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Concern about feeding an ever increasing population has long been one of humankind’s most pressing problems. This has been addressed throughout history by introducing into farming systems changes allowing them to produce more per unit of land area. However, these changes have also been linked to negative effects on the socio economic and environmental sphere, that have created the need for an integral understanding of this phenomenon. This thesis describes the application of learning machine methods to induct a relationship between the spectral response of farms’ land cover and their intensification levels from a sample of farming of Urdaneta municipality, Aragua state of Venezuela. Data collection like this is a necessary first steep to implement cost-effective methods that can help policymakers to conduct succesful planing tasks, especially in countries such as Venezuela where, in spite of there being areas capable of agricultural production, nearly 50% of the internal food requirements of recent years have been satisfied by importations. In this work, farm intensification levels are investigated through a sample of farms of Urdaneta Municipality, Aragua state of Venezuela. This area is characterised by a wide diversity of farming systems ranging from crop to crop-livestock systems and an increasing population density in regions capable of livestock and arable farming, making it a representative case of the main tropical rural zones. The methodology applied can be divided into two main phases. First an unsupervised classification was performed by applying principal component analysis and agglomerative cluster methods to a set of land use and land management indicators, with the aim to segregate farms into homogeneous groups from the intensification point of view. This procedure resulted in three clusters which were named extensive, semi-intensive and intensive. The land use indicators included the percentage area within each farm devoted to annual crops, orchard and pasture, while the land management indicators were percentage of cultivated land under irrigation, stocking rate, machinery and equipment index and permanent and temporary staff ratio, all of them built from data held on the 1996- 1997 venezuelan agricultural census. The previous clusters reached were compared to the ones obtained by applying the learning machine method known as self-organizing map, which is also an unsupervised classification technique, as a way to confirm the groups’ existence. In the second stage, the learning machine known as kernel adatron algorithm was implemented seeking to identify the intensification level of Urdaneta farms from a landsat image, which consisted of two sequential steps: namely training and validation. In the training step, a predetermined number of instances randomly selected from the data set were analysed looking for a pattern to establish a relationship between the label and the spectral response in an iterative process which was concluded when the machine found a linear function capable of separating the two classes with a maximum margin. The supervised classification finishes with the validation in which the kernel adatron classifies the unseen samples by using a generalisation of the relationships learned while training. Results suggest that farm intensification levels can be effectively derived from multi-spectral data by adopting a machine learning approach like the one described.

Computerised integrated models from science contribute to better informed and holistic exante integrated assessments of multifaceted policies and technologies. This view has lead to considerable effort being devoted to developing integrated models to support decisionmaking under Integrated Water Resources Management (IWRM). Nevertheless, an appraisal of previous and ongoing efforts to develop such decision support systems shows that attempts to address the hydro-socio-economic effects on livelihoods have been deficient and fragmented. To date, no universal standard integration method or framework is in use. Existing integrated models application failures have pointed to the lack of stakeholder participation. In an endeavour to close this gap, this thesis focuses on an integrated model development with prediction capability, ICHSEA, developed in Avenues script language in ArcView 3.3, to take advantage of the mapping capability of ArcView. This model couples existing hydrology (SWAT), agronomy (PARCHED-THIRST) and socio-economic (OLYMPE) models to link livelihoods of resource-constrained smallholder farmers to water resources availability at catchment level in the semi-arid Olifants subbasin, South Africa. These three models were calibrated and validated using observed data and local stakeholder participation, prior to coupling in the integrated model. All the models performed well in representing the study conditions, as indicated by the statistical performance. The integrated model is generally applicable to any catchment. The study methodology was inspired by the need to enhance rural livelihoods and to close the gap of stakeholder involvement in building and applying integrated models to ensure acceptability and application in decision-making. Over 20 years, the predicted impacts of untied ridges and planting basins versus conventional rainfed tillage on surface runoff reduction were 14.3 % and 19.8 %, respectively, and about 41─46 % sediment yield reduction in the catchment. At 90 % confidence interval, family savings improved from US$ 4─US$ 270 under conventional rainfed to US$ 233─US$ 1 140 under supplemental irrigation. These results underscore the economic and environmental benefits that could be achieved by adopting the new crop management practices. A relationship between maize crop evapotranspiration and family savings under different crop management strategies was also derived for five farm typologies in the catchment.

