La co-digestion anaérobie (CoDA) des substrats agro-industriels s’inscrit pleinement dans les objectifs sociétaux d’une gestion optimisée des agroressources, d’une réduction des impacts anthropogéniques, ainsi que d’un développement des énergies renouvelables. Toutefois, en considérant les verrous industriels et scientifiques, il est apparu que la problématique méthodologique, relative à l’étude et à l’optimisation, était primordiale dans l’amélioration des performances méthanogènes en CoDA. En cela, il s’est avéré que le principal actionneur pour l’optimisation de la CoDA soit la formulation du mélange en substrats et co-substrats constituant l’intrant du digesteur. Ainsi, les travaux de thèse étaient inscrits dans un double objectif, industriel et scientifique, dont les résultats ont permis de (i) mettre en œuvre des méthodes simples, peu chronophages et surtout peu coûteuses, pour la caractérisation des intrants et le suivi de la CoDA, (ii) déterminer la relation fondamentale entre la formulation du mélange de substrats et son potentiel biométhanogène, (iii) développer des outils de prédiction du potentiel biométhanogène des mélanges de substrats, ainsi que des biodégradabilités globales et spécifiques de ces derniers, (iv) améliorer la compréhension des interactions entre les substrats codigérés et le consortium microbien de digestion, ainsi que la capacité de ce dernier à s’adapter aux diverses charges organiques qui lui sont appliquées (capacité homéostasique). / The co-digestion of agro-industrial substrates in anaerobic conditions falls within the objectives of an optimized management of agricultural resources along with reduction of anthropogenic impacts and development of renewable energies. Considering scientific and industrial bottlenecks from literature review, it could be identified that a methodological approach was the key to an enhanced understanding of anaerobic co-digestion. Ultimately, formulation of the substrate and co-substrates (digestor’s inputs) appeared to be the main actuator to optimize anaerobic co-digestion. Conciliating both scientific and industrial issues, this thesis led to the following findings : (i) an implementation of simple and cost-saving methods to characterize the inputs of digestor and biogas production, (ii) a determination of fundamental relationship between substrate blend and his biomethane potential, (iii) a development of predictive tools for biomethane potential of substrate blends as well as global and specific biodegradability of substrates, (iv) an enhanced comprehension of first, interactions between codigested substrates and the microbial consortium and second, the adaptation capacity of the microbial consortium to various organic loading (homeostatic capacity).

La valorisation non alimentaire de la biomasse végétale représente un enjeu actuel majeur dans le contexte du développement de la bioraffinerie végétale. En Champagne-Ardenne, la transformation des co-produits d'origine agricole fait l'objet d'études importantes. Le son et la paille, co-produits abondants de la filière blé, sont riches en hémicelluloses, polysaccharides constitués essentiellement de pentoses, majoritairement de D-xylose. La principale voie de valorisation des pentoses tels que le xylose est leur fonctionnalisation par voie chimique, mais l'utilisation d'enzymes telles que des xylanases et des β-xylosidases représente une voie de synthèse plus respectueuse de l'environnement et permettant, en outre, d'accéder à de nouvelles molécules inaccessibles par la voie chimique classique (DP plus importants). L'étude conduite dans le cadre de la thèse a concerné l'évaluation et l'amélioration de la synthèse enzymatique par transglycosylation d'alkyl xylosides et oligoxylosides catalysée par une β-xylosidase et deux xylanases. Une seconde voie de valorisation enzymatique a été étudiée, à savoir la synthèse de xylosides et oligoxylosides présentant des propriétés biologiques pouvant notamment être exploitées pour des applications cosmétiques. A travers la mutagénèse dirigée au niveau du sous-site aglycone d'une β-xylosidase de Bacillus halodurans, nous avons montré l'importance de résidus aromatiques de ce sous-site sur les capacités d'hydrolyse et de transglycosylation de l'enzyme. Les résultats obtenus nous ont permis de dégager quelques pistes d'ingénierie du sous-site aglycone de la xylosidase pour optimiser les rendements de transglycosylation en présence d'alcools à longues chaînes carbonées. L'étude de l'effet des conditions réactionnelles sur la synthèse d'alkyl oligoxylosides catalysée par deux xylanases (l'une de Thermobacillus