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Influência de características edáficas na seletividade ambiental de espécies arbóreas ao longo de um gradiente topográfico em floresta de terra firme na Amazônia CentralGuedes, Alacimar Viana 28 March 2016 (has links)
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Previous issue date: 2016-03-28 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The Amazon forest is distinguished by being the largest natural reservoir of plant wealth of the planet, where different each of their forest habitats has very rich and wide variety of species, often unique to a particular environment. Understanding how plant species are organized in their environment and how they use available resources is an important tool for the management and conservation of biodiversity. Thus, this study aimed to group tropical tree species according to environmental heterogeneity of the area, focusing on chemical and physical variables soil. The study was conducted in two forest sites in Central Amazonia: (a) forest management company Mil Precious Woods (PWA), the municipality of Silves, and (b) Experimental Field of Embrapa, located in the Agricultural District Suframa (CEDAS) Rio Preto da Eva. They were inventoried eight (08) continuous hectares at each site. All individuals with DAP≥ 10 cm were marked and identified in 2014 and had their registered UTM coordinates. 200 soil samples were collected at a depth of 0-20 cm per area, which were submitted to chemical and particle size analysis. They were surveyed 5,040 individuals distributed among 356 species on the site and give in 4,279 individuals represented by 203 species in the PWA site, with 191 species exclusive to the site and give in 69 exclusive PWA site. Among the five most abundant species on the site CEDAS are Eschweilera bracteosa, Protium amazonicum, Eschweilera coriacea, oblongifolia Licania and Pouteria sp, corresponding to 21% of individuals. In the PWA site, are Trattinnickia burserifolia, Eschweilera coriacea, Ocotea neesiana, Eschweilera collina and Trymatococcus amazonicus, which together account for 22% of all individuals. Although they are the same forest type, the two sites have distinct floristic composition, showing no floristic and structural homogeneity in upland forest in Central Amazon. The canonical correspondence analysis (CCA) indicated a significant correlation between the distribution of tree species along the topographic gradient and soil variables, with more pronounced effect of soil texture. The results suggest that it is possible to separate groups of species on the basis of soil characteristics, and texture is the variable which best describes the distribution of species throughout the soil gradient, mediated by the topography variations. / A floresta amazônica distingue-se por ser o maior reservatório natural de riqueza vegetal do planeta, seus diferentes ambientes florestais possui elevada riqueza e ampla variedade de espécies, muitas vezes exclusivas de determinado ambiente. Compreender como as espécies vegetais se organizam no seu ambiente e como utilizam os recursos disponíveis representa importante subsídio para o manejo e conservação da biodiversidade. Assim, o presente trabalho teve por objetivo agrupar espécies arbóreas tropicais segundo a heterogeneidade ambiental da área, com foco em variáveis químicas e física do solo. O estudo foi realizado em dois sítios florestais na Amazônia Central: (a) área de manejo florestal da empresa Mil Madeiras Preciosas (PWA), município de Silves, e (b) Campo Experimental da Embrapa, localizado no Distrito Agropecuário da Suframa (CEDAS), Rio Preto da Eva. Foram inventariados oito (08) hectares contínuos em cada sítio. Todos os indivíduos com DAP≥ 10 cm foram marcados e identificados e tiveram suas coordenadas UTM registradas. Foram coletadas 200 amostras de solo na profundidade de 0-20 cm por área, que foram submetidas às análises química e granulométrica. Foram inventariados 5.040 indivíduos distribuídos entre 356 espécies no sítio CEDAS e 4.279 indivíduos representados por 203 espécies no sítio PWA, sendo 191 espécies exclusivas do sítio CEDAS e 69 exclusivas do sítio PWA. Entre as cinco espécies mais abundantes no sítio CEDAS encontram-se: Eschweilera bracteosa, Protium amazonicum, Eschweilera coriacea, Licania oblongifolia e Pouteria sp., correspondendo a 21% do total de indivíduos. No sítio PWA, encontram-se Trattinnickia burserifolia, Eschweilera coriacea, Ocotea neesiana, Eschweilera collina e Trymatococcus amazonicus, que juntas correspondem a 22% do total de indivíduos. Apesar de constituírem a mesma tipologia florestal, os dois sítios apresentam composições florísticas distintas, evidenciando não homogeneidade florística e estrutural em florestas de terra firme na Amazônia Central. A análise de correspondência canônica (CCA) indicou correlação significativa entre a distribuição das espécies arbóreas ao longo do gradiente topográfico e as variáveis edáficas, com efeito mais pronunciado da textura do solo. Os resultados sugerem que é possível separar grupos de espécies em função das variáveis edáficas, e que a textura é a variável que melhor explica a distribuição das espécies ao longo do gradiente de solos, intermediada pelas variações de topografia.
