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Performance de cruzamentos entre genitores tolerantes à ferrugem asiática da soja / Performance of crosses among parents with tolerance to soybean rustMarcelo Cunha Marques 29 April 2014 (has links)
A ferrugem asiática da soja (FAS) foi constatada pela primeira vez no Brasil em 2000/2001, tendo desde então ocasionado elevados prejuízos aos sojicultores. O emprego de cultivares geneticamente resistentes/tolerantes é um componente fundamental de um programa integrado para controle desta doença. A pesquisa tem encontrado muita dificuldade, pois o fungo Phakopsora pachyrhizi apresenta grande variabilidade patogênica e as poucas fontes de resistência/tolerância disponíveis não são adaptadas às condições brasileiras. O objetivo geral do presente estudo foi avaliar a performance de linhagens experimentais de soja derivadas de cruzamentos entre genitores tolerantes à ferrugem asiática, com a finalidade de incrementar a tolerância a FAS. Os experimentos foram conduzidos durante os anos agrícolas 2008-09, 2009-10 e 2010-11, nas Estações Experimentais Anhumas e Areão e na sede (ESALQ), áreas estas pertencentes à Escola Superior de Agricultura \"Luiz de Queiroz\" e situadas no município de Piracicaba - SP. Os experimentos com as progênies nas gerações F2:4, F2:5 e F2:6 foram delineados em blocos aumentados de Federer, sendo cada experimento subdividido em conjuntos experimentais com testemunhas comuns. Para estimar o efeito ferrugem e o nível de tolerância de cada genótipo a FAS, em cada local e ano agrícola, foram conduzidos dois experimentos com aplicações de fungicidas diferentes: no primeiro experimento aplicou-se fungicida para controle apenas das doenças de final de ciclo (DFC), enquanto que no segundo experimento, foi aplicado fungicida com princípios ativos para o controle tanto das DFC quanto da FAS. Nos experimentos com controle de DFC e FAS houve tendência de médias maiores para PG e PCS. A metodologia do contraste de reações das plantas a fungicidas distintos foi eficiente em estimar o efeito ferrugem e a reação de cada genótipo a FAS. A pressão do fungo da FAS sobre as progênies variou entre os anos agrícolas, tendo sido maior em 2009-10. O local Anhumas destacou-se entre os demais, possibilitando altas médias de produtividade de grãos (PG) em todos os anos agrícolas avaliados. Este ambiente também mostrou-se apropriado para estimar o efeito ferrugem. Os genitores 1 (USP 04-18.032) e 5 (USP 11-38) foram os que originaram as progênies mais precoces e os genitores 3 (USP 97-08.135) e 10 (USP 191-104-11) as progênies mais tardias. Os genitores 8 (USP 191-102-03) e 10 (USP 191-104-11) foram os que mais contribuíram para elevadas médias de PG e peso de cem sementes (PCS). Já o genitor 4 (BUSP 16-015) destacou-se na média de PG, além de ter apresentado valor alto de capacidade média de combinação para PG, na média dos três anos agrícolas. O cruzamento 7x10 (USP 14-06-20 x USP 191-104-11) destacou-se originando o maior número de progênies com desempenho superior em PG e tolerância a FAS. Por outro lado, os genitores 1 (USP 04-18.032), 3 (USP 97-08.135) e 9 (USP 191-103-12) foram os que menos contribuíram para a geração de progênies com alta PG. Houve variação entre as progênies dentro de cruzamentos para as estimativas dos parâmetros de adaptabilidade e estabilidade fenotípica. Consequentemente, as progênies 231- 2224-12 (6x8 = USP 97-10.046 x USP 191-102-03), 231-6127-06 (1x8 = USP 04- 18.032 x USP 191-102-03) e 231-1120-08 (7x10 = USP 14-06-20 x USP 191-104-11) foram as mais indicadas para a seleção recorrente para tolerância a FAS. / The Asian soybean rust (FAS) was reported for the first time in Brazil in 2000/2001 and has since caused considerable damage to soybean crops. The use of genetically resistant cultivars is a key component of an integrated program to control this disease. In the researches has been found many difficulties because the fungus Phakopsora pachyrhizi shows great variability in pathogenicity and the small number of sources of resistance that are available has no adaptability to Brazilian environmental conditions. The overall objective of this study was to evaluate