xylanilyticus, l'autre commerciale) a montré la possibilité de produire les alkyl oligoxylosides par voie enzymatique avec des rendements satisfaisants, notamment en réduisant les problèmes physiques d'accessibilité de l'alcool au site actif de l'enzyme. Nous avons également mis en évidence des profils de synthèse différents d'une enzyme à l'autre mais également en fonction des conditions réactionnelles, notamment en ce qui concerne le DP moyen. Notre étude montre également que la synthèse d'alkyl oligoxylosides est possible directement à partir de son de blé prétraité par voie hydrothermale. En ce qui concerne les propriétés physico-chimiques des produits de transglycosylation, nous avons montré que, tout en étant non purifiés, les pentyl et octyl β-D-oligoxylosides obtenus par synthèse enzymatique présentent des propriétés comparables à celles de produits commerciaux utilisés pour leurs propriétés tensio-actives. L'étude de méthodes de synthèse enzymatiques et chimio-enzymatique de xylosides et d'oligoxylosides ciblés pour certaines propriétés biologiques a montré que les deux xylanases étudiées précédemment pouvaient utiliser en tant qu'accepteur, en plus des alcools linéaires, des alcools aromatiques, des diols ou encore un ester ou un alcyne, ce qui a permis d'accéder à des produits originaux. Des tests biologiques réalisés sur des fibroblastes humains, ont montré que les xylosides et oligoxylosides ainsi produits ne sont pas cytotoxiques. Des tests sur l'initiation de la biosynthèse de glycosaminoglycanes, menés avec certains produits, ont conduit à des résultats positifs pour la biosynthèse d'acide hyaluronique. / Non-food valorization of plant biomass currently represents a major challenge in the context of plant biorefinery. In Champagne-Ardenne, the processing of agricultural by-products is the subject of numerous studies. Wheat bran and straw are abundant agricultural by-products and are rich in hemicelluloses, which are polysaccharides essentially constituted by pentoses, mainly D-xylose. The major route for the valorization of pentoses such as xylose is their functionalization by chemical means. Nevertheless, the use of enzymes, such as xylanases and β-xylosidases, represents a more environmentally friendly way and can also lead to the synthesis of new molecules inaccessible through conventional chemistry. The study conducted during the PhD concerned the evaluation and the improvement of the enzymatic synthesis by transglycosylation of alkyl xylosides and oligoxylosides catalyzed by a β-xylosidase and two xylanases. The second pathway for enzymatic valorization investigated was the synthesis of xylosides and oligoxylosides with biological properties that could be applied for cosmetic use.By site-directed mutagenesis in the aglycone subsite of a β-xylosidase from Bacillus halodurans, we have shown the role of aromatic residues on the hydrolysis and transglycosylation capabilities of the enzyme. The results obtained allowed us to identify some engineering of the aglycone subsite of the β-xylosidase to optimize the transglycosylation yields in the presence of alcohols with long carbon chains.The study of the effect of the reaction conditions on the synthesis of alkyl oligoxylosides catalyzed by two xylanases (one from Thermobacillus xylanilyticus and other is commercially available) has shown the ability to produce alkyl oligoxylosides by enzymatic synthesis with acceptable yields. We also pointed out that, depending on the reaction conditions, the products obtained were different particularly as regards the average DP. Our study has also shown that the synthesis of alkyl oligoxylosides is possible directly from hydrothermally pretreated wheat bran. Concerning the physico-chemical properties of transglycosylation products, we have demonstrated that non purified pentyl and octyl β-D-oligoxylosides obtained by enzymatic transglycosylation exhibit similar properties than commercial products used for their surface-active properties. The study of enzymatic an chemo-enzymatic methods for the synthesis of xylosides and oligoxylosides targeted for their biological properties showed that both xylanases previously studied could use linear alcohols but also aromatic alcohols, diols, ester or alkyne alcohols as acceptors for the preparation of original compounds. Biological tests performed on human fibroblasts pointed out that the xylosides and oligoxylosides produced are not cytotoxic. Initiation of the biosynthesis of glycosaminoglycans tested with some of the products has led to positive results for the synthesis of hyaluronic acid by the fibroblasts.

