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Relationships between body size, reproduction, and abundance in natural vegetationTracey, Amanda 31 July 2012 (has links)
According to traditional theory, superior competitive ability in plants generally requires a relatively large plant body size. Yet, within natural, crowded vegetation, most resident species are small, and species size distributions are right-skewed at virtually all scales. I aim to provide a potential explanation for this paradox: small species are able to coexist with and outcompete larger species because smaller species have greater ‘reproductive economy’—the ability for some seed production despite severe size suppression when under intense competition. Tracey and Aarssen (2011) found an isometric relationship between minimum reproductive threshold size (MRTS) and maximum resident plant size (MAX); however, a more accurate measure of maximum potential body size (MPBS) was needed (without competition), as typically the effects of competition are size-dependent. An isometric relationship, similar to Tracey and Aarssen (2011) was seen. Tracey and Aarssen (2011) also found that, contrary to the predictions of traditional theory, larger species were not more abundant (based on plot occupancy) in an old-field community. A more accurate measure of abundance was obtained by locating random 1 x 1 m plots and counting the number of ramets for each species in the plot. A significant negative relationship was seen between abundance and MRTS. This suggests that the most abundant plants in communities are not those that are bigger, or smaller, they are those with the smallest MRTSs. To test whether this relationship exists in other habitats, plots were located in different old-field, shrub-land and wood-land communities. Ramets for each species within the plots were counted, and the largest plant of each species was measured. Significant negative relationships between abundance and MAX plant body size were seen in the shrub-land and woodland sites; however, no relationship was detected in this old-field site. The data support the idea that smaller species have greater reproductive economy, but the mechanism remains unknown. These results suggest that a smaller plant body size results in more effective gene transmission into future generations in all habitat types and stages of succession and indicates a suggested paradigm shift in the predicted selection effects of competition on the evolution of plant body size. / Thesis (Master, Biology) -- Queen's University, 2012-07-30 11:56:23.999
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Evaluation of hierarchical segmentation for natural vegetation: a case study of the Tehachapi Mountains, CaliforniaJanuary 2013 (has links)
abstract: Two critical limitations for hyperspatial imagery are higher imagery variances and large data sizes. Although object-based analyses with a multi-scale framework for diverse object sizes are the solution, more data sources and large amounts of testing at high costs are required. In this study, I used tree density segmentation as the key element of a three-level hierarchical vegetation framework for reducing those costs, and a three-step procedure was used to evaluate its effects. A two-step procedure, which involved environmental stratifications and the random walker algorithm, was used for tree density segmentation. I determined whether variation in tone and texture could be reduced within environmental strata, and whether tree density segmentations could be labeled by species associations. At the final level, two tree density segmentations were partitioned into smaller subsets using eCognition in order to label individual species or tree stands in two test areas of two tree densities, and the Z values of Moran's I were used to evaluate whether imagery objects have different mean values from near segmentations as a measure of segmentation accuracy. The two-step procedure was able to delineating tree density segments and label species types robustly, compared to previous hierarchical frameworks. However, eCognition was not able to produce detailed, reasonable image objects with optimal scale parameters for species labeling. This hierarchical vegetation framework is applicable for fine-scale, time-series vegetation mapping to develop baseline data for evaluating climate change impacts on vegetation at low cost using widely available data and a personal laptop. / Dissertation/Thesis / M.A. Geography 2013
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Organização espacial da vegetação natural nas quadrículas de São Carlos e Brotas/SP / Spatial organization of natural vegetation in the quadrangle of São Carlos and Brotas/SPPeterlini, Rafael Frem, 1981- 08 October 2011 (has links)
