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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Unequal adaptation : socially differentiated responses to environmental change and food insecurity among smallholder farmers

Bailey, Meghan January 2017 (has links)
Achieving food security in a changing climate is one of the greatest challenges of the 21st century. For subsistence-oriented farming families who experience firsthand pressures on their food system - population growth, environmental degradation and climate change, to name only a few - adaptation has become an urgent necessity. The ability to 'adapt and benefit' through a suite of climate change adaptation interventions that build adaptive capacity is touted by many humanitarian and development institutions as integral to food security today. However, adapting and benefiting is often a far reach for many smallholder farming families, who more commonly manage multiple interdependent stressors through a mix of adaptive actions and negative coping strategies. The relative benefit of this mix of adaptive and coping strategies is socially differentiated, varying by location and both between and within households. This combination of strategies, or the variety of options to enact livelihood outcomes, is framed as a response space. This thesis explores the impact of social differentiation on the adaptive capacity of subsistence-oriented farming families experiencing food insecurity and environmental change. Using a case study of two villages in the Upper West region of Ghana, it investigates how adaptive capacity and response spaces differ based on points of social differentiation; the drivers that limit or exacerbate adaptive capacity and response spaces; and the implications of these responses for humanitarian, development, and government programmes that aim to support these populations. These questions are approached using mixed methods (embedded direct observation, the Women's Empowerment in Agriculture Index household and individual survey, participatory action research exercises, child growth and hospital admissions records, focus groups, and key informant interviews) and a unique conceptual framework which draws heavily from systems thinking, feminist research theory, Sen's capabilities approach and grounded theory. I followed context-specific local drivers to deeply examine the familial and cultural political lives of households to better understand the interdependent nature of empowerment within the household, the distribution of scarce food, control over livelihoods and income, the management of poverty-induced stress, and the risk these drivers pose to public health. Out of this research, a multi-level vulnerability landscape surfaced, characterized by a food system on the margins and unequal adaptation within the case study population. The research led to the following insights: farmers experience multiple disadvantages being located in the Upper West of Ghana as compared to southern regions, and are underserved by multiple governmental and NGO institutions; farmers in turn experience heterogeneous vulnerability and access to response spaces at the community level, which are deeply entrenched in social norms that favour adult male bodies, male spaces, and male-typical productive roles; and, at the same time, there are individuals and families that stand outside these trends and are able to adapt and benefit, which highlights the need for an intersectional approach when examining the household and sub-household context. The 2015 Sustainable Development Goals include a pledge to ‘leave no one behind' in the pursuit to 'free the human race from the tyranny of poverty and want and to heal and secure our planet'. Understanding the differing vulnerability of subsistence-oriented smallholder farming populations, as well as the ways their response spaces and adaptive capacity have been differently shaped, will be important for the program design and targeting strategies of interventions to achieve this goal. This thesis aims to contribute to this enormous task.
102

Revisiting patterns and processes of forest cover change in the tropics : a case study from southeast Mexico

Gueye, Kinne January 2018 (has links)
Vast progress has been made in detecting rates of tropical deforestation, yet the relationship between visible patterns of forest change, multi-scalar human processes and the underlying drivers associated with them is poorly understood. Building on satellite imagery, a household livelihood survey and semi-structured interviews, this research scrutinised changes of forest cover from the mid-1990s to 2015 in a municipality located in southeastern Mexico and investigated the proximate causes and underlying drivers of change at the household and community levels. Emerging evidence indicated that, contrary to the persistent narrative of deforestation for the region, forest cover change is highly dynamic including periods of deforestation and forest recovery. Moreover, a close examination of 24 communities showed forest cover gained terrain, while the agricultural frontier retracted. Drawing on a comparison between the household survey and previous analyses, it could be inferred that forest resurgence was produced by the decrease in the farming area and the increase in the abandonment of farming activities by some communities. Associated with the adaptation of households was the development of formal and informal institutions at the community level in response to macro-global forces linked to the implementation of forest conservation strategies, environmental degradation, market liberalization and increased urbanization. Overall, this research adds not only to our understanding of the complexity of land-use and cover change in emerging globalized economies but also exemplifies the spatial and temporal heterogeneity of tropical forest systems, which challenges partial models of deforestation and policies designed to reduce it. The research may be focused on a narrow region of the globe, nevertheless, the insights and recommendation provided may be useful to further forest conservation schemes in other tropical regions.
103

Export vegetable supply chains, household labour allocation and poverty effects among small producers – Evidence from Northern Tanzania

