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This dissertation examined the participation of eight lower-achieving readers in two intermediate-level elementary classrooms (one fourth- and one fifth-grade) during group discussions about literary texts. The purpose of the investigation was to determine the extent to which lower-achieving readers (defined as students who had persistent struggles to attain minimum scores on state, district, and classroom assessments in reading) displayed discourse features that indicated the students' high-level thinking during heterogeneous and homogeneous (by reading level) discussions about literary texts. Several characteristics of discourse indicate high-level thinking, including but not limited to: generalizations, analyses, speculations, affective responses, inter-textual connections, and elaborated explanations. A secondary purpose was to describe what happened when lower-achieving readers, their peers, and teachers engaged in group discussions about text. / A multiple case study design was used in this investigation. Data were collected between October 2005 and May 2006. Data sources included: field notes collected from participant observation, transcripts and indices of student and teacher interviews, transcripts and indices of audiotaped and videotaped discussions and reading lessons, and students' writing assignments and other artifacts. Multiple strategies were used to analyze the data, including analytic induction and descriptive statistical techniques. A discourse analysis coding scheme was used to determine the extent to which lower-achieving readers likely used high-level thinking about literary texts during group discussions. / The findings revealed focal students used the discourse of discussion as a tool to comprehend text in two ways. The students used the discourse about texts as intellectual scaffolds for their own thinking and transformation in understanding of the texts. In addition, the discussions created authentic opportunities for students to explore reading comprehension strategies (e.g., meanings of new words, visualizing the story). This means students drew on their knowledge of comprehension strategies and incorporated them into their discussions to reason about the texts without explicit instruction from the teacher. Focal students both evoked and heard others refer to and talk about the comprehension strategies during discussions. Moreover, an important contextual foundation of the discussions that seemed to relate to the focal students' thoughtful responses, or those that suggested the students went beyond recalling the literal details of the stories, was the use of the discourse to problem-solve about the meaning of the texts. Finally, in respect to the students' writing assignments that often followed the discussions about the texts, lower-achieving readers made use of the ideas of the discussions in their writing. / Regarding high-level thinking during discussions, the lower-achieving readers' discourse suggested that they thought in high-level ways about texts during discussions, and that they thought in high-level ways to the same extent or nearly the same extent as their peers did in the same discussions about texts. The one major difference in their talk about texts related to the instances of elaborated explanations or instances when students stated a position and explained their thoughts about the position with more than one reason or with evidence from the text. Higher-achieving readers produced significantly more 'elaborated explanations' during discussions than the lower-achieving readers in this study. / From a theoretical perspective, this investigation extends our understanding of lower-achieving readers' use of discursive practices that influence thinking and reasoning about text. From pedagogical perspectives, the findings suggest teachers might need to understand ways to encourage a kind of discourse that elicits genuine problem-solving about the meanings of text. Likewise, teachers might need to understand the discourse features that indicate high-level thinking to model and discuss the features in their work with lower-achieving readers during discussions about literary texts.

Graduation date: 1986

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A two year study examined Root Growth Potential (RGP) in a hydroponic system and Dormancy Release Index (DRI) in one-year-old (1-0) and two-year-old (2-0) eastern white pine (Pinus strobus L.), red pine (Pinus resinosa Ait.), and Scotch pine (Pinus sylvestris L.) seedlings with emphasis on eastern white pine. During 1985-86 all three species of 2-0 stock displayed a similar pattern of RGP with high levels of RGP limited to mid-March. Only 2-0 eastern white pine had a statistically significant relationship between RGP and DRI; however, this relationship was not consistent in 1986-87. The RGP/DRI relationship in 2-0 eastern white pine was strong over both years within a DRI range of 0.22 to 1.00. One-year-old and 2-0 eastern white pine stock had very different patterns of RGP over both years with 1-0 stock maintaining much wider "lifting windows" for high RGP. Cold storage (2C) of 2-0 eastern white pine resulted in variable effects on RGP although it typically progressed dormancy release. There were no strong RGP trends between northern and southern provenances of 1-0 eastern white pine and heritability values indicate that RGP is under minimal genetic control in 1-0 eastern white pine seedlings. Northern and southern provenances did display clear differences in seedling morphology and seasonal patterns of shoot activity. Results of a field outplanting study show that RGP does show promise as a measure of 2-0 eastern white pine seedling quality. The predictive ability of RGP was increased on non-irrigated versus irrigated seedlings. A comparison of greenhouse versus growthroorn RGP testing demonstrated the validity of using greenhouse RGP testing of 2-0 eastern white pine. / M.S.