L'effondrement du FONADER (Fonds national de développement rural) qui avait initié les premiers partenariats entre petits exploitants de palmiers à huile et agro-industries au Cameroun, les programmes d'ajustement structurels, la dévaluation du Franc CFA, les crises économiques, et la baisse du prix du cacao et du café sur le marché international, ont conduit à l'émergence d'une nouvelle catégorie de producteurs d'huile de palme indépendants. Ces planteurs de palmiers à huile se sont retrouvés sans soutien technique et ont confié le traitement de leurs régimes aux moulins artisanaux. Les nombreuses difficultés rencontrées par ces petits exploitants se sont traduites par de très faibles rendements enregistrés dans leurs plantations. À la lumière de l'intérêt récent manifesté par de nouvelles agro-industries à investir dans le secteur du palmier à huile au Cameroun, et la décision des entreprises déjà établies d'étendre leurs superficies, l'étude signale que pour atténuer les crises sociales et environnementales résultant des conflits fonciers et de la dégradation des forêts, l'approche la plus durable pour développer le secteur serait de réorganiser des partenariats gagnant-gagnant et équitables entre les planteurs de palmiers à huile et les agro-industries.Au Cameroun, quatre des sept bassins de production d'huile de palme développés pendant le régime de partenariat FONADER ont été sélectionnés comme sites d'étude. Il s'agit d'Eseka dans la région Centre, Dibombari dans la région du Littoral, Muyuka et Lobe dans la région Sud-Ouest. Les agro-industries respectives sont Socapalm, CDC et Pamol. En Malaisie et en Indonésie, les sites de l'étude comprennent le site FELDA de Besout dans le district de Batang Padang, les modèles PIR et KKPA de PT. SAL dans le district de Bungo, le modèle KKPA de PT. Megasawindo et PT. Musim Mas dans les districts de Bungo et Pelalawan respectivement. La collecte des données a été organisée par l'administration de questionnaires et des interviews répétés avec les différents intervenants dans le secteur, des discussions de groupes, des recherches sur Internet et dans les bibliothèques des instituts de recherche spécialisés, ainsi que par des visites d'observation sur le terrain.L'étude porte sur l'origine et l'évolution des régimes de partenariat entre les petits exploitants d'huile de palme et les agro-industries, les points positifs et négatifs des divers modèles testés, et les raisons à l'origine des succès et des échecs enregistrés. L'étude a examiné plus en profondeur les forces et les faiblesses des petits exploitants indépendants de palmiers à huile d'aujourd'hui et les raisons pour lesquelles ces petits exploitants préfèrent traiter leurs régimes dans les moulins artisanaux malgré la présence de moulins industriels plus performants à proximité de leurs plantations. L'étude a en outre cherché l'inspiration auprès des expériences positives et négatives de grands projets en Malaisie et en Indonésie, les deux géants de la production mondiale d'huile de palme à travers des études de cas. Enfin, une approche participative prospective sur l'avenir du secteur de l'huile de palme organisée dans trois ateliers au Cameroun, a permis de générer des recommandations de politique sur la voie à suivre pour développer des partenariats équitables et durables entre les petits exploitants de palmiers à huile et les agro-industries au Cameroun.Mots-clés: partenariat, FONADER, FELDA, PIR, KKPA, agro-industrie, petits exploitants, agriculture contractuelle. / The collapse of the FONADER sponsored partnership between oil palm smallholders and major agro-industries in Cameroon together with the structural adjustment program, the devaluation of the Franc CFA, the economic crises, as well as the fall in the international market price for cocoa and coffee, led to the emergence of independent oil palm producers in the country. These oil palm planters have been grappling with the management of their plantation and the processing of their FFB with the use of artisanal mills. But the numerous difficulties faced by these smallholders are translated into very low yields registered in their plantations. In the light of the recent interest expressed by new agro-industries to invest in the oil palm sector in Cameroon, and the decision by old companies to expand their surface areas, the study notes that in order to mitigate some of the social and environmental crises that result from land conflicts and forest degradation, the most sustainable approach to develop the sector will be to revamp win-win and equitable partnerships between oil palm planters and agro-industries.In Cameroon, four of the seven palm oil production basins carved out during the FONADER partnership scheme where selected for our study sites. They included Eseka in the Center region, Dibombari in the Littoral region, Muyuka and Lobe in the Southwest region. The respective agro-industries were Socapalm, Cameroon Development Corporation (CDC) and Pamol. In Malaysia and Indonesia, the study sites were the FELDA scheme of Besout in the district of Batang Padang, the PIR and KKPA scheme of PT SAL in the district of Bungo, the KKPA scheme of PT Megasawindo and PT Musim Mas in the district of Bungo and Pelalawan respectively. Data collection was organized through the administration of semi-guided questionnaires, secondary data sourcing, personal communication with different stakeholders in the sector, focus group discussions, internet and library search, as well as field observation visits.The study looked at the origine and evolution of partnership schemes between oil palm smallholders and agro-industries, what was right, what went wrong in the course of time, and why most partnerships collapsed. The study further looked at the strengths and weaknesses of today's independent oil palm smallholders and the reasons why these smallholders prefer to process their FFB in artisanal mills despite the presence of agro-industrial mills at the vicinity of their plantations. The study further drew inspiration on the positive and negative experiences of major schemes in Malaysia and Indonesia which have boosted production in their oil palm sector through case studies as well as through a participatory prospective analysis workshop in Cameroon on the future of the palm oil sector, as a way to generate policy recommendation on the way forward for future partnership schemes between oil palm smallholders and agro-industries in Cameroon.Keywords: Partnership, FONADER, FELDA, PIR, KKPA, agro-industry, smallholder, outgrower schemes.

