The aim of the work is to analyse the production efficiency of conventional and organic farms in the Western Bohemia. Based on the data of questionnaire investigation in 2009 I selected four farms from the Pilsen Region. Evaluative criteria were as follows: the total area under cultivation, farming system (conventional or organic), type of arable crops (especially wheat, oat, potatoes). The data were extracted from terrain investigation, telephone conversations, interview with farmers, yearbook of organic farming, situational review and forecast balance of Czech Statistical Office and Ministry of Agriculture. Supporting data were extracted from ÚZEI database. Crop yields, the costs of crops and selling price in recent 10 years were investigated. From the results it can be concluded, that crop yields in organic farming are lower than crop yields in conventional farming. The yields of wheat growing in organic farming are 40 % lower than in conventional farming. The yields of potatoes growing in organic farming are 40 % lower than in conventional farming and the yields of oat growing in organic farming are 30 % lower than in conventional farming. Production efficiency of chosen crops in organic farming is comparable to conventional farming due to higher redemption price and lower costs. In some organic farms the growing of chosen crops is even more profitable than in conventional farms. Structure of costs in organic farming is the most differential component comparable to conventional farming. It is because of different spending of fertilization and crop management practice.

Après la Révolution Verte, qui débuta dans les années 1960, l’agriculture a pris de nouvelles directions grâce à l’introduction de technologies et de pratiques agricoles modernes (modification génétique de semences, usage intensif d’engrais agricoles, mécanisation des coûts d’exploitation) qui ont permis d’intensifier la production et la productivité agricoles. Ce modèle de production s’est formé au sein de l’agriculture conventionnelle. Cependant, après moins d’un siècle de développement, ce modèle d’agriculture a généré un certain nombre de préoccupations quant à son impact sur l’environnement et la santé de la population. En tant qu’alternative à l’agriculture conventionnelle, l’agriculture écologique - qui se présente sous diverses dénominations (organique, agro-écologique, biologique, entre autres) - se distingue en termes de production et de commercialisation dans des systèmes agroalimentaires locaux et globaux. Son développement a été rendu possible grâce à des investissements économiques du fait aussi bien de grandes entreprises agroalimentaires que de petits agriculteurs qui ont converti leurs exploitations à un mode écologique de production. C’est dans ce contexte que l’on observe les motifs d’adhésion des petits agriculteurs à ce type d’agriculture. Nous privilégions dans cette analyse la place que représente la Qualité de Vie (QV) dans le choix de l’agriculteur familial brésilien et du paysan français, en l’occurrence des horticulteurs maraîchers dans deux régions métropolitaines, la Région Métropolitaine de Belo Horizonte (Brésil) et la Région Métropolitaine de l’Île-de-France (France). Ce questionnement recoupe l’idée de « durabilité », comprise non seulement comme la préservation de l’environnement et des écosystèmes, mais aussi comme la prise en compte du tissu social et des conditions de vie des individus, dans ce cas des agriculteurs. En d’autres termes, nous considérons que l’auto-estime et la satisfaction professionnelle sont intrinsèquement liées aux relations sociales et à l’organisation de l’espace dans lequel elles s’insèrent. A partir d’un échantillon intégrant des agriculteurs écologiques et conventionnels, on montre qu’au-delà de valeurs communes représentant une aspiration à une bonne qualité de vie (possibilités de développer un travail salubre - sans risque pour la santé -, prospère - avec un retour financier suffisant - et plaisant - en tant que source de satisfaction et de reconnaissance sociale -), certaines spécificités propres à chacun de ces groupes existent, par-delà l’appartenance régionale. Mais, dans le même temps, il apparaît également que le rapport à la QV vient renforcer la durabilité des exploitations lorsqu’il est incorporé ou relayé dans les projets de développement agricole local. Le rapprochement entre deux contextes régionaux métropolitains permet de comprendre en quoi il existe une spécificité brésilienne autour des questions de sécurité alimentaire et à quelles conditions certaines