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Oak Savanna Restoration and Management in the Mid-SouthBarrioz, Seth A 01 May 2010 (has links)
Oak savannas are among the most imperiled ecosystems in the United States as a result of habitat degradation and consequently, associated vegetation and wildlife communities have also declined. I evaluated savanna restoration strategies on twelve case studies in Tennessee and Kentucky. These case studies represented a broad range of disturbances and the most advanced savanna restoration sites within the region. I evaluated vegetation and breeding bird responses to landscape and overstory conditions across sites through a meta-analysis. Total grass and forb cover were influenced by overstory metrics but not by topography (P >0.05). Oak regeneration density was influenced by canopy cover, while oak competitor regeneration density was influenced by percent slope and sapling density (P <0.05). With respect to breeding birds, I found forest species persisted within case studies despite substantial disturbance; shrub/scrub birds were common on disturbed sites. Only three obligate grassland bird species, Tyrannus tyrannus, Aimophila aestivalis, Spiza americana, were observed on my sites. Relative abundance of Passerina cyanea was positively related to the groundlayer development; whereas that of Melanerpes erythrocephalus was positively related to basal area of dead trees (P <0.05). Based on my results, canopy reduction and growing-season burns may both be critical for the restoration of savannas within the region.
Drum-chopping is a tool that may expedite oak savanna restoration through improved woody competition control, however, its effectiveness has not been investigated. Therefore, I evaluated drum-chopping effects on vegetative structure at Catoosa Wildlife Management Area, Tennessee, during 2008 and 2009 using two adjacent sites with similar fire and overstory removal histories. One site was subjected to drum-chopping in September of 2007, while an adjacent site (control) was not chopped. Drum-chopping reduced grass and forb cover, and oak seedling density, but increased bare ground and density of vines and shrubs versus the control (P <0.05). Except for bare ground, differences were no longer apparent in the second year. Based on my results, drum chopping may reduce midstory vegetation too thick to be effectively controlled by fire, but otherwise has limited utility as a restoration tool.
Although wildlife managers have tried to restore savannas using prescribed fire and overstory canopy removal, use of other tools may be warranted. One such method is drum-chopping, which has been used elsewhere to reduce woody competition. However, the effectiveness of this method in restoring oak savannas has not been evaluated. Therefore, I evaluated drum-chopping effects on plant composition at Catoosa Wildlife Management Area on the Cumberland Plateau in Tennessee. Two adjacent sites with similar fire and overstory removal histories were selected for this study. One of these sites was subjected to drum-chopping (CHOP) in September of 2007, the adjacent site was not chopped (NOCHOP). Grass cover differed by treatment (P <0.01) and year*treatment (P = 0.03). Forb cover differed by treatment (P <0.01) and legume cover differed by year (P <0.01), treatment (P <0.01), and year*treatment (P = 0.01). Exposed bare ground differed by year (P <0.01) and treatment (P <0.01). Exposed leaf litter differed by year (P <0.01). Vines and shrubs (<1.37m tall) differed by treatment (P <0.01). Oak seedling (0-30.48 cm tall) densities differed by treatment (P = 0.05). Based on my results, drum chopping may be a valuable tool where woody encroachment has become too thick for fire to be effective or herbicides are not a viable option, but otherwise has limited utility as a tool for oak savanna restoration.
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Oak Savanna Restoration and Management in the Mid-SouthBarrioz, Seth A 01 May 2010 (has links)
Oak savannas are among the most imperiled ecosystems in the United States as a result of habitat degradation and consequently, associated vegetation and wildlife communities have also declined. I evaluated savanna restoration strategies on twelve case studies in Tennessee and Kentucky. These case studies represented a broad range of disturbances and the most advanced savanna restoration sites within the region. I evaluated vegetation and breeding bird responses to landscape and overstory conditions across sites through a meta-analysis. Total grass and forb cover were influenced by overstory metrics but not by topography (P >0.05). Oak regeneration density was influenced by canopy cover, while oak competitor regeneration density was influenced by percent slope and sapling density (P <0.05). With respect to breeding birds, I found forest species persisted within case studies despite substantial disturbance; shrub/scrub birds were common on disturbed sites. Only three obligate grassland bird species, Tyrannus tyrannus, Aimophila aestivalis, Spiza americana, were observed on my sites. Relative abundance of Passerina cyanea was positively related to the groundlayer development; whereas that of Melanerpes erythrocephalus was positively related to basal area of dead trees (P <0.05). Based on my results, canopy reduction and growing-season burns may both be critical for the restoration of savannas within the region. Drum-chopping is a tool that may expedite oak savanna restoration through improved woody competition control, however, its effectiveness has not been investigated. Therefore, I evaluated drum-chopping effects on vegetative structure at Catoosa Wildlife Management Area, Tennessee, during 2008 and 2009 using two adjacent sites with similar fire and overstory removal histories. One site was subjected to drum-chopping in September of 2007, while an adjacent site (control) was not chopped. Drum-chopping reduced grass and forb cover, and oak seedling density, but increased bare ground and density of vines and shrubs versus