Дисертації: "Agricultural Production Systems Simulator"

1

Rabie, Pierre-Andre. "A simulation model for evaluating the long-term financial impact of different wine grape production systems." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96864.

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ENGLISH ABSTRACT: Agricultural production takes place in an uncertain and complex environment, with production the result of the culmination of a variety of factors within a greater system. Consequently, accounting for the influence of variables in the production system is very difficult, making it a daunting task for decision makers to make good decisions. In the wine grape production context, this problem is accentuated due to the capital intensive and perennial nature of investments, also giving rise to a path dependency. As a result it is essential to make strategically sound decisions in order to ensure the long-term profitability and financial feasibility of wine grape production. Decision making tools, like a model, can be of invaluable support for strategic decision making. A model is used to simplify reality, by imitating and simulating the actual system as closely as possible. A simulation model was therefore developed for this thesis to be able to evaluate the long-term financial impact of different wine grape production systems and to support strategic decision making. This model can be adapted to individual farm specific features, scenarios and preferences, in the evaluation and analysis of different investment and wine grape production system decisions. For this study, the nature of agricultural systems as well as qualities required by a simulation model, were investigated. The former is followed by an investigation of the effect of the grapevine and trellis specific qualities on the possibilities of the production system, as well as the implication of capital budgeting and financing considerations on the performance of the wine grape production system. In view of the above, the model was then applied to simulate and evaluate different wine grape production systems as well as a structural transition and expansion of wine grape production, for a simulated farm in the Breedekloof region, South Africa. The model can be used for decision making and scenario planning purposes by wine grape producers and stakeholders in the wine industry.
AFRIKAANSE OPSOMMING: Landbouproduksie vind plaas in ‘n komplekse omgewing met talle onsekerhede, waar produksie die resultaat is van ‘n aantal faktore binne ‘n groter geheel. Die uitdaging is dus om die spesifieke invloed van veranderlikes binne die produksiestelsel waar te neem sodat besluitnemers ingeligte besluite op grond daarvan kan maak. In die verbouing van langtermyn gewasse, spesifiek die van wyndruif verbouing, word hierdie probleem beklemtoon vanweë die kapitaal intensiewe en meerjarige aard van investerings, wat aanleiding gee tot die afhanklikheid van vorige besluite. Ten einde die langtermyn winsgewendheid en lewensvatbaarheid van wyndruif produksie te verseker, is strategiese en ingeligte besluite deurslaggewend. Hulpmiddels in die besluitnemingsproses, soos modelle, kan onskatbare ondersteuning bied in hierdie konteks. Die doel van ‘n model is om ‘n werklike stelsel te weerspieël, maar terselfdertyd word vereenvoudigende aannames gemaak. Vir die doeleindes van hierdie tesis is ‘n simulasie model ontwikkel om die langtermyn finansiële impak van verskillende wyndruif produksiestelsels te weerspieël en strategiese besluitneming te bevorder. Hierdie model kan aangepas word vir die individuele vereistes, voorkeure en kenmerke van individuele plase, ten einde verskillende investeringsbesluite en wyndruifproduksiestelsels te evalueer. Vir die doeleindes van hierdie studie is die aard van die stelsel waarin landbouproduksie plaasvind, asook eienskappe wat benodig word deur ‘n simulasiemodel, om ‘n goeie weerspieëling van die werklikheid te kan gee ondersoek. Daarna is die invloed van die prieëlstelsel oorweging op die wingerdstok, die uitvoerbaarheid van verskillende bewerkingspraktyke, asook die invloed van kapitaal- en finansiëringsoorwegings op die prestasie van die wyndruifproduksiestelsel ondersoek. In die lig van bogenoemde oorwegings is die model gebruik om verskillende wyndruifproduksiestelsels te simuleer en te evalueer, asook om ‘n strukturele oorgang en uitbreiding vir ‘n plaas in die Breedekloofstreek in Suid-Afrika te ondersoek. Wyndruif produsente en belanghebbendes in die wynbedryf kan hierdie model in scenario beplanning en besluitneming gebruik.

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2

Prayitno, Shafiq. "Analysis of crop-machinery systems for wetland rice production." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386712.

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3

Mallory, Ellen B. "Crop/Livestock Integration Effects on Soil Quality, Crop Production, and Soil Nitrogen Dynamics." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/MalloryEB2007.pdf.

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4

Keerthipala, Adhikari Pathiranage. "Sustainability of small-holder sugarcane-based production systems in Sri Lanka." Thesis, University of Aberdeen, 1997. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU093678.

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This study analyses important technical, managerial and economic factors in relation to the long-run sustainability of the small-holder sugarcane-based production systems at the three main sugar mill areas in Sri Lanka. The sustainability is an issue in view of the low overall productivity and profitability of the Sri Lankan sugar industry, the absence of grower-miller and grower-grower equity, and environmental concerns over sugarcane cultivation and processing. The degree of sustainability was measured by a composite index involving the economic welfare of farm households, the viability of the sugar companies, grower-miller equity, and the fertility status of sugarcane-growing soils. The analysis was carried out by means of a dynamic and stochastic simulation model of small-holder sugarcane production, and sugar and molasses processing. The model consists of production and processing sub-models, together with subsidiary sub-models for cane and ex-factory sugar pricing, rice production and off-farm activities. It uses primary data from a farmer survey, and secondary data from sugar companies, sugarcane experiments and other sources. The results indicate that productivity of sugarcane farming and sugar processing is mainly affected by technical/management factors, and profitability by both technical/management and economic factors. The existing cane payment systems are not equitable in dividing the proceeds of sugar and by-product processing. An alternative formula, which takes into account the commercial value of cane, and divides sugar proceeds in proportion to cost shares and by-product proceeds on an agreed proportion, ensures greater grower-miller equity. In most situations, sugarcane cultivation does not degrade N fertility of soils, but it depletes P and K. Overall, the level of sustainability is low for both settler and out-grower systems under the existing conditions at Hingurana and average for Pelwatte and the irrigated system at Sevanagala. For the rain-fed system at Sevanagala, it is above average.

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5

Holliman, James Bret Adrian John. "An economic analysis of integrating hydroponic tomato production into an indoor recirculating aquacultural production system." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/HOLLIMAN_JAMES_4.pdf.

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6

Gulbenkian, Marcos. "The potentials for improvement of traditional sheep cheese production systems in Portugal." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333431.

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7

Ortiz, Oblitas Oscar Ernesto. "The information system for IPM in subsistance potato production in Peru." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388581.

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8

Lowman, James Scott. "Utilizing Beneficial Bacterial Endophytes to Promote Switchgrass Growth in Low- input Agricultural Production Systems." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56480.

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The US Department of Energy has focused research efforts on developing switchgrass into a bioenergy feedstock, helping to offset the use of non-renewable fossil fuels and make the US more energy independent. Bacterial endophytes, which reside inside plant tissues, are proven to increase yield and stress resistance in a number of plants. The primary objective of this dissertation was to explore the use of endophytes to improve biomass yields of switchgrass on lands not suitable for food crops and better understand the underlying mechanisms of the plant-endophyte interaction. Integration of this research into K-12 STEM education to increase interest in plant sciences and create the next generation of scientists with the motivation to help solve the challenges facing society in the twenty first century was the objective of the outreach component of this project. Chapter one demonstrates the ability of Burkholderia phytofirmans strain PsJN to colonize switchgrass and promote plant growth under in vitro (approximately 50% higher), and growth chamber and greenhouse (48.6% higher biomass yields) conditions. The objectives of Chapter two were to determine stand establishment in the field with different nutrient levels. PsJN bacterization positively benefited growth and development of switchgrass seedlings in the field with both low and high nutrient content. Highly significant (p<0.001) stimulation of root and shoot growth, lateral root formation and number of tillers was recorded on soil with low fertility. PsJN bacterization also enhanced biomass accumulation during the two seasons of growth on both poor (p<0.001) and rich (p<0.05) soil, indicating the potential for the use of PsJN in a low-input switchgrass feedstock production system. Chapter three outlines differences in gene expression patterns upon bacterization, between the responsive cv. Alamo, and a non-responsive cv. Cave-in-Rock. Using EST microarrays and quantitative PCR up- and down-regulated genes were identified in both cultivars. One of the key genes identified was a member of the tau class, glutathione S-transferase (GST). GST enzymes are known to be involved in plants responses to stress. Using overexpression and knockout/knockdown techniques we demonstrated that GST is likely involved in the bacterization induced early plant growth promotion in switchgrass. Chapter four describes the potential for the utilization of beneficial bacterial endophytes capable of fixing atmospheric nitrogen in a free-living state in the development of low-input switchgrass feedstock production systems. Sphingomonas sp. strain NSL isolated from switchgrass tissue was able to grow on nitrogen free medium and stimulated growth of switchgrass cv. Alamo under nitrogen deficient conditions. The ability to fix atmospheric nitrogen was also moved to Burkholderia phytofirmans strain PsJN via horizontal gene transfer from the legume nodulating Burkholderia phymatum. The transformed PsJN was able to fix nitrogen and promote plant growth under nitrogen limited conditions. At every step of the research described in this dissertation efforts were made to include its elements into K-12 education. Chapter five describes four case studies aiming at the enhancement of youth interest in plant sciences in the socieoeconomically depressed areas of Southside Virginia.
Ph. D.

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9

Dammur, Manoj. "Stimulating national biogas production : The case of Swedish agricultural wastemanagement." Thesis, Linköpings universitet, Industriell miljöteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-172019.

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Swedish state has been promoting alternative renewable fuels like biogas to reduce the dependency on fossil fuels and to curb related greenhouse gas emissions. Owing to many policies like subsidies and tax exemptions for using biogas, the country has seen a surge in demand for biogas. Meanwhile, the increase in production of biogas in Sweden has been modest in recent years, though many studies have estimated substantially higher potentials from many sources. Agricultural feedstock/biomass is one among these sources where production and use of biogas could address many challenges faced by farmers like agricultural waste management, soil nutrient management, methane emissions from manure etc. while closing the nutrient cycle and contributing to sustainability.This work is an investigation on how to stimulate the growth of biogas production based on agricultural feedstock/biomass production in Sweden. Since policies give different results in different states/countries depending on the local preconditions, locally developed policies, national policies and EU policies should integrate well in all the policy sectors in that particular region to give the intended result. The current production capacity is about 2 TWh worth of biogas/year but the theoretical potential is estimated to be up to 15 TWh that has been claimed by many researches and literature works like in (Westlund, et al., 2019). Much of the potential has not been explored especially in the field of agriculture. It is asserted in many articles that the true potential of biogas production from Swedish agriculture is far greater than what is produced today. Yet, all the regulations, financial and other financial instruments failed to stimulate local biogas production in Sweden to attain its full theoretical potential. The results presented in this study show where these policies failed and what else apart from the policies could be improved in order promote biogas production.Farmers are hesitant to invest in biogas production because of the complexity and unpredictability of the existing policies. There has been significant negative impact from lack technological training of anaerobic digestion (AD) technology. This is also reflected as difficulties in finding trained and dedicated staff for biogas plant operations. Low profitability of biogas business exists ever since the production started and the financial aids are insufficient. Strict digestate regulations along with worsening substrate competition also creates problems. Permits to run the biogas plants are perceived to be expensive alongside increasing investment costs and taxes, affecting already low profitability. There is also a lack of infrastructure in terms of electricity/gas grid connectivity. Feed in tariffs for electricity produced from renewable sources are not bringing enough profitability to the business. Technological improvements are needed in terms of agricultural machinery that can use upgraded biogas as fuel and treatment of digestate to eliminate heavy metal content. Producers need more long term, sure market for their biogas.
Biogasmarknadsutredningen of BRC

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Sleeper, Adam Maxey Sibley Jeffrey Lynn Chappell Jesse Alan. "Integration of intensive aquaculture and horticulture crop production." Auburn, Ala., 2009. http://hdl.handle.net/10415/1953.

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11

Negatu, Workneh. "Cereal-based farming systems in the central highlands of Ethiopia : technological innovation for surplus production and poverty alleviation." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337981.

