Relevance Of Reduced Tillage Practices On Soil Biological, Chemical And Physical Quality And Ecosystem Services Under Organic Farming Context In Britany

Avoiding or limiting ploughing under organic farming management remains a big challenge for organic farmers. By developing an holistic approach, the aim of this study was to evaluate the impact, under organic farming management, of different tillage techniques on soil biological, physical and chemical quality and ecosystem services. In an experimental site located in Britany (France) four tillage techniques were compared: conventional ploughing (CP), agronomic ploughing (AP), superficial non-inversed tillage (C15) and very superficial non-inversed tillage (C8). Results, obtained during 10 years (from 2003 to 2013), showed a strong temporal variability between years, however some results appeared consistent. Positive impact of reduced tillage on hydraulic conductivity and organic matter content was limited to the 0-5 cm depth. No-inversed tillage (C15, C8) and agronomical ploughing (AP) significantly improved microbial biomass. C8 is the only technique which significantly decreased nematofauna. Earthworm biomass significantly decreased under conventional ploughing (CP) due to the decrease of anecic species while ploughing techniques (CP, LA) preserved total earthworm abundance due to endogeic species. Endogeic species had a negative impact on hydraulic conductivity whereas anecic enhanced the conductivity and Carbon and Phosphorus contents. No-inversed tillage techniques (C8, C15) leaded to a decrease of the crop yield, due to an increase of weeds which increased water and nutritive competition. This study highlighted the interests and limits of no-inversed techniques and agronomical ploughing applied in organic farming management for enhancing soil quality and crop yield

Enquête sur les fractures d'instruments dans différents systèmes d'endodontie mécanisée utilisés en exercice libéral

CLERMONT FD-BCIU Odontol. (631132226) / SudocCLERMONT FD-BCIU-Santé (631132104) / SudocSudocFranceF

SGC Bretagne - Expérimenter et évaluer des systèmes de grandes cultures économes en intrants phytosanitaires (de l’intégré au biologique).

Dans le cadre du projet « SGC Bretagne », trois systèmes de culture innovants, sans culture fourragèrepluriannuelle et conçus pour répondre aux besoins des filières d’élevage, ont été conduits durant 6 anset évalués. La conception de ces trois systèmes s’est appuyée sur le cadre « ESR – Efficience,Substitution, Re-conception» : deux systèmes conventionnels s’appuyaient l’un sur la recherched’efficience dans l’utilisation des produits phytosanitaires, l’autre sur les méthodes de reconception dessystèmes de culture ; le troisième était en agriculture biologique. L’évaluation pluri-critères de cessystèmes de culture met en évidence la possibilité de diminuer le recours aux produits phytosanitairestout en maintenant la rentabilité et sans augmenter la charge de travail. Les systèmes de culture testésne pénalisent pas les marges semi-nettes par rapport à la référence utilisée : elles sont équivalentes oumeilleures. La diminution de l’IFT est proche de l’objectif fixé à -50%, avec une réduction de 44% pourles systèmes ayant recours aux produits phytosanitaires, limitée par la dépendance aux herbicides pourla maîtrise des vivaces en interculture. Un autre résultat de l’expérimentation est que la diversificationdes systèmes de culture limite les variations économiques entre années, avec des compensations quise font d’une culture à l’autre au sein de l’assolement

Mode de travail du sol, ruissellement et propriétés hydrodynamiques sur un dispositif expérimental de l'ouest de la France

Mode de travail du sol, ruissellement et propriétés hydrodynamiques sur un dispositif expérimental de l'ouest de la Franc

Conservation practices modify soil phosphorus sorption properties and the composition of dissolved phosphorus losses during runoff

