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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Biology of Sex Determination and Sexual Development in the Cane Toad (Bufo marinus)

Oganes Abramyan Unknown Date (has links)
To date, the majority of studies into sex determination and sexual development have focused on the mammalian system due to the mouse model being an excellent tool for developmental biology as well as obvious implications to human health and development. However, the focus on the mammalian system has caused a large fraction of other vertebrate groups to be overlooked. The last decade has seen an array of studies into various non-mammalian organisms like fishes, birds, reptiles, and amphibians. These studies have unveiled a remarkably conserved molecular background utilized for sexual differentiation amongst all vertebrates, ranging from the alligator which employs temperature dependent sex determination to the mouse, which employs genotypic sex determination In this project, I implemented molecular methods traditionally used to study model organisms, to investigate an amphibian species, the cane toad (Bufo marinus). The cane toad was chosen due to its invasive status in Australia, as well as being a representative of one of the most successful and specious families of vertebrates, Bufonidae. Since, its introduction, this species has rapidly spread across the continent, adversely effecting native species throughout its introduced range. Recent studies have identified the disruption of the sex-determination pathway as a realistic goal in an otherwise, seemingly futile, effort to curtail their expansion. We decided to approach the study of cane toad sex determination and development on three levels, in order to have a broader understanding of the similarities between toads and other groups, and additionally, to better assess the feasibility of utilizing molecular means to control cane toads in non-native habitats. Firstly, I used a candidate gene approach to clone and characterize five genes which were previously known to be involved in both mammalian as well as amphibian sex determination: Sox9, Dmrt1, p450arom, Sf1, and Dax1. I chose Sox9 and Dmrt1 due to their known involvement in the male-specific pathway of mammals. Dmrt1 was also known to be male specific in other groups, including amphibians. Conversely, I also decided to investigate p450arom and Dax1, due to their affiliation with the female pathway, while Sf1 has a role in both sexes. All of these genes were expressed in the gonads of both sexes of cane toads. However, Sox9 exhibited strong transcriptional up-regulation in testes at the time of sexual differentiation, similar to mammals. Thus, using the candidate gene approach, I was successful in identifying a sex-specific marker which could be utilized in the manipulation of the sex determination pathway (e.g. female to male sex reversal). VIIThe second approach involved the study of sex determination on a cytogenetic level. Traditionally, Bufonids have been assumed to utilize a ZZ/ZW (male homogametic/female heterogametic) sex chromosome system, yet only one recent study has been successful in the identification of sex chromosomes in a toad species. Moreover, the authors identified the sex chromosomes in only one population (of 18 studied), highlighting the scarcity of discernible sex chromosomes in toads. When we began to investigate the karyotype of cane toads, we were able to identify a female-specific length polymorphism in the nucleolus organizer region (NOR) of chromosome 7, making this chromosome pair a strong candidates for the Z and W sex chromosomes. In order to verify our hypothesis, we also performed chromomycin A3 staining to reveal a differential signal between the chromosome pair, indicative of heterochromatin accumulation on the brighter NOR. This study lent strong support to the observed difference between the chromosomes, yet we required further investigation in order to identify the W and the Z chromosomes, specifically. By utilizing comparative genomic hybridization (CGH), I was able to identify a female specific region on the chromosome with the larger NOR, identifying it as the W chromosome. This study was successful in identifying the sex chromosomes in the cane toad. Moreover, it allows us to make a more accurate prediction of the possible sex determination method utilized: either a dosage dependent male determination system, or a female-specific gene in a female determination system. The third approach focused on the Bidder’s organ and its role in sexual development of cane toads. The Bidder’s organ is a gonadal structure comprised of ovary-like tissue, found in both males and females, with no known function. Since our study was focused on female to male sex-reversal of cane toads, we decided to investigate the potential of the Bidder’s organ to interrupt this process. By utilizing the candidate genes, which I had previously cloned, I was able to identify the Bidder’s organ as having an entirely distinct transcriptional pattern in comparison to the gonads of either sex. Additionally, the Bidder’s organ showed significantly higher levels of p450arom expression than the gonads, identifying it as a possible key player in the production of aromatase enzyme for oestrogen production. Moreover, gene expression patterns in the Bidder’s organ strongly correlated with the significant developmental time points in the sexual development of the toads, implying a possible function in the development process of toads. In conclusion, I have performed the first study of the molecular, cytogenetic and anatomical aspects of sexual development in a toad. I was able to verify that cane toads utilize a ZZ/ZW chromosome system and furthermore, likely utilize the mammalian male-linked gene, Sox9, in male development. I was also able to show that the Bidder’s organ is transcriptionally active at key time points, likely indicative of a functional role during development.
52

PRESSURISED ENTRAINED FLOW GASIFICATION OF SUGAR CANE WASTES FOR COGENERATION.