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12

Beyene, Abera Hailu. "Adoption of improved tef and wheat production technologies in a crop-livestock mixed systems in northern and western Shewa zones of Ethiopia." Pretoria : [S.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-06092008-133248/.

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13

Saraswat, Dharmendra. "Geospatial technology applications to strawberry, grape and citrus production systems." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1174533489.

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14

Allison, John T. Jr. "TWO ESSAYS ON INPUT SUBSTITUTION AND OPTIMAL DECISION MAKING IN CROP AND LIVESTOCK PRODUCTION SYSTEMS." UKnowledge, 2019. https://uknowledge.uky.edu/agecon_etds/80.

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The thesis presented consists of two essays that analyze input substitution and decision making in crop and livestock production systems. The first essay consists of a whole-farm analysis that sought to optimize feed mixes and enterprise combinations for an organic dairy operation in the Southeastern United States. This was accomplished through mathematical programming where whole-farm net returns were maximized, and total feed costs were minimized simultaneously for four milk production level cases. Additionally, the sensitivity of the system and break-even milk price were explored. Results suggest substitutability in ration components where an increase in supplemental feeds is justified by additional milk output and sales. The second essay utilizes econometric methods and hedonic modeling to explore factors that drive the price of row crop planters on the used machinery market. Factors relating to make, age, condition, planter specifications, sale type, spatial aspects, seasonality, and year of the sale were analyzed. Results suggest non-linear relationships for row number and age relative to price and interactions between variables make and age that imply varying depreciation depending on the manufacturer. An additional break-even analysis relating to pasture yields and planter purchase price was conducted to explore these primary concepts in further detail.

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15

Mangold, Anja [Verfasser], and Iris [Akademischer Betreuer] Lewandowski. "How can miscanthus be integrated most efficiently into agricultural production systems? / Anja Mangold ; Betreuer: Iris Lewandowski." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2020. http://d-nb.info/1203206585/34.

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16

Van, Hoving Susanna Catharina Petronella. "An evaluation of different extensive wildlife production systems in the Western Cape Province of South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6551.

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Thesis (MScAgric (Agricultural Economics))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The wildlife industry in the Western Cape Province is growing, but lacks, particularly, economic research. This study explores the manner in which wildlife production systems in the Western Cape are currently operated and describes the characteristics of this industry. Furthermore, results on the evaluation of identified typical wildlife production systems in different regions of the Western Cape are revealed together with critical factors influencing success. No confusion remains regarding the importance of this industry. Wildlife production units cover a noteworthy percentage of the total area and are evenly spread within the province. The industry grew rapidly in the past 10 years and with a high diversity of at least 37 different wildlife species; ecotourism, hunting and live sales are the most prominent ways of utilising wildlife. This industry also contributes in terms of job opportunities supplied. The two typical systems evaluated are the biltong hunting system in the Beaufort West region and the trophy hunting system in the Southern Cape region. The biltong hunting system has been shown to be profitable, though it realises skimpy profits. It is, however, successful by virtue of the fact that wildlife producers perceive the wildlife enterprise as additional income to livestock production, almost without any additional costs. Although the gross margin per large stock unit is high, the trophy hunting system is not profitable and runs at a loss. The main problem is the overhead costs that exceed the gross margin, due to too low a number of wildlife species marketed. The industry in this region is, according to wildlife producers, hampered by legislation and regulations, which limit the variety of species allowed in the region. These wildlife producers manage their system on a part-time basis and fund it from other income sources. The Department of Agriculture is urged to assist the wildlife industry in the form of research on the economic, ecological and social impacts of this industry to determine its full contribution and capacity. Although wildlife producers contribute towards conservation and the application of sound conservation principles is important to them, they need to generate an income from wildlife production in order to make a living out of it, which ultimately makes it worth their while. Despite the systemic problems of a number of wildlife production systems, some wildlife producers are of the opinion that the pressure experienced in terms of legislation, makes it harder for them (in some regions more than other) to manage their wildlife production units in a profitable manner. Although the main objectives of government conservation authorities and wildlife producers might differ, the contribution of both towards conservation serves as common ground. It is therefore suggested that a joint approach is followed between government conservation authorities, the Department of Agriculture and wildlife producers to further develop the wildlife industry.
AFRIKAANSE OPSOMMING: Die wildbedryf in die Wes-Kaap groei tans, maar het ‘n tekort aan, veral, ekonomiese navorsing. Hierdie studie ondersoek die manier waarop wildproduksiestelsels tans in die Wes-Kaap Provinsie bedryf word en beskryf die karaktereienskappe van hierdie bedryf. Verder word die resultate van die evaluasie van die geïdentifiseerde tipiese wildproduksiestelsels in verskillende areas van die Wes-Kaap Provinsie bekend gemaak, tesame met die kritiese faktore wat sukses beïnvloed. Daar is geen twyfel oor die belangrikheid van hierdie bedryf nie. Wildplase beslaan ‘n betekenisvolle persentasie van die totale oppervlakte en is eweredig versprei in die provinsie. Die bedryf het vinnig gegroei in die laaste tien jaar en met ‘n groot verskeidenheid van minstens 37 verskillende wildspesies, is eko-toerisme, jag en lewende verkope die mees algemene manier om wild aan te wend. Die bedryf dra ook baie by in terme van werksgeleenthede. Die twee tipiese wildproduksiestelsels wat geëvalueer is, is die tipiese biltongjagstelsel in die Beaufort-Wes omgewing en die tipiese trofeejagstelsel in die Suid-Kaap omgewing. Die biltongjagstelsel toon winsgewend te wees, al is dit karige winste wat realiseer. Dit is egter suksesvol in die sin dat wildboere die wildvertakking sien as ‘n addisionele inkomste tot die lewendehawe produksie, amper sonder enige addisionele kostes. Alhoewel die bruto marge per grootvee-eenheid goed lyk, is die trofeejagstelsel nie winsgewend nie en maak ‘n verlies. Die eintlike probleem is die oorhoofse koste wat meer is as die bruto marge, as gevolg van te min en te klein verskeidenheid wild wat bemark word. Die bedryf in hierdie omgewing, na die mening van wildboere, word terug gehou deur wetgewing en maatreëls, wat die verskeidenheid wildspesies wat toegelaat word in die omgewing beperk. Hierdie wildboere bestuur hul stelsels op ‘n deeltydse basis en befonds dit vanuit ander inkomste bronne. Die Departement van Landbou word aangeraai om die wildbedryf by te staan in die vorm van navorsing op die ekonomiese, ekologiese en sosiale vlakke van die wildbedryf om sodoende die volle bydrae en omvang van hierdie bedryf te bepaal. Alhoewel wildboere bydra tot bewaring en die toepassing van suiwer bewaringsbeginsels vir hulle belangrik is, het hulle nodig om ‘n inkomste te genereer uit wildproduksie om sodoende ‘n bestaan daaruit te kan maak. Buiten die sistemiese probleme wat ondervind word by sommige wildproduksiestelsels, is party wildboere van mening dat die druk wat ervaar word in terme van wetgewing en maatreëls, dit vir hulle moeiliker maak om hul wildplase op ‘n winsgewende manier te bestuur. Alhoewel die doelwitte van die natuurbewaringsgesag en wildboere van mekaar mag verskil, dien die bydrae tot bewaring deur albei partye as gemeenskaplike grond. Om daardie rede word dit aanbeveel dat ‘n gesamentlike benadering tussen die regering se natuurbewaringsgesag, die Departement van Landbou en die wildboere gevolg word, om die wildbedryf verder te ontwikkel.

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17

Laird, Megan K. "Surface and groundwater quality impacts of conservation tillage practices on burley tobacco production systems in Southwest Virginia." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9728.

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This study measured sediment, nutrient and pesticide edge-of-field and deep percolation losses from conventional tillage (CT), strip tillage (ST), and no-till (NT) treatments in a burley tobacco production system. The field experiment results show that the CT treatment yielded more total runoff, 93.6 mm, than ST and NT. Compared to the CT treatment, ST reduced the total mass loss of NO₃⁻ by 37 percent, NH₃ by 54 percent, PO₄³⁻ by 12 percent, TP by 65 percent and TSS by 64 percent. The NT treatment reduced the total mass of NO₃⁻ by 49 percent, NH₃ by 46 percent, PO₄³⁻ by 17 percent, TP by 73 percent and TSS by 77 percent. Field experiment results showed that, respectively, the ST and NT treatments yielded 77 and 82 percent less chlorpyrifos, an insecticide, mass loss in runoff compared to CT. With respect to flumetralin loss, a growth inhibitor, the NT treatment yielded 30 percent less and ST yielded 6.8 percent more flumetralin mass, compared to CT. The percolated water results show that compared to the CT treatment, ST resulted in 33 percent less NH₃, 7.5 percent less TKN, and 39 percent less PO₄³⁻ total mass. The NT treatment yielded 41 percent less NH₃ and 20 percent less TKN total mass loss compared to the CT treatment. The NT treatment had the most NO₃⁻, PO₄³⁻, and TP mass loss below the root zone, however NT also had the most percolated water by 53 mm (838 L). The ST treatment yielded 77 percent less, and NT yielded 82 percent less chlorpyrifos mass loss compared to the CT treatment. Compared to CT, the NT treatment resulted in 30 percent less and ST yielded 7 percent more flumetralin mass in percolated water. The GLEAMS model was used to simulate runoff, nutrient, sediment and pesticide losses from the same three tillage practices evaluated in the field experiment. The model results showed that for runoff volume, TSS, nitrogen, chlorpyrifos and flumetralin in runoff, the conventional tillage practice generated greater losses than the conservation tillage practices. Compared to the field experiment results, GLEAMS under predicted nitrogen and phosphorus in percolated water. The conservation tillage practices simulated in GLEAMS were effective in minimizing the loss of agricultural pollutants.
Master of Science

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18

Papendiek, Franka [Verfasser], and Hubert [Akademischer Betreuer] Wiggering. "Fodder legumes for Green Biorefineries : a perspective for sustainable agricultural production systems / Franka Papendiek ; Betreuer: Hubert Wiggering." Potsdam : Universität Potsdam, 2015. http://d-nb.info/1219077437/34.

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19

Burgoa, Chopitea Marco Antonio Domingo. "Analysis and organization of the family based agricultural production system in the Poroma community of Oropeza province." BYU ScholarsArchive, 2000. https://scholarsarchive.byu.edu/etd/5335.

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This research analyzed the management strategies and organization of crop production in a family agricultural system. This study took place in the Poroma community, Oropeza province, Chuquisaca Department, in Bolivia, at the so called “red zone”, so named for its extreme poverty. The agricultural system used in this study is unique to the pre-puna area of Bolivia and is located in a meso-thermal valley with wet summers. This agricultural system uses a diverse number of native and cultivated plants and animals and incorporates interrelated production strategies in agriculture, animal husbandry, forestry, and crafts. Two important production sectors have been identified in the community: sunny and shady. The four main crops in these sectors are potato, corn, wheat, and barley, with an additional 35 complementary crops. Additionally, 78 crops were identified with specific agronomic and nutritious characteristics. These crops included two used for candy; 56 for human health, and 36 for firewood, wood, dye, and tanning procedures. Limitations with this agricultural system are weak community structural organization, the presence of pests and diseases in crops, and the lack of traditional cultivation practices.

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20

Claasen, Claasen. "The effect of agricultural production system on the meat quality of Dorper lambs." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/19896.

