Le raisonnement de la fertilisation azotée du blé a, depuis 40 ans, été largement orienté par le consensus autour de la méthode du bilan, avec comme principes fondamentaux : une nutrition azotée non limitante tout au long du cycle et l’estimation, de manière indépendante, des différents termes de l’équation du bilan pour caractériser la fourniture du sol et les besoins en azote de la plante. Au regard des enjeux de réduction des pollutions environnementales, de l’évolution des exigences qualitative du marché, ainsi que des difficultés de mise en oeuvre de la méthode, on s’interroge sur l’opportunité de renouveler ce paradigme. Pour proposer une nouvelle méthode qui réponde aux divers enjeux concernant l’azote, qui valorise au mieux les connaissances disponibles et dont la mise en oeuvre est cohérente avec les moyens des acteurs, nous avons mis en oeuvre une démarche de conception innovante, structurée en 3 étapes : un diagnostic des usages des outils actuels, une phase de conception, incluant des ateliers de conception et la mise au point de règle de décision à l’aide d’un modèle, et un test d’usage du prototype conçu.Le diagnostic des usages a mis en évidence plusieurs obstacles à la mise en oeuvre de la méthode du bilan, dont la fixation de l’objectif de rendement, ce qui a orienté la phase de conception vers l’exploration d’un concept de méthode de fertilisation azotée permettant de s’en affranchir. La méthode mise au point est basée sur le suivi régulier de l’état de nutrition azotée de la plante, l’acceptation de carences en azote non préjudiciables et des règles de décision tenant compte des conditions météorologiques au moment de l’apport. Nous montrons que la conception a rendu nécessaire la production de nouvelles connaissances, mais aussi la diversification des ressources et des compétences habituellement mobilisées. Ce travail enrichit les méthodes de conception d’outils d’aide à la décision en montrant comment l’articulation des 3 étapes permet de sortir du paradigme qui domine la fertilisation azotée depuis des décennies et d’élaborer un outil palliant les défauts des outils actuels. / Decisions about nitrogen fertilizer application on wheat have, for the last 40 years, been based on the balance sheet method, with the following underlying principles: non-limiting nitrogen nutrition throughout the crop cycle, and independent estimation of the various terms of the equation, to characterize soil nitrogen supply and plant nitrogen needs. Environmental pollution, changes in the qualitative requirements of the market and difficulties implementing this method have raised questions about whether it might be appropriate to switch to new ways of managing nitrogen fertilizer. We developed a new method meeting the diverse constraints relating to nitrogen use, making the best use of available knowledge and easily applicable by users, through a 3-steps innovative design approach: a diagnosis of the use of current tools, a design phase including design workshops, production of new knowledge, a modelbased prototyping, and the testing of a prototype method.The diagnosis of uses identified several barriers to the implementation of the balance sheet method, including the need to set a target yield. This directed the design phase towards the exploration of new ways of managing nitrogen fertilizer that did not require the fixing of a target yield. The method developed is based on the regular monitoring of plant nitrogen nutrition, the toleration of periods of nitrogen deficiency that are not prejudicial and the use of decision rules taking weather conditions at the time of nitrogen application into account.This design required the generation of new knowledge and a diversification of the resources and skills usually mobilized. This work enriches the methods for designing decision support tools and shows how a combination of 3 steps can be used to develop a tool for managing nitrogen fertilizer applications completely different from the dominant paradigm of the last 40 years, and compensating the defects of current methods.

