Tesi: "Organic and conventional farming practices"

1

Kinney, Erinna Lea. "Isolation, identification, and antimicrobial susceptibility analysis of (Enterococccus) spp. and (Salmonella) spp. from conventional poultry farms transitioning to organic farming practices". College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9315.

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Thesis (M.P.H.) -- University of Maryland, College Park, 2009.
Thesis research directed by: Dept. of Public and Community Health. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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2

Stark, Christine. "Effects of long- and short-term crop management on soil biological properties and nitrogen dynamics". Phd thesis, Lincoln University. Agriculture and Life Sciences Division, 2005. http://theses.lincoln.ac.nz/public/adt-NZLIU20070220.010748/.

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To date, there has been little research into the role of microbial community structure in the functioning of the soil ecosystem and on the links between microbial biomass size, microbial activity and key soil processes that drive nutrient availability. The maintenance of structural and functional diversity of the soil microbial community is essential to ensure the sustainability of agricultural production systems. Soils of the same type with similar fertility that had been under long-term organic and conventional crop management in Canterbury, New Zealand, were selected to investigate relationships between microbial community composition, function and potential environmental impacts. The effects of different fertilisation strategies on soil biology and nitrogen (N) dynamics were investigated under field (farm site comparison), semi-controlled (lysimeter study) and controlled (incubation experiments) conditions by determining soil microbial biomass carbon (C) and N, enzyme activities (dehydrogenase, arginine deaminase, fluorescein diacetate hydrolysis), microbial community structure (denaturing gradient gel electrophoresis following PCR amplification of 16S and 18S rDNA fragments using selected primer sets) and N dynamics (mineralisation and leaching). The farm site comparison revealed distinct differences between the soils in microbial community structure, microbial biomass C (conventional > organic) and arginine deaminase activity (organic > conventional). In the lysimeter study, the soils were subjected to the same crop rotation (barley (Hordeum vulgare L.), maize (Zea mays L.), rape (Brassica napus L. ssp. oleifera (Moench)) plus a lupin green manure (Lupinus angustifolius L.) and two fertiliser regimes (following common organic and conventional practice). Soil biological properties, microbial community structure and mineral N leaching losses were determined over 2½ years. Differences in mineral leaching losses were not significant between treatments (total organic management: 24.2 kg N per ha; conventional management: 28.6 kg N per ha). Crop rotation and plant type had a larger influence on the microbial biomass, activity and community structure than fertilisation. Initial differences between soils decreased over time for most biological soil properties, while they persisted for the enzyme activities (e.g. dehydrogenase activity: 4.0 and 2.9 µg per g and h for organic and conventional management history, respectively). A lack of consistent positive links between enzyme activities and microbial biomass size indicated that similarly sized and structured microbial communities can express varying rates of activity. In two successive incubation experiments, the soils were amended with different rates of a lupin green manure (4 or 8t dry matter per ha), and different forms of N at 100 kg per ha (urea and lupin) and incubated for 3 months. Samples were taken periodically, and in addition to soil biological properties and community structure, gross N mineralisation was determined. The form of N had a strong effect on microbial soil properties. Organic amendment resulted in a 2 to 5-fold increase in microbial biomass and enzyme activities, while microbial community structure was influenced by the addition or lack of C or N substrate. Correlation analyses suggested treatment-related differences in nutrient availability, microbial structural diversity (species richness or evenness) and physiological properties of the microbial community. The findings of this thesis showed that using green manures and crop rotations improved soil biology in both production systems, that no relationships existed between microbial structure, enzyme activities and N mineralisation, and that enzyme activities and microbial community structure are more closely associated with inherent soil and environmental factors, which makes them less useful as early indicators of changes in soil quality.

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3

Williams, Stephen. "Soil transformations of added organic matter in organic farming systems and conventional agriculture". Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU083669.

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The aim of this work was to assay the effects of previous history of organic amendment to soils in the field on the ability of those soils to mineralise mustard, a non-legume green manure. Soil and 15N labelled mustard mineralisation was followed in laboratory microcosms. Volatilised N was assayed by direct acid trapping of N in glass fibre disks, followed by direct combustion isotope ratio mass spectrometry. Animal manures, green manures and straw added to the soil in the field in the previous season, same season and for 7 years continuously did not significantly affect these soils' ability to mineralise mustard in microcosms. Nitrification and mineralisation were the dominant processes during the first 12 days of incubation. Volatilisation rates were 1000-fold lower than mineralisation or nitrification rates. Mustard N accounted for between 1-3% of the soil mineral N, whereas only a maximum of 0.01% of mustard N was volatilised over 24 days. Soils sampled at different times in the season decomposed mustard at similar rates at stimulated low spring temperatures. Nitrification rate was reduced 5-fold more than the mineralisation rate at 8oC. Straw incorporation for seven years did not affect the subsequent recovery of 15N enriched fertiliser or of 15N from labelled straw, by oil seed rape. 15N labelled fertiliser contributed up to 63% of the winter barley N. The labelled barley straw subsequently contributed 16% of the oil seed rape N in the absence of any applied fertiliser. Ploughing in straw in the autumn, in the absence of applied fertiliser had no yield penalty or effect on crop uptake, and may retain more mineral N in the upper soil layers, lessening the risk of leaching over the winter period. The results obtained here emphasise the importance of additions of organic materials to soil in supplying plant nutrients and minimising nutrient losses.

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4

Lampkin, Nicolas. "The economic implications of conversion from conventional to organic farming systems". Thesis, Aberystwyth University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339273.

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5

Reeve, Jennifer Rose. "Soil quality, microbial community structure, and organic nitrogen uptake in organic and conventional farming systems". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Dissertations/Summer2007/j_reeve_071207.pdf.

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6

Kitchen, Julie Louise. "Nutrition and nutrional value of wheat grown in organic and conventional farming systems in South Australia". Title page, table of contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phk618.pdf.

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7

Balashova, Natalia. "Remote Sensing for Organic and Conventional Corn Assessment". Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1446803968.

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8

Gu, Yue. "Comparison between conventional and organic farming systems : an LCA study of milk production". Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292362.

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Agriculture has always been an important part in people’s daily life and has been developing over centuries with the development of technology and contributing to the rise of civilizations. Based on the production method, conventional and organic farming systems are currently the two main farming systems. The growing awareness of sustainability has forced people to think of how the future of these two farming systems would affect their sustainability performance. Swedish milk production is of high intensity and highly specialized. Swedish dairy farmers have highest milk yields in Europe, 9500 kilos per cow per year on average, and 73% of milk production takes place in the south of Sweden. The animals are kept indoors most of the year and manure is managed as slurry and removed to outdoor storage units every day. Most of the feedings are produced in Sweden, while some protein feed, especially soymeal and rapeseed meal, are imported from Brazil. Following the LCA methodology, this study aims to investigate the environmental impacts of conventional and organic milk production in Sweden, and then make a comparison between these impacts from the two systems. It also aims to find out the most influenced impact categories and the processes and activities with greatest impacts. Finally, it aims to give possible suggestions on the development of Swedish milk production systems. Methods applied in this study include a literature review of studies on milk production, especially LCA studies of milk production, and an LCA on Swedish milk production. Current LCA studies have made several improvements which are recommended in previous studies: a clear description of system boundary, a common functional unit, appropriate emission factors, and a range of impact categories. However, there are still some data gaps that need to be filled. The review shows that generally the functional unit is set to be 1 kg of energy corrected milk at farm gate, impact categories include energy use, land use, climate change, eutrophication, and acidification, cradle-to-gate boundary is used. Mass allocation, economic allocation and biological allocation are widely used. However, sensitivity analysis and uncertainty analysis are rarely conducted. LCA in this study shows that organic farming system does not have clear advantages over conventional system. Organic milk production has lower emissions in categories of CO, COD, HC, NOx, SO2, N, and P, and less use of fertilizer and pesticide. It has similar emissions of CH4, N2O, and NH3 with conventional milk production. But organic system has higher emission levels of CO2, NO3, and K, and higher land use and energy use. Looking at the corresponding ecological effects, the two systems do not have much difference in global warming, acidification, and photo-oxidant formation, while organic system has a higher eutrophication potential. To deal with environmental impacts, three types of strategies are discussed in this study. The first type concerns manure management. Improvement in manure management can reduce CH4 and N2O emissions and mitigate related ecological effects. The second one concerns milk yield, as CH4 from fermentation process, which is the main source of CH4, is lower at a higher yield. The last one is about transportation, including selecting origins of feed and transportation vehicles to reduce diesel use and replacing diesel with clean and renewable fuel.

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9

Mashele, N'wa-Jama. "Crop yields from organic and conventional farming systems in South Africa's Southern Cape". Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/11637.

