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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.
201

Obraz českých ekofarem po roce 89. Motivace českých farmářů k nekonvenčnímu zemědělství / Reflection of Czech Ecofarms after 1989. Motivation of Czech Farmers to unconventional agriculture

Vocílková, Lenka January 2014 (has links)
This diploma thesis provides a detailed picture of the six Czech organic farms - six Czech organic farmers, who work in different locations in the Czech Republic. It focuses on the motivation for nonconventional methods of agriculture, tells the story of their business, explores and compares the different aspects that may play an important role in bringing holistic picture of Czech organic farming after 1989. Keywords Organic farming, biodynamic agriculture, organic farm, organic farmer, motivation
202

Landwirtschaft in Sachsen hat Zukunft: Diversifizierung, Ökologischer Landbau und Gemeinwohlmarkt

January 2012 (has links)
Die vorliegende Broschüre gehört zu einer Trilogie im Rahmen des Dialogprozesses »Landwirtschaft in Sachsen hat Zukunft«, der im Jahr 2007 von Akteuren aus den verschiedensten Bereichen der sächsischen Landwirtschaft mit Vertretern der Forschung und der Verwaltung ins Leben gerufen wurde. Ziel war es, Strategien zu finden, wie sich Unternehmen der Branche an absehbare Veränderungen von natürlichen, wirtschaftlichen und gesellschaftlichen Rahmenbedingungen anpassen können. In acht Fachforen erfolgte über eine Analyse von bestehenden Rahmenbedingungen die Ableitung von Handlungserfordernissen für den einzelnen Betrieb, aber auch für Politik und branchenübergreifend den gesamten Sektor. Verschiedene Lösungsmöglichkeiten wurden im Rahmen von Projekten gesucht. Die Ergebnisse der Arbeit bis 2012 werden in den drei Broschüren vorgestellt.
203

Seeds of sustainability? : A case study on agricultural sustainability perceptions among small-scale farmers in the Manyara region, Tanzania / Uppfattningar om hållbart jordbruk : En fallstudie av småskaliga jordbrukare i Manyara-regionen, Tanzania

Tarvainen, Evelina January 2020 (has links)
Agricultural policies worldwide are giving an increased focus to the goal of sustainable agriculture, but there are still uncertainties around how this is performed and achieved. As small-scale farmers are a fundamental part of agricultural production worldwide, earlier scholars request deeper understanding of how these farmers perceive sustainable agriculture and how they perceive the pathway towards sustainability. In Tanzania, many small-scale farmers choose to participate in initiatives and organizations under the Organic Farming Movement. By focusing on small-scale farmers that have joined an organic initiative in the Manyara region in Tanzania, this study aims to interpret how these farmers perceive that joining the Organic initiative of a local seed trading system could contribute to sustainable agriculture for them. The study's theoretical approach was a framework where agricultural sustainability consists of an ecological, economic, and social dimension and that normative assumptions of sustainability can be divided into either an Environmentalist or Ecologist approach. Through an open-ended question survey, ten local farmers' perceptions of agricultural sustainability were collected. The result indicates that the farmers perceive that the local seed trading system to some extent will contribute to parts of all three dimensions of agricultural sustainability, and that normative assumptions in both Environmentalism and Ecologism can be identified within the farmer's answers.
204

Durabilité des exploitations en agriculture biologique : une analyse de la diversité des situations et des trajectoires d'évolution en Midi-Pyrénées / Sustainability in organic farms : analysis of diversity of situations and trajectories in the French Midi Pyrenees