Thesis (M.Sc. (Horticulture)) -- University of Limpopo, 2017 / Refer to document / National Research Foundation of South Africa, and Agricultural Research Council-Universities Collaboration Centreꞌ for scholarship and research

Dominant understorey species, such as herbs, ferns, palms and shrubs may influence forest tree species diversity and dynamics. Their influence may be through shading the forest floor, thereby affecting regeneration of shade-intolerant species and reducing species diversity, or it may be through competition with seedlings for space and belowground resources, thus modifying or changing the structure of the forest. These effects may be compounded if the life cycle of the understorey species consists of synchronized reproductive and mortality events. This study examines the influence of a dominant understorey species, Isoglossa woodii (Acanthaceae), on regeneration of trees in Indian Ocean subtropical coastal dune forest in southern Africa. The species is a semiwoody herb and has population-wide synchronous reproduction at 4-7 year cycles after which it dies and regenerates from seed. In this thesis I examine three aspects of the ecology of this suppressive herb: (i) the ecological and environmental correlates of the distribution of I. woodii; (ii) the evolutionary advantages of synchronous monocarpy; and (iii) the ecological effects of the extensive cover and putative recruitment window caused by I. woodii on forest tree seedling dynamics and diversity. Isoglossa woodii covered 65–95 % of the understorey, while gaps in this understorey cover occupied the remaining 5–35 % of the area. The spatial distribution of I. woodii was strongly related to tree canopy structure, with the species excluded from sites with dense canopy cover. Woody seedling establishment was inhibited by low light availability ( / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

High output commercial nurseries that cater for the forestry industry are continuously challenged to efficiently and cost effectively produce good quality planting stock to establish large plantations. Currently, South African commercial nurseries produce planting stock in solid compartmentalized trays. One of the major drawbacks of these containers is the susceptibility of trees to root deformation following outplanting, combined with the need for the return of empty containers to the nursery. A potential solution to these challenges is the introduction of wall-less plugs for the production of planting stock. Wall-less plugs are volumes of growing medium, usually cylindrical in shape, devoid of an impenetrable wall in which a plant can grow and establish itself. Such plugs may enable the production of planting stock with improved root systems, without the need for the return of empty containers after outplanting. In this research four prototypes of wall-less plugs were developed, produced on a small scale and tested. These were: 1) Paper-maché plugs made using the original WRIBLOK protocol whereby composted pine bark was bound together with repulped newspaper, 2) Sponge blocks, 3) Hessian bags and 4) Covetan bags. The performance of these prototype wall-less plugs was compared with the performance of four tray types used commercially by the forestry industry: 1) Poly 128 shallow, 2) Poly 98 deep, 3) Unigro 128 and 4) Sappi 49. These are polystyrene and polypropylene-based containers. Of these containers the Unigro 128 and Sappi 49 containers were of similar performance. Performance in terms of height and root collar diameter increase over ten weeks from the time of sowing of the paper-maché plugs was similar to that of the Unigro and Sappi 49 containers. The sponge block, Hessian bags and Covetan bags produced inferior quality planting stock compared to the other treatments tested. Although little progress was made in the ability to describe how one root system differs from another in terms of their branching patterns, a technique was developed to determine root surface area by image analysis software that is freely available. This method may prove useful for further research and for determining seedling quality in commercial nurseries. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Orientador: Durval de Paula Rodrigues Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-09T10:00:40Z (GMT). No. of bitstreams: 1 Padovani_VeraCristinaRamalho_M.pdf: 5126190 bytes, checksum: 92c46be09d3a5c6b107a74a1fbeab24e (MD5) Previous issue date: 2006 / Resumo: Este trabalho tem como objetivo estudar as características físicas e químicas de misturas de diferentes proporções de composto orgânico de lodo de esgoto com casca de arroz carbonizada e avaliar a viabilidade da utilização desses materiais como meio de crescimento para produção de mudas de essências nativas e exóticas. O experimento foi dividido em três fases nas quais foram realizados diversos ensaios. A primeira fase abrangeu a caracterização do lodo de esgoto, do material estruturante e do substrato comercial utilizado no viveiro através de análises químicas. A segunda fase envolveu a realização do processo de compostagem do lodo de esgoto utilizando-se restos de capim e grama cortados, como agente estruturante . Após a compostagem, o lodo de esgoto passou a receber a denominação de COLE ( composto orgânico de lodo de esgoto ) e foi submetido a nova análise química , microbiológica, parasitológica , além da condutividade elétrica. Posteriormente foi misturado com a casca de arroz carbonizada (CAC) nas proporções de 100/00 a 00/100 de COLE/CAC estabelecendo as misturas ou tratamentos que foram submetidos a análises para determinação das propriedades físicas, como macroporosidade, microporosidade, porosidade total , capacidade de retenção de água, densidade aparente . A terceira fase foi dividida em dois ensaios, sendo o primeiro um teste preliminar que utilizou o composto orgânico de lodo de esgoto para a semeadura e cultivo de uma planta indicadora , o tomate, que forneceu resultados que determinaram os tratamentos (substratos) para a instalação do ensaio final , que teve como objetivo o estudo do efeito do substrato na produção de mudas. O segundo ensaio compreendeu a avaliação da produção de essências nativas e exóticas e foi desenvolvido no viveiro municipal da Faculdade Municipal Professor Franco Montoro/Moji Guaçu, onde foram testadas como substrato as proporções 100/00, 90/10,80/20, 70/30, 60/40 (composto orgânico de lodo de esgoto /casca de arroz carbonizada ) utilizando-se tubetes , os quais foram comparados aos substratos testemunhas Plantmax da Eucatex e esterco de curral curtido utilizado pelo viveiro. Foram avaliados parâmetros relativos ao crescimento das mudas: altura de planta (H); diâmetro de colo (D); relação H/D; produção de matéria seca de parte aérea e raiz; relação matéria seca de raiz/matéria seca de parte aérea , área foliar e qualidade de torrão. Os resultados obtidos quanto à caracterização física, microbiológica e química do composto orgânico de lodo de esgoto ( COLE) , indicam que o material está adequado para ser utilizado como meio de propagação de espécies florestais. As mudas de árvores nativas Ingá, Mirindiba rosa e Coração de negro desenvolvidas em substratos contendo composto orgânico de lodo de esgoto ( COLE) / casca de arroz carbonizada (CAC) nas proporções 90/10 e 80/20, apresentaram resultados satisfatórios quando comparados às testemunhas. A espécie exótica Ipê de jardim apresentou bons resultados de crescimento e desenvolvimento das mudas na proporção 90%COLE /10%CAC . Com relação a caracterização nutricional das mudas de Ingá, observou-se que os tratamentos contendo doses de COLE de 70 a 100% apresentaram maior acúmulo de nutrientes nas folhas. A dose de 100% de COLE apresentou resultados superiores em crescimento da parte aérea das mudas, mas insatisfatórios no desenvolvimento das raízes, dificultando a retirada da muda do tubete e interferindo na qualidade final da muda. Com base nos resultados obtidos, conclui-se que o uso do composto orgânico de lodo de esgoto para produção de mudas em tubetes é bastante promissor desde que ele seja utilizado em composição com outro material estruturante , como por exemplo a casca de arroz carbonizada, a fim de se obterem mudas com melhores qualidades fisiológicas e morfológicas / Abstract: This work has as objective to study the physical and chemical characteristics of mixtures of different ratios of organic mixture of sewage with carbonized rice straw and to evaluate the viability of the use of these materials as medium of growth for production of seedlings of native and exotic essences. The experiment was divided in three phases where diverse assays had been carried