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Caracterização florística e classificação vegetacional de um fragmento florestal urbano do oeste do Paraná / Floristic characterization and vegetation classification of an urban forest fragment in the western Paraná, BrazilSilva, Jéssica Patrícia Borges da 28 June 2016 (has links)
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Previous issue date: 2016-06-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of this work was to define the vegetation type of the urban fragment 4 Parque Ecológico Paulo Gorski (PEPG) and evaluate the influences of the climate and 5 altitudinal environmental variables on the floristic composition. The total of 1332 6 arboreal individuals of circumference at breast height equal or greater than 15 cm, 7 totalizing 71 species, were sampled. In addition, 401 species from 12 works developed 8 in the Rainforest (RF), Deciduous Forest (DF), Semideciduous Forest (SF) and 9 Araucaria Forest (AF) from southern and southeastern Brazil were used to build a 10 matrix of relative abundance for the floristic similarity. The environmental variables 11 from PEPG and other fragments were extracted from WorldClim. The floristic 12 similarity was evaluated through a group analysis using Simpson's Paradox, and the 13 significance was evaluated through the similarity analysis. The environmental variables 14 were compared between groups through the one-way ANOVA test. The characteristic 15 species from each group were evaluated by a similarity percentage analysis. Three 16 coincidental groups were formed, with the following vegetation types: RF with 20% of 17 similarity, DF/SF with 39% and AF with 32%. Although the PEPG environmental 18 variables have shown themselves as intermediate between AF and DF/FS, this fragment 19 has grouped with other areas from AF.
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Contemporary gene flow, mating system, and spatial genetic structure in a Jequitibá-rosa (Cariniana legalis Mart. Kuntze) fragmented population by microsatellite markers / Fluxo gênico contemporâneo, sistema de reprodução e estrutura espacial de genótipos em população fragmentada de jequitibá-rosa (Cariniana legalis Mart. O. Kuntze) utilizando marcadores microssatélitesEvandro Vagner Tambarussi 17 February 2014 (has links)
Cariniana legalis Mart. O. Kuntze (Lecidiaceae) is the largest tree of the Atlantic Forest. To contribute to in situ and ex situ genetic conservation programs for the species, herein we investigate the genetic diversity, inbreeding, intrapopulation spatial genetic structure (SGS), mating system and contemporary pollen flow in three fragmented populations of this species. We found 65 adult trees in the Ibicatu population, 22 in MGI, and four in MGII. Seeds were hierarchically sampled among and within fruits directly from the canopy of 15 seed-trees in Ibicatu (n= 40), five seed-trees in MGI (n= 50), and two seed-trees in MGII (n= 100). Thirteen specific microsatellite loci were developed and validated for 51 C. legalis trees. Eleven loci were polymorphic, revealing a maximum of two to 15 alleles per locus. Using the progeny arrays and seed-tree genotypes, we investigated the Mendelian inheritance, genetic linkage and genotypic disequilibrium of seven microsatellite loci specifically isolated for C. legalis and two previously developed heterologous microsatellite loci. No notable deviations from the expected Mendelian segregation, linkage, or genotypic disequilibrium were detected. The average allelic richness in the adult cohort of Ibicatu was 11.65 and 14.29 for MGI-II and for seeds it was 14.18 in Ibicatu and 10.85 in MGI-II; the average observed heterozygosity for adults of Ibicatu was 0.811 and 0.838 for MGI-II and for seeds it was 0.793 in Ibicatu and 0.786 in MGI-II; the average expected heterozygosity for adults of Ibicatu was 0.860 and 0.900 for MGI-II and for seeds it was 0.856 in Ibicatu and 0.853 in MGI-II. The average fixation index was significantly greater than zero for adults and seeds from both populations. Multilocus outcrossing rate ( m t ) in the three populations was significantly lower than unity (1.0), especially in MGII ( m t = 0.830). The rate of mating among relatives was significant when compared to zero only for Ibicatu ( ????0.266) m s t t . Paternity correlation is substantially higher within than among fruits. The average coancestry coefficient ( ??) was higher and variance effective size ( e N ) was lower than expected for halfsib progenies in all three populations. The number of seed-trees necessary for seed collection to obtain progeny arrays with an effective size of 150 was estimated between 54 to 58 seedtrees. The pollen immigration rate was low, especially for the small stands (maximum of 0.4% for MGI), indicating significant genetic isolation of MGI and MGII. The effective pollination radius was also low in MGI (68 m) and MGII (191 m). For MGII, we also found higher levels of selfing (18%) than for Ibicatu (6%) and MGI (6.4%). The substantial genetic isolation of these stands suggest that we can expect an increase in SGS in the future and strategies to increase gene flow and effective population size, such as transplanting individuals among the populations, are desirable for long term in situ conservation. In conclusion, this study produced valuable information for the management of fragmented populations of C. legalis, contributing to breeding programs and providing guidelines for seed collection aimed at conservation and reforestation programs. / Cariniana legalis Mart. O. Kuntze (Lecidiaceae) é a maior árvore da Mata Atlântica. Para contribuir com a conservação in e ex situ nós investigamos a diversidade genética, endogamia, estrutura genética espacial intrapopulacional (EGE), sistema de reprodução e fluxo contemporâneo de pólen em três populações fragmentadas da espécie. Encontrámos 65 árvores adultas na população Ibicatu, 22 em MGI, e quatro em MGII. As sementes foram colhidas e amostradas hierarquicamente entre e dentro de frutos diretamente da copa de 15 árvores matrizes em Ibicatu (n = 40), cinco em MGI (n = 50), e duas em MGII (n = 100). Treze locos microssatélites foram desenvolvidos e validados em 51 indivíduos de C. legalis. Onze deles foram polimórficos, revelando um máximo de dois a 15 alelos por loco. Usando os genótipos das progênies e matrizes, foi investigada a herança mendeliana, ligação genética e desequilíbrio genotípico de sete locos isolados de C. legalis e dois heterólogos. Não foram detectados desvios notáveis da segregação mendeliana, de ligação, ou desequilíbrio genotípico. A riqueza alélica média de adultos de Ibicatu foi 11,65 e 14,29 para MGI-II e para as sementes foi de 14,18 em Ibicatu e 10,85 na MGI-II, a heterozigosidade média observada para adultos em Ibicatu foi 0,811 e 0,838 para MGI-II, para as sementes foi de 0,793 em Ibicatu e 0,786 em MGI-II, a heterozigosidade média esperada para adultos de Ibicatu foi 0,860 e 0,900 para MGI-II, para as sementes foi de 0,856 em Ibicatu e 0,853 em MGI-II. O índice médio de fixação foi significativamente maior do que zero para adultos e sementes de ambas as populações. A taxa de cruzamento Multilocus (? ) nas três populações foi significativamente menor do que a unidade (1,0), especialmente para MGII ( = 0,830). A taxa de acasalamento entre parentes foi significativa apenas para Ibicatu ( . A correleção de paternidade foi substancialmente maior dentro do que entre os frutos. O coeficiente médio de coancestria (?) foi maior e variação de tamanho efetivo (Ne ) foi menor do que o esperado para progênies de meio-irmãos em todas as populações. O número estimado de árvores matrizes necessárias para a coleta de sementes para se obter um tamanho efetivo de 150 foi de 54-58 árvores. A taxa de imigração de pólen foi baixa, especialmente para os fragmentos menores (máximo de 0,4% para MGI), indicando isolamento genético significativo. O raio efetivo de polinização foi baixo em MGI (68 m) e MGII (191 m). Para MGII também encontramos níveis mais elevados de autofecundação (18%) do que para Ibicatu (6%) e MGI (6,4%). O isolamento genético substancial desses estandes sugerem que podemos esperar um aumento na EGE e que estratégias para aumentar o fluxo gênico e tamanho efetivo da população, como o transplante de indivíduos nas populações, são desejáveis para o longo prazo. Em conclusão, este estudo gerou informações valiosas para a gestão de populações fragmentadas de C. legalis, contribuindo para programas de melhoramento e fornecendo orientações para a coleta de sementes destinadas a programas de conservação e reflorestamento.