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Анотація:

Thesis (MScAgric)--Stellenbosch University, 2008.
ENGLISH ABSTRACT: The aim of this study was to investigate the effect of South African production system (feedlot {FL-} or free-range {FR-}) and gender (ewes, rams or castrates) on growth and carcass characteristics of Dorper sheep. Male lambs (castrates and rams) grew twice as fast as ewes (P<0.05) under FL-conditions while much smaller differences were observed between gender groups in FR-lambs. FL-lambs produced heavier carcasses (P=0.0003) with higher dressing percentages (P<0.05) and greater carcass fatness levels (P<0.052) than FR- lambs. No differences attributable to production system were found on meat tenderness (as indicated by Warner Bratzler shear force strength) and on the intramuscular lipid concentration. In contrast, sensory evaluation results suggested that meat from FL-lambs was juicier and more tender than meat from FR-lambs. The sensory panel could not distinguish between FL and FR meat as far as the attributes of aroma and flavour were concerned. Cholesterol results indicated that for intermuscular fat, higher cholesterol levels were observed for FL-lambs than for FR-lambs. The level of palmitic acid (C16:0) was significantly higher (P=0.0375) in the Longissimus dorsi (LD) muscles of FL-lambs. For intramuscular fat from the Biceps femoris (BF) muscle, g-linolenic acid (C18:3n-6) was higher (P<0.0001) in FL- lambs. Results for intramuscular BF further indicated that ram lambs had the highest (P=0.0019) palmitic acid (C16:0) and sum of TUFA (P=0.0014), castrates had the highest (P=0.0260) α-linolenic acid (C18:3n-3) and g-linolenic acid (C18:3n-6), while ewe lambs had the highest (P=0.0014) SFA concentrations. Linoleic acid (C18:2n-6c) was significantly higher (P=0.0067) in the subcutaneous fat of FL-lambs while FR-lambs had more linolenic acid (C18:3n-3). For the kidney fat, FR-feeding increased (P < 0.05) stearic (C18:0), linolelaidic (C18:2n-6t), α-linolenic (C18:3n-3) and homo-g-linolenic acid (C20:3n-6) percentages. Conversely, linoleic acid (C18:2n-6c) was increased (P=0.0372) by FL-feeding. For the intermuscular fat, FR-lambs had higher linolenic acid (C18:3n-3) and SFA (P=0.0113 and P=0.0341) compared to FL-lambs. On the other hand, the sum of TUFA for the intermuscular fat was higher (P=0.0341) in FL-lambs compared to FR-lambs. Results from the study imply that the consumer may not necessarily be able to discern between meat from FR- or FL-lambs, although they may possibly discriminate against the increase in visible fatness of FL-lambs. No clear advantage of production system in terms of human health could be demonstrated as far as the proximate chemical composition and the fatty acid composition of the meat was concerned. The faster growth and the associated shorter production cycle of FL-lambs could be an advantage under certain production systems. However, it needs to be weighed against the cost of concentrate feeding and the preference consumers are likely to develop for lamb produced in natural environments.
AFRIKAANSE OPSOMMING: Die doel van die studie was om Suid Afrikaanse produksiestelsel (voerkraal {VK-} of veld {VD}) en geslag (ooie, hamels of ramme) op die groeivermoë en karkaseienskappe van die Dorperskape te bepaal. Manlike lammers (ramme and hamels) het twee keer vinniger (P<0.05) as ooilammers onder VK-toestande gegroei, terwyl kleiner verskille tussen geslagsgroepe by VD-diere waargeneem is. VK-lammers het swaarder karkasse (P=0.0003), hoër uitslagpersentasies (P<0.05) en meer karkas vet (P<0.052) as VD -lammers vertoon. Geen verskille as gevolg van produksiestelsel is op die sagtheid van vleis (soos aangedui deur Warner-Bratzler skeurkragwaardes) en die binnespierse vetinhoud gevind nie. Daarenteen het sensoriese analises aangedui dat vleis van VK-lammers sappiger en sagter as vleis van VD- lammers was. Die sensoriese paneel kon nie verskille aangaande die aroma en geur van vleis tussen VK- en VD-vleis onderskei nie. Cholesterolvlakke was hoër vir VK-lammers as by VD-lammers. Die vlak van palmitiese suur (C16:0) was hoër (P=0.0375) in die Longissimus dorsi (LD) spier van VK-lammers. Vir binnespierse vet van die Biceps femoris (BF) spier was g-linoleniese suur (C18:3n-6) hoër (P<0.0001) in VK-lammers. Resultate vir binnespierse vet van die BF spier het verder bewys dat ramlammers die hoogste (P=0.0019) palmitiese suur (C16:0) and totale onversadigde vetsure (P = 0.0014) getoon het, hamels die hoogste (P=0.0260) α-linoleniese suur (C18:3n-3) en g-linolenese suur (C18:3n-6) getoon het terwyl ooilammers die hoogste (P=0.0014) versadigde vetsuurvlakke getoon het. Linoliese suur (C18:2n-6c) was hoër (P=0.0067) in die onderhuidse vet van VK-lammers terwyl VD-lammers meer linoliese suur (C18:3n-3) gehad het. Resultate vir niervet het getoon dat VD-voeding die persentasies van steariese (C18:0), linoleladiese (C18:2n-6t), α-linoleniese (C18:3n-3) and homo-g-linoleniese suur (C20:3n-6) verhoog (P<0.05) het relatief tot VK-voeding. Linoliese suur (C18:2n-6c) is deur VK-voeding verhoog (P=0.0372). Vir intermuskulêre vet het VD-lammers hoër linoleniese suur (C18:3n-3) en versadigde vetsure (P=0.0113 en P=0.0341) as VK-lammers gehad. Die totale onversadigde vetsure vir tussenspiere vet was hoër (P=0.0341) in VK-lammers in vergelyking met VD-lammers. Resultate van hierdie studie dui daarop dat verbruikers nie noodwendig tussen vleis van VD- en VK-lammers sal onderskei nie, alhoewel hulle dalk teen die sigbaar vetter vleis van VK-lammers kan diskrimineer. Geen definitiewe voordeel in terme van menslike gesondheid kon op grond van die chemiese samestelling van die vleis bevestig word nie. Vinniger groei van VK-lammers, en die korter produksiesiklus wat daarmee verband hou, mag onder sekere produksie stelsels ŉ voordeel wees. Die voordeel moet teen die hoër koste van VK-voeding en die voorkeur van verbruikers vir lam produksie in natuurlike omgewing opgeweeg word.

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21

Bernard, Jennifer. "Conception de systèmes de production innovants dans une dynamique dintensification laitière : cas des exploitations de polyculture-élevage relevant des périmètres de la réforme agraire dans le municipe dUnaí-MG, Brésil." Thesis, Montpellier, SupAgro, 2010. http://www.theses.fr/2010NSAM0036/document.

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Les éleveurs laitiers gèrent des systèmes complexes combinant production animale et production végétale. Dans un contexte d'évolutions rapides, les démarches de conception de systèmes de production doivent être renouvelées, et répondre à la diversité des situations des exploitations agricoles. La co-conception de systèmes innovants avec les producteurs eux-mêmes se présente comme une démarche intéressante. Les modèles d'exploitation permettent de représenter la complexité du système, mais leur utilisation comme outil d'accompagnement interroge les choix de développement. Ce travail propose une démarche d'accompagnement basée sur l'utilisation d'un modèle de simulation pour appuyer les réflexions de l'éleveur sur ses stratégies d'élevage. Les choix de développement s'appuient sur l'analyse du fonctionnement d'un échantillon de six exploitations. Trois exemples d'utilisation du modèle avec les producteurs sont présentés. Ils montrent comment les résultats du modèle alimentent la discussion autour du proj et de l'éleveur
Dairy farmers have to manage complex and mixed-farming systems. In the moving context of the agricultural sector, methods of conception of production systems must be renewed and fit the diversity of farmers conditions. The co-conception of production systems with farmers is the approach we want to defend. Whole-farm models help to picture the farming system's complexity but their use as advising services' tools raises questions in terms of model design choices. This PhD proposes an approach of advising services based on the use of a simulation whole-farm model to help farmers in designing their livestock strategies. The model design is based on the analysis of six dairy farms that constitute our study sample. We present three case-studies about the use of our model with dairy farmers. The case-studies give us insight about the capacity of the model's outcomes to generate debates with farmers about their own projects

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22

Scoones, Ian. "Livestock populations and the household economy : a case study from southern Zimbabwe /." Online version, 1990. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.281919.

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23

Hoffmann, Willem Hendrik. "Farm modelling for interactive multidisciplinary planning of small grain production systems in South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5269.

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Thesis (PhD (Agric) (Agricultural Economics)--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: A complex and volatile decision-making environment and constant pressure on product prices, due to the cost-price squeeze, complicates decision-making for grain farmers in the Western Cape. Furthermore, available alternative crops and cultivation practices are limited due to local soil and climatic conditions. The farm system itself is complex due to the interdependence of a variety of factors and the synergy resulting from specific sequences of cash and pasture crops. The aim of this research project was to establish a method that would contribute to identifying strategies to advance the profitability of grain production. Research in the grain industry is traditionally specialised within specific fields, such as, agronomy, soil science, entomology, agricultural economics, etc., causing a fragmentation of knowledge. To ensure that the systems nature of a complex farm is accommodated, various related research domains should be acknowledged and incorporated. The use of expert group discussions, as a research method, is suitable, firstly, for gathering information in a meaningful manner and, secondly, to stimulate individual creativity by presenting alternative perspectives provided by various participating experts. In support of expert group discussions, simulation models in the form of multi-period whole-farm models were developed. This type of modelling supports the accurate financial simulation of farms, while the user friendliness and adaptability thereof can accurately accommodate typical farm interrelationships, and quickly measure the financial impact of suggested changes to parameters. Suggestions made by experts during the group discussions can thus be quickly introduced into the model. The financial implications are instantly available to prevent further exploration of non-viable plans and to fine-tune the viable plans. Participants in the group discussions represent fields of expertise such as agronomy, soil science, entomology, plant pathology, the agricultural chemical industry, agricultural mechanisation. Also represented are professionals such as extension officers from local agribusinesses, local producers and agricultural economists. The dynamics of the group discussions are supported by each participant’s specific strengths and perspectives. For each relatively homogeneous production area of the Western Cape, a typical farm budget model was developed, which served as the basis for the group discussions. The budget models measure profitability in terms of the IRR (internal rate of return on capital investment) and affordability in terms of expected cash flow. For the Swartland, the homogeneous areas identified were Koeberg/Wellington, the Middle Swartland and the Rooi Karoo, and for the Southern Cape, the homogenous areas identified were, the Goue Rûens, Middle Rûens and Heidelberg Vlakte. A model of a typical farm in the Wesselsbron area was developed for comparison with the Western Cape farms. For each area the expected impact of climate change, fluctuating product and input prices, and the possible impact of partial conversion to bio-fuel production were evaluated in terms of expected impact on profitability. Various area-specific strategies were identified that could enhance the profitability of grain production: most of the strategies focused on optimising machinery usage and expanding or intensifying the livestock enterprise. The repeated successful use of the model in support of the expert groups in all the chosen study areas illustrates the value thereof for identifying and evaluating plans to increase the profitability of small grain production.
AFRIKAANSE OPSOMMING: 'n Komplekse en wisselvallige besluitnemingsomgewing, en konstante druk op produkpryse weens die koste/prys knyptang bemoeilik besluitneming op graanplase in die Wes-Kaap terwyl die beskikbare alternatiewe verbouingsgewasse en -praktyke beperk is weens plaaslike grond en klimatologiese eienskappe. Die boerderystelsel self is kompleks weens die interafhanklikheid van die dele daarvan en die sinergisme verkry deur byvoorbeeld die spesifieke orde van opeenvolging van kontant- en weidingsgewasse in die wisselboustelsel. Hierdie navorsingsprojek se doel is om 'n werkwyse te vestig wat die identifisering van strategieë te ondersteun wat moontlik die winsgewendheid van graanproduksie kan bevorder. Navorsing in die graanbedryf is tradisioneel gespesialiseerd binne 'n spesifieke navorsingsveld soos agronomie, grondkunde, entomologie en landbou-ekonomie. Dit gee daartoe aanleiding dat elk van hierdie velde op dimensies van die boerderystelsel fokus asof dit in isolasie bestaan. Om te verseker dat die stelselsgeaardheid van 'n komplekse boerdery effektief verreken word behoort navorsing erkenning te gee die interafhanklikheid van die dimensies van 'n boerdery. Ekspert groepbesprekings is 'n navorsingsmetode wat eerstens geskik is om kennis sinvol byeen te bring en tweedens om kreatiwiteit by deelnemers te stimuleer deur die blootstelling aan nuwe perspektiewe van kundiges van ander spesialiteitsvelde. Ter ondersteuning van die ekspert groepbesprekings is simulasiemodelle in die vorm van multi-periode geheelboerderybegrotings ontwikkel. Die tipe modellering ondersteun die akkurate simulasie van boerderye terwyl die gebruikersvriendelikheid en aanpasbaarheid daarvan die tipiese interverwantskappe van 'n boerdery akkuraat weergee en die impak van aanpassings aan die parameters van die boerdery model vinnig kan meet. Voorstelle deur die deelnemende eksperts kan dus vinnig aangebring word en die finansiële implikasie is dadelik beskikbaar. Deelnemers aan die ekspertgroepbesprekings het velde verteenwoordig soos agronomie, grondkunde, entomologie, die landbou chemiese bedryf, landbou meganisasie, plantpatologie, voorligtingsbeamptes van plaaslike agribesighede, plaaslike produsente en landbou-ekonome. Die dinamika van die groepbesprekings word ondersteun deur elke deelnemer se spesifieke sterkpunte en perspektief. Vir elke homogene produksiegebied in die Wes-Kaap is 'n aparte begrotingsmodel van 'n tipiese plaas vir daardie area ontwikkel. Hierdie modelle het gedien as die basis van die groepbesprekings. Die modelle meet die winsgewendheid van boerderye oor die langtermyn deur middel van die IOK (interne opbrengskoers op kapitaal investering) en die bekostigbaarheid in terme van verwagte kontantvloei. Binne die Swartland is die Koeberg/Wellington, Middel Swartland en Rooi Karoo as homogeen geïdentifiseer en vir die Suid-Kaap die areas van die Goue Rûens, die Middel Rûens en die Heidelberg Vlakte. 'n Tipiese plaas model is ook vir die Wesselsbron area ontwikkel om te vergelyk met die Wes-Kaap areas se modelle. Vir elke area is die verwagte impak van klimaatveranderings, fluktuerende produk- en insetpryse en die moontlike impak van 'n biobrandstofbedryf geëvalueer in terme van die verwagte impak op winsgewendheid. Verskeie area spesifieke strategieë is geïdentifiseer wat moontlik die winsgewendheid van graanproduksie kan bevorder. Die meeste strategieë fokus op die optimalisering van masjineriegebruik en die uitbreiding of intensifisering van die veevertakkings. Die herhaalde suksesvolle gebruik van die modelle ter ondersteuning van die ekspertgroepe in al die gekose studie areas illustreer die waarde daarvan vir die identifisering en evaluering van planne om die winsgewendheid van kleingraanproduksie te verhoog.

