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There is a widespread consensus about the importance of sustainable agriculture. In France, the Farming Orientation Law of July 1999 has set down a precise procedure for the implementation of sustainable agriculture: the 'contrat ...
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There is a widespread consensus about the importance of sustainable agriculture. In France, the Farming Orientation Law of July 1999 has set down a precise procedure for the implementation of sustainable agriculture: the 'contrat territorial d'exploitation' - or territorial farm contract (TFC). This paper aims to analyse the TFC effectiveness. An analysis has been made of the TFCs signed in the Midi-Pyrenees Region in south-western France, using statistical analysis and qualitative surveys of a sample of farms. The results show that the most valuable effects have been mainly economic. Effects regarding social and environmental aspects were very limited. But from the point of view of an integrated approach, indirect effects of TFCs can be observed on social and environmental aspects. These results are explained, on the one hand, by farmers' motivations guided by economic objectives, and on the other hand, by the dominance of professional farming organizations in the implementation of TFC's procedure. Given these results, two ways of improving the elaboration procedure for TFCs are proposed. Firstly, technical improvements can be made to the diagnostic assessment of farms, and to the choice of actions addressed by the contract. Secondly, organizational improvements can be applied to TFCs elaboration and implementation process, in order to adopt a participatory approach which would involve all rural stakeholders..
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Les conceptions de l'agriculture biologique et les modèles de son développement présentent une grande diversité. L'objectif de cet article est de saisir cette diversité au niveau des exploitations agricoles à travers la noti...
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Les conceptions de l'agriculture biologique et les modèles de son développement présentent une grande diversité. L'objectif de cet article est de saisir cette diversité au niveau des exploitations agricoles à travers la notion de " logique de fonctionnement ", et de montrer par la suite que la durabilité de ces exploitations varie en fonction des logiques poursuivies. Une typologie a été réalisée à partir d'une méthode d'analyse en composantes principales. Elle a permis d'identifier trois grandes logiques de fonctionnement : entrepreneuriale, recherche d'équilibre et modernisation. Ces logiques présentent des différences significatives de durabilité au niveau agro-écologique et économique. Les exploitations poursuivant la logiquemédiane, de recherche d'équilibre, semblent réussir par différents arbitrages à concilier des objectifs divers et aboutir à une meilleure durabilité.
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In French-speaking Africa, the production of cotton experienced a relative success compared to other agricultural activities. Nevertheless, due to the combined effect of successive crises in the world market and inefficient manage...
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In French-speaking Africa, the production of cotton experienced a relative success compared to other agricultural activities. Nevertheless, due to the combined effect of successive crises in the world market and inefficient management practices, theAfrican cotton sector encounters major financial difficulties. In the mid-1980s, the cotton crisis forced the sector to enter into a restructuring process in order to re-establish financial balances with, as a consequence, the progressive disengagementofthe Stale. The restructuring process was subject to a very intense debate between the French cooperation agency, who champions the "integrated-chain" logic, and the World Bank, who supports complete liberalisation. Nowadays, the complete liberalisationof the African cotton sector seems to be inescapable. In this liberalising context, what can be the economic opportunities and the strategies of cotton producers? This paper deals with this question using the case of the Centrafrican producers. Its objective is to analyze farmers' strategies and their evolution in the context of a newly liberalised cotton sector. This study aims at improving the efficiency of measures geared to support and accompany producers in their adaptation process. The methodologyof our research is based on the analysis of the liberalisation process of the Centrafrican cotton sector and on field studies of cotton producers. Results show that, in this uncertain context, farmers try to protect themselves from market risks by developing strategies, that allow them to assume the market stabilisation function, traditionally guaranteed by the State and the cotton integrated-chain mechanisms. As a first option, producers individually take care of this stabilisation function by developing a defensive strategy of diversification of activities. It appears that this strategy has a high social cost and requires a certain number of socio-economic and technical conditions. As a second option, producers collectively provide the stabilisationfunction, by developing an organisational strategy of collective action through producer organisations. In this offensive strategy, the action of producers goes from the simple protection against market risks (mutual and farming stabilisation fund) tothe development of one or several activities in the cotton sector (supply, shelling, etc.).