Le changement climatique menacera probablement la durabilité de la plupart des systèmes agricoles en région méditerranéenne et notamment au sud de la méditerranée. Le comportement des systèmes agricoles sera différent selon les régions sur la base de contextes biophysique, socio-économique, institutionnel et politique. L'objectif de cette thèse est d'analyser la résilience et la capacité d'adaptation au changement climatique des exploitations agricoles en prenant comme référence celles de la Basse Vallée de Medjerda (Nord de la Tunisie). Pour répondre à cet objectif, trois questions principales sont successivement abordées. Le premier chapitre décrit, en se basant sur une large revue de littérature, les effets agri environnementaux du changement climatique en région méditerranéenne et particulièrement en Tunisie. Le deuxième chapitre analyse les effets potentiels du changement climatique sur la résilience des exploitations agricoles de la Basse Vallée de Medjerda (BVM). Pour faire bref, la résilience d'une exploitation est sa capacité à assurer par elle-même sa viabilité économique et par conséquent sa pérennité. Pour ce faire, un cadre conceptuel a été construit. Ce cadre est basé sur trois étapes impliquant la définition de l'échelle spatiale, les forces exogènes, les indicateurs et les seuils de persistance. A cet effet, une chaîne de modèles biophysique-socioéconomique au niveau régional a été utilisée pour simuler l'effet du changement climatique d'une part sur les rendements des cultures et sur la salinité du sol à l'échelle de la parcelle, et d'autre part sur la résilience et la capacité d'adaptation des exploitations agricoles. Cette approche quantitative permet la simulation de stratégie d'adaptation agricole système en calculant trois indicateurs : le stock de terres, le stock de main-d'œuvre et le flux des revenus, en réponse au changement climatique. Le troisième chapitre évalue les stratégies d'adaptation possibles permettant de faire face aux effets du changement climatique. Ces stratégies ont été identifiées dans le cadre d'une approche participative, en concertation avec les agriculteurs et les experts locaux au niveau de la BVM et simulées en utilisant la chaîne de modèles. Les résultats de cette étude montrent une hétérogénéité des comportements des exploitations agricoles en fonction de la diversité et du degré d‘intensification des activités de production agricoles (végétale et animale). Les exploitations agricoles les plus diversifiées et les moins intensifiées avec une activité animale importante semblent être plus résilientes au changement climatique que les exploitations spécialisées ayant un système de production intensif. Nous constatons que les stratégies d'adaptation basées sur l'augmentation des doses d'irrigation pour satisfaire les besoins croissants en eau des cultures, l'irrigation de complément des céréales, et l'amélioration de l'efficience des systèmes d'irrigation améliorent la résilience des exploitations agricoles de la Basse Vallée de Medjerda. Ces stratégies ont un effet plus important sur la profitabilité des exploitations agricoles si elles sont accompagnées par une tarification d'eau binôme. Les résultats de cette étude montrent que les systèmes agricoles peuvent s'adapter au changement climatique de différentes façons. La méthodologie utilisée peut être adaptée à d'autres régions de la Méditerranée et permettra d'aider les experts et les décideurs politiques à proposer et tester des stratégies d'adaptation au changement climatique dans ces régions. / Climate change would impact sustainability of most agricultural systems in the Mediterranean region and particularly in the south of the Mediterranean. It is expected that agricultural systems react differently depending on biophysical, socioeconomic and political contexts of each agriculture. The objective of this thesis is to analyze the resilience and adaptive capacity to climate change of the farming systems of the Low Valley of Medjerda (Northern Tunisia). To meet this objective, three main steps are developed. The first chapter describes, based on a literature review, the agri-environmental effects of climate change in the Mediterranean region and particularly in Tunisia. The second chapter analyzes the potential impact of climate change on the resilience of the farming systems in the Low Valley of Medjerda (LVM). To do this, an operational Framework was built. The third chapter assesses the possible adaptive strategies to cope with the effects of climate change. These strategies have been identified through a participatory approach, in consultation with farmers and local experts in the LVM watershed. For this purpose, a chain of regional biophysical-socio-economic models was used to simulate the effect of climate change, on crop yields and soil salinity at field scale, and on the resilience and adaptability of farming systems. The results of this study show heterogeneous behaviors of farming systems depending on the diversity and the degree of intensification of agricultural production (crop and livestock). More diversified and less intensified farming systems with a large animal activity seem to be more resilient than specialized farms with intensive production system. In addition, as expected, we find that adaptation strategies based on the increasing of irrigation doses to meet the increased crop water requirements (SIrr.am), supplemental irrigation of cereal (SIrr.c) and the improvement of the efficiency of irrigation systems (SIrr.sys)improve the resilience of farming systems in the LVM watershed. These strategies have a greater effect on the profitability of farming systems if they are accompanied by a binominal water tariff. The methodology used in this research can be adapted for other Mediterranean regions and assist experts and policy makers to propose and test strategies for adapting to climate change in these regions.