International audienceIt is well established that shallow tillage (ST) and no-tillage (NT) of cultivated soils can have higher risk of dissolved phosphorus (P) loss during runoff than conventional tillage (CT). However, quantitative descriptors of how differences in tillage practices influence soil P sorption properties and how these properties in turn influence dissolved P loss remain lacking. Moreover, the influence of tillage practices on the forms of dissolved P, particularly molybdate unreactive dissolved P (MUDP), has rarely been investigated. Thus, we simulated runoff using pilot soils that had experienced three tillage practices (CT, ST, and NT) and two types of fertilization (pig and poultry manure) for 20 years. The results indicated that shifting from CT to ST or NT changed the soil’s capacity to bind P and increased Olsen-P, Dyer-P, equilibrium P concentration (EPC0), water soluble P (WSP), and the degree of P saturation (DPSOX). The experiment confirmed that switching from CT to ST or NT could increase P loss during runoff. The increase was evident for the two fertilizations (pig manure and poultry manure) with an amplified effect for the poultry manure modality. Switching from CT to ST or NT increased the loss of MUDP, which again was higher for poultry manure fertilization, for which the percentage of MUDP increased to more than 40% of TDP. Correlations between the risk of dissolved P loss and risk assessment indicators were positive, but DPSOX was opposite predicted results to other indicators, indicating that DPSOX was not suitable for predicting the risk of dissolved P loss. Our results suggest that MUDP should be considered when assessing the risk of dissolved P loss when adopting ST and NT, since MUDP is bioavailable and thus can contribute to the eutrophication of surface water

Persistance des Enterobacteriacae resistantes aux fluoroquinolones et à la ciprofloxacin dans le sol après épandage de fumier de poules

International audienceThis study aimed to evaluate the persistence (i) of two fluoroquinolones, enrofloxacin (ENR) and ciprofloxacin (CIP), and (ii) of CIP-resistant Enterobacteriaceae in soil after poultry manure application. The amounts of ENR and CIP in soil did not significantly change over the 48 day- experimental period. CIP (≤ 30 µg kg-1) was detected in weaker concentrations than ENR (20 to 250 µg kg-1 of soil). The concentration of Enterobacteriaceae (102-103 CFU g-1) did not significantly decrease until Day 36. A total of 145 isolates were identified as belonging to E. coli and to 6 genera. The ciprofloxacin MIC of E. coli reached 32 mg L-1 whereas the other strains of Enterobacteriaceae had a MIC ≤ 0.25 mg L-1. The 71 strains of E. coli were classified in 12 ERIC-PCR genotypes. One genotype, corresponding to a resistant strain, was detected until Day 89. This study showed that enrofloxacin and CIP-resistant E. coli persisted at least 48 and 89 days, respectively, in soil. However, their presence did not increase the MIC of Enterobacteriaceae originating from soil

Persistance des Enterobacteriacae resistantes aux fluoroquinolones et à la ciprofloxacin dans le sol après épandage de fumier de poules

International audienceThis study aimed to evaluate the persistence (i) of two fluoroquinolones, enrofloxacin (ENR) and ciprofloxacin (CIP), and (ii) of CIP-resistant Enterobacteriaceae in soil after poultry manure application. The amounts of ENR and CIP in soil did not significantly change over the 48 day- experimental period. CIP (≤ 30 µg kg-1) was detected in weaker concentrations than ENR (20 to 250 µg kg-1 of soil). The concentration of Enterobacteriaceae (102-103 CFU g-1) did not significantly decrease until Day 36. A total of 145 isolates were identified as belonging to E. coli and to 6 genera. The ciprofloxacin MIC of E. coli reached 32 mg L-1 whereas the other strains of Enterobacteriaceae had a MIC ≤ 0.25 mg L-1. The 71 strains of E. coli were classified in 12 ERIC-PCR genotypes. One genotype, corresponding to a resistant strain, was detected until Day 89. This study showed that enrofloxacin and CIP-resistant E. coli persisted at least 48 and 89 days, respectively, in soil. However, their presence did not increase the MIC of Enterobacteriaceae originating from soil

Projet ANR-EVALUFQVOL : Impact de l’épandage de fumiers de volailles sur les transferts de bactéries et d’antibiotiques vers le milieu aquatique

Date du colloque&nbsp;: 03/2011</p