In a review of landscape-scale empirical studies, Fahrig (2017a) found that ecological responses to habitat fragmentation per se (fragmentation independent of habitat amount) were usually non-significant (> 70% of responses) and that 76% of significant relationships were positive, with species abundance, occurrence, richness, and other response variables increasing with habitat fragmentation per se. Fahrig concluded that to date there is no empirical evidence supporting the widespread assumption that a group of small habitat patches generally has lower ecological value than large patches of the same total area. Fletcher et al.(2018) dispute this conclusion, arguing that the literature to date indicates generally negative ecological effects of habitat fragmentation per se. They base their argument largely on extrapolation from patchscale patterns and mechanisms (effects of patch size and isolation, and edge effects) to landscape-scale effects of habitat fragmentation. We argue that such extrapolation is unreliable because: (1) it ignores other mechanisms, especially those acting at landscape scales (e.g., increased habitat diversity, spreading of risk, landscape complementation) that can counteract effects of the documented patch-scale mechanisms; and (2) extrapolation of a small-scale mechanism to a large-scale pattern is not evidence of that pattern but, rather a prediction that must be tested at the larger scale. Such tests were the subject of Fahrig's review. We find no support for Fletcher et al.'s claim that biases in Fahrig's review would alter its conclusions. We encourage further landscape-scale empirical studies of effects of habitat fragmentation per se, and research aimed at uncovering the mechanisms that underlie positive fragmentation effects.

Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish (), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management.

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A study on nitrogenous and phosphorous waste production in European seabass (Dicentrarchus labrax) was carried out in a flow-through land-based farm. The main objectives were (i) to calculate nitrogenous (N) and phosphorous (P) waste production (particulate and dissolved) from in situ measurements for different rearing ponds with specific fish biomasses, fish sizes and flow rates, (ii) to establish nitrogenous and phosphorous waste production budgets, ratios and equations, and (iii) to compare, for the whole farm, in situ measurements to estimate N and P waste production from waste equations. Waste production was manifest by an increase in concentrations of total ammonia nitrogen, total Kjeldhal nitrogen, particulate nitrogen, dissolved phosphorus and total phosphorus concentrations in the outlet water compared to the inlet water for both batches and whole farm. However, no production of nitrite or nitrate was observed. In our budgets, the N and P amounts from biomass gains and wastes were explained by the N and P derived from feed over the range 83.9-105.2 % and 66.5-104.6 % respectively, depending on the fish batch. Values were respectively 103.4 and 87.5 % for the same calculations in the farm. When the whole-farm waste production was calculated from previous equations derived from batches, and then compared with the measured data, the percentages of recovery (estimated by the ratio predicted data/measured data) were 88 and 94 % for total-N and total-P respectively. 0 Ifremer/Elsevier, Paris Fish farm waste I excretion I nitrogenous budget I phosphorous budget ! Dicentrarchus labrax R&urn6-Quantification des rejets azot&s et phosphor&s d'une ferme d'klevage en bassins de bars Dicentrarchus labrax. L'Ctude de la production des dkchets (azote et phosphore) d'une ferme de production de bars (Dicentrarchus labrax) est rkaliske. Cette Ctude k pour objectif (i) de mesurer in situ la production des dkchets azotCs et phosphor& sous forme particulaire et soluble, pour diffkrents bassins d'klevage prksentant des caractkistiques variables en terme de biomasse de Poisson, de taille des poissons, de d&bit de l'eau de renouvellement, (ii) d'ktablir des Cquations de production de dkhets B park des donnees pr&Cdemment acquises, (iii) de comparer, pour l'ensemble des rejets au niveau de la ferme, les rksultats obtenus par des mesures in situ, d'une part, et B l'aide des Cquations, d'autre part. La production de dtchets se traduit par une augmentation des concentrations de l'azote particulaire, de l'azote ammoniacal, de I'azote organique dissous, ainsi que du phosphore particulaire et dissous. Aucune augmentation des nitrates et nitrites n'est observke. L'Ctablissement des budgets d'azote et de phosphore permettent de rendre compte, selon les bassins, du devenir de 88,2 B 105,2 % de I'azote et de 66,2 k 104,6 % du phosphore introduits dans les bassins sous forme de nourriture en granulks. L'Ctude des budgets rCalisCe par les deux mkthodes (mesures in situ et utilisation des kquations) montre que les budgets Ctablis g l'aide des...

To test the effect of the exposure to trichloroethylene (TCE) on renal cell cancer (RCC) risk, a case-control study was performed in the Arve Valley (France), a geographic area with a high frequency and a high degree of such exposure. Cases and controls were selected from various sources: local general practitioners and urologists practicing in the area and physicians (urologists and oncologists) from other hospitals of the region who might treat patients from this area. Blinded telephone interviews with cases and controls were administered by a single trained interviewer using occupational and medical questionnaires. The analysis concerned 86 cases and 316 controls matched for age and gender. Three approaches were developed to assess the link between TCE exposure and RCC: exposure to TCE for at least one job period (minimum 1 year), cumulative dose (number of p.p.m. of TCE per job period multiplied by the number of years in the job period) and the effect of exposure to peaks. Multivariate analysis was performed taking into account potential confounding factors. Allowing for tobacco smoking and Body Mass Index, a significantly 2-fold increased risk was identified for high cumulative doses: odds ratio (OR)=2.16 (1.02-4.60). A dose-response relationship was identified, as was a peak effect; the adjusted OR for highest class of exposure-plus-peak being 2.73 (1.06-7.07). After adjusting for exposure to cutting fluids the ORs, although still high, were not significant because of lack of power. This study suggests an association between exposures to high levels of TCE and increased risk of RCC. Further epidemiological studies are necessary to analyze the effect of lower levels of exposure.

One year after the crash, victims may still be experiencing multiple problems in terms of not only physical health but also of mental health, social life, and environment. Poor outcome may be predicted from both accident-related factors and socioeconomic fragility. Our results are useful in catching the attention of both clinicians and the public administration regarding victims at risk of suffering from important consequences after an accident. If those suffering head injuries are recognized, it would be very important to better consider and treat posttraumatic stress disorder (PTSD) or PCS. Furthermore, subjects from lower socioeconomic backgrounds, with or without lower limb injuries, have numerous difficulties after an accident, notably for returning to work. An objective would be to provide them with more specific support. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

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