Dissertations / Theses on the topic 'Polyculture'
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Rivera, Tina M. "Competitive performance in an apple berry polyculture /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486546889381254.
Full textLiang, Yan. "Reclamation of wastewater for polyculture of freshwater fish." HKBU Institutional Repository, 1997. http://repository.hkbu.edu.hk/etd_ra/137.
Full textCook, Kenneth Arlen. "A Feasibility Study of Penaeid Shrimp and Tilapia in Tank Polyculture." NSUWorks, 1994. http://nsuworks.nova.edu/occ_stuetd/350.
Full textSTROLIGO, CONRADO CHERMUT. "POLYCULTURE IN NOVA FRIBURGO, RJ: EVOLUTION PROCESS AND NATURE-SOCIETY RELATIONS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=27771@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Como se observa na história de Nova Friburgo-RJ, desde o tratado firmado entre Dom João VI e o empresário suíço Nicolau Gachet, em 1818, para a implantação da colônia, o caráter produtivo de alimentos para a metrópole do Rio de Janeiro estava prescrito. Porém, após a chegada dos primeiros imigrantes suíços em 1819, devido a problemas de adaptação cultural, econômicos e ambientais, os objetivos iniciais da colônia foram substituídos pela necessidade de sobrevivência dos colonos, o que favoreceu a miscigenação cultural entre os mesmos e lusos, e ainda, indígenas e afro-brasileiros, favorecendo a formação de uma agricultura de caráter policultural. No decorrer de seus quase dois séculos de existência, o município presenciou a produção de alimentos diversificados no chamado meio rural, quanto no seu centro urbano, onde, ainda encontram-se presentes cultivos com fins de parcial subsistência em quintais produtivos, mesmo que de modo pulverizado na paisagem friburguense. No presente trabalho serão rastreadas as características comuns entre os cultivos dos entrevistados, sendo quatro presentes no distrito-sede e dois em distritos rurais de Nova Friburgo, a fim de analisar sua relação com o processo histórico, documentado, de formação da agricultura policultural de subsistência no município. Todos os manejos possuem caráter biodiverso e policultural na produção de alimentos sem o uso do fogo com fins de fertilização de solo e nenhum tipo de agroquímico. Portanto, este trabalho visa investigar a relação destes espaços produtivos, com as práticas agrícolas historicamente evidenciadas no município, a fim de verificar a potencial existência de vínculo cultural entre os casos do passado e do presente. E é neste contexto entre o atual e o pretérito, o novo e o velho, o interno e o externo que se dá a presente pesquisa.
As noted in the history of Nova Friburgo-RJ since it s creation through the treaty between Dom João VI and the Swiss businessman Nicholas Gachet in 1818 for the implementation of the colony, the food production regarding the supplying Rio de Janeiro city s demand was prescribed. However, after the arrival of the first Swiss immigrants in 1819, due to problems of cultural adaptation, economic and environmental, the initial objectives of the colony were replaced by the need for survival of the settlers, which favored the cultural miscegenation between them and Portuguese s, indigenous and afroamericans, favoring the formation of a polycultural character of agriculture. During nearly two centuries of existence, the city witnessed the production of diversified food types in the so-called rural areas and in its urban center, where there are still present crops with partial subsistence purposes in productive backyards, notwithstanding they are pulverized in Nova Friburgo s landscape. In this work we will seek to analise the common characteristics between the crops of the enquired people, four of those living in the urban district and two in rural districts of Nova Friburgo, in order to analyze its relationship with the documented historical process, of polycultural agriculture subsistence emergence in the city. All managements have biodiverse character and polycultural in food production without the use of fire for fertilizing the soil neither of agrochemicals. Therefore, this paper aims to investigate the relationship of these productive areas, with agricultural practices historically evidenced in the municipality in order to verify the potential existence of a cultural link between the cases of the past and present. It is in this context between the present and the past, the new and the old, the internal and the external that the present research is proposed.
Morgan, Derek. "The potential for Gracilaria polyculture at Jacobs Bay Sea Products Pty." Bachelor's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/25769.
Full textAudibert, Martine. "Déterminants de l’efficience technique dans l’agriculture sahélienne : riziculture et polyculture au Mali." Clermont-Ferrand 1, 1997. http://www.theses.fr/1997CLF10002.
Full textWangpen, Prayadt. "The role of shelter in cherax abidus and bidyanus bidyanus polyculture systems." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/2312.
Full textWangpen, Prayadt. "The role of shelter in cherax abidus and bidyanus bidyanus polyculture systems." Curtin University of Technology, Muresk Institute of Agriculture, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15622.
Full textThe variables will take on different levels in a culture system (i.e. a manager will stimulate turbidity, provide artificial feeds, stock different sizes, and supply particular types of shelter) BUT the actual variables themselves (e.g. food, density, light, shelter) are basic to ALL aquatic ecosystems. Other researchers have looked at important factors like density, gender, and light intensity / turbidity in crayfish polysystems - but the issue of habitat complexity and the role of shelter has not been adequately addressed. This thesis will investigate some basic questions about shelter and endeavour to apply them to crayfish polysystems, with the emphasis on marron (C. tenuimanus) and yabbies (C. albidus) because these are the two most commercially important species of crayfish in Western Australia. Importantly, it should be noted that due to the invasive nature of yabbies, and their apparent ability to displace native marron in the wild, findings will be related to yabby-marron competition / displacement where relevant. We need to know many things about shelter: what type is best in a multi-species system? Should the shelter size match the crayfish size? Do marron have different requirements for shelter than yabbies? Does it matter who gets first use of a shelter (i.e. prior residence effect)? Can we learn about crayfish shelter requirements by examining the behaviour / plasticity of crayfish species? If crayfish are stocked with finfish and they retreat into shelter as a predator-avoidance measure, is the complexity important given that their densities will be higher? If densities of crayfish inside shelters are higher in polysystems, will cannibalism be a concern, particularly when conditions are right for moulting? Does visual recognition and / or chemo-detection of a predator affect the shelter usage by marron or yabbies?
Does temperature affect shelter usage behaviour for a burrowing species like yabbies? Shelter is an important factor in the life history of a freshwater crayfish and an understanding of its influence on different species is important for maximising system performance. Crayfish are categorised depending on their ability to construct shelters (i.e. burrows). Yabbies have evolved in systems with fluctuating water quality and many predators and, as such, have learned to burrow (to escape drought and also to escape predators). Marron, on the other hand, are a non-burrowing native crayfish species that have existed with relatively few predators in the South-West. As a result, marron are less capable of modifying their behaviour when confronted with a predator (i.e. low behavioural plasticity). Species with high plasticity, like yabbies, are more capable of adapting to new environments, because they can change their behaviour to increase their chance of survival. Therefore we can expect yabbies and marron to utilize habitats differently and we should compare these behaviours as a basis to developing management strategies. This type of knowledge may also assist with managing the translocation and spread of yabbies in the wild and their displacement of native marron.Within multi-species systems, the physical structure of shelter plays an important role inprotecting crayfish and the perfect shelter would not only provide safety from co-stocked finfish, but also from conspecific cannibalism. Given the different life histories and behaviours, it is probable that both species of crayfish will have different refuge requirements.Over the course of this four-year investigation, trials were conducted in four culture systems (72L aquariums, 300L circular tanks, 80t mesocosm tank, and 720m2 earthen ponds) using marron and yabbies as the species of interest.
