Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-09-22T16:11:38Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) FINAL tese_claudiaOliveira.pdf: 2499079 bytes, checksum: 54f94d0a5fcba5953b1bd591c6f08a1b (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-09-25T20:19:18Z (GMT) No. of bitstreams: 2 FINAL tese_claudiaOliveira.pdf: 2499079 bytes, checksum: 54f94d0a5fcba5953b1bd591c6f08a1b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-25T20:19:18Z (GMT). No. of bitstreams: 2 FINAL tese_claudiaOliveira.pdf: 2499079 bytes, checksum: 54f94d0a5fcba5953b1bd591c6f08a1b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-05-04 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Devido às previsões de mudanças no clima, muitos estudos vêm sendo realizados com objetivo de prever o efeito de estresses abióticos sobre as plantas. O arroz, arrozvermelho e capim-arroz têm sua morfologia, fisiologia, metabolismo e expressão de genes, modificadas por estresses abióticos, sendo que as espécies respondem de forma distinta aos estresses ambientais. Assim, os objetivos da pesquisa foram comparar alterações morfológicas, fisiológicas, bioquímicas e moleculares em plantas de arroz irrigado e plantas daninhas da cultura com via fotossintética C3 e C4, quando estas são submetidas a estresses por déficit hídrico, temperaturas supra ótimas e diferente qualidade de luz; e, avaliar o efeito de níveis de CO2 em biótipos de E. colona com resistência múltipla a herbicidas. Os resultados permitem inferir que o arroz e arroz-vemelho apresentam respostas fisiológicas e moleculares semelhantes quando expostos a déficit hídrico e temperaturas supra ótimas, sendo observado nessas condições de estresse redução na fotossíntese, elevação de danos à biomoléculas e aumento na expressão de genes ligados a proteção à estresses abióticos, em ambas as plantas. Quanto a qualidade de luz, o arroz tem variáveis fisiológicas e de crescimento afetadas positivamente pela luz azul, já a luz vermelha aumenta apenas variáveis de crescimento e o arroz-vermelho apresenta, incremento nas variáveis de crescimento quando exposto a luz azul.Em um cenário de mudanças climáticas com déficit hídrico, temperatura supra ótimas e diferentes qualidades de luz e elvado [CO2] atmosférico o capim-arroz, por ser C4, é ainda mais competitivo com a cultura do arroz, pois ao contrário das plantas C3, praticamente não apresenta mudanças fisiológicas e moleculares e aumenta o crescimento e produtividade em atmosferas com alta [CO2]. Contudo, biótipos de capim-arroz com resistência múltipla a herbicidas, apresentam desvantagens adaptativas em ambientes alta [CO2], em comparação ao biótipo suscetível. / Due to predictions of climate change many studies have been realized to predict the effect of abiotic stresses on plants. Rice, weedy rice and barnyardgrass have their morphology, physiology and gene expression modified by abiotic stress, and these plants respond differently to environmental stress. The objective of the research was to compare morphological, physiological, biochemical and molecular changes in rice plants and wweed of this crop with photosynthetic pathway C3 and C4 when the plants are submitted to stress due water deficit, supra-optimal temperature and different quality of light; and to evaluate the effect of CO2 levels on E. colona biotypes with multiple herbicide resistance. Four studies were realized to meet the objectives, and the results allow to infer that: rice and weedy rice have similar physiological and molecular responses when exposed to water deficit and supra optimal temperatures, elevation demage to biomolecules and incresed in gene expression linked to protection of abiotic stresses, in both plants. As for light quality, rice has physiological and grow variables positively affectd by blue light whereas red light only incresed growth variables, and weedy rice has increase in groth variables where exposed to blue light. In a climate change scenario, the C4 plant, barnyardgrass, is even more competitive with rice, because unlike the C3 plants, it practilly does not present physiological and molecular change when exposed to water deficit, supra-optimal temperature, and different light qualities. Furthemore, barnyardgrass increases growth and productivity in atmospheres with high [CO2], however, biotypes of herbicides-resistant barnyardgrass have fitness cost in high envirinments [CO2] compared to susceptible biotype.