Orientador: Archimedes Perez Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-19T08:14:53Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: Grande parte do progresso e da acumulação de capitais auferidos pelo estado de São Paulo ao longo dos séculos XIX e XX, que o tornaram o mais rico, desenvolvido, urbanizado e industrializado do país, se efetivaram graças à destruição de suas formações vegetais naturais. Substituída pelo crescimento de centros urbanos, distritos industriais, pecuária, agricultura e silvicultura, a vegetação de cerrado teve sua extensão territorial original reduzida a menos de 1% do total. Nesse contexto, levando em conta a presença simultânea dos Neossolos Quartzarênicos, a área objeto de estudo, constituída pelas Quadrículas de São Carlos e Brotas, é considerada um de seus últimos e mais significativos remanescentes. Dada essa situação, com base no estudo de toponímias, solos, formas de relevo, relatos de viajantes e trabalho de campo, o objetivo principal é propor um mapa da vegetação natural, outrora presente nesta área, a ser elaborado na escala de 1:50.000, abarcando a pretérita organização do cerrado, suas fitofisionomias e outras formações vegetais existentes. O êxito obtido na elaboração do mesmo, além de comprovar a eficácia dos elementos utilizados, mostrou ainda que os Neossolos Quartzarênicos, em sua extensão geográfica, davam aporte ao cerrado. O presente trabalho também se prestou a averiguar a alternância fitofisionômica da vegetação de cerrado, sendo notória a influência que as características físicas dos solos, principalmente a textura e sua mudança, exercem sobre o processo / Abstract: A great part of the progress and accumulation of capital granted by the State of São Paulo along the XIX and XX centuries, which made it the richest, most developed, urbanized and industrialized state in the country, were made effective thanks to the destruction of its natural vegetation. Substituted by the growth of the urban centers, industrial districts, cattle ranching, agriculture and forestry, the formation of the "Cerrado" had its original territorial extension reduced to less than 1% of the total. In that context, also considering the presence of the Inceptisols, the subject area of the study, limited by the quadrangle of São Carlos and Brotas, is considered one of its last and most significant reminiscent. Given the present situation, based on the toponimic and soil studies, forms of landscape, reports from travellers, and field research, the main objective is the proposal of a map of the natural vegetation, previously present in this area, to be elaborated in the scale of 1:50.000, enveloping the previous organization of the "Cerrado", its phytophysionomy and other existing vegetation formations. The success obtained in its elaboration, besides proving the efficiency of the elements used, has also shown that the "Cerrado", in its original spatial organization, occurred together with the Inceptisols. The present work has also been effective in checking the phytophysionomic alternance of the "Cerrado" vegetation. In this case, the influence that the physical characteristics of the soil - in particular the texture and its change - exert on the process is wellknown / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia
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Mapeamento retrospectivo da vegetação natural na região de Mogi-Mirim, Araras, São Carlos e Brotas - SP : uma proposta metológica / Retrospective mapping of the natural vegetation in the region of Mogi Mirim, Araras, São Carlos and Brotas - SP : a methodological proposalPeterlini, Rafael Frem, 1981- 27 August 2018 (has links)
Orientador: Archimedes Perez Filho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-27T09:59:41Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: Ao longo dos séculos XIX e XX, em meio às terras do interior paulista, a efetivação do processo de colonização, com a consequente conversão do solo em áreas urbanas, agropastoris e de silvicultura, transformou radicalmente a paisagem natural de outrora. Motivada pelos ideais de progresso e acumulação de riquezas, bem como pela crença acerca da inesgotabilidade dos recursos naturais, essa transformação reduziu a cobertura vegetal natural a milhares de fragmentos, muitos dos quais descaracterizados e sem quaisquer conexões entre si, bastando para isso, aproximadamente, cento e cinquenta anos de uso e ocupação. Elaborado na escala 1:50.000, a partir da utilização conjunta de uma série de elementos, tais como: fotoanálise dos mosaicos aerofotogramétricos, estudo dos solos, toponímias, formas de relevo, relatos de antigos viajantes e trabalho de campo, o mapeamento retrospectivo da vegetação natural demonstrou que, em período anterior à chegada dos primeiros colonizadores e suas frentes pioneiras, a região formada pelas quadrículas de Mogi-Mirim, Araras, São Carlos e Brotas/SP, detentora de um dos últimos e mais significativos remanescentes de cerrado de todo estado de São Paulo, era constituída por um mosaico de formações vegetais e fitofisionomias. Nela, a mata semidecídua ocupava os solos mais férteis e/ou as áreas mais elevadas e acidentadas do relevo local. As florestas