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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.
121

Agricultural waste and wood waste for pyrolysis and biochar : An assessment for Rwanda​ / Jordbruks- och träavfall för produktion av biokol : En utvärdering för Rwanda​

Eliasson, Jenny, Carlsson, Viktor January 2020 (has links)
A high priority in order to combat climate change is disposal of waste. In low-income countries, a large portion of biomass residues generated in the forestry, agricultural and industrial sectors could be usable, instead of being seen as waste. For instance, it could be converted into biochar, which is proven to have many environmental benefits. In Rwanda, the agricultural sector employs 80% of the population and accounts for 35% of GDP. This sector, together with later refinement of crops and forestry production, cause large amounts of residue that many times is considered as waste. In this report, a literature study was conducted to evaluate possible biochar production from agricultural and wood wastes in Rwanda. Characteristics that determine if a biomass could be suitable for a biochar production were identified as C, H, O, N, S, hemicellulose, cellulose, lignin, ash and moisture content, residue-to-product ratio, and low heating value. These characteristics were assessed for the chosen Rwandan agricultural and wood wastes, by compiling values from published reports. The result shows that there are large volumes of residues that have potential for biochar production instead of being seen as waste in Rwanda. Biochar production from these wastes could enable environmental benefits for Rwanda, although further investigation of each single biomass could be needed in order to see if it is practically, technically and financially possible to do in reality. / För att bekämpa klimatförändringen är avfallshantering en hög prioritet. I låginkomstländer kan en stor andel av biomassarester som genereras i skogsbruk, jordbruks- och industrisektorer vara användbara, istället för att ses som avfall. Till exempel skulle det kunna omvandlas till biokol, som har visats sig ha många miljömässiga fördelar. I Rwanda arbetar 80% av befolkningen inom jordbrukssektorn och den står för 35% av BNP. Denna sektor, tillsammans med förädling av grödor och skogsbruksproduktion, orsakar stora mängder rester som många gånger betraktas som avfall. I denna rapport genomfördes en litteraturstudie för att utvärdera möjlig produktion av biokol från jordbruks- och träavfall i Rwanda. Egenskaper som avgör om en biomassa kan vara lämplig för en biokolsproduktion identifierades som C-, H-, O-, N-, S-, hemicellulosa-, cellulosa-, lignin-, ask- och fukthalt, samt andel avfall som uppstår i förhållande till färdig produkt och värmevärde. Dessa egenskaper utvärderades för det valda jordbruks- och träavfallet genom att sammanställa värden från publicerade rapporter. Resultatet visar att det finns stora volymer rester som har potential för biokolsproduktion istället för att ses som avfall i Rwanda. En biokolsproduktion från dessa avfall skulle kunna ge miljömässiga fördelar för Rwanda, även om ytterligare undersökning av varje enskild biomassa skulle behövas för att se om det är praktiskt, tekniskt och ekonomiskt möjligt att genomföra i verkligheten.
122

Climate change and agricultural production in Limpopo Province : impacts and adaptation options

Maponya, Phokele Isaac 12 1900 (has links)
The primary aim of my research was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: To understand the impacts of climate variability and change on agricultural production in Limpopo province , To assess the impacts of climate variability and change on agricultural production in Limpopo province and To identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16- 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. The Limpopo province is one of the poorest provinces in the country, characterized by high unemployment rate, poverty and lack of access to a range of resources that frustrate majority of people ability to secure their livelihoods. In this study the province's economic, biological and physical environment were highlighted. The study further covers the province, s farming enterprises, systems, categories, infrastructure as well as other constraints that maybe facing the emerging farmer in the province. It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts are using different coping and adaptation strategies in order to increase their crop yields. Literature studies show that climate variability and change adaptation strategies vary from area to area due to agro ecological zones and the harshness of the effects of climate variability and change. It has also been noted that climate change is fast pushing the poorest and most marginalized communities beyond their capacity to respond. This study draws on lessons learned, experiences, and other existing research on climate change impacts and adaptation across the globe. It sets out what is needed to enable people living in poverty to adapt to climate change, and a range of interventions that are available across climate - sensitive sectors. The study has provided a literature review of the impact of climate change on the agricultural sector. In fact, it has documented some of the likely impacts of climate change based on International, continental, regional, national and provincial agricultural sector. The study highlighted the impact of climate change also on various climate - sensitive sectors including understanding water resources, forestry, natural ecosystem human health, infrastructure and coastal zones. This research also confirmed that being a full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. A worrying situation is reviewed globally in this study and it can be concluded that climate variability and change is affecting every sector in society and it needs urgent attention. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends oftemperature and precipitation. The study also presented perceived adaptation strategies used by farmers in Limpopo province. Some of their perceived adaptation strategies included: (a) Soil management strategies, (b) Water management strategies and (c) Others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this study including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this study are potentially valuable to the agricultural sector considering the threats that climate change poses across climate sensitive sectors. / Environmental Sciences / D. Phil. (Environmental Management)
123