approches de gestion en France pourraient inspirer les politiques publiques de la région métropolitaine de Belo Horizonte. / After the Green revolution, which began in the years 1960, agriculture took new directions thanks to the introduction of technologies and modern practices (genetic modification of seeds, intensive use of manures, and mechanization of the farms) which made it possible to intensify the production and raise the agricultural productivity. This model of production was formed within the conventional agriculture. However, after less than one century of development, this model of agriculture generated a number of concerns as well for its environmental impact and as well on public health. As an alternative to the conventional agriculture, the ecological agriculture - with its various denominations (Organic, Agro-ecological, Biological, inter alia) - has created its own marks in terms of production and marketing in local and global agro- alimentary systems. Its development was maintained thanks to growing demand and investment of large agro- alimentary companies and family farmers who converted their surfaces to an ecological mode of production. In this context, the inclusion and the adhesion of the small farmers to this type of agriculture is the main framework of this research. The thesis proposes therefore to carry out a reflection around the social sustainability of the farmers with this main question: “Is ecological agriculture a sustainable solution for all?” - which emerges within a social perspective through the analysis of quality of life of Brazilian family farmers and the French peasants, actives within market-gardening inside metropolitan regions of Belo Horizonte (Brazil) and the Metropolitan region of the Ile-de-France (France). This questioning cross the idea of “sustainability”, understood not only like safeguarding of the environment and the ecosystems, but also as taking into account the "social factory" and the living conditions of the individuals, in this case, of the farmers. Thus, the question of the quality of life (QOL) of the farmers – where self-esteem and the job satisfaction are intrinsically related to the social relations and the organization of the space of which they form part – is analysed. The results show inter alia, that the permanence of the production units depends on the conditions given to its owner, taking account of possibilities of developing a salubrious work (without health risk), prosper (with a sufficient financial return) and pleasant (as a source of satisfaction and social recognition). Our work reaffirms thus that ecological agriculture is in fact sustainable for all when the variables of the QOL of the farmers are potentiated and incorporated in the local agricultural development. In addition it's observed that the relation between the values of the QOL and the regional contexts reflects as well in the capacities of the farmers to carry their work as in their feelings of pleasure and self-confidence, i.e. of personal and professional wellbeing. The specificities around the questions of food security in the Brazilian context direct the future research towards arrangements of management strategies used in France and liable to be adapted to the reality of the Belo Horizonte metropolitan region. / Após a Revolução Verde, iniciada na década de 1960, a agricultura tomou novos rumos graças à introdução de tecnologias e práticas agrícolas modernas (modificação genética de sementes, uso intensivo de insumos industriais, mecanização e redução de custo de manejo) que permitiram intensificar a produção e a produtividade agrícola. Esse modelo de produção conformou-se na agricultura convencional. No entanto, a menos de meio século de seu desenvolvimento, este tipo de agricultura tem causado preocupações sobre o seu impacto no meio ambiente e na saúde da população. Como uma proposta alternativa à agricultura convencional, a agricultura ecológica, sob diversos nomes (Orgânica, Agroecológica, Biologique, dentre outras) tem-se destacado no âmbito dos sistemas agroalimentares locais e globais, tanto em termos de produção quanto de área e comercialização. Seu desenvolvimento tem se sustentado por um mercado de investimentos econômicos, representado por grandes empresas agroalimentares e por pequenos agricultores, que converteram suas áreas para uma maneira ecológica de produção. Diante desse contexto, a inclusão ou adesão dos pequenos agricultores a esse tipo de agricultura motiva uma investigação na esfera social. Assim, a proposta dessa tese é trazer