Dans les pays en voie de développement, les agriculteurs sont très dépendants des arbres pour offrir une grande diversité de produits tels que des outils, de la nourriture, des médicaments, du bois de chauffage et de construction. Les arbres offrent ainsi un grand potentiel socioéconomique et environnemental pour les paysans. Par contre, malgré leurs usages multiples, les arbres fruitiers semblent être une des cultures ayant le moins d'incidence dans le revenu familial depuis la crise du café des années 1980, dans les Hauts-Plateaux de l'Ouest du Cameroun. Nous nous sommes demandé quelles étaient les principales contraintes et opportunités des paysans pour l'intégration et l'entretien des arbres fruitiers dans leurs systèmes de culture afin de connaître les aspects à favoriser pour augmenter le revenu des paysans à l'aide des arbres fruitiers en systèmes agroforestiers. Pour ce faire, nous avons entrepris une méthodologie participative. Un premier groupe de discussion avec les délégués d'arrondissement, des chefs de poste et quelques paysans clés nous a permis d'identifier les dix villages où la recherche a eu lieu afin d'obtenir une vision globale de l'état des arbres fruitiers dans le département de la Menoua. Dans chaque village, un groupe de discussion ainsi que des enquêtes auprès des agriculteurs étaient planifiés, pour connaître les caractéristiques de l'exploitation agricole et du ménage. Les résultats nous permettent de décrire les caractéristiques des systèmes agrisylvicoles dans la Menoua, les produits et services fournis par les arbres et leurs apports socioéconomiques. Les arbres fruitiers les plus importants économiquement parlant dans la Menoua sont l'avocatier, le colatier et le safoutier. Les arbres fruitiers sont utiles aux paysans, comme nourriture dans les champs ainsi que dans la pharmacopée traditionnelle et ils peuvent combler jusqu'à 20% du revenu des ménages de la Menoua. Les fruitiers pourraient donc être une option favorable à la diversification des revenus des paysans pour le développement socio-économique de la région de l'Ouest du Cameroun.

Expanding urbanization, characterized by increased impervious surfaces and decreased tree canopy, is contributing to rising urban temperatures. This trend has implications for energy consumption, which strategically placed trees can modify by casting shade upon building and ground surfaces. However, urban densification, a paradigm of modern residential land development, often constrains space for planting shade trees. Thus, the overall objective of this dissertation was to investigate shade tree planting strategies and their effects on residential cooling and heating energy conservation for dense urban neighborhoods in U.S. cities on a latitudinal gradient. The first study used a computer program called Shadow Pattern Simulator to examine the effects of tree form, tree placement, and sunlight exposure on shade provision for a residential structure model. Simulation results affirmed the conventional strategy in northern latitudes that recommends planting shade trees on the east or west aspect for maximizing beneficial shade while avoiding tree plantings on the south aspect to minimize any heating penalty of undesirable shade. However, in southern latitudes, planting trees on southerly aspect should not be discounted because the shorter heating season lessens the detrimental heating penalty while providing beneficial season shade. The second study, using an energy simulation program called EnergyPlus, evaluated the effect of a single shade tree upon the energy consumption of the structure model. This study affirmed that energy conservation benefits are influenced by the quantity as well as the quality of tree shade upon building surfaces. In addition, interactions between sun angle, tree form, and tree placement were observed to influence tree shade effects on annual energy consumption. In the third study, based on the first two studies, an alternative tree placement strategy, which reconfigured tree placement around the residential structure, was developed to maximize cooling and heating energy savings while attenuating space conflicts. The alternative strategy was found to be as effective as the conventional strategy while being more responsive to parcel or building orientations in dense urban neighborhoods. Overall, understanding the fundamental interactions between tree form, tree placement, and geographic settings is critical for improving energy conservation benefits of shade trees in dense urban settings. / Ph. D.