Joyce, James Alexander Unknown Date (has links)
This work has examined the thermochemical conversion of sugar cane processing wastes (bagasse and cane harvesting trash) for use in the design of pressurised entrained flow gasification power cycles (~20 Barg, 600-900oC). The two key parameters of interest were the residual char yield from initial pyrolysis and the heterogeneous reactivity of the char with respect to carbon dioxide. Char yield and gasification rates were measured by a conventional wire mesh reactor and thermogravimetric (TGA) technique, an in-situ sample charring TGA technique and with an entrained flow reactor specifically designed for this work. The new experimental reactor concept is one of the major contributions of the work. Chars from the entrained flow experiments were characterised by optical microscope, SEM/EDS, TEM/EDS and XPS techniques, to help elucidate the processes occurring during pyrolysis and gasification. The key findings and conclusions of the work were as follows: 1. Initial (pyrolysis) char yields were consistent with the data reported in literature for similar materials. Char yields varied with reaction conditions, from 6 to 49 wt% daf for cane trash and 4 to 40 wt% daf for bagasse. Ash content also had a significant effect on char yield. The char yield for both cane trash and bagasse increased in proportion to the logarithm of system pressure. 2. A relatively simple empirical model for char yield under pressurised entrained flow conditions was formulated. This could predict char yields for both the experimental data in this work and those reported in literature for similar biomass materials. While temperature, pressure and ash content were all significant parameters in the model, the primary fitting parameter was a measure of the contribution of secondary char forming reactions and ongoing pyrolysis to char yield. The identification of this parameter is one of the contributions of this work. 3. The measured initial rate of char gasification by carbon dioxide was 0.06 to 1.2 mg per gram of initial char, over the temperature range 750 to 900oC. The rate of gasification was so low as to not contribute significantly to overall fuel conversion in the reaction residence times iv expected of a commercial gasifier. In essence almost all of the experimentally measured fuel conversion could be attributed to pyrolysis, which resulted in 85-95% fuel conversion. 4. Both the raw materials and the residual chars had low surface areas and negligible microporosity. The majority of the measured surface area may have been associated with the ash component rather than the carbonaceous component, which supported the finding of low reactivity. 5. The silica component of the chars exhibited crystalline silicate formation by migration of metal species over time periods of minutes. These silicates displayed signs of sintering, but otherwise remained physically intact; leaving a characteristic skeleton that corresponded to the original structure in the raw materials. 6. The gasification rate showed a time dependent decrease in the entrained flow experiments. This was attributed to coke formation on the char surface, followed by carbon trapping in the ash component at high levels of conversion. Both findings are significant contributions from this work, because they highlight key mechanisms that hinder fuel conversion in the proposed gasification concept. The broad coverage achieved in this work has provided an overall picture of how fuel conversion progresses during the pressurised entrained flow gasification of sugar cane wastes. It is recommended that many of the aspects highlighted in this work be examined further, to confirm the findings and to investigate the means to avoid the factors identified in this work as hindering fuel conversion.
53

In durance vile attitudes towards imprisonment in England during the Du Cane regime, 1877-1895 /

Orr, Richard Byron, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
54

Produtividade e qualidade da cana-de-açúcar sob doses de nitrogênio via fertirrigação subsuperficial por gotejamento