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24

Bradshaw, Terence L. "Comprehensive Assessment of Organic Apple Production in Vermont: Experience from Two Orchard Systems, 2006-2013." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/327.

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Despite substantial consumer demand and willingness to pay premium prices for organically grown fruit, apple growers in Vermont and other New England states have been slow to adopt certified organic practices. Barriers cited in the past to increased adoption of organic apple production in the region include susceptibility of traditionally grown cultivars to apple scab, lack of effective insect pest management materials, and few available effective options for fruit thinning. Recent changes in apple cultivar plantings in the region, introduction of new insect pest management materials, and advances in crop thinning justified an evaluation of organic apple production systems containing cultivars identified as important to the future of the apple industry. In 2006, two apple orchards were established at the University of Vermont Horticulture Research and Education Center in South Burlington, VT to comprehensively evaluate the five commercially-important apple cultivars of `Ginger Gold', `Honeycrisp', `Liberty', `Macoun', and `Zestar!' over eight growing seasons in two organically-managed orchard production systems, including a newly-planted high-density orchard (Orchard 1) and in an existing, medium-density orchard which was top-grafted to the new cultivars (Orchard 2). Parameters for tree growth and survival, crop yield, disease and arthropod pest incidence on foliage and fruit, and long-term economic return, including a twenty-year projection of net present value (NPV) of each cultivar in the two systems were evaluated in this study. `Ginger Gold', despite high incidence of some diseases on foliage and fruit, performed the best in both orchard systems overall. The cultivar was among the cultivars with the highest measurements of tree growth. `Ginger Gold', along with `Honeycrisp', had the highest cumulative net crop yield per tree in Orchard 1 and the highest in Orchard 2. Notably, apple scab on `Honeycrisp' foliage and fruit and `Zestar!' fruit in both orchards was at a level that was not significantly different from `Liberty', a scab-resistant cultivar on which no scab was observed. However, `Honeycrisp' had the highest incidence of fruit rots in both orchards, but it was not significantly different than `Zestar!' in Orchard 1. Management of lepidopteran pests of fruit was a major challenge on all cultivars over the years of the study. For most of the tree growth parameters and cumulative net crop yield, `Liberty' was among the lowest group of cultivars in both orchards. Cumulative net crop yield of both `Macoun' and `Zestar!' were also among the lowest in both orchards with the top-grafted `Macoun' and `Zestar!' trees having significant tree death compared to the other cultivars in Orchard 2. Harvested fruit were graded to commercial standards and cumulative gross and net income calculated from grade distribution, crop yield, and fruit price data. In Orchard 1, `Ginger Gold' and `Liberty' had greater cumulative gross income per hectare from 2006-2013, in excess of US$40,000, compared to `Liberty'. However, after management costs were deducted, all cultivars in Orchard 1 had negative cumulative net income of $-77,892 or less. In Orchard 2, all cultivars had positive cumulative net income for 2006-2013, and `Ginger Gold' had the highest at $109,717/ha. The twenty-year projected NPV was negative for all cultivars in Orchard 1, but in Orchard 2, all cultivars had positive NPV with `Ginger Gold' having the highest among the cultivars.

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25

Mohammed, Isiaka. "Study of the integration of the dromedary in the smallholder crop-livestock production systems in northwestern Nigeria /." Göttingen [Germany] : Cuvillier, 2000. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=008939812&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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26

Patton, Mark Evans Mr. "The Agricultural Growth and Malting Production of Barley Grains in Northeast Tennessee and Southwest Virginia." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etd/3061.

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The purpose of this study is to explore the history and production processes of beer and examines the components that contribute to its brewing. The narrative will provide a timeline of the processes that are required to create the product of beer beginning with the agricultural products and following the brewing processes that result in beer as the finished product. I will also examine the business of agriculture and grain processing and will provide some historical perspectives of grain, beer, and malting. I will also consider whether the growing, processing, and malting of grains in the East Tennessee and Southwest Virginia Region is feasible as demonstrated through this research and reported findings.

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27

Rocha-Bello-Bertin, Patricia. "Towards effective governance of information in a Brazilian agricultural research organisation." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14630.

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There are three different uses of the term 'information' in ordinary language: in the restricted sense, it means diverse types of material objects, such as data or documents ('information as thing'); alternatively, the term is used as in reference to the act of informing or becoming informed ('information as process'), or to equate to knowledge ('information as knowledge'). Each of these connotations represents a legitimate view of information in its own right, being equally significant to information-intensive organisations. The literature lacks studies that approach information from an integrative viewpoint, however. The purpose of this study was to explore and develop the notion of 'information governance' as an integrative, systemic approach to information in the context of research organisations. Soft Systems Methodology was used in a case study involving the Brazilian Agricultural Research Corporation. Qualitative data was gathered through in-depth interviews with researchers and information/knowledge managers, followed by a thematic, two-level analysis. From a 'macro level' of analysis (the wider Brazilian agricultural research system) it was found that, to solve increasingly complex research problems, collaborative, multidisciplinary networking is needed. On the other hand, competitive forces are continuously emanating from the systems of research steering, funds and resources' allocation, quality control, and recognition and reward. This conflict inhibits the collaborative sharing of 'information as thing' and 'as knowledge', disturbs internal communication flows and contributes to low levels of synergy and cross-departmental partnerships, ultimately affecting research outcomes. At a 'meso level' (the local practices and culture of agricultural knowledge production), different epistemic cultures were identified (named in vitro, in situ and in silico research), which respond differently to the opposing forces of collaboration and competition. Based on a deep understanding of the agricultural research system and underlying epistemic cultures, a framework for effective governance of information was developed. Action to improve the governance of information at Embrapa would involve nurturing an information culture that supports collaborative work. Given that interactions between researchers are determined by their individual pursuits and struggles, this would require a change in the corporate system of performance evaluation and reward, according to the different epistemic cultures.

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Bennett, James E. "The contribution of arable land allocations to cattle production systems in communal areas of central Eastern Cape Province, South Africa." Thesis, Coventry University, 2002. http://curve.coventry.ac.uk/open/items/0cb1c706-8922-b461-3e47-c40448a0103d/1.

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The communal (former homeland) areas of South Africa are characterised by high concentrations of black people many of whom live in extreme poverty. In recent years this has been exacerbated by the collapse of state-run farmer assistance schemes, which has resulted in very low levels of agricultural production in these areas. The new South African government has proposed the revitalisation of small-scale agriculture as an important mechanism for uplifting rural livelihoods here. This research was undertaken in the former homeland of Ciskei, in what is now central Eastern Cape Province. Here agricultural decline has resulted in large areas of land designated for crop production lying fallow in the long term. Livestock production offers greater livelihood potential in this region, and it was therefore posited that this essentially abandoned cropland might be better utilised as a permanent grazing resource for livestock, particularly cattle. The research sought to characterise current levels and patterns of utilisation of arable land by livestock and how this land might be more effectively managed as a grazing resource and thereby improve levels of livestock production. Enormous variation was found in the contribution made by arable land allocations to cattle production systems in communal areas of this region. From a social perspective grazing management systems were found to depend largely on the availability of grazing resources. Where these were plentiful, control was exercised at a communal level although this tended to devolve to the individual level as grazing areas became overutilised. Considerable variation was also evident at the ecological level. Pasture quantity and quality was largely dependent on local ecotopes and land management strategies. This in turn exerted a strong influence on cattle foraging behaviour and the extent to which they could satisfy their nutritional intake requirements and thereby maintain bogy condition. Recommendations are advanced for improving cattle production systems, which take adequate account of the social and ecological heterogeneity of the central Eastern Cape region.

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Kabura, Nyaga Elizabeth A. "Smallholder cashcrop production and its impact on living standards of rural families in Kenya /." Weikersheim : Margraf, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2999150&prov=M&dok_var=1&dok_ext=htm.

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Mores, Giana de Vargas. "Dynamics of food production and consumption in Brazil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/184888.

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O agronegócio expressa-se de múltiplas formas e tem repercussões nos sistemas alimentares e no comportamento das populações locais e globais. As estimativas sugerem que o Brasil se tornará o maior produtor mundial de alimentos nas próximas décadas. Assim, cumpre-se examinar as commodities agrícolas brasileiras e analisar as diferentes mudanças temporais e geográficas relacionadas à produção e ao consumo de alimentos no país. Com vistas a apresentar uma investigação científica que contribua para a construção do conhecimento da dinâmica da produção e do consumo de alimentos no Brasil, esta tese inclui pesquisas interdisciplinares que fornecem análises complementares para o tema proposto. O objetivo principal deste estudo é composto por dois aspectos que envolvem os sistemas agroalimentares e as suas dinâmicas. O primeiro refere-se à produção de alimentos no Brasil – especificamente como as diferentes expressões do agronegócio na produção agrícola e pecuária evoluíram – enquanto o segundo aspecto analisa como a população brasileira mudou seus padrões alimentares. Assim, a tese examina a participação da região do Centro-Oeste brasileiro na alteração da distribuição da produção agrícola brasileira. Os movimentos dos pontos médios geográficos dos principais produtos agrícolas brasileiros, ocorridos entre 1990 e 2015, parecem corresponder às mudanças geográficas ocorridas na produção agrícola e no uso da terra desta região durante o período analisado. Esta pesquisa também apresenta as mudanças geográficas relacionadas ao agronegócio brasileiro e discute como elas se refletem nos padrões alimentares de sua população, assim como na heterogeneidade da aquisição de alimentos entre os estados brasileiros. A relação entre o agronegócio e a sustentabilidade é necessária para melhorar a produção e a acessibilidade aos alimentos e preservar os recursos naturais. Nesse sentido, são necessários novos modelos de consumo e cadeias sustentáveis de suprimentos de alimentos para mitigar este problema. A análise fenomenológica realizada neste trabalho pode oferecer uma visão do agronegócio às partes interessadas, no que diz respeito ao panorama dos principais produtos que podem impulsionar o desenvolvimento sustentável da agricultura brasileira.