Recycling felled urban trees that are hazardous or unhealthy is increasingly viewed as a viable practice to control disposal costs, promote environmental practices, and support local commerce. Wide spread waste wood utilization is encumbered by numerous presumptions about wood quantity, quality, accessibility, and presence of foreign objects; yet there is almost no scientific literature about these presumptions. Without this knowledge, informed decisions cannot be made about the viability of waste wood utilization. In this study, we assessed the quality and quantity of timber in street trees scheduled for routine removal by the District of Columbia (the District) using a modified timber grading protocol adapted from the United States Forest Service. We developed a second protocol to assess the feasibility of timber salvage by identifying physical barriers commonly encountered in urban areas (e.g., high volume traffic, utilities around the tree, and infrastructure). The randomized sampling scheme was stratified by land-use zones and focused on the six most abundant tree species: Acer platanoides, Acer rubrum, Acer saccharum, Quercus palustris, Quercus phellos, Quercus rubra. Our findings suggest the majority of condemned street trees are of too poor quality to contain timber (58% cull rate); however, trees that contain merchantable logs are likely to be easily removed. A notable discovery that could prove problematic for wood salvage was that the majority of trees (88%) contained superficial metal items embedded in the trunk surface. Furthermore, presence or absence of a merchantable-sized log (p=0.0445) depended on the tree's species, as did the average volume observed (p<0.0001). Additionally, land-use zones had an effect on the removal feasibility scores (p=0.0257) but had no effect on log presence or log volume. Throughout the District, we estimated that 36,500 board feet of merchantable logs are generated from routine removals of our top six species annually. These findings provide empirical data pertaining to urban timber salvage, which might aid decisions on the investment worthiness of utilizing urban street trees. / Master of Science

L’arboriculture de la Moyenne Vallée du Rhône, concurrencée par les pays à faible coût de production, subit une importante crise structurelle. Dans ce contexte, nous interrogeons les liens existants entre l’arboriculture et ses territoires. Ils peuvent en effet constituer des ressources mobilisées par les acteurs locaux pour développer des formes de valorisation territoriale.Le modèle productif historique de l’arboriculture de la Moyenne Vallée du Rhône, celui de bassin de production-expédition, est aujourd’hui remis en question par deux tensions opposées. La première, dite « centrifuge », est exercée par les principaux expéditeurs qui élargissent leur aire d’approvisionnement au-delà de celle du bassin de production pour être capables d’offrir des volumes de fruits standardisés satisfaisant à la demande des grands distributeurs. A l’inverse, un ensemble de tensions « centripètes » produisent un effet de morcellement interne au bassin, résultant des initiatives d’identification territoriale des fruits portées par les producteurs. A l’intersection de ces tensions, les arboriculteurs développent des stratégies pour maintenir la viabilité économique de leurs exploitations. La tendance est d’ajouter aux circuits d’expédition existants de nouveaux débouchés qui valorisent plusieurs proximités entre production et consommation. Nous décrivons ainsi des « circuits de proximité » pluriels et multi-scalaires, où interviennent différents types de professionnels (grossistes, détaillants, IAA), de consommateurs (habitants ou plus éloignés) et de modes de commercialisation. S’articulant entre concurrence et complémentarité au bassin de production-expédition, ces circuits bénéficient de soutiens de la part des collectivités territoriales. La conclusion de la thèse propose une caractérisation des différents circuits de proximité ainsi qu’un cadre théorique pour penser la diversité des formes de valorisation territoriale en agriculture. / The fruit growing sector in the Middle Rhône Valley, competed by low-cost-production countries, faces a serious structural crisis. Then, we analyze the links between the arboriculture and its territories which can constitue resources mobilized as territorial valorization forms by local actors.The historic productive model of the arboriculture in the Middle Rhône Valley, the production-shipping basin, is now questioned by two rival forces. The first, called « centrifugal », is exercised by the main shippers who enlarge their supply area to be able to deliver large volumes of standardized fruits, relevant for the main