Dans un contexte où l’utilisation de substance chimique en agriculture est de plus en plus décriée, il est nécessaire de trouver de nouveaux moyens de protections des cultures, tout en maintenant une agriculture économiquement performante. Ainsi, un peptide extrait de graines de pois nommée PA1b (Pea Albumin 1 sous-unité b), présentant une forte activité insecticide a été découvert au laboratoire. PA1b provoque chez l’insecte modèle du laboratoire, le charançon des céréales Sitophilus sp., 100% de mortalité. L’action de PA1b passe par la liaison à un récepteur présent chez les charançons sensibles, et cette liaison est absente chez les charançons résistants ; ce récepteur est une pompe à protons nommée V-ATPase pour Vacuolar ATPase. Elle est composée de 14 sous-unités organisées en deux complexes protéiques nommés V1 (intracellulaire) et V0 (membranaire). PA1b agissant à l’extérieur des cellules seul le complexe V0 composé des sous - unités a, c, d et e pouvait être le récepteur de notre toxine. Mon premier objectif de thèse a été de comprendre le mode d’action de PA1b, en identifiant d’abord la ou les sous-unités réceptrices de PA1b, puis en recherchant par quel mécanisme la liaison de PA1b induit la mort de l’insecte. Nous avons cloné chez le charançon tous les gènes du complexe Vo, puis j’ai complémenté des levures déficientes pour ces gènes. Ce travail, mais également celui réalisé en collaboration avec d’autres équipes, nous a permis de proposer un modèle de perception de PA1b qui implique les sous-unités c et e de la V-ATPase, et permet également de proposer des hypothèses pour les différentes résistances au peptide. Par des méthodes d’immunohistologie et de biochimie, j’ai ensuite montré de manière concordante que la liaison de PA1b à la V-ATPase déclenche un phénomène d’apoptose qui conduit à la mort cellulaire, puis à la mort de l’insecte. Le second objectif de ma thèse était la mise en place d’un système de production hétérologue de PA1b. Grâce à l’expression hétérologue par infiltration de feuille de tabac (Nicotiana benthamiana) nous avons mis en place une technique de production efficace de la protéine PA1b. Après avoir déterminé les parties du gène codant PA1b nécessaires à la production de la protéine fonctionnelle, le système de production a ensuite été simplifié par la construction d’une cassette d’expression. Ainsi six isoformes de PA1b présents chez le pois, dont l’activité individuelle restait inconnue, ont été produits et testés, permettant de montrer que le caractère amphiphile de PA1b était primordial pour son activité. Par cette technique nous avons mis en place un système de production rapide et efficace permettant de tester la toxicité de nombreux isoformes de PA1b. Ce travail sera une aide précieuse pour le projet, dont l’un des objectifs majeurs est l’optimisation de PA1b, c’est-à-dire de déterminer la séquence peptidique la plus toxique. / In a context where chemical pesticides are increasingly criticized, new crops protection strategies that do not affect agriculture efficiency and productivity, must be found. A new peptide extracted from pea (Pisum sativum) seeds, named PA1b (Pea albumin 1 subunit b), and showing an important insecticide activity, was discovered in our laboratory. PA1b induces 100% mortality in our insect model, the cereal weevil, Sitophilus sp. PA1b acts by interacting with a receptor, this interaction is present in sensitive weevil, but not present in resistant weevil. The PA1b receptor is the vacuolar H+ -ATPase (V-ATPase), a multi-subunit proton pump. The V-ATPase is composed of two functional protein complexes named V1 (in the cytoplasm) and V0 (in the membrane). As PA1b is known to act only in the extracellular space, thus only the V0 complex, composed on the subunits a, c, d and e, can be the toxin receptor. The first aim of this thesis is to understand the PA1b mode of action: (i) identifying the subunit(s) acting as the receptor(s), (ii) understanding how the binding mechanism of PA1b on the receptor lead to the insect death. The weevil V0 complex genes were cloned and we used them for a functional complementation tests in yeasts strains deleted for these genes. Our data, together with those obtained through collaboration, lead to the proposal of model for the PA1b perception signaling which would involve subunits c and e of the V-ATPase. The identification of the PA1b receptor allows us to propose a hypothetical model explaining resistance mechanism to the peptide. Using immunohistology and biochemistry methods, we showed that PA1b-receptor interaction induced cells death triggered by apoptosis thus leading to insect death. The second aim of this thesis was the development of a PA1b heterologous production system. Through Agrobacterium tumefaciens mediated transient transformation by infiltration in tobacco leaves (Nicotiana benthamiana) an efficient system for PA1b production was developed. After identification of the essential parts of the complex PA1 gene necessary for efficient PA1b production, we created an expression cassette to simplify our heterologous production system. We used the system to produce six pea PA1b-isoformes with unknown individual toxic activity. The isoforms toxicity was experimentally determined, and our data showed that the amphiphilic properties of PA1b are essential for the maintenance of its toxic activity. For the first time, we implemented a quick and efficient production system, which allows to produce and to test many naturals or synthetics PA1b isoforms. This work will be useful to achieve one of the most important objectives of the research on this molecule, that is the identification.

