lower (12.10) than that in nonsmokers (19.35), and the mean of PDA in smokers is significantly higher in smokers (5.75) than in nonsmokers (2.35). Higher percentages of gram-negative rods including Klebsiella pneumoniae (20%), Escherichia coli (20%) and Proteus vulgaris (20%) were identified in the smokers, which is in contrast to higher percentage of gram-positive cocci including Staphylococcus aureus and Streptococcus pneumonia identified in non-smokers. The most commonly isolated fungus in smokers was Aspergillus niger (45%) and nonsmokers was Rhizopus stolonifer (60%). Conclusions. Study findings demonstrated increased bacterial count and isolates in nasal cavity of smokers than non-smokers. Future studies should be warranted to understand the mechanistic role of nicotine in influencing microbiota of the nasal cavity.
156

La protección de las especies silvestres: especial tratamiento de la protección in situ

Barrena Medina, Ana María 20 December 2012 (has links)
No description available.
157

Additions to the Vascular Flora of the Rocky Fork Tract, Tennessee, USA

Levy, Foster, Donaldson, James T. 01 January 2018 (has links)
An examination of previously unaccessioned and overlooked specimens has added 16 species to the vascular flora of the 3800 ha Rocky Fork Tract in northeastern Tennessee. One species was deleted because of a prior misidentification for a net gain of 15 species and a total of 764 species. One species, Solidago lancifolia (Torr. ex A. Gray) Chapm., is listed as Endangered in Tennessee. All additions except two, represent county records. ©2018 Botanical Research Institute of Texas.
158

Evaluación de la propagación de plantas para restauración del hábitat del picaflor de arica (Eulidia yarrellii) en el Valle de Chaca, Región de Arica y Parinacota / Evaluation of the propagation of plants for the habitat restoration of chilean woodstar (Eulidia yarrellii) in the Chaca Valley, Region of Arica and Parinacota

Cozano Vásquez, Miguel Ángel January 2014 (has links)
Memoria para optar al título profesional de: Ingeniero en Recursos Naturales Renovables / El picaflor de Arica, Eulidia yarrellii, es una especie en serios problemas de conservación, siendo la destrucción de su hábitat producto del cambio del uso de suelo dos de las mayores presiones sobre su abundancia poblacional. En esta memoria de título se evaluó la factibilidad de propagar siete especies vegetales enfocadas a la restauración de hábitat de esta especie en el valle de Chaca. En el primer experimento, tres de las especies se dispusieron en parcelas de propagación en la zona de estudio, sometidas a tratamientos de riego y separadas en parcelas. Al cabo de 43 días se analizó la emergencia y a los cinco meses la sobrevivencia. Glandularia gynobasis no germinó en ninguna parcela, mientras que la emergencia de Trixis cacalioides se relacionó positivamente con las variables % de arena, riego y su interacción (p<0,05). La emergencia de Pitraea cuneato-ovata se relacionó negativamente con la variable % de limo (p<0,01). El segundo experimento intentó propagar cinco especies mediante estacas. Los resultados fueron ineficientes, logrando sobrevivir sólo tres individuos de T. cacalioides. Esta última especie fue la utilizada en el tercer experimento, también basado en propagación por estacas, donde se contrastaron hormonas de enraizamiento y sustratos (compost-arena versus perlita). Se registró una mayor sobrevivencia de individuos en el sustrato perlita, mayor longitud acumulada y largo de raíces para el tratamiento con ácido indol butírico. Se discutieron los resultados basados en técnicas de propagación establecidas, encontrando posibles razones a las cifras obtenidas. Se entregan recomendaciones para mejorar la propagación de las especies trabajadas y mantenerlas en buenas condiciones antes y durante su disposición final. Hacia el final de esta memoria se concluye la importancia que significa el conocer más la ecología y fisiología de las especies de plantas del desierto chileno, particularmente en el ámbito de la restauración ecológica. / The Chilean Woodstar, Eulidia yarrellii, is a seriously endangered species. Habitat destruction due to land use change is the main pressure factor for population numbers. This thesis was aimed at propagating seven plant species potentially useful for the restoration of the species' habitat in the Chaca Valley. In the first experiment, three species were placed in propagation plots in the area of study, under different irrigation treatments. After 43 days and five months, emergence and survival were analyzed, respectively. Glandularia gynobasis did not germinate in any plot, while Trixis cacalioides germination rate was positively related with variables such as % of sand, irrigation and their interaction (p<0.05). The germination on Pitraea cuneato-ovata looked to be related negatively with the variable % of silt (p<0.01). The second experiment included the propagation of 5 species by cuttings. The treatments were inefficient, with only three individuals of T. cacalioides surviving. This was the species used in the third experiment, also based on propagation by cuttings, where rooting hormones and substrates (compost-sand versus perlite) were contrasted. Increased survival of individuals was recorded on the substrate perlite and higher cumulative and long root length for indole butyric acid hormone treatment. Results were discussed, focusing on possible reasons for the obtained results. Recommendations are provided in order to improve the propagation of species worked and keep them before and during their final disposal. A conclusion of this thesis is the importance of increaing the knowledege on the ecology and physiology of the plants of the deserts of Northern Chile, particularly in the context of ecological restoration.
159