retailers demand. In the opposite, some « centripetal » forces produce a fragmentation effect in the basin. These result from territorial identification initiatives for fruits, lead by the producers.Between these forces, farmers develop some strategies to maintain economic viability of their farms. They add to the existing shipping-circuits news outlets which valorize various proximities between production and consumption. We describe multi-scale « proximity circuits », including different types of the fruits supply chain actors, of consumers and marketing chanels. These circuits are shaped by competition and complementarity relationships with the basin of production-shipping. They benefit from the local communities supports.The conclusion of the research displays a characterization of the different proximity circuits and a theorical model to analyze the diversity of territorial valorization forms in agriculture.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-09-23T17:10:47Z No. of bitstreams: 2 Dissertação_Michelly-1.pdf: 1003558 bytes, checksum: f7289e1224355e7fb4cda6571653c74c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-23T18:33:16Z (GMT) No. of bitstreams: 2 Dissertação_Michelly-1.pdf: 1003558 bytes, checksum: f7289e1224355e7fb4cda6571653c74c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-23T18:33:16Z (GMT). No. of bitstreams: 2 Dissertação_Michelly-1.pdf: 1003558 bytes, checksum: f7289e1224355e7fb4cda6571653c74c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In order to evaluate the quality and quantity of tree species planted in the cities of MS: Cassilândia (CA) and Paranaíba (PA), with the lowest PIB; Chapadão South (CH) and Costa Rica (CO), with higher PIB a survey of tree species present in 30 blocks of each of these cities was done. Trees were identified and recorded information such as: plant health; planting site; pruning; trees under power lines, tree size, position on the sidewalk; origin; outer root condition and existence of sidewalks. Shannon’s diversity index and Pielou’s evenness index was calculated. To analyze the structural and floristic similarity, the Jaccard and Morisita’s indexes was employed. Found 3180 individuals belonging to 100 species of 40 families, with CA, CH, CO and PA had 838, 1130, 657 and 555 individuals respectively. Shannon’s index was 2.08 overall. Jaccard’s index was 45%, cities with higher PIB and a lower PIB were more similar to each other. Morisita’s similarity index showed structural similarity between cities, ranging between 0.82 and 0.99. About the position on the sidewalk, the cities with the highest PIB had a number of trees above and below expectations at the curb and center, respectively. Otherwise, cities with the lowest PIB showed opposite results. By ANOVA test, CA, CH and PA were different, CH showed an average number of trees significantly larger and PA, a smaller number. The cities with the highest PIB had a number of trees higher than expected for individuals without any conflict with sidewalks and below expectations for those who had some type of conflict. Already the cities with the lowest PIB showed opposite results. About the origin, the cities with the highest PIB had a number of exotic individuals above the expected, native from Brazil less than expected, since the native Cerrado had a higher number than expected. The cities with the lowest PIB showed opposite results. The most abundant species throughout the survey was Licania tomentosa (oiti), totaling 1879 individuals (59%), representing in CA, CH, CO and PA, 85%, 36%, 57% and 66% respectively. Exotic species totaled 68%, while 22% are native from Brazil and 4% are Cerrado’s native. Among the 3180 individuals found: 80% were planted in front of homes, 14% in other places, such as churches, schools, kindergartens, clinics, and other 6% in front of business establishment. Concerning the plant health, 81% of the total were in good condition, 17% in satisfactory condition, and 2% in poor condition, 44% are free and 56% are under the power lines, of which 10% had conflict. As for pruning, 75.4% of sampled trees exhibited correct pruning, 9.5% incorrect, 12% nonexistent and 2.6% radical. The cities with the highest PIB showed greater wealth than those with lower PIB, and greater arboreal suitability in various aspects. Moreover, there is excessive use of exotic species and not appropriate species, due the large size. / Com o objetivo de avaliar comparativamente a qualidade e quantidade das espécies arbóreas plantadas nos municípios de Mato Grosso do Sul (MS): Cassilândia (CA) e Paranaíba (PA), com menor Produto Interno Bruto (PIB); Chapadão do Sul (CH) e Costa Rica (CO), com maior PIB, foi realizado um levantamento das espécies arbóreas