the performance of experimental soybean lines derived from crosses among soybean rust tolerant parents, in order to increase the horizontal resistance (tolerance). The experiments were conducted during the crop years 2008-09, 2009-10 and 2010-11, in three experimental stations (Anhumas, Areão and ESALQ), areas belonging to the College of Agriculture \"Luiz de Queiroz\" and located within the municipality of Piracicaba, State of São Paulo, Brazil. The experiments with progenies in generations F2:4, F2:5 and F2:6 were designed in augmented block of Federer, with each experiment divided into sets with common checks. In order to estimate the effect of FAS and the level of tolerance of each genotype to FAS, in each location and crop year, there was conducted two experiments with applications of different fungicides: in the first experiment was applied one fungicide for controlling only the soybean late season leaf diseases (DFC), while in the second experiment were applied one fungicides with active principles for controlling DFC as well as FAS. In the experiments with control of DFC and FAS there was tendency of superior means for PG and PCS. The methodology of contrasting the plant reactions to different fungicides was effective for estimating the effect of FAS and the level of tolerance of each genotype to FAS. The pressure of the fungal FAS on progenies ranged among crop years, being highest in 2009-10. The location Anhumas stood out among the rest, enabling high average seed yield (PG) in all evaluated crop years; this environment also proved to be suitable for estimating the rust effect. The parents 1 (USP 04-18032) and 5 (USP 11-38) were those that originated the earliest progenies and parents 3 (USP 97-08135) and 10 (USP 191-104-11) the later progenies. The parents 8 (USP 191-102-03) and 10 (USP 191-104-11) were the main contributors to higher average PG and one hundred seed weight (PSC). However, the parent 4 ( BUSP 16-015 ) exceeded for PG, besides also have presented high value of average combining ability for PG, in average of the three crop years. The cross 7x10 (USP 14-06-20 x USP 191-104-11) stood out by originating the highest number of progenies with superior performance in PG and tolerance to FAS. On the other hand, the parents 1 (USP 04-18 032), 3 (USP 97-08 135), and 9 (USP 191-103-12) have contributed with the smallest number of superior progenies in PG. There was variation among progenies within cross, for the estimates of adaptability and phenotypic stability parameters. Consequently, the progenies 231-2224-12 (6x8 = USP 97-10 046 x USP 191-102-03), 231-6127-06 (1x8 = USP 04-18 032 x USP 191- 102-03), and 231-1120 - 08 (7x10 = USP 14-06-20 x USP 191-104-11) were the most suitable for the utilization as parents in the recurrent selection for tolerance to FAS.
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Produção e qualidade de milho-silagem na safra e safrinha, num sistema de integração lavoura-pecuária, em plantio diretoBitencourt Junior, Darcy 29 June 2010 (has links)
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Previous issue date: 2010-06-29 / The first experiment was carried out from May 29, 2006 to June 4, 2008. The objective was to evaluate the yield and agronomic characteristics of corn AS32 for ensiling as affected by early and late planting and the effect of grazing with dairy cows (starting when forage availability was at least 1,500 kg/ha of DM and finishing when residual plant height ranged from 7-10 cm) or mechanical harvesting (no grazing) on winter pasture, grown before corn, in straw in direct planting in an integrated crop-animal system. Experimental design consisted of split-split randomized complete blocks, with three replications. Data were submitted to analysis of variance (factorial 2x2x2 Years x Season x Cutting regimes). Harvesting criterium for corn plants evaluation and ensiling was made at the stage farinaceous hard grain. The second experiment was carried out from May 29, 2006 to June 4, 2008. The objective was to evaluate: (a) silage quality and (b) fermentative parameters, of corn AS32 for ensiling as affected by early and late planting on winter pasture desiccated straw, in