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Kirsch, Heitor Marcos. "Sistemas produtivos e degradação ambiental : uma análise comparativa em dois municípios no oeste do estado de Mato Grosso-MT." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/13496.

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Tradicionalmente as definições do espaço rural vinham sendo associadas à idéia de local onde se realiza a produção agrícola. Mais recentemente, a partir de um enfoque onde o território rural passa a ser compreendido como um espaço multifuncional e multisetorial, possibilita uma redefinição do conteúdo das formas convencionais de desenvolvimento rural e das relações que freqüentemente são estabelecidas entre a sua configuração socioeconômica e os processos de degradação ambiental. O presente estudo se propõe a verificar a relação que se estabelece entre o processo de modificação do ambiente físico e o padrão de desenvolvimento produtivo que foi implantado no oeste do estado de Mato Grosso, tomando como referência grupos de agricultores distintos, nas localidades de Pontes e Lacerda e Campos de Júlio. Em Pontes e Lacerda, localizada numa região de transição entre os biomas do pantanal matogrossense e a floresta amazônica brasileira, foram entrevistados 27 agricultores com características de produção familiar, em áreas inferiores a 400 hectares. Em Campos de Júlio, localizada no cerrado do planalto central brasileiro e já nas proximidades da região amazônica, foram investigados 20 agricultores com áreas acima de 400 hectares, com uma produção agrícola mecanizada. Uma característica que assemelha a ocupação destes territórios é que são resultantes do processo migratório intra-estadual de ocupação de fronteira agrícola ocorrido entre o final da década de 60 até o final da década de 80. Os resultados encontrados sugerem que o processo de modificação deste meio físico que se constata em ambas as localidades é influenciado por uma associação positiva que estabelecem entre o processo de desmatamento e uma suposta melhoria nas suas condições de produção.
Traditionally, the definitions of rural space had been associated to the idea of a site where the agricultural production takes place. More recently, from the perspective in which the rural area can be understood as a multifunctional and multisectional space, it is possible to redefine the content of the conventional forms of rural development and the relations which are frequently established between its social-economical configuration and the processes of environmental degradation. The present study is aimed at verifying the relation between the process of modification of the physical environment and the model of productive development established in the western part of Mato Grosso State, taking as reference different groups of rural producers, in the localities of Pontes e Lacerda and Campos de Júlio. In Pontes e Lacerda, located in a region of transition between the biomas of the Pantanal of Mato Grosso and the Brazilian Amazon forest, 27 agriculturists were interviewed, all of them with characteristics of a familiar production, in areas inferior to 400 hectares. In Campos de Júlio, located in the “cerrado” of the Brazilian central plateau and in the surroundings of the Amazon region, 20 agriculturists were investigated, on areas over 400 hectares, and with a mechanized agricultural production. A feature which is common to the occupation of both territories is the fact that they are the result of the intrastate migratory process of occupation of agricultural border which took place between the late 60’s and the end of the 80’s. The achieved results suggest that the process of modification of this physical environment, which can be observed in both of these places, is influenced by a positive association established between the process of deforestation and a presumed improvement in their productive conditions.

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Öckerman, Frode. "Climate impact assessment of coupling biogas production to agricultural and energy systems: crop variety of Solaris energy tobacco in Marble Hall, South Africa." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295890.

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In the context of global energy shortage and climate change, developing local biogas plants coupled with agricultural systems can become an important strategy for cleaner rural energy and sustainable agriculture. In this research, a Life Cycle Assessment (LCA) method was applied to compare the climate impact of two essentially different systems: 1) Scenario I: an agricultural system based on the cultivation of 11 hectares of energy tobacco primarily for seed production; 2) Scenario II: a hypothetical Scenario Investigating the climate impact concerned with a crop variety – a higher yielding variety cultivated for both seed and biomass - and introducing biogas production. Both scenarios focus on the energy tobacco biomass residues. The overall aim of the study was to evaluate the climate impact of these two scenarios in the agricultural and energy system in Marble Hall, Limpopo Province, South Africa. The biogas was used for electricity production, replacing coal-based electricity on the grid. Biomass residues were chosen as feedstock for biogas production since this crop presently receives much attention in the region as the oily seeds can be used to produce sustainable jet fuel. Results from the modelling show that Scenario II would provide a positive climate impact: a 43% reduction of greenhouse gases compared to Scenario I. The higher yielding crop variety in Scenario II means that there is also potential to produce more sustainable jet fuel to replace conventional aviation fossil fuel. Taking this into account, the biogas scenario can reduce emissions by 79% compared to the base case. An analysis of the results indicates that there are several variables in the system model that are uncertain and sensitive to change, proving that more research is necessary to make robust conclusions about the validity of the presented results.

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Schaak, Henning [Verfasser], Oliver [Akademischer Betreuer] Mußhoff, Oliver [Gutachter] Mußhoff, Achim [Gutachter] Spiller, and Ulf [Gutachter] Liebe. "Agricultural and societal perspectives on pasture-based livestock production systems in Germany / Henning Schaak ; Gutachter: Oliver Mußhoff, Achim Spiller, Ulf Liebe ; Betreuer: Oliver Mußhoff." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1201548950/34.

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Schaak, Henning [Verfasser], Oliver [Akademischer Betreuer] Mußhoff, Oliver Gutachter] Mußhoff, Achim [Gutachter] [Spiller, and Ulf [Gutachter] Liebe. "Agricultural and societal perspectives on pasture-based livestock production systems in Germany / Henning Schaak ; Gutachter: Oliver Mußhoff, Achim Spiller, Ulf Liebe ; Betreuer: Oliver Mußhoff." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:7-21.11130/00-1735-0000-0005-12C5-8-7.

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35

Kumalo, Molefi Petrus. "Characterization of sheep and goat production systems amongst small-scale farmers in the Southern Free State." Thesis, Bloemfontein : Central University of Technology, Free State, 2014. http://hdl.handle.net/11462/266.

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Mosena, Marlova. "Agricultura em áreas frágeis : as transformações decorrentes do processo de arenização em São Francisco de Assis/RS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15361.

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O processo de arenização, decorrente de uma dinâmica hídrica e eólica sobre um substrato arenoso, tem sido acelerado em função das mudanças nos sistemas produtivos, ao longo do tempo, em alguns municípios da Região Sudoeste do Rio Grande do Sul. Isto tem acentuado a diferenciação entre os produtores rurais, o que permite reconhecer que a realidade da agricultura e das unidades de produção é complexa e heterogênea. Visando compreender esta realidade, partiu-se do seguinte questionamento: Como estão ocorrendo as transformações na agricultura nas “áreas frágeis” de São Francisco de Assis, diante das mudanças nos sistemas de produção decorrentes da aceleração do processo de arenização neste município? Este estudo pretendeu avaliar a influência do fenômeno da arenização sobre as transformações nos sistemas de produção de São Francisco de Assis/RS. O referencial teórico adequado à compreensão desta dinâmica, por apreender a complexidade das transformações históricas e da diversidade geográfica das agriculturas, foi a Teoria dos Sistemas Agrários. A reconstituição dos sistemas agrários do município permitiu diferenciar seis grandes momentos na sua evolução. O recorte geográfico e da paisagem permitiu definir como área de estudo a Microbacia Hidrográfica Sanga d’Areia a partir da qual delineou-se um estudo de caso no qual definiu-se como unidade de análise a Unidade de Produção Agropecuária (UPA). A análise dos dados permitiu inferir que, apesar de ter ocorrido a adequação dos sistemas produtivos de algumas UPA ao aumento das áreas afetadas pelo processo de arenização, este fato isolado não garantiu a manutenção dos produtores no processo produtivo.
The arenization process, resultant of hydric and wind dynamics over sandy soils, has been accelerated as an outcome of changes in the productive systems, along time, in some municipalities in southwestern Rio Grande do Sul. This has increased the differentiation between rural producers, allowing to identify that reality of agriculture and production unities is complex and heterogenous. Aiming to understand this reality, we start from the following inquiry: How is taking place the changes in agriculture on “fragile lands” of São Francisco de Assis, in face of changes in the productive systems resulted from the acceleration of the arenization process in that municipality? This study intended to evaluate the influence of the arenization phenomenon on the changes in the productive systems from São Francisco de Assis/RS. The theoretical background adequate to understand this dynamic, for perceiving the complexity of historical changes and geographic diversity of agriculture was the Theory of Agrarian Systems. The reconstitution of agrarian systems in the municipality allowed differentiates six major moments in its evolution. The geographic and landscape divisions permitted to define the Sanga d’Areia micro basin as the study area, from where we delineate a case study with the Agropecuary Unit of Production (UPA) defined as the unit of analysis. The data allowed to infer that, even with the adaptation occurred in the productive systems in some UPA to the increase in areas affected by the process of arenization, this fact alone did not guarantee the maintenance of the producers in the productive process.

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Page, Girija. "An environmentally-based systems approach to sustainability analyses of organic fruit production systems in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Sustainable Agricultural Systems at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/825.

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An environmentally-based systems approach to sustainability analyses of organic fruit production systems in New Zealand. This research introduces an approach for the assessment of the sustainability of farming systems. It is based on the premises that sustainability has an environmental bottom line and that there is very limited substitutability between natural capital and other forms of capital. Sustainability assessment is undertaken through analyses of energy and material flows of the system and their impacts on the environment. The proposed sustainability assessment approach is based on two high level criteria for sustainability: efficient use of energy and non-degradation of the environment from energy and material use. Sustainability assessment of organic orchard systems in New Zealand was undertaken to demonstrate this approach. Five indicators which address the two criteria for the sustainability of the orchard systems are the energy ratio, the CO2 ratio, changes in the soil carbon level, nutrient balances, and the leaching of nitrogen. Organic kiwifruit and organic apple systems are modelled based on their key energy and material flows and their interactions with the natural environment. The energy and material flows are converted into appropriate energy and matter equivalents based on coefficients taken from the published literature. Sustainability indicators are estimated over one growing season using two computer modelling tools, Overseer® and Stella®, in a life cycle approach. Sustainability assessment of the organic orchard systems suggests that the approach is useful for evaluating energy use and key environmental impacts that occur in soil, water and atmosphere. The results indicate that the model organic orchard systems are sustainable in terms of energy use and are a net sink of CO2-equivalent emissions. The implication of this result is that organic orchard systems potentially could trade carbon credits under the Kyoto Protocol. The findings also suggest that the sustainability assessment approach is capable of identifying the trade-offs within the sustainability indicators associated with particular management practices. Further research to improve and validate the proposed approach is essential, before it can be practically used for decision making at the orchard level and for policy making at the national level.

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Ferreira, Catarina Isabel Almeida. "Production and application of biowaste-based adsorbents for the removal of fish anaesthetics in recirculating aquaculture systems." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/18042.