uma reflexão acerca da sustentabilidade social dos agricultores, cuja questão: “A agricultura ecológica é uma solução sustentável para todos?” surge com uma perspectiva social sobre as condições de vida e de trabalho do agricultor familiar brasileiro, e do paysan francês, investidos na prática da horticultura ecológica. Este questionamento recai sobre a ideia de “sustentabilidade”, compreendida não somente no aspecto da preservação do meio ambiente e dos ecossistemas, mas também quanto ao tecido social e à qualidade de vida (QV) dos indivíduos, nesse caso, os agricultores. Desta forma, discute-se a QV dos agricultores, cujas autoestima e satisfação profissional encontram-se intrínsecas às relações sociais e às organizações do espaço ao qual eles se inserem. Os limites espaciais da pesquisa englobam duas regiões metropolitanas, a saber: 1) Região Metropolitana de Belo Horizonte – Brasil e; 2) Região Metropolitana de Île-de-France – França.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The nest refuse of leaf-cutting ants is the depleted material resulted from the degradation of vegetation harvested, after being partially consumed by workers, along with dead ants and remnants of own symbiotic fungus. It is an extremely rich material in many nutrients (N, P, K, Ca, Mg, S) and may act as an important component of the organic matter in tropical soils, influencing the development and diversity of plant species. In addition, as a renewable material, of relatively easy availability and sampling, it may be a compound with a high potential for organic farming. In this study, we evaluated the influence of nest refuse in two distinct situations: i) as a substrate for the production of vegetables and ii) the plant regeneration of newly deforested plots. To this purpose, the experiments were divided into two stages: first, the nest refuse was evaluated as a component in a substrate for production of lettuce seedlings (Lactuca sativa) and arugula (Eruca sativa) at different concentrations. The experimental design was completely randomized, consisting of six treatments and four replications. The treatments were the following mixtures: Control (Cont) considered the basic substrate containing bark of Pinus sp. + sand + vermiculite (3:3:1 v/v); commercial substrate (Tropstrato®- Trop); nest refuse of two species (Atta opaciceps and Acromyrmex balzani) + basic substrate, in two concentrations: 15% and 25% for each of the species tested (AT15, AT25, AC15 and AC25), respectively. All substrates were subjected to chemical analysis for determination of macro- and micronutrients. The influence of the substrate in the development of seedlings was evaluated by height, root length, stem diameter, dry weight and number of leaves at four periods: 15, 20, 25 and 30 days after sowing. For the second stage of the experiment, a portion of 10 m x 5 m was installed in a regeneration area. The plot was divided into 50 sub-plots of 1 m2, of these, 30 subplots were randomly selected for cataloguing herbaceous species present. After that, the original vegetation was completely removed in the whole plot area. Thereafter, it was installed at the center of each subplot a quadrant of 30 cm x 30 cm, 15 of them containing a mixture of a liter of sieved soil with 250 mL of nest refuse of Atta opaciceps (25% of nest refuse) and the remaining quadrants with 1 liter of bare soil (control). The quadrants remained in the field for 150 days to be reforested. Afterwards, richness, abundance, composition and dry biomass of the herbaceous species that colonized the plots were evaluated. Our results showed that the seedlings of vegetables in treatments containing nest refuse of leaf-cutting ants developed as well as those grown in the commercial product taking into account the evaluated attributes. Possibly, the highest average growth rates of seedlings from the AT25 and AC25 treatments are due to higher nutrient concentrations present in the material. The nest refuse also influenced the development of herbaceous species, since plots receiving nest refuse had higher biomass (vigor) in comparison with the control group. However, there was no influence of nest refuse in species diversity between treatments. Our results suggest that nest refuse produced by leaf-cutting ants may have applicability to either production of vegetables or to be disposed in areas that suffered some disturbance, pointing out another ecological service provided by ants. / O lixo de formigas cortadeiras é o material gerado da degradação do material vegetal após ser parcialmente