Silver perch and Murray cod were chosen as the finfish species of interest as they appear to have the highest aquaculture potential for native freshwater finfish in Australia at the present time. Further, both of these fish have been documented as potential predators of crayfish, resulting in a challenge to understand the role of shelter in minimising the negative effects of fish-crayfish interactions within a polysystem. This study has confirmed that shelter plays a critical role in multi-species system dynamics. In the case of polysystems, it will affect both interspecific and intra-specific interactions, ultimately governing production and profitability, along with the other, previously defined factors. This means that the manager of a polysystem can influenceproductivity by understanding: a) the behavioural characteristics and biology of the crayfish; b) the feeding biology of the finfish; and c) the system variables (both biotic and abiotic) that will affect the overall well being of the fish and crayfish. In the case ofshelter, the manager should understand the available shelter types, the appropriatedensities, the importance of matching complexity to the crayfish size, and the prior residence effect when choosing a timing strategy for stocking and harvesting. Prior residence increased resource holding potential for both marron and yabbies in the short term. In fact, prior residence was a stronger determinant of successful sheltering than crayfish gender or species. However, in longer-term trials the physical size of the crayfish (larger animals evicted smaller animals) and reproductive status (berried females were successful at evicting all other crayfish) were more important factors in determining successful shelter acquisition, although the temporal variations (i.e. growth and release of young) complicate the issue.
When stocking crayfish of different sizes, and in polysystems, the correct size of shelter becomes critical, as smaller individuals will be forced to leave over-sized shelter and locate a shelter commensurate with their own body size to avoid predators. This is relevant to crayfish nurseries where complex habitat is paramount for juvenile cohorts that display variation in sizes and gender. The expansion of crayfish polyculture holds considerable promise; however, furtherinvestigations are required into shelter complexity within floating fish cages, shelter types and arrangement of shelters within ponds (for increased production and ease-of-harvesting), potential of yabbies in polyculture (comparison of monosex and hybrid strains), and the impact of shelter on escape behaviour of marron in a polysystem.
Danechvar-Kakhi, Mahmoud. "L'intraconsommation de céréales pour l'alimentation animale dans les exploitations de polyculture-élevage françaises." Paris 1, 1989. http://www.theses.fr/1989PA010027.
Full textLuong, Cong trung. "Polyculture crevette Litopenaeus stylirostris (Stimpson, 1974) et poisson Siganus lineatus (Valenciennes, 1835) : faisabilité technique et effets sur le fonctionnement écologique des bassins d'élevage de crevettes." Thesis, Nouvelle Calédonie, 2014. http://www.theses.fr/2014NCAL0059/document.
Full textBlue shrimp Litopenaeus stylirostris farming is a major and profitable activity of aquaculture industryin New Caledonia. However, it is facing two seasonal bacterial diseases, which decrease rearedshrimp yield and threaten the sustainability of the aquaculture development. As reported by theliterature, polyculture with fish would have the potential to decrease the impact of these kind ofdiseases, prevent the deterioration of the environment and to increase the production of the ponds. Thefeasibility of L. stylirostris and Siganus lineatus polyculture in earthen ponds was carried out in thisstudy. The main objectives were 1) to estimate the adaptive capacity and growth performance of S.lineatus, and the environmental variations in a closed culture system, 2) to estimate the technicalfeasibility of L. stylirostris and S. lineatus polyculture, and 3) to estimate the effects of L. stylirostrisand S. lineatus polyculture on zootechnical performances and pond ecology in comparison withmonoculture of these species.To answer to the first objective, Siganus lineatus (5.7g) was stocked at 7, 14 and 21 fish.m-2 in aclosed culture system. After 8 weeks of culture period, S. lineatus growth performance was similarbetween all densities. S. lineatus could well adapt and grow in a closed system, even at lowtemperature, ca. 20oC and high stocking density, 21 fish.m-2. High stocking density did not havenegative effects on S. lineatus growth performance, but could cause the environmental deteriorationdue to increased nutrient input and accumulated organic wastes in the culture system. Asconsequence, S. lineatus could die when water oxygen depleted to below 2 mg.L-1.To reach the second and the third objective, a second experiment showed that adding S. lineatus (25.5g) to L. stylirostris (2.9 g) culture system (15 shrimp.m-2) at 1.2 and 2.4 fish.m-2 did not affect L.stylirostris zootechnical performance during the first stage of the rearing. S. lineatus gained 100% ofsurvival and similar growth performance in all densities. The polyculture system increased totalcombined production by 47 – 106 % and reduced FCR by 31.6 – 47.7% compared with those inshrimp monoculture. The addition of S. lineatus to the culture system did not have significantlyeffects on the gross primary productivity, the respiration, the nutrient and particulates fluxes at thewater-sediment interface of the pond ecosystem.In a third experiment, using higher stocking biomasses of L. stylirostris (14 g) at 156 g.m-2 in apolyculture with S. lineatus (19 g) (80 g.m-2) and at 237 g.m-2 in shrimp monoculture, we observed ahigh shrimp mortality. Conversely, stocking biomasses of S. lineatus (19 g) at 155 g.m-2 in apolyculture with L. stylirostris (14 g) (81 g.m-2) and at 235 g.m-2 in monoculture resulted in increasesof S. lineatus biomasses. This study showed that polyculture using S. lineatus is able to reduce organicwastes and nutrient release by consumption uneaten feed and retention input nutrients in biomass thatcontribute to limit the impact of the pond ecosystem eutrophication.Results of stable isotope analyses showed that the used pellet feed was not a major carbon source, butwas an important nitrogen source for both L. stylirostris and S. lineatus. Natural biota, includingsediment organic matter and particulate organic matter, was a main carbon source and represented asa secondary nitrogen source for both species.It may be concluded that S. lineatus is a suitable candidate for commercial culture in bothmonoculture and polyculture with L. stylirostris in earthen pond. Polyculture should be a properapproach that could partly contribute to sustainable development of aquaculture, but needs specificresearch to optimize the trophic status of the reared species
Zarochentseva, O. "Adaptation of methodology calculation relative crowding coefficient for evaluation competition of tree species in polyculture." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/26816.
Full textBougaud, Jean-Marc. "Etude des risques dus au travail agricole dans une ferme de polyculture du nord-jura." Besançon, 1992. http://www.theses.fr/1992BESA3019.
Full textSaha, Nirmal Chandra. "An economic analysis of pond polyculture in Bangladesh : efficiency, comparative returns, and related environmental and poverty issues /." [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17133.pdf.
Full textLazartigues, Angélique. "Pesticides et polyculture d'étang : de l'épandage sur le bassin versant aux résidus dans la chair de poisson." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL073N/document.
