1,720,962 research outputs found
AN INDICATOR OF CROPPING SYSTEMS ECONOMIC ROBUSTNESS
No full textIn a context of increasing variability of weather conditions and prices, robustness is becoming a required characteristic of
farming and cropping systems. We propose and test an indicator of cropping systems robustness based on gross margin
variations. The method probably leads to underestimate gross margin variability because of the input data, the indicator
appeared sensitive. However, it allowed to identify the variability of the major variation factors and, above all, to evaluate
ex-ante several alternative cropping systems in a test loops design process. The method will be tested on several arable
cropping systems besides other tools to forecast yields variability
Design of innovative legume-based systems: the case of soybean-based cropping systems in Oise, northern France.
No full textCo-Design to Identify Lack of On-Farm Agronomic References?
No full textA large part of Northern France is targeted by measures for water protection. Within an agricultural water catchment of this area, high nitrate and pesticide concentrations have led local authorities to encourage innovative farming practices through agro-environmental measures in 2007 and 2015. For six years, a group of 23 farmers has been involved in low input farming and benefits from specific advice and sharing experience (regular meetings, field tours...). To go further, they also have asked for our support to consider new technical leverages in order to both lower pollution risks and maintain or improve farm profitability.
As the group has already improved its cropping systems (CS), we have considered i) the reasons why farmers do not use these techniques, except farm machinery availability, is that they need more references, ii) the references that they need are not obvious enough to be identified through a simple survey such as “what do you want /need to know to be able to improve your CS?” Several types of references were considered important for farmers to judge if they can introduce a technique in a given combination of CS and soil: the technique efficiency according to their objective(s), the conditions for which the technique is efficient and feasible, and its potential side effects.
Thus, to select techniques and detect references needed we have proposed to co-design new CS with each farmer based on the second step of the STEPHY approach, initially developed to co-design CS for low pesticide use. To propose all suitable techniques or leverages according to farmers’ objectives, the STEPHY tool was enlarged to other objectives such as reducing nitrates leaching or avoiding resistance development to herbicides in weeds population. To do this, data on suitable techniques were compiled according to the types of references for each potential objective.
In order to consider with each farmer the improvements he could implement, its main objectives were identified and a cropping system x soil type combination to be re-designed was chosen either for its water risk or for its economic importance. If the farmer has not or refused to introduce each proposed technique, then he had to argue the reasons.
The information collected during the interviews with farmers has been expressed as questions such as: “does sunflower introduction need to be combined with mechanical weeding to reduce herbicide use in Rapeseed/ Wheat/ Winter barley/ Pea/ Wheat rotation on a chalky soil?” Those questions have been presented to the farmers’ group as a feedback for complements and validation.
Starting from those questions, the group will have to choose techniques of interest, methods and tool (kind of experiment or survey) to test these techniques, protocols to evaluate their efficiency, their conditions of efficiency and feasibility, and their potential side effects
Precision farming uses typology in arable crop-oriented farms in northern France
Full text linkInternational audienceThe adoption of precision farming techniques (PFTs) has been widely studied targeting specific PFT or farming systems along with the potential benefits of these PFTs in terms of yield or input use. However, few studies have examined how PFTs are adopted and used at the farm level. In this study a preliminary investigation was made of on-farm PFT uses in the Oise region (northern France). Three main PFTs were identified in the area: Global Navigation Satellite Systems (GNSS) guidance, section control, and variable rate (VR) application. For each farm, the use of every PFT was defined by the technical characteristics of the equipment, the field operation(s) concerned, the targeted crop(s), the aim of the use, the PFT adoption drivers, and the perceived impacts by the farmers. These different variables were combined into a typology of PFT uses. The results show that most of the farms combined GNSS guidance for all technical operations and section control, whereas VR application was less common. Section control was largely used by farmers for liquid fertilizers and phytochemical spraying. The typology shows three to five types of use for each PFT, which differ in terms of technique adoption drivers, e.g. reducing on-farm work or adaptation to field morphology. According to literature, economic impacts were found to be the most frequent, however farmers seemed unable to quantify them. Social impacts such as reduced work time and fatigue were also frequent and are becoming the main motivation for using PFT on farms studied. Further research is needed to assess the use trajectories of PFT along with the motivations of each PFT use
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
An Innovative Land Suitability Method to Assess the Potential for the Introduction of a New Crop at a Regional Level
No full textInternational audienceAlthough crop diversification is one of the main strategy of agroecological transition, a major obstacle is the lack of local references regarding new crops. Land suitability methods can provide a rapid screening of crop suitability in a region. However, mainstream methods are mainly based on assessing soil and climate suitability, whereas it is fundamental to know where and how a new crop can be introduced into existing crop rotations and whether this introduction would be profitable. Our method based on recent advances in the characterization of cropping systems at the regional level can be exploited to evaluate: (1) the yield potential of the new crop, (2) the potential of this new crop being successfully introduced into ongoing crop rotations; (3) the economic benefits of such an introduction. The method was tested for the possible introduction of new soybean varieties in northern France. The method developed has relevance beyond the case study. Our method could also be easily adapted to rapidly assess the potential for introducing new crops in cases where there climate database, soil map information and a Land Parcel Identification System are available
- …