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South Africa (SA) is food secure on a national level, however citizens in rural and marginalised areas face household food insecurity due to lack of access to this food. South Africa has low fertility soils and scarce water resources. Climate change reports of unpredictable weather conditions will further exacerbate these challenges. The majority of the agricultural production methods in SA are industrialised and rely heavily on external inputs. Alternative agricultural production methods which are environmentally less taxing, are affordable and yield nutritious food, need to be investigated and adopted. A long-term trial investigating the differences in yields between conventional and organic farming systems was established at the NMMU George Saasveld campus. A baseline study preceded the cropping seasons to establish pre-treatment soil conditions before the two farming systems were be implemented. The trial was a randomized complete block design split into organic, conventional and control plots. In the first cropping season (summer) three crops cabbage (Brassica oleracea var. capitata), sweet potato (Ipomea batatas) and cowpea (vigna ungucuilata) were planted under the different treatments. Soil fertility changes after application of chemical and organic fertilizer were measured. Soil pH and phosphorus increased whilst potassium and soil carbon decreased from baseline levels. The organic plots were found to have higher soil pH, potassium and carbon, whilst P was higher in the conventional plots. The organic cabbages had a yield 12% lower than conventional cabbages, organic cowpeas were 51% lower than conventional cowpeas. Baboons damaged sweet potato plots before maturity. Broccoli (Brassica oleracea var. italica), radish (Raphanus sativa) and green pea (Pisum sativum) were planted in the second cropping season (winter). Organic broccoli yields were 51% lower than conventional broccoli, organic green peas were 18 % lower than conventional green peas. The organic radish yields were 36% lower than conventional yields and this was statically significant. The yield differences were statically significant between control and conventional cabbages (25%) and broccolis (68%). The results indicate that there is on average an initial 25% yield difference between organic and conventional farming systems. Similar studies have shown that the yield gap can be reduced within three to four years. This study presents preliminary results of trials that are to continue for ten years, during which time the yield differences may vary.

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10

Demiryurek, Kursat. "The analysis of information systems for organic and conventional hazelnut producers in three villages of the Black Sea region, Turkey". Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326709.

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11

Gomes, Maryjane Diniz de AraÃjo. "Sustainability of organic and conventional family based irrigated cropping systems". Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14187.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Family farming has contributed to social development because through millions of small producers it has been a growing industry of entire relevance for the development of the country. Despite the high current production efficiency in agriculture it has been observed many environmental and social impacts, such as: soil erosion, contamination of surface and groundwater, loss of biodiversity, loss of traditional knowledge associated with economic dependence, reducing of job opportunities and income as well as rural exodus and social exclusion. For this reason, in the past few years it has been giving very strong focus on ecological benefits from cultivation of organic products. The general objective of this research is to comparatively analyze, based on indicators of economic, social and environmental indicators, two irrigated cultivation systems of organic and conventional production. The value of production and income of the farmer were respectively evaluated as variables associated to social and economic dimensions. The microbial activity of the soil was used as an environmental variable and the statistical analysis was performed using the program "ASSISTAT 7.5 BETA". The generation of direct jobs per area unit in the conventional tillage system corresponds to the reference values. Nevertheless, the organic system provides a generation of direct jobs that may reach three times the average capacity of employment generation per area unit of irrigated agriculture in the Brazilian semi-arid region, thus creating in a sustainable way, maintenance conditions for peasants. The organic system has a lower risk associated with the economic dimension compared to conventional tillage system. Current useful agricultural areas of the two production units allow them to remain in agricultural activity ensuring the social reproduction of farmers in a scenario with funding from the Pronaf. The results of the evaluated environmental variables demonstrate that production unit with organic farming has higher environmental sustainability, since the soil has good physical and chemical conditions that are more satisfactory to the development of microorganisms.
A agricultura familiar vem contribuindo para o desenvolvimento social, pois atravÃs de seus milhÃes de pequenos produtores Ã um setor em crescimento e de inteira relevÃncia para o desenvolvimento do paÃs. Apesar da elevada eficiÃncia produtiva atual na agricultura, tem se observado diversos impactos ambientais e sociais, tais como erosÃo dos solos, contaminaÃÃo das Ãguas superficiais e subterrÃneas, reduÃÃo da biodiversidade e perda de saberes tradicionais associados, dependÃncia econÃmica, reduÃÃo das oportunidades de trabalho e renda, Ãxodo rural e exclusÃo social. Por este motivo, nos Ãltimos tempos, tem se dado Ãnfase aos benefÃcios ecolÃgicos provenientes do cultivo de produtos orgÃnicos. A pesquisa tem como objetivo geral analisar comparativamente, a partir de indicadores de sustentabilidade econÃmica, social e ambiental, dois sistemas irrigados de produÃÃo, um orgÃnico o outro convencional. O valor da produÃÃo e da renda do agricultor foram avaliados como variÃveis associadas com dimensÃes sociais e econÃmicas, respectivamente. A anÃlise estatÃstica dos dados ambientais foi realizada atravÃs do programa âASSISTAT 7.5 BETAâ submetidos Ã anÃlise de variÃncia e as mÃdias comparadas pelo teste de Tukey. A geraÃÃo de empregos diretos por unidade de Ãrea no sistema de cultivo convencional corresponde aos valores de referÃncia. JÃ o sistema de cultivo orgÃnico proporciona uma geraÃÃo de empregos diretos que chega a corresponder trÃs vezes Ã mÃdia da capacidade de geraÃÃo de emprego por unidade de Ãrea da agricultura irrigada na regiÃo do semiÃrido brasileiro, criando assim de forma sustentÃvel, condiÃÃes de permanÃncia do homem no campo. O sistema de cultivo orgÃnico apresenta um menor risco associado Ã dimensÃo econÃmica comparativamente ao sistema de cultivo convencional. As superfÃcies agrÃcolas Ãteis atuais das duas unidades de produÃÃo permitem que as mesmas se mantenham na atividade agropecuÃria assegurando a reproduÃÃo social dos agricultores num cenÃrio com financiamento do Pronaf. Os resultados das variÃveis ambientais avaliadas demonstram que a unidade de produÃÃo com cultivo orgÃnico apresenta maior sustentabilidade ambiental, uma vez que o solo encontra-se em condiÃÃes fÃsicas e quÃmicas mais satisfatÃrias para o desenvolvimento dos microrganismos.

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12

Emery, E. Hayden. "Effects of Organic Versus Conventional Farming Methods on Physical and Chemical Soil Quality Indicators". The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392140957.

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13

Lévesque, Micheline. "Comparison of soil properties between conventional and organically managed farms in eastern and central France". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=67542.

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Field plots under organic and conventional management system were investigated to detect the effects of soil management practices on their soil physical, chemical and microbiological properties. The 16 farms studied, located in France, were arranged into eight matched pairs (organic/conventional).
The study revealed that in comparison with the conventionally managed soils, the organically managed soils tended to have equal to higher pH, buffering capacity, Ca, organic matter and moisture contents, and lower potential acidity values, as well as higher numbers of aerobic mesophyle and lactobacilli, and more intense alkaline phosphatase activity. The differences in soil properties between the members of matched pairs, in general were relatively small.
Soil organic matter content and nutrient availability (Ca, P), the use of lime and/or soil CaCO$ sb3$ concentrations, and use of chemical fertilizers and pesticides were found to have an influence on soil microbial activity. Soil and crop type were also found to influence some of the chemical and biological properties.

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Penfold, Christopher Morant. "The relative sustainability of organic, biodynamic, integrated and conventional broadacre farming systems in Southern Australia /". Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09AS/09asp3984.pdf.

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15

Signorotti, Claudio <1972&gt. "A farm-level programming model to compare the atmospheric impact of conventional and organic farming". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/6017/.

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A model is developed to represent the activity of a farm using the method of linear programming. Two are the main components of the model, the balance of soil fertility and the livestock nutrition. According to the first, the farm is supposed to have a total requirement of nitrogen, which is to be accomplished either through internal sources (manure) or through external sources (fertilisers). The second component describes the animal husbandry as having a nutritional requirement which must be satisfied through the internal production of arable crops or the acquisition of feed from the market. The farmer is supposed to maximise total net income from the agricultural and the zoo-technical activities by choosing one rotation among those available for climate and acclivity. The perspective of the analysis is one of a short period: the structure of the farm is supposed to be fixed without possibility to change the allocation of permanent crops and the amount of animal husbandry. The model is integrated with an environmental module that describes the role of the farm within the carbon-nitrogen cycle. On the one hand the farm allows storing carbon through the photosynthesis of the plants and the accumulation of carbon in the soil; on the other some activities of the farm emit greenhouse gases into the atmosphere. The model is tested for some representative farms of the Emilia-Romagna region, showing to be capable to give different results for conventional and organic farming and providing first results concerning the different atmospheric impact. Relevant data about the representative farms and the feasible rotations are extracted from the FADN database, with an integration of the coefficients from the literature.

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Lipai, Monica. "Socioeconomic comparisons of organic and conventional farms in Canada : results from the 2001 Census". Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101864.

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This thesis examines differences between organic and conventional farm and operators' characteristics, and identifies which characteristics explain whether a farm is organic or conventional. The data comes from the 2001 Canadian Census of Agriculture, which makes this study the first that is national in scope and includes detailed analysis of the differences between organic and conventional agriculture using a large sample size.
Farms were divided into three groups: conventional, primarily organic, and mixed production (some organic production). Parametric and nonparametric tests were used to analyze farm and operator characteristics. Logistic regression was used to determine which variables explain whether a farm is organic, conventional or mixed. Results indicate that organic farmers are more likely to be younger, female, work less off farm and more on farm, when compared to conventional. Organic farms tend to be smaller, more profitable, more diversified, and have a higher dependency on hired labour. There were no differences in capital intensity. Mixed farms manifested the same patterns as organic when compared to conventional.