Sistema de automatización de informes de levantamiento de flora

Moreno Palma, Edward Johans January 2018 (has links)
Ingeniero Civil en Computación / Hoy en día, la automatización de procesos manuales permite en las empresas logran optimizar su tiempo para poder utilizarlo en otros recursos. A continuación se presenta la finalización de la construcción de un sistema capaz de dar apoyo en este sentido a la parte medioambiental de una empresa, específicamente en todos los procesos que son necesarios realizar para un correcto levantamiento de información de flora. Chile posee una amplia variedad de especies de flora registradas hasta la fecha, conocer todos sus nombres y modificaciones de los mismos es prácticamente imposible además de recordar cuales de ellas están en categoría de conservación, lo que es de vital importancia para un informe de flora. Para poder suplir esto, los especialistas llevan consigo libros con información de las especies existentes a terreno junto con un dispositivo GPS para ubicarse y un cuaderno para tomar notas de las especies observadas. Luego del proceso de toma de datos, los expertos deben generar listados con todas las especies vistas y verificar una por una cuales están en alguna categoría de conservación para agregar los datos correspondientes, además de comprobar que el nombre que se tiene de la especie es el último aceptado hasta la fecha del informe a entregar. Mientras tanto, por otro lado se tiene a una persona que está constantemente consultando por los avances llevados a cabo en cortos periodos de tiempo. Para solucionar lo anterior, se creó una herramienta computacional que permite la actualización de las especies de flora, almacenamiento de información de observaciones y generación de informes florísticos de manera automática por mencionar algunas funcionalidades que ayudan a los cuatro tipos de usuario: Administrador, Coordinador, Colector y Fiscalizador. Esta memoria describe el desarrollo de esta herramienta, la cual consiste en una aplicación móvil para Android junto con un sistema web de administración de datos. En este sistema se incorporaron dos extractores de información o crawlers que mensualmente recolectan los datos de la especies de flora presentes en Chile y también extraen la información correspondiente a todas las especies que están en alguna categoría de conservación vigente en el país. Junto con esto, se crearon interfaces en la aplicación móvil que son capaces de mostrar al usuario un mapa con los lugares donde debe realizar sus tomas de datos y actualizar el listado de especies a la última versión disponible. Además también se creó una vista web para que las personas que quieran estar al tanto del avance puedan hacerlo ingresando simplemente al sistema y, por último, se terminó la construcción de otra interfaz en la cual es posible descargar los informes finales que son necesarios para un correcto levantamiento de flora. El nuevo sistema brinda un ahorro de trabajo de gabinete que llega a los tres días según la empresa, permite la generación de informes automática con datos más completos de las especies y un cliente que puede supervisar el avance de sus proyectos en tiempo real.
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The ecology of subtidal turfs in southern Australia.