Full textDam pond is connected to its watershed. Use of pesticides on watershed may lead to dissipation in the environment Transfer of registered pesticides remains poorly studied. Thus, the main objective of this work was to improve knowledge about the fate of pesticides in polyculture pond, especially contamination of fish flesh. Five sites, each site corresponding to a pond and its watershed, were characterized. They are placed on a gradient of crop proportion ranging from 0% to 85% of the watershed area. The sum of quantified molecules in water ranged from 0.17 to 8.81 µg / L. The biological response of fish, assessed by evaluation of eight biomarkers (EROD, CYP 3A, GST, CAT, SOD, GSH, GPx, and AChE), establish differences between species and sites studied. A study of 14 targeted pesticides was conducted by a multi-residues method in water, sediments and fish flesh. Isoproturon (maximum value 2.69 µg/L) and metazachlor (maximum value 0.54 µg/L) are the main contaminants in water; Trifluralin (0.5 to 13 µg/kg PS) and isoproturon (0.7 to 56.4 µg/kg PS) in sediments. Trifluralin, isoproturon, carbendazim and metazachlor (maximum values of 21, 0.75, 0.13 and 0.2 µg/kg PF, respectively) are quantified in muscle of fish. Low levels observed in fish can be explained by a low potential to bioaccumulate (measured ex-situ for some molecules, between 10-6 and 10-3). However, half-lives in the muscle may be several weeks depending, explaining the possibility to find molecules in fish flesh. Finally, many factors, particularly related to site characteristics (uncontrollable) and management practices (upgradable), influence profile of pesticides in muscle and biological responses of fish
Coquil, Xavier. "Transition des systèmes de polyculture élevage laitiers vers l'autonomie. Une approche par le développement des mondes professionnels." Thesis, Paris, AgroParisTech, 2014. http://www.theses.fr/2014AGPT0005/document.
Full textAgricultural and environmental qualities of autonomous mixed-crop systems are now recognized by research and public policies: their lower consumption of inputs (fertilizers, pesticides, mechanization...), and their recycling of materials between crops and livestock allow these systems to remain productive while minimizing impacts on the environment. However, their public remains confidential: the path of the reduction or abandonment of inputs requires deep changes in ways of working for the farmer. Our research aims to formalize transition from mixed-crop systems mobilizing inputs to autonomy. We analyze how the farmer work and make his work evolve during the transition. We analyze work activity of (i) farmers in 9 mixed-crop dairy farms from the Sustainable Agriculture Network, and of (ii) experimenters of an experimental mixed-crop dairy farm in INRA ASTER-Mirecourt. We mobilize the concept of professional world as an analyzer of the work activity of the farmer and thus we access to a systemic formalization of activity considering the actions, knowledge and tools of the farmer but also the objects on which he acts, the professional standards to which he refers and his values. Thus, we formalize the development of professional worlds according to a non-teleological process, a no-linear and non-incremental development of farmers' experiences rooted in their history and culture. Creativity of farmers in the action has a place in the development of this experience. Instrumental genesis, that is to say, the movement of the action or of the professional standards of the farmer by the use of an artifact, are resources and stimulators of the development: 30 key artifacts (material tools, cognitive tools...) allow farmers to act on animals, crops, economics, employment, balance of matter, forages, equipment, observations, potential, productivity, socio-professional networks, work and sales during the transition to mixed-crop farming. This development is partly autonomous, ie linked to dynamics internal to professional world, and partly social, ie mobilizing professional standards and artifacts of professional networks of the farmer. Analysis of professional worlds of autonomous mixed-crop farmers reveals original management of crops, animals and even of crop/livestock interactions. This analysis also reveals various work organizations in farms and various wishes of farmers concerning the future. Thus, we describe the singularities of professional worlds in these autonomous systems and we formalize a range of pragmatic concepts, instruments and indicators of management used by autonomous farmers. In the field of ergonomics, this work provides an analytical perspective on the development of professional worlds. In the field of systemic agronomy, it suggests (i) taking into account action’s creativity in the representations of farmers’ action, (ii) a formalization of the acquisition of experience including situations of paradigm shift or the farmer and (iii) a formalization of specific resources of the transition to empower farmers’ development. From an operational point of view, this work suggests exploring ways (i) to extend the public of autonomous mixed-crop farming systems and (ii)!to companion farmers toward autonomous farming, specifying the role of the experimental station of INRA ASTER-Mirecourt.!
Schaller, Noémie. "Modélisation des décisions d'assolement des agriculteurs et de l'organisation spatiale des cultures dans les territoires de polyculture-élevage." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00781098.
Full textBIBANG, NDOUTOUME FLORENTIN. "La polyculture vivriere et son developpement dans le woleu-ntem. Contribution a la geographie rurale du nord gabon." Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR10009.
Full textThe food-producing agriculture in woleu-ntem has some significant assets. But the way the farmers develop them gives very small results. The production does not allow to reach a food self-sufficency. The drift from the land, the producti ve population ageing, the soils chemical poorness, the very little sunshine, the empiricism of the cultivation technics, the rudimentary agricultural equipments the great negligence ofthe administration, the inadequate and precarious infrastructures explain and perpetuate this situation. The future of this branch of activity does not seem very promising, especially since the young people are less and less interested by farm work. A real agricultural development turns out to be essential. It should aim at interesting all the farming population and attract all the young people to the farm work. It would be better to carry it out through the implementation of an overall policy. In that case, the government should quickly concentrate its efforts on making the producers aware of their responsabilities, on the progres sive changing of the land technics, on the marketing organization, on increasing the consumer market, on developing and introducing the necessary infrastructures
Loranger, Jessy. "Prédiction des dommages foliaires causés par les herbivores invertébrés dans une prairie expérimentale à partir des traits des plantes." Mémoire, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/5758.
Full textCosta, Léa Carolina de Oliveira. "Policultivo de camarão Litopenaeus Vannamei e tainha Mugil Platanus em viveiros." reponame:Repositório Institucional da FURG, 2009. http://repositorio.furg.br/handle/1/2195.
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O presente experimento teve como objetivo avaliar o desempenho do camarão Litopenaeus vannamei e da tainha Mugil platanus em sistema de monocultivo e de policultivo. A criação dos organismos foi realizada em viveiros escavados, localizados no Laboratório de Aquacultura Continental da Universidade Federal do Rio Grande. Os viveiros com área aproximada de 200 m² foram previamente tratados com cal virgem e fertilizados com esterco bovino curtido. Os tratamentos, em triplicata, foram: monocultivo de camarão (CM); policultivo de camarão com tainha (P); e monocultivo de tainha (TM). As pós-larvas (PL) de camarão foram estocadas numa densidade de 10 PL m-2 com peso inicial de 0,02 g (± 0,003 g) e as tainhas na densidade de 0,67 peixes m-2, pesando inicialmente 1,67g (± 0,32 g). Peixes e camarões foram alimentados com ração comercial para camarão (38% PB) uma vez por dia. A quantidade de ração ministrada aos camarões inicialmente foi de 20% da biomassa total, decrescendo até 5% no final do experimento. Às tainhas, foi ofertada a quantidade de 5% da sua biomassa, durante todo o experimento. Os parâmetros físico e químicos da água foram registrados diariamente. O experimento teve duração de 79 dias durante o verão de 2007/2008. O acompanhamento do crescimento dos animais foi realizado por biometria semanal. No final do experimento foi verificado o ganho de peso, a taxa de crescimento específico, a conversão alimentar aparente, a sobrevivência e a produção dos animais cultivados, além do fator de condição para as tainhas. Os camarões em monocultivo apresentaram ganho de peso (15,59g), taxa de crescimento específico (8,40 % dia-1), conversão alimentar aparente (0,88), sobrevivência (91%) e produção (1.454 kg ha-1) significativamente maior (p < 0,05) do que no policultivo. As tainhas no policultivo apresentaram ganho de peso (42,72 g) e taxa de crescimento específico (3,99) significativamente maior (p < 0,05) que no monocultivo, enquanto seu fator de condição foi significativamente (p < 0,05) menor no policultivo (1,06). A conversão alimentar aparente das tainhas não apresentou diferenças significativas (p > 0,05) entre o monocultivo (2,50) e o policultivo (2,40). Os parâmetros físicos e químicos não foram significativamente diferentes (p > 0,05) entre os tratamentos adotados, com exceção da transparência que foi maior em viveiro de monocultivo de tainha.