Favreau, Jean-Luc 13 December 2013 (has links)
L'agriculture biologique connaît un essor important en France, comme dans la plupart des pays européens. De profondes mutations traversent ce secteur, et de nouveaux modèles de production et de développement apparaissent. Cette thèse se propose d'analyser ces transformations au niveau de l'exploitation agricole, dans le cadre des sciences de gestion, par le biais de la notion de durabilité (en référence à celle de développement durable). L'étude porte sur un échantillon de 74 exploitations de la région Midi-Pyrénées représentant différentes productions. Une première approche apprécie la durabilité de façon synchronique à l'aide d'indicateurs quantitatifs, pour les dimensions agro-écologique, économique et socio-territoriale. Elle fait état de la diversité des formes de durabilité, en lien principalement avec les logiques de fonctionnement des exploitations. Une deuxième approche aborde la durabilité en tant que processus de changement, d'adaptation et d'innovation, par une étude qualitative des trajectoires d'exploitations et des modes de pilotage. Ces études de cas montrent la diversité des trajectoires d'évolution de la durabilité. En dernier lieu, l'analyse met l'accent sur la dimension émergente et incrémentale des dynamiques collectives d'amélioration de la durabilité. / Organic farming is developing strongly in France as in most European countries. The sector is facing fundamental changes, and new production and development models are appearing. This thesis proposes to analyse these transformations at the farm level, from a management perspective, via the concept of sustainability. The study concerns a sample of 74 farms in the French Midi-Pyrénées representing different types of agricultural activity. Sustainability is initially assessed synchronically using quantitative indicators, recording the different forms relating especially to the rationale behind the way farms operate. A second approach looks at sustainability as a capacity for change, adaptation and innovation, via a qualitative study of farm trajectories and management practices. These case studies demonstrate the diversity of pathways leading to the development of sustainability. Finally, the analysis stresses the group dynamics behind improving sustainability, and on the emergent and incremental nature of these developments.
205

Economics of introducing forage and livestock into alternative crop rotation systems during the transition to organic agriculture

Riofrío Ordóñez, Carlos Andrés. January 2006 (has links)
No description available.
206

We Are Earth

Timmerman, Kelsey Wilt 19 July 2022 (has links)
No description available.
207

[pt] COMPOSTAGEM DE RESÍDUOS VEGETAIS EM ÁREA VERDE URBANA: UM EXPERIMENTO NO CAMPUS DA PUC-RIO / [en] COMPOSTING OF PLANT RESIDUES IN AN URBAN GREEN AREA: AN EXPERIMENT ON THE CAMPUS OF PUC-RIO

MARIA CECILIA VERTULLI CARNEIRO 11 October 2021 (has links)
[pt] A compostagem apresenta-se como um dos principais tratamentos e destino para os resíduos orgânicos, entretanto na área urbana tem sido utilizada em pequena escala, pois grande parte desta fração é disposta diretamente em aterros sanitários. Associada à grande oferta de matéria orgânica e a fim de incentivar a adoção desta prática nas cidades, torna-se interessante aliá-la às hortas urbanas, visto que o produto gerado no processo auxilia na fertilidade e fornece nutrientes ao solo. Este trabalho pretendeu testar diferentes misturas de resíduos vegetais em um processo de compostagem em leiras estáticas com aeração passiva realizado dentro de um ambiente urbano com intuito de avaliar os compostos produzidos. A pesquisa se deu por meio de experimento de campo, o qual foi conduzido no campus da PUC-Rio, na cidade do Rio de Janeiro, entre novembro de 2018 e março de 2019. O experimento foi constituído por leiras com 3 diferentes composições e 2 repetições. As misturas foram folha + grama, folha + grama + galho e folha + galho. As matérias-primas foram pesadas no início e no fim do processo. Os compostos produzidos foram pesados e amostras foram levadas para análise em laboratório. A mistura folha + grama foi a mais produtiva; a mistura folha + grama + galho apresentou, em geral, os resultados analíticos mais altos, porém não houve grandes diferenças entre as misturas. Todos os compostos apresentaram resultados satisfatórios e de acordo com padrões existentes em literatura e legislação brasileira relacionada. A metodologia se mostrou eficiente. / [en] Solid waste is a problem, some consequences and negative environmental impacts of its generation and wrong disposal are inappropriate treatment; waste dumps disposal; emissions; air, soil and water pollution; a threat to marine biodiversity; incorporated hazardous substances. In Brazil in 2017, circa 42,3 million tons of MSW collected, equivalent of 59,1 percent, was disposed in sanitary landfill. The rest, 40,9 percent, more than 29 million tons, was disposed in inappropriate places, such as waste dumps and controlled landfills (ABRELPE, 2018). In the country, more than the half of the MSW, 51,4 percent, consists in organic matter (Brasil, 2012). This material is often disposed together with other types of waste. It influences the production of methane from landfills and reduces its lifespan. A very good management, separate collection systems, searching alternatives to give this material a better destination and treatment is necessary. An alternative of treatment to organic waste is composting, a simple and good technology. It is a biological process that occurs mainly by microorganisms action, decomposition of organic matter, such as food scraps, fruits, leaves and manure. The product of the process is the compost, a stable material that is dark brown or black and has an earthy smell, rich in nutrients, able to improve physical, chemical and biological qualities of the soil and may be used in agriculture (Souza et al., 2001; Nunes, 2009). Composting is a useful technique for organic waste management in urban and industrial areas, agricultural use and sustainable development, a satisfactory process for waste treatment (Oliveira et al., 2008; Inácio and Miller, 2009). The high generation of organic waste shows the potential of material able to be treated. According to Leal (2014), the use of these materials is fundamental to cause sustainability of national agriculture and environmental conservation. Thus, avoiding materials from accumulating in a certain location, which can cause environmental problems, taking them to other places for agricultural and plant production. There is in Brazil a specific law for solid waste, it is the law number 12.305 of 2010, that institutes the National Policy on Solid Waste (Política Nacional de Resíduos Sólidos – PNRS, in Portuguese). It defines terms and sets goals. The law mentions composting as a final environmentally adequate destination and that it should be implemented a composting system for organic waste (Brasil, 2010).
208