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17

Pollnac, Fredric Winslow. "Diversity, spatial patterns, and competition in conventional no-tillage and organically managed spring wheat systems in Montana". Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/pollnac/PollnacF0507.pdf.

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18

Stark, Christine H. "Effects of long- and short-term crop management on soil biological properties and nitrogen dynamics". Lincoln University, 2005. http://hdl.handle.net/10182/30.

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To date, there has been little research into the role of microbial community structure in the functioning of the soil ecosystem and on the links between microbial biomass size, microbial activity and key soil processes that drive nutrient availability. The maintenance of structural and functional diversity of the soil microbial community is essential to ensure the sustainability of agricultural production systems. Soils of the same type with similar fertility that had been under long-term organic and conventional crop management in Canterbury, New Zealand, were selected to investigate relationships between microbial community composition, function and potential environmental impacts. The effects of different fertilisation strategies on soil biology and nitrogen (N) dynamics were investigated under field (farm site comparison), semi-controlled (lysimeter study) and controlled (incubation experiments) conditions by determining soil microbial biomass carbon (C) and N, enzyme activities (dehydrogenase, arginine deaminase, fluorescein diacetate hydrolysis), microbial community structure (denaturing gradient gel electrophoresis following PCR amplification of 16S and 18S rDNA fragments using selected primer sets) and N dynamics (mineralisation and leaching). The farm site comparison revealed distinct differences between the soils in microbial community structure, microbial biomass C (conventional>organic) and arginine deaminase activity (organic>conventional). In the lysimeter study, the soils were subjected to the same crop rotation (barley (Hordeum vulgare L.), maize (Zea mais L.), rape (Brassica napus L. ssp. oleifera (Moench)) plus a lupin green manure (Lupinus angustifolius L.) and two fertiliser regimes (following common organic and conventional practice). Soil biological properties, microbial community structure and mineral N leaching losses were determined over 2½ years. Differences in mineral leaching losses were not significant between treatments (total organic management: 24.2 kg N ha⁻¹; conventional management: 28.6 kg N ha⁻¹). Crop rotation and plant type had a larger influence on the microbial biomass, activity and community structure than fertilisation. Initial differences between soils decreased over time for most biological soil properties, while they persisted for the enzyme activities (e.g. dehydrogenase activity: 4.0 and 2.9 µg g⁻¹ h⁻¹ for organic and conventional management history, respectively). A lack of consistent positive links between enzyme activities and microbial biomass size indicated that similarly sized and structured microbial communities can express varying rates of activity. In two successive incubation experiments, the soils were amended with different rates of a lupin green manure (4 or 8t dry matter ha⁻¹), and different forms of N at 100 kg ha⁻¹ (urea and lupin) and incubated for 3 months. Samples were taken periodically, and in addition to soil biological properties and community structure, gross N mineralisation was determined. The form of N had a strong effect on microbial soil properties. Organic amendment resulted in a 2 to 5-fold increase in microbial biomass and enzyme activities, while microbial community structure was influenced by the addition or lack of C or N substrate. Correlation analyses suggested treatment-related differences in nutrient availability, microbial structural diversity (species richness or evenness) and physiological properties of the microbial community. The findings of this thesis showed that using green manures and crop rotations improved soil biology in both production systems, that no relationships existed between microbial structure, enzyme activities and N mineralisation, and that enzyme activities and microbial community structure are more closely associated with inherent soil and environmental factors, which makes them less useful as early indicators of changes in soil quality.

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Wander, Michelle Mary. "The effects of organic and conventional corn-soybean rotations on soil organic matter characteristics : the Rodale farming systems trial experiment /". The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487780865411828.

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Brown, Nicola Jane. "Carabid ecology in organic and conventional farming systems : population density, diversity and high resolution spatial dynamics". Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340435.

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Bražinskienė, Vaiva. "The effect of organic and conventional farming types on the amount of antioxidant compounds in potato tubers". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140522_135753-68336.

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Research objective. To investigate the effects of organic and conventional farming types on antioxidant activity of potato tubers and on the amounts of accumulated amino acids (tyrosine and tryptophan) and phenolic compounds. Research tasks 1. To develop and validate the HPLC method for quantification of phenolic compounds, tyrosine and tryptophan, accumulated by potatoes. 2. To investigate the effects of organic and conventional farming types, properties of a variety, and tuber time of maturity on the amounts of tyrosine, tryptophan, and phenolic compounds accumulated in potato tubers. 3. To evaluate the impacts of organic and conventional farming types on total antioxidant activity of potato tubers. 4. To determine the prevailing compounds with antioxidant activity accumulated in potato tubers, and quantify of their antioxidant activity. 5. To evaluate the influence of storage time on the amount of the accumulated phenolic compounds in organically and conventionally grown potato tubers. Research subject. Potato (Solanum tuberosum L.) tubers of several varieties with different time of maturity: • Very early: ‘VB Venta’, ‘Fresco’, ‘Acapella’ • Early: ‘Santa’, ‘Goda’, ‘VB Liepa’ • Medium: ‘Lady Rosetta’, ‘Red Lady’, ‘Courage’ • Late: ‘VB Rasa’, ‘VB Aista’, ‘Saturna’ Originality of the research work. The effects of organic and conventional farming types, tuber time of maturity, and properties of a potato variety on the amount of antioxidant compounds accumulated in potato... [to full text]
Darbo tikslas. Ištirti ekologinės ir intensyviosios žemdirbystės sistemų įtaką bulvių gumbų antioksidaciniam aktyvumui ir jų kaupiamų amino rūgščių (tirozino ir triptofano) ir fenolinių junginių kiekiui. Uždaviniai 1. Sukurti ir validuoti ESC metodiką bulvių kaupiamų fenolinių junginių, tirozino ir triptofano kiekybiniam įvertinimui. 2. Ištirti ekologinės ir intensyviosios žemdirbystės sistemų, veislės savybių ir gumbų subrendimo laiko įtaką bulvių gumbų kaupiamų tirozino, triptofano ir fenolinių junginių kiekiui. 3. Įvertinti ekologinės ir intensyviosios žemdirbystės sistemų įtaką suminiam bulvių gumbų antioksidaciniam aktyvumui. 4. Nustatyti dominuojančius bulvių gumbų kaupiamus antioksidaciniu aktyvumu pasižyminčius junginius ir kiekybiškai įvertinti jų antioksidacinį aktyvumą. 5. Įvertinti sandėliavimo trukmės įtaką ekologiškai ir intensyviai augintų bulvių gumbų kaupiamų fenolinių junginių kiekiui. Tyrimo objektas. Skirtingo subrendimo laiko įvairių veislių valgomųjų bulvių (lot. Solanum tuberosum L.) gumbai: • Labai ankstyvos: ‘VB Venta’, ‘Fresco’, ‘Acapella’ • Ankstyvos: ‘Sante’, ‘Goda’, ‘VB Liepa’ • Vidutinio ankstyvumo: ‘Lady Rosetta’, ‘Red Lady’, ‘Courage’ • Vėlyvos: ‘VB Rasa’, ‘VB Aista’, ‘Saturna’ Mokslinio darbo naujumas. Ištirta ekologinės ir intensyviosios žemdirbystės sistemos, gumbų subrendimo laiko ir veislės įtaka bulvių gumbų kaupiamų antioksidacinių junginių kiekiui. Įvertintas bulvių gumbų antioksidacinis aktyvumas ekologiškai ir intensyviai augintuose... [toliau žr. visą tekstą]

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Luangtongkum, Taradon. "Campylobacter spp. in conventional and organic poultry operations". Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1123790867.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xii, 304 p.; also includes graphics. Includes bibliographical references (p. 253-304). Available online via OhioLINK's ETD Center

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Potenza, Sarah Lynne. "Action-oriented sustainable agriculture education attitudes towards nutrition and agricultural practices in Guaimaca, Honduras /". CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05222007-131327/.

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24

Bulová, Jitka. "Možnosti marketingové orientace na trhu bioproduktů". Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-77769.

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Diploma thesis on the topic of possibilities of marketing orientation on the organic market deals with organic farming and organic food. The first part is to get familiar with this issue. There are characterized differences between organic and conventional farming, the advantages and disadvantages of organic farming, animal and plant specifications of production, conditions that must be met if the transition from conventional to organic farming, the follow-up compliance with the conditions laid down by law. Another section is devoted to organic food and their characterization, organic certification and marketing. The practical part includes its own investigation with an awareness of consumers about organic food. The conclusion gives the specifics of organic farming and organic food, and based on the analysis and possible recommendations on marketing orientation.

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25

Länn, Andreas, e Philip Wikholm. "To be, or not to be, organic : Motives and barriers for Swedish wine farmers to use organic practices". Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388869.