presentes em 30 quadras de cada cidade. Os indivíduos arbóreos foram identificados e registradas informações como: fitossanidade; local do plantio; poda; árvores sob rede elétrica; porte arbóreo; posição na calçada; origem; condição externa da raiz e existência de calçamento. Foram calculados o índice de diversidade Shannon e o índice de equabilidade de Pielou. Para analisar a similaridade florística e estrutural, foram empregados os índices de Jaccard e de Morisita. Foram encontrados 3180 indivíduos, pertencentes a 100 espécies de 40 famílias, sendo que CA, CH, CO e PA apresentaram, respectivamente, 838, 1130, 657 e 555 indivíduos. O índice de Shannon total foi de 2,08. O índice de Jaccard foi de 45%; as cidades com maior PIB e as com menor PIB foram mais semelhantes entre si. O índice de similaridade de Morisita mostrou similaridade estrutural entre as cidades, variando entre 0,82 e 0,99. As cidades com maior PIB tiveram um número de árvores acima e abaixo do esperado no meio-fio e no centro da calçada, respectivamente. Já as cidades com menor PIB mostraram resultados opostos. Pelo teste de ANOVA, CA, CH e PA foram diferentes entre si; CH apresentou um número médio de árvores significativamente maior e PA, um número menor. As cidades com maior PIB tiveram um número de árvores acima do esperado para os indivíduos sem nenhum tipo de conflito com as calçadas e abaixo do esperado para aqueles que apresentaram conflito. Já as cidades com menor PIB mostraram resultados opostos. Com relação à origem, as cidades com maior PIB tiveram um número de indivíduos exóticos acima do esperado, nativas do Brasil menor que o esperado; já as nativas do Cerrado tiveram um número maior que o esperado. As cidades com menor PIB mostraram resultados contrários. A espécie mais abundante foi Licania tomentosa (oiti), totalizando 1879 indivíduos (59%), representando em CA, CH, CO e PA, 85%, 36%, 57% e 66%, respectivamente. Espécies exóticas totalizaram 68%, enquanto 22% são nativas do Brasil e 4% são nativas do cerrado. Dos 3180 indivíduos encontrados: 80% foram plantadas em frente às residências, 14% em outros locais, como igrejas, escolas, creches, consultórios, entre outros e 6% em frente a estabelecimentos comerciais. Quanto à fitossanidade, 81% do total encontravam-se em boas condições, 17% em condições satisfatórias e 2% em condições ruins; 44% encontram-se livre e 56% estão sob a fiação elétrica, dos quais 10% apresentaram conflito. Quanto à poda, 75,4% das árvores amostradas apresentaram poda correta, 9,5% incorreta, 12% inexistente e 2,6% radical. As cidades com maior PIB apresentaram maior riqueza do que as com menor PIB, e uma maior adequação em vários aspectos. Além disso, há um uso excessivo de espécies exóticas e espécies não apropriadas, em virtude do porte elevado.

L'arboriculture de la Moyenne Vallée du Rhône, concurrencée par les pays à faible coût de production, subit une importante crise structurelle. Dans ce contexte, nous interrogeons les liens existants entre l'arboriculture et ses territoires. Ils peuvent en effet constituer des ressources mobilisées par les acteurs locaux pour développer des formes de valorisation territoriale. Le modèle productif historique de l'arboriculture de la Moyenne Vallée du Rhône, celui de bassin de production-expédition, est aujourd'hui remis en question par deux tensions opposées. La première, dite " centrifuge ", est exercée par les principaux expéditeurs qui élargissent leur aire d'approvisionnement au-delà de celle du bassin de production pour être capables d'offrir des volumes de fruits standardisés satisfaisant à la demande des grands distributeurs. A l'inverse, un ensemble de tensions " centripètes " produisent un effet de morcellement interne au bassin, résultant des initiatives d'identification territoriale des fruits portées par les producteurs. A l'intersection de ces tensions, les arboriculteurs développent des stratégies pour maintenir la viabilité économique de leurs exploitations. La tendance est d'ajouter aux circuits d'expédition existants de nouveaux débouchés qui valorisent plusieurs proximités entre production et consommation. Nous décrivons ainsi des " circuits de proximité " pluriels et multi-scalaires, où interviennent différents types de professionnels (grossistes, détaillants, IAA), de consommateurs (habitants ou plus éloignés) et de modes de commercialisation. S'articulant entre concurrence et complémentarité au bassin de production-expédition, ces circuits bénéficient de soutiens de la part des collectivités territoriales. La conclusion de la thèse propose une caractérisation des différents circuits de proximité ainsi qu'un cadre théorique pour penser la diversité des formes de valorisation territoriale en agriculture.