Rhein, Andressa Freitas de Lima [UNESP] 21 December 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-21Bitstream added on 2014-06-13T18:40:33Z : No. of bitstreams: 1 rhein_afl_dr_botfca.pdf: 830132 bytes, checksum: b9fe77801a6875319c93d6446f42f09c (MD5) / A cana-de-açúcar, Saccharum spp., destaca-se como uma das melhores opções de fonte de energia renovável, justificando-se como importante cultivo no Brasil e no mundo. A disponibilidade hídrica do solo e a adubação nitrogenada constituemse em importantes fatores que influenciam a produção da cana-de-açúcar. No presente trabalho caracterizou-se os atributos biométricos e fisiológicos, a qualidade tecnológica e a produtividade da cultivar SP80-3280 de cana-de-açúcar sob doses de nitrogênio aplicadas via fertirrigação subsuperficial por gotejamento. Para tanto, foram estabelecidos cinco tratamentos de N-fertilizante, na forma de ureia, (0, 50, 100, 150 e 200 kg N ha-1), com quatro repetições, aplicados via fertirrigação por gotejamento subsuperficial. Aos 38, 121, 208, 291 e 381 dias após o terceiro corte (DAC) foram determinados os atributos biométricos (Altura das Plantas; Diâmetro dos Colmos; Número de Perfilhos; Número de Folhas Verdes e Secas por Colmo) e fisiológicos (Índice SPAD; Máxima Eficiência Fotoquímica do Fotossistema II; Índice de Área Foliar; Conteúdos de Clorofilas a, b e Total (a+b); Razão Clorofila a/b e Conteúdo dos Pigmentos Carotenóides). A determinação dos atributos tecnológicos (Teor de Sacarose; Teor de Sólidos Solúveis; Açúcares Totais Recuperáveis; Teor de Fibra Industrial; Pureza Aparente do Caldo), bem como a Produtividade de Colmos e de Açúcar foi realizada aos 381 DAC. Para os atributos biométricos e fisiológicos o delineamento experimental utilizado foi o de blocos ao acaso, em esquema fatorial 5x5, constituindo-se dos fatores doses de nitrogênio (0, 50, 100, 150 e 200 kg N ha-1) e épocas de avaliação (38, 121, 208, 291 e 381 DAC), com quatro repetições. Para a qualidade tecnológica e a produtividade o delineamento experimental foi em blocos ao acaso... / Sugarcane, Saccharum spp., stands out as one of the best renewable energy source options, justifying its importance as crop in Brazil and in the world. The water availability in the soil and the nitrogen fertilizer are important factors influencing the sugarcane yield. In the present work was characterized the biometric and physiological attributes, technological quality and productivity of the sugarcane cultivar SP80-3280 under nitrogen doses applied via subsurface drip fertigation. To this end, five treatments were established of N-fertilizer in the urea form (0, 50, 100, 150 and 200 kg N ha-1), with four replicates, applied via subsurface drip fertigation. At 38, 121, 208, 291 and 381 days after the third cut (DAC) were determined biometric (Height of Plants; Diameter of Stalk; Number of Tillers; Number of Green and Dead Leaves per Stalk) and physiological attributes (SPAD Index; Maximum Photochemical Efficiency of Photosystem II; Leaf Area Index; Content of Chlorophylls a, b and Total (a+b); Chlorophyll a/b and Content of Carotenoids Pigments). The technological attributes (Sucrose Content; Soluble Solids Content; Total Recoverable Sugar; Industrial Fiber Content; Apparent Purity of Juice), as well as Productivity of Stalk and Sugar was determined at 381 DAC. The experimental design used for the biometric and physiological attributes was randomized blocks in a 5x5 factorial scheme, constituted by nitrogen doses (0, 50, 100, 150 and 200 kg N ha-1) and evaluation times (38, 121, 208, 291 and 381 DAC), with four replicates. The experimental design for the technological quality and productivity was randomized blocks in function of the nitrogen doses, with four replicates. The biometric and physiological attributes, as well as the technological quality, of the sugarcane cultivar SP80-3280 were changed by the application o... (Complete abstract click electronic access below)
55