Eutrophication of seas, particularly near the coasts, is a topic of high current concern. Itleads to increased primary production and a higher frequency of algal blooms. The enhancedprimary production also increases the turbidity of the water, making it harder for ecologicallyimportant benthic macro algae, e.g. seaweed, to colonize bottoms on deeper waters. EU directives, as well as national law, demand decreases in nutrients, e.g. nitrogen, reachingthe sea. Another approach to decreasing the amount of nutrients in the sea could be musselfarming. Mussel farming is an established, albeit small, industry on the Swedish west coast. The useof mussels to remove nitrogen, however, is a more recent application. Lysekil municipalityhas been granted exemption from improving the nitrogen removal in Långevik waste watertreatment plant. Instead, mussel farms are used to remove nitrogen, which was estimated to bea less costly solution. This thesis investigates the advantages in money and energy in using mussel farming. Theuse of a mussel farm to remove nitrogen from sea water is compared with removing nitrogenin a WWTP. In addition, the production of mussel fertilizer, through a composting process, iscompared with producing a corresponding amount of artificial fertilizers. The results show that mussel farms are neither more economic nor energy efficient inremoving nitrogen and producing fertilizer than the conventional alternatives examined Mussel fertilizer, however, is not the most lucrative product that the mussels from the farmcan give. Alternatives, such as fodder or human consumption, are discussed in the report. Furthermore, the mussel fertilizer qualifies as organic fertilizer. A comparison with otherorganic fertilizers could prove mussels more economic or energy efficient, but such acomparison is out of the scope for this thesis. Finally, some data, e.g. the energy demand for nitrogen removal in the WWTP, were roughestimations. More research and investigations are needed in order to achieve more accurateconclusions. / Eutrofiering i haven, speciellt kustnära vatten, är ett högaktuellt problem. Det leder till ökadprimärproduktion och frekvens av algblomningar. Den förhöjda primärproduktionen lederäven till ökad turbiditet, något som försvårar för ekologiskt viktiga bentiska arter, t.ex. sjögräs(ålgräs), att kolonisera bottnar på djupare vatten. Så väl EU-direktiv som nationell lagstiftning kräver en minskning i näringsämnen, bl.a.kväve, som når havet. Ett verktyg för att klara av dessa minskningar kan vara musselodlingar. Musselodling är en etablerad, men liten, industri på den svenska västkusten. Musslor som enkväveavskiljningsmetod är däremot en ny tillämpning. Lysekil kommun har fått undantag frånatt bygga ut kvävereningen i Långevik vattenreningsverk. I stället används musselodlingar föratt ta bort kväve, vilket ansågs vara en billigare metod. Detta examensarbete undersöker fördelarna i pengar och energi i att användamusselodlingar för att få bort kväve från havsvatten, jämfört med att avskilja kväve ivattenreningsverk. Dessutom jämförs produktionen av musselgödning, genom att komposteramusslor från musselodlingen, med att producera motsvarande mängder med konstgödsel. Resultaten visar att musselodlingar vare sig är billigare eller mer energieffektiva än dekonventionella alternativen för att ta bort kväve och producera gödsel. Musselgödning är däremot inte den mest lönsamma produkt som musslorna frånmusselodlingen kan ge. Alternativ som foder och mänsklig konsumption diskuteras i rapporten. Vidare kan musselgödning godkännas som KRAV-gödsel. I en jämförelse mot andraKRAV-gödsel kan musselgödning visa sig mer ekonomisk eller energieffektiv, men en sådan jämförelse ligger utanför detta arbetes tidsram. Slutligen var vissa data grova uppskattningar, t.ex. energiåtgången för kväveavskiljning i vattenreningsverk. Mer forskning och undersökningar behövs för att nå mer tillförlitligaslutsatser. / www.ima.kth.se

South Africa’s sluggish economic growth and limited structural transformation are at the core of the country’s high levels of unemployment and poverty. Why some countries are able to grow and others not has been the subject of much academic debate, with recent literature throwing fresh light on the phenomenon by exploring the relationship between growth and a country’s productive structure. It is argued that countries’ heterogeneous productive structures stem from differences in entrenched capabilities and know-how in producing and marketing a very specific set of products. Investigating and comparing what countries actually produce and how this supports economic development yield valuable insights into why countries differ and what their transformation priorities should be. In this study a new analytical approach is adopted to determine the potential growth paths of South Africa’s broader agricultural sector, the so-called agro-complex. Comprising 1 456 primary and processed products as well as production inputs within the food, feed and fibre segments, this broad sector makes an important contribution to economic development through its direct and indirect linkages with other economic sectors as well as its relatively high labour absorption rate. The wide-ranging economic challenges that South Africa faces have clearly gripped the country’s agro-complex. A growing dependency on imports of higher value, processed food has led to deteriorating terms of trade, while limited innovation and diversification in agricultural exports (coupled with a high proportion of re-exports) is seriously constraining the positive impact that the agro-complex could have on