Grass Growth Profiles in Brittany

For farmers, knowing the local grass growth profile and the possible variations between years is very helpful in managing grazing. Indeed, the comparison with herd needs and anticipated farm cover change allows decisions to be made that will maintain the cover at the desired level. This paper proposes a ten-days grass growth profile corresponding to Brittany’s different conditions of soil, climate and pasture management

Effect of Farm Grass Cover at Turnout on the Grazing Management of Spring Calving Dairy Cows

Early spring grazing is an objective for most Irish dairy farmers. If more grass is included in the diet of the cow in early lactation, the profitability of the farm system can be increased. Post turnout, dairy cow feeding management varies with the amount of farm grass cover (FC) available. Experiments on the consequences of different FC at turnout require large resources and all scenarios cannot be accounted for. Consequently, a decision support system, Pâtur’IN (Delaby et al., this volume), was used to describe the effects of various FC at turnout on grazing management in spring

Flash flood warning at ungauged locations: can proxy data be useful tocalibrate the hydrological model used?

International audienceThe Mediterranean region is subject to flash flood events that lead to many damages and sometimes to fatalities.Because not every little river’s tributaries can be monitored, flash floods occur most often on small ungaugedcatchments with limited available data. In this context, the calibration of the hydrological model used within aflood warning system is a tricky task.The aim of this study is to evaluate the potential benefit of ‘proxy data’ in areas where no classical continuousflow measurements are available. Administrative services for example collect and archive large amounts ofregional and local information over long periods based on observed damages, some of which can be used as proxyindicators for flood occurrences (e.g. infrastructure maintenance, insurance claims,...).To determine if such data could be helpful, a benchmark test is carried out, comparing three cases. In thefirst case the entire streamflow data series is used. In the second case, data from case 1 is degraded: only the dateand value of the flood peak are retained. In the last case, only the date of the flood peak is used. This last caseaims to imitate the case, where only proxy data collected by administrative services are available. The first casecorresponds to the classical gauged basin case, which is used as reference.These 3 cases are carried out using a simple conceptual hydrological model (from the GR model family)and data coming from around 150 catchments located in the South East of France and covering a 10-year period(1997-2007). The performance of simulated runoff is evaluated using contingency statistics (CSI). A split-sampletest is used in order to asses the robustness of the different calibrations.Results indicate that performances decrease from case 1 to case 3, case 2 beeing intermediate. Since themethodology developped for case 3 can be applied at ungauged locations, it seems that obtained alerts canbe very helpful when no classical hydrological data is available to calibrate the hydrological model used inthe flood warning system. This work has been made in the framework of the ongoing RHYTMME project.This project aims at developping a warning system in the south of French Alps, using radar rainfall data(http://rhytmme.cemagref.fr/synopsis)

An examination of the genotyping error detection function of SIMWALK2

This investigation was undertaken to assess the sensitivity and specificity of the genotyping error detection function of the computer program SIMWALK2. We chose to examine chromosome 22, which had 7 microsatellite markers, from a single simulated replicate (330 pedigrees with a pattern of missing genotype data similar to the Framingham families). We created genotype errors at five overall frequencies (0.0, 0.025, 0.050, 0.075, and 0.100) and applied SIMWALK2 to each of these five data sets, respectively assuming that the total error rate (specified in the program), was at each of these same five levels. In this data set, up to an assumed error rate of 10%, only 50% of the Mendelian-consistent mistypings were found under any level of true errors. And since as many as 70% of the errors detected were false-positives, blanking suspect genotypes (at any error probability) will result in a reduction of statistical power due to the concomitant blanking of correctly typed alleles. This work supports the conclusion that allowing for genotyping errors within likelihood calculations during statistical analysis may be preferable to choosing an arbitrary cut-off

Effect of Strategy of Forage Supplementation and of Turnout Date in a Medium Stocking Rate System on the Main Characteristics of Dairy Cows Grazing

Having a stocking rate of 2.9 cows per hectare of grassland (35 ares/cow) in Brittany offers many options for turnout date and forage supplementation strategies. For a farmer, knowing the consequences of the different options during the course of the grazing season makes grazing management decisions easier. As experiments on grazing management require considerable resources and are hardly generalisable, various spring scenarios have been tested using a dynamic decision support system, Pâtur’IN (Delaby et al., this volume)

In situ measurement of the acoustic performance of a full scale tramway low height noise barrier prototype

International audienceThe performance of a full scale low height barrier prototype meant to attenuate tramway noise is measured in situ. The prototype is made of a simple L-shape assembly of pressed wood boards covered on the source side with fibrous absorbing material, and has been set up temporarily in a residential area in the town of Saint-Martin-d'H` eres, near Grenoble, through which a tramway line passes. A series of pass-by measurements were made at a close receiver location corresponding to the typical height of human ears, with and without the device. The tram speed has been measured as well using an auxiliary microphone located very close to the track. A significant variability in pass-by levels has been found between the different trams, even when applying an approximate correction for speed. However it is shown that the barrier provides on average an attenuation of more than 10 dB(A), during the whole pass-by. Spectral analysis of the recorded signals is carried out as well to estimate the barrier insertion loss more accurately. Furthermore, comparisons between measurements and simplistic BEM calculations show that numerical predictions can yield rather good estimates of the actual in situ performance, within a few dB(A)

The effects of railway noise on sleep medication intake: results from the ALPNAP-study

In the 1980s/90s, a number of socio-acoustic surveys and laboratory studies on railway noise effects have observed less reported disturbance/interference with sleep at the same exposure level compared with other modes of transportation. This lower grade of disturbance has received the label "railway bonus", was implemented in noise legislation in a number of European countries and was applied in planning and environmental impact assessments. However, majority of the studies investigating physiological outcomes did not find the bespoke difference. In a telephone survey (N=1643) we investigated the relationship between railway noise and sleep medication intake and the impact of railway noise events on motility parameters during night was assessed with contact-free high resolution actimetry devices. Multiple logistic regression analysis with cubic splines was applied to assess the probability of sleep medication use based on railway sound level and nine covariates. The non-linear exposure-response curve showed a statistically significant leveling off around 60 dB (A), Lden. Age, health status and trauma history were the most important covariates. The results were supported also by a similar analysis based on the indicator "night time noise annoyance". No railway bonus could be observed above 55 dB(A), Lden. In the actimetry study, the slope of rise of train noise events proved to be almost as important a predictor for motility reactions as was the maximum sound pressure level - an observation which confirms similar findings from laboratory experiments and field studies on aircraft noise and sleep disturbance. Legislation using a railway bonus will underestimate the noise impact by about 10 dB (A), Lden under the conditions comparable with those in the survey study. The choice of the noise calculation method may influence the threshold for guideline setting