Aplicação foliar de silício associado ou não a maturadores em cana-de-açúcar

Foltran, Rodrigo [UNESP] 01 July 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-07-01Bitstream added on 2014-06-13T19:40:06Z : No. of bitstreams: 1 foltran_r_dr_botfca.pdf: 1394299 bytes, checksum: a1b9da39dfef0a308b8e763506510fc8 (MD5) / O presente trabalho teve por objetivo avaliar a eficiência da aplicação foliar de silício associado ou não a maturadores químicos em início e final de safra, com diferentes mecanismos de ação, e suas implicações na produtividade, qualidade tecnológica e rebrota da cana-de-açúcar. O presente estudo foi composto por experimento em cana soca. Os experimentos foram instalados e conduzidos em duas áreas com diferentes condições climáticas e tipos de solo, situadas no município de Olímpia/SP, pertencente a Tereos- Petrobrás/Usina Guarani S.A e em Igaraçú do Tietê/SP, pertencente à Raízen Energia S.A/Usina da Barra, por dois anos consecutivos e subdivididos em início de safra, nos anos agrícolas de 2009 e 2010 e final de safra, nos anos agrícolas de 2008 e 2009, totalizando 24 experimentos. O delineamento experimental utilizado foi de blocos casualizados com cinco repetições. Nos dois experimentos em início de safra, foi utilizada a variedades de cana-deaçúcar RB855453 (maturação precoce). Nos experimentos em final de safra foi utilizada a variedade SP80-3280 (maturação média-tardia) na área pertencente a Raízen Energia S.A, e a variedade RB867515 (maturação média-tardia) na área pertencente a Tereos-Petrobrás. Os tratamentos foram constituídos da aplicação de três maturadores químicos (sulfumeturon metil, etil-trinexapac e ethephon) mais a testemunha (maturação natural), associados à aplicação de silício foliar. Para os maturadores químicos, as doses empregadas foram respectivamente: 20 g p.c. ha-1,0,8 L p.c. ha-1 e 0,66 L p.c. ha-1. Quanto à aplicação de silício, cuja fonte foi o silicato de potássio, a dose foi: 1,4 kg ha-1. A aplicação dos tratamentos ocorreu nos meses de março... / This study aimed to evaluate effectiveness of silicon foliar application with or without chemical ripeners in cane productivity and technological analysis changes. This study was consisted in cane ratoon. The experiments were conducted at Guarani mill/Tereos- Petrobras join-stock Company in Olympia, São Paulo State, and Barra mill/Raízen Energy join stock company in Igaraçu do Tietê / São Paulo State, for two consecutive years, subdivided into early and end harvest season, totaling 24 experiments. The experimental design was a randomized block with five replications. In the beginning of harvest season was used RB855453 varieties (early maturing) in both local and in the final harvest season was used SP80-3280 variety (late ripening) in the Raízen Energy Company areas and RB867515 (middle-late ripening) in the Tereos-Petrobrás . The treatments consisted of foliar application of silicon associated with three chemical ripeners (ethyl-trinexapac ethephon and sulfumeturon methyl) over the control. For chemical ripeners, were used: 0.8 L.ha-1, 0.66 L.ha-1 and 20 g.ha-1. The source of silicon was potassium silicate. The spraying occurred in March and October, using equipment pressurized (CO2) emissions. Was evaluated biometric... (Complete abstract click electronic access below)
56

Dinâmica, eficácia e seletividade do diclosulam em condições de cana crua / Effects of sugarcane straw in diclosulam dynamic and effectiveness