direct planting in an integrated crop-animal system. Corn crops were sown in Oct 30, 2006; Nov 16, 2007 and Jan 16, 2007; Feb 06, 2008. Mechanical harvest was made at 15cm residual heights of plants, at the stage of farinaceous hard grain, and finely chopped to 1.5 cm particles size, and ensiled in experimental silos (3.5 kg). The experimental design consisted of completely randomized blocks, with three replications and subplots consisting of planting times (early and late). Data were submitted to analysis of variance, in factorial 2x2 scheme (years x times of plantings) and means compared by Tukey Test (P<0.05). Dry matter yield of normal planting date of corn was higher than for the alternative planting date; grazing, had no effect on dry matter yield . Corn cultivar AS32 recommended haversting stadium (farinaceous hard grain) presented variations in dry matter content of silage according to the year of cropping. Plant components proportions of green matter are different from the standard recommended for high quality corn silage. Fermentative and nutritional parameters showed adequate and acceptable values within the recommended patterns, either for early planting time as for late planting for AS32 hybrid grain corn-silage purpose. Cell wall components (NDF and ADF) showed acceptable values, although ADF remained slightly above of the ideal limit desired for both early and late ensiling of AS32 corn hybrid. / O experimento-1 foi conduzido de 2006 a 2008 na Escola Agrotécnica Federal de Rio do Sul EAFRS Rio do Sul, SC. Foram avaliadas a produtividade e as características agronômicas do milho AS32 para silagem em função da época de semeadura (safra e safrinha) e do pastejo com vacas leiteiras ou corte mecânico em pastagens de inverno. Foi levada em consideração a disponibilidade (1.500 de MS/ha) para entrada dos animais ou o corte e altura residual de 7-10 cm na saída, num sistema de integração lavoura-pecuária em plantio direto na palhada. O delineamento experimental foi de blocos completos ao acaso, com parcelas divididas com três repetições. Os dados foram analisados pelo teste F de análise de variância num esquema fatorial (2x2x2 Anos x Época x Regime de desfolha). O ponto de corte para avaliação das plantas de milho e confecção da silagem foi feito no estádio de grão farináceo duro. O experimento-2 foi conduzido na Escola Agrotécnica Federal de Rio do Sul, SC. Foram avaliadas a qualidade e características nutricionais da silagem do milho AS32 na safra e safrinha num sistema de integração lavoura pecuária (ILP), nos anos agrícolas de 2006/07 e 2007/08. As variáveis respostas foram: (a) parâmetros qualitativos (PB e DIVMS), (b) componentes da parede celular (FDN e FDA) e (c) parâmetros fermentativos da silagem (MS, pH e N-NH3). As lavouras da safra foram estabelecidas com plantio direto em 30/10/06 - 16/11/07 e da safrinha 16/01/07 06/02/08, sobre palhada dessecada de pastagem de inverno (safra), além de espécies espontâneas de verão (safrinha). O corte foi realizado a 15cm do solo, no estádio de grão farináceo duro, ficando as partículas com 1,5cm. Os silos experimentais de Polietileno (capacidade de 3,5kg) foram confeccionados adotando os procedimentos para silos comerciais. O delineamento experimental foi de blocos completos ao acaso com três repetições, com duas parcelas (safra e safrinha). Os tratamentos consistiram de: duas épocas de plantio e dois anos de cultivo. A análise de variância consistiu num fatorial 2x2 (anos x épocas), com Tukey (P<0,05). Resultados: A produção de matéria seca do milho safra foi superior ao da safrinha, não havendo diferença quanto à utilização ou não de pastejo no inverno anterior ao cultivo do milho. A cultivar AS32 no momento indicado para colheita (grão farináceo duro), apresentou variação nos teores de MS da silagem, em função do ano de cultivo. Os parâmetros fermentativos e nutricionais apresentaram valores adequados, dentro dos padrões recomendados, tanto para silagem da safra, como da safrinha. Os componentes da parede celular FDN e FDA apresentaram valores aceitáveis, embora o FDA tenha ficado pouco acima do limite ideal em relação aos padrões desejados, para ambas as épocas de ensilagem.