the control (P <0.05). Except for bare ground, differences were no longer apparent in the second year. Based on my results, drum chopping may reduce midstory vegetation too thick to be effectively controlled by fire, but otherwise has limited utility as a restoration tool. Although wildlife managers have tried to restore savannas using prescribed fire and overstory canopy removal, use of other tools may be warranted. One such method is drum-chopping, which has been used elsewhere to reduce woody competition. However, the effectiveness of this method in restoring oak savannas has not been evaluated. Therefore, I evaluated drum-chopping effects on plant composition at Catoosa Wildlife Management Area on the Cumberland Plateau in Tennessee. Two adjacent sites with similar fire and overstory removal histories were selected for this study. One of these sites was subjected to drum-chopping (CHOP) in September of 2007, the adjacent site was not chopped (NOCHOP). Grass cover differed by treatment (P <0.01) and year*treatment (P = 0.03). Forb cover differed by treatment (P <0.01) and legume cover differed by year (P <0.01), treatment (P <0.01), and year*treatment (P = 0.01). Exposed bare ground differed by year (P <0.01) and treatment (P <0.01). Exposed leaf litter differed by year (P <0.01). Vines and shrubs (<1.37m tall) differed by treatment (P <0.01). Oak seedling (0-30.48 cm tall) densities differed by treatment (P = 0.05). Based on my results, drum chopping may be a valuable tool where woody encroachment has become too thick for fire to be effective or herbicides are not a viable option, but otherwise has limited utility as a tool for oak savanna restoration.
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The balance between positive and negative interactions in a savannaBatchelor, Margaret Elizabeth 28 August 2008 (has links)
Not available / text
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Biodiversity of spiders (Araneae) in a savanna ecosystem and the processes that influence their distribution.Whitmore, Cheryl. January 2000 (has links)
I describe the spider biodiversity for a savanna ecosystem, assess sampling techniques,
investigate surrogate measures of species richness and measure the biotic and abiotic
processes affecting spider diversity.
Spiders were sampled at Makalali Game Reserve, Northern Province, South Africa
from February to December 1999 using pitfall traps, sweep netting, beating and active
searching. A total of 4832 individuals from 268 species (14 potentially new), 147 genera (8
endemic and 2 new records for South Africa) and 37 families (1 new record for South Africa)
were recorded.
There was no overall significant difference in spider diversity among different
physiognomic habitat types. However, analysing the results at a functional group level
revealed that the web builders were significantly affected by the habitat type. Mopane
woodland habitat type had the greatest number of web builders and general bushveld the least.
Sweeping and active searching sampled the greatest number of individuals and species
respectively. I recommend a combination of at least beating and active searching, which
together sampled the highest number of unique species, for efficient and cost effective
surveys.
There was a significant relationship between the spider species richness and other
invertebrate richness. However, the relationship is not significant when functional groups are
considered separately. There was also a significant relationship between the number of
species and families and species and genera. However, species level identifications remain
ideal for conservation purposes. Inexperienced participants significantly overestimate the
number of species. The use of surrogates is not supported by the work conducted in this study.
It is still unclear what biotic and abiotic processes or combination of processes
influence spider diversity patterns at the local scale. Different spider functional groups are
significantly influenced by different factors. However, habitat diversity (branches and
vegetation density) was the most common factor influencing spider diversity . Predicted
diversity (modelled using GIS and beta-coefficients from multiple regression analyses) was
higher than measured diversity values. While further research into the role of other
environmental variables is clearly required, current reserve management should aim to
maximise microhabitat structural diversity. / Thesis (M.Sc.)-University of Natal, Durban, 2000.
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Patterns and rate of woody vegetation cluster development in a semi- arid savanna, Natal, South Africa.Le Roux, Izak Gerhardus. January 1996 (has links)
No abstract available. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1996.
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[The] savanna ecosystem : an analysis of plant, soil and water relations in the northern Rupununi savannas of British Guiana as an aid to understanding their nature and originEden, M. J. January 1964 (has links)
Note: / ln May 1962 the McGill University Savanna Research Project wasestablished and has been conducted since that date in the Department ofGeography p McGill University and in the savannas of the Rupununi Di strict pBritish Guiana and the Territorio do Rio Brancop Brazi!.It is generally recognised that although a very wide range of theoryhas been propounded to explain the nature and origin of savannas p no onehas yet brought forward a single convincing viewpoint which has met withuniversal acceptance. One reason for this is that the majority of theoriesextant are based upon inadequate fie ld data with almost a total lack ofexperimental evidence. The McGill Univers ity Sa vanna Research Projectwas set up for the purpose of initiating an experimental and observati onalfield programme which it was hoped would shed light upon the ecologicalrelations of the savanna p and would ultimately enable an explanation to bemade of the nature and distribution of the savanna vegetation of the region .
