1,326 research outputs found

    Global Governance for Environmentally Sustainable Food Systems: Certified Organics in a North – South and South-South Perspective

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    Challenged to consume with less environmental impact, consumers buy certified organic products to “proxy” environmental governance. The paper explores how far certified organic agriculture is institutionally embedded in Brazil, China, and Egypt. The three case studies illustrate how regulation, including standard-setting and certification processes differ between south and north, in terms of the evolution and nature of certification, as well as stakeholders and agency involved in shaping the regulation. A comparative analysis is presented on south-south differences in this regard along with some possible explanations of these. The paper finally discusses the perspectives in the global success of organic certification and whether it has potential to transform global agriculture towards higher overall levels of sustainability

    Epidemiology and integrated control of Potato Late Blight in Europe

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    Phytophthora infestans, the causal agent of late blight, is a major threat to potato production in northwestern Europe. Before 1980, the worldwide population of P. infestans outside Mexico appeared to be asexual and to consist of a single clonal lineage of A1 mating type characterized by a single genotype. It is widely believed that new strains migrated into Europe in 1976 and that this led to subsequent population changes including the introduction of the A2 mating type. The population characteristics of recently collected isolates in NW Europe show a diverse population including both mating types, sexual reproduction and oospores, although differences are observed between regions. Although it is difficult to find direct evidence that new strains are more aggressive, there are several indications from experiments and field epidemics that the aggressiveness of P. infestans has increased in the past 20 years. The relative importance of the different primary inoculum sources and specific measures for reducing their role, such as covering dumps with plastic and preventing seed tubers from becoming infected, is described for the different regions. In NW Europe, varieties with greater resistance tend not to be grown on a large scale. From the grower’s perspective, the savings in fungicide input that can be achieved with these varieties are not compensated by the higher (perceived) risk of blight. Fungicides play a crucial role in the integrated control of late blight. The spray strategies in NW Europe and a table of the specific attributes of the most important fungicides in Europe are presented. The development and use of decision support systems (DSSs) in NW Europe are described. In The Netherlands, it is estimated that almost 40% of potato growers use recommendations based on commercially available DSS. In the Nordic countries, a new DSS concept with a fixed 7-day spray interval and a variable dose rate is being tested. In the UK, commercially available DSSs are used for c. 8% of the area. The validity of Smith Periods for the new population of P. infestans in the UK is currently being evaluated

    Sow body condition at weaning and reproduction performance in organic piglet production

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    The objective was to investigate the variation in backfat at weaning and its relations to reproduction results in organic sow herds in Denmark. The study included eight herds and 573 sows. The average backfat at weaning mean�13 mm; SD�4.2 mm) ranging from 10.5 to 17.3 mm among herds shows that it is possible to avoid poor body condition at weaning even with a lactation length of seven weeks or more. No main effect of backfat at weaning on reproduction performance was found, but the probability of a successful reproduction after weaning tended to decrease with decreasing backfat for first parity sows, whereas the opposite was the case for multiparous sows

    Changes in aerosol properties during spring-summer period in the Arctic troposphere

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    The change in aerosol properties during the transition from the more polluted spring to the clean summer in the Arctic troposphere was studied. A six-year data set of observations from Ny-Ålesund on Svalbard, covering the months April through June, serve as the basis for the characterisation of this time period. In addition four-day-back trajectories were used to describe air mass histories. The observed transition in aerosol properties from an accumulation-mode dominated distribution to an Aitken-mode dominated distribution is discussed with respect to long-range transport and influences from natural and anthropogenic sources of aerosols and pertinent trace gases. Our study shows that the air-mass transport is an important factor modulating the physical and chemical properties observed. However, the air-mass transport cannot alone explain the annually repeated systematic and rather rapid change in aerosol properties, occurring within a limited time window of approximately 10 days. With a simplified phenomenological model, which delivers the nucleation potential for new-particle formation, we suggest that the rapid shift in aerosol microphysical properties between the Arctic spring and summer is mainly driven by the incoming solar radiation in concert with transport of precursor gases and changes in condensational sink

    Evaluation of non-chemical seed treatment methods for the control of Alternaria dauci and A. radicina on carrot seeds

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    The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment) and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also not satisfactory with most of the formulated commercial micro-organism preparations. Based on the average of five field trials, one of these, BA 2552 (Pseudomonas chlororaphis), provided a low but significant increase in plant stand. Among the experimental micro-organisms, the best results were obtained with Pseudomonas sp. strain MF 416 and Clonostachys rosea strain IK726. A similar level of efficacy was provided by seed treatment with an emulsion (1%) of thyme oil in water. Good and consistent control was generally achieved with the physical methods aerated steam, hot water and electron treatment. Aerated steam treatment was, apart from the thiram-containing chemical standard, the best single treatment, and its performance may at least partially be due to extensive pre-testing, resulting in dosages optimally adapted to the respective seed lot. In some of the experiments the effect of the hot water treatment, which was tested at a fixed, not specifically adapted dosage, was significantly improved when combined with a Pseudomonas sp. MF 416 or C. rosea IK726 treatment. The results are discussed in relation to the outcome of experiments in which the same seed treatment methods and agents were tested in other seed-borne vegetable pathosystems