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The signature of sea surface temperature anomalies on the dynamics of semiarid grassland productivityChen, Maosi, Parton, William J., Del Grosso, Stephen J., Hartman, Melannie D., Day, Ken A., Tucker, Compton J., Derner, Justin D., Knapp, Alan K., Smith, William K., Ojima, Dennis S., Gao, Wei 12 1900 (has links)
We used long-term observations of grassland aboveground net plant production (ANPP, 19392016), growing seasonal advanced very-high-resolution radiometer remote sensing normalized difference vegetation index (NDVI) data (1982-2016), and simulations of actual evapotranspiration (1912-2016) to evaluate the impact of Pacific Decadal Oscillation (PDO) and El Nino-Southern Oscillation (ENSO) sea surface temperature (SST) anomalies on a semiarid grassland in northeastern Colorado. Because ANPP was well correlated (R-2 = 0.58) to cumulative April to July actual evapotranspiration (iAET) and cumulative growing season NDVI (iNDVI) was well correlated to iAET and ANPP (R-2 = 0.62 [quadratic model] and 0.59, respectively), we were able to quantify interactions between the long-duration (15-30 yr) PDO temperature cycles and annual-duration ENSO SST phases on ANPP. We found that during cold-phase PDOs, mean ANPP and iNDVI were lower, and the frequency of low ANPP years (drought years) was much higher, compared to warm-phase PDO years. In addition, ANPP, iNDVI, and iAET were highly variable during the cold-phase PDOs. When NINO-3 (ENSO index) values were negative, there was a higher frequency of droughts and lower frequency of wet years regardless of the PDO phase. PDO and NINO-3 anomalies reinforced each other resulting in a high frequency of above-normal iAET (52%) and low frequency of drought (20%) when both PDO and NINO-3 values were positive and the opposite pattern when both PDO and NINO-3 values were negative (24% frequency of above normal and 48% frequency of drought). Precipitation variability and subsequent ANPP dynamics in this grassland were dampened when PDO and NINO-3 SSTs had opposing signs. Thus, primary signatures of these SSTs in this semiarid grassland are (1) increased interannual variability in ANPP during cold-phase PDOs, (2) drought with low ANPP occurring in almost half of those years with negative values of PDO and NINO-3, and (3) high precipitation and ANPP common in years with positive PDO and NINO-3 values.
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Seleção de linhagens de feijão de ciclo precoce, arquitetura ereta, alta produtividade e cozimento rápido / Selection of common bean lines with early cycle, erect growth, high grain yield and fast cookingSantos, Guilherme Godoy dos 24 February 2014 (has links)
The objectives of this study were to evaluate whether advanced common bean lines differ in phenological, morphological, grain yield and cooking quality characters; to study the linear correlations between these characters; and to select superior lines for these characters for use in breeding programs. For this purpose, 14 common bean lines of trial Use and Cultivation South -Brazilian Bean (VCU - SB) were growing in normal rainy 2012/2013 and in dry season 2013 in Santa Maria, Rio Grande do Sul, Brazil. Data were subjected to analysis of individual and joint variance, using the F test at 5 % probability. If the effect of line and control was significant, the stratification of averages was performed by the Scott-Knott test at 5 % probability. Interaction line x growing season significant was observed for the characters: number of days from emergence to flowering, reproductive period, cycle, lodging, stay green, number of lateral branches, number of pods per plant, number of grains per plant, number of grains per pod, weight of 100 grains, grain yield, grain length and width. The line and control evaluated differed significantly among the characters: number of days from emergence to flowering, cycle, number of nodes on main stem, width and thickness of grains, grain brightness and time of cooking, allowing you to select improved lines for these characters. Positive linear correlation of high magnitude was observed between grain yield and number of pods per plant (r = 0.632) and weight of 100 grains (r = 0.942), while the grain yield and the number of days from emergence to flowering (r = -0.857) and the cycle (r = -0.677) had high negative linear correlation. The LP 09-40 line and BRS Valente control have the lower note of lodging in the two growing seasons, allowing the use of these blocks of crosses to obtain lines with erect architecture. The CNFP 10794 and DF 06-17 lines may be used as parents in hybrid combinations for presenting high yield and reduced cooking time and high yield and early cycle, respectively. / Os objetivos deste trabalho foram avaliar se as linhagens avançadas de feijão diferem quanto aos caracteres fenológicos, morfológicos, de produção e de qualidade de cozimento; estudar as correlações lineares entre esses caracteres; e selecionar linhagens superiores para esses caracteres para uso em programas de melhoramento. Para tanto, foram avaliadas 14 linhagens de feijão do Ensaio de Valor Cultivo e Uso Sul-brasileiro de Feijão (VCU-SB) em cultivo de safra 2012/2013 e de safrinha 2013 em