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Spatial demography of trees in an oak savanna and adjacent dry chert woodland in the Missouri Ozarks /Jenkins, Seán E. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 74-85). Also available on the Internet.
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A case study for Skukuza : estimating biophysical poperties of fires using EOS-MODIS satellite data ; a field and remote sensing study to quantify burnt area and fire effects in South African semi-arid savannas /Landmann, Tobias. January 2004 (has links)
Univ., Diss.--Göttingen, 2003.
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Spatial demography of trees in an oak savanna and adjacent dry chert woodland in the Missouri OzarksJenkins, Seán E. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 74-85). Also available on the Internet.
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Adubação nitrogenada e potássica em socas de cana-de-açúcar com e sem queima em solos de cerrado /Maeda, Alexandra Sanae. January 2009 (has links)
Orientador: Salatiér Buzetti / Banca: Antonio Cesar Bolonhezi / Banca: Marcelo Andreotti / Banca: Takashi Muraoka / Banca: Cassio Hamilton Abreu Junior / Resumo: A adubação representa cerca de 20% dos custos de produção da cana-de-açúcar e entre os nutrientes utilizados, o potássio constitui o elemento mais exigido pela cultura, juntamente com o nitrogênio. O trabalho teve como objetivo estudar os efeitos de doses de nitrogênio e de potássio na produtividade e qualidade das socas de cana-de-açúcar no 3º e 4º ciclos e no 4º ciclo em áreas com palhada (CCP) e sem palhada (CSP) sobre o solo. Os experimentos com os 3º e 4º ciclos foram conduzidos nos anos de 2006 a 2008 com a variedade RB 83-5486 na fazenda Vale da Pecuária, município de Selvíria-MS, e os experimentos com 4º ciclo da cana- de-açúcar em áreas com e sem palhada sobre o solo foram conduzidos nos anos de 2007 a 2008 com variedade RB 86-7515 nas fazendas A Raimundo e Retiro II, respectivamente, no município de Aparecida do Taboado-MS. Todos os experimentos foram desenvolvidos em áreas administradas pela Usina Alcoolvale S/A com quatro doses de nitrogênio (40, 80, 120 e 160 kg ha-1 de N), na forma de uréia, e quatro doses de potássio (40, 80, 120 e 160 kg ha-1 de K2O), na forma de cloreto de potássio, em um esquema fatorial 4x4, totalizando 16 tratamentos dispostos em blocos ao acaso, com quatro repetições. Foram avaliados os teores foliares de macronutrientes nas folhas e nos colmos, açúcares redutores do caldo e da cana, pol do caldo e da cana, pureza do caldo, brix, fibra, produtividade agroindustrial, produção de matéria-seca e produtividade de colmos. Para os experimentos 3º e 4º ciclos da cana-de- açúcar com a variedade RB 83-5486 as doses de N e de K aumentaram os teores de macronutrientes na folha e no colmo. Para os indicadores de qualidade da cana-de-açúcar, houve apenas efeito das doses de N no teor de brix no 3º ciclo, evidenciando que a matéria- prima estava com boa qualidade tecnológica e dentro... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The fertilization represents around 20% of the production cost of sugar-cane crop and potassium constitutes its most demanded nutrient, together with nitrogen. The study had the objective of evaluating the effects of nitrogen and potassium rates on 3th and subsequent 4th cycle of sugar-cane crop (ratoon), and on 4th cycle of this crop in areas with or without cane trash burning, on its productivity and quality. The experiments of 3th and 4th cycles were conducted from 2006 to 2008 with the RB 83-5486 variety at Vale da Pecuária farm, Selvíria- MS, and the experiments with 4th cycle of the sugar-cane in areas managed with (+TB) or without (-TB) cane trash burning were conducted from 2007 to 2008 with variety RB 86-7515 at A Raimundo and Retiro II, respectively, in Aparecida do Taboado-MS. All experiments were carried out in areas administered by Usina Alcoolvale S/A, in a randomized block design using a 4x4 factorial scheme, with four rates of nitrogen (40, 80, 120 and 160 kg ha-1), as urea and four of potassium (40, 80, 120 and 160 kg ha-1 of K2O), as potassium chloride, totalizing 16 treatments with four replicates. The macro and micronutrients content in leaf and stem, reducing sugars, pol, purity, Brix, fiber content, tillering number in 10 meters, agro industrial productivity, dry matter and cane productivity were evaluated. For the experiments of 3th and 4th cycles N and K rates increased the leaf and stem macro and micronutrients contents. For the quality indicators, there was effect of N rates only on Brix in the 3th cycle, observing that the raw material had good technological quality and within the adequate patterns. The K rates increased the agro industrial productivity, dry matter and cane productivity only for the 4th cycle. The cane yield increased linearly with K rates. For the experiments of 4th cycle with RB 86-7515, the N and K rates increased... (Complete abstract click electronic access below) / Doutor
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