The study objected to evaluate Litopenaeus vannamei (Boone, 1931) shrimp and Mugil platanus (Günther, 1880) mullet performance in monoculture and polyculture system. Culture of organisms was conducted in earthen ponds at Continental Aquaculture Laboratory of Rio Grande University. The ponds, with approximately 200 m², were early treated with lime and organic fertilization. The treatment were: shrimp monoculture (CM); shrimp and mullet polyculture (P); and mullet monoculture (TM), with three replicates. Shrimp post-larvae (PL) was stocked at a rate of 10 PL m-2 with mean initial weight of 0,02 g (± 0,003 g) and mullets were stocked at rate of 0,67 fish m-2, weighing 1,67g (± 0,32 g). The organisms have been fed with commercial meal to shrimp (38%PB) once a day at evening. Meal rate initially given to shrimp was 20% total biomass, it decreased until 5%, at the end of experiment. To mullets, it was given the same rate throughout experiment (5%). The water quality parameters were measured daily. Experiment had duration of 79 days in summer, from December, 5th, 2007 until February, 22th, 2008. Four biometry was done (at days 0, 30, 60 and 79) to accompany animals weight. At end experiment, gain weight, specific growth rate, feed conversion apparent rate, survival rate and yield of organisms cultured were analyzed. To mullets was analyzed too factor condition. Shrimp showed weight gain, specific growth, feed conversion apparent rate, survival rate and yield on monoculture significantly higher than on polyculture (p < 0,05). Mullet showed weight gain and specific growth rate significantly higher on polyculture (p < 0,05), while its condition factor was significantly higher (p < 0,05) on monoculture. There was no significant difference (p > 0,05) between feed conversion apparent rate of mullets among treatments. The water quality parameters had not significantly different between treatments, excepting transparency witch was biggest to mullet’s monoculture. The shrimp’s performance was suppressed in present mullets; it showed better zootechnic performance in monoculture.
Ribeiro, Felipe de Azevedo Silva [UNESP]. "Sistemas de criação para o Acará-bandeira Pterophyllum scalare." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/86704.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Esse trabalho objetivou comparar o desempenho produtivo de acarás bandeira criados nos sistemas de criação em aquários e em viveiros escavados dentro de estufa plástica com e sem policultivo com camarão-da-amazônia em duas densidade de estocagem, 1,6 e 3,2 peixes/10 L. Utilizou-se um DIC, em esquema fatorial 3x2, com 4 repetições. Os peixes dos tratamentos viveiro em monocultivo e em policultivo apresentaram mais que o dobro de ganho de peso, menor consumo de ração, melhor conversão alimentar, maior comprimento padrão e uniformidade do lote em relação aos peixes mantidos em aquários. A produção em aquários e em monocultivo apresentaram diferença na sobrevivência. O aumento da densidade influenciou negativamente o ganho de peso e o fator de condição. A menor densidade apresentou médias de comprimento padrão maiores. O consumo de ração, a conversão alimentar, a uniformidade do lote e a sobrevivência não foram afetada pela densidade. A biomassa não apresentou diferença entre as densidades nos aquários e aumentou com a densidade nos tratamentos mono e policultivo. O peso médio e a sobrevivência final dos camarões foram 1,66g e 84,4%, respectivamente. A análise de custos mostrou valores semelhantes para os sistemas semi-intensivos e inviabilidade para o sistema intensivo. Conclui-se que a produção em viveiros escavados, com ou sem policultivo, é mais eficiente e mais rentável que a produção em aquários.
The present study aimed to compare three production systems for freshwater angelfish: intensive indoor aquarium, semi-intensive greenhoused earth pond (monoculture) and greenhoused earth pond in polyculture with amazon river prawn. It was tested two stock densities: 1,6 and 3,2 fish/10 L. The experimental design was entirely randomized, in 3x2 factorial scheme, with four replicates. Water parameters were adequate for species development. Fish from monoculture and polyculture ponds showed over twice weight gain, lower food consumption, better food conversion rate, bigger standard length and group uniformity than the fish maintained in aquariums. Differences in survivors were observed only between aquarium and monoculture pond. The stock density increase reduced the weight gain and body condition. The lower density showed better means of standard length. Food consumption, food conversion rate group uniformity and survivor showed no difference between the densities. The interaction analysis for biomass was statistical significance, showing no difference between the densities inside aquarium and increasing with density within mono and polyculture ponds. The mean final weight and survivor of amazon river prawns were 1,66g e 84,4%, respectively. Cost analysis showed similar values for semi-intensive systems and no viability for aquarium system. It’s concluded that the production under earth pond, regardless of mono or polyculture system, is more efficient and profitable than indoor aquariums system.
Mira, Sébastian. "Caractérisation et analyse prospective de la contribution de l'effet rhizosphère aux performances du blé (Triticum aestivum) en contexte de polyculture-élevage." Electronic Thesis or Diss., Rennes, Agrocampus Ouest, 2023. http://www.theses.fr/2023NSARD101.
Full textFaced with societal and environmental challenges and loss of biodiversity, the redesign of cropping systems mobilizing ecological interactions instead of synthetic inputs is crucial to develop. The soil-plant interface influenced by root activities is of major interest because it harbors a diversity of processes involved in plant nutrition and health. However, the rhizosphere effect induced by plants is very dynamic, and influenced not only by soil type or crop species but also by agricultural practices. In an approach combining experimentation and statistical modeling by structural equations, indicators of rhizosphere functioning in wheat (Triticum aestivum var Absalon) were developped.The applied methodology allowed to put forward synergistic effects of crop diversification during the succession with reduced tillage in order to promote the rhizosphere effect. Finally, we highlighted a common scheme of causal structure between controlled conditions and the field by structural equation modeling that pave the way for further development of rhizosphere indicators. In conclusion, this thesis work carried out in collaboration with the members of three cooperatives opens perspectives for the design and evaluation of low-input agroecological cropping systems
Naim, Sidrotun. "Growth, Vibriosis, and Streptococcosis Management in Shrimp-Tilapia Polyculture Systems, and the Role of Quorum Sensing Gene cqsS in Vibrio harveyi Virulence." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/268595.
Full textRibeiro, Felipe de Azevedo Silva. "Sistemas de criação para o Acará-bandeira Pterophyllum scalare /." Jaboticabal : [s.n.], 2007. http://hdl.handle.net/11449/86704.