Santa Maria, Rio Grande do Sul, Brasil. Os dados obtidos foram submetidos à análise de variância individual e conjunta, usando o teste F a 5% de probabilidade. Sendo o efeito de linhagens significativo, a estratificação das médias obtidas foi realizada pelo teste de Scott-Knott a 5% de probabilidade. Interação linhagem x época de cultivo significativa foi observada para os caracteres: número de dias da emergência a floração, período reprodutivo, ciclo, acamamento, stay green, número de ramos laterais, número de vagens por planta, número de grãos por planta, número de grãos por vagem, massa de 100 grãos, produtividade de grãos, comprimento e largura de grãos. As linhagens e as testemunhas avaliadas diferiram significativamente para os caracteres: número de dias da emergência a floração, ciclo, número de nós no ramo principal, largura e espessura dos grãos, luminosidade dos grãos e tempo de cozimento dos grãos, possibilitando a seleção de linhagens superiores para esses caracteres. Correlação linear positiva de alta magnitude foi observada entre a produtividade de grãos e o número de vagens por planta (r = 0,632) e a massa de 100 grãos (r = 0,942), enquanto que a produtividade de grãos e o número de dias da emergência a floração (r = -0,857) e o ciclo (r = -0,677), apresentaram alta correlação linear negativa. A linhagem LP 09-40 e a testemunha BRS Valente apresentam as menores notas de acamamento nas duas épocas de cultivo, o que possibilita o uso dessas em blocos de cruzamentos para a obtenção de linhagens com porte ereto. As linhagens CNFP 10794 e DF 06-17 poderão ser utilizadas como genitores em combinações híbridas por apresentarem alta produtividade de grãos e reduzido tempo de cozimento e alta produtividade de grãos e ciclo reduzido, respectivamente.
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Habitat and Seasonal Distribution of the North American River Otter (Lontra canadensis) and Vertebrate Species Assemblages in Two Protected Areas of the Florida EvergladesHamilton, Catherine Faye 01 November 2014 (has links)
The Florida Everglades ecosystem is threatened by human development, increased pollution, freshwater scarcity, and invasive species; factors that have negatively impacted the Everglades and native species health and populations. Man-made canals and levies have redirected the natural flow of fresh water from Lake Okeechobee into the Florida Everglades, starving central and south Florida ecosystems of necessary fresh water and nutrients. Through the efforts of the Comprehensive Everglades Restoration Project (CERP), freshwater is being redirected back into central and south Florida, returning the sheet flow of water back into the Everglades. Monitoring species abundance in the Everglades is a beneficial conservational tool for assessing restoration efforts from CERP. As a semi-aquatic apex predator, river otters (Lontra canadensis) are a useful health bio-indicator for the Florida Everglades. In order to conduct future population studies of river otters in the Florida Everglades, it must first be ascertained where they can be found and what time of year they are most likely to be sighted. For this study, Moultrie infrared game cameras were used to photograph the presence or absence of river otters within the five main habitats in the Everglades; the pinelands, hardwood hammock, cypress swamp, marsh prairie, and mangrove estuary at two protected areas in the Florida Everglades (Big Cypress National Preserve and Fakahatchee Strand State Park). River otters were most frequently sighted in the hardwood hammock habitat, but were also found in the cypress swamp. The large majority of river otter sightings occurred during dry season, which is thought to be a function of restricted water availability and aquatic mobility. Future population studies of river otters would be most productive in the hardwood hammock and cypress swamp habitats during dry season. Game camera images along with field opportunistic sightings, resulted in a variety of species documented. This provided valuable information of species richness and distribution within and amongst the habitats. The hardwood hammock was found to be the most species rich habitat, having over half the species observed in the study in this habitat. The Aves class was the most abundantly observed in the Everglades, and was most frequently sighted during the dry season. As a refuge for migratory birds, the Everglades house the majority of bird species during the winter months, which occur during dry season. The Aves class was most frequently sighted in the pinelands habitat during dry season. This habitat, being the highest in elevation and therefore the driest, shows a stronger resemblance to most northern bird habitats then does the water-saturated wetlands found throughout the Everglades. The mangrove estuary was the most commonly occurring outlier, having the least species overlap when compared to the other habitats. All other habitats in the Everglades are freshwater wetlands, while the mangrove estuary is a brackish environment, which limits the species that are unable to tolerate saline conditions. Further studies of species abundance throughout the Everglades will aid in monitoring CERP restoration efforts over time.
