Avec la mise en place des politiques de conservation des espèces sauvages, l'extension de l'urbanisation et l'accroissement des populations humaines, le contact homme-faune a considérablement augmenté au cours de ces dernières décennies. Par conséquent, le nombre de maladies d'origines zoonotiques a explosé avec six apparitions d'agents infectieux par an, dont 75% sont susceptibles d’être transmises par un vecteur. La plupart de ces maladies n'ayant pas encore de vaccins, les principales méthodes d'évitement sont basées sur les stratégies de lutte anti-vectorielle adaptées à l'écologie et au comportement alimentaire des vecteurs. Au Gabon, particulièrement dans les parcs nationaux, nous avons identifié six espèces de glossines (Glossina palpalis palpalis, G. fuscipes fuscipes, G. fusca congolense, G. pallicera newsteadi, G. caliginea et G tabaniformis) vivant principalement en milieux forestiers, six espèces de stomoxes (Stomoxys calcitrans, S. inornatus, S. niger niger, S. niger bilineatus, S. omega omega et S. transvittatus) inféodées aux milieux ouverts types forêt secondaire, savane et villages. Nous avons également identifié six espèces de tabanides (Ancala sp., Atylotus sp., Chrysops sp., Haematopota sp., Tabanus par et T. taeniola), mais leur distribution n'était pas claire dans les milieux prospectés. Par ailleurs, nous constatons que ces mouches hématophages ont un régime alimentaire très diversifié, comprenant les mammifères terrestres et aquatiques, les reptiles et les oiseaux. Elles se nourrissent à 86% sur la faune, contre seulement 14% sur l'homme. Cependant, dans les milieux anthropisés les repas sanguins d'origine humaine sont très importants, notamment dans les villages (100%) et autour des camps de recherche implantés dans les parcs (24%). Ainsi en l'absence de faune dans le milieu, ces mouches hématophages se nourrissent sur l'homme. Comme 75% des maladies émergentes chez l'homme proviennent de la faune sauvage et que près de ¾ d'entre elles circulent via le sang, elles sont donc susceptibles d’être détectées dans les repas sanguins de mouches hématophages. Cette technique d'échantillonnage non-invasif de la faune sauvage semble être un bon moyen d'identifier les agents infectieux à ADN (plasmodiums et trypanosomes), mais reste encore imprécise pour les agents infectieux à ARN (arbovirus). / The contact between human and wild fauna has considerably increased during these last decades due to the increase of human population size but also to conservation policies. As a consequence, the number of zoonotic diseases soared with a mean of six new infectious diseases per year, 75% of whom being vectorially transmitted. The way to avoid the human contamination by these emergent diseases is based on the efficient vector control resulting from a deep knowledge of the ecology and the feeding behavior of the different vector species. During our work, we have identified and characterized the ecology of 6 tsetse species (Glossina palpalis palpalis, G. fuscipes fuscipes, G. fusca congolense, G. pallicera newsteadi, G. caliginea and G. tabaniformis) that live in forests and 6 stomoxe species (Stomoxys calcitrans, S. inornatus, S. niger niger, S. niger bilineatus, S. omega omega and S. transvittatus) that live in and around (anthropized places) conservation areas. We have also identified 6 tabanid species (Ancala sp., Atylotus sp., Chrysops sp., Haematopota sp., Tabanus par and T. taeniola). The feeding ecology of the tsetse species have been studied through the determination of host extracted from blood meals in the insect caught with molecular techniques. These hematophagous insects had a diversified diet that was constituted of diverse mammal species but also reptiles and birds. The food intake results mostly from wild fauna (86%) and more rarely from humans (14%). However, in anthropised habitats (villages and research’s camps within the parks), the blood intakes from human origin were important, in particular in the villages (100%), suggesting that without wild fauna the flies shift on human host. In the last part of our work, we tried to identify pathogens in the blood samples extracted from the tsetse species in order to test whether these species could be used as living sampling syringe of the wild fauna. This new proposed non-invasive sampling techniques allowed to detect the DNA of various infectious agents (plasmodiums and trypanosomes), but failed to detect the RNA of viruses (arbovirus) suggesting that this approach could be useful but need to be improved.