Thesis (MSc)--Stellenbosch University, 1968. / ENGLISH ABSTRACT: Trees are needed on the semi-arid Highveld of the western Transvaal for shelterbelts, woodlots, fodder, honey, shade and ornament. A brief history of tree planting in the area, more particularly at Lichtenburg and Potchefstroom, is given. Relatively few species can be grown successfully in the western Transvaal because of the unfavourable climate. Hot, dry winds blow almost continuously off the Kalahari between August and October before the first, spring rains; cold winds and frosts are experienced in winter, although the summers are hot; the rainfall is erratic and low, averaging about 600 mm. a year and occurring mainly in the form of heavy thunderstorms during summer; hail is common. The geology of the area is complex. In the north-west an overburden of wind-transported sand obscures the underlying formations. The soils are mostly of a light, sandy or loamy consistency, with a fairly high base-saturation value. Concretions, sometimes forming a continuous hardpan, are characteristic of certain types. Various indigenous trees are found in some localities. These are small,and are mainly confined to rocky hillsides and stream banks. In the past they have been much exploited for rough building timber, fence posts and firewood. Their growth is very slow, and exotics have proved to be more vigorous as well as more useful in cultivation. Possible adaptations of trees to dry climates are discussed. It is concluded that'apparent adaptations observed in the field are of little value in selecting trees for dry areas. No practical alternative therefore exists at this stage to the introduction of species from .areas with a similar climate and testing these under local conditions. Parts of the world having a climate similar to that of the western Transvaal are in.dicated. Summarised results of species trials in the western Transvaal are given in tabular form, and recommendations for tree planting in the area are made. In an appendix, trials of BB species in arboreta at Lichtenburg and Potchefstroom are fully described and discussed.

Arboricultural work is inherently dangerous, with more serious injuries and fatalities than most other professions. Safety standards exist in some jurisdictions, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) jurisdictions share standards. To establish a baseline understanding of these issues, my objectives were to (i) develop a database of existing standards, (ii) identify the most frequently occurring safety topics and (iii) describe similarities and differences in safety topics among standards from different countries. I worked with a variety of contacts and traditional university library resources to identify, obtain, analyze, and compare arboricultural safety standards from around the world. I established a database of standards and found that various types of standards exist among countries: most countries used locally developed standards and industry standards were the most common types of standards because of industry professional’s expertise in arboricultural work safety matters. I analyzed the contents of 4 areas of arboricultural work categories in standards: General safety requirements (GSR), personal protective equipment (PPE), chainsaw (CS) and tree climbing (TC). GSR and PPE categories had the most proportion of common safety topics as compared to CS and TC. I identified most common safety topics in all 4 categories which shed light onto some of the areas of safety practices which are commonly recognized as important, while least common safety topics suggest areas of arboricultural work that may or may not be useful in future revisions of standards. There were 7 groups of countries most similar in the types of standards which they use, suggesting that countries can influence one another in adopting safety practices and that there are regional and international cooperation between countries in developing standards. My findings can be used by safety committees around the world in developing standards, as well as for the ISA’s International Safety Committee (ISC) to initiate an international safety standard. This study is novel and a stepping-stone for future research in evaluating the effectiveness of standards in reducing arboricultural work incident rates.