Full textBanca: Manuel Vazquez Vidal Júnior
Banca: Maria Inez Espagnoli Geraldo Martins
Resumo: Esse trabalho objetivou comparar o desempenho produtivo de acarás bandeira criados nos sistemas de criação em aquários e em viveiros escavados dentro de estufa plástica com e sem policultivo com camarão-da-amazônia em duas densidade de estocagem, 1,6 e 3,2 peixes/10 L. Utilizou-se um DIC, em esquema fatorial 3x2, com 4 repetições. Os peixes dos tratamentos viveiro em monocultivo e em policultivo apresentaram mais que o dobro de ganho de peso, menor consumo de ração, melhor conversão alimentar, maior comprimento padrão e uniformidade do lote em relação aos peixes mantidos em aquários. A produção em aquários e em monocultivo apresentaram diferença na sobrevivência. O aumento da densidade influenciou negativamente o ganho de peso e o fator de condição. A menor densidade apresentou médias de comprimento padrão maiores. O consumo de ração, a conversão alimentar, a uniformidade do lote e a sobrevivência não foram afetada pela densidade. A biomassa não apresentou diferença entre as densidades nos aquários e aumentou com a densidade nos tratamentos mono e policultivo. O peso médio e a sobrevivência final dos camarões foram 1,66g e 84,4%, respectivamente. A análise de custos mostrou valores semelhantes para os sistemas semi-intensivos e inviabilidade para o sistema intensivo. Conclui-se que a produção em viveiros escavados, com ou sem policultivo, é mais eficiente e mais rentável que a produção em aquários.
Abstract: The present study aimed to compare three production systems for freshwater angelfish: intensive indoor aquarium, semi-intensive greenhoused earth pond (monoculture) and greenhoused earth pond in polyculture with amazon river prawn. It was tested two stock densities: 1,6 and 3,2 fish/10 L. The experimental design was entirely randomized, in 3x2 factorial scheme, with four replicates. Water parameters were adequate for species development. Fish from monoculture and polyculture ponds showed over twice weight gain, lower food consumption, better food conversion rate, bigger standard length and group uniformity than the fish maintained in aquariums. Differences in survivors were observed only between aquarium and monoculture pond. The stock density increase reduced the weight gain and body condition. The lower density showed better means of standard length. Food consumption, food conversion rate group uniformity and survivor showed no difference between the densities. The interaction analysis for biomass was statistical significance, showing no difference between the densities inside aquarium and increasing with density within mono and polyculture ponds. The mean final weight and survivor of amazon river prawns were 1,66g e 84,4%, respectively. Cost analysis showed similar values for semi-intensive systems and no viability for aquarium system. It's concluded that the production under earth pond, regardless of mono or polyculture system, is more efficient and profitable than indoor aquariums system.
Mestre
Ryschawy, Julie. "Eclairer les conditions de maintien d'exploitations de polyculture-élevage durables en zone défavorisée simple européenne. Une étude de cas dans les Coteaux de Gascogne." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0112/document.
Full textMixed crop-livestock farms are again attracting worldwide interest, as they are considered to be a good way to limit environmental problems while allowing a productive and economically viable agriculture. The incentives of the Common Agricultural Policy and decreasing workforce availability nevertheless marginalized these farms in Europe. This thesis aims at understanding the conditions for a survival of sustainable mixed crop-livestock farms. A partnership process with farmers, mayors and technical advisers has been led in a French less favoured area, the Coteaux de Gascogne. Our work has shown that even if a wide variability existed between farms, local mixed crop-livestock farming was a good trade-off compared to farm specialization concerning an environmental and economic sustainability. An analysis of farm past trajectories allowed us to enlighten four “paths to last” in mixed crop-livestock farming. Two of these ones appeared to be suitable paths to maintain mixed crop-livestock farms in a uncertain context: “maximizing autonomy” and “diversification of production units”. On the basis of these two types of trajectories, we have co-constructed with local actors two technical prospective scenarios. In line with the type “maximizing autonomy”, forage legume intercropping could enable to autonomously feed the bovine herd while maintaining soil fertility. In line with the type “diversification of production units”, fattening heifers would allow a commercialization through short circuit. These scenarios have been adapted and then simulated on local farms. This type of approach allowed to i) strongly involve local actors through collective meetings and ii) an original future study based on a retrospective study integrating long time changes
Thiery, Eglantine. "Contribution des systèmes de polyculture-élevage à la transition agroécologique : approche par modélisation des coopérations entre exploitations en région Bourgogne-Franche-Comté et Rhône-Alpes." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC077.
Full textFrom the second half of the 20th century onwards, the continuous specialization of agricultural holdings and production basins led to numerous biogeochemical and economic imbalances (nutrient cycles opening, dependence on protein-rich raw materials for animal feed, etc.). The implementation of cooperation to promote crop-livestock interactions on the scale of several farms appears to be an alternative to optimize the use and preservation of resources on a specific territory. Our study was carried out as part of the POEETE project (Crop-Livestock on a Farm and Territory scale) PSDR 4 in the Burgundy-Franche-Comté and former Rhône-Alpes regions. Our objective was to make an economic estimation of the implementation of crop-livestock interactions on the scale of several farms in accordance with agroecology. A first study on the analysis of the transaction costs of four cooperative approaches between farms on crop-livestock interactions highlighted the importance of interpersonal relationships and the specificity of the commodity or production tool exchanged in the cost distribution. The second axis focused on estimating the economic interest of a crop-livestock interaction approach between a field crop farm and a typical livestock farm in straw-manure exchange. This cooperation aimed at improving the fertility of the cultivated soils and reducing the use of synthetic fertilizers. The third axis focused on a short alfalfa hay chain to improve soil fertility, reduce inputs and risks of grain farmers and promote a local protein supply for farmers. We were able to establish a price ranged from 10 to 18 €/t for the purchase/sale of manure and a range of 167-189 €/t for alfalfa hay. In both cases, farmers (stockbreeders and grain farmers) could find an economic interest in the exchange even if it remains moderate. These initial simulations would need to be supplemented with other test cases to observe the effect of these interactions on a wider range of systems and to be able to assess regional supply and demand
Hernandez, Barraza Cesar Arturo. "Analyses of Productivity of Nile Tilapia (Oreochromis niloticus), Red Tilapia (O. niloticus X O. mossambicus) and Pacific White Shrimp (Litopenaeus vannamei) Polyculture in a Recirculating System." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/196044.
Full textAmoussou, Nellya. "Développement d’un outil d’aide à la décision pour le choix d’associations d’espèces piscicoles en aquaculture." Electronic Thesis or Diss., Université de Lorraine, 2022. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2022_0261_AMOUSSOU.pdf.
Full textIn aquaculture, polyculture is an ancient and still widespread farming practice in which several aquatic species can be produced together. It is increasingly considered as a promising option to improve the efficiency and sustainability of aquatic production systems, especially in fish farming. However, polyculture can have both beneficial (e.g. recycling of nutrients from the reared biomass reducing environmental impacts) and detrimental (e.g. interspecific competition leading to animal welfare problems) consequences on fish farming. It is therefore essential to assess its consequences on production and fish welfare to highlight the best polycultures among possible species combinations (candidate polycultures). In this PhD, we propose a decision support tool based on a four-step ranking procedure to assess and rank fish polycultures. This ranking procedure, based on a multi-trait approach, allows the selection of polycultures for aquaculture development. When the polyculture is designed to improve the rearing of a species of interest, the ranking procedure aims successively at (i) selecting traits reflecting species compatibility (survival and traits related to morphology, physiology and behavior), (ii) preparing data from experimental tests in recirculated aquaculture system, polarizing them according to the desired expression of the trait for aquaculture purposes, knowing that the highest growth rate and the lowest stress response are sought, (iii) weighting the results of the assessment of the polyculture, and (iv) synthesizing potentially conflicting results by integrating them, through a multivariate approach, into an index to facilitate ranking of candidate polycultures. The decision support tool can also be applied at the whole species level (i.e. considering all combined species). It is considered as an efficient way to select fish species combinations in aquaculture. However, it remains to be adjusted and adapted to all fish farming systems, in order to make it usable for all aquatic rearing systems
Pérès, Guénola. "Identification et quantification in situ des interactions entre la diversité lombricienne et la macro-bioporosité dans le contexte polyculture breton. Influence sur le fonctionnement hydrique du sol." Phd thesis, Université Rennes 1, 2003. http://tel.archives-ouvertes.fr/tel-00007432.