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Doutoramento em Ciências e Engenharia do Ambiente
A partir de 1960 a atividade aquícola aumentou abruptamente, tornando-se o setor de produção de alimentos de maior crescimento. A implementação de sistemas de aquacultura intensiva contribuiu para esse acentuado desenvolvimento; contudo, a sua prática impõe elevados riscos relativos ao bem-estar dos peixes, tornando-os vulneráveis a doenças, stress e a condições ambientais adversas. Para o controlo do stress são utilizados anestésicos, sendo os mais comuns a tricaína, benzocaína e 2-fenoxietanol. Estes fármacos são administrados solubilizando-os na água dos tanques e, consequentemente, contaminando-a. Atualmente, as instalações de criação intensiva estão equipadas com sistemas de recirculação em aquacultura (SRA) onde a água é tratada e reciclada. Os SRAs típicos são eficazes na remoção de sólidos suspensos e no controlo do nível de carbono orgânico dissolvido e amónia mas não estão preparados para eliminar fármacos. O processo de adsorção, utilizando carvões ativados, é uma tecnologia bem documentada e eficaz na remoção de contaminantes orgânicos, incluindo fármacos, e tem sido proposta como processo de tratamento terciário em SRA; no entanto, os carvões ativados são dispendiosos. O projeto desta tese visa a produção de adsorventes alternativos, usando bioresíduos agrícolas e industriais como percursores, capazes de competir com os carvões ativados comerciais, recorrendo a técnicas simples, baratas e amigas do ambiente. O principal objetivo consiste na aplicação dos adsorventes produzidos na remoção de anestésicos veterinários em SRA. Relativamente à valorização dos resíduos testados, os resultados mostraram que os bioresíduos agrícolas (casca de Eucalipto, sementes de uva, caroços de pêssego, cascas de nozes, resíduos de azeitona e cascas de amendoim) podem competir com os carvões fósseis em aplicações de combustão (por exemplo, produção de combustível e energia). Por outro lado, os biocarvões produzidos por pirólise dos bioresíduos industriais (lamas primárias e biológicas da indústria papeleira) são adsorventes promissores, uma vez que os resultados revelaram elevadas capacidades de adsorção com bom desempenho em sistemas fechado e contínuo. Os adsorventes produzidos a partir das lamas biológicas podem ser aplicados no tratamento de águas de aquacultura intensiva com o mesmo desempenho independentemente das condições da água (temperatura, salinidade e presença de matéria orgânica e inorgânica). Sendo as lamas produzidas em larga escala, o custo associado aos percursores destes adsorventes é nulo, com a vantagem de eliminar os esforços de gestão destes resíduos. Além disso, contrariamente aos carvões ativados comerciais, o método de produção usado evita o uso de agentes químicos e permite a recuperação de energia, sendo considerado um processo amigo do ambiente. Estes factos aliados aos bons resultados obtidos na remoção de anestésicos veterinários indicam que o uso de adsorventes a partir de lamas da indústria papeleira poderá ser uma alternativa a aplicar em SRA.
The aquaculture activity has steeply increased since the 1960’s, being the fastest growing food production industry. The implementation of intensive aquaculture systems has contributed to this impressive development in the world food fish production; however, this practice imposes high risks on the welfare of fish, making them vulnerable to adverse impacts from disease, stress and also from environmental conditions. For the fishes’ stress control, anaesthetics are administered and the most commonly used are tricaine, benzocaine and 2-phenoxyethanol. These pharmaceuticals are administered by solubilization in the fish tank’s water, which, therefore, becomes contaminated. Nowadays, intensive aquaculture facilities are equipped with a recirculating aquaculture system (RAS) where the water is treated and remains in a closed circuit. A typical RAS is planned to remove suspended solids and to control dissolved organic carbon and ammonia levels but the processes used are not prepared to eliminate pharmaceuticals. The adsorption process, using activated carbons, is a well-established technology for the removal of organic contaminants, including pharmaceuticals, and it has been proposed as tertiary treatment in RASs; however, activated carbons are very expensive. The project of this thesis aims at the production of alternative adsorbents, using agricultural or industrial biowastes as precursors, by means of a simple, inexpensive and environmentally friendly production technique and capable to compete with the commercial activated carbons. The objective is the application of the produced adsorbents for the removal of fish anaesthetics from water in the RASs. A first evaluation about the valorisation of such residues showed that the agricultural biowastes (Eucalyptus bark, grape seeds, peach stones, walnut shells, olive waste and peanut shells) can compete with fossil coals in combustion applications (e.g., fuel and power generation). On the other hand, the biochars produced by the pyrolysis of the industrial biowastes (primary and biological paper mill sludge) have favourable properties to be used as adsorbents. The adsorption results revealed highest adsorption capacities using paper mill sludge-based adsorbents with good performance in both batch and continuous (fixed-bed column) systems. Also, it was observed that the biological sludge-based adsorbent can be employed in intensive aquaculture wastewater treatment with the same performance independently of the water characteristics (temperature, salinity and presence of organic and inorganic matter). Overall, these sludges are produced in large scale, therefore the cost associated with the precursor of these alternative adsorbents is null with the additional benefit of eliminating managing costs of such residues. Moreover, contrarily to commercial activated carbons, the production process used avoids the utilization of activating chemicals and allows the recovery of energy from these residues, so it may be considered an environmentally friendly process. For these reasons, and allied to the good results obtained for the removal of fish anaesthetics, the use of paper mill sludge-based adsorbents may be an alternative choice to be applied in RASs.

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Souza, Danielle Thaís Barros de. "Seleção de indicadores para gestão sustentável da olericultura em Itabaiana/SE." Universidade Federal de Sergipe, 2008. https://ri.ufs.br/handle/riufs/4269.

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Sustainable agriculture has been an increasing concern for the diverse involved social segments. The use of tools as indicating of sustainability in horticulture productive systems becomes important at a time that can contribute for the reduction of its ambient liabilities. This research had as objective generality to consider pointers of sustainability for horticulture producers in the city of Itabaiana in the State of Sergipe, in order to contribute for identification and monitor of the production systems. As specific objectives, the study aims to characterize the production systems and select pointers for sustainable management of the productive systems. It is a study of field of exploratory and descriptive type carried from half-structuralized interview with 28 proprietors of horticulture cultures of the city of Itabaiana - Sergipe, selected for being supplying of the Net of G Barbosa supermarkets. The pointers had been selected on the basis of the information collected and in the method considered for the United Nations Environment Program, known as Pressure / Estate/ Answer (P.E.A.). On the basis of the characterization of the production systems evidenced a series of problems that if observed for the optics of the sustainability present fragilities in the social, economic and ambient dimensions. 43 pointers of sustainability had been selected for the evaluation aiming to monitor which attributes of the activity may be contrary with the objectives.
A agricultura sustentável tem sido uma preocupação crescente pelos diversos segmentos sociais envolvidos. A utilização de ferramentas como indicadores de sustentabilidade em sistemas produtivos de olerícolas torna-se importante uma vez que pode contribuir para a redução do seu passivo ambiental. Esta pesquisa teve como objetivo geral propor indicadores de sustentabilidade para olerícolas na cidade de Itabaiana no Estado de Sergipe, a fim de contribuir para identificação e monitoramento dos sistemas de produção. Como objetivos específicos, o estudo visa caracterizar os sistemas de produção, e selecionar indicadores para gestão sustentável dos sistemas produtivos. Trata-se de um estudo de campo do tipo exploratório e descritivo realizado a partir de entrevista semi-estruturada com 28 proprietários de olericulturas da cidade de Itabaiana/ SE, selecionados por serem fornecedores da Rede de supermercados G Barbosa. Os indicadores foram selecionados com base nas informações coletadas e no método proposto pelo Programa das Nações Unidas para o Meio Ambiente, conhecido como Pressão/ Estado/ Resposta (P.E.R.). Com base na caracterização dos sistemas de produção constatou-se um serie de problemas que se observados pela ótica da sustentabilidade apresentam fragilidades nas dimensões social, econômica e ambiental. Foram selecionados para a avaliação 43 indicadores de sustentabilidade visando monitorar quais atributos da atividade podem estar desconformes com os objetivos.

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Thomson, Sean Richard. "Methane Production by a Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1329.

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Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping. In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced by reciprocation mixing to decrease pumping costs and the risk of media clogging. Three packed-bed digesters containing walnut shells as media were constructed at the on-campus dairy and studied for about six months. Over that time, several organic loading rates (OLRs), measured as both chemical oxygen demand (COD) and volatile solids (VS) were applied to the new packed-bed digesters to allow modeling of methane production. The influence of temperature on methane production was also investigated. Additionally, the study measured solids accumulation in the walnut shell packed-bed as well as the effectiveness and durability of walnut shells as packing media. Finally, a simple economic analysis was developed from the methane model to predict the financial feasibility of packed-bed digesters at flush water dairies under similar OLR conditions. Three methane production models were developed from organic loading: saturation-type (following the form of the Monod equation), power and linear. The models were evaluated in terms of regression analysis and the linearity of experimental to predicted methane production. The best model was then chosen to develop the economic predictions. Economic predictions for packed-bed digesters were calculated as internal rate of return (IRR) using the methane models along with additional input variables. Comparisons of IRRs were made using electric retail rates of $0.10 to $0.20 per kilowatt-hour and capital cost subsidies from zero to 50%. Sludge accumulation in the packed-bed was measured via change in porosity, and walnut shell durability was measured as the change in mass of representative walnut shells over the course of the study. The linear-type model of methane production from volatile solids OLR best represented this data set. Digester temperature was not found to influence methane production in this study, likely due to the small daily average ambient temperature range experienced (14°C to 24°C) and the greater influence of organic loading. Porosity of the walnut shell packed-bed decreased from 0.70 at startup to 0.34±0.06 at the end of the six-month study, indicating considerable media fouling. Sludge accumulated in each digester from zero at startup to 281±46 liters at termination. Walnut shells in the packed-bed lost on average 31.4±6.3% mass during the study period which may be attributed to degradation of more readily bio-degradable cellulose and hemi-cellulose within the walnut shells. Given the predicted methane production and media life, at present, the economic outlook for packed-bed digesters at commercial dairies is quite dependent on utility electrical rates, available subsidies and future improvements to packed-bed digester technology. The predicted IRRs ranged from below 0% (at 0% capital subsidy and $0.10/kWh) up to 25% (at 50% capital subsidy and $0.20/kWh) at large dairies (3000 milking cows). Increases in organic loading were not shown to necessarily increase IRR, particularly at OLRs above 10 g/Lliquid-d (as COD or VS). Ultimately, to better assess the value of packed-bed digesters for flush dairies, additional study is needed on topics such as sludge accumulation prevention, long-term walnut shell degradation, dairy barn flush water mixing, and more detailed economic analysis.

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Senna, Ana Júlia Teixeira. "Fatores determinantes da emergência dos sistemas de produção frutícola." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10419.

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Os estudos dos sistemas agrícolas em geral, incluindo os sistemas de produção frutícola, com freqüência abordam a sua configuração e dinâmica numa ótica ex-post à sua origem e formação. Neste trabalho os sistemas agrícolas foram analisados numa ótica ex-ante. As variáveis determinantes da emergência dos sistemas de produção frutícola foram identificadas, com vistas à construção de um modelo de emergência destes sistemas. Inicialmente, por meio de entrevistas com experts, foram identificadas as variáveis percebidas como determinantes da emergência de um sistema de produção frutícola consolidado, localizado no Vale do Rio São Francisco, na Região Nordeste do Brasil. A seguir, estas variáveis foram avaliadas, quanto à sua importância, na emergência de oito sistemas de produção frutícola menos desenvolvidos, localizados no estado do Rio Grande do Sul, sendo que destes, cinco sistemas são focalizados na citricultura e três na persicultura. Assim foi possível determinar um conjunto de variáveis que representam as condições básicas para a emergência de sistemas de produção frutícola. As condições edafoclimáticas, a demanda do mercado, o apoio tecnológico, a existência de mão-de-obra especializada, a infra-estrutura produtiva na região, as condições das estradas e a existência de uma liderança foram as variáveis que receberam os maiores escores de importância para a emergência. As variáveis relativas à logística, ao apoio governamental, ao envolvimento de múltiplos produtores, instituições e empresas complementares do sistema de produção frutícola, complementam os condicionantes da plena expressão das propriedades características dos sistemas emergentes. A identificação dessas variáveis pode ajudar nas decisões sobre iniciativas de estímulo de emergência de sistemas de produção frutícola desejados, embora a configuração do sistema resultante destas iniciativas não possa ser antevista. O próximo passo seria testar essas variáveis em outros tipos de sistemas agrícolas, para modelagem de uma equação da emergência dos sistemas agrícolas em geral.
General studies on agricultural systems, including fruit production systems, often approach their configuration and dynamics under an ex-post viewpoint to their origin and formation. In this work the agricultural systems were analyzed in their ex-ante aspects. The variables, which determine the emergence of fruit production systems were identified, and considered for the construction of a model of emergence of these systems. At first, through interviews with experts, it was possible to identify the variables perceived as determinant for the emergence of a consolidated fruit production system, located in the Sao Francisco River Valley, Brazilian northeastern region. Later, such variables were evaluated in terms of importance for the emergence of eight less developed fruit production systems located in the state of Rio Grande do Sul, of which five were focused on citrus culture, and three were focused on peach culture. A set of variables were determined that represent the basic conditions for emergence of fruit production systems, which might represent the bases for emergence and development of other fruit production systems. Edaphic-climatic conditions, market demand, technological support, availability of skilled labor force, productive infra-structure in the region, road conditions, and the existence of leadership were the variables that received the highest scores of importance for the emergence. The variables involving infrastructure and logistics, government support, market and participation of multiple producers, institutions and complementary companies of the fruit system complete the other conditioning aspects of the full expression of the characteristic properties of emerging systems. The identification of these variables could help in processes of decision making, regarding initiatives to stimulate emergence of the fruits production systems, although the resulting configuration of the systems cannot be forecasted for sure. The next step in this kind of study would be to test these variables in other agricultural systems types, for modeling of an equation of the agricultural systems emergence in general.