paludosas ocorriam junto às planícies de inundação dos cursos d¿ água, associadas aos solos orgânicos e hidromórficos. Enquanto isso, o cerrado e o cerradão predominavam no relevo colinoso da Depressão Periférica, atrelados a solos pobres, de textura mais, ou menos arenosa. Proposto esse mapeamento, o presente trabalho avaliou, também, a influência exercida pela precipitação pluviométrica na diferenciação das formações vegetais e fitofisionomias mapeadas. Com base nos pluviogramas acumulados médios mensais, concluiu-se que, frente à textura, fertilidade e percentual de argila dos solos, ela possui uma importância secundaria, pois, ao longo das séries históricas consideradas, os volumes de chuva não variam suficientemente para explicar, de forma isolada, a presença das distintas vegetações naturais, outrora existentes na região estudada / Abstract: Over the nineteenth and twentieth centuries, in the midst of the land in the interior of the realization of the colonization process, with the consequent conversion of land in urban areas, agro-pastoral and forestry, radically transformed the natural landscape of the past. Motivated by the ideals of progress and accumulation of wealth, and by the belief about the inexhaustibility of natural resources, this transformation reduced the natural vegetation cover thousands of fragments, many of which uncharacterized and without any connections with each other simply by approximately one hundred and fifty years of use and occupation. Prepared at the 1:50.000 from the joint use of a number of elements such as: photoanalysis of aerophotogrammetric mosaics, the soil survey, place names, forms of relief, ancient travelers and fieldwork reports, the retrospective vegetation mapping natural shown that in the period before the arrival of the first settlers and their pioneer fronts, the region formed by squares of Mogi Mirim, Araras, São Carlos and Brotas ¿ SP, which holds one of the last and most significant remnants of "Cerrado" in every state of São Paulo, was made up of a mosaic of vegetation types and plant formations. In it, the semi-deciduous forest occupied the most fertile soils and / or the higher areas and rugged local relief. The swamp forests occur along the flood plains of water courses, associated with organic and lowlands. Meanwhile, the "Cerrado" and the "Cerradão" predominated in the hilly relief of the Peripheral Depression, linked to poor soils, more or less sandy texture. Proposed this mapping, the present study evaluated also the influence of rainfall in the differentiation of plant and mapped vegetation types formations. Based on the average monthly cumulative rainfall chart, it was found that, compared to the texture, fertility and soil clay percentage, it has a secondary importance because, over the considered time series, rain volumes do not vary enough to explain, in isolation, the presence of different natural vegetation, once existing in the study area / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutor em Geografia
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Comunidade de mamíferos terrestres de médio e grande porte da Escola do Meio Ambiente em Botucatu, São PauloFontoura, Anna Flávia January 2019 (has links)
Orientador: Elizabeth Moreira dos Santos Schmidt / Resumo: O Brasil possui a maior diversidade de espécies do mundo, grande parte está nos biomas Mata Atlântica e Cerrado, considerados hotspots para conservação. Os mamíferos de médio e grande porte, grupo altamente afetados pela antropização, desempenham papéis importantes na dinâmica de ecossistemas, influenciam no ciclo do carbono, agem como predadores e dispersores de sementes, polinizadores, predadores de topo de cadeia alimentar. O presente estudo teve como objetivo realizar o levantamento da mastofauna terrestre de médio e grande porte presente na área da Escola do Meio Ambiente (EMA) no município de Botucatu, São Paulo e gerar dados de riqueza, ocorrência e frequência de ocorrência de espécies encontradas no local. A área da escola é de aproximadamente 12 hectares, apresentando cobertura vegetal de remanescente de Cerrado e fragmento com fitofisionomias de Mata Atlântica. As metodologias utilizadas foram: transectos, parcelas de areia e, como método complementar, o uso de armadilha fotográfica por dois meses. Adicionalmente, entrevista com funcionários para obtenção de dados. Foram registradas vinte espécies de mamíferos. A ordem carnívora foi a que apresentou mais espécies, oito no total. A espécie de maior ocorrência foi Hydrochoerus hydrochaeris, seguida por Canis lupus familiaris. Nas entrevistas, os funcionários citaram duas espécies que não foram registradas no estudo, Cavia aperea, mamífero de pequeno porte, e Lontra longicaudis. A riqueza constatada pelo estudo enfatiz... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil has the greatest diversity of species in the world, much of it in the biomes Cerrado and in the Atlantic Forest, considered hotspots for conservation. Medium and large mammals are one of the groups most affected by anthropization, play important roles in the nature of ecosystems, influence the carbon cycle, act as seed predators and seed dispersers, pollinators, top food chain predators. The present study had the objective of surveying the medium and large size terrestrial mastofauna present in Environmental School (EMA) area in the city of Botucatu, São Paulo, and to generate data on the richness, occurrence and frequency of occurrence of species found on the spot. The school area is approximately 12 hectares, presenting vegetation cover of Brazilian Savana remnant and fragment with phytophysiognomies of Atlantic Forest. Using the methodologies used were trawling for traces, sand plots and as a complementary method the use of photographic trap for two months, in addition, interview with employees to obtain additional data. Twenty species of mammals were recorded. The carnivorous order was the one that presented the most species, eight in total. The species with the highest occurrence was Hydrochoerus hydrochaeris, followed by Canis lupus familiaris. In the interviews, officials cited two species that were not recorded in the study, Cavia aperea, a small mammal, and Lontra longicaudis. The richness found by the study emphasizes the importance of the area for the persis... (Complete abstract click electronic access below) / Mestre
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Typologie, cartographie et évaluation des impacts anthropiques des séries de végétation forestière du Massif armoricain / Typology, mapping and anthropogenic impacts assessment of forest vegetation series in the armorican MassifChalumeau, Aurélie 18 December 2018 (has links)
Les premières utilisations des forêts par l’homme remontent au paléolithique ; depuis l’homme n’a cessé de modifier le couvert forestier. Après une introduction sur l’histoire de l’usage anthropique des forêts, trois questions de recherches sont posées : 1- Quelle est la composition des paysages forestiers ? 2- Comment se répartit le paysage végétal forestier ? 3- Comment peut-on évaluer l’impact des interventions humaines sur le paysage végétal forestier ? Le territoire d’étude est le Massif armoricain, territoire le moins boisé de France avec de grandes surfaces agricoles. Cette recherche s’inscrit dans le programme national de cartographie des végétations naturelles et semi-naturelles de France (CarHAB) initié en 2010 par le Ministère de la Transition écologique et solidaire, suivant une approche dynamico-caténale. La symphytosociologie et géosymphytosociologie s’intéressent à la fois aux aspects dynamiques (séries) et à l’intégration spatiale des communautés à différentes échelles (géoséries), et sont donc particulièrement adaptées à l’étude des écocomplexes forestiers. Une typologie des séries et des géoséries de végétation forestière du Massif armoricain est proposée. Une cartographie de la végétation actuelle (VA) et de la végétation potentielle naturelle (VPN) est réalisée sur des sites représentatifs du territoire d’étude. Enfin, une étude diachronique sur le massif d’Andaine (61) permet d’évaluer l’impact des activités humaines passées, actuelles, et de simuler l’évolution future du massif forestier. Ces informations, couplées à la carte de la VPN du site, permettent, de formuler des préconisations de gestion et de fournir aux gestionnaires un outil pour se rapprocher de la VPN, tout en conciliant une exploitation multifonctionnelle du site. / The first human uses of forests date back to the Paleolithic period. Since then, man has constantly modified the forest cover. Based on the history of human forest use, three research questions emerge: 1- what is the forest landscapes composition? 2- How is the forest vegetation landscape distributed? 3- How the human impact on the forest vegetation landscape could be assessed?To answer these questions, the armorican Massif, the most least-forested territory in France with large agricultural areas, is studied. This project is part of the CarHAB national program initiated by the FrenchEcological Ministry in 2010, based on a dynamiccatenal phytosociology approach. Symphytosociology and geosymphytosociology focus on both dynamical aspects (series) and spatial distribution of communities at different scales (geoseries), and are consequently particularly well-adapted for the forest ecocomplexes study. First, a typology of the forest vegetation series and geoseries in the armorican Massif is proposed. Then, a mapping of actual vegetation (VA) and potential natural vegetation (PNV) is done on study area representative sites.Finally, a diachronic study on the Andaine massif (61) is used to assess past and present human impact and to simulate the future evolution of the forest vegetation landscape. Those informations, combined with the PNV site map, are used to develop management guidelines and provide to forest managers a tool to get closer to the PNV while ensuring a multifunctional site operation at the same time.