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Změny srážko-odtokového režimu v oblasti Šumavy / Changes of rainfall-runoff regime in the Šumava/Bohemian Forest regionFiala, Ondřej January 2017 (has links)
CHANGES OF RAINFALL-RUNOFF REGIME IN THE ŠUMAVA / BOHEMIAN FOREST REGION Abstract: The goal of this thesis is the evaluation of changes in rainfall-runoff regime in the Šumava region from time and spacial point of view. The thesis includes research and applied part. The research part is dedicated to the methods of evaluation of runoff changes and their possible causes in the Šumava region. In the applied part there is an analysis of precipitaion - runoff regime for long-term time series of average annual and monthly discharges and also annual and monthly precipitations for selected gauging stations in Czech, German and Austrian part of Šumava using absolute and relative homogenity tests and Mann - Kendall test for long-term trend. The results of this thesis showed significant changes in rainfall and runoff seasonality. One of the main aims of this thesis is the identification of possible orographical effect or the difference between windward and leeward part of Šumava. In conclusion the achieved results are evaluated, discussed and compared with subject publications. Key words: absolute homogeneity, land-use, Mann - Kendall test, runoff, basin, discharge, relative homogeneity, season,precipitation, trend, Šumava
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Parental Communication Deviance as a risk factor for thought disorders and schizophrenia spectrum disorders in offspring:The Finnish Adoptive Family StudyRoisko, R. (Riikka) 28 October 2014 (has links)
Abstract
Both genetic and biological and psychosocial environmental risk factors contribute to the aetiology of schizophrenia spectrum disorders. Among the much studied environmental risk indicators are parental Communication Deviance (CD) and the winter or spring birth of a child. Genetic and environmental risk factors do not function in isolation from each other, but gene-environment interactions play a major role in the aetiology of psychotic disorders. The aim of this doctoral thesis is to investigate the role of parental CD as a risk factor (together with other risk indicators) for thought disorders and schizophrenia spectrum disorders in an adoptive child.
A systematised review was performed concerning the association between parental Communication Deviance and schizophrenia spectrum and thought disorders in offspring. A meta-analysis could only be performed for the association of parental CD with schizophrenia spectrum disorders in offspring. A large overall effect size was found (0.79, 95%CI 0.21–1.37). The studies included in the systematised review suggest that frequent parental CD and thought disorders in the offspring are connected with each other.
The two original studies are based on the data derived from the total sample of the Finnish Adoptive Family Study (n=382). First, the association between parental Communication Deviance scored from individual and family Rorschach protocols and the characteristics of the adoptive child and the parents themselves was investigated. The variability of CD in the adoptive parents in individual and family Rorschach situations was most closely associated with the characteristics of the parents themselves. The association of an adoptive child’s thought and schizophrenia spectrum disorders with the child’s genetic risk for schizophrenia spectrum disorders, winter or spring birth, and parental Communication Deviance, and their interactions was also explored. The adoptive child’s thought disorders were associated only with parental CD. None of the risk indicators or their interactions predicted the adoptee’s schizophrenia spectrum diagnosis.
In conclusion, the results indicate that the amount of Communication Deviance is a stable trait of an individual. It may be considered as a risk indicator for schizophrenia spectrum disorders in offspring and, with a lower level of confidence, also for thought disorders in offspring. / Tiivistelmä
Skitsofreniaspektrin sairauksien varsinaisia syytekijöitä ei tunneta, mutta niillä on lukuisia sekä perimään että biologiseen ja psykososiaaliseen ympäristöön liittyviä riskitekijöitä. Nykytietämyksen mukaan riskitekijät eivät vaikuta sairauden syntyyn itsenäisesti, vaan perimän ja ympäristön vuorovaikutuksella on merkittävä osuus. Paljon tutkittuja ympäristöön liittyviä riskitekijöitä ovat lapsen talvi- tai kevätsyntymä ja vanhempien hajanainen kommunikaatio. Tässä väitöskirjassa tutkitaan vanhempien hajanaista kommunikaatiota adoptiolapsen ajatushäiriöiden ja skitsofreniaspektrin sairauksien riskitekijänä.