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Wine production is one of the farming practices with the highest negative environmental impacts, mainly due to a heavy use of pesticides, why it is important to find more sustainable wine production practices. One such practice is organic farming, but the transition is slow and the number of organic certified vineyards remain low. The purpose of this study is to map what motives and barriers Swedish wine farmers perceive in using organic practices in their production, and to what extent the decision to do so is guided by intrinsic or extrinsic motivation. This was studied by visiting 11 Swedish vineyards and conducting interviews with the wine farmers. The theoretical framework used in this thesis builds on the Self-determination theory about motivation together with previous research on motives and barriers to convert to organic farming. The results show that despite that only 5% of the Swedish vineyards are organically certified, all visited vineyards almost exclusively use organic practices in their production. The main motives to use organic practices were identified to be soil protection and long-term scope of the vineyard, biodiversity and ecosystem protection, lower exposure to agrochemicals, to produce an honest product, and the possibility of increased sales. Perceived barriers with using organic practices among Swedish wine producers were increased workload and labour costs, lack of access to knowledge about organic viticulture, difficulties with weed and pest control, and lower harvest yields. The decision to use organic practices are mainly guided by inner beliefs about producing the wine in harmony with nature, not causing unnecessary damage, producing a high-quality product they can be proud of, and the desire to get a professional challenge and develop as winemakers, consequently indicating that Swedish wine farmers are motivated by intrinsic motivation. Only weak indicators of extrinsic motivation were found in the study. Furthermore, the study found that the climate in southern Sweden is facilitating for organic viticulture which together with a lack of regulations regarding grape- and vine varieties could act as a foundation for Sweden to become a leader in sustainable wine production, but that a lack of knowledge and the strict regulation on sales of alcohol might prevent this.

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26

Kandil, Mohamed Ali Mahmoud Hussein. "The effect of fertilizers for conventional and organic farming on yield and oil quality of fennel (Foeniculum vulgare Mill.) in Egypt". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964677806.

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27

Musyoka, Martha [Verfasser], e Georg [Akademischer Betreuer] Cadisch. "Nitrogen dynamics in organic and conventional farming systems in the sub-humid highlands of central Kenya / Martha Musyoka ; Betreuer: Georg Cadisch". Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2019. http://d-nb.info/1193125510/34.

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28

Gabriel, Doreen. "Plant communities in organic and conventional agriculture comparing local, landscape and regional effects /". Doctoral thesis, [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/gabriel.

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29

Klang, Linda. "Opportunities and obstacles in the certification process : A case study on the development of the organic production and agriculture in Babati, Tanzania". Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-6419.

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Organic products have become more and more talked- about in today’s industrial world. The demand for organic products is increasing and the market is continuing to grow bigger. It is important to maintain what these products stand for, being environmental friendly, and to do so strict certification policies are needed. EU has today an international certification body called Regulation (EC) 834/2007 that needs to be followed for export to and within EU. Parts of Tanzania today have certification of some organic products but not in Babati, that lies in the northern of Tanzania in Manyara region where this case study was done. In Babati most of the farmers are smallholder farmers and many of them, founds it difficult to afford an international certification. For the smallholder farmers to get a certification there are two alternatives. One is to go together with other smallholder farmers and apply for a certification like EUs Regulation (EC) 834/2007 as a group and then get to pay lower fees. The other alternative is to go together and start local certification bodies that have fees that are adjusted to local farmers’ income. This case study was conducted between February and March of 2010 in villages around Babati and Babati town. Interviews were held with both organic- and non organic farmers. My goal was to find out if it was possible for Babati to develop the organic agriculture and have an organic market in the future. My conclusion ends up by perceiving that Babati has a very good chance of fulfilling the Regulation (EC) 834/2007 standards. However the farmers’ economical status is an obstacle for the farmers to get an international certification, because of the high cost in inspections and reinspections. But through a local certification body that is adjusted to the smallholder farmers and the environment the farmers can get their certificate and the organic market can be developed in Babati.

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30

Bartušková, Alena. "Manažerské hodnocení perspektiv ekologického zemědělství". Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-136213.

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The thesis focuses on the possibilities of further development of conventionally employed family farm. Form of a business plan is described and analyzed baseline farms, its specific features, options, and its position within the industry. The output is an evaluation of the proposed options, possible future development by financial remuneration and other entitlements to individual alternatives. Work is processed in order to verify whether the proposed project from the economic point of view actually realize.

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31

Jandovský, Martin. "Inga miljövinster med ekologisk produktion? : Lägesrapport över den svenska jordbruksdebatten". Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-13863.

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Organic agriculture is financially promoted in Sweden by special environmental support and as consumers we are all encouraged to buy organic food. At the same time scholars at the Swedish University of Agricultural Sciences claim that organic farming does not provide any environmental benefits. The main criticism is that organic farming has lower yields than conventional, which means that more land is needed to produce the same amount of food as in conventional farming, leading to deforestation and loss of biodiversity. As for climate change, the critics claim that the significantly higher productivity in conventional crop production compared to organic, releases surplus land, which could be used for bio-fuel production and thereby replace the fossil fuels. The critics also claim that organic farming causes higher nutrient leaching than conventional. Scholars who advocate organic farming fight back against the criticisms and claim; that organic farming benefits biodiversity, as organic farms have on average 30% higher species richness than conventional farms, that conventional farming due to fertilizer use causes higher green house gas emissions than organic, and that the conventional farming causes higher nutrient losses than the organic one from a system perspective. The purpose of this essay is to present and analyze arguments of both sides of the Swedish agricultural debate and try to find answers to how scholars can have such widely differing views about which farming-system is preferable. At first glance, it may seem as if scholars totally disagree on the issues regarding scientific facts. This essay however, suggests that this is not the case at all. On the contrary, scholars agree on quite a lot when it comes to facts. The reasons for disagreement appear to be about much more than just a scientific controversy. My explanation to how they can have such different views is that agriculture, to a large extent, is a social and political issue, which means that scholars' values and view of nature also play a crucial role in their overall perception.

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32

Wilkinson, Sarah. "Nitrate and ammonium levels as an indication of soil fertility : an investigation into the soil fertility of organic versus conventional soil management practices". Thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/23939.

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33

Sanderson, Bellamy Angelina. "Costa Rican coffee and bananas : A social-ecological study of management practices and their effects on the environment". Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-61221.

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This thesis investigates the variability in management practices on coffee and banana farms in an attempt to identify practices that reduce the environmental impact of export crop production. Different banana production systems are studied to determine their level of environmental impact. Insect sampling and bird surveys are used to assess the level of ecological quality on banana farms and their surrounding environments. The first two studies are based on interview methods and focus more on the social aspects of the production system. Paper I identifies how farmers utilize labor and herbicides in weed control practices, and found that small-scale coffee farmers overuse herbicides when their relative use of herbicides to labor to control weed densities is compared to their large-scale counterparts and small-scale organic producers. Paper II attempts to identify variability in management practices for the production of export bananas, but instead finds that there is only one type of export banana production system. However, there are lessons to be learned from organic and banana-coffee intercropping systems of production. Papers III-V use the information gathered in the interview studies of Paper II to give context to the results from analysis of ecological indicators collected from banana farms. Paper III is a comparison of insect community composition on high-input, low-input and organic banana farms. Paper IV is an analysis of aquatic macroinvertebrate in surface water sites upstream and downstream of banana farm canal entry points. Finally, Paper V is a comparison of ecological effects of management practices between Rainforest Alliance certified farms and non-RainforestAlliancecertified farms. Results showed that low-input banana production is not as good as organic production with regards to ecological impact, but it can still make a difference when compared to high-input banana production. Rainforest Alliance certified farms, however, are not low-input systems and the changes that they make in production practices are not enough to influence the quality of the ecological system. These results are encouraging for low-input production systems, but show that standards for Rainforest Alliance certification need to be tougher in order to make an impact on ecological indicators.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. Paper 4: Submitted. Paper 5: Manuscript.

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34

Larsson, Ahlqvist Andreas, e Sofia Wahlström. "Det ekologiska steget : En studie kring hinder och drivkrafter för lantbrukares val att bedriva ekologisk livsmedelsproduktion i Östergötland". Thesis, Linköpings universitet, Institutionen för tema, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119006.

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Denna studie syftar till att identifiera vad det är som driver eller hindrar lantbrukare i Östergötland att ställa om sitt lantbruk till ekologisk produktion och huruvida de identifierade påverkningsfaktorerna skiljer sig åt mellan konventionella och ekologiska lantbrukare. Semistrukturerade intervjuer med tre konventionella samt fyra ekologiska lantbrukare genomfördes för att undersöka deras erfarenheter. Respondenternas erfarenheter redovisas i sex identifierade teman; Gårdsspecifika förutsättningar, Ekonomi, Politik, Administration och regelverk, Miljö och hälsa samt Produktionsteknik. En jämförelse mellan de båda grupperna genomförs och det empiriska materialet ställs mot tidigare forskning. Resultatet av studien visar att skillnader mellan ekologiska och konventionella lantbrukares uppfattningar kring hinder och drivkrafter förekommer, men inte inom alla teman. Det är tydligt att lönsamhet är viktigt för att lantbrukare skall ställa om sin produktion men även andra faktorer påverkar valet och behöver beaktas om en ökad konvertering är önskvärd.
This study aims to identify motivations and barriers for farmers in Östergötland regarding conversion to organic farming and if the identified factors of influence differ between the conventional and the organic farmers. We used semi-structured interviews with three conventional farmers and four organic farmers to examine their personal experience regarding organic farming. The experiences from the respondents are presented in six identified themes: Farm specific conditions, Economy, Politics, Administration and regulations, Environment and health and Production techniques. This is followed by a comparison between the groups, and the empirical material is linked to scientific sources on the subject. The result of the study indicates that differences between identified motivations and barriers exists between the two groups, but not within every theme. It is clear that profitability is an important factor for farmers to convert their production, but other factors may influence the choice as well. It is necessary to consider these factors if an additional increase in organic farming is desired.

