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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.
1

Farmland heterogeneity effects on biodiversity, community traits and insect pollination

Haß, Annika Louise 15 May 2018 (has links)
No description available.
2

The Economic Value of Crop Diversity in the Czech Republic / The Economic Value of Crop Diversity in the Czech Republic

Tyack, Nicholas January 2016 (has links)
We estimate the willingness-to-pay for conserving crop diversity in the Czech Republic. Discrete choice experiments are used to elicit preferences for the conservation of wine, hop, and fruit tree varieties, while a double-bounded dichotomous choice approach is used to elicit preferences for the conservation of unspecified, "general" crop diversity. The WTP values are derived for both of these contingent products from a sample representative of the general Czech population (n=731) and a sample of respondents living in the South Moravian region that is characterized by agriculture and wine production (n=418). We demonstrate a strong preference for conserving fruit trees over hops and wine varieties, and derive positive mean WTP of the general Czech population (ages 18-69) of 56 Kč ($2.26). Mean WTP for the conservation of general crop diversity is 167 Kč ($6.80). On average, residents of South Moravia have a greater WTP for "general" crop as well as fruit tree conservation. In total, the Czech adult population (ages 18-69) has an aggregate WTP of ~1.25 billion Kč ($50.5 million) for the conservation of general crop diversity, and ~410 million Kč ($16.8 million) for the conservation of fruit trees, revealing the previously unmeasured social welfare benefits of these activities. The estimated benefits...
3

Solutions from Below : A strategic approach for the sustainable management of organised community seed banks / Solutions from Below : A strategic approach for the sustainable management of organised community seed banks

Serrure, Laurent, Rootes, Lucia Beltrame and Zachary January 2013 (has links)
Organised community seed banks (OCBSs) are one of the main tools to preserve crop diversity at a local level and therefore constitute an important driver for local resilience, as well as an important tool to move society towards sustainability. Agriculture is a fundamental leverage point for society: it fulfils a basic survival need as well as being one of the causes of humans’ unsustainable impact on the environment. It also holds the key to the preservation of biodiversity, which is increasingly important in the face of climate change and extreme weather conditions, and the reduction in use of chemical fertilisers and pesticides, which is necessary to move towards sustainability. Organised community seed banks have the potential to be a tool for this preservation of biodiversity, however, there is currently a lack of literature, resources and guidelines to position them as such. This research set out to identify the challenges that OCSBs face that could affect their success in contributing to a sustainable society, and the gaps between what management resources are available to them and their current management practices. With the aid of organised seed bank representatives and experts from around the world, the result was the design of a strategic approach to help OCSBs address their challenges and allow them to better contribute to the provision of food sovereignty, food security and socio-ecological sustainability.
4

Landscape heterogeneity affects arthropod functional diversity and biological pest control

Bosem, Aliette 01 February 2017 (has links)
No description available.
5

« Provincialiser » la Révolution Verte : savoirs, politiques et pratiques de la conservation de la biodiversité cultivée (1943-2015) / “Provincialising” the Green Revolution : knowledges, Policies and Practices in the Conservation of Crop Biodiversity (1943-2015)

Fenzi, Marianna 28 November 2017 (has links)
Le problème de l’accès aux ressources génétiques des plantes pour la sélection variétale est au cœur de la Révolution Verte. A partir des années 1960, les sélectionneurs font de la disparition des variétés locales sous l’effet de la diffusion de nouvelles variétés génétiquement homogènes un problème public à l’échelle mondiale. Dans une perspective qui croise la recherche d’archives et l’enquête de terrain, cette thèse revient sur la formation de ce problème, sur sa trajectoire historique et ses enjeux actuels. Il s’agit d’analyser l’hétérogénéité des savoirs scientifiques et des approches qui sont développés sur le thème de la conservation des ressources génétiques dans les arènes internationales. L’étude des débats et des initiatives menés dans le cadre de la FAO permet de comprendre quels sont les savoirs légitimés, lesquels sont marginalisés et comment la nature et les contours du problème ont été négociés. La place que les ressources génétiques occupent au cours d’épisodes clés de la Révolution Verte est également au cœur de ce travail. Cette thèse analyse spécifiquement l’importance accordée aux variétés locales de maïs dans le programme agricole que la Fondation Rockefeller met en place au Mexique à partir de 1943. Alors que le maïs hybride est généralement présenté comme un vecteur de la modernisation agricole, cette thèse montre que les experts sont confrontés à l’échec du paradigme d’amélioration variétale qu’ils étaient censés exporter. Face à une innovation uniquement applicable à une échelle très limitée, les semences paysannes du maïs restent l’option variétale la plus utilisée au Mexique. Ce travail montre que ce sont bien les choix pragmatiques des agriculteurs qui constituent le fondement de la conservation, de facto, des ressources génétiques du maïs dans ce pays. / The issue of access to plant genetic resources for plant breeding is at the heart of the Green Revolution. Beginning in the 1960s, the disappearance of local varieties with the spread of new genetically homogeneous varieties evolved into a public problem on a global scale. Combining archival research and field investigations, this thesis explores the emergence of this problem, its historical trajectory, and its current forms. I analyze the heterogeneity of scientific knowledge and approaches to the conservation of genetic resources developed in international arenas. An exploration of debates and initiatives within the framework of the FAO sheds light on the issues of which knowledges are legitimated and which marginalized, and on how the nature and outlines of the problem have been negotiated. An examination of the role of genetic resources in key episodes in the Green Revolution is also central to the study. The thesis specifically analyzes the importance attributed to local maize varieties in the agricultural program that the Rockefeller Foundation implemented in Mexico beginning in 1943. While hybrid maize is generally presented as a vector of agricultural modernization, this thesis shows how experts were faced with the failure of the varietal improvement paradigm that they were supposed to export. As hybrid maize is an innovation that is only applicable on a very limited scale, farmers’ maize seeds still are the most widely used varietal option in Mexico. The study shows that it is indeed the pragmatic choices of farmers that form the basis for the de facto conservation of the country’s maize genetic resources.
6

Rural Homegardens in Central Sulawesi, Indonesia: An Example for a Sustainable Agro-Ecosystem? / Ländliche Hausgärten in Zentral-Sulawesi, Indonesien: Ein Beispiel für ein nachhaltiges Agrar-Ökosystem?

Kehlenbeck, Katja 15 May 2007 (has links)
No description available.

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