The timing of weed emergence is of major importance for integrated weed management programs. If accurately forecasted, the timing of weed control operations could be optimized, enabling the implementation of more effective control strategies and consequently, the reduction of herbicide use. Little is known about weed emergence in Quebec. Weed emergence in the field results from the breaking of seed dormancy, seed germination and growth of the seedling to the soil surface. The purpose of this study was initially to review the environmental and cultural factors that affect these mechanisms, to determine which factors are mainly responsible for weed emergence in southwestern Quebec and, finally to develop a weed emergence model. This study focused primarily on common lambsquarters (Chenopodium album L.) and barnyardgrass (Echinochloa crus-galli [L.] Beauv.) since they were the most abundant weeds, representing 37 and 22%, respectively, of the total number of annual weeds in the experimental sites. A 3-year study established that the presence of corn did not affect the density and the pattern of emergence of these weeds. A 2-year experiment demonstrated that rainfall and irrigation had no or little influence on the pattern of weed emergence since soil water content was at or greater than field capacity in the spring. In Quebec, temperature was determined to be the most important factor regulating weed germination and emergence, meaning that weed germination is initiated by a minimal temperature in the spring and that this temperature is specific to each species. Thermo-gradient plate experiments established a base temperature for common lambsquarters, redroot pigweed (Amaranthus retroflexus L.), barnyardgrass, and green foxtail (Setaria viridis L.) of 4, 8, 11, 12 +/- 1 C and <3, >16, 12 and 12 +/- 1 C, respectively for seed lots originating from eastern and southwestern Quebec. These results served as a starting point for the calculation of thermal units for the

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第22080号 / 農博第2372号 / 新制||農||1072(附属図書館) / 学位論文||R1||N5234(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 冨永 達, 教授 奥本 裕, 教授 白岩 立彦 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

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En Afrique Sub-Saharienne, les zones humides forment d'importantes zones de pâturages pour bon nombre de pastoralistes. Le régime d'inondation de ces plaines influence leur fonc tionnement et leur productivité. Pour comprendre et maitriser ces régimes, il est donc essentiel d'évaluer l'impact de l'infrastructure hydro-électrique sur les dynamiques d'inondations en aval des barrages. Pourtant, le manque de données disponibles, l'absence de modèles validés et la forte variabilité environnementale rendent cet exercice difficile. Cette thèse contribue à quantifier l'impact du changement des ressources hydriques sur la productivité fourragère des prairies inondables dans le Delta du fleuve Tana, au Kenya. 1/ Les caractéristiques de croissance et la productivité d'une prairie inondable à Echinochloa stagnina (Retz) P. Beauv. ont été déterminées pour différents régimes de fauche, d'irrigation et conditions d'inondations. Ensuite, un modèle de croissance adapté à des Graminées en C4, tropicales et pérennes, de prairies inondables a été développé. Il constitue, à notre connaissance, le premier modèle éco-physiologique adapté à ce type de prairies. 2/ Des processus hydrologiques importants pour le fonctionnement des écosystèmes (étendue, période, durée et fréquence d'inondation) ont été caractérisés grâce à un modèle de bilan hydrologique et à l'utilisation de techniques de télédétection, et cela en dépit de la faible instrumentalisation du bassin, du peu de données topographiques et d'un fort couvert nuageux. 3/ Une analyse préliminaire de l'impact de différents scénarios d'inondations sur la production fourragère a été effectuée en utilisant des indicateurs de services écosystémiques. Cette thèse participe à l'amélioration de nos connaissances des services écosystémiques des zones humides par la construction de modèles et par l'évaluation de scénarios dans une région du monde où ce type de données est rare. / Wetlands are a vital resource for many pastoralists in Sub-Saharan Africa as they provide dry-season grazing zones. As floods are essential for wetland ecosystems, the assessment of water abstraction and hydroelectric infrastructure on downstream flooding dynamics is crucial. Yet, scarce data, environmental variability and the lack of models make this challenging. This research contributes to quantifying the influence of changing water resources on fodder pro- duction of floodplain grasslands in the Tana River Delta, Kenya. 1/ Growth characteristics of floodplain grasslands of Echinochloa stagnina (Retz) P. Beauv. for different flood and manage- ment options were determined and a quantification of their productivity achieved. This kind of data is scarce for floodplain grasslands. A plant growth model adapted to tropical floodplain conditions and perennial C4 grasses was developed, and is the first known physiologically based model for floodplain grasslands. 2/ Hydrological processes of ecological importance (flood extent, timing, duration, frequency) were characterized in a poorly gauged basin using a water-balance model combined with remote-sensing techniques, despite precise knowledge of discharge rates, topography and a high cloud cover. 3/ A preliminary analysis explored different flooding scenarios and their impact on fodder production through the use of simple ecosystem service indicators. This PhD contributes to the repertoire of wetland ecosystem ser- vices by building biophysically based simulation models and exploring possible scenarios in a region of the world and an ecosystem where these type of evaluations are rare.