Vanhempien hajanaisen kommunikaation ja lapsen skitsofreniaspektrin sairauksien ja ajatushäiriöiden yhteydestä laadittiin systemaattinen katsaus. Meta-analyysi voitiin tehdä vain skitsofreniaspektrin sairauksiin liittyen. Vanhempien hajanaisen kommunikaation ja lapsen skitsofreniaspektrin sairauksien välisellä yhteydellä havaittiin olevan suuri efektikoko (0,79, 95 % luottamusväli 0,21–1,37). Katsaukseen sisällytetyt tutkimukset viittaavat siihen, että vanhempien hajanaisella kommunikaatiolla ja lapsen ajatushäiriöillä on myös yhteys.
Väitöskirjan alkuperäistutkimukset perustuvat Suomalaisen adoptiolapsiperhetutkimuksen aineistoon (n= 382). Aluksi tutkittiin vanhempien yksilö- ja perhe-Rorschach-tilanteissa mitatun hajanaisen kommunikaation määrän ja lapsen ja vanhempien ominaisuuksien välistä yhteyttä. Hajanaisen kommunikaation määrän vaihtelu selittyi pääosin vanhempien ominaisuuksilla. Seuraavaksi tutkittiin adoptiolapsen ajatushäiriöiden ja skitsofreniaspektrin sairauksien yhteyttä lapsen skitsofreniaspektrin sairauksille altistavan perimän, talvi- tai kevätsyntymän ja vanhempien hajanaisen kommunikaation kanssa. Huomioon otettiin myös riskitekijöiden yhteisvaikutukset. Mikään riskitekijä tai niiden yhteisvaikutus ei ollut yhteydessä lapsen skitsofreniaspektrin sairauteen. Lapsen ajatushäiriöt olivat yhteydessä ainoastaan vanhempien hajanaiseen kommunikaatioon.
Tutkimuksen tulokset osoittavat, että vanhempien hajanainen kommunikaatio on kohtalaisen muuttumaton piirre, joka on lapsen skitsofreniaspektrin sairauksien riskitekijä. Tulokset viittaavat myös siihen, että vanhempien hajanainen kommunikaatio voi olla lapsen ajatushäiriöiden riskitekijä.
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An evaluation of the impact of acid mine drainage on water quality of the lower Olifants River, South AfricaMohale, Thabang January 2021 (has links)
Thesis (M. Sc. (Geography)) -- University of Limpopo, 2021 / Acid Mine Drainage (AMD) is the acidic water emanating from the mine tailing dams into
the surrounding environment. AMD is regarded as a major environmental threat
associated with mining. The lower Olifants River in the Kruger National Park (KNP) is
considered an environmentally sensitive area, which exhibits high levels of aquatic
ecosystems and supports a variety of terrestrial ecosystems within and around the KNP.
The Phalaborwa mining industries have been discharging the acid mine drainage
contaminated-water into the Ga-Selati River, a tributary to the Olifants River. Although
the impacts in the upper Olifants River catchment have been well documented, it was
the amount of AMD witnessed at KNP and the dying of fish within the lower Olifants
River that raised issues of concerns. Hence, the study investigated the impact of acid
mine drainage on water quality of the lower Olifants River, modelled the distribution of
the dissolved heavy metals in the stream, and evaluated the applied mine wastewater
management strategies at Phalaborwa mining industries.