consumido pelas operárias, juntamente com formigas mortas e resquícios do próprio fungo simbionte. É um material extremamente rico em diversos nutrientes e pode atuar como um importante insumo em solos tropicais, influenciando na diversidade e desenvolvimento de espécies vegetais. Além disso, por ser um material renovável, relativamente de fácil disponibilidade e coleta, pode ser um composto com alto potencial em cultivos orgânicos. Nesse estudo avaliamos a influência do lixo em duas situações distintas: i) como substrato para a produção de hortaliças e ii) na regeneração vegetal de parcelas recém desmatadas. Para alcance dos nossos objetivos, os experimentos foram divididos em duas etapas: na primeira, o lixo foi avaliado como componente na formulação de substratos para produção de mudas de alface (Lactuca sativa) e rúcula (Eruca sativa) em diferentes concentrações. O delineamento experimental utilizado foi inteiramente casualizado, formado por seis tratamentos e quatro repetições. Os tratamentos consistiram em: Cont (Pinus sp. + fibra de coco + vermiculita (3:3:1 v/v)); substrato comercial - (Trop); lixo de formigueiros + substrato Cont, oriundo de duas espécies (Atta opaciceps e Acromyrmex balzani) em duas concentrações de 15% e 25% para cada uma das espécies testadas (AT15, AT25, AC15 e AC25), respectivamente. Todos os substratos foram submetidos às análises químicas para determinação de macro e micronutrientes. A influência do substrato no desenvolvimento das mudas foi avaliada pela altura, comprimento da raiz, diâmetro do caule, massa seca e número de folhas, em quatro períodos: aos 15, 20, 25 e 30 dias após a semeadura. Para segunda etapa do experimento, uma parcela de 10 m x 5 m foi instalada em uma área em regeneração. A parcela foi subdividida em 50 subparcelas de 1 m2 destas, 30 subparcelas foram selecionadas aleatoriamente para levantamento das espécies herbáceas presentes. Após isso, a vegetação original foi totalmente removida em toda a área da parcela. Posteriormente, no centro de cada uma das 30 subparcelas foi demarcado um quadrante de 30 cm x 30 cm, sendo 15 contendo uma mistura de solo com Atta opaciceps (25% de lixo), totalizando um litro; e 15 com 1 litro de solo (controle). Os quadrantes permaneceram no local por 150 dias, para serem recolonizados pela vegetação. Após esse período avaliou-se a riqueza, abundância, composição e biomassa seca das espécies herbáceas que colonizaram as parcelas. Os nossos resultados mostraram que as mudas de hortaliças nos tratamentos contendo lixo de formigas cortadeiras se desenvolveram tão bem quanto as do tratamento comercial nos atributos avaliados. Possivelmente, as maiores médias de crescimento das mudas no tratamento AT25 e AC25 devem-se às maiores concentrações de nutrientes presentes no material. O lixo também influenciou o desenvolvimento das espécies herbáceas, as parcelas que receberam lixo apresentaram maior biomassa (vigor) em relação ao grupo controle. Porém, não foi observada influência do lixo na diversidade das espécies entre os tratamentos. Nossos resultados sugerem que o lixo produzido por formigas cortadeiras pode ter aplicabilidades tanto para a produção de hortaliças, quanto para ser inserido em áreas que sofreram alguma perturbação, ressalvando mais um serviço ecológico fornecido pelas saúvas.

食安問題引爆，人們關注入口的食物。人類社會發展歷史中，人類與大自然最貼近的是農業，人類生存動機帶動食農產業創新，追求富足牽動社會演進的動能。社會型態的改變就是社會創新的歷程與成果，食、農與人類的歷史進程、社會的結構、生活習慣、文化的演進、經濟、政治力環環相扣。本研究以臨海農場為例，探討個案廚餘堆肥的創新研發成果，在現有的法規規範下無法進入有機農業市場及肥料市場。研究發現以農業為核心，廚餘堆肥的創新研發，生物的智慧有機農法（Smart Organic Farming Model）對生態農業、傳統有機農業對食農產業是一項翻轉性的變革，也是社會創新。社會創新的成果進入市場機制推廣與銷售將衝擊現有利害關係人與法規政策，建議政府在社會創新的變革，政策政治力及時予以反饋，政策創新，向生態農業永續發展方向調整。 / As the food safety issues attracted prevailing attention in recent years, organic farming is widely considered an important solution of the daunting problem. Advocating eco-friendly farming in Taiwan has encountered two major challenges, however. First, most of the organic farming methods are labor intensive which would be hard to be promoted in rural places where the population are aging rapidly. Second, without the aid of chemicals, the produce production tends to be low, and incomes, therefore, tend to be insufficient for sustaining the family. The social innovation conducted by a French Canadian, Pierre, found a perfect solution for both problems. His smart organic farming, basing on turning kitchen waste to compost, shed a light on the future of organic farming in Taiwan. By experiment and intensive interview, this research shows the potential of this innovative farming method.

