Effects of cropping practice dynamics on permanent grassland vegetation during the conversion to organic farming

The aim of this work was to identify the impact of farming practices on permanent grassland vegetation during the conversion from conventional to organic farming. We considered functional and species diversities in order to compare the different grassland categories based on the farming practices used over a period of six years - five years before conversion and one year after. We identified three categories of grasslands: those generally cut twice a year, those intensely grazed, and those that were used under diversified practices. We showed that grasslands characterised by cutting and low fertilization level have the highest species richness compared to the other two categories (23.2, 16.9 and 17 species, respectively), and the lowest pastoral index (45.9, 66.8 and 68.6, respectively). These cut paddocks also presented the highest functional diversity (i.e., richness of functional property attributes) for two of the properties studied: means of dispersal and establishment strategy as defined by Grime. Grasslands with diversified practices (grazing, cutting and nitrogen supply) were not characterised by any single or combined functional property attribute, to the contrary of the two other categories. Finally, farming practices alone do not explain all of the differences in vegetation. We therefore hypothesize that, first, the dynamics of permanent grassland vegetation following conversion to organic farming is only initiated by agricultural practices and, second, other key factors such as landscape characteristics affect these dynamics

Strongly Temperature Dependent Sliding Friction for a Superconducting Interface

A sudden drop in mechanical friction, between an adsorbed nitrogen monolayer and a lead substrate, occurs when the lead passes through the superconducting transition temperature. We attribute this effect to a sudden drop at the superconducting transition temperature of the substrate Ohmic heating. The Ohmic heating is due to the electronic screening current that results from the sliding adsorbed film.Comment: Revte

Assessing the agro-environmental sustainability of organic mixed-crop dairy systems on the basis of a multivariate approach

Sustainable development calls upon the farming sector to commit itself to the transmission of natural resources to future generations. The INRA research team of Mirecourt studies the design of environmentally-friendly farming systems. The design of these systems is based on a multitude of objectives, and their evaluation is determined by a wide range of criteria. This work aims at determining the practical conditions for implementing agricultural systems considered to be sustainable from an environmental point of view. Two organic dairy systems considered to be environmentally friendly ex ante have been designed in partnership with the staff of the INRA research team of Mirecourt. A grazing dairy system and a mixed-crop dairy system are being experimentally tested at the system scale. The two systems have environmental and agricultural objectives. They are managed using multi-objective decision rules and are assessed on their biotechnical and practical properties, using a structured multiyear experimental design, completed by a model-based assessment. Assessment is oriented towards progressive and permanent re-designing of the systems in order to increase their environmental sustainability and feasibility at the practical level. Knowledge acquired from the two prototypes will then have to be validated on commercial farms

Coherent Electronic Wave Packet Motion in C-60 Controlled by the Waveform and Polarization of Few-Cycle Laser Fields

Citation: Li, H., Mignolet, B., Wachter, G., Skruszewicz, S., Zherebtsov, S., Sussmann, F., . . . Kling, M. F. (2015). Coherent Electronic Wave Packet Motion in C-60 Controlled by the Waveform and Polarization of Few-Cycle Laser Fields. Physical Review Letters, 114(12), 6. doi:10.1103/PhysRevLett.114.123004Strong laser fields can be used to trigger an ultrafast molecular response that involves electronic excitation and ionization dynamics. Here, we report on the experimental control of the spatial localization of the electronic excitation in the C-60 fullerene exerted by an intense few-cycle (4 fs) pulse at 720 nm. The control is achieved by tailoring the carrier-envelope phase and the polarization of the laser pulse. We find that the maxima and minima of the photoemission-asymmetry parameter along the laser-polarization axis are synchronized with the localization of the coherent electronic wave packet at around the time of ionization.Additional Authors: Tiggesbaumker, J.;Meiwes-Broer, K. H.;Lemell, C.;Burgdorfer, J.;Levine, R. D.;Remacle, F.;Kling, M. F

Taking the steps toward sustainable livestock: our multidisciplinary global farm platform journey

Implications • The Global Farm Platform was conceived and established to explore multidisciplinary strategies for optimising the sustainability of ruminant livestock systems around the world. • International sustainability issues are common, but the solutions are often region-specific; therefore, our farms, situated across all major agroclimatic zones, are a unique resource worldwide. • Each farm is following "steps to sustainable livestock" to improve their production system(s), thereby developing robust metrics to progress economic, environmental and social viability. • The consortium works collaboratively to improve the sustainability of ruminants, which we argue are a vital component of global food systems, delivering both human and planetary health

Taking the steps towards sustainable livestock: our multidisciplinary global farm platform journey

Implications The Global Farm Platform was conceived and established to explore multidisciplinary strategies for optimising the sustainability of ruminant livestock systems around the world. International sustainability issues are common, but the solutions are often region-specific; therefore, our farms, situated across all major agroclimatic zones, are a unique resource worldwide. Each farm is following ?steps to sustainable livestock? to improve their production system(s), thereby developing robust metrics to progress economic, environmental and social viability. The consortium works collaboratively to improve the sustainability of ruminants, which we argue are a vital component of global food systems, delivering both human and planetary health