Globe Group, a company under the brand Greenworks Tools, is one of the industry leaders in battery-powered outdoor equipment, developing tools that deliver the performance of a gasoline-powered tool without the hassle and emissions associated with it. Gasoline-powered tools are still prevalent in the field of arboriculture where arborists work daily with chainsaws while performing tree felling and pruning. Now a new type of chainsaw is in development by Globe Group which is characterized by its lightweight and large battery capacity, which brings extraordinary battery life. This feature is possible by redesigning the chainsaw to support an external battery, which is housed in a separate battery pack instead of placing the battery directly inside the tool. The aim of the project is to adapt and design the battery pack for arborists by using a user-centered design approach with focus on ergonomics. This is done by having a close cooperation with the arborists during the whole project, from pre-study to final concept evaluation, to explore and fulfill the needs of the user. By using a wide range of research and design methods, a final concept is developed to reach the needs of the user and company. / Globe Group, som står bakom varumärket Greenworks Tools, är branschledande inom batteridriven utomhusutrustning och levererar verktyg med samma prestandanivå som hos ett bensindrivet verktyg, fast utan utsläpp och krångel som det typiskt är förknippat med. Bensindrivna verktyg är fortfarande mycket vanliga inom trädvårdssektorn där arborister arbetar med motorsågar dagligen vid trädfällning och grenbeskärning. Nu är en ny typ av motorsåg under utveckling av Globe Group som kännetecknas av sin lätta vikt och stora batterikapacitet, vilket ger extra lång batterilivslängd. Denna kombination är möjligt genom att ha ett externt batteri vilket är huserat i ett separat batteripaket istället för att placera batteriet direkt in i verktyget. Projektets mål är att anpassa och konstruera batterifickan specifikt för målgruppen arborister genom att använda en användarcentrerad designapproach med fokus på ergonomi. Detta görs genom ett nära samarbete med arboristerna under hela projektets gång, från förstudie till utvärdering av resultat, för att utforska och uppfylla användarens behov. Ett slutligt koncept är utvecklat för att tillgodose både användarens och företagets behov/krav.

En 2009, le Grenelle de l’environnement a ouvert en France la possibilité d’intégrer des clauses environnementales au sein des cahiers des charges d’Indications Géographiques (IG). Cette opportunité nouvelle intéresse fortement les Agences de l’eau qui cherchent de plus en plus à agir en amont à la source des pollutions agricoles. Dans ce contexte, cette étude interroge la manière dont certaines démarches de qualité alimentaire intègrent dans leur dynamique des objectifs de préservation de l’eau. Pour y répondre, nous avons développé une approche globale permettant de resituer les enjeux de qualité de l’eau dans ceux plus larges d’environnement. Nous avons également dépassé la seule analyse des cahiers des charges des IG pour considérer l’ensemble des actions en faveur de l’environnement dans lesquelles elles s’impliquent. Le cadre d’analyse développé, celui de la résilience des Systèmes Alimentaires (SA) de qualité différenciée répond à ce besoin d’élargissement. Il nous permet d’étudier les dynamiques environnementales engagées pour faire face à des perturbations liées à la dégradation des ressources naturelles dont l’eau. Il s’agit autant de perturbations factuelles, mesurées, que de perturbations représentées lorsque les acteurs envisagent un risque potentiel. Ce cadre d’analyse a été appliqué à la viticulture et à l’arboriculture dans le Sud-Est de la France. Les résultats montrent la complexité des dynamiques environnementales engagées : elles reposent toutes sur plusieurs actions complémentaires et supposent la présence d’acteurs clés ayant la capacité à engager une dynamique collective et à envisager les SA à la fois dans leur dimension verticale les liant au marché et dans leur dimension horizontale les insérant dans le territoire. / In 2009, The Grenelle de l'Environnement (French environmental pact) introduced environmental clauses within Geographical Indications (GI) specifications. French Water agencies (agences de l’eau) perceive it as a good opportunity to address the issue of agricultural pollution, by takings actions at the upstream level. In this context, this study examines how certainfood quality processes are proactively setting targets for conserving water. This question led to develop a global approach in order to look at the issues of water quality from the wider angle of environmental preservation. It requires not only to focus on regulation tools of food quality products but also to take into account a larger set of environmental actions. Along the same lines, the theoretical framework of the resilience of food system of differentiated quality has also been developed. It allows to study proactive environmental dynamics set up by stakeholders to deal with perturbations linked to natural resources degradation, such as water. Those perturbations can be factual (measured) or represented, when stakeholders consider a potential risk. This analytical framework has been applied on case studies in viticulture and fruit production in the South-East of France. The results underscore the complexity of environmental dynamics: they are based on a set of complementary actions and require the mobilization of key players, able to engage in a collective dynamics but also to have a wider vision of food systems, both by looking at the vertical dimension (market oriented) and horizontal dimension (link with the local territory).