Effective microorganisms (EM), a commercial concoction of microbes that includes yeasts, fungi, bacteria and actinomycetes, have been found to be effective in enhancing crop growth by a number of scholars. It is registered in South Africa, but it had not been thoroughly investigated. The present study investigated the effects of EM on growth, yield and quality of tomato (Lycopersicon esculentum Mill), butternut (Curcurbita moschata) and Swiss chard (Beta vulgaris), along with selected soil properties. In field-grown tomato it was observed that the application of EM caused a significant increase in the number of fruits at seven weeks after transplanting. However, plants treated with EM alone, or EM in combination with other amendments, subsequently produced lower yields owing to an outbreak of early and late blights which affected them the most severely. Combined applications of EM with organic amendments improved plant N content and increased soil N content above initial levels. The application of compost resulted in soil N and P concentrations higher than those of the control presumably due to nutrients being slowly released from the compost material. In a follow up greenhouse trial EM application had a negative effect on tomato leaf dry matter yield, number of leaves, number of trusses, fruit yield and number of fruits. The negative effects of EM were ascribed to N immobilization by the EM that could have resulted in reduced N availability to plants. The lower number of fruits associated with EM application resulted in improved average fruit weight of tomatoes grown in the greenhouse, possibly as a result of more assimilates being partitioned to the few fruits EM application also had a negative effect on field grown butternut as reflected by lower total yield, lower marketable yield and lower first grade yield. The results were attributed to immobilization of N induced by application of EM, and to the inability of EM to control pumpkin fly that attacked very young fruit, resulting in their failure to develop or resulting in the down grading of mature fruits. The application of EM alone had a positive but non significant effect on the yields of both the first and second harvests of Swiss chard. However, when applied with compost or goat manure, a non significant negative effect on yield was observed. When applied with inorganic fertilizer, EM had no effect on yield but tended to increase the uptake of nitrogen by Swiss chard. Though goat manure had a narrower C: N ratio than compost, it did not result in greater EM effectiveness as had been hoped. However, goat manure had a more positive effect on soil properties than compost. It increased the N, P, and K contents of the soil and resulted in a narrower C: N ratio of the soil compared to compost. Generally, the results of the four trials conducted with three different crops indicated that EM had inconsistent effects on crop performance.

Im ersten Teil des Heftes wird der Einfluss von Stroh- und Gründüngung auf den Ertrag und die Qualität von Öko-Hafer untersucht. 3-jährige Feldversuche zeigen, dass Strohdüngung einen leichten, nicht signifikanten Ertragsrückgang bei Hafer zur Folge hat. Gründüngung dagegen führt sowohl mit Leguminosen als auch mit Gras zu deutlichen Mehrerträgen. In einem weiteren Beitrag werden 10 Jahre Ökolandbau im Lehr- und Versuchsgut Köllitsch ausgewertet. Dabei zeigt sich, dass trotz negativer Nährstoffbilanzen für N, P, K und Mg lediglich bei K eine Unterversorgung messbar wird. Die Erträge der angebauten Kulturen spiegeln bislang noch keinen K-Mangel wider. Die Humusbilanz der Fruchtfolge ist trotz unterbliebener organischer Düngung positiv. Die Veröffentlichung bietet Informationen für Öko-Landwirte und Umstellungsinteressierte.