Benali, Marwan 14 November 2017 (has links)
No description available.
104

Pro-poor value chain governance in the mtateni irrigation scheme at Tugela ferry, Msinga, KwaZulu-Natal

Buthelezi, Thokozile Cynthia January 2013 (has links)
Magister Philosophiae - MPhil / This study explored value-chain governance in the Tugela Ferry Irrigation Scheme in KwaZulu-Natal, and presents data on input markets, vegetable production and output markets. Rural poverty is a major problem in post-apartheid South Africa, and smallholder agriculture has been identified by the Economic Development Department as a key component of its New Growth Path framework. Some scholars argue that since water is a scarce resource, irrigation farming should form a key focus of pro-poor land redistribution policy. The 1994 democratic dispensation saw the dismantling of the agricultural homeland parastatals which managed these schemes, causing them to collapse or near collapse. Yet they may have the potential to reduce rural poverty. While markets are key for viable production of fresh produce, some scholars assert that globally, input suppliers, food processors and supermarkets dominate the agro-food industry resulting in negative outcomes for smallholder producers. In South Africa, four major supermarkets (which together claim 55% of retail market share) were in the past located mainly in cities, but the trend now is that they are moving to small towns and townships. There are documented cases where pro-poor governance of fresh produce value chains has resulted in positive outcomes in South Africa. The re-governing markets concept which postulates that a multi-stakeholder approach to making the governance of agricultural value chains pro-poor, is offered as a solution to reducing poverty. This thesis argues that the incorporation of smallholder farmers into modern markets remains ineffective in dealing with poverty because it includes only a few smallholder farmers and those included face exclusion when they are exposed to harsh market conditions.
105

Pertinence de l’agriculture de conservation pour tamponner les aléas climatiques : cas des systèmes de culture en riz pluvial au lac Alaotra, Madagascar / Can conservation agriculture buffer climate hazard : the case of upland rice cropping systems in the Lake Alaotra region of Madagascar