Carbon and nitrogen distribution and processes in forest and agricultural ecosystems: a study involving solid- and liquid-state NMR and pyrolysis GC/MS

Dria, Karl Jay 17 June 2004 (has links)
No description available.
209

Etre agriculteur bio: engagements individuels, engagements collectifs / Being organic farmer: individual and collective commitments

Vankeerberghen, Audrey 09 July 2011 (has links)
Cette thèse se propose d'explorer ce que signifie "être agriculteur bio" aujourd'hui en Wallonie. Après une analyse socio-historique du développement de l'agriculture biologique dans cette région d'Europe, la première partie s'attache à comprendre en finesse les parcours de vie des agriculteurs bio wallons, leurs pratiques ainsi que la construction de leurs identités professionnelles. La deuxième partie se penche quant à elle sur les aspects institutionnels de l'agriculture bio :sur la structuration du secteur syndical et associatif ainsi que sur les interactions entre les pratiques des agriculteurs et la législation encadrant l'agriculture biologique. / Doctorat en Sciences politiques et sociales / info:eu-repo/semantics/nonPublished
210

The influence of different management practices on soil faunal activity in vineyard soils

Albertus, Randal Marius Colin 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Food demands for the ever-increasing human population is increasing the pressure on the agricultural sector to produce more food. In order to satisfy these demands, farmers are turning to chemical biocides for the control of pest species to produce greater crop yields. All pesticides must be toxic or poisonous to the target species they intend to control. Unfortunately, most pesticides are toxic or poisonous to non-target organisms as well, with detrimental effects on their health. Organic farming was developed to enhance the overall health of the farm's natural soilmicrobe- plant-animal biodiversity. No synthetic fertilisers and/or pesticides are used when farming organically. Life in the soil consists of intricate food webs and interactions between the soil dwelling invertebrates. The soil-organisms are divided into three main groups, viz., Micro-organisms (e.g. protozoa, bacteria and fungi) mesofauna (nematodes, Collembola and Acari) and macro-fauna (e.g. millipedes, isopods, insects, molluscs and earthworms). The invertebrates are very susceptible to chemical contamination by chemical biocides in natural and agro-ecosystems. The soil invertebrate communities are responsible for the decomposition of organic material in soil, thereby remineralising the soil. The decomposition processes start with comminution of the large pieces of organic material by meso- and macro-fauna and ends with the micro-fauna and microbial organisms that complete these processes by returning the nutrients in an inorganic form to the soil. The aim of this study was to investigate whether, and to what extent the soil organisms are influenced by different management practices viz., organic management practices versus conventional management practices. A vineyard on the farm Plaisir de Merle, in Simondium, Western Cape was used for the present study. One half of a one hectare vineyard was managed organically and the other half conventionally. Within each vineyard block six different treatments were performed. Three of the treatments were strictly organic and the other three were strictly conventional. Four replicates of each management treatment were performed. The bait-lamina technique was used to assess the feeding activity of the soil organisms exposed to the different management treatments. In addition to the bait-lamina trials in the vineyard itself, bait-lamina tests were performed in microcosm studies with soil from the organically and conventionally managed vineyard blocks under controlled conditions. In order to assess the impact of the various pesticides that are used in the vineyards in the conventional way, on the soil fauna, standard acute toxicity tests and