The first topic presented in the dissertation thesis is determination of isoprostanes as markers of oxidative stress and other compounds affected by presence of oxidative stress. Isoprostanes iPF2-III, iPF2-VI, iPF2-VI, astaxanthin and polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) were monitored in Atlantic salmon eggs (Salmo salar). Methods for the determination of these compounds have been developed and optimized using chromatographic separation coupled to conventional or mass spectrometric detection. Freshly laid eggs, eyed embryos and non-viable eggs were used to test a general hypothesis that egg viability can be affected by susceptibility to oxidative stress, either through the specific fatty acid concentration and/or the antioxidant capacity of the eggs. Levels of isoprostanes and arachidonic acid (AA) were significantly higher in non-viable eggs than in control (eyed embryos) as well as relative abundance of PUFA. While no difference of isoprostanes was found between freshly laid and control those from the Atlantic stock except iPF2-VI which was observed under the LOQ in the control. Higher levels of PUFA and AA in comparison with the control were observed in the freshly laid eggs. However, the only statistically significant difference was observed in the amount of astaxanthin. Different levels of PUFA and astaxanthin may be related to their biochemical consumption during the development of eggs. This work evaluated potential effect on the viability of eggs Salmo salar due to the presence of oxidative stress. The monitoring of mycotoxins in food and feed was the subject of the second topic. Mycotoxins are secondary metabolites produced by fungi. They are ubiquitous undesirable natural contaminants that are toxic for humans and animals. Today are known more than 500 mycotoxins. However, only few of them are regulated by the European Union. The European Food Safety Authority (EFSA) was asked by the European Commission to provide a scientific opinion on other mycotoxins for which statutory limits could be developed. In this study is proposed simultaneous screening allowing fast, reliable and sensitive approach, identification and quantification of 17 mycotoxins in food and feed sample. The method includes both mycotoxins regulated by the EU and selected mycotoxins required by the EFSA (aflatoxins, deoxynivalenol, nivalenol, zearalenone, fumonisin, ochratoxin A, T-2 toxin, HT-2 toxin, enniatins and beauvericin). Analytes are isolated by the modified QuEChERS method. For separation and target mycotoxins detection, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC –MS/MS) was employed. The method also allows determination of ergot alkaloids (ergocornine, ergosine, ergocryptine, ergocristine and their respective epimers). The developed method was used either for monitoring mycotoxins and ergot alkaloids in feed and raw materials and barley and malt prepared from it.

This project is a Bachelor’s thesis conducted by two students at KTH Royal Institute of Technology. The report aims to assess the implementation of sustainable agriculture at the farm Rosenhill, in the Stockholm region in Sweden, and provide potential agroecological solutions. The assessment of the farm functioned as a case study to explore possible ways to improve sustainable practices in agriculture. The method used for assessing agricultural practices in this thesis was drawn from the existing methods IDEA and complemented with the intent to find agroecological approaches. The data gathering was conducted through interviews and observations at the farm, as well as receiving complementing documents from the farm. The data from the interviews and observation was then compiled into a document and divided up into categories, corresponding to the indicators chosen for the analysis. Each individual indicator was first examined individually and, on this ground, concluding comments on the overall implementation of sustainable agriculture were drawn. Results show that the farm is implementing sustainable agriculture the ectively, however, areas of improvement were also identied. The following agroecological practices were further discussed as potential solutions to problems identied at the farm: Intercropping and/or Companion Planting, Cover-cropping and Reduced Tillage, and Agroforestry. / De a projekt är en kandidatexamensarbete skriven av två studenter på Kungliga Tekniska Högskolan (KTH). Rapporten har som syfte att bedöma implementeringen av hållbart jorbruk på odlingen Rosenhill, i Stockholmsregionen, och ge potentiella agroekologiska lösningar. Bedömningen av odlingen fungerade som en fallstudie för att utforska möjliga sätt att förbättra hållbara tillämpningar inom jordbruk. Metoden som användes i detta arbete för att bedöma tillämpningen av jordbruk hämtades från de existerande metoderna IDEA och RISE och komplementerad med avsikten a hitta agroekologiska angreppssätt. Insamlingen av data gjordes genom intervjuer och observationer, samt dokument från odlingen. Data från intervjuer och observationer sattes samman i ett dokument och delades in i kategorier, motsvarande indikatorer valda för analys. Varje individuell indikator analyserades enskilt först och baserat på detta drogs det avslutande kommentarer på den övergripande implementeringen av hållbart jordbruk. Resultaten visar att odlingen implementerar hållbart jordbruk väl, dock kunde förbättringsområden identifieras. Följande tillämpningar av agroekologi diskuterades som potentiella lösningar till problem som identifierades på odlingen: Samodling av lämpliga grödor, Täckningsgrödor och reducerad jordbearbetning och Skogsjordbruk.