La producción y la productividad de los factores en la agricultura española, 1752-1935

Bringas Gutiérrez, Miguel Angel 13 November 1998 (has links)
En esta tesis se estudia la producción agrícola y la productividad de los factores en la agricultura española (tierra, trabajo y simiente) desde 1752 hasta 1935. La tendencia a largo plazo de la producción agrícola se analiza desde una estimación directa (datos sobre cantidades), otra estimación indirecta (a través de los datos sobre precios). La productividad de los factores se estudia desde una doble perspectiva: la productividad simple de los factores y la productividad total de los factores. Para analizar la productividad simple de los principales factores de la agricultura se ha recurrido tanto a examinar la productividad media (vía de las cantidades) como la productividad marginal (vía de los precios, es decir, renta de la tierra y salarios agrícolas).Además de la utilización de nuevas fuentes en esta investigación (Cuadernos generales de la Riqueza, boletines oficíales provinciales, cartillas evaluatorias, etc.) y de la aplicación de la teoría económica para deducir cantidades a partir de la información disponible sobre precios, las principales conclusiones que se han alcanzado en esta tesis se centran en la constatación de un importante crecimiento de la producción agrícola (a una tasa anual acumulada entre 0,8 y el 1,5 por 100 desde 1799/1800 hasta 1900/05) y en el incremento de la productividad de la tierra, de la simiente y de la productividad total de los factores antes de finalizar el siglo XIX. / This thesis studies agricultural production and the productivity of factors for Spanish agriculture (land labour, and seed) from 1752 to 1935. The long-run trend of agricultural production is approached from direct estimates (information on quantities) and indirect estimates (information on prices). The productivity of factors is considered from a twofold viewpoint: the single productivity of factors and the total productivity of factors. In order to analyse the single productivity of the main agricultural factors, the thesis examines average productivity (quantities method) as well as marginal productivity (prices method), i.e. land rent and agricultural wages. To this goal, this research has extensively used new sources (Cuadernos de Riqueza, Boletines Oficiales Provinciales, cartillas evaluatorias) and has applied economic theory to deduce quantities from the available historical information on prices. The main conclusions obtained by this thesis deal with the existence of an important growth of agricultural production (annual rates accumulate between 0.8 and 1.5 per cent from 1799/1800 to 1900/1905) and an increase in land productivity, seed productivity and total factor productivity in Spain well before the end of the nineteenth century.
124

Roots of History, Seeds of Change: Women Organic Farmers & Environmental Health in Jamaica

Harris, Laila Zahra 11 September 2012 (has links)
This research seeks to address the gap in the literature on women, health, and environments by exploring the factors that motivate Jamaican women farmers to practice organic agriculture and how these might relate to their understandings of environment and health. The experiences and decisions of women farmers are also positioned within wider historical contexts of colonialism and agricultural change. Integrating a variety of theoretical frameworks, including public issues anthropology, ethnoecology, rural sociology, and feminist political ecology, my own scholarly analysis is merged with the perspectives of the women farmers interviewed in this qualitative study. This research found that women organic farmers in Jamaica were motivated by various factors related to environment and health and impacted by the island’s legacy of slavery and industrialization. The findings of this thesis can be used to encourage the practice of organic agriculture and to improve human health and environmental wellbeing in Jamaica and beyond. / Richard and Sophia Hungerford Travel Scholarship, Yeandle Family Graduate Scholarship, Richard and Sophia Hungerford Graduate Scholarship, Registrar’s Research Grant for Graduate Students, Registrar’s Research Travel Grant
125

The Nexus between Agricultural Productivity, Poverty, and Social Services Provision in Sub-Saharan Africa: An Empirical Analysis

Reimers, Malte 21 November 2014 (has links)
No description available.
126

The impact of climate change on agricultural crop production in the Vhembe District Municipality, Limpopo Province South Africa

