160 research outputs found

    Nitrogen deposition and grass encroachment in calcareous and acidic Grey dunes (H2130) in NW-Europe

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    We present an overview of high nitrogen deposition effects on coastal dune grasslands in NW-Europe (H2130), especially concerning grass encroachment in calcareous and acidic Grey Dunes. The problem is larger than previously assumed, because critical loads are still too high, and extra N-input from the sea may amount to 10 kg ha−1 yr−1. Grass encroachment clearly leads to loss of characteristic plant species, from approximately 16 in open dune grassland to 2 in tall-grass vegetation. Dune zones differ in grass encroachment, due to the chemical status of the soil. In calcareous and iron-rich dunes (Renodunal district), grass encroachment showed a clear gradient over the dune area. Grass encroachment is low in calcareous foredunes, due to low P-availability, and large grazers were not needed to counteract grass encroachment after 2001. In partly decalcified middle dunes, P-availability and grass encroachment are high due to dissolution of calcium phosphates, and grazing only partially helped to control this. In acidic, iron-rich hinterdunes, grass encroachment gradually increased between 1990 and 2014, possibly because P-availability increased with time due to increased soil organic matter content. In acidic, iron-poor dunes (Wadden district), grass encroachment is a large problem, because chemical P-fixation with Ca or Fe does not occur. Large grazers may however reduce tall-grass cover. High cumulative N-deposition could theoretically lead to increased N-storage and N-mineralization in the soil. Mineralization indeed increased with N-deposition, but in 15N experiments, most ammonium was converted to nitrate, and storage in soil organic matter was low. Soil N-storage is probably reduced by high nitrate leaching, which will favour dune restoration when N-deposition levels decrease

    Annual survey air quality 2001

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    The air quality for 2001 is found to strongly resemble that for 2000. The decreasing trend in concentrations seen in the nineties, is still valid on the whole. Concerning the meteorological influences, 2001 can be considered as a normal year. Widespread exceedances occurred for ozone and PM10, and in the deposition of potential acid and total nitrogen. In the urban environment, exceedances of the annual mean limit value for NO2 occurred along road length of about 2000 km. Calculations for benzene and benzo[a]pyrene showed that exceedances were incidental. This annual air quality survey provides an overview of the air quality and the load placed on soils and surface water by atmospheric deposition in the Netherlands, on the basis of measurements and model calculations. The report describes global, photochemical, acidifying, particulate and local air pollution. Special attention has been paid to the Dutch air quality in relation to the new European legislation on air quality.Als we de luchtkwaliteit over 2001 vergelijken met die van 2000 blijken deze in grote lijnen met elkaar overeen te komen. De trendmatige daling van concentraties heeft zich in grote lijnen doorgezet. 2001 was wat meteorologische invloed betreft een normaal jaar. Normoverschrijdingen op landelijke schaal hebben zich voorgedaan van ozon, zwevende deeltjes (PM10), depositie van potentieel zuur en stikstof. In de stedelijke omgeving is de jaargemiddelde norm NO2 overschreden langs een weglengte van circa 2000 km. Voor benzeen en benzo[a]pyreen geven berekeningen aan dat incidenteel overschrijdingen van grenswaarden kunnen zijn voorgekomen. In het jaaroverzicht luchtkwaliteit 2001 wordt op basis van metingen en modelberekeningen een samenvattend beeld gegeven van de luchtkwaliteit en de belasting van bodem en oppervlaktewater door atmosferische depositie in Nederland over 2001. Het rapport beschrijft de onderwerpen: mondiale, fotochemische, verzurende, deeltjesvormige en lokale luchtverontreiniging. Als extra onderwerp is een hoofdstuk opgenomen over de Nederlandse luchtkwaliteit in relatie tot de nieuwe Europese wetgeving voor luchtkwaliteit