Bruelle, Guillaume 19 December 2014 (has links)
En Afrique sub-saharienne (ASS), l'agriculture de conservation (AC) est diffusée afin de d'améliorer durablement la productivité de l'agriculture familiale. Cette AC est basée sur les principes de travail réduit du sol, d'une couverture permanente et de rotations introduisant des légumineuse. Parmi tous les bénéfices potentiels de l'AC, le mulch peut améliorer le bilan hydrique et tamponner le stress hydrique, et donc sécuriser les rendements, lorsque les pluies sont limitées et/ou aléatoirement distribuées. A Madagascar, la région du lac Alaotra connaît une forte expansion de la riziculture pluviale. Etant caractérisée par une distribution des pluies très erratique, la pratique de l'AC semble pertinente pour sécuriser la production pluviale. L'objectif de cette étude est donc d'évaluer dans quelle mesure cet aléa climatique est tamponné par l'AC. Tout d'abord, à travers revue de la littérature scientifique, nous avons ouvert à une problématique plus large. En effet, au regard des projections de croissance démographique et de changement climatique (CC) en ASS, l'AC est proposée comme solution ‘climate-smart' ; i.e. une agriculture capable d'augmenter la productivité et de s'adapter au CC tout en l'atténuant. Les études identifiées en ASS montrent une capacité de l'AC à augmenter les rendements sur le long-terme, et à plus court-terme dans les contextes climatiques où les pluies sont faibles et/ou mal distribuées. Cela suggère donc une capacité de l'AC à s'adapter au CC qui prévoit une augmentation de la variabilité de la distribution des pluies en ASS. La capacité de l'AC à atténuer le CC en séquestrant du carbone (C) dans les sols reste en suspens car le stockage du C se fait principalement en surface et la stabilité de ce C est questionnée. Nous nous sommes ensuite recentrés sur le sujet et la zone de cette étude afin d'évaluer le potentiel de l'AC à tamponner l'aléa pluviométrique. En se basant sur les données de suivi de parcelles en transition vers l'AC sur quatre saisons contrastées, nous avons constaté une augmentation des rendements moyens en riz pluvial dès la première année de pratique, avec une augmentation progressive des rendements et une diminution de la variabilité. Les données ont également suggéré une sécurisation des semis précoces et tardifs en AC. Nous avons constaté un poids important du climat sur la variabilité des rendements dans la zone d'étude. Cette analyse exploratoire nous a donc permis d'observer des effets positifs de l'AC dans le contexte climatique du lac Alaotra, suggérant notamment un effet potentiel sur la ressource hydrique. Mais les informations à notre disposition ne nous ont pas permis de vérifier cette hypothèse. Nous nous sommes donc intéressés à l'impact du mulch sur le bilan hydrique et les rendements en riz pluvial dans les conditions agro-climatiques de la zone d'étude. Nous avons effectué une expérimentation virtuelle, en utilisant le modèle PYE-CA. Nous avons confirmé la capacité du mulch à réduire le ruissellement. Nous avons identifié les dates de semis pour lesquelles le riz pluvial est le moins impacté par le stress hydrique dans la région. Les résultats nous ont indiqué que pour les dates de semis majoritairement pratiquées par les agriculteurs, et dans un éventail de conditions de sol, la disponibilité en eau est très peu affectée par une modification du ruissellement. Les bénéfices d'une réduction du ruissellement apparaissent dans des conditions hydriques plus stressantes telles que des dates de semis précoce ou une intensification, en diminuant la variabilité des rendements. Cette étude nous a permis de mieux appréhender les impacts de l'AC sur le bilan hydrique dans le contexte climatique de notre zone d'étude. Pour faire sens, ces résultats sont à intégrer à l'échelle exploitation, voire plus large, pour identifier les contraintes et avantages induits par les systèmes en AC dans le contexte socio-économique du lac Alaotra. / Conservation agriculture (CA) is widely disseminated at large scale in sub-Saharan Africa (SSA) in order to restore soil fertility and sustainably increase crop production of family farming. As defined by the FAO, CA is based on the three principles of minimal soil disturbance, permanent soil cover, and complex crop rotation. Among all the beneficial functions of CA, its ability to improve water balance through mulching can buffer water stress during crop cycle, and hence secure yields when rainfall are limited or poorly distributed. In the Lake Alaotra region of Madagascar, the area under rainfed upland rice has expanded lately. The region being characterized by an erratic rainfall distribution, intra- and inter-annually, CA practice seems appropriate to secure rainfed production. The main objective of this study is to evaluate to which extent this climate hazard can be buffered through the practice of CA. Firstly, we ran a review of the scientific literature to better understand the impact of CA in a wider context. Regarding the projections of population growth and climate change for SSA, CA is considered as a climate-smart option, i.e. an agriculture able to simultaneously mitigate climate change, adapt to this change, and sustainably increase productivity. The different studies illustrated the capacity of CA to maintain, or even increase production in the long-term, and in the shorter-term under limited or poorly distributed rainfall African contexts. These results suggested an ability of CA to adapt to climate change, predicting an increase in rainfall variability in SSA. However, the climate change mitigation through carbon sequestration under CA remained unclear because of a superficial storage which may be unsteady. Then, we focused on the study area to evaluate the potential of CA to buffer rainfall hazard. Using a 4-year dataset monitoring farmers' fields transitioning to CA, we observed a gradual increase in upland rice average yield with a decrease in variability over the consecutive years of CA practice. The data also suggested a capacity of CA to secure early or late sowing. But agro-environmental factors were mainly impacting yields in the region. This exploratory analysis allowed us to observe positive impacts of CA under the climate conditions of the Lake Alaotra region, suggesting an impact on water balance but no information was available to validate this hypothesis. Finally, we focused more precisely on the impact of mulch on water balance and upland rice yields under the climate conditions of the region, using a modeling approach. We ran an virtual experiment with the model PYE-CA to simulate a range of soil and climate conditions met in the region. We confirmed the ability of mulch to reduce, or even suppress, efficiently surface water runoff. We identified the sowing period within which rice growing would be the least impacted by water stress in the region. The results indicated that water availability for rice cropping was slightly impacted by a decrease in runoff for the majority of soil conditions and farmers' usual sowing dates. Beneficial effects of runoff reduction appeared under higher water stress conditions such as early sowing date or crop intensification and yield variability was decreased. This study allowed us to better apprehend the impacts of CA on water balance in the specific climate context of the study area. It would be interesting to integrate these results at the farm-level to identify the pros and cons of adopting CA under the socio-economic context of the Lake Alaotra region of Madagascar.
106

The Effectiveness of competition law as a merchanism for the protection of the right to food in an African context