Musetha, Mboniseni Aubrey 09 1900 (has links)
The aim of this research was to identify the impacts and adaptation options of climate variability and change on agricultural crop production in Vhembe District Municipality. The study will contribute to the expansion of existing literature on climate change impacts on agricultural sector. The following two main objectives were formulated for the purpose of this study:  To determine the level of awareness of small-scale maize farmers about climate change impacts and threats in Vhembe District Municipality (VDM),  To compare the level of production scales between the farmers who are aware and the farmers who are not aware of climate change impacts and its threats. The study area was the Vhembe District Municipality; a representative sample of 150 farmers (aged 18 – 65+ years, 46 percent males and 54 percent females) participated in the study. Vhembe District Municipality is one of poorest municipalities in Limpopo due to lack of infrastructure development, and as a result of that, there is an increase of socio-economic problems such as food prices increase, unemployment, scarcity of food, and lack of local markets. The study further covers the municipality’s farming enterprises, systems, categories, infrastructure as well as other constraints that may be facing the emerging farmer in the District. The study highlighted the lack of climate change information, reduction of livestock production and crop yields of the farmers in the Vhembe District. The literature studies show climate variability and change adaptation strategies such as planting different varieties, crop diversification, different planting dates and shortening of growing periods. This study draws on lessons learned, experiences, and other existing research on climate change impact and adaptation across the globe. It was concluded during the research that change in climate was already perceived by farmers in the Vhembe District and the study also presented perceived adaptation strategies used by farmers in the Vhembe District. The study concludes that there is lack of local market, and low level of farmers’ awareness about the impact of climate change on the crop production in the Vhembe district. This low level of awareness translates into a low level of crop production which results in increased socio-economic problems, low income, increased unemployment, increased crops diseases and reduced crop yields. / Environmental Sciences / M. Sc. (Environmental Management)
127

Climate change and agricultural production in Limpopo Province : impacts and adaptation options

Maponya, Phokele Isaac 12 1900 (has links)
The primary aim of my research was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: To understand the impacts of climate variability and change on agricultural production in Limpopo province , To assess the impacts of climate variability and change on agricultural production in Limpopo province and To identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16- 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. The Limpopo province is one of the poorest provinces in the country, characterized by high unemployment rate, poverty and lack of access to a range of resources that frustrate majority of people ability to secure their livelihoods. In this study the province's economic, biological and physical environment were highlighted. The study further covers the province, s farming enterprises, systems, categories, infrastructure as well as other constraints that maybe facing the emerging farmer in the province. It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts are using different coping and adaptation strategies in order to increase their crop yields. Literature studies show that climate variability and change adaptation strategies vary from area to area due to agro ecological zones and the harshness of the effects of climate variability and change. It has also been noted that climate change is fast pushing the poorest and most marginalized communities beyond their capacity to respond. This study draws on lessons learned, experiences, and other existing research on climate change impacts and adaptation across the globe. It sets out what is needed to enable people living in poverty to adapt to climate change, and a range of interventions that are available across climate - sensitive sectors. The study has provided a literature review of the impact of climate change on the agricultural sector. In fact, it has documented some of the likely impacts of climate change based on International, continental, regional, national and provincial agricultural sector. The study highlighted the impact of climate change also on various climate - sensitive sectors including understanding water resources, forestry, natural ecosystem human health, infrastructure and coastal zones. This research also confirmed that being a full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. A worrying situation is reviewed globally in this study and it can be concluded that climate variability and change is affecting every sector in society and it needs urgent attention. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends oftemperature and precipitation. The study also presented perceived adaptation strategies used by farmers in Limpopo province. Some of their perceived adaptation strategies included: (a) Soil management strategies, (b) Water management strategies and (c) Others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this study including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this study are potentially valuable to the agricultural sector considering the threats that climate change poses across climate sensitive sectors. / Environmental Sciences / D. Phil. (Environmental Management)
128

Farmářské trhy jako návrat k tradici / Farmer's marketplaces as a restoration of tradition

ANDRLOVÁ, Lucie January 2013 (has links)
The theoretical part of this thesis defines the terms distribution and marketplaces. It is also concerned with the agricultural production of the Czech Republic and the quality of products on the Czech market. In the closing part there is a detailed description of farmer's marketplaces in the Czech Republic from 2009 until now and also the problematic aspects related to this kind of sale and its grant support. The practical part is based on intended aims, hypothesis and used methodology, and describes the course of farmer's marketplaces in two surveyed locations (South Bohemia and Prague) on various levels. It deals with an inspection of these farmer's marketplaces by the surveillance authorities of the Czech Republic, a complete analysis of these marketplaces, and a comparison of chosen marketplaces which were visited by the author of this work. Next is an evaluation of a questionnaire survey upon which the consumers' stance to this type of sale is being based. This includes people who do shop at these marketplaces as well as people who do not. In the end of the practical part all gained data are gathered, possible improvements are suggested, and the possible future development of this type of sale is proposed.
129

A Bioeconomic Model of Indoor Pacific Whiteleg Shrimp (<i>Litopenaeus Vannamei</i>) Farms With Low-Cost Salt Mixtures