Perim, Lucas [UNESP] 07 November 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-11-07Bitstream added on 2015-03-03T12:06:48Z : No. of bitstreams: 1 000813766.pdf: 1607648 bytes, checksum: fe5ce8ee04886939e3d038e4baa90087 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Devido a utilização crescente do herbicida diclosulam no controle de plantas daninhas na cultura de cana-de-açúcar e a necessidade de dados mais aprofundados sobre a dinâmica e eficiência desse herbicida, este trabalho teve como objetivos avaliar a dinâmica do diclosulam aplicado na presença da palha de cana-de-açúcar, assim como o efeito da umidade na palha na dinâmica deste, sua disponibilidade do na solução do solo e a seletividade e eficácia do herbicida diclosulam no controle de plantas daninhas importande na cultura da cana-de-açúcar. No primeiro estudo avaliou-se o efeito de quatro doses do herbicida diclosulam (Produto Comercial - Coact*): 70,5 ; 88,3 ; 105,8 e 126 g i.a ha-1 em diferentes períodos de permanência (0; 1; 7 e 14 DAA) em 10 t.ha-1 de palha de cana-de-açúcar em função das precipitações simuladas de 5; 10; 25; 50 e 100 mm. No segundo estudo avaliou-se o efeito da umidade na palha da cana-de-açúcar, utilizando a dose de 105,8 g i.a ha-1. A palha que recebeu o herbicida, foi previamente submetida a uma chuva de 20mm e na sequência após a aplicação, foram realizadas as lâminas de chuvas no momento da aplicação. No terceiro estudo quantificou-se a disponibilidade do diclosulam na solução do solo, o qual foi instalado em áreas de cana crua no munícipio de Barra Bonita, em solo arenoso com a aplicação realizada em área com palha e área sem palha. Foram realizadas amostragens de solo nas camadas de 0-10, 10-20 e 20-40 cm aos 40, 95 e 140DAA. Nessa mesma área foi realizada o quarto estudo no qual avaliou a seletividade e / Due to increasing use of herbicide diclosulam in sugarcane weed control and the need for further data on the dynamics and efficiency of this herbicide, the objective of this study was to evaluate the dynamics of diclosulam applied in sugarcane straw, as well the effect of straw moisture on the dynamics, the availability of diclosulam in the soil solution and the selectivity and efficacy of weed control. The first study evaluated the effect of four doses of the herbicide diclosulam (Trade name: Coact*): 70,5; 88,3; 105,8 and 126 g a.i. ha-1 in different periods (0, 1, 7, 14 Days After Aplication) at 10 t ha-1 straw of cane sugar on the rain simulated of 5, 10, 25, 50 and 100 mm. The second study evaluated the effect of straw moisture on the dynamics; the dose used was 105.8 g a.i. ha-1 of diclosulam. The 4 straw that received the herbicide was previously subjected to a rain of 20 mm. And following after application, the rainfall simulation were made at the time of application. The third study was evaluated the diclosulam availability in the soil solution was carried out in a green area in Barra Bonita/SP, in sandy soil with held in area with straw and area without straw. Soil samples were collected at 0-10, 10-20 and 20-40 cm at 40, 95 and 140 DAA. In the same area in which the fourth study evaluated the efficacy and selectivity of diclosulam at the control of Cyperus rotundus, Ipomoea grandifolia and Brachiaria plantaginea. To carry out the analysis of dynamic studies and quantification of diclosulam in soil was used an LC-MS / MS system consisting of a Liquid Chromatography High Performance (HPLC). The results concluded that the first 20 mm of rainfall, are critical to leaching diclosulam of sugarcane straw to the soil. The removal of diclosulam in straw is reduced by increasing the interval between the application and the first rain, regardless of the dose used. The application on ...
57

Geoestatística multivariada na delimitação de zonas de manejo na cultura de cana-de-açúcar / Multivariate geostatistics for delineating management zones in a sugarcane

Sartori, Anderson Antonio da Conceição [UNESP] 10 December 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-12-10Bitstream added on 2015-03-03T12:06:46Z : No. of bitstreams: 1 000813699.pdf: 4732439 bytes, checksum: 2c547f2e72b6b246f0b87a9a9adf87a7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / cana-de-açúcar é uma cultura energética importante comercialmente devido a sua alta produtividade em biomassa e devido seu excelente equilíbrio de gases de efeito estufa e o uso eficiente dos recursos energéticos. Portanto, é necessário compreender os fatores relacionados à produtividade da cana-de-açúcar. Agricultura de Precisão (AP) apresenta-se como uma ferramenta para auxiliar o agricultor na determinação das melhores estratégias de gestão a ser adotado, a fim de aumentar a eficiência das atividades agrícolas. AP requer o apoio de tecnologias de informação espacial, para definir zonas específicas de manejo, acessando as variações do solo e das culturas no campo. AP é uma abordagem de sistema, onde podem ser aplicadas técnicas de fusão de dados para ajudar os agricultores no manejo da cultura. A abordagem de fusão de dados permite a delimitação das Zonas de Manejo (ZMs) em mapas estimados em alta resolução que podem ser utilizados para prescrever o manejo em taxas variáveis de aplicação. Portanto, através da fusão dos parâmetros de solo com dados espectrais de sensoriamento remoto, por meio de técnicas de geoestatística multivariada, foi possível obter estimativas confiáveis das propriedades do solo em diferentes escalas espaciais, aumentando a eficácia do manejo em locais específicos na cultura da cana-de-açúcar. A análise geoestatística multivariada foi dividida em duas partes: Primeira parte destinou-se a delimitação de duas zonas homogêneas de manejo ... / The sugarcane is one of the commercially important energy crop due to its high productivity and biomass due to its excellent balance of greenhouse gas emissions and efficient use of energy resources. Therefore, it is necessary to understand factors related to productivity of sugar cane. Precision Agriculture (PA) is presented as a tool to assist farmers in determining best management strategies to be adopted in order to increase the agricultural activities efficiency. PA requires spatial information technologies support, to define specific areas of site management, accessing soil and crops variations in the field. PA is an approach, where data fusion techniques can be applied to help farmers in crop management. The integration process lead to the delineation of management estimates and zone maps in high resolution which can be used to prescribe management in variables application rates. Therefore, by merging the soil parameters with spectral remote sensing data, using geostatistics multivariate, it was possible to obtain reliable estimates of soil properties at different spatial scales, increasing the effectiveness of management in specific locations in sugarcane cultivation. The complex geostatistical multivariate analysis was divided into two parts: First part was aimed at delineation of two homogeneous management zones through physical and chemical characteristics of the soil and spectral radiance data from the Landsat-8. And second part aimed at showing the potential of fusion between soil data and spectral data from Landsat-8 to improve the delineation of homogeneous management. Three Linear Models Coregionalization (LMC) have been developed: one for soil variables, the second for the spectral data and the third for the fusion of soil data and spectral bands. The spatial data set was analyzed by multivariate: cokriging and multicollocated cokriging to produce study variables thematic maps ...
58