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This paper offers a theoretical analysis for a renewed approach to farming suitable to the requirements of sustainability and multifunctionality, and provides an empirical example. It first proposes a broader approach to strategic...
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This paper offers a theoretical analysis for a renewed approach to farming suitable to the requirements of sustainability and multifunctionality, and provides an empirical example. It first proposes a broader approach to strategic resources that can be mobilized by farms. These include not only the classic forms of capital (physical, human, and financial) but also natural and social capital. This theoretical framework relies on a resource-based approach. Second, starting from stakeholder theory, the farm is represented as an organization inserted in stakeholder networks and a web of multiple influences acting on the farmers' strategic decisions. Stakeholder theory offers a new light on the farm's borders and on its relations with other non-agricultural participants and actors..
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La filière cotonnière a fait l'objet de débats très intenses entre la logique intégrée défendue par la France et la libéralisation complète soutenue par la Banque mondiale. La libéralisation complète des filières de co...
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La filière cotonnière a fait l'objet de débats très intenses entre la logique intégrée défendue par la France et la libéralisation complète soutenue par la Banque mondiale. La libéralisation complète des filières de coton africaines sembleaujourd'hui inéluctable. Cet article apprécie les stratégies des agriculteurs et leurs peispectives dévolution dans ce contexte de libéralisation des filières. Dans ce contexte d'incertitude, les agriculteurs cherchent à se protéger des risquesen développant des strategies permettant d'assurcr la fonction de stabilisation qui était assurée jusque-là par l'état et les mécanismes de filière intégrée les producteurs assument cette fonction de stabilisation soit individuellement en développant une stratégie défensive de drver sification des activités, soit collectivement en développant une stratégie oiganisationnelle d'action collective dans le cadre d organisations paysannes. Cette demièic stratégie offensive va de la simple protection contre les risques du marché (mutuelle et fonds de stabilisation paysans) jusqu'à l'acquisition d'un ou plusieurs rnétiers de la filière (approvisionnement, égrenage, etc.).
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As is the case for other insects ovipositing on or in resources that are limited in time and/or space, the two-spot ladybird beetle, Adalia bipunctata (L.) produces an oviposition-deterring pheromone (ODP), which is produced by th...
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As is the case for other insects ovipositing on or in resources that are limited in time and/or space, the two-spot ladybird beetle, Adalia bipunctata (L.) produces an oviposition-deterring pheromone (ODP), which is produced by the larval stages. Foraging larvae touch the substrate with their tarsi and the anal disk on the tenth abdominal segment. The aim of this paper was to determine whether the ODP produced by larvae was deposited by the tarsi or the anal disk. Fourth instar larvae either had their anal disk and tarsi, or anal disk, or tarsi coated with a water-soluble mounting medium. Larvae so treated were allowed to walk on filter paper that was subsequently presented to gravid females. The tracks of larvae that had both their tarsi and anal disk masked did not inhibit oviposition. However, the tracks of larvae that had only their tarsi masked significantly inhibited oviposition but those of larvae that had only their anal disk masked did not. It is concluded that the ODP is deposited on the substrate by the anal disk on the tenth abdominal segment of larvae.
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Socio-professional identity of teachers may have an impact on their way of teaching biotechnology. Livestock and crop production teachers have been trained according to the intensive agriculture model. They have been affected by t...