behavioural tests were performed on Eisenia fetida, the compost worm. The bait-lamina tests in the vineyard revealed that the moisture content of the soil plays an important role in the biological activity of soil fauna. The different management treatments did affect the biological activity of the soil fauna, but seasonal changes also proved to be one of the important factors governing biological processes in the soil. The acute toxicity tests showed that the active ingredients (mancozeb, penconazole and trifloxystrobin) of three of the pesticides that were tested in this study, had negatively affected E. fetida at their recommended application concentrations. The remaining two pesticides' active ingredients (glyphosate and N-acetyl salicylic acid) did not affect the earthworms negatively at the recommended application concentrations. The preference behavioural trials showed that E. fetida could detect and avoid contaminated substrates at the LCso-concentrations of the different pesticides. All the earthworms were influenced positively in the preference behaviour experiments. Because of certain limitations of the bait-lamina technique, it was difficult to formulate conclusions on what happens in the soil. A possible explanation for the differences in feeding activity of soil fauna could be attributed to the migration of the soil fauna to more habitable soil horizons during the dry summer conditions, when most of the pesticides are applied. The ecological relevance of the acute toxicity tests conducted need to be investigated further. It is clear that the acute toxicity tests provided important information that should be considered, but care should be taken and the necessary safety factors be determined and considered when doing risk assessment studies. The results of the preference behaviour studies showed that for certain pesticides E. fetida can be a sensitive bioindicator of acute and/or sub-acute lethal toxicity testing but this might not necessarily be the case for other pesticides. The goal of doing laboratory studies is to gain as much information to make reliable extrapolations to field situations from laboratory data. Laboratory-to-field extrapolations are very complicated because of the physico-chemical composition of soil, the unpredictable way pesticides behave within soil and the reaction of soil organisms to the soil and to the chemical biocides that are used. Further studies need to be done in order to fully understand to what extent the soil fauna were affected by the different management practices applied to the vineyard at Plaisir de Merle. / AFRIKAANSE OPSOMMING: Voedsel aanvraag vir die toenemende menslike bevolking plaas groot druk op die landbou sektor om meer kos te produseer. Om aan die voedsel eise te voldoen, gebruik boere al meer chemiese biosiede om pesspesies te bestry. Alle pestisiede moet toksies of giftig wees vir die teiken organisme waarvoor dit bestem is. Ongelukkig is die meeste pestisiede ook toksies of giftig vir nie-teiken organismes, wat tot nadelige effekte op hul gesonheid kan lei. Organiese boerdery is ontwikkel om die algehele gesondheid van die plaas se natuurlike grond-mikrobe-plant-dier biodiversiteit te bevorder. Geen sintetiese bemestingstowwe en/of pestisiede mag gebruik word wanneer daar organies geboer word nie. Die lewe in die grond bestaan uit ingewikkelde voedselwebbe en interaksies tussen die grondlewende invertebrate. Die grond invertebrate word verdeel in drie hoof groepe, nl. mikro-organismes (bv. Protozoa, bakterieë en fungi) meso fauna (Nematoda, Collembole en Acari) en makrofauna (bv. Millipoda, Isopoda, Insecta, Mollusca en erdwurms). Die Invertebrata is die mees vatbaarste vir chemiese kontaminasie deur chemiese biosiedes in natuurlike en landbou ekosisteme. Die grond invertebraat gemeenskappe is verantwoordelik vir die afbreek van alle organiese materiaal in die grond en dus vir remineralisering van die grond. Die afbreekproses begin by die komminusie van groter stukke organiese materiaal deur die meso- en makrofauna en eindig met die mikrofauna en mikrobes wat die prosesse voltooi deur die nutriente terug te plaas in die vorm van anorganiese produkte in die grond. Die doel van hierdie studie was om te ondersoek of, en tot watter mate, grond organismes geraak word deur verskillende grondbestuurspraktyke, nl. Organiese grondbestuurspraktyke teenoor die konvensionele grondbestuurspraktyke. 