Russell, Bayden D. January 2005 (has links)
Assemblages of algae are altered by both bottom - up ( e.g. nutrient availability ) and top - down ( e.g. herbivory ) processes. As a result of the increasing human population in coastal areas, massive changes are forecast to benthic habitats in response to increasing coastal nutrient concentrations and a reduction in consumers. To identify the scales over which nutrients may have an effect, abundance of turf - forming algae growing as epiphytes on kelp ( Ecklonia radiata ) were related to water nutrient concentration across temperate Australia. In general, the percentage cover of epiphytes was greatest at sites with the greatest nutrient concentrations. By experimentally elevating mean nitrate concentration from the low 0.064 ± 0.01 µmol L [superscript - 1 ] to 0.121 ± 0.04 µmol L [superscript - 1 ], which was still only ~ 5 % of that measured on a more eutrophic coast, I was able to increase the percentage cover of epiphytes to match those seen on nutrient rich coasts, despite not matching the nutrient concentrations on those coasts. Hence, it appears that the effects of elevated nutrients will be disproportionately large on relatively oligotrophic coasts. Nutrient concentrations were also experimentally elevated to test whether the presence of an algal canopy or molluscan grazers were able to counter the effects of nutrient enrichment on algal assemblages. The loss of canopy - forming algae is likely to be a key precursor to nutrient driven changes of benthic habitats, because nutrients had no direct effect on algal assemblages in the presence of canopy - forming algae. In the absence of canopy - forming algae, space was quickly monopolised by turf - forming algae, but in the presence of elevated nutrients grazers were able to reduce the monopoly of turf - forming algae in favour of foliose algae. This switch in relative abundance of habitat may reflect greater consumption of nutrient rich turf - forming algae by grazers, possibly creating more space for other algae to colonise. Importantly, greater consumption of turf - forming algae in the presence of elevated nutrients may act as a mechanism to absorb the disproportionate effect of nutrients on oligotrophic coasts. In southern Australia, canopy - forming algae have a negative impact on the abundance of turf - forming algae. To assess the mechanisms by which an algal canopy may suppress turf - forming algae, abrasion by the canopy and water flow were experimentally reduced. Abrasion by the canopy reduced the percentage cover and biomass of turf - forming algae. In contrast to predictions, biomass and percentage cover of turf - forming algae were also reduced when water flow was reduced. Light intensity was substantially reduced when there was less water flow ( because of reduced movement in algal canopy ). However, the reduction in available light ( shading ) did not account for all of the observed reduction in biomass and percentage cover of turf - forming algae, suggesting that other factors are modified by water flow and may contribute to the loss of turf - forming algae. Habitat loss and fragmentation are well known to affect the diversity and abundance of fauna in habitat patches. I used experimental habitats to assess how fragmentation of turf habitats affects the diversity and abundance of two taxa of macroinvertebrates with different dispersal abilities. I established that increased isolation of habitats reduced the species richness and abundance of invertebrates with slow rates of dispersal, while the species richness and abundance of invertebrates with fast rates of dispersal were greatest in habitats that were far apart. In summary, this thesis provides an insight into some of the impacts associated with human populations in coastal areas, namely increased nutrient inputs, loss of grazers ( e.g. harvesting ), and loss of canopy algae and fragmentation of habitats. I show that increased nutrient concentrations in coastal waters can alter the relative abundance of algal species, and that some effects of elevated nutrients can be absorbed by the presence of grazers. I also show that elevated nutrients have no effect on algal assemblage in the presence of canopy - forming algae, and that canopies can suppress the colonisation of turf - forming algae. Finally, I show that the fragmentation of turf habitats affects taxa of invertebrates with different dispersal abilities in different ways. Whilst the contemporary ecology of much of the temperate Australian subtidal coast is considered to be relatively unaffected by human activity, this thesis shows that changes to top - down and bottom - up processes could have large consequences for habitats and their inhabitants. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2005.

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