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Miško žėlimo ir želdinimo būdų ekologinė ir ekonominė palyginamoji analizė / Forest regeneration and afforestation, ecological and economical ways of comparative analysisMineikis, Aurimas 17 June 2014 (has links)
Baigiamajame darbe analizuojami miško želdinių ir žėlinių ekologiniai ir ekonominiai panašumai, bei skirtumai. Darbo objektas – Radviliškio miškų urėdijos, Aukštelkų girininkijos žėliniai ir želdiniai. Darbo tikslas – nustatyti miško želdinimo ir žėlimo ekologinius ir ekonominius privalumus, bei trūkumus. Darbo metodai – Tyrimo bareliuose gautų faktinių duomenų ekologinė ir ekonominė analizė. Naudojami miško atkūrimo ir įveisimo nuostatai (7,8,9 priedai). Statistiniai skaičiavimai, urėdijos duomenų analizė. Darbo rezultatai. Atlikus tyrimus, pasirinktuose tyrimo bareliuose Radviliškio miškų urėdijoje, Aukštelkų girininkijos teritorijoje buvo nustatyta: Lf, Ud, Uf augavietėse ekologiniais aspektais tinkamiausias, mišrus atkūrimo būdas, išlaikantis biologinę įvairovę, tikslines medžių rūšis. Ekonominiu požiūriu mišrus atkūrimo būdas vidutiniškai reikalauja 4129 Lt/ha. lėšų, atkuriant želdiniais - 4615 Lt/ha. Mažiausiai reikalaujantis sąnaudų, tai paliekant kirtavietes savaiminiam žėlimui. Jų sąnaudos paruošiant dirvą, pašalinant žolinę augaliją chemiškai ar mechaniškai, bei pagal poreikį po kelių metų pašalinant nepageidaujamą augaliją mechaninių būdų yra - 2103 Lt/ha. Tai mažiausiai reikalaujantis atkūrimo sąnaudų ateities medynai, bet nėra tinkamiausi ekologiniu ir ekonominių (produktyvumo) atžvilgiu. / The final thesis compares and contrasts forest planting and natural vegetation from an ecological and economic point of view.
Object – Radviliskis forestry enterprise, Aukstelkai forestry district`s plantings and natural vegetation.
Aim – to determine ecological and economic advantages and disadvantages of afforestation and natural vegetation.
Methods applied – ecological and economic analysis of actual data obtained from the selected sample plots. Afforestation and reforestation regulations used (Appendixes 7, 8, and 9). Statistical calculations and analysis of the forestry enterprise’s data.
Results. Results of investigations in the selected sample plots at Radviliskis forestry enterprise, Auksteliai forestry district territory were as follows: the mixed reforestation method appears to be the most suitable method in Lf, Ud, Uf habitats from an ecological point of view as it helps maintaining biological diversity and target tree species. From an economic point of view, the mixed reforestation method requires approximately 4,129 Lt/ha while reforestation with planting requires 4,615 Lt/ha. The method that requires the modest expenditure is to leave the cleared space for natural regeneration. The expenditure for soil preparation, removal of grass vegetation with chemicals or mechanically, and mechanical removal of vegetation according to need after some years is 2,103 Lt/ha. Such kind of reforestation is the most cost-effective, yet it is not suitable from an ecological and... [to full text]
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Vliv pěstování jehličnatých monokultur na diverzitu rostlin / Effect of coniferous monoculture plantation on plant species dversityNěmeček, Jakub January 2012 (has links)
A structure and a function of a monoculture woodland is diferent from the natural woodland condition. This is an influence of a herb layer diversity. The change of the herb layer are mainly distinguishable in the case of tree coniferous monoculture. They are the poorest at all of them viewpoint diverzity. The diversity of the woodland was analysed with an insuffiently consequence. This study get the knowledge about the species composition and the diversity of these monoculture. At the same time get the knowlege about next factores, which change diversity and species composition of stand. As a confirmation of this, coniferous monoculture are numerously and species-compositionally diferent from broadleave monoculture. And more, coniferous trees change the enviroment's condition and the whole biotopes. There are not depend any species of the herb layer at the coniferous monoculture on this studied site of Křivoklátsko.