Les contaminants d’intérêt émergent (CIEs) ont fait l’objet d’un nombre croissant d’études ces dernières années, notamment dans les milieux aquatiques. Il existe cependant certains manques de connaissances concernant leur occurrence et leur distribution dans les systèmes hydrologiques complexes, notamment la distribution verticale à travers différentes masses d’eau. Les variations saisonnières entre conditions estivales et hivernales restent difficiles à établir en raison des conditions météorologiques hivernales rigoureuses au Canada, limitant l’accessibilité des échantillons. Ainsi, ce projet de maîtrise a porté sur l’étude de 90 CIEs, comprenant des pesticides, des produits pharmaceutiques et marqueurs anthropiques, des hormones et des substances perfluorées dans un environnement océanographique, soit l’Estuaire et le Golfe du Saint-Laurent (EGSL). Deux expéditions ont été menées en conditions hivernales (hivers 2019 et 2020) et une en conditions estivales (été 2019). Ces missions ont permis d’évaluer, dans un premier temps, la distribution spatiale des CIEs dans l’eau de surface le long de l’EGSL, puis, dans un second temps, la variation des concentrations de surface associées aux différentes températures, salinités, couvertures de glace, processus de dégradation ou débit du fleuve des saisons. Par ailleurs, un échantillonnage à plusieurs profondeurs durant l’hiver 2020 a permis de dresser un profil vertical des concentrations le long de l’Estuaire et du Golfe du Saint-Laurent. Finalement, la filtration de larges volumes d’eau de surface durant l’hiver 2020 a permis d’évaluer la concentration des CIEs adsorbés sur la matière en suspension (phase particulaire) et conséquemment, le partitionnement entre la phase dissoute et particulaire, influencé par la variation de la salinité et de la quantité de matière en suspension. Les analyses ont été effectuées grâce au développement et à la validation d’une nouvelle méthode multi-résidus impliquant la chromatographie liquide à ultra-haute performance (UHPLC) couplée à la spectrométrie de masse à haute résolution (HRMS). À notre connaissance, il s’agit de la première étude à caractériser divers contaminants émergents dans les eaux de l’Estuaire et du Golfe du Saint-Laurent, particulièrement pendant la période hivernale et à travers la colonne d’eau. / Contaminants of Emerging Concern (CECs) have been increasingly studied since recent years, for instance in aquatic ecosystems. However, there exist significant knowledge gaps regarding their occurrence and distribution in complex hydrological systems, including their vertical distribution in different water bodies. Seasonal variations between summer and winter conditions are also difficult to establish because of the rigorous winter weather conditions in Canada, restricting the accessibility of samples. Thus, this project focused on the study of 90 CECs, including pesticides, pharmaceuticals and anthropogenic markers, hormones, and perfluorinated substances in an oceanographic environment, namely the St. Lawrence Estuary and Gulf (SLEG). Two expeditions were conducted under winter conditions (winters 2019 and 2020) and one under summer conditions (summer 2019). These expeditions first assessed the spatial distribution of CECs along the SLEG and, secondly, the seasonal and annual variations of the concentrations associated with the different temperatures, salinities, ice cover, degradation processes or seasonal river flow. In addition, sampling at multiple depths during the winter of 2020 allowed for documenting the vertical profiles of CECs throughout the SLEG. Finally, the filtration of large volumes of surface water during the winter of 2020 allowed for the evaluation of the CECs adsorbed onto suspended particle matter (SPM) and consequently, the partitioning between dissolved and particulate phases, influenced by salinity and SPM variations. Analyses were performed following the development and validation of a new multi-residue method involving ultra-high performance liquid chromatography (UHPLC) coupled with high-resolution mass spectrometry (HRMS). To the best of our knowledge, this is the first study to report the occurrence of emerging contaminants in the SLEG, especially during the winter season and across the water column.