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35

Albertus, Randal Marius Colin. "The influence of different management practices on soil faunal activity in vineyard soils". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53129.

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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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Gao, Ze. "Organic Farming is Coming to Our Valley : The Development of Pumi Eco-Agriculture and the Indigenisation of Modernity in Sino-Myanmar Borderlands". Thesis, Uppsala universitet, Institutionen för arkeologi och antik historia, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388436.

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How do indigenous people perceive and practice eco-agriculture, especially when it was introduced as a development project? This thesis aims to delve into this question by focusing on a policy-induced agrarian transition for Pumi community in Sino-Myanmar borderlands. Using ethnographic methods, I intend to offer an intimate account of a provincial programme to facilitate eco-agriculture in this ethnic region. With the conceptual framework presented, the current research starts with the introduction of Pumi agricultural history and indigenous farming knowledge, with a focus on Pumi biocultural heritage. Then, I will examine how the process of ‘indigenisation of modernity’ (Sahlins 2000) has occurred against the backdrop of Pumi eco-agriculture programme. The insights will be distilled from three different aspects, which are agricultural land use, technical practices, and governance issues. For each aspect, I will scrutinise to what degree the government is following an industrial model to design the eco-agriculture agenda which corresponds to the ‘conventionalisation hypothesis’ of organic production (Buck 1997) and is thus in alignment with their long-term strategic goals to ‘modernise’ this borderland region through agricultural transformations, whereas the local Pumi farmers are actively coping with the government’s external interventions, meanwhile searching for the ‘alternative pathway’ towards agricultural modernisation. In the final chapter, I will interpret the motives of the both actors in the programme. For the government, the post-development theory will be employed to provide a critique of the ‘development discourse’ embedded in the agenda. For local farmers, the concept of ‘environmentality’ (Agrawal 2005) will be focused to interpret the Pumi farmers’ motives to indigenise, which ultimately questioning the transforming powers of modernity and globalisation on Pumi agrarian society. Basically, this thesis aims to trace the socio-political processes which drive the ‘agrarian transition’ in a Southeast Asian frontier, and further demonstrate how the resource abundance in the borderlands can underpin intense processes of commodification and dispossession (Nevins and Peluso 2008; Ishikawa 2010; see also Milne and Mahanty, 2015), the implications of which crystallised in an ethnographic context. To a larger extent, this research aims to shed lights on the interactions between social structure and individual agency ― although the Pumi farmers are struggling to survive with the adaptation to modern inputs, they are still marginalised by the structured inequality of the market economy, which limited the farmers’ opportunities to improve their own livelihoods. Furthermore, this research also has significant policy implications as it addresses the issues such as agricultural policy and ethnic relations in the borderland regions. By reflecting upon the overlapping implications of highland livelihoods, agencies, and the transforming powers of social change, the current study aims to build a locally rooted understanding of Pumi eco-agriculture programme, and provide lessons for sustainable planning and future policy-making for rural development in developing countries such as China.

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37

Sikorskytė, Aušra. "Auginimo technologijų įtaka 'Elise' obuolių kokybei". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_153932-61327.

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Sikorskytė A. Auginimo technologijų įtaka 'Elise' obuolių kokybei: Ekologijos specialybės agroekologijos specializacijos magistro darbas / Vadovė V. Rutkovienė; LŽŪU. – K., 2007 – 54 p.: 16 pav., 15 lentelių, 2 priedai. Bibliogr.: 63 pav. SANTRAUKA Magistratūros studijų baigiamajame darbe tiriama auginimo technologijų įtaka Elise obuolių kokybei. Darbo objektas – Malus genties augalo vienos Elise veislės vaisiai, brandinami obelų, kurios auga Kauno kolegijos Kraštotvarkos fakulteto mokomajame – pomologiniame sode (Mastaičiai, Kauno r.). Minėtos veislės obelys auginamos ekologinėmis ir įprastinėmis sąlygomis. Darbo tikslas – įvertinti auginimo technologijų įtaką Elise obuolių kokybei. Darbo metodai – eksperimentinis, atlikti elektrocheminiai ir cheminiai kokybės tyrimai, mokslinės literatūros ir tyrimo duomenų analizė. Darbo rezultatai. Įprastinėmis ir ekologinėmis sąlygomis augintų obuolių kokybė vertinta pagal elektrocheminius, fizinius ir cheminius parametrus. Nustatyta, kad gausesnį derlių subrandino įprastinėmis sąlygomis augančios obelys. Nustatyti koreliaciniai ryšiai tarp elektrocheminių ir fizinių parametrų: stiprūs atvirkštiniai ryšiai yra tarp vaisiaus skersmens (r =-0,88), masės (r =-0,77) ir elektrinio laidžio; atvirkštiniai koreliaciniai ryšiai tarp vaisiaus skersmens ir P vertės (r = -0,85) bei vidutinio stiprumo atvirkštiniai koreliaciniai ryšiai tarp vaisiaus masės ir P vertės (r = -0,67). Esminiai skirtumai nustatyti tarp cheminės sudėties (bendrojo... [toliau žr. visą tekstą]
Sikorskytė A. Growing technologies influence on quality of apple ‘Elise’: the final work of Master’s Degree Studies of Agro ecology specialisation of Ecology speciality/ Supervisor V. Rutkovienė; LŽŪU. – K., 2007 – 54 pages: 16 pictures, 15 tables, 2 annexes, 63 literature sources. SUMMARY The final work of Master Degree Studies is based on the research of influence of growing technologies on quality of apple variety Elise. The object of the final work – As an object of the research fruits of one variety Elise of genus Malus plants were selected. Following plants are growing in the educational – phomological garden of Landscape faculty of college of Kaunas (Mastaičiai, Kaunas district). Apple trees of variety Elise are grown under organic and conventional conditions. The aim of the final work – to evaluate the influence of growing technologies on the quality of apple fruits Elise. Methods of the final work – experimental; electrochemical and chemical research of quality has been made; the analysis of science literature and data of research. Result of the final work. The quality of organic farming and conventionally grown apple fruits has been evaluated according to electrochemical, physical and chemical characteristics. Judging by the results obtained the yield from conventional apple trees has been bigger then those grown by the organic farming. The correlation between electrochemical and physical results has been obtained as follows: strong converse relations are among... [to full text]

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Roschewitz, Indra. "Farming systems and landscape context effects on biodiversity and biocontrol /". Doctoral thesis, [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976217961.

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Muneret, Lucile. "Déploiement de l’agriculture biologique à l’échelle du paysage : impacts sur les communautés d’ennemis naturels et les services de régulation des bioagresseurs". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0031/document.

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Identifier les leviers permettant de stimuler la régulation naturelle des bioagresseurs tout en préservant la biodiversité est indispensable pour concevoir des paysages agricoles fonctionnels. A partir d’une méta-analyse et d’une étude empirique reposant sur 42 parcelles viticoles localisées dans Nouvelle Aquitaine (France), nous avons cherché à évaluer l’impact du déploiement de l’agriculture biologique à de large échelles spatiales sur 1) les communautés d’ennemis naturels, 2) les services de régulation naturelle, 3) les taux d’infestation par les bioagresseurs. Dans ce travail, nous avons montré que la proportion d’agriculture biologique est un facteur structurant plus les communautés d’ennemis naturels que la proportion d’habitats semi-naturels dans le paysage. De plus, nous avons montré que les communautés de bioagresseurs rencontrées dans les vignes ne sont pas influencées par la proportion d’agriculture biologique alors qu’elles répondent plutôt négativement à la proportion d’habitats semi-naturels. Par ailleurs, nous avons montré que l’agriculture biologique, à l’échelle globale et indépendamment du type de culture considérée est un système de culture stimulant la régulation naturelle des bioagresseurs. En viticulture, elle permet de réduire l’utilisation des produits phytosanitaires, comparé à l’agriculture conventionnelle. Enfin, nos analyses ont révélé qu’au-delà de la différence de systèmes de culture, un certain nombre de facteurs locaux (e.g., âge des parcelles, fréquence de traitements, productivité) permettent d’expliquer la structure des communautés d’ennemis naturels et des services de régulation naturelle des bioagresseurs. Tout en produisant des connaissances sur les processus permettant d’expliquer les assemblages des communautés d’ennemis naturels et les niveaux de services de régulation rendus, notre travail suggère des pistes pour l’aménagement des paysages viticoles permettant de concilier préservation de la biodiversité et maximisation des régulations naturelles
Identifying landscape context and farming systems that enhance natural pest control while maintaining biodiversity is crucial to design functional agricultural landscapes. Using a meta-analysis and an empiric study based on 42 vineyards in Nouvelle Aquitaine (France), we investigated the effect of the deployment of organic farming at a landscape scale on 1) natural enemy communities, 2) natural pest control and 3) pest infestation levels. Here, we showed that the proportion of organic farming structured more natural enemy communities than the proportion of semi-natural habitats. On the opposite, pest and pathogen infestations were never influenced by the proportion of organic farming while they were negatively influenced by the proportion of semi-natural habitats. Furthermore, at a global scale and for every crop types, organic farming, per se, enhances natural pest control. In viticulture, it is less dependent of synthetic agrochemicals than conventional farming. Moreover, local factors such as the treatment frequency index, the field age and the crop productivity had important effects on natural enemy communities and natural pest control. Finally, we yielded knowledge on processes that impact natural enemy assembly and natural pest control in agrosystems. For vineyards-dominated landscapes, our work suggests some tracks for landscape planning that support biodiversity conservation and natural pest control