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Espécies de myrtaceae de uma parcela permanente de floresta ombrófila densa baixo montana no parque estadual Carlos Botelho, município de Sete Barras - SP. / Myrtaceae species in permanent plot in atlantic rain forest at Carlos Botelho state park, Sete Barras city - SP.Duarte, Alexandre Romariz 25 September 2003 (has links)
Com o objetivo de identificar as espécies arbóreas da família Myrtaceae, que estão presentes em uma Parcela Permanente no Parque Estadual Carlos Botelho, município de Sete Barras, foram realizadas onze expedições de coleta ao longo de um ano. Neste estudo foi realizado o levantamento das espécies arbóreas da família Myrtaceae, acima de 4,8 cm de DAP, em 256 sub-parcelas de 20x20m, totalizando uma área amostral de 10,24 ha. As identificações foram feitas com base na literatura, e posteriormente confirmadas através de comparação nos herbários ESA, SP, UEC e consulta a especialistas. Na Parcela Permanente foram identificadas 48 espécies da família, o que corresponde a aproximadamente 25% do total de espécies amostradas na área pelo projeto. No total foram encontrados 2254 indivíduos de Myrtaceae, o que corresponde a aproximadamente 20% do total de indivíduos arbóreos amostrados. Eugenia foi o gênero mais abundante com 26 espécies, seguido por Gomidesia e Marlierea com 4 espécies, Myrceugenia e Myrcia com 3, Campomanesia e Plinia com 2 espécies e Calycorectes, Calyptranthes, Myrciaria e Neomitranthes com 1 espécie. Os resultados obtidos permitem concluir que as espécies de maior frequência na área são Marlierea suaveolens Cambess., Eugenia cuprea (O. Berg) Nied., Gomidesia flagellaris D. Legrand, Marlierea tomentosa Cambess., e Neomitranthes glomerata (D. Legrand) D. Legrand em ordem decrescente. Elaborou-se também uma chave dicotômica, que em conjunto com o registro fotográfico das espécies ilustram o trabalho e auxiliarão na identificação no campo e no herbário em projetos futuros. / The aim of this work was to identify tree species of Myrtaceae from Carlos Botelho State Park, Sete Barras city. In this area 256 permanent plots of 20x20m (total 10,24ha) were installed, and every tree above 4,8cm DBH was collected during eleven field trips that were made in one year. The identifications were based on bibliography and later, confirmed through comparison at the herbaria ESA, SP and UEC and consults to specialists. 48 species of Myrtaceae were found at the permanent plots, which means approximately 25% of the areas floristic composition. Total of 2136 specimes were collected, which means approximately 20% of the total number of trees on the area. Eugenia was the most abundant genera with 26 species, followed by Gomidesia and Marlierea with 4 species, Myrceugenia and Myrcia with 3 species, Campomanesia and Plinia with 2 species, and Calycorectes, Calyptranthes, Myrciaria and Neomitranthes with 1 species each. Marlierea suaveolens Cambess., Eugenia cuprea (O. Berg) Nied., Gomidesia flagellaris D. Legrand, Marlierea tomentosa Cambess., and Neomitranthes glomerata (D. Legrand) D. Legrand were the most frequent species in this order. A dichotomous key for the species is presented, which along with a photographic record, illustrate this work and will help the identification of specimes on the field and in herbaria in future projects.
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Morphometric and Landscape Feature Analysis with Artificial Neural Networks and SRTM data : Applications in Humid and Arid EnvironmentsEhsani, Amir Houshang January 2008 (has links)
This thesis presents a semi-automatic method to analyze morphometric features and landscape elements based on Self Organizing Map (SOM) as an unsupervised Artificial Neural Network algorithm in two completely different environments: 1) the Man and Biosphere Reserve “Eastern Carpathians” (Central Europe) as a complex mountainous humid area and 2) Lut Desert, Iran, a hyper arid region characterized by repetition of wind-eroded features. In 2003, the National Aeronautics and Space Administration (NASA) released the SRTM/ SIR-C band data with 3 arc seconds (approx. 90 m resolution) grid for approximately 80 % of Earth’s land surface. The X-band SRTM data were processed with a 1 arc second (approx. 30 m resolution) grid by the German space agency, DLR and the Italian space agency ASI, but due to the smaller X-SAR ground swath, large areas are not covered. The latest version 3.0 SRTM/C DEM and SRTM/X band DEM were re-projected to 90 and 30 m UTM grid and used to generate morphometric parameters of first order (slope) and second order (cross-sectional curvature, maximum curvatures and minimum curvature) by using a bivariate quadratic surface. The morphometric parameters are then used in a SOM to identify morphometric features (or landform elements) e.g. planar, channel, ridge in mountainous areas or yardangs (ridge) and corridors (valley) in hyper-arid areas. Geomorphic phenomena and features are scale-dependent and the characteristics of features vary when measured over different spatial extents or