Patrick N Maier (8800949) 08 May 2020 (has links)
Using a bioeconomic model and stochastic simulation to assess the economic viability of small-scale, recirculating shrimp farms in the Midwestern U.S. A series of stress tests were implemented on key input variables including survival rate, selling price, electricity usage, discount rate and the cost of added salt. The key output variable is the Net Present Value of the operation. <div><br></div><div><br></div>
130

Sicurezza alimentare nei Paesi in Via di Sviluppo: il caso studio del progetto “Produzione di cibo appropriato; sufficiente, sicuro e sostenibile" / FOOD SECURITY IN DEVELOPING COUNTRIES: THE CASE OF "PRODUCTION OF APPROPRIATE FOOD: SUFFICIENT, SAFE AND SUSTAINABLE" PROJECT

MINARDI, ANDREA 16 December 2019 (has links)
L’insicurezza alimentare colpisce soprattutto le famiglie rurali povere che vivono di agricoltura di sussistenza nei Paesi in via di Sviluppo. Nell’ottica di fornire un supporto alle comunità che si trovano in queste condizioni, L’Università Cattolica del Sacro Cuore e la Fondazione Romeo ed Enrica Invernizzi hanno avviato nel 2012 il progetto “Produzione di cibo appropriato, sufficiente, sicuro e sostenibile”. Il progetto si propone di avviare Centri Pilota in collaborazione con le diocesi che promuovano uno una intensificazione delle produzioni agricole e una dieta sostenibile dal punto di vista etico-sociale, economico e ambientale. I Paesi in cui opera il progetto sono l’India (Meghalaya State) e la Repubblica Democratica del Congo – RDC (Lomami province). Con l’aiuto dei team locali sono state raccolte informazioni sulle abitudini produttive e alimentari della popolazione. Su questi dati è stata svolta una analisi circa l’impatto che il progetto ha avuto sulla sicurezza alimentare (disponibilità e accesso) delle famiglie coinvolte. Il numero di polli allevati (India) e l’Household Dietary Diversity Score (India and RDC) sono stati utilizzati come proxy per la disponibilità e l’accesso di cibo, rispettivamente. L’analisi statistica è stata effettuata usando differenti approcci dello Propensity Score Match (Logit + Nearest Neighbour and GenMatch) per valutare ATT (Effetto medio del trattamento sul gruppo “trattato”). Per quanto riguarda l’India sono stati analizzati i) il numero di polli allevati (food availability) e ii) l’HDDS (Household Dietary Diversity) per la food access. Il progetto ha avuto un impatto positivo ma non significativo sul numero di polli allevato, che però non si è tradotto in un miglioramento dell’HDDS delle famiglie di piccoli agricoltori coinvolti nel progetto. Per la RDC è stato analizzato solo l’impatto sulla food access (HDDS). In questo caso l’impatto del progetto sulla sicurezza alimentare dei piccoli agricoltori è stato positivo ma non significativo. I risultati mostrano che un miglioramento nella qualità della dieta (HDDS) implica, oltre ad un miglioramento delle produzioni (in qualità e in quantità), è necessario anche un miglioramento della educazione (anche nutrizionale) e dell’accesso al mercato. / Food Insecurity (FI) affects especially poor rural people that rely on Subsistence Agriculture in developing countries. With the purpose to help the community that living in that conditions, in 2012 the Università Cattolica del Sacro Cuore and the Fondazione Romeo ed Enrica Invernizzi have started the “Production of appropriate food: safe sufficient and sustainable” project. The project aims to open Pilot Center in agreement with local Diocese to promote the Agricultural production Intensification agriculture and Diets that are sustainable (ethical, economic and environmental). The project is active in India (Meghalaya State) and the Democratic Republic of Congo (Lomami Province). Helped by the local team, information was collected on production and diets habits. An analysis of the impact that the project had on food security (availability and access) of the families involved was carried out on these data. Number of Chicken (India) and Household Dietary Diversity Score - HDDS (India and DRC) as a proxy for food availability and access, were respectively utilised. Thus, we used different Propensity Score Match approach (Logit + Nearest Neighbour and GenMatch) to evaluate the ATT (average treatment effect on the treated group). Regarding India, the number of chickens bred (as food availability) and the HDDS (food access) were analyzed. While the number of chickens bred is positive but not significant, the HDDS values of smallholder farmers involved in the project did not improved. Moving to DRC, only the HDDS was analyzed. In this case, the project had a positive impact on beneficiary families, but it was not significant. The results point out that diet improving (HDDS) advances the production, both in quality and quantity, but is not a sufficient condition per se. Furthermore, it is also essential to enhance the educational path which focuses on nutritional issues and the access to food from market.

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