    Atmospheric constraints on the methane emissions from the East Siberian Shelf

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    Subsea permafrost and hydrates in the East Siberian Arctic Shelf (ESAS) constitute a substantial carbon pool, and a potentially large source of methane to the atmosphere. Previous studies based on interpolated oceanographic campaigns estimated atmospheric emissions from this area at 8&ndash;17 TgCH<sub>4</sub> yr<sup>−1</sup>. Here, we propose insights based on atmospheric observations to evaluate these estimates. The comparison of high-resolution simulations of atmospheric methane mole fractions to continuous methane observations during the whole year 2012 confirms the high variability and heterogeneity of the methane releases from ESAS. A reference scenario with ESAS emissions of 8 TgCH<sub>4</sub> yr<sup>−1</sup>, in the lower part of previously estimated emissions, is found to largely overestimate atmospheric observations in winter, likely related to overestimated methane leakage through sea ice. In contrast, in summer, simulations are more consistent with observations. Based on a comprehensive statistical analysis of the observations and of the simulations, annual methane emissions from ESAS are estimated to range from 0.0 to 4.5 TgCH<sub>4</sub> yr<sup>−1</sup>. Isotopic observations suggest a biogenic origin (either terrestrial or marine) of the methane in air masses originating from ESAS during late summer 2008 and 2009

    Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling

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    Methane stored in seabed reservoirs such as methane hydrates can reach the atmosphere in the form of bubbles or dissolved in water. Hydrates could destabilize with rising temperature further increasing greenhouse gas emissions in a warming climate. To assess the impact of oceanic emissions from the area west of Svalbard, where methane hydrates are abundant, we used measurements collected with a research aircraft (Facility for Airborne Atmospheric Measurements) and a ship (Helmer Hansen) during the Summer 2014 and for Zeppelin Observatory for the full year. We present a model-supported analysis of the atmospheric CH4_{4}mixing ratios measured by the different platforms. To address uncertainty about where CH4_{4} emissions actually occur, we explored three scenarios: areas with known seeps, a hydrate stability model, and an ocean depth criterion. We then used a budget analysis and a Lagrangian particle dispersion model to compare measurements taken upwind and downwind of the potential CH4_{4} emission areas. We found small differences between the CH4_{4} mixing ratios measured upwind and downwind of the potential emission areas during the campaign. By taking into account measurement and sampling uncertainties and by determining the sensitivity of the measured mixing ratios to potential oceanic emissions, we provide upper limits for the CH4_{4} fluxes. The CH4_{4} flux during the campaign was small, with an upper limit of 2.5 nmol m2^{-2} s1^{-1} in the stability model scenario. The Zeppelin Observatory data for 2014 suggest CH4_{4} fluxes from the Svalbard continental platform below 0.2 Tg yr1^{-1}. All estimates are in the lower range of values previously reported.MOCA—Methane Emissions from the Arctic OCean to the Atmosphere: Present and Future Climate Effects is funded by the Research Council of Norway, grant 225814. CAGE—Centre for Arctic Gas Hydrate, Environment and Climate research work was supported by the Research Council of Norway through its Centres of Excellence funding scheme grant 223259. eSTICC—eScience Tools for Investigating Climate Change in northern high latitudes is supported by Nordforsk as Nordic Center of Excellence grant 57001. NERC grants NE/I029293/1 (PI. H. Coe) and NE/I02916/1 (PI J. Pyle) and Methane & Other Greenhouse Gases in the Arctic—Measurements, Process Studies and Modelling (MAMM). The ERC through the ACCI project, project number 267760. The biogenic methane emission data from the LPX-Bern v1.2 model were provided by Renato Spahni. The methane emission data from the GAINS model were provided by IIASA. GFED data are available from http://www.globalfiredata.org/index.html. Airborne data were obtained using the BAe-146-301 Atmospheric Research Aircraft (ARA) flown by Directflight Ltd. and managed by the Facility for Airborne Atmospheric Measurements (FAAM), which is a joint entity of the Natural Environment Research Council (NERC) and the Met Office. Zeppelin and Helmer Hansen atmospheric measurement data are archived in EBAS (http://ebas.nilu.no/) for long-term preservation, access and use. All Zeppelin data for 2014: http://ebas.nilu.no/DataSets.aspx?stations=NO0042G&fromDate=2014-01-01&toDate=2014-12-31. All atmospheric data from RV Helmer Hanssen: http://ebas.nilu.no/DataSets.aspx?stations=NO1000R&fromDate=2014-01-01&toDate=2014-12-31 (password is required until the end of 2017)

    Negative Effect of Smoking on the Performance of the QuantiFERON TB Gold in Tube Test.