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Identification automatisée des espèces d'arbres dans des scans laser 3D réalisés en forêt / Automatic recognition of tree species from 3D point clouds of forest plotsOthmani, Ahlem 26 May 2014 (has links)
L’objectif de ces travaux de thèse est la reconnaissance automatique des espèces d’arbres à partir de scans laser terrestres, information indispensable en inventaire forestier. Pour y répondre, nous proposons différentes méthodes de reconnaissance d’espèce basées sur la texture géométrique 3D des écorces.Ces différentes méthodes utilisent la séquence de traitement suivante : une étape de prétraitement, une étape de segmentation, une étape d’extraction des caractéristiques et une dernière étape de classification. Elles sont fondées sur les données 3D ou bien sur des images de profondeur extraites à partir des nuages de points 3D des troncs d’arbres en utilisant une surface de référence.Nous avons étudié et testé différentes approches de segmentation sur des images de profondeur représentant la texture géométrique de l'écorce. Ces approches posent des problèmes de sur-Segmentation et d'introduction de bruit. Pour cette raison, nous proposons une nouvelle approche de segmentation des nuages de points 3D : « Burst Wind Segmentation », inspirée des lignes de partage des eaux. Cette dernière réussit, dans la majorité des cas, à extraire des cicatrices caractéristiques qui sont ensuite comparées à un dictionnaire des cicatrices (« ScarBook ») pour discriminer les espèces d’arbres.Une grande variété de caractéristiques est extraite à partir des régions segmentées par les différentes méthodes proposées. Ces caractéristiques représentent le niveau de rugosité, la forme globale des régions segmentées, la saillance et la courbure du contour, la distribution des points de contour, la distribution de la forme selon différents angles,...Enfin, pour la classification des caractéristiques visuelles, les forêts aléatoires (Random Forest) de Leo Breiman et Adèle Cutler sont utilisées dans une approche à deux étapes : sélection des variables importantes, puis classification croisée avec les variables retenues, seulement.L’écorce de l’arbre change avec l'accroissement en diamètre ; nous avons donc étudié différents critères de variabilité naturelle et nous avons testé nos approches sur une base qui présente cette variabilité. Le taux de bonne classification dépasse 96% dans toutes les approches de segmentation proposées mais les meilleurs résultats sont atteints avec la nouvelle approche de segmentation « Burst Wind Segmentation » étant donné que cette approche réussit mieux à extraire les cicatrices, utilise un dictionnaire de cicatrices et a été évaluée sur une plus grande variété de caractéristiques de forme, de courbure, de saillance et de rugosité. / The objective of the thesis is the automatic recognition of tree species from Terrestrial LiDAR data. This information is essential for forest inventory. As an answer, we propose different recognition methods based on the 3D geometric texture of the bark.These methods use the following processing steps: a preprocessing step, a segmentation step, a feature extraction step and a final classification step. They are based on the 3D data or on depth images built from 3D point clouds of tree trunks using a reference surface.We have investigated and tested several segmentation approaches on depth images representing the geometric texture of the bark. These approaches have the disadvantages of over segmentation and are quite sensitive to noises. For this reason, we propose a new 3D point cloud segmentation approach inspired by the watershed technique that we have called «Burst Wind Segmentation». Our approach succeed in extracting in most cases the characteristic scars that are next compared to those stored in a dictionary («ScarBook») in order to determine the tree species.A large variety of characteristics is extracted from the regions segmented by the different methods proposed. These characteristics are the roughness, the global shape of the segmented regions, the saliency and the curvature of the contour, the distribution of the contour points, the distribution of the shape according to the different orientations.Finally, for the classification of the visual characteristics, the Random Forest method by Leo Breiman and Adèle Cutler is used in a two steps approach: selection of the most important variables and cross classification with the selected variables.The bark of the tree changes with the trunk diameter. We have thus studied different natural variability criteria and we have tested our approaches on a test set that includes this variability. The accuracy rate is over 96% for all the proposed segmentation approaches but the best result is obtained with the «Burst Wind Segmentation» one due to the fact that this approach can better extract the scars, it uses a dictionary of scars for recognition, and it has been evaluated on a greater variety of shapes, curvatures, saliency and roughness.