Le dioxyde de carbone (CO2), le méthane (CH4) et l’oxyde nitreux (N2O) sont trois des principaux gaz à effet de serre (GES) influençant les changements climatiques (IPCC, 2014). La variabilité des concentrations fluviales de ces GES est souvent liée à l’utilisation du territoire, aux caractéristiques internes de la rivière et au régime hydrique. Cependant, peu d’études se sont penchées sur l’influence de ces facteurs sur la dynamique couplée de ces trois gaz au fil des saisons. Pour cette étude, nous avons mesuré les concentrations et flux de CO2, CH4 et N2O le long d’une rivière tempérée : la Rivière du Nord, une fois par saison durant trois années consécutives. Le long du bassin versant de cette rivière la géologie diffère entrainant un changement radical d’utilisation du territoire. De fortes différences saisonnières ont été observées : les concentrations de CO2 et N2O étaient plus élevées en hiver, tandis que celles de CH4 étaient plus importantes l’été. Les sites de confluence majeure avaient les émissions les plus élevées. Les concentrations ont été influencées par l’utilisation des terres, les plus fortes concentrations de tous les GES se trouvant où les activités urbaines et agricoles sont les plus intensives. Cependant, la variabilité spatiale fut minimisée pendant les périodes de fort débit. Bien que l’utilisation du territoire ait influencé la variabilité spatiale des concentrations le long de la rivière, les changements de températures et de régime hydrique provoqués par les saisons ont influencé, respectivement, l’importance relative des gaz et leurs concentrations et émissions globales. / Carbon dioxide (CO2), methane (CH4), and nitrous dioxide (N2O) are three of the main greenhouse gases (GHGs) that influence climate change (IPCC, 2014). Variability in the riverine concentrations of these three GHGs is often related to land use, within river features, and hydrologic regimes. However, few studies have looked at the interacting influence of these factors on the coupled dynamics of these gases across seasons. Here, we measured CO2, CH4, and N2O concentrations and fluxes along a 146.6 km stretch of the main stem of a north temperate river, with a change in geology resulting in a sharp shift in land use once per season for three consecutive years. Strong seasonal differences in gas concentrations were observed: CO2 and N2O were both higher overall during winter but were occasionally undersaturated, whereas summer had the highest concentrations of CH4. Sites of major confluence had the highest emissions, acting as vents. Concentrations were influenced by land use, with the highest concentrations of all gases found in the lower reaches where urban and agricultural activity are most intensive. However, spatial variability was minimized during periods of high flow when the river acted more like a pipe. This suggests that how major gases are coupled is largely a function of differential processes across seasons. Although land use influenced the spatial variability in concentrations along the river, seasonal changes in temperature influenced the relative importance of the gases, and hydrology mediated their overall concentrations and emissions.

Optimizing customer satisfaction is vital to maintain relevance as well as being competitive on a growing market. This research is aimed to explore what aspects of design and functionality that should be prioritized when developing solo tunnel tents for four season use within a European market. Since solo tents are small in size, users seem to prioritize purchasing a tent for two people because it provides bigger space for equipment, accompanied animals and is more reliable in bad weather. To examine the research questions, a design theory and human centered design method has been applied to optimize customer satisfaction. The study consists of literature study, survey, interviews, empathy mapping and prototyping, which resulted in an implemented prototype for a four season solo tent planned for future production. Furthermore, a prototype has been developed by data conducted from the survey, interviews and a design brief given by the partnering company. Conspicuous results have been shown through a survey and interviews, which explains the difficulties in development of tents to ensure a wider range of customer satisfaction. Findings in this research emerged that weight was not the most important aspect when buying a four season solo tent. A correlation has been investigated, there was an expectation from the producer that lightweight tents were preferred by the users, however this research exposed that it is not as important as imagined for a four season solo tent. In the sense of a solo tent for four seasons, the users desire space over weight. Furthermore, the results also showed that there was a difference in requirements related to the two different groups that had been investigated. It was found that experienced users had a higher preference of design and ergonomic aspects compared to the common users that did not rank it as important. Within this research a total of 55 people participated, where 44 people participated in the survey and 11 people participated in the interviews. For future research a larger number of participants, preferably women, could provide an interesting result and more on if people from a larger area outside Sweden participated in the research. Furthermore a physical test of the prototyped tent would ensure that this study results in a design that optimizes customer satisfaction.