the country’s growth rate. In this study, the productive structure of the agro-complex is analysed through the application of the ‘product space’ framework. This methodology investigates the relatedness between products as reflected in the conditional probability of a product being exported in tandem with another product, considering all global trade flows. The proximity value, the measurement of relatedness, between all 1 456 products is used to arrive at the structure and visible evidence of an agricultural product space network. This structure allows potential diversification pathways to be analysed. Research has shown that a country’s diversification process involves moves along pathways to nearby - and thus related – ‘new’ products, which simplifies the redeployment of existing productive capabilities and knowledge. These pathways are identified according to three strategic values, namely structural transformation, market potential and employment creation. The potential for structural transformation is determined by using a product-level measure of complexity, with higher level complexity (i.e. upgrading) going to the core of structural transformation. The potential market demand is determined by examining the prospects for import substitution; producing re-exported products locally; producing new, high-potential export products; and diversifying into new markets with existing export products (with the latter two categories evident in the results of a Decision Support Model (DSM)). Finally, the potential for employment creation is analysed in the light of labour and human capital intensities at product level. The study found that South Africa’s position in the agricultural product space is relatively dispersed. This position is characterised by a proportionally high level of core competencies within the primary agricultural cluster and a limited amount of vertical linkages. Furthermore the analyses showed that, especially the products for which South Africa has developed a significant high level of specialisation such as plums and wines are located in the sparser, less promising, parts of the agricultural product space. Notwithstanding, a total of 60 realistic diversification opportunities are within “reach” from the countries core competencies in the agro-complex. The analysis on structural transformation established that the level of product complexity within the agro-complex is more important for economic development than product diversity per se. It was revealed that South Africa only ranked 69th globally with regards to the complexity of its agro-complex. It was determined that upgrading within the forestry and agro-processing of food clusters hold the most potential for improving this position. The investigation into the potential for diversification driven by market potential revealed fore mostly that the potential for substituting imports as well as re-exports with local production is limited. The market prospects for exporting “new” products and expanding the export destinations of existing products within the agro-complex is much more favourable. It was estimated that most employment creation could be derived from diversification within the primary agricultural cluster although its number of opportunities are limited. Diversification within both the primary agricultural and agro-processing of food clusters was found the have to most favourable prospects for developing the level of human capital within the agro-complex. Based on all three strategic values, the most promising diversification opportunities are located within the forestry cluster. The range of realistic opportunities within the five clusters of the agro-complex form the core for developing product-level diversification strategies. This will ultimately strengthen the position of the agro-complex and boost South Africa’s growth path for the next decade. Hence, the main contribution of this study includes the determination of the structure of South Africa’s agro-complex from a product perspective and its implications for potential growth and development. / PhD (International Trade), North-West University, Potchefstroom Campus, 2014

South Africa’s sluggish economic growth and limited structural transformation are at the core of the country’s high levels of unemployment and poverty. Why some countries are able to grow and others not has been the subject of much academic debate, with recent literature throwing fresh light on the phenomenon by exploring the relationship between growth and a country’s productive structure. It is argued that countries’ heterogeneous productive structures stem from differences in entrenched capabilities and know-how in producing and marketing a very specific set of products. Investigating and comparing what countries actually produce and how this supports economic development yield valuable insights into why countries differ and what their transformation priorities should be. In this study a new analytical approach is adopted to determine the potential growth paths of South Africa’s broader agricultural sector, the so-called agro-complex. Comprising 1 456 primary and processed products as well as production inputs within the food, feed and fibre segments, this broad sector makes an important contribution to economic development through its direct and indirect linkages with other economic sectors as well as its relatively high labour absorption rate. The wide-ranging economic challenges that South Africa faces have clearly gripped the country’s agro-complex. A growing dependency on imports of higher value, processed food has led to deteriorating terms