CARBON AND NITROGEN CYCLING IN GIANT CANE (ARUNDINARIA GIGANTEA (WALT.) MUHL.) RIPARIAN ECOSYSTEMS

Nelson, Amanda 01 May 2015 (has links)
Large stands of Arundinaria gigantea (Walt.) Muhl., called canebrakes, were vital to wildlife and lowland ecosystem functions and historically covered millions of acres in the southeastern United States. Since European settlement, human disturbance (i.e, clearing for agriculture and fire suppression) has caused giant canebrakes to become critically endangered ecosystems. Increasing evidence suggests the loss of canebrakes has directly impacted riparian ecosystems, resulting in increased soil erosion, poorer water quality, and reduced flood control. Cane's ecological importance has led to an increased interest in canebrake restoration in riparian zones. To examine the role that cane plays in nutrient cycling and to attempt to determine targeted restoration sites, a four phase research strategy was designed to determine physical and chemical properties of existing riparian stands of native giant cane and their associated soils. Phase one was a GIS analysis to determine what geographical features may be used in selecting sites within a landscape suitable for canebrake restoration. First, common physical site characteristics for 140 existing southern Illinois canebrakes were determined. Soil taxonomy and pH were used to represent soil characteristics and percent slope was used as a topographic metric. These factors, combined with digital elevation models and land cover in GIS were used to identify the potential suitability of sites within the watershed for canebrake plantings and general riparian restoration. The following soil characteristics were determined to be associated with giant cane success: percentage of area containing slopes of 3 percent or less, fine to coarse-silty textures, pH of 5.3 - 6.7, effective cation exchange capacity of less than 30 units, available water holding capacity greater than 0.12, bulk density of 1.37 - 1.65 g cm-3, and percent clay of 11 - 55. Eighty-percent of existing giant cane sites were found within these slope and soil characteristics. The total area of potential riparian canebrake landscapes based on these parameters is 13,970 hectares (35,600 acres) within the Cache River watershed. The remaining three phases examined the role that cane plays in nutrient cycling. Phase two determined the pools and cycling of nitrogen and carbon in canebrakes and compared those to nearby agricultural and forested riparian areas. Phase three quantified the N2O and CO2 fluxes from canebrakes and adjacent forested areas. Phase four included methods to quantify nutrient content of leaf litter and live leaves from existing canebrakes to estimate the nutrient use efficiency of cane. Further, a decomposition study was conducted to calculate the decomposition rate of cane leaves and to explore the litter quality attributes of giant cane. The primary purpose of phase two was to compare the effects of perennial riparian vegetation (giant cane and forest) and annual crops on soil quality, nitrogen cycling, and physical properties. This was to determine if any of them have a significant influence on giant cane distribution, while focusing on nitrogen dynamics to help determine why giant cane is a successful riparian buffer species. Five study sites in the Cache River watershed that had cane, agricultural fields (corn-soybean rotation), and forested areas adjacent to one another were selected. Data were collected on soil texture, carbon/nitrogen ratios, bulk density, nitrogen content (as ammonia and nitrate), and net nitrogen mineralization rates. The crop sites had significantly lower soil C:N ratios than both forest and cane (9.8:1 vs. 10.9:1 and 10.7:1, respectively), though all sites had ratios less than 25:1, indicating a tendency toward nitrogen mineralization. Forest soils had significantly higher rates of net mineralization than cane (19.0 μg m-2 day-1 and 6.6 μg m-2 day-1, respectively), with crop not significantly different from either cane or forest (8.0 μg m-2 day-1). Cane had higher levels of soil carbon and nitrogen when compared to forest and crop soils. Cane can be successful in wetter areas than previously thought, implying that the range of conditions that will support cane is broader than previously thought. Overall, there were few identifiable soil controls on giant cane distribution, or those that differentiate long-standing canebrakes from the nearby crop and forest land. For Phase three, nitrous oxide and carbon dioxide emissions were measured monthly for one year in riparian canebrakes and forests in southern Illinois to determine the rates of greenhouse gas (GHG) fluxes in bottomland riparian areas. Carbon dioxide emissions had a strong correlation with soil temperature (p < 0.001, r2= 0.54), but not with soil water content (p > 0.05), and were greater during the warmer months. Nitrous oxide emissions had a correlation with soil water content (p=0.470, r2 = 0.11), but no relation with soil temperature (p > 0.05), nor a difference across time. Vegetation type did not appear to influence GHG fluxes. Riparian CO2 and N2O emission rates were higher than documented cropland emissions, indicating riparian restoration projects to reduce NO3 delivery to streams may affect N2O and CO2 emissions resulting in an ecosystem tradeoff between water quality and air quality. Leaf deposition, N resorption efficiency and proficiency, and decomposition rates were analyzed in riparian stands of Arundinaria gigantea in southern Illinois for the first time in Phase four. Leaf litter was collected from five established canebrakes monthly over one year and a decomposition study was conducted over 72 weeks. Live leaves, freshly senesced leaves, and decomposed leaves were analyzed for carbon and nitrogen content. Leaf litterfall biomass peaked in November at twice the monthly average for all but one site, indicating a resemblance to deciduous leaf fall patterns. Nitrogen and carbon levels decreased 48% and 30%, respectively, between live leaves and 72 weeks decomposed. High soil moisture appeared to slow decomposition rates, perhaps due to the creation of anaerobic conditions. Cane leaves have low resorption proficiency and nutrient use proficiency, suggesting that these riparian canebrakes are not nitrogen limited. These results will help improve our understanding of the role that giant cane plays in a riparian ecosystem and help focus cane restoration efforts in southern Illinois.
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FIRE AND FERTILIZATION EFFECTS ON THE GROWTH AND EXPANSION OF EXISTING NATIVE CANEBRAKES [ARUNDINARIA GIGANTEA (WALT) MUHL] IN SOUTHERN ILLINOIS