This thesis seeks to answer the question of how Joseph Smith—History found in The Pearl of Great Price developed into a part of the canon of The Church of Jesus Christ of Latter-day Saints. When the prophet Joseph Smith first dictated the text to his scribes it seems he had not intended for the work to become scripture, but simply to follow the Lord's divine mandate to keep a record. Additionally he provided the purpose in his document to "disabuse the public mind, and put all inquirers after truth in possession of the facts, as they transpired." The format he proposed for the Manuscript History illustrates how it was originally not purposed for scripture. The compiling of that history took the efforts of many men and women and spanned the length of almost twenty years to complete. Joseph Smith had begun the dictation to his scribe George Robinson in 1838, but it was unfinished. Joseph later began the dictation anew to his scribe James Mulholland, first having the man rewrite what he had told to Robinson and then picking up the dictation from there. While the prophet had started and stopped histories before, this particular dictation began the enduring effort. The Manuscript History was developed from the original 59 pages that were scribed by Mulholland. By the efforts of other scribes, but mostly Willard Richards, the history was completed. The official statement of Brigham Young and Orson Pratt upon its completion said nothing of extracting portions for canon. But Mulholland's work seemed destined for a different purpose than the rest of the Manuscript History. It was printed serially in the Times and Seasons, and a few apostles seemed to catch a vision of what the manuscript could do for potential converts and members of the Church. Orson Pratt was especially a proponent of communicating certain key events as illustrated in his missionary tract "Remarkable Visions." A later apostle, Franklin D. Richards, would see the benefit of using the official history to distribute the history of the restoration of the Church to others. He extracted portions from Mulholland's text that covered certain main events in Joseph's life and printed them in his missionary tract The Pearl of Great Price. This pamphlet would eventually be canonized by The Church of Jesus Christ of Latter-day Saints in 1880. Joseph Smith-History's inclusion in the reclamation of revelation that occurred in 1880 was deserved. This is evidenced by examining the process of canonization and the guiding principles of canonization employed by the Church of Jesus Christ of Latter-day Saints. It was canonized at the same time as many other revelations and at a General Conference saturated with many important events. Consequently it is difficult to gauge the reaction to its inclusion in canon, except in how it has been used since its canonization. After its inclusion into scripture the text has become a foundational piece of literature for the Church. The impact the text has had can be seen in the culture, missionary work, and doctrine of the Church. The focus of this thesis is to map the text's journey from birth to canonization.

Abstract: Road traffic accidents claim more than 1,500 lives each year in Canada and affect society adversely, so transport authorities must reduce their impact. This is a major concern in Quebec, where the traffic-accident risks increase year by year proportionally to provincial population growth. In reality, the occurrence of traffic crashes is rarely random in space-time; they tend to cluster in specific areas such as intersections, ramps, and work zones. Moreover, weather stands out as an environmental risk factor that affects the crash rate. Therefore, traffic-safety engineers need to accurately identify the location and time of traffic accidents. The occurrence of such accidents actually is determined by some important factors, including traffic volume, weather conditions, and geometric design. This study aimed at identifying hotspot locations based on a historical crash data set and spatiotemporal patterns of traffic accidents with a view to improving road safety. This thesis proposes two new methods for identifying hotspot locations on a road network. The first method could be used to identify and rank hotspot locations in cases in which the value of traffic volume is available, while the second method is useful in cases in which the value of traffic volume is not. These methods were examined with three years of traffic-accident data (2011–2013) in Sherbrooke. The first method proposes a two-step integrated approach for identifying traffic-accident hotspots on a road network. The first step included a spatial-analysis method called network kernel-density estimation. The second step involved a network-screening method using the critical crash rate, which is described in the Highway Safety Manual. Once the traffic-accident density had been estimated using the network kernel-density estimation method, the selected potential hotspot locations were then tested with the critical-crash-rate method. The second method offers an integrated approach to analyzing spatial and temporal (spatiotemporal) patterns of traffic accidents and organizes them according to their level of significance. The spatiotemporal seasonal patterns of traffic accidents were analyzed using the kernel-density estimation; it was then applied as the attribute for a significance test using the local Moran’s I index value. The results of the first method demonstrated that over 90% of hotspot locations in Sherbrooke were located at intersections and in a downtown area with significant conflicts between road users. It also showed that signalized intersections were more dangerous than unsignalized ones; over half (58%) of the hotspot locations were located at four-leg signalized intersections. The results of the second method show that crash patterns varied according to season and during certain time periods. Total seasonal patterns revealed denser trends and patterns during the summer, fall, and winter, then a steady trend and pattern during the spring. Our findings also illustrated that crash patterns that applied accident severity were denser than the results that only involved the observed crash counts. The results clearly show that the proposed methods could assist transport authorities in quickly identifying the most hazardous sites in a road network, prioritizing hotspot locations in a decreasing order more efficiently, and assessing the relationship between traffic accidents and seasons. / Les accidents de la route sont responsables de plus de 1500 décès par année au Canada