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    False negative and indeterminate Interferon Gamma Release Assay (IGRA) results are a well documented problem. Cigarette smoking is known to increase the risk of tuberculosis (TB) and to impair Interferon-gamma (IFN-γ) responses to antigenic challenge, but the impact of smoking on IGRA performance is not known. The aim of this study was to evaluate the effect of smoking on IGRA performance in TB patients in a low and high TB prevalence setting respectively. Patients with confirmed TB from Denmark (DK, n = 34; 20 smokers) and Tanzania (TZ, n = 172; 23 smokers) were tested with the QuantiFERON-TB Gold In tube (QFT). Median IFN-γ level in smokers and non smokers were compared and smoking was analysed as a risk factor for false negative and indeterminate QFT results. Smokers from both DK and TZ had lower IFN-γ antigen responses (median 0.9 vs. 4.2 IU/ml, p = 0.04 and 0.4 vs. 1.6, p < 0.01), less positive (50 vs. 86%, p = 0.03 and 48 vs. 75%, p < 0.01) and more false negative (45 vs. 0%, p < 0.01 and 26 vs. 11%, p = 0.04) QFT results. In Tanzanian patients, logistic regression analysis adjusted for sex, age, HIV and alcohol consumption showed an association of smoking with false negative (OR 17.1, CI: 3.0-99.1, p < 0.01) and indeterminate QFT results (OR 5.1, CI: 1.2-21.3, p = 0.02). Cigarette smoking was associated with false negative and indeterminate IGRA results in both a high and a low TB endemic setting independent of HIV status

    Effects of Companies’ Initiatives to Reduce Early Retirement Among Older Workers

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    Although active ageing policy and practice vary between countries, we believe that knowledge about the effects of Norwegian companies’ initiatives to delay early retirement is of interest for all countries striving to increase the employment rates of older workers. Since the agreement on a more inclusive working life (IW agreement) was signed in 2001, the Norwegian government and social partners have encouraged companies to develop a more senior-friendly policy and implement special measures to retain older workers. In this article, we evaluate the effects of such measures. Our research question is, have preventive measures offered by companies to employees aged 62 years and older contributed to reduced rates of early retirement? We use a ‘difference-in-differences’ approach and examine whether measures at the company level to counteract early retirement actually affect older employees’ retirement decisions, controlling for different individual and enterprise factors. This is done by comparing changes and differences in the individual likelihood of early retirement on the contractual pension (AFP scheme) and disability pension in the period 2002–2007 among employees 62 years of age in businesses with and without the corresponding preventive measures/instruments. The analyses show that the likelihood that a 62-year-old worker will retire on the AFP scheme has increased from 2002 to 2007. This applies equally to 62-year-old employees in enterprises that have enacted special measures to retain older workers as well as 62-year-olds in enterprises that have not enacted any such measures. On the other hand, the likelihood that a 62-year-old worker will retire because of disability decreased from 2002 to 2007, among employees in both the intervention enterprises and the control enterprises. However, when controlling for other relevant characteristics of individuals and enterprises, the analysis indicates that the measures as such have had no effect on the likelihood of 62-year-olds retiring

    Effects of Companies’ Initiatives to Reduce Early Retirement Among Older Workers

    Get PDF
    Although active ageing policy and practice vary between countries, we believe that knowledge about the effects of Norwegian companies’ initiatives to delay early retirement is of interest for all countries striving to increase the employment rates of older workers. Since the agreement on a more inclusive working life (IW agreement) was signed in 2001, the Norwegian government and social partners have encouraged companies to develop a more senior-friendly policy and implement special measures to retain older workers. In this article, we evaluate the effects of such measures. Our research question is, have preventive measures offered by companies to employees aged 62 years and older contributed to reduced rates of early retirement? We use a ‘difference-in-differences’ approach and examine whether measures at the company level to counteract early retirement actually affect older employees’ retirement decisions, controlling for different individual and enterprise factors. This is done by comparing changes and differences in the individual likelihood of early retirement on the contractual pension (AFP scheme) and disability pension in the period 2002–2007 among employees 62 years of age in businesses with and without the corresponding preventive measures/instruments. The analyses show that the likelihood that a 62-year-old worker will retire on the AFP scheme has increased from 2002 to 2007. This applies equally to 62-year-old employees in enterprises that have enacted special measures to retain older workers as well as 62-year-olds in enterprises that have not enacted any such measures. On the other hand, the likelihood that a 62-year-old worker will retire because of disability decreased from 2002 to 2007, among employees in both the intervention enterprises and the control enterprises. However, when controlling for other relevant characteristics of individuals and enterprises, the analysis indicates that the measures as such have had no effect on the likelihood of 62-year-olds retiring
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