In Vietnam, the research and application of biogas technology were given a considerable attention in past 30 years. There is several biogas plant models apply in the suburban and rural areas where most people’s life is based on animal husbandry. Each biogas plant model own strong points or weakness that adapt to detail circumstances. The biogas plants play a key role within the VACB farming system especially in the Mekong Delta where produce more than 50% of yearly national agriculture production. This paper gives a comprehensive overview on the popular biogas models in the Mekong Delta through its development history. Knowing on the presented biogas technology in the Mekong Delta will lead the biogas-related organizations or private on biogas development at this region. / Ở Việt Nam việc nghiên cứu và ứng dụng công nghệ khí sinh học đã được chú ý trong 30 năm gần đây. Một số mô hình khí sinh học đã và đang được lắp đặt tại các vùng ngoại ô và nông thôn là những nơi tập trung nhiều hộ dân chăn nuôi heo. Có nhiều mô hình khí sinh học đã được triển khai, trong đó mỗi mô hình đều có những điểm mạnh và điểm yếu đáp ứng theo từng yêu cầu cụ thể. Ở ĐBSCL nơi sản xuất trên 50% sản lượng nông nghiệp của cả nước, hầm ủ khí sinh học đóng một vai trò quan trọng trong mô hình canh tác VACB. Bài báo này trình bày chi tiết các kiểu hầm ủ khí sinh học phổ biến tại ĐBSCL tương ứng với từng thời điểm phát triển của công nghệ này. Sự hiểu biết về các kiểu hầm ủ khí sinh học hiện tại ở ĐBSCL sẽ giúp các tổ chức hoặc cá nhân có liên quan trong việc định hướng phát triển công nghệ khí sinh học cho toàn vùng.

Thesis (MA)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

Rural agriculture in Mlondozi, as for South Africa, is has a low productivity, which is the result of poor knowledge, information, beliefs and land tenure which limits the acquiring of loans for inputs. A LandCare Project was conducted for four years. Training was in the form of farmer managed research demonstrations which included the taught Conservation agriculture farming system which they compared to the Traditional farming system. Eighteen farmers initially joined the program and their soils were monitored for four years. At the end of the project undisturbed soil samples were taken from their fields where maize was cultivated following no-till (NT) farming system, and the conventional tillage system (CT). The soils from the two farming systems were compared using a laboratory rainfall simulator for run-off, erosion and infiltration. Each storm event in the rainfall simulator lasted for a period of 110 minutes (50 rotations). There were two statistical analyses done on the results. The first was a t-test was applied to the data to test for differences between the two systems, with a sample size of 72, at 18 sights with 4 replicates, except for carbon which was 36 analyses for the 18 sights. There was a significantly higher soil loss for NT soils for storm 1, compared to the CT soil, and a non significant difference for run-off for storms 1 and 2. Infiltration was significantly lower for the NT soil for the first storm, and not significantly higher for the NT soil for the second storm. The CT soils had a significantly higher infiltration rate for the first 16 rotations. After 68 minutes (rotation 34) the NT soils infiltration rate was higher. For simulated storm 2 the CT soils had a slightly higher infiltration rate up to 32 minutes (16 rotations) where after NT soils had a higher infiltration rate. Between 48 and 80 minutes (rotations 24 and 40) the NT soils had a significantly higher infiltration rate. From the results it can be concluded that the NT soils maintained the aggregate stability far longer than the CT soils. The initial and final infiltration rates were compared for the NT and CT soils for the simulated storms 1 and 2. The CT soils’ initial and final infiltration rate was similar, while the NT soils had a higher initial and final infiltration rate for the second storm, due to the soils settling with the first storm. The results question current literature that states that sealing of soils is a permanent feature. The carbon content of the NT soils was not significantly higher than the CT soils, which corresponded with the results. / Dissertation MInst (Agrar)--University of Pretoria, 2014 / gm2015 / Plant Production and Soil Science / MInst (Agrar) / Unrestricted

京都大学 / 新制・論文博士 / 博士(地球環境学) / 乙第13493号 / 論地環博第16号 / 新制||地環||44(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 舟川 晋也, 教授 西前 出, 准教授 真常 仁志, 教授 樋口 浩和 / 学位規則第4条第2項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