Geldenhuys, Megan January 2012 (has links)
This dissertation aims to provide a study on the right to food in an African context and to determine whether or not African states may effectively adopt competition law as a mechanism to protect against hunger. The study begins by examining the right to food and the obligations which flow from this right. Given that the predominant reason that people suffer from hunger is because they lack the ability to economically access adequate food, the dissertation examines the obligations of states to protect this right against abuse from non-state parties. In the framework of the food supply chain, this equates to providing protection against companies such as commodity traders and retailers that have gained a dominant position in the food market and are consequently in a position where they are able to abuse this position of power over the smaller producers and suppliers. The dissertation analyses the importance of the right to food by looking at the key role which smallholder farmers play in their communities. This is central to an African based study because smallholders make up the majority of the world’s hungry people, and it is also the foremost means through which people in Africa gain an income. The study looks at the traditional purpose of competition law and examines whether it would be an effective means to regulate the food market in order to guard against the abusive practices committed by large food companies that threaten the livelihoods of African smallholders. The dissertation concludes with an investigation into the international best practices that can be drawn from competition law regimes across the globe, in order to provide recommendations for a competition regime that is particular to an African context and which would provide the best possible protection for smallholder farmers to ensure that the right to food is upheld. / Dissertation (LLM)--University of Pretoria, 2012. / gm2014 / Centre for Human Rights / unrestricted
107

Landscape-level assessment of ecological and socioeconomic functions of rainforest transformation systems in Sumatra (Indonesia)

Salecker, Jan 14 February 2020 (has links)
No description available.
108

Importance of utilization of social capital in agro-based poverty reduction strategies in smallholder farming area in North-Eastern Zimbabwe

Mupetetsi, Thomas 25 February 2013 (has links)
PHDRDV / Institute for Rural Development
109

An examination of constraints on fruit production by smallholder farmers in Vhembe District

Rathogwa, Alidzulwi Thameson 12 December 2014 (has links)
MRDV / Institute for Rural Development
110