et ont des effets néfastes sur la société. Aux yeux des autorités en transport, il devient impératif d’en réduire les impacts. Il s’agit d’une préoccupation majeure au Québec depuis que les risques d’accidents augmentent chaque année au rythme de la population. En réalité, les accidents routiers se produisent rarement de façon aléatoire dans l’espace-temps. Ils surviennent généralement à des endroits spécifiques notamment aux intersections, dans les bretelles d’accès, sur les chantiers routiers, etc. De plus, les conditions climatiques associées aux saisons constituent l’un des facteurs environnementaux à risque affectant les taux d’accidents. Par conséquent, il devient impératif pour les ingénieurs en sécurité routière de localiser ces accidents de façon plus précise dans le temps (moment) et dans l’espace (endroit). Cependant, les accidents routiers sont influencés par d’importants facteurs comme le volume de circulation, les conditions climatiques, la géométrie de la route, etc. Le but de cette étude consiste donc à identifier les points chauds au moyen d’un historique des données d’accidents et de leurs répartitions spatiotemporelles en vue d’améliorer la sécurité routière. Cette thèse propose deux nouvelles méthodes permettant d’identifier les points chauds à l’intérieur d’un réseau routier. La première méthode peut être utilisée afin d’identifier et de prioriser les points chauds dans les cas où les données sur le volume de circulation sont disponibles alors que la deuxième méthode est utile dans les cas où ces informations sont absentes. Ces méthodes ont été conçues en utilisant des données d’accidents sur trois ans (2011-2013) survenus à Sherbrooke. La première méthode propose une approche intégrée en deux étapes afin d’identifier les points chauds au sein du réseau routier. La première étape s’appuie sur une méthode d’analyse spatiale connue sous le nom d’estimation par noyau. La deuxième étape repose sur une méthode de balayage du réseau routier en utilisant les taux critiques d’accidents, une démarche éprouvée et décrite dans le manuel de sécurité routière. Lorsque la densité des accidents routiers a été calculée au moyen de l’estimation par noyau, les points chauds potentiels sont ensuite testés à l’aide des taux critiques. La seconde méthode propose une approche intégrée destinée à analyser les distributions spatiales et temporelles des accidents et à les classer selon leur niveau de signification. La répartition des accidents selon les saisons a été analysée à l’aide de l’estimation par noyau, puis ces valeurs ont été assignées comme attributs dans le test de signification de Moran. Les résultats de la première méthode démontrent que plus de 90 % des points chauds à Sherbrooke sont concentrés aux intersections et au centre-ville où les conflits entre les usagers de la route sont élevés. Ils révèlent aussi que les intersections contrôlées sont plus à risque par comparaison aux intersections non contrôlées et que plus de la moitié des points chauds (58 %) sont situés aux intersections à quatre branches (en croix). Les résultats de la deuxième méthode montrent que les distributions d’accidents varient selon les saisons et à certains moments de l’année. Les répartitions saisonnières montrent des tendances à la densification durant l’été, l’automne et l’hiver alors que les distributions sont plus dispersées au cours du printemps. Nos observations indiquent aussi que les répartitions ayant considéré la sévérité des accidents sont plus denses que les résultats ayant recours au simple cumul des accidents. Les résultats démontrent clairement que les méthodes proposées peuvent: premièrement, aider les autorités en transport en identifiant rapidement les sites les plus à risque à l’intérieur du réseau routier; deuxièmement, prioriser les points chauds en ordre décroissant plus efficacement et de manière significative; troisièmement, estimer l’interrelation entre les accidents routiers et les saisons.

L’une des questions primordiales dans l’étude de l’Antiquité tardive concerne le passage de l’ancienne religion polythéiste au christianisme. Or, les découvertes archéologiques faites dans la partie orientale du Bassin méditerranéen ont révélé de nombreux pavements chrétiens (ou juifs) tardifs décorés de riches mosaïques polychromes réutilisant des figures issues de la tradition iconographique grecque, parmi lesquelles des personnifications d’éléments cosmologiques. On rencontre ainsi des éléments du temps, comme les quatre Saisons (Tropai) ou les Mois (Ménès), la Terre (Gê) parfois accompagnée de ses Fruits (Karpoi), certains astres comme le Soleil (Hélios), la Lune (Séléné), parfois accompagnés du Zodiaque, l’Élément marin féminin (Thalassa) ou masculin (Okéanos, Abyssos) et les quatre Fleuves du Paradis (Géon, Phison, Tigre et Euphrate). Cette présente thèse se propose d’étudier chacune de ces personnifications, leur iconographie et leur symbolique, en contexte religieux, mais aussi profane, dans une analyse stylistique et comparative. Cette étude a ainsi pour but de mettre en relief la spécificité de cette partie orientale de l’Empire romain, entre le IVe et le VIe siècle, et d’insister sur la pérennité de la culture grecque et de ses traditions iconographiques, malgré un changement de religion officielle. / One of the primordial questions in the study of Late Antiquity concerns the transition from the ancient polytheistic religion to Christianity. The archaeological discoveries that have been made in the Eastern part of the Mediterranean Basin have revealed a number of late Christian (or Jewish) pavements decorated with rich polychrome mosaics that reuse figures stemming from the Greek iconographic tradition, which include personifications of cosmological elements. In this manner elements of time can be encountered, such as the Four Seasons (Tropai) or the Months (Menes), the Earth (Ge) sometimes surrounded by her Fruits (Karpoi), specific celestial bodies such as the Sun (Helios), the Moon (Selene), sometimes accompanied by the Zodiac, the female marine Element (Thalassa) or the male (Okeanos, Abyssos) and the four Rivers of Paradise (Geon, Phison, Tiger and Euphrates). This thesis makes a stylistic and comparative analysis of each of these personifications, their iconography and their symbolism, in a religious context, but also in a secular one. The object of this study is to emphasise the specificity of the Eastern part of the Roman Empire between the Fourth and the Sixth centuries. And also to insist in particular on the longevity of the Greek culture and its iconographic traditions, despite an official change in religion.