    Grootschalige concentratie- en depositiekaarten Nederland : Rapportage 2014

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    Nieuwe concentratie- en depositiekaarten voor NSL en PAS Het RIVM heeft kaarten opgesteld waarop staat aangegeven wat in 2013 in Nederland de concentraties in de lucht waren van onder andere stikstofdioxide en fijn stof. Ook is op een kaart aangegeven in welke mate stikstof op de bodem neerslaat. Daarnaast zijn toekomstberekeningen voor deze stoffen gemaakt voor de periode 2015- 2030. De kaarten worden gebruikt voor de monitoring van het Nationaal Samenwerkingsprogramma Luchtkwaliteit (NSL) en de Programmatische Aanpak Stikstof (PAS). Hiermee worden onder andere de effecten van ruimtelijke plannen getoetst Stikstofdioxideconcentraties voor 2015 veelal lager De gemeten concentraties stikstofdioxide waren in 2013 lager dan in 2012. De concentraties die voor 2015 zijn berekend, zijn op de meeste locaties lager dan vorig jaar was geraamd. Toch blijven er een aantal probleemgebieden bestaan waarin de verwachte concentraties hoger zijn dan vorig jaar geraamd, vooral in de regio's Rotterdam en Den Haag. Wat de verwachte overschrijdingen van de normen in 2015 betreft, zal dat in Amsterdam en Utrecht op minder locaties aan de orde zijn dan eerder was ingeschat, en in Rotterdam op meer locaties Drie oorzaken voor deze aangepaste verwachting zijn het belangrijkst. Als eerste is bij de ramingen een correctie aangebracht voor systematische verschillen tussen gemeten en berekende stikstofdioxideconcentraties. Ten tweede stoten de nieuwste modellen vrachtauto's minder stikstofoxiden uit dan eerder was ingeschat. Ten derde zijn effecten meegenomen van het SER-energieakkoord uit 2013. Hierin zijn afspraken gemaakt om energie te besparen bij huishoudens, industrie en landbouw en het aandeel alternatieve energiebronnen als wind- en zonne-energie te vergroten Roetconcentraties dalen naar verwachting verder Steeds meer dieselauto's hebben een filter, waarmee roet effectief wordt afgevangen. Op basis van het huidige beleid wordt geschat dat de roetconcentratie de komende jaren verder daalt, en in 2020 bijna zal zijn gehalveerd ten opzicht van het huidige niveau Daling stikstofdepositie onveranderd De neerslag van stikstof op de bodem in Nederland daalt naar verwachting de komende jaren in ongeveer dezelfde mate als vorig jaar was geraamd. Een dalende stikstofdepositie is een voorwaarde voor natuurbehoudNew maps of concentrations and depositions for NSL and PAS In this report, the National Institute for Public Health and the Environment (RIVM) presents the latest maps of air concentrations in the Netherlands for several substances, including nitrogen dioxide and particulate matter for 2013. It also presents the maps for the deposition of nitrogen compounds to the soil for that year. Calculations for the future (2015-2030) have also been made. The maps are being used in the national air quality collaboration programme (NSL) and for the programmatic approach to nitrogen (PAS) for monitoring new spatial planning projects Nitrogen dioxide concentrations mostly lower for 2015 The measured concentrations of nitrogen dioxide were in 2013 lower than in 2012. Concentrations calculated for 2015 are at most locations below last year's estimates. Yet, there remain a number of areas where the expected concentrations are higher than last year's estimates, especially in the vicinity of Rotterdam and The Hague. The limit value for the nitrogen dioxide concentration will probably be exceeded in fewer locations in Amsterdam and Utrecht than was estimated earlier and in more locations in Rotterdam in 2015 There are three main reasons for these adjusted expectations of future concentrations. First, a correction is applied to projections of nitrogen dioxide concentrations for systematic differences between measured and calculated concentrations. Second, the latest truck models emit less nitrogen oxides than was previously expected. Third, the effects of the SER energy agreement from 2013 have been taken into account. Arrangements have been made in the agreement to save energy in households, industry and agriculture, and to increase the share of alternative energy sources, such as, wind and solar energy Soot concentrations are expected to decrease further More and more diesel cars have a filter, which is effective in capturing soot. It is expected that, based on the current policies, the soot concentrations will continue to decrease in the coming years and will be reduced by almost 50 percent by 2020 compared to current levels Decrease in nitrogen deposition unchanged The deposition of nitrogen to the soil in the Netherlands is expected to decrease in the coming years by approximately the same amount as was estimated last year. A reduction in nitrogen deposition is a prerequisite for nature conservationMinisterie van I&