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Silva, Jesús, Palma Hugo Hernández, Núẽz William Niebles, David Ovallos-Gazabon, and Noel Varela. "Time Series Decomposition using Automatic Learning Techniques for Predictive Models." Institute of Physics Publishing, 2020. http://hdl.handle.net/10757/652144.

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This paper proposes an innovative way to address real cases of production prediction. This approach consists in the decomposition of original time series into time sub-series according to a group of factors in order to generate a predictive model from the partial predictive models of the sub-series. The adjustment of the models is carried out by means of a set of statistic techniques and Automatic Learning. This method was compared to an intuitive method consisting of a direct prediction of time series. The results show that this approach achieves better predictive performance than the direct way, so applying a decomposition method is more appropriate for this problem than non-decomposition.

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Atadja, Franklin Komla. "Sustainability Challenges for Maize and Cassava Farmers in Amankwakrom Subdistrict, Ghana." Thesis, Walden University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10243184.

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Agricultural system in Ghana underperformed because of limited financing, which constrained some small-scale maize and cassava farmers. The purpose of this case study design was to explore the methods that some small-scale maize and cassava farmers in Amankwakrom Subdistrict used in obtaining farm financing. Two themes from the literature review were a lack of collateral for small-scale farm financing and the small-scale farmers cooperative associations? role in farm financing. Regional-scale management sustainability index formed the conceptual framework for this study. Data collection included semistructured face-to-face interviews with 8 fluent English speaking small-scale maize and cassava farmers who have obtained farm financing in the previous years. Using the Microsoft Excel and Non-numerical unstructured data indexing and theorizing software program for data analysis method, 3 major themes emerged: the farmer?s membership benefits of working in cooperative associations; farmer?s ability to provide the collateral requirements for the financial institutions; and farmer?s good loan repayment history. The study findings indicated that some small-scale maize and cassava farmers obtained farm loans because they used the cooperative associations as their collateral assets in order to satisfy for the requirements of the financial institutions. Social implications include the potential to guide the small-scale maize and cassava farmers to access farm credits to use in expanding their farm sizes. Expansion in farm sizes may result in more maize and cassava production that can help eliminate hunger and reduce poverty in the Amankwakrom Subdistrict of Ghana.

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Musunda, Bothwell Zvidzai. "Evaluation of cover crop species for biomass production, weed suppression and maize yields under irrigation in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/347.

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Achieving high biomass yields of cover crops has been a challenge to the success of Conservation Agriculture (CA) practices in the Eastern Cape (EC). A study was conducted to evaluate strategies for optimizing cover crop biomass production. Trials were carried out to screen summer and winter cover crops, as well as evaluate intercropping patterns and planting dates for biomass, weed suppression and subsequent maize yield under irrigation. Four summer legume cover crop species were evaluated under a Randomised Complete Block Design (RCBD) design. The cover crops were fertilized with 13.34 kg ha-1 of N, 20 kg ha-1 P and 26.66 kg ha-1 K. In the 2008/09 summer season a maize crop was superimposed on the 2007/08 screening trial under no-till. The crop was fertilized with 60 kg ha-1 of N. An intercropping trial was conducted over two seasons as a way of investigating the best way of incorporating cover crops into farmers cropping systems. This was done bearing in mind the limitation of resources such as land. The trial evaluated 3 factors laid as a 2 x 2 x 3 factorial arranged in a split-plot design. The main factor was cover crop planting date (planting at maize planting or 2 weeks after maize planting). The sub plot factor was intercropping pattern (strip intercropping and between row intercropping). A trial was also conducted to evaluate the effect of planting date (End of April and mid May) and four winter legume cover crop species on cover crop biomass, weed suppression and maize grain yield. The experiment was laid out as a Randomised Complete Block Design (RCBD) replicated 3 times. In the subsequent summer season a maize crop was superimposed on the winter trial to test the residual effects of the cover crop species. Another study was conducted to evaluate winter cereal cover crop species for biomass accumulation, weed suppression and subsequent maize grain yield. The cover crops as well as a weedy fallow control plot treatments were laid out as a Randomised Complete Block Design replicated 3 times. In the subsequent summer season a maize crop was superimposed on the site under no-till to evaluate the residual effect of the cover crops on maize. The results showed sunhemp, cowpea and lablab as the best cover crops with high biomass and weed suppression whilst mucuna was the least. Sunhemp consistently yielded higher cover biomass averaging 11200 kg ha-1 over the two seasons whilst mucuna had a consistently lowest average biomass yield of 4050 kg ha-1. These cover crops were above the critical 6 t ha-1 for effective weed suppression. There was a significant (p<0.01) relationship of cover crop dry weight and weed dry weight in both seasons. Subsequent maize grain yield was significantly higher in the sunhemp plots (64.2 %) than the weedy fallow plot. Mucuna, lablab and cowpea had maize grain yield increases of 16.6%, 33% and 43.2% respectively. Intercropping cover crops at maize planting yielded higher cover crop dry weights than a delay in intercropping cover crops. A delay in intercropping resulted in significantly higher average maize grain yield of 4700 kg ha-1 compared to intercropping at maize planting (3800 kg ha-1) and sole maize (4300 kg ha-1) over the two seasons. Strip intercropping also yielded higher (5000 kg ha- 1) average maize grain yield compared to row intercropping (3600 kg ha-1) and sole maize (4300 kg ha-1). There was a significant (p<0.05) relationship between cover crop dry weight in the 2007/08 season and maize grain yield in the 2008/09 season. Early planting grazing vetch gave the highest biomass yield of 8100 kg ha-1 whilst early planted red clover had the lowest biomass of 635 kg ha-1. Low weed dry weights were also obtained from the early planted grazing vetch as opposed to the other treatments. There was a significant (p<0.001) relationship of cover crop dry weight and weed dry weight. In the subsequent 2008/09 summer season early planted grazing vetch had the highest maize yield of 7500 kg ha-1 which was 56.3 % more than the weedy fallow plot had 4800 kg ha-1. The weedy fallow plot also had high weed infestation than the cover crop plots. There were significant (p<0.01) relationships between cover crop dry weight and maize grain yield, winter weed dry weight and maize grain yield and summer weed dry weight and maize grain yield. The results also showed triticale (13900 kg ha-1) as the best winter cover crop for biomass production. Italian ryegrass (6500 kg ha-1) produced the least amount of biomass. In The subsequent maize crop white oats gave highest maize grain yield (6369 kg ha-1) which was 33 % more than the weedy fallow plot (4784 kg ha- 1). There were also significant (p< 0.01) relationships of maize grain yield and winter weed dry weight, maize grain yield and summer growing weeds. The various studies demonstrated that there is opportunity for high biomass production under small scale farmers irrigated conditions using cover crops both in winter and summer. Best bet cover crops were sunhemp, cowpea and lablab for summer and triticale, white oats, barley, Italian ryegrass and grazing vetch for winter. Cover crops can also be incorporated into farmers cropping systems as sole crops or intercrops within the maize based cropping systems. Strip intercropping can be used by farmers as a way of introducing cover crops. Critical to achievement of high biomass is the time of planting cover crops with high biomass when planting is done early. A 2 week delay in strip intercropping cover crop into maize can be used as a way of incorporating cover crops into farmers cropping systems with minimal maize yield reduction.

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Freitas, Douglas Siqueira. "Densidade microbiológica e potencial metabólico em cerrado nativo e cultivado." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4366.

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The conservation of native and cultivated soils quality in the Cerrado region, seen by a microbiological point of view, has been discussed with both ecological as productive focus. In this work, the quality of native Cerrado was contrasted with that present in no-tillage system (soybean/sorghum), crop-livestock system (soy/pasture), cultivated coffee, eucalyptus forest and not managed grassland, to form the object of study. Since it is laborious to assess all the physical and chemical parameters that surround the quality of soil and, as the community of fungi and bacteria receive direct influence of these factors, the microbiological study can answer questions about the quality of a native or cultivated system. For this study 10 composite samples were collected within each cropping system on a transect shape, lying 20 meters from each other. The microbial community was evaluated for its density from the quantification of microbial biomass carbon, total carbon, microbial biomass nitrogen and total nitrogen. Once is known that the quantitative assessment would not be enough to express the behavior of microbial community, an analysis of the metabolic potential based on degrading capacity of substrates, enzyme assay and basal soil respiration tests were applied. Quantitative data showed that areas of pasture and no-tillage had similar microbial biomass of the soil under native Cerrado (control) but differ significantly in the degradative capacity of substrates and enzyme activity, showing that crops impress selection under microbiota in these areas.
A conservação da qualidade de solos nativos e cultivados na região do Cerrado, vista do ponto de vista microbiológico, tem sido discutida tanto com foco ecológico quanto produtivo. Neste trabalho, a biota do solo sob Cerrado nativo foi contrastada com aquela presente nos sistemas de cultivo plantio direto (soja/sorgo), integração lavoura-pecuária (soja/braquiária), café, floresta de eucalipto cultivada e pastagem não manejada, formando o objeto de estudo. Posto que é laborioso levantar todos os parâmetros físicos e químicos que circundam a qualidade de um solo e como a comunidade de fungos e bactérias sofre influência direta destes fatores, o estudo microbiológico, exclusivamente, pode responder sobre a qualidade de um sistema nativo ou cultivado. Para este estudo foram coletadas 10 amostras compostas dentro de cada sistema de cultivo em forma de transecto, distando 20 metros entre si. A comunidade microbiológica foi avaliada quanto a sua densidade a partir da quantificação do carbono da biomassa microbiana, do carbono total, do nitrogênio da biomassa e do nitrogênio total. Sabendo que a avaliação quantitativa não seria suficiente para expressar o comportamento da comunidade microbiana, a análise do potencial metabólico baseada nos testes de capacidade degradativa de substratos, teste enzimático e respiração basal do solo, foram aplicadas. Os dados quantitativos mostraram que as áreas de pastagem e plantio direto apresentam uma biomassa microbiana semelhante ao solo sob Cerrado nativo (controle) porém divergem significativamente na capacidade degradativa dos substratos e na atividade enzimática, mostrando que o cultivo imprimiu seleção sobre a microbiota nestas áreas.

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Zaffaroni, Marta. "Modélisation des interactions plant-puceron, en considérant explicitement le rôle des pratiques agricoles : Pêche (Prunus persica) - puceron vert (Myzus persicae) comme cas d'étude An ecophysiological model of plant–pest interactions: the role of nutrient and water availability Maximizing plant production and minimizing environmental impact: comparing agricultural management scenarios with multi criteria decision analysis The role of vectors interference in a shared host-multi vector system." Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0723.