Landscape heterogeneity is thought to differ among farm management types (i.e. organic and conventional), and this difference is hypothesized to result in variations in pest control by natural enemies. However, it is unclear if these variations in pest control are driven by landscape structure or by farm management practices themselves. Remotely sensed datasets were used to describe the landscape structure surrounding a group of organic and conventional caneberry farms in Oregon and Washington that have different leafroller parasitism rates attributed to farm management type. A finer scale survey was done at one of the farms using the remotely sensed data as well as field surveys. Landscape metrics of diversity, richness and percent non-crop were used to describe the landscapes surrounding the farm fields at scales ranging from 0.05 km to 5.00 km for the large scale study, and 0.05 km to 0.20 km for the fine scale study. In the fine scale study, data on parasitoid species assemblages, diversity, and parasitism rate were collected and analyzed against the calculated landscape metrics spatially and seasonally. The purpose of this study was to quantify effects of farm management type on habitat structure, effect of habitat structure on leafroller parasitism rate, and to access correlations between landscape metrics calculated at the landscape and field scale. Overall, the farms were embedded in a landscape that was broadly similar, with very few differences in landscape structure occurring between organic and conventional farms. Organic farms had higher vegetation height class diversity at the largest scale compared to conventional farms, while conventional farms had significantly higher percent non-crop area compared to organic farms. There was no significant effect of any of the calculated landscape metrics on parasitism rates. In the field scale study, no correlations were found between habitat metrics and parasitism rates, or between field based metrics and those calculated at the landscape scale. The results of this study suggest that conventional and organic caneberry farms in the Willamette Valley are broadly similar in the habitat conditions they provide parasitoids. This suggests that management changes to pesticide use alone could increase levels of leafroller biological control on conventional farms to levels that are comparable to those seen on organic farms. Our comparisons of the landscape scale and field scale landscape metrics showed no connection, this suggests that direct comparisons cannot be made with these particular metrics at these very different scales. Rather than comparing these types of data, it may be more useful to combine them in order to increase the resolution and predictive power of remotely sensed data for describing landscapes at broad scales. / Graduation date: 2013

L'un des moyens pour faire face à la réduction de l'utilisation d'intrants de synthèse est de favoriser durablement les services agro-écologiques de la diversité végétale. Pour cela, l'agriculteur devra adapter ses modes de gestion. Ma thèse s'inscrit dans l'objectif finalisé d'apporter à l'agriculteur, de l'aide à la gestion de cette diversité végétale sur le territoire de son exploitation. Je me suis fixé 2 objectifs de recherche : i) vérifier si les interchamps et le stock semencier constituent des sources d'espèces pour le centre des parcelles agricoles et ii) quantifier l'influence de la dynamique de deux grands groupes de facteurs, représentée sous la forme de trajectoires de parcelles, sur la diversité végétale : les pratiques agricoles et les caractéristiques de la mosaïque paysagère.J'ai mené ce travail sur l'ensemble du parcellaire de l'Installation Expérimentale de l'Inra ASTER Mirecourt, dont les systèmes de production (polyculture-élevage bovin laitier) sont convertis à l'agriculture biologique depuis 2004. J'ai caractérisé la végétation - en place dans les interchamps et au centre des parcelles, et dans le stock semencier - des parcelles en prairies permanentes et en champs cultivés selon deux approches complémentaires : taxonomique au rang de l'espèce et fonctionnelle à partir de sept propriétés rendant compte de la dissémination, de l'établissement et de la survie des espèces végétales. J'ai caractérisé les trajectoires des parcelles, sur une durée de