Full textPeres, Guénola. "Identification et quantification in situ des interactions entre la diversité lombricienne et la macro-bioporosité dans le contexte polyculture breton. Influence sur le fonctionnement hydrique du sol." Rennes 1, 2003. https://tel.archives-ouvertes.fr/tel-00007432.
Full textSadek, Shérif S. "Mise au point de techniques de production de la crevette d'eau douce (macrobachium rosenbergii de Man) en monoculture et polyculture en Égypte : avec approche des critères économiques." Toulouse, INPT, 1998. http://www.theses.fr/1998INPT004A.
Full textPérès, Guénola. "Identification et quantification in situ des interactions entre la diversité lombricienne et la macro-bioporosité dans le contexte polyculture breton, influence sur le fonctionnement hydrique du sol /." Rennes : Éd. des Géosciences Rennes, 2004. http://catalogue.bnf.fr/ark:/12148/cb39955665n.
Full textSneessens, Inès. "La complémentarité entre culture et élevage permet-elle d’améliorer la durabilité des systèmes de production agricole ? : Approche par modélisation appliquée aux systèmes de polyculture-élevage ovin allaitant." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22505/document.
Full textSpecialization of farming systems and territories are not environmental-friendly, moreover those systems are threatened by the expected higher prices of inputs of production. Diversification and integration of crop and livestock at the farming system scale appears to be a valuable way to enhance farming system sustainability. We posit that they must be conditions of integration that permit mixed crop-livestock systems to be more sustainable than specialized systems and that existing methods of mixed crop-livestock systems characterization do not permit identifying those conditions. To test those hypothesis, we designed a whole-farm model – Sheep’n’Crop – that permits simulating contrasted mixed crop-livestock systems and evaluating (i) their sustainability through economic, productive and environmental (MJ, GHG, N balance) indicators and (ii) their energetic efficiency through a DEA production frontier analysis in order to characterize the complementarity that exists between crop and livestock subsystems. Those analyses were run on three contrasted farming system strategies, distinguished by a decreasing possibility of interactions between crop and livestock subsystems: integrated systems, non-integrated systems and virtual diversified systems. Those systems are also characterized by various crop-livestock organizations (% of crops) and lambing’s periods (spring or autumn). The analysis of sustainability indicates that crop-livestock interactions and spring seasonality permit enhancing each performance of sustainability. However, a high percentage of crops makes decrease the MJ consumption and N balance performances. The characterization of mixed crop-livestock systems through their energetic efficiency gains – the complementarity – show that integrated and non-integrated systems are respectively more efficient than virtual diversified systems by +6.4% and +0.4%. Comparing the complementarity index and indicators of sustainability of farming systems, we highlighted the existence of trade-off. Before analyzing and identifying the best trade-off compromise, we recommend completing our results by testing various pedoclimatic and socio-economic context, the effect of scale efficiencies, the effect of livestock intensification and increasing agronomic and technical effects of crop-livestock interactions
Bernard, Jennifer. "Conception de systèmes de production innovants dans une dynamique d'intensification laitière - Cas des exploitations de polyculture-élevage relevant des périmètres de la réforme agraire dans le municipe d'Unaí-MG, Brésil." Phd thesis, Ecole nationale superieure agronomique de montpellier - AGRO M, 2010. http://tel.archives-ouvertes.fr/tel-00592328.
Full textBernard, 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.
Full textDairy 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
Raza, Saqlain. "Essays on complementarity : organizational and market changes in agriculture." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0017/document.
Full textThe main objective of this thesis is to test for complementarity between different economic activities in agriculture. To do this, we have recourse to the two approaches proposed by the literature, i.e. the productivity approach and the adoption approach. First, we review the economics of complementarity and analyze the different empirical models to test for complementarity. Then, we propose three empirical analyses testing these models. The first examine closely the drivers of the branding and labeling strategies from French small agricultural co-operatives, with a focus on the coexistence of both quality signals. The second directly test for complementarity between branding and labeling using the adoption approach, by estimating a multinomal probit. This allow us to separate what is really due to complementarity and what is caused by unobserved heterogeneity. Third, in addition to adoption approach, we test for complementarity using a productivity approach in the mixed farming systems adopted by smallholder farmers in Punjab, Pakistan
Velásquez, Yorcelis Carmelina Cruz. "Study on the locally available aquatic macrophytes as fish feed for rural aquaculture purposes in South America." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2016. http://dx.doi.org/10.18452/17510.
Full textIt is commonly known that aquaculture needs to increase further its net contribution to the total world fish supplies. However, at present almost all farming operations, based on the use of fish feed, are highly dependent on available fishery resources for the production of fish meal, becoming a reducing activity rather than an activity suppling fishery resources. If the aquaculture growth potential is to be maintained, then considerable quantities of nutrient inputs in the form of aquafeeds will have to be available on a sustainable basis. On a long-term the small producers will be unable to depend on commercial aquafeeds based traditionally on fish meal, due to its increased price. Small-scale farmers need an alternative fish feed wherever possible based on the use of non-food grade locally feed resources, which is available in rural areas, is low-cost and is suitable for the proper growth and maintenance of native fish. Aquatic plants are considered important nutritional sources for herbivorous-omnivorous fish. However, the use of plant-derived materials as fish feed ingredient is limited by the presence of wide variety of antinutrients that affect the normal fish growth negatively; so that plants should be processed to reduce the effects of these compounds. Considering these aspects, this study assessed the nutritional potential of aquatic plants available in rural Colombia treated by sun drying and by fermentation and the effect of their use as fish feed on the growth performance of common cultured tropical fish (Piaractus brachypomus and Oreochromis niloticus) fed low fishmeal diets (3%) and until 25% of aquatic plants. The results of this study showed that a feeding exclusively based on aquatic plants is not recommendable; but to combine them with other locally available by-products of agriculture or even with commercial diets might considerably reduce feeding cost and provide to the small-scale farmers the opportunity to compete in local markets.
Xandé, Xavier. "Valorisation d'alimentation non conventionnels par une race locale dans un contexte de système d'élevage alternatif de type polyculture-élevage : exemple de la canne à sucre valorisée par le porc créole de Guadeloupe." Antilles-guyane, 2008. http://www.theses.fr/2008AGUY0220.