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Les pucerons modifient le développement des plantes et peuvent transmettre des virus, représentant ainsi une menace majeure pour les cultures. Il est possible de réduire la pression exercée par les pucerons sur les plantes et d’améliorer la production agricole en facilitant certains processus écologiques en plus ou en remplacement de l’utilisation de pesticides. Les modèles mathématiques peuvent aider à prédire la direction et la force de ces processus écologiques et ils peuvent révéler l’impact des modes alternatifs de gestion des cultures. La thèse proposée vise à développer des modèles mathématiques basés sur les processus, couplant la physiologie des plantes et la démographie des pucerons, afin de favoriser l’intensification écologique et de réduire l’utilisation des pesticides. Les modèles tiennent compte i) des interactions entre la plante et le puceron, alors que la plupart des modèles de culture ne prennent en compte que l’effet du ravageur sur la plante et non l’inverse, ce qui nuit à la compréhension de la lutte antiparasitaire via les pratiques culturales;et ii) de l’effet des pratiques culturales et du résultat en termes de récolte,questions qui sont généralement absentes dans les modèles écologiques. Je couple tout d’abord un modèle mécaniste de croissance des plantes avec un modèle de population des pucerons, je le calibre pour un système pêche-puceron vert et je l’utilise pour obtenir des informations sur les mécanismes qui sous-tendent la réponse des pucerons à la fertilisation et à l’irrigation. En outre, je développe un modèle épidémiologique qui tient compte explicitement de l’interférence entre deux pucerons vecteurs. J’applique ce modèle pour étudier l’effet de l’interférence inter-spécifique des pucerons dans la propagation des virus des plantes, en tenant compte de l’effet des pratiques agricoles
Aphids alter plant development and can transmit viruses, thus representing a major threat for crops. Aphid pressure on plant can be reduced and crop production can be enhanced by facilitating some ecological processes in addition, or in substitution, to the use of pesticides. Mathematical models can help in predicting the direction and strength of these ecological processes and they can reveal the impact of alternative ways of managing crops. The proposed thesis aims to develop process based mathematical models coupling plant physiology and aphid demography to drive ecological intensification and reduce the use of pesticides. The models consider i) interactions between plant and aphid, while most crop models only consider the effect of the pest on the plant and not vice versa hence impairing insights upon bottom-up pest control via cultural practices; and ii) the effect of cultural practices and the outcome in terms of harvest, issues that are usually absent in ecological models. Therefore, I firstly couple a mechanistic plant growth model with a pest population model, I calibrate it for a peach-green aphid system and I use it to get insights on the mechanisms behind the response of aphids to fertilization and irrigation. Furthermore, I develop an epidemiological model explicitly accounting for the interference between two aphid vectors. I apply the model to explore the effect of inter-specific aphid interference in shaping the spread of plant viruses, considering the effect of agricultural practices

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Nguyen, Thi Tuyet Hanh. "Analyse de cycle de vie de la production bovine : exploration de pratiques et de changements de système pour réduire les impacts environnementaux." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00844398.

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Cette thèse porte sur l'étude des impacts environnementaux de systèmes de production de bovins. Le premier objectif était d'analyser et de comparer les impacts environnementaux de systèmes de production de viande et de lait par analyse de cycle de vie (ACV) attributionnelle. Les effets de pratiques d'atténuation de ces impacts ont été évalués pour les systèmes de production de viande. Le second objectif était un développement méthodologique afin d'explorer les conséquences possibles d'une préférence accrue pour un lait produit à base d'herbe, par ACV conséquentielle. Dans un système de production de viande par le troupeau allaitant, le méthane entérique a été le principal contributeur à l'impact changement climatique, et la production de l'herbe a été la principale contributrice aux autres impacts (demande énergétique cumulée, eutrophisation, acidification, occupation du sol). L'atelier naisseur (vaches allaitantes et leurs veaux, génisses) a contribué de manière majeure aux impacts du système allaitant dans son ensemble. La pratique d'atténuation la plus efficace pour le système a été la diminution de l'âge au vêlage de 3 à 2 ans. L'utilisation de lipides riches en acides gras oméga-3 dans le régime a très peu affecté les impacts du système. L'application simultanée de plusieurs pratiques d'atténuation compatibles entre elles réduit sensiblement les impacts. L'application de pratiques telles que la réduction du gaspillage d'herbe, l'engraissement des génisses non utilisées pour le renouvellement et la diminution de l'âge au vêlage réduisent l'occupation du sol. Un usage alternatif des terres libérées tel que la plantation de forêt pour séquestrer du carbone dans la biomasse semble prometteur. L'étude de systèmes de production de lait a été centrée sur les comparaisons de systèmes à base d'herbe ou d'ensilage de maïs, d'une race spécialisée (Holstein) ou mixte (Normande) et sur l'effet du niveau de production laitière par ACV attributionnelle. Quelle que soit la méthode d'attribution des impacts aux co-produits, les impacts par kg de lait ont été plus faibles pour les systèmes à base d'ensilage de maïs et pour les Holstein, sauf pour l'eutrophisation. L'accroissement de la production de lait par vache grâce à une consommation d'énergie accrue et au vêlage à 2 ans a permis de réduire les impacts du lait et de son co-produit viande. Les conséquences de la conversion d'une exploitation laitière utilisant beaucoup de maïs ensilage vers une exploitation utilisant de l'herbe comme unique source de fourrage pour répondre à une demande de lait produit à base d'herbe en France ont été évaluées par ACV conséquentielle. Cette conversion entraîne des changements notables de l'utilisation des sols en dehors de l'exploitation, et donc un fort accroissement des impacts du système dans son ensemble et du lait produit.

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Thull, Jean-Paul. "Management of stock effluent spillage from trucks in New Zealand." Lincoln University, 1999. http://hdl.handle.net/10182/778.

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The key objective of this multi-disciplinary research was to seek for feasible solutions to avoid effluent from livestock trucks spilling onto roads. Stock effluent spillage mainly poses road safety hazards and environmental damage, and also causes offence to road users and tourists. This task required reviewing previous institutional actions, assessing the power of the existing legislation, and evaluating the interests and attitudes of the stakeholder groups involved in the overall livestock supply chain. It was also necessary to consider politics, administration, public policy and economics, gaining the willing cooperation and confidence of the stakeholder groups through application of 'Soft Systems Methodology' (SSM). A key component was the creation of a 13 minute video and its associated brochure as a primary tool for a stakeholder educational awareness programme. It was necessary to analyse the complex relationships between livestock preparation prior to transport; effluent produced in-transit; and end product quality factors. Detailed information pertaining to the nature of livestock shipments by truck in the South Island of New Zealand had to be collected and verified. All the above information were fed into the calculation of an ideal network of in-transit effluent discharge sites on State Highways in the South Island of New Zealand. Assuming the adoption of best practice throughout the supply chain, it was possible to recommend sustainable solutions. The problem is amenable to solution. Adoption of a strong Industry Code of Practice, coupled with the construction of a strategic network of dump sites will enable the industry to avoid the heavy-handed legal consequences of allowing the status quo to continue.

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Masere, Tirivashe Phillip. "The applicability of the agricultural production systems simulator (APSIM) model to decision-making in small-scale, resource-constrained farming systems : a case study in the Lower Gweru Communal area, Zimbabwe." Thesis, 2011. http://hdl.handle.net/10413/8734.

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Small-scale farmers rarely get enough yields to sustain themselves to the next harvest. Most of these farmers are located in marginal areas with poor soils and in semi-arid areas which receive little rainfall yet the farmers practice rainfed agriculture. A number of reasons can be attributed to the low yields characterizing these farms. Lack of relevant knowledge for decision-making and climate change are among the major reasons for poor yields. Whilst there is not much the small-scale farmers can do to influence climate, they can at least make informed decisions to improve their yields. The information necessary for agricultural decision-making include the climate forecast information and information about performance of new technologies be it fertilisers, varieties or other practices. The study aimed to answer the primary research question: What is the applicability of the APSIM model in decision-making by small-scale resource constrained farmers? This question was supported by secondary research questions namely: - How useful is the APSIM model in small-scale farmers' adaptation to future climate change? - What are the current farming systems of Lower Gweru farmers with regards to maize production? - What are farmers' perceptions of climate change and what changes have they noticed in the last 10 years? - How do small-scale farmers make crop management decisions? Data was gathered through five methods namely, Focus Group Discussions, resource allocation mapping technique, APSIM simulations, on-farm experimentation, and semi-structured interviews. Data was collected from a group of 30 small-scale farmers of Lower Gweru Communal area. The study concentrated on maize production due to the fact that it is the staple food and was grown by all farmers. All the farmers perceived climate to be changing. The changes noted included late start of the rain season, early cessation of rain season and temperature extremes. The majority of farmers highlighted that they were using local indicators to make decisions about climate or to forecast the nature of the coming season before they were exposed to SCF and APSIM. The data gathered from three selected resource allocation maps were used to run the APSIM model. For which farmers were convinced that the model was credible in yield prediction based on the simulated results which reasonably compared to observed yields. The what if questions raised by farmers during the discussions were also assessed and this further increased the farmers' confidence with the model, as they viewed it as a planning and guiding tool before one can actually commit resources. The semi-structured interviews showed that most farmers will continue to use the model outputs in their decision-making. The reasons being that it was a good planning and budgeting tool, it is cheaper and faster since one can assess a lot of options in a short time and would then decide on which options are viable in a given season. The few farmers who said they would not use the model or its outputs in decision-making cited reasons including lack of a computer to install the model and that it was complex for them. Semi-structured interviews confirmed the data collected in resource allocation mapping, focused group discussions and APSIM sessions.
Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

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(8071979), Asmaa H. Morsi. "Optimizing Controlled-Release Fertilizer for Lettuce and Mizuna Grown on the International Space Station." Thesis, 2019.

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Astronaut diets on the International Space Station (ISS) depend on resupplied packaged food. However, missions to Mars of 3-5 years will not accommodate re-supply. In addition, many human macro and micronutrients degrade during long-term storage. Thus, growing nutritional plants aboard ISS is essential for providing astronauts with fresh, healthy produce. NASA is usingan experimental vegetable- production unit called VEGGIE to grow fresh salad crops aboard ISS to provide astronauts with healthy diets. VEGGIE is a small plant-growth chamber designed as a garden for astronauts that is low in mass and has a low power requirement. Veggie is equipped with light-emitting diodes (LEDs) but is exposed to the ISS cabin environment. Plants are grown with roots in a baked-ceramic substrate (arcillite) incorporating controlled-release fertilizer (Nutricote) and wicks delivering water by capillary action from a reservoir.

The fertilizerprills release nutrients into arcillite slowly over time. Different controlled-release types have the same amount of fertilizer but release it over different time periods. The Purdue Mitchell lab in collaboration with NASA is testing growth of salad crops within VEGGIE analogs under ISS-like environments in a growth chamber. Specifically, we are evaluating effects of different controlled-release fertilizer treatments as well as different substrate particle sizeson “cut-and-come-again” harvest scenarios, comparing productivity and quality of Lettuce as well as anAsian salad crop called Mizuna.

SS environments being mimicked include temperature: 24/21°C D/N, CO2: 2800 PPM D/N, RH: 45-50% D/N, and photoperiod: 16hours.Arcillitemedium contained one oftwo different fertilizer mixes: 7.5g18-6-8 T 70 + 7.5g 18-6-8 T100, or 7.5g18-6-8 T70 +7.5g 18-6-8 T180fertilizer/liter medium. LED Light treatment provides atotal PPFDof 330µmol m--2s-1 PAR; with 270µmol m--2s-1Red(R), 30µmol m--2s-1Blue (B), and 30µmol m--2s-1Green (G). Plants are grown under those conditions for 8 weeks, and harvested three times at 28, 42, and 56 days from planting. At each harvest, yield parameters as well as tissue mineral content have been measured for optimum fertilizer treatment selection.

Lettuce and Mizuna plants grown in a mix of 100% fine substrate particles (Profile) and fertilizer treatment of 50% T100:50%T70 had the higher yield as well as nitrogen contentcompared to those grown in 50%T180:50%T70. Growing mizuna plants in 100% profile resulted in higher shoot fresh weight; although no significant differences occurred for shoot dry weight. In addition, there was no significant interaction between substrate and fertilizer, which is reported by other research as one of the advantages of using controlled-release fertilizer

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