neuf ans, soit à partir des pratiques agricoles mises en œuvre chaque année, soit à partir des caractéristiques annuelles de la mosaïque paysagère. Cette mosaïque correspond aux différentes occupations du sol obtenues à partir de relevés de terrain ou d'enquêtes auprès des exploitants.Je montre que le stock semencier et les interchamps ne constituent pas des sources potentielles d'espèces végétales pour le centre des parcelles, champs cultivés ou prairies permanentes. En revanche, ce sont des refuges importants pour une grande partie des espèces prairiales. Au vu de mes résultats, je fais l'hypothèse que les interchamps sont des puits d'espèces adventices en champs cultivés. J'ai également mis en évidence que le gradient fonctionnel de la végétation prairiale entre la bordure et le centre s'étend jusqu'à 2 m seulement.Enfin, la diversité végétale des parcelles étudiées est principalement influencée par la trajectoire des parcelles selon les caractéristiques de la mosaïque paysagère et par les pratiques agricoles mises en œuvre durant l'année en cours. Les caractéristiques du sol ont un rôle très minoritaire. Ces trois groupes de facteurs expliquent à eux seuls plus des trois quarts de la variabilité de la composition fonctionnelle de la végétation.La gestion de la diversité végétale des parcelles agricoles d'une exploitation peut donc être menée en partie par l'agriculteur. Cependant, compte-tenu des effets de la trajectoire des parcelles selon les caractéristiques paysagères, il est nécessaire de mettre aussi en place une gestion collective de la végétation entre les différents acteurs partageant le territoire / One of the means to offset the decrease of pesticide use is to favour agro-ecological services of plant diversity. In this aim, farmer will have to adapt its farming management. My work partly answers to the following applied objective: to bring to the farmer some advices for the management of plant diversity on the farm territory. I have two scientific objectives: i) to verify if field boundaries and soil seed bank are potential sources of plant species for field centres; ii) to quantify the relative influence of dynamics of two factor groups, characterized as field paths, on plant diversity: farming practices and characteristics of landscape mosaïc.I have carried out this study on the experimental farm of INRA ASTER Mirecourt. Its farming systems (mixed crop-dairy systems) have been converted to organic farming since 2004. I have characterized vegetation - established vegetation in field boundaries and in field centres, and vegetation in the soil seed bank - of permanent grasslands and arable fields with complementary approaches: taxonomical approach based on the species, and functional approach based on seven functional properties about dispersal, establishment and persistence of plant species. I have characterized field paths, along nine years, either from farming practices set up on field, either from annual characteristics of landscape mosaïc. I have represented this landscape mosaïc as a mosaïc of distinct land-uses. All of them and their spatialization have been determined from farmer surveys or landscape observations.My results show that soil seed bank and field bboundaries are not potential sources of plant species for field centres, in both permanent grasslands and arable fields. On the other hand, they are efficient refuges for a large part of grassland species. According to my results, I hypothesize that field boudaries are species sinks in arable fields. I also highlight that functional gradient of grassland vegetation in the field edge, between field margins and field centres, is spread until 2 m only.Finally, plant diversity in studied fields is mainly influenced by field path according landscape mosaïc and by farming practices set up the same year of vegetation sampling. Soil characteristics have a minor influence. These three groups of influent factors explain more than 75 % of the functional composition variability of the vegetation in field centres.The management of plant diversity in agricultural fields of a given farm can be partly reach by the farmer. However, according to the effects of field paths about landscape mosaïc, it is necessary to set up a collective management of plant diversity with all actors sharing the studied territory