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Djoudi, El Aziz. "Structuration multi-échelle des communautés d'Arthropodes en agro-écosystèmes". Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B056.

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Au cours de ce travail, nous nous sommes intéressés à l’influence des conditions locales et paysagères sur la structuration des communautés d’arthropodes en agroécosystèmes, ceci grâce à un dispositif de suivi situé en Ille-et-Vilaine (Bretagne, France), et comprenant des parcelles conduites en agriculture biologique et conventionnelle spatialement appariées. Notre première étude a mis en évidence que l’hétérogénéité paysagère, parfois en interaction avec le système local de culture, conditionne la diversité et l’abondance des groupes trophiques, à la fois pour les arthropodes au sol comme pour ceux de la végétation. Dans un second temps, nous avons pu montrer l’importance du contexte paysager dans la structuration des assemblages d’arthropodes prédateurs, et émis l’hypothèse que les mécanismes déterminant la distribution des espèces diffèrent fortement entre araignées et carabiques. Enfin, il est apparu la nécessité de distinguer les individus résidents (émergeants) des individus mobiles (circulants) lorsque l’on s’intéresse au rôle différentiel des facteurs locaux vs. paysagers dans la structuration des communautés de carabiques. D’une façon générale, nos résultats montrent donc une influence importante et positive de l’agriculture biologique sur les populations, assemblages d’espèces et communautés d’arthropodes, que ce soit à des échelles locales et paysagères comme en interaction avec d’autres variables paysagères. Nous avons également montré la pertinence de l’utilisation de différents niveaux d’organisation et variables réponses associées pour évaluer finement la structure et le fonctionnement de communautés d’Arthropodes en agroécosystèmes
In this study, we got interested in quantifying how local and landscape metrics structure arthropod communities in agro-ecosystems. For that, we used a long-term monitoring design located in ‘Ille-Et-Vilaine’ (Brittany, France), composed by spatially pair-matched fields under organic vs. conventional farming systems. First, we found that landscape heterogeneity, also interacting with farming systems, drives the diversity and abundance of trophic groups for both ground- and vegetation-dwelling arthropods. In a second chapter, we showed the importance of landscape context in shaping assemblages of predatory arthropods, and suggested that mechanisms behind the distribution of individual species strongly differ between spiders and carabids. Lastly, we highlighted the importance of distinguishing between resident (emergent) and mobile (circulating) individuals when assessing the differential role of local vs. landscape factors in community assembly. Overall, our results show a strong and positive effect of organic farming on arthropod populations, assemblages and communities, both at local and landscape scales, as well as in interaction with other landscape metrics. We also highlighted the relevance of using different levels of biological organization, and related response variables, when assessing the structure and functioning of arthropod communities in agroecosystems

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Ksenija, Čobanović. "Sadržaj uree u mleku, parametri plodnosti i mlečnosti holštajn frizijskih krava u organskoj i konvencionalnoj proizvodnji". Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=101573&source=NDLTD&language=en.

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Urea kao deo neproteinske frakcije azota mleka, predstavlja krajnji produkt metabolizma proteina u predželucima preživara. Portalnim krvotokom toksični amonijak, nastao mikrobiološkom razgradnjom proteina u rumenu dolazi do jetre gde se transformiše u ureu, koja kasnije krvotokom dospeva u mleko. Ishrana, odnosno sadržaj sirovih proteina u obroku ima najveći uticaj na sadržaj uree u mleku. Sadržaj uree sve više se koristi kao parametar pomoću kojeg je moguće pratiti unos sirovih proteina i energije obrokom kod mlečnih krava. Pored ishrane na sadržaj uree u mleku utiču i drugi faktori, kao što su sezona, prinos mleka, stadijum laktacije, paritet i dr.Plodnost krava je veoma važna osobina mlečnih goveda na koju utiče veliki broj faktora. Dosadašnja istraživanja u ovoj oblasti ukazuju na moguću vezu između plodnosti krava i sadržaja uree u mleku.Određivanje sadržaja uree u mleku primenom infracrvene spektrofotometrije u analizi mleka prilikom redovne mesečne kontrole mlečnosti krava pružilo je nove mogućnosti u praćenju kvaliteta mleka.Cilj ovog istraživanja bio je da se utvrdi:1. variranje sadržaja uree u mleku unutar stada,2. uticaj paragenetskih faktora (farma, sistem proizvodnje, sistem držanja, sezona, redni broj laktacije i stadijum laktacije) na sadržaj uree u mleku,3. korelacija sadržaja uree sa parametrima mlečnosti krava i brojem somatskih ćelija i4. korelacija između sadržaja uree u mleku i dužine servis perioda.U okviru ovog istraživanja analizirano je 46.315 uzoraka mleka, u okviru redovne kontrole mlečnosti, sa 11 farmi sa područija Vojvodine. Od kojih je jedna sa organskom, a 10 farmi sa konvencionalnom proizvodnjom. Određivanje sadržaja uree u mleku vršeno je na aparatu MilcoScan.Prosečan sadržaj uree u mleku (25,18 mg/dl) bio je u okviru optimalnih vrednosti sadržaja uree u mleku. Koeficijent varijacije za sadržaj uree (34,15%) bio je znatno veći od koeficijenta varijacije za ostale sastojke mleka.Dobijeni rezultati u okviru ove doktorske disertacije ukazuju da najveći uticaj na sadržaj uree u mleku ima menadžment farme. Utvrđen je i statitički značajan uticaj ostalih ispitivanih paragenetskih faktora.Sistem držanja statistički značajno utiče na sadržaj uree u mleku. Niži sadržaj uree u mleku bio je kod krava u slobodnom sistemu držanja.Kao posledica specifičnosti organske proizvodnje konstatovane su statistički značajne razlike između organske i konvencionalne proizvodnje mleka. Razlike se ogledaju u smanjenom sadržaju uree u mleku i prinosu mleka, a povećanom sadržaju mlečne masti i proteina. Broj somatskih ćelija u mleku iz organske proizvodnje je znatno manji u odnosu na broj istih u mleku iz konvencionalne proizvodnje mleka, dok je servis period u posmatranom periodu bio duži kod krava u organskoj proizvodnji u odnosu na krave u konvencionalnoj proizvodnji mleka.Posmatrano po sezonama kontrole najniži sadržaj uree u mleku bio je u jesenjem periodu (22,19 mg/dl), a najveći u letnjem period (27,11 mg/dl). Razlike u sadržaju uree po laktacijama su male, ali statistčki značajne.Konstatovan je statistički značajan uticaj stadijuma laktacije na sadržaj uree u mleku. Najniži sadržaj bio je na početku laktacije (23,05 mg/dl), a maksimalan sadržaj uree u mleku od 26,40 mg/dl, bio je od 121 do 180 dana laktacije.Utvrđene su pozitivne, statistički visoko značajne, korelacije između sadržaja uree i pojedinih sastojaka mleka, kao i između sadržaja uree i prinosa mleka. Korelacija između sadržaja uree i broja somatskih ćelija u mleku je negativna i visoko statistički značajna.U okviru ovog istraživanja utvrđena je pozitivna i statistički visoko značajna korelacija između sadržaja uree u mleku i dužine servis perioda.Dobijeni rezultati, tumačeni u kontekstu drugih istraživanja na ovu temu ukazuju na veliki značaj praćenja sadržaja uree u mleku, koji može doprineti poboljšanju menadžmenta ishrane i reprodukcije na farmama mlečnih krava, a sve u cilju smanjenja troškova na farmama, kroz smanjenje troškova ishrane i troškova veterinarskih usluga.
Urea as a part of non-protein fraction of nitrogen in milk represents the final product of protein metabolism in the rumen of ruminants. By portal bloodstream toxic ammonia comes into liver where it is transformed into urea, which comes later into milk by bloodstream. Nutrition and contents of crude proteins in the diet have the greatest influence on the milk urea content. The content of milk urea has been increasingly used as a parameter by which it is possible to monitor balance of energy and crude proteins in the feed of dairy cows.Apart from feeding, milk urea content can be influenced by some other factors as season, milk yield, stage of lactation, parity etc.A great number of factors influence cow’s fertility. Previous research in this field has indicated a possible relationship between the fertility of cows and urea content in milk.Determination of urea content in milk, by infrared spectrophotometric, on monthly bases, for milk recording porpoises, offers new opportunities for milk quality monitor.The aim of this study was to determine:1. Variations of milk urea content within the herd,2. The influence of paragenetic factors (a farm, production and housing system, season, parity and stage of lactation) on the milk urea content,3. The correlation with milk urea content and parameters of milk yield as well as the somatic cells count,4. The correlation between the milk urea content and the length of open days.This research includes 46,315 samples of milk which were analysed as regular milk recording samples from 11 farms in Vojvodina. There are 10 farms withconventional and only one farm with organic production.Determination of the milk urea contents was carried out by MilkoScan FT+.In the analyzed milk samples the average milk urea content (25.18 mg / dl) was within the optimum values. The coefficient of variation for the milk urea content (34.15%) was significantly higher than the coefficient of variation for the other ingredients in milk.The obtained results in this PhD thesis indicate that the management of a farm has the greatest influence on the content of milk urea. Statistically some significant influence of other examined paragenetic factors was found.According to statistics the housing system significantly influences the milk urea content. Lower milk urea content was found in cow's milk in free-stall system.As the result of specific organic production some statistically significant differences between organic and conventional milk production were found. The differences shows lower milk urea content and milk yield, as well as higher milk fat and protein content. The somatic cells count in organic milk production is significantly lower than their number in milk from conventional milk production. The open days during observation period were longer in cows from an organic dairy farm then the cows from conventional dairy farms.According to season and stage of lactation an important influence on milk urea was found. The seasonal observation shows the lowest milk urea content in autumn period (22.19 mg / dl) and the highest in summer period (27.11 mg / dl). The lowest content was at the beginning of lactation (23.05 mg / dl) and the maximum milk urea content (26.40 mg /dl) was from 121 to 180 days of lactation. Differences in the milk urea content between lactation were small, but statistically significant.There are positive and statistically significant, correlations between the milk urea content and some ingredients of milk, as well as between milk urea content and milk yield. The correlation between the milk urea content and somatic cells count in milk is negative and high statistically significant.It is shown in this research that high milk urea content has negative impact on the length of open days.Obtained results, interpreted in the context of other studies on the same subject indicate the great importance of the observation of the milk urea content. It can contribute to improving the feeding and reproduction on dairy farms, and lead to reduction of both feeding and veterinary costs.