In this study, water samples were collected seasonally (winter, spring, and summer)
from 2019 to 2020, and the analytical methods and procedures were optimized for the
determination of selected elements in the water samples. During the study, ion
chromatography (IC) was used to detect chloride (Cl), sulphate (SO4
-
), nitrate (NO3),
and fluoride (F), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES)
was used to detect pH, turbidity, electrical conductivity (EC), total dissolved solids
(TDS), magnesium (Mg), manganese (Mn), sodium (Na), potassium (K), aluminium (Al)
and calcium (Ca). Modelling of the distribution of dissolved heavy metals was performed
using the inverse distance weighted (IDW) interpolation technique available in ArcGIS
10.8 software. The range of pH across four sampling sites was between 7.77 and 9.11,
indicating an alkaline pH. The concentration of measured parameters elevated
downstream points with some exceeding the target water quality range (TWQR) for
aquatic ecosystems. The elevated concentration of SO4
-
at sites 3 and 4 (downstream
points) showed that the acid mine drainage is still a matter of concern at the lower
Olifants River catchment. However, the GIS models showed a decreasing trend of the
concentration of heavy metal towards the KNP.
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Hydrogeological characterisation and water supply potential of Lebalelo South, Limpopo Province of South AfricaRambuwani, Rudzani Vincent 08 1900 (has links)
MESHWR / Department of Hydrology and Water Resources / Lebalelo area of Sekhukhune district is one of many areas in South Africa experiencing portable water scarcity, especially during prolonged dry season. Due to the dominance of low yielding aquifers in South Africa, it is essential to manage groundwater resources in these low yielding aquifers. However, the management of low yielding aquifer is difficult in areas like Labelelo where the hydrogeological characteristics of the aquifers are understudied. This study investigated the hydrogeological characteristics of the aquifers in the area using combined geophysical method and analytical groundwater models. Four newly drilled borehole and five existing boreholes were used for this study. Geophysical survey was carried out using magnetic and electromagnetic methods. The magnetic survey was used to locate the position of magnetic bodies such as dolerite dykes and different lithologies with different magnetic properties. The electromagnetic survey however, was used to determine zones of high permeability associated with the intrusive bodies as well as high permeability zones in fault planes. Step test, constant discharge test and recovery tests were conducted on all the boreholes to stress the borehole. This was used to determine a suitable and sustainable pumping rate of the aquifer. Pumping test data from the pumping period and recovery was evaluated and interpreted using AQTESOLVE. Aquifer transmissivity, storativity, internal and external hydraulic boundaries were determined from the data. The transmissivity in the area ranges from 0.08 to 124.7 m2/day. The aquifer types in the area are double porosity aquifer, radial flow aquifer with single porosity. Inductive Coupled Plasma (ICP-MS) was used to measure heavy metals, trace metals and cations while Ion Chromatography (IC) was used to determine anions in groundwater of the study area. The groundwater in the area is dominated by calcium carbonate as a result of long residence time with dolomite. The hydrochemistry of the water indicates that the chemistry of the groundwater in the area is mainly controlled by rock-water interaction. / NRF
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Growth Response of Mixed Native Grass Stands to Simulated Grazing In Mississippi: Forage Yield and Species DynamicsTemu, Vitalis Wilbald 06 August 2011 (has links)
Some native warm-season forage grasses [indiangrass (IG, Sorghastrum nutans), big bluestem (BB, Andropogon gerardii) and little bluestem (LB, Schizachyrium scoparium)] are gaining popularity for improving summer forage production and wildlife habitat in the southeastern USA. Paucity of information about appropriate harvest management limits their restoration success. An experiment was conducted to assess effects of harvest intervals (30-, 40-, 60-, 90 or 120-d) and harvest duration on forage yield and quality, plant growth, sward structure and botanical composition of their mixed stands at Bryan Farms, Clay County, MS. Total season forage was greatest for 30-d and more from first (8472 kg ha-1) than second year plots (7627 kg ha-1). Yield was reduced by up to 43% in the second harvest year. Forage quality (crude protein content and in vitro digestibility) decreased with lengthening of harvest interval and across the harvest season. Tiller weight increased while specific leaf area and relative growth rate decreased with lengthening of harvest interval in first and second year plots. Harvesting reduced sward heights the following May, but treatment did not affect sward heights. Season mean sward heights were shorter for short harvest intervals. Light interception was greatest in the control and decreased with shortening of harvest intervals. Continuous harvesting controlled Solidago canadensis, increased herbaceous forbs, and LB, but decreased IG without substantial effect on BB. Rotational harvesting at 30- or 40-d intervals may improve forage production without compromising breeding cover during recovery. Studies on other management practices including fertilizer application and timing of harvest are needed.
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