'n Wingerd op die plaas Plaisir de Merle, in Simondium, Wes-Kaap, was gebruik vir die huidige studie. Een helfte van 'n een hektaar wingerd is organies bestuur en die ander helfte is op die konvensionele manier bestuur. Op elk van die twee wingerd blokke is ses verskillende behandelings toegepas. Drie van die behandelings was streng organies en die ander drie was streng konvensioneel van aard. Vier replikate van elke behandeling is toegepas op elk van die twee wingerdblokke. Die bait-lamina metode is gebruik om die voedingsaktiwiteit van die grond organismes te asses seer. As toevoeging tot die bait-lamina proewe in die wingerd self, is bait-lamina toetse ook in mikro-kosmosse in die laboratorium gedoen met grond afkomstig vanaf die twee wingerdblokke. Om die impak van die verskillende pestisiede op die grondorganismes te ondersoek, is standaard akute toksisteitstoestse en gedragstoetse uitgevoer met die komposerdwurm, Eisenia fetida. Die bait-lamina resultate in die wingerd het getoon dat die voginhoud van die grond die belangrikste rol speel wat die biologiese aktiwiteit van die grondorganismes beïnvloed. Die verskillende behandelings het die biologiese aktiwiteit van die grond fauna geaffekteer, maar seisoenale veranderings is ook uitgesonder as een van die bepalende faktore wat die biologiese prosesse in die grond stuur. Die akute toksisiteitstoetse het getoon dat die aktiewe bestandeie van drie van die pestisiede (mancozeb, penconazole en trifloxystrobin), E. fetida negatief beïnvloed het teen die aanbeveelde konsentrasies wat toegedien is. Die aktiewe bestandeie van die ander twee pestiede (glyphosate en N-asetiel sallisiel suur) het nie die erdwurms nadelig beïnvloed teen die aanbeveelde konsentrasies wat toegedien is nie. Die gedragsproewe het getoon dat E. fetida die LCso-konsentrasies van al die verskillende pestisiede kan waarneem en vermy. Al die erdwurms is positief beïnvloed in die gedragseksperimente met die verskillende pestisiede. Omdat die bait-laminametode sekere beperkings het, was dit moeilik om tot gevolgtrekkings te kom oor wat presies in die grond gebeur. 'n Moontlike verklaring vir die verskillende voedingsaktiwiteite van die grond fauna kan toegereken word aan die migrasie van die grondorganismes na meer leefbare grondhorisonne gedurende die droë somer toestande, wat toevallig met die spuit van die meeste pestisiede ooreenstem. Die ekologiese relevansie van die akute toksisiteitstoetse wat uitgevoer is, moet meer deeglik ondersoek word. Die belangrikheid van die akute toksisteitstoetse is duidelik en het waardevolle informasie gelewer, maar sorg moet geneem word, en die nodige veiligheids faktore moet bepaal word en in ag geneem word, wanneer riskobepalingstudies gedoen word. Die gedragsproewe het getoon dat vir sekere pestisiede E. fetida 'n sensitiewe bioindikator van akute en/of sub-akute letale toksisiteits toetse kan wees, maar nie noodwendig vir ander pestisiede nie. Die doel van laboratoriumstudies is om so veel as moontlik inligting te versamelom vertroubare ekstrapolasie te kan maak na situasies in die veld vanaf laboratorium data. Laboratorium-na-veld ekstrapolasies is dikwels baie gekompliseerd as gevolg van die fisies-chemiese samestelling van die grond, die onvoorspelbare manier waarop chemiese pestisiede met die grond reageer en die reaksie van die grondorganismes op chemiese biosiede in die grond. Verdere studies moet gedoen word om so deeglik maanlik die mate van die impak wat die verskillende bestuurspraktyke op die grond fauna het, te verstaan op Plaisir de Merle.

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