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Venkatapen, Corinne. "Étude des déterminants géographiques et spatialisation des stocks de carbone des sols de la Martinique". Thesis, Antilles-Guyane, 2012. http://www.theses.fr/2012AGUY0513/document.

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Les stocks des éléments dans les sols, et en particulier ceux du carbone, sont en constante évolution sous l’effet de facteurs naturels (climat, végétation, teneurs en argiles, etc.) et anthropiques (usages des sols, etc.). Notre objectif est donc, (i) de mieux comprendre les relations entre type de sol, système de culture et quantité de carbone stockée, (ii) d’étudier les conséquences des changements d’usage et de gestion des terres sur les formes de matière organique dans les sols et (iii) de préciser le rôle de la matière organique sur les propriétés physiques des sols.Des situations agro-pédologiques représentatives des trois grands modèles minéralogiques des sols tropicaux (Sols à allophanes (argiles non cristallisées), Sols à argiles 1/1 et Sols à argiles 2/1) et présentant des systèmes culturaux de différents niveaux d’intensification (monocultures intensives destinées à l’exportation, systèmes paysans faiblement intensifiés, etc.) ont ainsi été sélectionnées sur les sols de Martinique. Par ailleurs, afin de limiter les effets des usages antérieurs des parcelles, nous avons généralement choisi des situations culturales âgées au minimum de 3 ans.L’analyse des stocks de carbone des différentes parcelles fait apparaître des comportements différents : dans les sols à allophanes, il y a un effet de la minéralogie sur la stabilisation des matières organiques ; dans les sols à argiles cristallisées, il existe une corrélation entre la teneur en carbone (ou le stock organique) et la texture (ou teneur en éléments fins), aussi bien pour les situations non cultivées que pour les situations sous cultures. L’amplitude des variations (diminution) des stocks en carbone observées sous l’effet de différents modes de gestion des sols, dépend elle aussi de la texture : dans les sols sableux, la potentialité de séquestration du carbone est faible ou nulle, en revanche, les potentialités de stockage du carbone sont plus fortes dans les sols argileux.L’estimation des stocks totaux de carbone à l’échelle de la Martinique, pour un mètre de profondeur et pour une situation moyenne entre les cartes d’usage des terres de 1969/1970 et 1979/1980, s’élèvent à 11,859 Mt de C calculés pour 95,8% de la surface.La distribution de la matière organique du sol varie avec la texture du sol : dans les sols sableux, à faibles teneurs en matière organique, les matières organiques sont principalement associées aux fractions sableuses ; dans les sols argileux, plus riches en matières organiques, 50 à 60 % de la matière organique sont associées à la fraction argileuse. De même, la dynamique de la matière organique dépend également de la texture du sol : dans les sols sableux, les variations des stocks organiques sont essentiellement dues à la perte ou à l’accumulation en carbone de la fraction sableuse ; dans les sols argileux, la fraction argileuse participe de manière prépondérante aux variations des stocks organiques de ces sols lors de leur mise en culture ou en prairie ; les sols sablo-argileux ont un comportement intermédiaire entre ces deux pôles.La stabilité structurale varie avec la minéralogie. Les andosols (ou ALL) présentent un haut degré d’agrégation et de stabilité, du à la présence d’allophanes et à leur association particulière avec les composés organiques. Dans les sols à argiles cristallisées, la stabilité de l’agrégation est plus élevée dans les sols à argiles 1/1 (ou LAC) ; les valeurs les plus faibles sont généralement observées dans les parcelles sur sols à argiles 2/1 (ou HAC). En outre, la mise en culture se traduit généralement par une diminution de la stabilité de l’agrégation.L’intensification des cultures (labours fréquents, faibles restitutions de matière organique au sol, etc.) accentue la perte de la stabilité de l’agrégation provoquée par la mise en culture, en particulier dans les parcelles sur sols à argiles 2/1 (ou HAC)
Soils elements stocks, and particularly those of carbon, are in constant evolution under natural factors effect (climate, vegetation, clays content, etc) and anthropic factors effect (soils uses, etc). Our objective is thus, (i) to better understand the relations between soil, farming system and stored carbon quantity, (ii) to study the consequences of soils uses changes and of soils managements changes on organic matter shapes in soil and (iii) to specify organic matter role on soil properties physics.Representative agri-pedological situations of the three great mineralogical models of tropical soils (allophonic soils (not crystallized clays), 1:1 clay soils and 2:1 clay soils) and presenting agricultural systems of various levels of intensification (intensive monocultures intended for export, slightly intensified farming systems, etc) were thus selected in the soils of Martinique. In addition, to limit the effects of their former uses, we generally chose to the minimum 3 years old farming situations.The analysis of the various lands carbon stocks reveals different behaviors: in allophonic soils, a correlation exists between carbon content (or organic stock) and texture (or fine elements content), as well for not cultivated as for cultivated situations. Variations ranges (reduction) of carbon stocks observed under various management soils systems effect, also depends on texture: in sandy soils, carbon sequestration potentiality is low or null, on the other hand, carbon storage potentialities are higher in clay soils.The estimation of total carbon stocks on the scale of Martinique, for one meter of depth and for and average situation between the use soils charts of 1969/70 and 1979/80, rises to 11,859 Mt of C calculated for 95,8% of the surface.Soil organic matter distribution varies with soil texture: in sandy soils, with low contents of organic matter, organics matters are mainly associated with the sandy fractions; in clay soils, richer in organic matters, 50 to 60% of the organic matters are associated with the argillaceous fraction. In the same way, the organic matter dynamics also depends on soil texture: in sandy soils, organic stocks variations are primarily due to carbon loss or accumulation of the sandy fraction; in clay soils, the argillaceous fraction takes part in a dominating way in organic stocks variations of these soils at the time of their setting in culture or meadow; the sand-clay soils have an intermediate behavior between these two poles.Structural stability varies with mineralogy. Andosols (or ALL) present a high degree of aggregation and stability, due to the presence of allophones and their particular association with the organics compounds. In crystallized clay soils, aggregation stability is higher in 1:1 clay soils (or LAC); the lowest values are generally observed in the lands on 2:1 clay soils (or HAC). Moreover, culture setting generally results in aggregation stability reduction.Cultures intensification (frequent ploughings, low organic matter restitutions to the soil, etc) accentuates aggregation stability loss caused by culture setting, particularly in lands on 2:1 clay soils (or HAC)

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Achuo, George. "Partner satisfaction and renewal likelihood in consumer supported agriculture (CSA) : a case study of The Equiterre CSA network". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19555.

