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The investigation of stream leaf litter decomposition and the associated anaerobic cellulolytic bacterial populationsPettibone, Gary W. January 1977 (has links)
The microbial Population of stream leaf litter was examined during the fall and winter of 1976 in Bell Creek, Delaware County, Indiana. Nylon-mesh bags containing leaves were placed in the creek and allowed to become colonized by bacteria and fungi. Of special interest was the enumeration and identification of cellulolytic anaerobic bacteria. This study revealed the presence of these bacteria in all sample cases. These bacteria were generally identified as belonging to the genus Clostridium. Two species of cellulolytic pseudomonads were also isolated. Non-cellulolytic bacteria belonging to the genera Flavobacterium and Beijerinckia were isolated. These aerobic organisms may function indirectly in cellulose degradation by removing toxic byproducts or growth limiting factors.
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Production and fate of soluble organic carbon, nitrogen, and phosphorus during forest ecosystem development root versus leaf litter /Uselman, Shauna M. January 2006 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2006. / "August, 2006." Includes bibliographical references. Online version available on the World Wide Web.
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The foliar physiognomic analysis and taphonomy of leaf beds derived from modern Australia rainforest /Greenwood, David Robert. January 1987 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1987. / Typescript. Copies of two papers co-authored by the author, in back cover pocket. Includes bibliographical references (leaves 128-143).
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The influence of inorganic matrices on the decomposition of organic materials /Skene, Trudi Marie. January 1997 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Soil Science, 1997? / Includes bibliographical references (leaves 134-148).
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A stochastic spatial model for the consumption of organic forest soils in a smoldering ground fire /Holt, Benjamin Victor. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 72-74). Also available via Humboldt Digital Scholar.
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Assessing the consequences of ozone depletion on ecosystem function effects of ultraviolet-B radiation on plant biomass, tissue quality and litter decomposition /Cybulski, Walter J. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains ix, 193 p. : ill. Vita. Includes abstract. Includes bibliographical references.
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Produção e decomposição de folhedo em vegetação secundária com a influência do eucalipto na zona ripária /Santos, Glaucia Regina, 1986. January 2016 (has links)
Orientador: Valdemir Antônio Rodrigues / Coorientador: Silvio Fronsini de Barros Ferraz / Banca: Alexandre Vicente Ferraz / Banca: Deivid Lopes Machado / Resumo: A presença de espécies exóticas em ambientes ripários pode influenciar na quantidade e qualidade de folhas que são realocadas no sistema ecológico. Desse modo, o objetivo deste trabalho foi determinar a influência do Eucalyptus saligna Sm. na dinâmica de produção e decomposição de folhas em três zonas ripárias, cujas hipóteses visam verificar se o estresse hídrico, a densidade e área basal do eucalipto afetam a produção de folhedo, e também constatar se a decomposição de folhas senescentes de eucalipto, em meio aquático e terrestre, ocorre mais lentamente do que das folhas nativas. A pesquisa foi realizada em três microbacias denominadas Forquilha, Monjolinho e Tinga, situadas na Estação Experimental de Itatinga, SP. Apresentam respectivamente 0,4%, 1,2% e 11,9% do total de indivíduos de eucalipto. A avaliação transcorreu durante um ano, e as folhas coletadas foram triadas em eucaliptos e nativas. Avaliou-se a entrada de folhedo por meio de coletores terrestres e verticais, distribuídos sistematicamente por ambas as margens dos rios e também sobre o curso d'água. Para maior caracterização do local, o levantamento dos parâmetros da vegetação foi realizado por meio de parcelas 5x10m e mensuradas as espécies com altura > 1,30 m e DAP ≥ 3,5 cm. Para o estudo de decomposição aquática e terrestre, avaliaram-se um mix de folhas de eucalipto, nativas e eucalipto/nativas (1:1) introduzidas em litter bags. A decomposição em meio aquático foi avaliada ao longo de 112 dias, enquanto que... / Abstract: The presence of exotic species in riparian environments can influence in the quantity and quality of leaves that are relocated in the ecological system. Thus, the aim of this work was to determine the influence of the eucalyptus in the dynamics of production and decomposition of leaves in three riparian zones. The research was done in three micro watersheds named Forquilha, Monjolinho and Tinga located in Estação Experimental de Itatinga in São Paulo. They present respectively 0.4%, 1.2% and 11.9% of the total of eucalyptus individuals. The data collection occurred in a year, and the collected leaves were sorted in eucalyptus and native. The leaf-litter were collected through terrestrial and vertical collectors, systematically distributed on both banks and on the watercourse. For greater characterization of the site, the vegetation parameters were surveyed through 5x10m parcels. For decomposition study, it was evaluated the decomposition of eucalyptus, native and eucalyptus/native (1:1) introduced in litter bags. The decomposition in aquatic environment was evaluated for 112 days, and terrestrial decomposition in 3, 6, 9 and 12 months. The vegetal reminiscent of Tinga watershed showed a higher density (individuals number/ha) and basal area (m²/ha) of eucalyptus. The Forquilha vegetation showed the highest H (Shannon) and J (Pielou) values. In general, leaf-litter decomposition was higher in the end of the dry period. Except for the Monjolinho watershed in the aquatic environment, the eucalyptus leaves had a lower decomposition rate. The eucalyptus leaves, mainly in Tinga and Forquilha watersheds, showed higher quantities of lignin, cellulose, high ratio C/N, low concentration of N and Ca. The forestry fragment of the three watersheds showed significant differences in eucalyptus and native leaves production, where Tinga micro watershed outstanded with the higher eucalyptus deposition. It can ... / Mestre