In Vietnam, the research and application of biogas technology were given a considerable attention in past 30 years. There is several biogas plant models apply in the suburban and rural areas where most people’s life is based on animal husbandry. Each biogas plant model own strong points or weakness that adapt to detail circumstances. The biogas plants play a key role within the VACB farming system especially in the Mekong Delta where produce more than 50% of yearly national agriculture production. This paper gives a comprehensive overview on the popular biogas models in the Mekong Delta through its development history. Knowing on the presented biogas technology in the Mekong Delta will lead the biogas-related organizations or private on biogas development at this region. / Ở Việt Nam việc nghiên cứu và ứng dụng công nghệ khí sinh học đã được chú ý trong 30 năm gần đây. Một số mô hình khí sinh học đã và đang được lắp đặt tại các vùng ngoại ô và nông thôn là những nơi tập trung nhiều hộ dân chăn nuôi heo. Có nhiều mô hình khí sinh học đã được triển khai, trong đó mỗi mô hình đều có những điểm mạnh và điểm yếu đáp ứng theo từng yêu cầu cụ thể. Ở ĐBSCL nơi sản xuất trên 50% sản lượng nông nghiệp của cả nước, hầm ủ khí sinh học đóng một vai trò quan trọng trong mô hình canh tác VACB. Bài báo này trình bày chi tiết các kiểu hầm ủ khí sinh học phổ biến tại ĐBSCL tương ứng với từng thời điểm phát triển của công nghệ này. Sự hiểu biết về các kiểu hầm ủ khí sinh học hiện tại ở ĐBSCL sẽ giúp các tổ chức hoặc cá nhân có liên quan trong việc định hướng phát triển công nghệ khí sinh học cho toàn vùng.

L’amélioration du bien-être des vaches laitières est un réel enjeu face aux attentes sociétales. Cette thèse a pour objectifs d’identifier (i) les aspects les plus dégradés du bien-être des vaches, (ii)les indicateurs de risque et (iii) les facteurs associés à l’atteinte de la relation homme-animal. Ce projet repose sur une étude épidémiologique utilisant la méthode Welfare Quality R pour évaluer le bien-être des vaches. En général, les boiteries étaient peu fréquentes et les animaux avaient une bonne liberté de mouvement. L’absence de faim et de soif et l’expression des comportements étaient bien respectés mais variables entre élevages. Le confort de couchage, l’absence de blessures et de maladies, le comportement social, l’état émotionnel et la relation homme-animal étaient dégradés et variables. L’écornage était souvent réalisé sans antidouleurs. Les principaux indicateurs de risque pour le bien-être des vaches sont la localisation géographique (pour la soif), la race (faim,comportement social), le logement (confort de couchage, blessures), l’interaction logement-race (état émotionnel) et localisation géographique-système de traite (expression des comportements propres à l’espèce). La mise en place de plan d’actions doit donc tenir compte du type d’élevage. Aucune association entre le système d’élevage et la relation homme animal n’a été trouvée. Les conditions de vêlage, les représentations des éleveurs et le comportement social des vaches étaient par contre associés à ce critère. De plus, de fortes variations entre vaches ont été relevées, suggérant que le tempérament des animaux joue un rôle important. / Improving dairy cows’ welfare is a major challenge in response to citizen concerns. The present thesis aimed to identify (i) major welfare problems, (ii) which farm characteristics are associated with the impairment of welfare and (iii) which factors are associated with the impairment of human-animal relationships. We conducted an epidemiological survey and used the Welfare Quality R protocol to assess dairy cows’ welfare. In general, prevalence of lameness was low and cows had opportunities to walk. The absence of hunger and thirst and the expression of species-specific behaviors were achieved but variable between farms. Resting comfort, skin injuries, health, social behavior, cows’ emotional state and human-animal relationships were affected and variable. Disbudding was often performed without pain relief. The main risk indicators of poor cow welfare were farm location (for thirst), breed (hunger, social behavior), housing (resting comfort and skin injuries), the interaction housing-breed (emotional state) and location-milking system (expression of species-specific behaviors). Action plans should be designed according to farm types. The quality of the human-animal relationship was not associated with farm main characteristics, but to calving conditions, farmers’ attitudes and cows’ social behavior. In addition, we observed large variations between-cows in their responses to humans, suggesting that individual behavioral traits of cows play a major role.