Full textThe research work of this thesis 1 aimed at providing the professionals with technical and scientific references on a sustainable and integrated farming system, based on the use of a local breed -the Creole pig- and on local crop -the sugar cane. The first wor has consisted in measuring the nutritive and energy value of the sugar cane products (molasses, ground sugar cane, suga cane juice) on the Creole pig. This study shows that there are great disparitles in the digestive and metabolic use of the nutrients according to the sugar cane form allowance. In fact, the characterization of the ground cane nutritive value must take into accunt its chemical composition but also the interpersonal differences in the feeding behaviour of the animals. The second experiment shows that the growth performance and carcass traits vary highly according to the sugar cane form allowance; the very low performance cbtained with the ground sugar cane are in relation with ils high fibre· content which limits its Ingestibillty and reduces the nutrients and energy digestibility. However the organoleplic and gustative quality of the meat (fresh or processed) on average higher with ground sugar cane fed pigs. The third experiment has not permitted to show the positive effect of molasses on the growth performance of ground sugar cane fed pigs. As a conclusion, this research thesis brings very original information on the possible use of the sugar cane as an energy source to feed the Creole pig, especially ln a mixed farrning system context
Moinard, Victor. "Conséquences de l’introduction de la méthanisation dans une exploitation de polyculture-élevage sur les cycles du carbone et de l’azote. Combinaison de l’expérimentation et de la modélisation à l’échelle de la ferme." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASB049.
Full textThe anaerobic digestion (AD) of animal effluents is strongly developing in France. It produces renewable energy (biogas). Like undigested effluents, the use of anaerobic digestates in the field enables the recycling of nutrients and organic matter in the soil, which decreases the need for synthetic fertilizers and maintains soil organic carbon stocks. However, the treatment and field application of those organic products can also cause greenhouse gas emissions and contaminants. The on-farm AD nfluences those impacts. In order to control them, we need to understand how the co-digestion of animal effluents with imported organic wastes influences C and N cycles at the farm scale. We studied this question with the support of a case study at INRAE in Nouzilly (Centre – Val de Loire, France): a crop and livestock farm where an anaerobic digester treats the cattle effluents together with imported wastes. During the MetaMetha field experiment, we compared N fluxes during a crop rotation that was fertilized with synthetic N fertilizers, undigested cattle slurry and farmyard manure, or digestates issued from their digestion. We found that digestates can substitute synthetic fertilizers, despite the risk of ammonia (NH3) emissions. Earthworms can be negatively impacted just after the application of digestate of slurry, but the input of organic matter induced similar positive impacts after two years. We then evaluated the STICS and SYS-Metha models to simulate the field experiment, and digestate treatment and storage, respectively. Both models were coupled to simulate C and N fluxes at the farm scale. The models showed that when large amounts of digested wastes are imported, AD promotes substitution of synthetic N fertilizers and storage of soil organic C, but also NH3 emissions. The study enabled us to better evaluate the consequences of the on-farm AD and therefore to optimize the sector
Tissier, Mathilde. "Conservation biology of the European hamster (Cricetus cricetus) : nutritional effects of crops on hamsters fitness and evaluation of their antipredatory behavior to upgrade wildlife underpasses." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ022/document.
Full textThe European hamster (Cricetus cricetus), one of the most endangered mammal in Europe, is on the verge of extinction in France. However, we are still lacking information on the causes of its decline and on how to improve its conservation. During my PhD, I therefore investigated for the nutritional effects of crops on hamsters’ fitness. The main results highlight that elevated maize consumption is severely reducing hamsters’ reproduction because of a major deficiency in vitamin B3. Then, I found that crop associations such as wheat-soybean and maize-sunflower are favorable to the species and should be implemented in the Alsace. I also developed an anti-predation tube (APT) that will serve to upgrade wildlife underpasses and ultimately allow to reconnect wild populations. Moreover, behavioral tests presented in this thesis reveal that hamsters display bold behaviors when facing a predator. Nonetheless, they use the APT as a refuge in such cases, which validated its anti-predatory function. Therefore, the APT will now be implemented in wildlife underpasses in the Alsace. Results of this PhD will now benefit the conservation of the species in France and in Europe
Thomine, Eva. "Effet de la diversification spatiale et temporelle des cultures à l’échelle du paysage agricole sur le biocontrôle et les ravageurs de culture." Electronic Thesis or Diss., Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR6032.
Full textLandscape simplification have drastically reduced arthropods biodiversity in agricultural landscapes. Plant diversification has already been proved to be very positive for natural enemies notably through the provision of alternative food sources. At the landscape scale, natural habitats have been proved to be very positive for natural enemies and biocontrol. However, the efficacy of natural areas in enhancing biocontrol is more and more controversial. Additionally, farmers willingness to preserve or increase natural habitats in and around their fields is not systematic. Therefore, I decided during my PhD to assess the effect of increasing landscape plant diversity, by manipulating crops only in space and time, on the presence and the performance of natural enemies. In a first part, I assess the economical and social feasibility of increasing crop richness at a landscape scale. Then, in a second part, four different chapters assess the question of crop diversification in space and time on biocontrol at different scales of study. The first chapter shows a study maid at the laboratory scale, which aim is to assess the effect of crop diversification on the predator Harmonia axyridis, on its development and its predation capacity on four different types of aphids. The movement of the predator, hereafter called spillover, regarding the different food sources available is also assessed. The second chapter shows a similar study but laid at a bigger scale (greenhouse) and assesses the population dynamics, the predation capacity and the spillover of a population of Nesidiocoris tenuis regarding differential crop availability in space and time. The third chapter describes two experiments laid at the field scale which aim is to assess the effect of crop diversity, differing in space and time, on the abundance of naturally occurring pests and natural enemies. Abundances of pests and natural enemies was evaluated as a proxy of biocontrol and spillover between patches of crops was assessed in the polycultural treatment. Finally, the last chapter assessed the effect of crop diversity and crop configuration at the landscape scale on the abundance of aphids and aphidophagous predators (coccinellids, lacewings and spiders). The data were collected in the Hebei Province of China. Results at the laboratory and greenhouse scale show that individuals and populations of natural enemies are highly impacted by the functionality of the plant they are exposed to. Indeed, the natural enemies growth in polyculture was the result of the combined effect of the crops tested separately in monoculture. However, the spillover and the biocontrol were highly stimulated in polyculture, sometimes more than in monoculture. At the field scale, ladybirds spillover was higher in polyculture and populations of pests and natural enemies were strongly correlated in polyculture compare to monoculture. Finally, at the field scale, crop diversity had a positive effect on ladybirds abundance and a negative one on aphids abundance. Additionally, fields of small size increased the presence of lacewings. These results show that increasing crop diversity, and decreasing field size, might help to enhance the presence of natural enemies and increase the biocontrol through promoting the spillover of natural enemies between the different cultivated fields
Capitaine, Mathieu. "Organisation des territoires des exploitations agricoles : impact du recours à des collectifs d'action : la conduite de chantiers de récolte en CUMA." Vandoeuvre-les-Nancy, INPL, 2005. http://docnum.univ-lorraine.fr/public/INPL/2005_CAPITAINE_M.pdf.
Full textThe farm is studied as an entity interacting with the context it finds itself in. Specifically, it is included in other organisations like farmers groups, cooperatives, etc. To meet their own running of activities, those organisations require coordination. Wich have an influence on land use allocations in farms. In order to assess whether these situations create or suppress farmers'ability to manoeuvre, it has been decided to select farming groups: the CUMA (Cooperatives for a common use of farm implements). This work is focused on the study of six CUMAs involved in mixed crop-livestock farming systems within the French Vosges area. Results were derived from data collection based on surveys and harvests processes monitoring. The harvest process is perceived as a collective decision arena, anchored in times (workforce and workload management) and space (the farms territories). The CUMAs' impacts on cropping patterns localisations within the farms' territory are different whether they are related to grass ensilage, maize ensilage or harvest. The use of CUMA does not initiate a substantial modification of the land use patterns described in previously used conceptual models. Maize ensilage does not fully comply with existing models as it does not undergo the building to field distance constraint. CUMAs allow to minimize the importance of spatial constraints by providing usage flexibility and territorial competency. On top of the harvesting process using CUMAs' context, this work is likely to find applicability in the land use coordination sector that is necessary to the implementation of contract-based cropping and to the management of environmental concerns
Lu, Xi. "Polycultural Interactions: Fuzzy Identity." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3784.