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GENOMIC PERSPECTIVES ON AMPHIBIAN EVOLUTION ACROSS MULTIPLE PHYLOGENETIC SCALESHime, Paul Michael 01 January 2017 (has links)
Genomes provide windows into the evolutionary histories of species. The recent accessibility of genome-scale data in non-model organisms and the proliferation of powerful statistical models are now providing unprecedented opportunities to uncover evolutionary relationships and to test hypotheses about the processes that generate and maintain biodiversity. This dissertation work reveals shallow-scale species boundaries and population genetic structure in two imperiled groups of salamanders and demonstrates that the number and information content of genomic regions used in species delimitation exert strong effects on the resulting inferences. Genome scans are employed to test hypotheses about the mechanisms of genetic sex determination in cryptobranchid salamanders, suggesting a conserved system of female heterogamety in this group. At much deeper scales, phylogenetic analyses of hundreds of protein-coding genes across all major amphibian lineages are employed to reveal the backbone topology and evolutionary timescales of the amphibian tree of life, suggesting a new set of hypotheses for relationships among extant amphibians. Yet, genomic data on their own are no panacea for the thorniest questions in evolutionary biology, and this work also demonstrates the power of a model testing framework to dissect support for different phylogenetic and population genetic hypotheses across different regions of the genome.
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CLASSIFYING DOMINANT PARKLAND SPECIES IN A WEST AFRICAN AGROFORESTRY LANDSCAPE USING PLEIADES SATELLITE IMAGERYLunn, Simon January 2020 (has links)
As we move towards a digital based society, technology continues to improve. It is important to take advantage of this to inform and facilitate our sustainable development goals in the most cost-effective and time efficient manner. By utilising the best available technologies, not only can time savings be achieved, but scope of works can be dramatically increased, particularly with ecological data collection. This study will focus on collecting ecological data (tree species) using developing modern technologies (satellites) with the aim of reaching classification accuracies comparable with ground truthed (real life) records. The study area is in central Burkina Faso approximately 30km south of the capital and is generally described as an agroforestry parklands area. The region suffers greatly from poverty and many people are heavily dependent on the agricultural sector and subsistence farming. As these agroforestry parklands are so critical to many people’s livelihoods, it is important to assess the natural resources available within them to provide the best food security management for the people. Tree species locations were overlayed on two satellite images acquired during different stages of the annual growing periods in the agroforestry parklands of the study area. From these images, segmentation of individual tree crowns was done manually and used as the reference data for an object-based classification model, which were assessed for the classification accuracies that can be achieved. Three satellite image scenarios were assessed for classification accuracy, including two single image scenarios and a multi-imagery dataset combining both images. Results indicate that combined images perform the best in terms of overall classification accuracies, closely followed by the end of the wet season growing period. The image acquisition from the end of the dry season was quite poor in comparison, having an overall classification accuracy more than 10% lower than the other scenarios. Of the focus species assessed in this study, Azadirachta Indica was the clear loser in terms of the number of correctly classified individuals from each model scenario. All other focus species were relatively well classified achieving close to or above 60% accuracies in the multi-imagery classification scenario.
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Utilisation de microboutures de saule pour prévenir le développement d'espèces indésirablesDesrochers, Valérie 02 1900 (has links)
No description available.