different spatial resolution. Morphometric parameters were derived for nine window sizes of the 90 m DEM ranging from 5 × 5 to 55 ×55. Analysis of the SOM output represents landform entities with ground areas from 450 m to 4950 m that is local to regional scale features. Effect of two SRTM resolutions, C and X bands is studied on morphometric feature identification. The difference change analysis revealed the quantity of resolution dependency of morphometric features. Increasing the DEM spatial resolution from 90 to 30 m (corresponding to X band) by interpolation resulted in a significant improvement of terrain derivatives and morphometric feature identification. Integration of morphometric parameters with climate data (e.g. Sum of active temperature above 10 ° C) in SOM resulted in delineation of morphologically homogenous discrete geo-ecological units. These units were reclassified to produce a Potential Natural Vegetation map. Finally, we combined morphometric parameters and remotely sensed spectral data from Landsat ETM+ to identify and characterize landscape elements. The single integrated data set of geo-ecosystems shows the spatial distribution of geomorphic, climatic and biotic/cultural properties in the Eastern Carpathians. The results demonstrate that a SOM is a very efficient tool to analyze geo-morphometric features under diverse environmental conditions and at different scales and resolution. Finer resolution and decreasing window size reveals information that is more detailed while increasing window size and coarser resolution emphasizes more regional patterns. It was also successfully applied to integrate climatic, morphometric parameters and Landsat ETM+ data for landscape analysis. Despite the stochastic nature of SOM, the results are not sensitive to randomization of initial weight vectors if many iterations are used. This procedure is reproducible with consistent results. / Avhandlingen presenterar en halvautomatisk metod för att analysera morfometriska kännetecken och landskapselement som bygger på Self Organizing Map (SOM), en oövervakad Artificiell Neural Nätverk algoritm, i två helt skilda miljöer: 1) Man and Biosphere Reserve "Eastern Carpathians" (Centraleuropa) som är ett komplext, bergigt och humid område och 2) Lut öken, Iran, en extrem torr region som kännetecknas av återkommande vinderoderade objekt. Basen för undersökningen är det C-band SRTM digital höjd modell (DEM) med 3 bågsekunder rutnät som National Aeronautics and Space Administration släppte 2003 för ungefär 80 % av jordens yta. Dessutom används i ett mindre område X-band SRTM DEM med 1 bågsekund rutnät av den tyska rymdagenturen DLR. DEM transformerades till 90 och 30 m UTM nätet och därav genererades morfometriska parametrar av första (lutning) och andra ordning (tvärsnittböjning, största och minsta böjning). De morfometriska parametrar används sedan i en SOM för att identifiera morfometriska objekt (eller landform element) t.ex. plan yta, kanal, kam i bergsområden eller yardangs (kam) och korridorer (dalgångar) i extrem torra områden. Geomorfiska fenomen och objekt är skalberoende och kännetecken varierar med geografiska områden och upplösning. Morfometriska parametrar har härletts från 90 m DEM för nio fönsterstorlekar från 5 × 5 till 55 × 55. Resultaten representerar landform enheter för områden från 450 m till 4950 m på marken dvs. lokal till regional skala. Inflytande av två SRTM upplösningar i C och X-banden har studerats för identifikation av morfometriska objekt. Förändringsanalys visade storleken av upplösningsberoende av morfometriska objekt. Ökning av DEM upplösningen från 90 till 30 m (motsvarande X-bandet) genom interpolation resulterade i en betydande förbättring av terräng parametrar och identifiering av morfometriska objekt. Integration av morfometriska parametrar med klimatdata (t.ex. summan av aktiv temperatur över 10° C) i SOM resulterade i avgränsningen av homogena geoekologiska enheter. Dessa enheter ha används för att producera en karta av potentiell naturlig vegetation. Slutligen har vi kombinerat morfometriska parametrar och multispektrala fjärranalysdata från Landsat ETM för att identifiera och karaktärisera landskapselement. Dessa integrerade ekosystem data visar den geografiska fördelningen av morfometriska, klimatologiska och biotiska/kulturella egenskaper i östra Karpaterna. Resultaten visar att SOM är ett mycket effektivt verktyg för att analysera geomorfometriska egenskaper under skilda miljöförhållanden, i olika skalor och upplösningar. Finare upplösning och minskad fönsterstorlek visar information som är mer detaljerad. Ökad fönsterstorlek och grövre upplösning betonar mer regionala mönster. Det var också mycket framgångsrikt att integrera klimatiska och morfometriska parametrar med Landsat ETM data för landskapsanalys. Trots den stokastiska natur av SOM, är resultaten inte känsliga för slumpvisa värden i de ursprungliga viktvektorerna när många iterationer används. Detta förfarande är reproducerbart med bestående resultat. / QC 20100924
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