Full textRoe, Brett, and b. roe@cqu edu au. "Ecologically Engineered Primary Production in Central Queensland, Australia - Integrated Fish and Crayfish Culture, Constructed Wetlands, Floral Hydroponics, and Industrial Wastewater." Central Queensland University. Sciences, 2005. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20080717.092551.
Full textAndrade, Filho Francisco Cicupira de. "Bicultivo de folhosas consorciadas com beterraba em função de adubação com flor- de-seda e densidades populacionais." Universidade Federal Rural do Semi-Árido, 2012. http://bdtd.ufersa.edu.br:80/tede/handle/tede/158.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
This study aimed to assess the agroeconomic viability of the Bicropping of leafy vegetables intercropped with beet as a function of the fertilization with rooster tree and population densities of the component crops. The study was conducted during the period June to November 2011, at the Experimental Farm 'Rafael Fernandes' of the Universidade Federal Rural do Semi-Árido (UFERSA), located in the district of Alagoinha, 20 km away from the city of Mossoró-RN. The experimental design was a randomized complete block with treatments arranged in a 4 x 4 factorial, with four replications. The treatments consisted of combinations of four amounts of rooster tree incorporated into the soil (6, 19, 32 and 45 t ha-1 on a dry basis) with four population densities combinations of component crops (20C-50B-20A%, 30C-50B-50A%, 40C-50B-40A% and 50C-50B-50A% of the recommended densities in sole crop - RDSC, where C = Coriander, B = Beet and A = Arugula). In the cultures of coriander and arugula, the following characteristics were evaluated: plant height, number of leaves per plant or number of stems per plant, yield of green mass and dry mass of shoots. In beet, evaluations were made for plant height, number of leaves per plant, dry mass of shoot, total yield, commercial yield, root dry mass and classified yield of roots. In the intercropping systems, evaluations were made for the canonical variable, productive efficiency index, gross income, net income, rate of return and profitability index. The best productive performance of coriander (1.57 t ha-1) was obtained in the population density of 40C-50B-40A in the amount of 18.60 t ha-1 of rooster tree added to the soil. Best yield performance of arugula (8.21 t ha-1) was obtained in the population density of 40C-50B- 40A in the amount of 10.26 t ha-1 of rooster tree incorporated into the soil. The highest commercial and total yields (18.41 and 16.97 t ha-1) of beet were gotten in the population density of 40C-50B-40A in the amounts of 27.82 and 27.49 t ha-1 of rooster tree, respectively, added to the soil. Both in the multivariate method as in univariate method were registered significant interactions between the treatment-factors studied. Optimization of economic indicators was obtained in the density of 30C-50B-30A in the amount of rooster tree of 32 t ha-1 or in the density of 20C-50B-20A in the amount of 45 t ha-1of rooster tree incorporated into the soil
Este estudo teve o objetivo de avaliar a viabilidade agroeconômica do bicultivo de folhosas consorciadas com beterraba em função de quantidades de flor-de-seda adicionadas ao solo e diferentes combinações de densidades populacionais das culturas componentes. O estudo foi realizado durante o período de junho a novembro de 2011, na Fazenda Experimental Rafael Fernandes da Universidade Federal Rural do Semi-Árido (UFERSA), localizada no distrito de Alagoinha, distante 20 km da cidade de Mossoró-RN. O delineamento experimental utilizado foi o de blocos completos casualizados, com os tratamentos arranjados em esquema fatorial 4 x 4 com quatro repetições. Os tratamentos resultaram da combinação de quatro quantidades de flor-de-seda incorporadas ao solo (6, 19, 32 e 45 t ha-1 em base seca) com quatro combinações de densidades populacionais das culturas componentes (20C-50B-20R%, 30C-50B-30R%, 40C-50B-40R% e 50C-50B-50R% das densidades recomendadas em cultivo - DPCS, onde B = beterraba, C = coentro e R = rúcula). Nas culturas do coentro e da rúcula, foram avaliadas as seguintes características: altura de plantas, número de folhas por planta ou número de hastes por planta, rendimentos de massa verde e massa seca da parte aérea. Na cultura da beterraba, foram feitas avaliações de altura de plantas, número de folhas por planta, massa seca da parte aérea, produtividade total, produtividade comercial, massa seca de raízes e produtividade classificada de raízes. No consórcio, foram feitas avaliações da variável canônica, índice de eficiência produtiva, renda bruta, renda líquida, taxa de retorno e índice de lucratividade. A melhor performance produtiva do coentro (1,57 t ha-1) foi obtida na densidade populacional de 40C-50B-40R na quantidade de 18,60 t ha-1 de flor-de-seda adicionada ao solo. O melhor desempenho de rendimento de rúcula (8,21 t ha-1) foi obtido na densidade populacional de 40C-50B-40R na quantidade de 10,26 t ha-1 de flor-de-seda incorporada ao solo. As maiores produtividades comercial e total (18,41 e 16,97 t ha-1) de beterraba foram alcançadas na densidade populacional de 40C-50B-40R nas quantidades de 27,82 e 27,49 t ha-1, respectivamente, de flor-de-seda adicionadas ao solo. Tanto no método multivariado quanto no método univariado foram registradas interações significativas entre os fatores-tratamentos estudados. Otimização dos indicadores econômicos foi obtida na densidade de 30C-50B-30R na quantidade de flor-de-seda de 32 t ha-1 ou na densidade de 20C-50B-20R na quantidade de 45 t ha-1 de flor-de-seda incorporada ao solo
Snook, Ann Elizabeth. "Superior utilization of patchy resources : a mechanism of overyielding in polycultures." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65411.
Full textRichardson, Mary. "Polycultures of the mind : organic farmers in Québec and the recovery of agency." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25408/25408.pdf.
Full textNavarrete-Mier, Kléber Francisco. "Impacto de los residuos orgánicos generados por los cultivos marinos en jaulas flotantes: alteración de la producción secundaria." Doctoral thesis, Universidad de Murcia, 2011. http://hdl.handle.net/10803/32053.
Full textThe present thesis involved the study of the organic wastes generated by marine culture of fish floating cages, emphasizing in their effect on the associated secondary producers. Several of the impacts on the environment caused by floating cages fish farms have been previously studied by our research group, in that sense, this work deepen in the understanding of those impacts, and ultimately will allow figuring a holistic modeling of the system.
Picasso, Risso Valentín Daniel. "Diversity, productivity, and stability in perennial polycultures used for grain, forage, and biomass production." [Ames, Iowa : Iowa State University], 2008.
Find full textCulbertson, Thimothy W. "Effects of typical concentrations of nitrogen and phosphorus in agricultural treatment wetlands on polycultures of (Typha latifolia) L. and (Juncus effusus) L. and a test of the N:P ratio as a predictive tool." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2822.
Full textThesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Lee, Jie Mi, and 李家銘. "The Production Economics Analysis of Milkfish Monoculture and Polyculture Farming in Taiwan." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/44878715288444114720.
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