This dissertation thesis focuses on several aspects of fish ecology in reservoirs and the methodology of their sampling. It is divided to three parts. The first part focuses on the dynamics of fish distribution throughout the seasons and between day and night. The second part deals with the efficiency and the selectivity of the beach seine net, trawl and purse seine net. The third part describes the long-term development of fish populations in the Římov Reservoir.

This work is engaged in the reflexis of endangerous of behaviour in the season of adolescence. The first chapter offers a complex, compendious acquainting with life crises in the developement of man with the intention on the crise of adolescence. In conection with this season, there are described fundamental changes that can be the source of critical moments. The second chapter is following up with a critical moments that describes concrete forms of social work with young generation and ethics questions and dilemmas. The third chapter enriches the previous two of the theory of social work that facilitates a daily practise of workers and it specifies for anybody what to do. The last chapter of the work is about the reflex of ethics questions in the social work with adolescence people and their crises and finding the question on it or finding the perspective solutions.

MESHWR / Department of Hydrology and Water Resources / This study dealt with the influence of climate variability on flood and drought cycles and implications on rainy season characteristics in Luvuvhu River Catchment (LRC) in Limpopo of South Africa. Extreme weather events resulting in hazards such as floods and droughts are becoming more frequent due to climate change. Extreme events affect rainy season characteristics and hence have an influence on water availability and agricultural production. Annual temperature was obtained from Water Research Commission for stations 0723485W, 0766628W and 0766898W from 1950-2013 were used to show/or confirm if there is climate variability in LRC. Daily rainfall data was obtained from SAWS for stations 0766596 9, 0766563 1, 0723485 6 and 0766715 5 were used to detect climate variability and determine the onset, duration and cessation of the rainy season. Streamflow data obtained from the Department of Water and Sanitation for stations A9H004, A9H012, and A9H001 for at least a period of 30 years for each station were used for climate variability detection and determination of flood and drought cycles. Influence of climate variability on floods and droughts and rainy season characteristic were determined in the area of study. Trends were evaluated for temperature, rainfall and streamflow data in the area of study using Mann Kendall (MK) and linear regression (LR) methods. MK and LR detected positive trends for temperature (maximum and minimum) and streamflow stations. MK and LR results of rainfall stations showed increasing trends for stations 0766596 9, and 0766563 1 whereas stations 0723485 6 and 0766715 5 showed decreasing trends. Standardized precipitation index (SPI) was used to determine floods and droughts cycles. SPI results have been classified either as moderately, severely and extremely dry or, moderately, very and extremely wet. This SPI analysis provides more details of dominance of distinctive dry or wet conditions for a rainy season at a particular station. Mean onset of rainfall varied from day 255 to 297, with 0766715 5 showing the earliest onset compared to the rest of the stations. Cessation of rainfall for most of the hydrological years was higher than the mean days of 88, 83 and 86 days in 0766596 9, 0766563 1 and 0723485 6 stations. Mean duration of rainfall varied from 102 to 128, with station 0766715 5 showing shortest duration of rainfall. The results of the study showed that the mean onset, duration and cessation were comparable for all stations except 0766715 5 which had lower values. The study also found that climate variability greatly affects onset, duration and cessation of rainfall during dry years. This led to late onset, early cessation and relatively short duration of the rainfall season. Communities within the catchment must be educated to practice activities such as conservation of indigenous plants, reduce carbon dioxide emissions.