Anderson, Margaret Marziye 01 December 2014 (has links)
AN ABSTRACT OF THE THESIS OF MARGARET MARZIYE ANDERSON, for the Masters of Science degree in Forestry, presented on September 12th, at Southern Illinois University Carbondale. FIRE AND FERTILIZATION EFFECTS ON THE GROWTH AND EXPANSION OF EXISTING NATIVE CANEBRAKES [ARUNDINARIA GIGANTEA (WALT) MUHL] IN SOUTHERN ILLINOIS MAJOR PROFESSOR: Dr. Jon Schoonover Giant cane [Arundinaria gigantea (Walt) Muhl.], a native bamboo, is an integral component of bottomland forests in the southeastern United States. Cane occurs as monodominant stands, also known as canebrakes, which historically covered vast areas of land. As a result of land conversion, overgrazing and altered fire regimes, an alarming 98% reduction of canebrakes has occurred. Due to the ecological significance of giant cane as wildlife habitat, a riparian buffer, its role in soil stabilization and potential as woody biomass, restoration interest has increased. Research with planted cane indicated fertilization and burning had interacting effects on cane growth, however in remnant natural stands, the influence of burning and fertilization on canebrake growth and spread is unknown. This study examined the survival and growth response of cane to burning and fertilization in remnant stands to provide guidance for rehabilitation, restoration and management. Four treatment plots were replicated eight times across seven sites in canebrakes growing in riparian zones adjacent to agricultural fields in the Cache River Watershed, Illinois. The four treatments were randomized factorial design of: 1) burning, 2) fertilization, 3) burning/fertilization, or 4) control. Within treatment plots, two interior and three exterior 1-m² subplots were randomly established to measure culm density (stems/ha), height (cm), diameter (mm), and spread (increase in live culm density by the outward movement from interior subplots into exterior subplots) prior to treatment and after one and two growing seasons. Fertilized and fertilized/burned plots were treated in summers of 2011 and 2012 with a half corn rate of nitrogen (56 kg ha-1), phosphorus (22 kg ha-1), and potassium (37 kg ha-1). Prescribed burning took place in March 2012. Data were analyzed using a three way analysis of variance (fire, fertilization and subplot) (α = 0.05). At year 0 (2011), culm density, height and diameter were not significantly different among treatments. By year 2, live culm density in interior plots slightly increased, however density in exterior plots tended to more than double, indicating canebrake expansion over time. Fertilization tended to increase height and had little effect on cane diameter. Research suggests that cane typically increases in both height and diameter simultaneously, suggesting that fertilization only partially provides the resources needed to stimulate growth. Further analysis on fertilization application rates and timing may be necessary to ascertain the efficiency of its role in culm growth and development. Giant cane responded to prescribed burning through a decrease in height and culm diameter. However, fire increased culm density through stimulation of the growth of new culms. In addition, though fire consumed a portion of existing culms, the canebrake emerged vigorously, demonstrating prescribed fire's utility as a tool for land managers to reduce competition and increase canebrake health and expansion.
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Innovative Approaches for Addressing Concentrated Flow in Agricultural Fields