of trade, while limited innovation and diversification in agricultural exports (coupled with a high proportion of re-exports) is seriously constraining the positive impact that the agro-complex could have on the country’s growth rate. In this study, the productive structure of the agro-complex is analysed through the application of the ‘product space’ framework. This methodology investigates the relatedness between products as reflected in the conditional probability of a product being exported in tandem with another product, considering all global trade flows. The proximity value, the measurement of relatedness, between all 1 456 products is used to arrive at the structure and visible evidence of an agricultural product space network. This structure allows potential diversification pathways to be analysed. Research has shown that a country’s diversification process involves moves along pathways to nearby - and thus related – ‘new’ products, which simplifies the redeployment of existing productive capabilities and knowledge. These pathways are identified according to three strategic values, namely structural transformation, market potential and employment creation. The potential for structural transformation is determined by using a product-level measure of complexity, with higher level complexity (i.e. upgrading) going to the core of structural transformation. The potential market demand is determined by examining the prospects for import substitution; producing re-exported products locally; producing new, high-potential export products; and diversifying into new markets with existing export products (with the latter two categories evident in the results of a Decision Support Model (DSM)). Finally, the potential for employment creation is analysed in the light of labour and human capital intensities at product level. The study found that South Africa’s position in the agricultural product space is relatively dispersed. This position is characterised by a proportionally high level of core competencies within the primary agricultural cluster and a limited amount of vertical linkages. Furthermore the analyses showed that, especially the products for which South Africa has developed a significant high level of specialisation such as plums and wines are located in the sparser, less promising, parts of the agricultural product space. Notwithstanding, a total of 60 realistic diversification opportunities are within “reach” from the countries core competencies in the agro-complex. The analysis on structural transformation established that the level of product complexity within the agro-complex is more important for economic development than product diversity per se. It was revealed that South Africa only ranked 69th globally with regards to the complexity of its agro-complex. It was determined that upgrading within the forestry and agro-processing of food clusters hold the most potential for improving this position. The investigation into the potential for diversification driven by market potential revealed fore mostly that the potential for substituting imports as well as re-exports with local production is limited. The market prospects for exporting “new” products and expanding the export destinations of existing products within the agro-complex is much more favourable. It was estimated that most employment creation could be derived from diversification within the primary agricultural cluster although its number of opportunities are limited. Diversification within both the primary agricultural and agro-processing of food clusters was found the have to most favourable prospects for developing the level of human capital within the agro-complex. Based on all three strategic values, the most promising diversification opportunities are located within the forestry cluster. The range of realistic opportunities within the five clusters of the agro-complex form the core for developing product-level diversification strategies. This will ultimately strengthen the position of the agro-complex and boost South Africa’s growth path for the next decade. Hence, the main contribution of this study includes the determination of the structure of South Africa’s agro-complex from a product perspective and its implications for potential growth and development. / PhD (International Trade), North-West University, Potchefstroom Campus, 2014

Food processing micro- and small-scale enterprises (MSEs) play an important role in the national economic development of Tanzania. Though many of them have great growth potential, they face a number of constraints hindering further development, and large amounts of cooking oil are imported each year. The aim of thesis has therefore been to identify and analyse the different factors affecting these MSEs in order to find out which the major growth challenges are. The case study is mainly based on individual semi-structured interviews with sunflower oil processors and farmers in Babati districts, conducted in February and March 2016, and earlier research and studies on the topic of MSE growth make up the theoretical framework used for analysis of the data. The findings show that there are indeed numerous challenges facing these processors, and the major constraint was found to be lack of capital; an issue causing or worsening a majority of the other challenges at hand. Other problems are related to raw material, equipment & electricity for processing, regulations, market accessibility, and competition. These obstacles need to be overcome in order to enable the industry's expansion within and outside of Tanzania, and further research is recommended.