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Socio-professional identity of teachers may have an impact on their way of teaching biotechnology. Livestock and crop production teachers have been trained according to the intensive agriculture model. They have been affected by the emergence of limits to this model; an identity crisis has appeared due to the gap between their disciplinary culture and new social demands. Biotechnology applications have various repercussions in different disciplinary fields, whether in the humanities or in science an technology. To identify the influence of the prevailing culture in various disciplines, a comparative study of opinions (arguments, emotions, behavioural intentions) on various biotechnology applications held among teachers of different disciplinary options has been made in agricultural education in France. In the fields of ethics, human health and the environment, the opinions among teachers in the humanities (economics, modern languages and history/geography) differed significantly from opinions among teachers with scientific and/or technical training (in biology and livestock and crop production). The former expressed more disquiet than the latter. Biology teachers felt less concern about the development of biotechnology applications.
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2E,4E,6E,11Z-Octadecatetraenoic acid was synthesized in a good yield and in a stereospecific manner by coupling a vinylborane compound and ethyl trans-3-iodoacrylate.The trienic system (E,E,E) was obtained by successive use of met...
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2E,4E,6E,11Z-Octadecatetraenoic acid was synthesized in a good yield and in a stereospecific manner by coupling a vinylborane compound and ethyl trans-3-iodoacrylate.The trienic system (E,E,E) was obtained by successive use of metal-catalyzed coupling and hydro-metallation reactions.
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Cet article propose des réflexions théoriques, avec l'appui d un exemple empirique, pour une approche renouvelée de l'exploitation agricole adaptée aux exigences de la durabilité et de la multifonctionnalité de l'agriculture...
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Cet article propose des réflexions théoriques, avec l'appui d un exemple empirique, pour une approche renouvelée de l'exploitation agricole adaptée aux exigences de la durabilité et de la multifonctionnalité de l'agriculture. Nous proposons, premièrement, une approche élargie des ressources stratégiques mobilisables par l'exploitation agricole, en incorporant en plus des capitaux classiques - physique, humain et financier - le capital naturel et le capital social. Ce cadre théorique s'appuie sur l'approche fondée sur les ressources. Deuxièmement, en partant de la théorie des parties prenantes, l'exploitation agricole est représentée en tant qu'organisation insérée dans des réseaux d'acteurs et dans un tissu d'influences multiples agissant sur les décisions stratégiques des agriculteurs. La théorie des parties prenantes permet d'apporter un éclairage sur les frontières de l'exploitation agricole et sur les rapports de l'exploitation agricole aux nouveaux acteurs non agricoles.
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Intraspecific and interspecific predation of eggs is a well documented phenomenon amongst aphidophagous coccinellids. The invasive species Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is known to be a top intraguild pred...
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Intraspecific and interspecific predation of eggs is a well documented phenomenon amongst aphidophagous coccinellids. The invasive species Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is known to be a top intraguild predator and reported to attack the eggs of many coccinellid species both in a laboratory setting and in the wild. A previous laboratory study highlighted that while many species’ eggs were highly palatable to H. axyridis, the eggs of Calvia quatuordecimguttata (Linnaeus) (Coleoptera: Coccinellidae) appeared to be extremely well protected from attack. Here we present the results of behavioural experiments testing the hypothesis that substances on the egg surface are responsible for this protection, and report preliminary results of GC-MS analysis of these compounds. When the coatings of C. quatuordecimguttata eggs were removed using hexane, they became significantly more susceptible to predation by neonate H. axyridis larvae. However, their overall palatability was not affected, in that complete consumption was never or rarely observed. This suggests that the surface compounds are a true indicator of unpalatability in this species. The effect of hexane-washing on already palatable conspecific eggs was also analysed but had no significant effect on the susceptibility of eggs to cannibalism. We conclude that the eggs of at least one European species are effectively protected by surface deterrents from intraguild predation by H. axyridis. This effect might be due to both the diversity and abundance of hydrocarbons present within the egg coating, the presence of alkenes and/or the presence of patches of a red substance on the eggs’ surface, which is thought to belong to the acid group. In conjunction with data on the susceptibility of other immature stages of C. quatuordecimguttata, this finding may indicate a decreased risk of the species falling victim to invasive H. axyridis, despite their coincident habitat ranges.
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