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Hyphomycetes decaying the litter of Thuja plicata DonnDunn, Michael Thomas January 1980 (has links)
The present study was undertaken to examine the litter decay fungi of red cedar (Thuja piicata Donn). The fungi involved in conifer litter decay have not been examined intensively and there has been no study of red cedar litter decay. Since Thuja is often found in wet, poorly drained areas, it provided an opportunity to observe occurrence of litter decay fungi relative to slight differences in distance from a stream margin. This was determined by observing changes in the frequency of the fungi at various distances from the margin of a stream and also by observing seasonal changes in fungal populations. An ordination of the data was performed to determine if there were species associations which would characterize the relatively minor horizontal and vertical spatial changes in the sites.
The sites were divided into subsites (high, middle and low with respect to the stream) and samples were taken at each subsite. Red cedar branchlets from the L and F litter layers were washed and plated on a selective medium or placed in moist chambers; all observed species were isolated and identified. Most of these were members of the Fungi Imperfecti.
The frequency of occurrence of the more commonly isolated species was utilized in a Principal Components Analysis (PCA) to determine associations of subsites, layers or species. There was little distinction between the three subsites, but there was a general separation of the high subsite from the low subsite, the middle subsite showing affinities to both. The L and F layers
represented a division of the litter layer which formed more distinct clusters in the ordination, especially in the Site B data. Seasonal distinction among the samples seemed to reflect the extremes of the seasons. The spring and summer samples generally grouped together, as did the fall and winter samples. Species associations reflected various combinations of the above groupings, depending on the species groups involved. Again the most distinct groups represented extremes, e.g., species prominent in dry samples, especially in the high subsite, or species prominent in moist conditions, especially in the low subsite.
No single variable provided clear distinction among the various subsites, layers, seasons or species. However, the combination of all of these gave general indications as to probable fungal associations. / Science, Faculty of / Botany, Department of / Graduate
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Nutrient dynamics of the forest floor in an Appalachian oak forest stand following clearcutting and whole-tree removalJohnson, James E. January 1981 (has links)
Experiments were conducted to monitor nutrient dynamics in the forest floor of an upland Appalachian oak forest stands following clearcutting and whole-tree removal. Samples from the L, F, H, and A₁ layers were collected during June, August, and November of 1979 and 1980. Monthly litterfall was collected from October, 1979, through October, 1980. Soil solution samples were extracted on a biweekly basis from April, 1980, through March, 1981, and concurrent soil moisture and temperature determinations were made. All samples were collected from the clearcut area and an adjacent uncut area. Nutrient analyses included total N, P, K, Ca, and Mg, and pH, NH₄-N, and NO₃-N for the soil solutions only.
Comparisons were made between nutrient contents in the forest floor and mineral soil from the clearcut and uncut areas, between nutrient contents within forest floor layers within each area, and between nutrient contents collected over time within each area. Similar comparisons were made using litterfall nutrient contents and soil solution nutrient concentrations. Immediate clearcutting effects were most pronounced on the L layer of the forest floor, due to the logging slash input. Immediately after cutting the L layer in the cut area had a dry weight over 9,500 times that of the L layer in the uncut area. This logging slash rapidly became incorporated into the forest floor of the cut area, and after 15 months, the cut area had a forest floor slightly higher in dry weight and nutrient content than did the uncut area. Slash inputs accounted for these increases, since over the course of the study the cut area received only 14% of the litterfall that occurred in the uncut area. Soil temperature, moisture, and soil solution NH₄-N concentrations were all higher in the clearcut area. Soil solution NO₃-N concentrations were variable but generally the same in both areas. After 15 months following clearcutting and whole-tree removal, the forest floor in the clearcut area was slightly higher in dry weight and nutrient content than an adjacent uncut area, and no site degradation was noted. / Ph. D.
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Some aspects of litterfall and decomposition: fuel accumulation in two plant stands in Taipo Kau forest reserve,New Territories, Hong KongMak, Hon-tak., 麥漢德. January 1978 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
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