Les indications géographiques (IG) sont un instrument de plus en plus utilisé dans le monde entier. Sujet fréquent des négociations de commerce international, la régulation des IG est un des thèmes les plus importants dans les discussions concernant l'organisation du système agroalimentaire mondial, dans la mesure où il concerne un ensemble de questions autour des droits de propriété intellectuelle et de l'accès aux marchés. Opposé à un processus de standardisation de la production et de la consommation alimentaire, les IG cherchent à valoriser la diversité et l'originalité de produits ancrés dans des territoires spécifiques, mettant l'accent sur les biens immatériels (savoir-faire, tradition, habitudes, façon de produire etc.). Pourtant, il s'agit d'un concept générique qui peut être utilisé dans différents contextes et par des acteurs sociaux les plus divers, y compris pour ceux qui sont dehors du territoire. Chaque projet d'indication géographique est composé par un réseau sociotechnique hétérogène, au sein duquel sont négociées différentes conceptions de qualité et où des valeurs sont en conflit permanent. L'institutionnalisation des règles et des modes de production qui permettent aux acteurs d'échanger est le résultat de ce processus de négociation où des compromis entre des valeurs différentes sont constitués. Dans le monde des vins, les indications géographiques ont été pendant longtemps un concept qui était presque exclusivement lié à un modèle de production lié à la valorisation de terroirs distincts, à l'institutionnalisation de la rareté et à des méthodes traditionnelles de viticulture et de vinification. Cependant, les changements en cours sur le marché mondial, associés à l'entrée en scène de nouveaux acteurs et de nouvelles conventions qualitatives, ont commencé à transfigurer la vie des terroirs et la notion même d'indication géographique. Son adaptation aux nouveaux enjeux économiques a révélé la façon dont ce mécanisme peut être adapaté à différents objectifs. Dans cette thèse, nous révèlons que le développement récent de cet instrument de qualification dans le secteur vitivinicole exprime un double processus d'institutionnalisation. D'un côté, les IG ont incité la valorisation des territoires et de leur identité, avec, dans certains cas, la création d'obstacles aux innovations qui pourraient mettre en péril la typicité des produits. De l'autre, les IG ont été ajustées, dans le cadre d'un processus d'appropriation sectorielle, pour permettre des innovations techniques et organisationnelles jugées nécessaires pour que les producteurs puissent réagir à la perte de compétitivité sur les marchés nationaux et internationaux. Ainsi, dans un contexte d'hybridation des stratégies compétitives sur le marché du vin, les projets concilient des modèles conceptuels autrefois antagonistes. Pour cela, plus que concilier tradition et innovation, les IG créent des nouveaux compromis entre des principes de valorisation (définitions de qualité), qui se matérialisent dans un ensemble de changements des pratiques productives impliquant notamment le choix des cépages ou la définition des méthodes de vinification parmi d'autres composants. Nous avons étudié sept IG distinctes au Brésil (Vale dos Vinhedos, Pinto Bandeira, Monte Belo Sul, Farroupilha, Garribaldi) et en France (Beaujolais, Languedoc) sur la base d'entretiens semi-directifs, d'observation et d'analyse documentaire.

The concept of gender becomes significant when associated with variable and unpredictable effects of climate change. It is important to assess the linkages and outcomes between humans and their environment. I highlight the level of vulnerability and burdens on the different genders and discuss how these environmental influences are shifting what we will considered “traditional” social norms and responsibilities within rural households of Kenya and Tanzania. For agricultural and pastoral communities in eastern Africa, drought triggers many socio-economic alterations that lead to great shifts in traditional roles and daily duties especially for women. The key focus of this study relies on changing gender dynamics as a result of intensified and prolonged episodes of drought, considering male and female interactions and coping strategies. Using my case study of Ayalaliyo, Tanzania as a springboard, I will be analyzing women’s vulnerability, increased workloads, health implications, and alternative incomes as well as male disempowerment in the rural communities of Kenya and Tanzania. I aspire to find the connections between women and the environment and detect whether or not there have been similar changes in gender roles as a result of climatic changes throughout the rest of East Africa’s farming communities. I will be concluding by tying these effects to a more global perspective on the importance of gendering climate change adaptations.