17 research outputs found

    Vervolgonderzoek verhoogde nikkelgehalten in grondwater in de provincie Flevoland

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    Op meerdere plaatsen in Nederland en ook in Flevoland worden al langere tijd in het ondiepe grondwater nikkelgehalten aangetroffen die boven de streefwaarde (15 μg per l) en interventiewaarde (75 μg per l) liggen. Waarden tot boven de 400 μg per l komen voor. Vaak wordt gedacht aan een natuurlijke oorsprong. Een deskstudie die door het Louis Bolk Instituut is verricht gaf aanwijzingen dat bedrijfsactiviteiten toch ook een rol kunnen spelen. In voorliggend rapport worden drie hypotheses geformuleerd. Daarnaast doet dit rapport verslag van uitgevoerde experimenten die meer licht op deze hypotheses kunnen werpen. De hypotheses zijn: 1. Chelaten, EDTA en DTPA uit meststoffen of industriële activiteiten houden nikkel in oplossing. 2. Sulfaten uit meststoffen in combinatie met een afwisseling van zuurstofarme en zuurstofrijke omstandigheden stimuleren het in oplossing gaan of blijven van nikkel. 3. Nikkel zit onbedoeld vrij veel in meststoffen en wanneer die bij meststofbereidingsinstallaties in kassen worden gemorst kan nikkel in het grondwater terecht komen en verhoogde nikkelgehalten veroorzaken. Het onderzoek naar chelaten toont aan dat deze in zodanige gehalten aanwezig zijn dat deze potentieel tot verhoogde nikkelgehalten in het grondwater kunnen leiden. Een laboratoriumproef gaf duidelijke aanwijzingen dat sulfaat in combinatie met een afwisseling van zuurstofarme en zuurstofrijke omstandigheden tot hogere nikkelgehalten leidt. De in drie kassen gebruikte meststoffen bevatten nikkel en wanneer de meststoffen in geconcentreerde vorm in het grondwater komt veroorzaakt dit mogelijk voor een deel het probleem. De gehalten in deze meststoffen zijn overeenkomstig die in het grondwater van kassen met relatief hoge nikkelgehalten. Daarmee kunnen alle drie de hypotheses nog geldig zijn. Mogelijk is ook sprake van naast elkaar optredende processen. Er worden, gezien de omvang van het probleem, aanbevelingen gedaan om rond chelaten, sulfaat en meststoffen meer onderzoek te gaan doen: - bij EDTA: onderzoek naar het gehalte in meststoffen en naar de mate waarin chelaten als EDTA en DTPA van betekenis zijn; - bij sulfaat: meer fundamenteel onderzoek dichter bij de praktijksituatie; - bij meststoffen: meer onderzoek naar gehalten in meststoffen om de werkelijke bron te vinden

    Haemovigilance:current practices and future developments

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    Haemovigilance is the systematic surveillance of adverse events in the transfusion chain, and encompasses activities that contribute to the safety and quality in the process of blood donation and transfusion. From the start in the early 1990s, haemovigilance has put emphasis on different adverse reactions and incidents in recipients and subsequently in donors, pointing to vulnerabilities in the transfusion chain and areas for prevention. More recently, the monitoring of efficacy and efficiency of transfusion practice has been introduced in the concept of haemovigilance. The purpose of this review is to present an overview of the current status and future developments of haemovigilance. Haemovigilance is part of the quality systems of the blood collection establishments, transfusion laboratories and the transfusion institutions. The monitoring, investigation and analysis of adverse events generates relevant data for the quality cycle of these systems, driving continuous improvement in transfusion practice. Recommendations based on haemovigilance findings have led to changes in clinical guidelines and policies. Despite the progress haemovigilance has made, further developments are needed. Current challenges lie in the field of the establishment of haemovigilance systems in low resource settings, the international harmonisation of definitions and the prevention of underreporting. In addition, the causal relationship between the transfusion and the reaction is often unclear. Biomarkers may aid in the imputability assessment and their role in the diagnosis of transfusion reactions needs to be further investigated. Future developments are expected in automated reporting, the use of big data and increased shareability of international data, contributing to a better understanding of the causal mechanisms and risk factors, and to prevention of adverse events. Haemovigilance is an evolving discipline and will continue to contribute to improving the safety of blood donation and transfusion

    Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties

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    The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990-2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to analyze the spatial patterns and drivers of CO2 fluxes and test the accuracy and uncertainty of different statistical models. CO2 fluxes were upscaled at relatively high spatial resolution (1 km(2)) across the high-latitude region using five commonly used statistical models and their ensemble, that is, the median of all five models, using climatic, vegetation, and soil predictors. We found the performance of machine learning and ensemble predictions to outperform traditional regression methods. We also found the predictive performance of NEE-focused models to be low, relative to models predicting GPP and ER. Our data compilation and ensemble predictions showed that CO2 sink strength was larger in the boreal biome (observed and predicted average annual NEE -46 and -29 g C m(-2) yr(-1), respectively) compared to tundra (average annual NEE +10 and -2 g C m(-2) yr(-1)). This pattern was associated with large spatial variability, reflecting local heterogeneity in soil organic carbon stocks, climate, and vegetation productivity. The terrestrial ecosystem CO2 budget, estimated using the annual NEE ensemble prediction, suggests the high-latitude region was on average an annual CO2 sink during 1990-2015, although uncertainty remains high

    Global maps of soil temperature

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    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Global maps of soil temperature

    Get PDF
    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Global maps of soil temperature

    Get PDF
    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Global maps of soil temperature.

    Get PDF
    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Haemovigilance: current practices and future developments

    No full text
    Haemovigilance is the systematic surveillance of adverse events in the transfusion chain, and encompasses activities that contribute to the safety and quality in the process of blood donation and transfusion. From the start in the early 1990s, haemovigilance has put emphasis on different adverse reactions and incidents in recipients and subsequently in donors, pointing to vulnerabilities in the transfusion chain and areas for prevention. More recently, the monitoring of efficacy and efficiency of transfusion practice has been introduced in the concept of haemovigilance. The purpose of this review is to present an overview of the current status and future developments of haemovigilance. Haemovigilance is part of the quality systems of the blood collection establishments, transfusion laboratories and the transfusion institutions. The monitoring, investigation and analysis of adverse events generates relevant data for the quality cycle of these systems, driving continuous improvement in transfusion practice. Recommendations based on haemovigilance findings have led to changes in clinical guidelines and policies. Despite the progress haemovigilance has made, further developments are needed. Current challenges lie in the field of the establishment of haemovigilance systems in low resource settings, the international harmonisation of definitions and the prevention of underreporting. In addition, the causal relationship between the transfusion and the reaction is often unclear. Biomarkers may aid in the imputability assessment and their role in the diagnosis of transfusion reactions needs to be further investigated. Future developments are expected in automated reporting, the use of big data and increased shareability of international data, contributing to a better understanding of the causal mechanisms and risk factors, and to prevention of adverse events. Haemovigilance is an evolving discipline and will continue to contribute to improving the safety of blood donation and transfusion

    Contaminants and micro-organisms in Dutch organic food products; comparison with conventional products

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    Organic products were analysed for the presence of contaminants, micro-organisms and antibiotic resistance and compared with those from conventional products. No differences were observed in the Fusarium toxins deoxynivalenol and zearalenone in organic and conventional wheat, both during a dry period and a very wet period promoting the production of these toxins. Nitrate levels in head lettuce produced organically in the open field were much lower than those in conventional products. In iceberg lettuce and head lettuce from the green house no differences were detected. Organically produced carrots contained higher nitrate levels than conventional products. Both organic and conventional products contained no residues of non-polar pesticides above the legal limits, although some were detected in conventional lettuce. Organic products contained no elevated levels of heavy metals. Salmonella was detected in 30% of pig faeces samples obtained from 30 organic farms, similar to the incidence at conventional farms. At farms that switched to organic production more then 6 years ago, no Salmonella was detected, with the exception of one stable with young pigs recently purchased from another farm. No Salmonella was detected in faeces at the nine farms with organic broilers, and at one out of 10 farms with laying hens. This is comparable to conventional farms where the incidence for Salmonella lies around 10%. Campylobacter was detected in faeces at all organic broiler farms, being much higher than at conventional farms. One of the most remarkable results was the fact that faeces from organic pigs and broilers showed a much lower incidence of antibiotic resistant bacteria, except for Campylobacter in broilers. It is concluded that the organic products investigated scored equally good as conventional products with regard to food safety and at the same time show some promising features with respect to antibiotic resistance
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