Assim como Sócrates representa a filosofia de Platão em seus diálogos e Zaratustra encarna os conceitos da filosofia nietzschiana, também o Meursault de Albert Camus é um avatar para sua filosofia. No eterno presente de Meursault, na terna indiferença de seu amor e abertura ao mundo e ao destino, estão encarnados os principais conceitos da filosofia camusiana. Na obra de Camus, a tragédia do protagonista de O Estrangeiro e sua postura diante do tempo, do mundo e do destino têm sua raiz na tragédia do Mersault de A Morte Feliz e, em última análise, na tragédia do inválido Zagreus: na morte do inválido Zagreus de A Morte Feliz está a tragédia original do Mersault de A Morte Feliz e do Meursault de O Estrangeiro. E Camus não deu o nome de Zagreus a esta personagem por acaso. Na tragédia do inválido Zagreus de A Morte Feliz e na tragédia dos protagonistas de A Morte Feliz e O Estrangeiro, Camus fez referência ao mito de Dioniso Zagreus. Nesta dissertação, mostraremos que a origem da filosofia de Camus em O Estrangeiro e A Morte Feliz está no mito de Dioniso Zagreus e, mais precisamente, no mito de Dioniso Zagreus segundo o interpretou Nietzsche. No conceito de dionisíaco em O Nascimento da Tragédia e nos correlatos conceitos nietzschianos de amor fati e eterno retorno, encontramos o lugar de gênese dos conceitos camusianos de eterno presente, terna indiferença, amor ao destino, amor ao mundo e abertura ao mundo na Tradição Filosófica, encarnados na figura dos protagonistas de O Estrangeiro e A Morte Feliz. Na filosofia de Nietzsche, encontramos a principal influência de Camus para a criação de sua filosofia em O Estrangeiro e A Morte Feliz. / Just as Socrates represents the philosophy of Plato in his dialogues and Zarathustra embodies the concepts of the nietzschian philosophy, the Meursault of Albert Camus is an avatar for his philosophy. In the eternal present of Meursault, in the tendre indifférence of his love and opening towards the world and towards his destiny, the main concepts of the camusian philosophy are depicted. In the works of Camus, the tragedy of Meursault in LÉtranger is originally in the tragedy of the Mersault in La Mort Heureuse, and moreover, in the tragedy of the crippled Zagreus: in the death of the crippled Zagreus in La Mort Heureuse and in the final tragedies of La Mort Heureuse and LÉtranger, Camus referred to the myth of Dionysos Zagreus. In this dissertation, we shall indicate the origin of the philosophy of Camus in LÉtranger and La Mort Heureuse; we shall indicate its origin in the myth of Dionysos Zagreus and, more precisely, in Nietzsches interpretation of that myth. In the nietzschian concept of dionysian and in the related nietzschian concepts of amor fati and eternal recurrence, we have found the main influence in the genesis of the camusian concepts of eternal present, tendre indifférence, love of destiny, love of the world and opening towards the world, all embodied in the Meursault of LÉtranger and in the Mersault of La Mort Heureuse. In the philosophy of Nietzsche, we have found Camus main influence for the creation of his philosophy in LÉtranger and La Mort Heureuse.

Assim como Sócrates representa a filosofia de Platão em seus diálogos e Zaratustra encarna os conceitos da filosofia nietzschiana, também o Meursault de Albert Camus é um avatar para sua filosofia. No eterno presente de Meursault, na terna indiferença de seu amor e abertura ao mundo e ao destino, estão encarnados os principais conceitos da filosofia camusiana. Na obra de Camus, a tragédia do protagonista de O Estrangeiro e sua postura diante do tempo, do mundo e do destino têm sua raiz na tragédia do Mersault de A Morte Feliz e, em última análise, na tragédia do inválido Zagreus: na morte do inválido Zagreus de A Morte Feliz está a tragédia original do Mersault de A Morte Feliz e do Meursault de O Estrangeiro. E Camus não deu o nome de Zagreus a esta personagem por acaso. Na tragédia do inválido Zagreus de A Morte Feliz e na tragédia dos protagonistas de A Morte Feliz e O Estrangeiro, Camus fez referência ao mito de Dioniso Zagreus. Nesta dissertação, mostraremos que a origem da filosofia de Camus em O Estrangeiro e A Morte Feliz está no mito de Dioniso Zagreus e, mais precisamente, no mito de Dioniso Zagreus segundo o interpretou Nietzsche. No conceito de dionisíaco em O Nascimento da Tragédia e nos correlatos conceitos nietzschianos de amor fati e eterno retorno, encontramos o lugar de gênese dos conceitos camusianos de eterno presente, terna indiferença, amor ao destino, amor ao mundo e abertura ao mundo na Tradição Filosófica, encarnados na figura dos protagonistas de O Estrangeiro e A Morte Feliz. Na filosofia de Nietzsche, encontramos a principal influência de Camus para a criação de sua filosofia em O Estrangeiro e A Morte Feliz. / Just as Socrates represents the philosophy of Plato in his dialogues and Zarathustra embodies the concepts of the nietzschian philosophy, the Meursault of Albert Camus is an avatar for his philosophy. In the eternal present of Meursault, in the tendre indifférence of his love and opening towards the world and towards his destiny, the main concepts of the camusian philosophy are depicted. In the works of Camus, the tragedy of Meursault in LÉtranger is originally in the tragedy of the Mersault in La Mort Heureuse, and moreover, in the tragedy of the crippled Zagreus: in the death of the crippled Zagreus in La Mort Heureuse and in the final tragedies of La Mort Heureuse and LÉtranger, Camus referred to the myth of Dionysos Zagreus. In this dissertation, we shall indicate the origin of the philosophy of Camus in LÉtranger and La Mort Heureuse; we shall indicate its origin in the myth of Dionysos Zagreus and, more precisely, in Nietzsches interpretation of that myth. In the nietzschian concept of dionysian and in the related nietzschian concepts of amor fati and eternal recurrence, we have found the main influence in the genesis of the camusian concepts of eternal present, tendre indifférence, love of destiny, love of the world and opening towards the world, all embodied in the Meursault of LÉtranger and in the Mersault of La Mort Heureuse. In the philosophy of Nietzsche, we have found Camus main influence for the creation of his philosophy in LÉtranger and La Mort Heureuse.