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"Isolation, identification, and antimicrobial susceptibility analysis of Enterococccus spp. and Salmonella spp. from conventional poultry farms transitioning to organic farming practices". UNIVERSITY OF MARYLAND, COLLEGE PARK, 2009. http://pqdtopen.proquest.com/#viewpdf?dispub=1465544.

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Sung, Wan-Lin, e 宋宛霖. "Studies on the soil quality with organic and convention farming systems affected under different fertilization practices". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/55455596388581782793.

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碩士
國立中興大學
土壤環境科學系所
95
How to guarantee the positive effect of the addition of organic fertilizer and reduce the negative effect on the gualities of the crop and the environment is the urgent matter. The objectives of this research was to study on the soil qualities affected by the fertilization practices under organic and convention farming systems. Laboratory incubation and field expriments were conduted in this study. Incubation experiment was to determine the nitrogen and phosphorus release characteristic of composeted animal manure and soybean meal in Liuying soil, while the farm experiment was conducted in the organic and convention farm in the Asia vegetable Research and Development Center with mini-cabbage and cherry tomatoes rotation. Six fertilizer treatments, including Ⅰ(traditional estimation), Ⅱ(N releasing estimation), Ⅲ(P releasing estimation), Ⅳ(high efficiency estimation), Ⅴ(balanced estimation), and Ⅵ(nutrient uptake matched estimation) with Randomized complete block design (RCBD) and 4 replicates. Results of laboratory incubation experiment showed that the N and P release rate of soybean meal applied in Liuying soil after 100 days were 38 % and 64 % respectively. The Prelease rate of the composeted animal manure applied in Liuying soil was of the 61 % , whereas soil inorganic N content was lower than that of control reason needs be studies in the furthure. Different treatments under the organic and convention farming system all increased the inorganic N, Olsen-P, exchangeable Ca and Mg contents and reduced the bulk density and penetration resistance of the soil, and the most significant effect was found in the treatment of N releasing estimation. The soil heavy metal content and nutrient accumulation of the treatment IV (high efficiency estimation) and treatment VI (nutrient uptake matched estimation), after two crops, were lower other treatments, and the total fertilizer tapplied in the treatment VI (nutrient uptake matched estimation) was lower than that treatment IV (high efficiency estimation). The treaments of IV (high efficiency estimation), V (balanced estimation) and VI (nutrient uptake matched estimation) used less amount of fertilizers, showed had a higher yeild of crops. Based on the evaluation by soil nutrient availability, the status of nutrient accumulation, and the crops growth, the treatment IV (high efficiency estimation) and VI (nutrient uptake matched estimation) are the better fertilizing practice, not only may guarantee higher in the soil quality the crops production, and have higher efficiency of fertilization.

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46

Sousa, Filipe da Silva Pinto de. "Multidimensional approach of Organic and Conventional Farming: A Systematic Review". Dissertação, 2020. https://hdl.handle.net/10216/132139.

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47

Sousa, Filipe da Silva Pinto de. "Multidimensional approach of Organic and Conventional Farming: A Systematic Review". Master's thesis, 2020. https://hdl.handle.net/10216/132139.

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48

Dhladhla, Daniel T., e 德席尼. "Why do Taiwanese Farmers Adopt Organic Farming Practices? Observations Based on Organic Farmers Markets". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/65768601247180909109.

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Abstract (sommario):

碩士
國立屏東科技大學
熱帶農業暨國際合作系
101
Student ID: M10022039 Title of thesis: Why do Taiwanese Farmers Adopt Organic Farming Practices? Observations Based on Organic Farmers markets Total page: 116 Name of Department: Department of Tropical Agriculture and International Cooperation Graduate date: May 27, 2013 Degree conferred: Master Name of Student: Daniel Luthini Dhladhla Advisor: Huang Wen-Chi, Ph.D. The Content of Abstract in This Thesis: Organic farming is one of the leading sustainable farming initiatives which are friendly to the environment and it enhances food safety by promoting the ethical use and care of resources. Over the past twenty years, Taiwan government has shown support of organic agriculture. When the organic regulation was initiated in 2003 it had accredited 3 certification bodies, and in 2013 there are 13 certification bodies in Taiwan. The adoption of organic farming practices in Taiwan is currently low as less than four percent of the total agriculture land is certified organic. This study seeks to find out the reasons that influence the adoption of organic farming using qualitative data analysis to determine those factors which influence producers to adopt organic farming. In depth interviews at organic farmers markets in Taichung City, Kaohsiung City, and Pingtung County was carried out with certified organic producers (with 35, 30, and 25 participants, respectively) discussions to determine what influences the producers to convert fully to organic farming. The results show that ease of access to planting material, access to information, organic certification bodies, and the government policy have a positive influence on the adoption of this technology. Most farmers in Taiwan are not motivated by the premium price but by environmental, producer and consumer health in adoption of organic farming. The share of land committed to organic was also constrained by the difficulty to produce parallel products on the small land holdings and higher cost of establishing netting facilities on the farms. The major constraints to the certified organic farming in Taiwan are extension services, and the marketing infrastructure that is not very well developed and coordinated for the organic products which need a differentiated channel from the conventional products. Improving marketing infrastructure for organic products in Taiwan will have positive effects on the adoption of organic farming practices in Taiwan.

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49

Yu-ChiehPiao e 標雨倢. "Correlation analysis on the responses of soil microbial community to organic and conventional farming". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/28967936835220697508.

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碩士
國立成功大學
生物多樣性研究所
100
Differences in soil physicochemical properties, microbial physiological variables and community structure were investigated in organic and conventional agroecosystems located in Nantou County, central Taiwan. Two series of soil samples from below the tea shrub canopy (TI) and between teas shrubs (TII) were collected monthly during 2011 from each study site. Physicochemical and physiological parameters were analyzed using a two-way ANOVA to determine the impact of farming type and sampling position. Assessment of the relationships between those parameters was performed using the Pearson correlation. The microbial community structure and functional diversity were established based on substrate induced respiration (SIR), which indicates the metabolic potential of the microbial community. Farming type, sampling position and their interaction had a significant impact on physicochemical and physiological variables, whereas functional diversity was not affected by sample position and microbial biomass by their interaction. The results of physiological parameters indicate that organic farming could reduce the metabolic quotient (qCO2) and basal respiration and increase the functional diversity and catabolic ability of the microbial community, especially with amino acids and carbohydrates.

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50

Pinho, Alyssa Oliveira. "Chemical contamination of organic products versus conventional products". Master's thesis, 2019. http://hdl.handle.net/10400.14/30593.

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The objective of this thesis was to delve into a sector of food safety which is lacking research, chemical contamination of organic foods. In regards to studies that have been conducted on organic products, a majority of the research has focused on the biological contamination of organic foods verses conventional products. A systematic review was conducted using the databases Academic Search Premier and PubMed to gather peer reviewed publications. Also, regulations were referenced to determine if chemical contaminants are being adequately controlled in both organic and conventional products. The results indicated that there are various factors that can lead to the chemical contamination of crops despite their mode of production. Such factors include: exposure of pollutants through the air, contaminated water, soil, food fraud, and packaging materials. A significant difference, however, between organic and conventional products is that pesticides are restricted in organic agriculture. Therefore, these products contain less pesticide vestiges. The results also demonstrated that globally, there are strict regulations to effectively control pesticide exposure. EFSA found that in the European Union 96.2% of crops complied with legal standards and in the United States, the USDA found that 99.5% fulfilled legal standards. Thus, this diminishes a key argument that organic products are superior on the premise that they contain inferior amounts of pesticides because the contamination of pesticides in conventional foods is not a significant danger to begin with.
Esta tese tem por objetivo investigar um setor da segurança alimentar menos investigado, a contaminação química dos alimentos orgânicos para determinar se são superiores no que duz respeito a segurança. Foi realizada uma revisão sistemática usando as bases de dados Academic Search Premier e PubMed. Os resultados demonstram que existem vários fatores que levam à contaminação química dos alimentos, muitos quais o método de produção não pode controlar. Tais como os poluentes no ar, fontes de água contaminadas e metais naturalmente no solo. Também, químicos contidos nas embalagens podem migrar para os produtos alimentícios. Apesar de existir estudos que implicam que os alimentos orgânicos têm benefícios de saúde superiores comparados com os convencionais, os consumidores que optam pela compra de produtos orgânicos têm a tendência de se preocupar mais com a saúde e consequentemente se empenham em atividades de promoção da saúde. Uma diferença significativa, no entanto, entre produtos orgânicos e convencionais é que os pesticidas são restritos na agricultura orgânica. Por isso, esses produtos contêm menos vestígios de pesticidas. Os resultados também demonstram que, globalmente, existem regulamentos rigorosos para controlar efetivamente a exposição aos pesticidas. A EFSA constatou que na União Européia 96,2% das lavouras cumpriam as normas legais e a USDA nos Estados Unidos concluiu que 99,5% cumpriram os padrões legais. De acordo com os resultos desta revisão, produtos orgânicos não são superiores em relação à contaminação química.

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