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Soil Chemical and Microbial Properties in a Mixed Stand of Spruce and Birch in the Ore Mountains (Germany)—A Case StudySchua, Karoline, Wende, Stefan, Wagner, Sven, Feger, Karl-Heinz 12 February 2016 (has links)
A major argument for incorporating deciduous tree species in coniferous forest stands is their role in the amelioration and stabilisation of biogeochemical cycles. Current forest management strategies in central Europe aim to increase the area of mixed stands. In order to formulate statements about the ecological effects of mixtures, studies at the stand level are necessary. In a mixed stand of Norway spruce (Picea abies (L.) Karst.) and silver birch (Betula pendula Roth) in the Ore Mountains (Saxony, Germany), the effects of these two tree species on chemical and microbial parameters in the topsoil were studied at one site in the form of a case study. Samples were taken from the O layer and A horizon in areas of the stand influenced by either birch, spruce or a mixture of birch and spruce. The microbial biomass, basal respiration, metabolic quotient, pH-value and the C and N contents and stocks were analysed in the horizons Of, Oh and A. Significantly higher contents of microbial N were observed in the Of and Oh horizons in the birch and in the spruce-birch strata than in the stratum containing only spruce. The same was found with respect to pH-values in the Of horizon and basal respiration in the Oh horizon. Compared to the spruce stratum, in the birch and spruce-birch strata, significantly lower values were found for the contents of organic C and total N in the A horizon. The findings of the case study indicated that single birch trees have significant effects on the chemical and microbial topsoil properties in spruce-dominated stands. Therefore, the admixture of birch in spruce stands may distinctly affect nutrient cycling and may also be relevant for soil carbon sequestration. Further studies of these functional aspects are recommended.
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Listnaté dřeviny ve výuce botaniky na ZŠ / Deciduous Trees in the Teaching of Botany at Primary SchoolTurynová, Kateřina January 2020 (has links)
This diploma thesis is focused on deciduous trees in the teaching of botany at primary school. In the introduction, deciduous trees and their position in curricular documents are characterized. Theoretical-research work further describes selected forms and methods of teaching used in the teaching of deciduous trees, which were found by own observations during practice or by qualitative research by survey conducted in this work. On this basis, a semi-structured interview with three selected science teachers was created. The aim of the survey was to map and compare the teaching of deciduous trees and the collected data, but especially the opinions and attitudes of individual teachers. Of course, each teacher is an individual and the data obtained cannot be perceived as globally valid for all teachers. Only a more in-depth and wider examination would make demonstrating survey results more accurately possible. The aim of the work also was to analyse selected textbooks of science at the 2nd stage of elementary school in terms of the representation of deciduous trees, which are also used by the interviewed teachers. In the practical part, based on the data obtained from the interview, practical activities for teaching of deciduous trees were proposed. The last part of the work consisted of creating a...
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Entwicklung eines Ertragsschätzers für Kurzumtriebsbestände aus PappelHartmann, Kai-Uwe 12 August 2010 (has links)
Bisherige Verfahren zur Ertragsbestimmung von schnellwachsenden Baumarten im Kurzumtrieb sind entweder mit einem hohen Zeit- und Arbeitsaufwand verbunden und/oder haben destruktiven Charakter. Die vorliegende Arbeit beschäftigt sich mit der Entwicklung eines leicht anwendbaren, zerstörungsfreien und übertragbaren Ertragsschätzers für Kurzumtriebsbestände aus Pappel. Grundlage bildet die Standardisierung von Biomassefunktionen auf deren Basis ein standort- und klonunabhängiges Modell hergeleitet wird, das eine hinreichend genaue Schätzung des Biomassevorrates gestattet. Die Untersuchungen zu Grundlagen der Modellentwicklung und der Test verschiedener Modellansätze erfolgen auf der Basis von Korrelations- und Regressionsanalysen, Signifikanztests und Varianzanalysen. Die Prüfung der Schätzgenauigkeit basiert auf fünf Evaluierungskenngrößen. Für die Anwendung des klonunabhängigen, für Alter ≥ 3 Jahre und Bestandesdichten ≤ 25000 N/ha einsetzbaren Ertragsschätzers sind lediglich drei einfach und schnell zu erhebenden Ertragsgrößen (hm, N, dg) notwendig. Innerhalb der Modellgrenzen betragen die relativen maximalen Abweichungen zwischen Real- und Schätzwerten höchstens +/- 40 % und lässt sich der Biomassevorrat mit einer durchschnittlichen Differenz (Bias) von 7,1 % schätzen.
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