Degradation of water resources has become one of the most pressing global concerns currently facing mankind. Constructed Wetlands (CWs) represent a concept to combat deterioration of water resources by acting as buffers between wastewater and receiving water bodies. Still, constructing wetlands for the sole purpose of wastewater treatment is a challenging task. To contribute to this research area, the fundamental question raised in this doctorate thesis was: how do factors such as vegetation and residing water movements (hydraulics) influence wastewater treatment in CWs? Also, effects of different data analysis methods for results of CW hydraulics and wastewater treatment were investigated. Research was focused on  phosphorus (P), ammonium-nitrogen (NH4+-N) and solids (TSS) in wastewater and o n P in macrophyte biomass. Studies were performed in pilot-scale free water surface (FWS) CW systems in Kenya (Chemelil) and Sweden (Halmstad) and as computer simulations. Results from the Chemelil CWs demonstrated that meeting effluent concentration standards simultaneously for all water quality parameters in one CW was difficult. Vegetation harvest, and thus nutrient uptake by young growing macrophytes, was important for maintaining low effluents of NH4+-N and P, especially during dry seasons. On the other hand, mature and dense vegetation growing for at least 4 months secured meeting TSS standards. Phosphorus in above-ground green biomass accounted for almost 1/3 of the total P mass removal, demonstrating high potential for P removal through macrophyte harvest in CWs. Also, results suggested that harvest should be species-specific to achieve high P removal by macrophytes and overall acceptable wastewater treatment in CWs. Still, different methods to estimate evapotranspiration (ET) from the Chemelil CWs showed that water balance calculations greatly impacted estimations of wastewater treatment results. Hydraulic tracer studies performed in the Chemelil and Halmstad CWs showed that mature and dense emergent vegetation in CWs could reduce effective treatment volumes (e-values), which emphasized the importance of regulating this type of vegetation. Also, it was shown that hydraulic tracer studies with lithium chloride performed in CWs with dense emergent vegetation had problems with low tracer recoveries. This problem could be reduced by promoting the distribution of incoming tracer solution into the CW using a barrier near the CW inlet pipe. Computer simulation results showed that the choice of tracer data analysis method greatly influenced quantifications of CW hydraulics and pollutant removal. The e-value could be 50% higher and the pollutant removal 13% higher depending upon used method. Moreover, unrealistic evalues (above 100%) in published literature could to some extent be explained by tracer data analysis method. Hence, to obtain more reliable hydraulic data and wastewater treatment results from CWs, more attention should be paid to the choice of tracer data analysis method. / Konstruerade våtmarker representerar ett koncept för möjligheten att nå en hållbar vattenresurshantering genom att agera som ”filter” mellan föroreningskälla och viktiga vattenresurser såsom sjöar och hav. Mycket kunskap saknas däremot om hur man konstruerar våtmarker med en optimal och pålitlig vattenreningskapacitet. Den här avhandlingen undersöker därför hur vegetation och vattnets väg genom våtmarken (hydrauliken) påverkar avloppsvattenrening i våtmarker. Dessutom undersöktes hur valet av dataanalysmetod av insamlad data påverkar resultaten. Studier genomfördes i Kenya och Sverige i experimentvåtmarker (ca. 40-60 m2) och inkluderadedatainsamling av vattenkvalité, hydraulik (spårämnesexperiment) samt biomassa och fosfor i biomassan av två olika våtmarksväxter. Dessutom genomfördes datorsimuleringar. Resultaten från Kenya visade att växtskörd och efterföljande näringsupptag av nyskördade växter var viktig för att uppnå låga utgående koncentrationer av fosfor och ammonium i en tropisk våtmark, speciellt under torrsäsongen. Däremot var en välutvecklad och tät vegetation viktig för reningen av partiklar. Fosfor i grön växtbiomassa representerade cirka 1/3 av våtmarkernas totala fosforrening, vilket påvisade potentialen i att genom skörd ta bort fosfor från avloppsvatten m.h.a. konstruerade våtmarker. Resultaten pekade också på att skörden bör vara art-specifik för att uppnå en hög fosforrening och generellt bra vattenreningsresultat. Dock visade olika beräkningsmetoder att vattenbalansen i en tropisk våtmark markant kan påverka vattenreningsresultaten. Resultaten från spårämnesexperimenten demonstrerade att den effektiva våtmarksvolymen för vattenrening blev mindre vid hög täthet av övervattensväxter. Detta pekade på att regelbunden växtskörd var viktig för att uppnå god vattenrening i våtmarker. Experiment med spårämnet litium visade att man kan få felaktiga resultat p.g.a. att en del spårämne fasthålls på botten i våtmarken om denna har mycket övervattensväxter. Därför bör spridningen av spårämnet i sådana våtmarker underlättas m.h.a. en spridningsbarriär nära inloppsröret. Simuleringar visade också att valet av dataanalysmetod av spårämnesdata starkt kan påverka resultaten och därmed också vår tolkning av en våtmarks hydraulik och reningskapacitet. Den effektiva volymen kunde vara 50% högre och reningseffekten 13% högre beroende på vilken metod som användes. Likaså kan valet av dataanalysmetod ha bidragit till överskattade och orealistiska effektiva volymer (över 100%) i artiklar publicerade de senaste 25 åren. Genom att fokusera mer på valet av dataanalysmetod och t.ex. jämföra resultaten från två olika metoder kan man minimera risken för bristfälliga resultat och därmed felaktiga slutsatser om en våtmarks vattenreningskapacitet.