through. The first phase enclosed the characterization of the sewage sludge, the structural material, and the used commercial substratum in the fishery, through chemical analyses. The second phase involved the accomplishment of the process of composting of the sewage sludge using itself cut remaining portions of grass and gram, as structural agent. After the composting of the sewage sludge to be called COLE ( organic mixture of sewage sludge) and was subdue the new chemical analyses , chemical of microorganism and electric conductivity. Subsequently the sewage sludge and mixes the carbonized rice straw, had been carried through analyses for determination of the physical properties, as macroporosity, microporosity, total porosity, water retention capacity , apparent density and electric conductivity. The third phase was divided in two assays, having been first a preliminary test that used the organic mixture of sewage sludge for the sowing and culture of an indicating plant, the tomato, that it supplied resulted that they had determined the treatments (substratum) for the installation of the final assay, that had as objective the study of the effect of the substratum in the production of seedlings. As the second assay understood the evaluation of the production of native and exotic essences and was developed in the municipal fishery of the Municipal College Professor Franco Montoro /Mogi Guaçu, where ratios had been tested as substratum, 100/00 90/10,80/20, 70/30, 60/40 (organic mixture of sewage sludge/ carbonized rice straw) using tubetes, which had been compared with substrate witnesses Plantmax of the Eucatex and dung of tanned corral used for the fishery. Relative parameters to the growth of the changes had been evaluated: height of plant (h); collar diameter (d); relation H/D; dry matter production of aerial part and root; ratio between dry matter of root and aerial part; leaf area and quality of aggregation of the substratum. The gotten results how much the physical, microbiological and chemical characterization, of the organic mixture of sewage sludge (COLE), indicates that the material is adjusted to be used as half of propagation of forest species. The changes of native trees Ingá, Mirindiba rosa and Coração de negro in substrata I contend organic mixture of sewage sludge (COLE)/ carbonized rice straw (CAC) in ratios 90/10 and 80/20, had presented resulted satisfactory when comparative the witnesses. The exotic species Ipê de jardim presented good results of growth and development of the seedlings in the ratio 90%COLE /10 %CAC. With regard to nutrition characterization of the seedlings of Ingá, it was observed that the treatments I contend doses of organic mixture of sewage sludge (COLE) of 70 the 100%, had presented greater accumulation of nutrients in leaf. The dose of 100% of organic mixture of sewage sludge (COLE) presented resulted superior in growth of the aerial part of the seedlings, but unsatisfactory in the development of the roots, making it difficult the withdrawal of the dumb one of container and intervening with the final quality of the seedling . On the basis of the gotten results, the use of the organic mixture of sewage sludge for production of seedlings in containers is concluded that, is sufficiently promising since that, the same either used in composition with another structural agent , as for example the carbonized rind of rice, in order to get seedlings with better physiological and morphologic qualities / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola

In order to assess the enhancement of seedling survival and growth during drought conditions, five-hundred bare-root seedlings each of Shumard oak (Quercus shumardii Buckl.) and green ash (Fraxinus pennsylvanica Marsh.) were planted each with four soil amendments at a Wildlife Management Area in Lewisville, Texas. The treatments were a mycorrhizal inoculant, mulch fabric, and two superabsorbent gels (TerraSorb® and DRiWATER®). Survival and growth measurements were assessed periodically for two years. Research was conducted on vegetation, soil, and site history for baseline data. Both superabsorbent gels gave significant results for Shumard oak survival, and one increased green ash diameter. For overall growth, significant results were found among DRiWATER®, mycorrhizae, and mulch treatments.