Stoffwechselmonitoring in kleinen und mittelgroßen Milchrindbetrieben im Emsland

Bothmann, Johanna 14 April 2015 (has links)
Problemstellung: Die frühzeitige Erkennung von Störungen vor ihrer klinischen Manifestation ist das Grundanliegen der Prophylaxe. Da besonders die Krankheiten des Fettmobilisationsyndroms fütterungs- und damit stoffwechselbedingt sind, besitzt deren frühzeitige Feststellung durch Stoffwechselkontrollen im peripartalen Zeitraum herausragende Bedeutung. Ziel dieser Analyse war es, Erfahrungen für Indikationen, Durchführung und Ergebnisse mehrjähriger Stoffwechselkontrollen in kleinen und mittelgroßen Betrieben auszuwerten und zu dokumentieren. Dazu wurden die von einer tierärztlichen Gemeinschaftspraxis im Emsland betreuten Betriebe anamnestisch charakterisiert, die Indikationen für Untersuchungen, die Kontrollzeiträume in Laktations- und Jahreszeitverlauf sowie in der jährlichen Abfolge erfasst, die Art und Häufigkeit der untersuchten Parameter sowie ihre klinische Bedeutung insgesamt, betriebsweise sowie z.T. für einzelne Kühe bei Mehrfachkontrollen analysiert. Erfasst wurden auch die von den Landwirten eingeleiteten Maßnahmen sowie die Ergebnisse bezüglich des Gesundheitszustands der Kühe. Versuchsanordnung: Die Anamnesen von 53 Betrieben wurden per Fragebögen erhoben. Aus 60 Betrieben flossen 840 Proben aus 122 Einsendungen mit 793 Blutserumproben und 47 Harnproben von Oktober 2006 bis März 2011 in diese Untersuchung ein. Die Kühe wurden nach Laktationsstadium in die Gruppen ante partum (a. p.), 1. Woche (Wo) post partum (p. p.), 2 - 8 Wo p. p, 9 - 14 Wo p. p, mehr als 100 Tage p. p. und Färsen eingeteilt. Die Parameterauswahl trafen die behandelnden Hoftierärzte mit den Landwirten. Untersucht wurden im Blutserum in absteigender Zahl: Freie Fettsäuren (FFS), ß-Hydroxybutyrat (BHB), Se, Harnstoff, Cu, Ca, anorganisches Phosphat (Pi), Bilirubin, CK, Cholesterol, GLDH, GGT, ß-Carotin, Fe, AST, Total-Protein, Albumin, Na, K, Cl, Mg, Glucose, Gallensäuren, Zn, AP, Kreatinin, Mn, Coeruloplasmin sowie die Trolox Äquivalente Antioxidative Kapazität (TEAC). Harnparameter sind selten untersucht worden. Die Betriebe sind fast ausschließlich Milcherzeugerbetriebe und hatten zwischen 24 und 270 Kühe überwiegend der Rasse Deutsche Holsteins mit einer mittleren Milchleistung von 8718 kg pro Jahr. Ergebnisse: Die häufigsten Merzungsgründe waren schlechte Fruchtbarkeit, Klauen- und Gliedmaßen- sowie Eutererkrankungen. Die Gründe für die Stoffwechselkontrollen waren die Abfrage des aktuellen Stoffwechselstatus sowie das vermehrte Auftreten von Fruchtbarkeitsproblemen, Festliegern, Ketosen und Euterproblemen. Maßnahmen nach der Stoffwechselauswertung waren überwiegend Futterumstellungen sowie die Substitution von Mineralstoffen. Die Einsendungsschwerpunkte lagen jeweils im ersten Jahresquartal. Die mittlere Probenan-zahl/Einsendung sank im Untersuchungszeitraum von 9,7 auf 5,1 ab. Im Durchschnitt wurden 9,9 Parameter/Einsendung untersucht. Bei annähernd 80 % der Einsendungen gaben 40 % bis 70 % der Parameter einen Hinweis auf eine Gesundheitsgefährdung des Bestandes. Im Laktationsverlauf hatten die FFS a. p. mit 56,7 % die häufigsten Abweichungen. Nach der Kalbung bis 8 Wo p. p. sanken sie auf 36 % bis 38 % und im weiteren Verlauf auf < 11 % ab. Die BHB-Abweichungen waren gegensätzlich und lagen in der gesamten Laktation über 68 %. Die FFS-, BHB- sowie Bilirubin-Medianwerte stiegen in der 1. Wo p. p auf 438 μmol/l, 0,86 mmol/l sowie 4,3 μmol/l und sanken dann kontinuierlich im Laktationsverlauf wieder ab. Die Cholesterol-Medianwerte sanken in der 1. Wo p. p. auf 2,16 mmol/l ab und stiegen im Laktationsverlauf bis auf 3,93 mmol/l an. 40 % bis 50 % der Kühe hatten in der Mittel- und Spätlaktation einen Harnstoffüberschuss. Ca und Pi hatten in der 1. Wo p. p. den typischen Konzentrationsabfall auf 2,27 bzw. 1,88 mmol/l, gefolgt von einem kontinuierlichem Anstieg in der Laktation. Hypocalzämien traten zu 13,2 % in der 1. Wo p. p. auf, Hyperphosphatämien überwiegen a. p. mit 24,9 % und in der 1. Wo p. p. mit 22,4 %. Die CK-Mediane betrugen in der 1. Wo p. p. 175,6 U/l; a.p. sowie ab 1. Wo p. p. waren sie > 100 U/I. Ähnlich verhielten sich die CK-Abweichungen mit 60,4 % a. p. und 73,6 % bis 90,9 % ab der 2. Wo p. p. Die CK-Aktivitäten der Färsen sind zu 100 % > 100 U/I. Cu-Mangelzustände wurden bei 12,5 % a. p. und 14,8 % der Kühe in der Spätlaktation beobachtet. Färsen zeigten mit 21,3 % am häufigsten Cu-Unterversorgungen. A. p. bestand zu 20,6 % Se-Unterversorgungen, p. p. hingegen zu 30,1 bis 37% eine Se-Überversorgung. ß-Carotin-Mangelzustände betrugen a. p. 50 % und p. p. 47,1 – 77,8 %. Die TEAC zeigte bei keinen Kontrollen einen Antioxidantienmangel an. Bei den meisten Parametern waren z.T. signifikante Unterschiede zwischen den einzelnen Untersuchungsjahren festzustellen. Bei den FFS und ß-Carotin bestand ein ansteigender Trend an Abweichungen, ein sinkender Trend bei Pi- Abweichungen. In den sechs Kontrolljahren konnte bei 80 % der Betriebe eine Verbesserung der Stoffwechselsituation dokumentiert werden. Bei den Parametern Ca, Pi, Harnstoff, Cholesterol, BHB, Bilirubin, CK und Cu stieg die Zahl physiologischer Werte im Einsendungsverlauf an; nur bei FFS und Se war eine Abnahme zu verzeichnen. Schlussfolgerungen: In kleinen und mittelgroßen Betrieben lieferten systematische Stoffwechselanalysen im peripartalen Zeitraum frühzeitig kausale Hinweise für die häufigsten Krankheiten und Merzungsursachen. Als informative Parameter bewährten sich Indikatoren des Energiestoffwechsels FSS, BHB und Bilirubin, weiterhin Harnstoff, das Se sowie das ß-Carotin. Die systematischen Analysen trugen im Analysenzeitraum zu Verbesserungen in den Betrieben bei. In kleineren Betrieben haben peripartale Einzeltieranalysen besonderen Informationswert über den Herdenzustand.

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