Pease, Jessica Erin 01 December 2013 (has links)
Riparian buffers are a commonly utilized best management practice (BMP) for mitigating non-point source pollution from agricultural fields. This practice is most effective when runoff enters the buffer as sheet flow. However runoff from becomes concentrated and forms concentrated flow paths (CFPs) breaking through the buffer in critical erosional areas. These critical areas can be determined prior to the implementation of a BMP such as a riparian buffer through incorporation of the Revised Universal Soil Loss Equation (RUSLE) with Geographic Information Systems (GIS). This approach utilizes field characteristics with hydrological processes in order to determine the erosion risk areas from observed field data throughout an entire watershed. In order to re-establish a riparian buffer in critical areas managers need a method that can prevent erosion and the loss of top soil. This study evaluates an innovative method, "Buffer in a Bag", used to restore riparian buffer benefits and to prevent further erosion in CFPs. There were three different treatments initiated for this study the first two treatments the "Buffer in a Bag", and Hand-Planted were implemented prior to the broadcasting of switchgrass seed. The final treatment was the Control, which required no planting within the treatment plot. The "Buffer in a Bag" treatment utilized the placement of giant cane rhizomes within burlap bags along the channel of concentrated flow. The hand planted treatment utilized the placement of giant cane rhizomes planted in the agricultural field adjacent to the path of concentrated flow. The presence of these CFPs breaking through riparian buffers has been noted, but the actual significant soil erosion occurring within the CFP and in the adjacent field has yet to be quantified. Through the use of topographical surveys and geostatistical analysis to produce digital elevation models (DEM) of in-field elevation changes the hydrological processes and volumetric difference for CFPs can be determined. The goal was to define the variability and the spatial pattern from the data as a means of providing comparisons between subsequent survey periods over time and space to estimate the difference and movement of sediment within CFPs. The volumetric differences found when comparing the DEMs between survey periods provide a quantifiable method for evaluating the implementation of a treatment, such as the "Buffer in a Bag". Using geostatistical analysis of volumetric difference between the treatment plots determined that that there was no significant difference between the CFP's over the study period. The mean percentage volumetric difference within the treatment plots between "Buffer in a Bag", Hand-Planted, and Control treatments were -2.49%, -3.72%, and -2.37%, respectively. There was overall net erosion across all treatments with the erosion and accumulation being significantly different across the survey periods for all the treatment CFPs. The mean percentage volume loss across treatments and survey periods varied from positive 10% accumulation to negative 15% erosion for overall loss when looking at each individual survey and CFP. The displayed loss of valuable topsoil and continued expansion of these concentrated flow paths emphasis the need for research in further management applications. There needs to be an effective method developed to address the volumetric difference within CFPs forming in these high risk erosion areas. Using a GIS/RUSLE approach to indicate these high risk erosion areas will hopefully facilitate the prevention of the formation of concentrated flow paths prior to the implementation of a BMP, such as riparian buffers.

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