    Begrazingsintensiteit en insectenrijkdom in heideterreinen

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    Begrazing als beheervorm wordt breed toegepast in heidegebieden om op een betaalbare manier openheid van het landschap en variatie in levensgemeenschappen te handhaven. De wijze van uitvoering luistert daarbij nauw, maar goede inzichten in de effecten van graasdruk op insecten ontbraken tot nu toe. Dit artikel geeft de resultaten van een veldonderzoek naar de invloed van begrazingsintensiteit op de soortenrijkdom van sprinkhanen, Heidecicade, vlinders, zweefvliegen, bijen en mieren in Noord-Brabantse heideterreinen

    Enhancing national environmental monitoring through local citizen science

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    Citizen science, the active participation of the public in scientific research projects, is a rapidly expanding field in open science and open innovation. It provides an integrated model of public knowledge production and engagement with science. As a growing worldwide phenomenon, it is invigorated by evolving new technologies that connect people easily and effectively with the scientific community. Catalysed by citizens’ wishes to be actively involved in scientific processes, as a result of recent societal trends, it also offers contributions to the rise in tertiary education. In addition, citizen science provides a valuable tool for citizens to play a more active role in sustainable development. This book identifies and explains the role of citizen science within innovation in science and society, and as a vibrant and productive science-policy interface. The scope of this volume is global, geared towards identifying solutions and lessons to be applied across science, practice and policy. The chapters consider the role of citizen science in the context of the wider agenda of open science and open innovation, and discuss progress towards responsible research and innovation, two of the most critical aspects of science today

    Simultaneous in-field boost for patients with 1 to 4 brain metastasis/es treated with volumetric modulated arc therapy: a prospective study on quality-of-life

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    <p>Abstract</p> <p>Purpose</p> <p>To assess treatment toxicity and patients' survival/quality of life (QoL) after volumetric modulated arc therapy (VMAT) with simultaneous in-field boost (SIB) for cancer patients with 1 - 4 brain metastases (BM) treated with or without surgery.</p> <p>Methods and Materials</p> <p>Between March and December 2010, 29 BM patients (total volume BM, < 40 cm<sup>3</sup>) aged < 80 years, KPS ≥ 70, RPA < III were included in this prospective trial. Whole brain VMAT (30 Gy) and a SIB to the BM (40 Gy) was delivered in 10 fraction. Mean age was 62.1 ± 8.5 years. Fifteen (51.7%) underwent surgery. KPS and MMSE were prospectively assessed. A self-assessed questionnaire was used to assess the QoL (EORTC QLQ-C30 with -BN20 module).</p> <p>Results</p> <p>As of April 2011 and after a mean FU of 5.4 ± 2.8 months, 14 (48.3%) patients died. The 6-month overall survival was 55.1%. Alopecia was only observed in 9 (31%) patients. In 3-month survivors, KPS was significantly (<it>p </it>= 0.01) decreased. MMSE score remained however stable (<it>p </it>= 0.33). Overall, QoL did decrease after VMAT. The mean QLQ-C30 global health status (<it>p </it>= 0.72) and emotional functional (<it>p </it>= 0.91) scores were decreased (low QoL). Physical (<it>p </it>= 0.05) and role functioning score (<it>p </it>= 0.01) were significantly worse and rapidly decreased during treatment. The majority of BN20 domains and single items worsened 3 months after VMAT except headaches (<it>p </it>= 0.046) and bladder control (<it>p </it>= 0.26) which improved.</p> <p>Conclusions</p> <p>The delivery of 40 Gy in 10 fractions to 1 - 4 BM using VMAT was achieved with no significant toxicity. QoL, performance status, but not MMSE, was however compromised 3 months after treatment in this selected cohort of BM patients.</p

    Individual quality of life: adaptive conjoint analysis as an alternative for direct weighting?

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    In the schedule for the evaluation of individual quality of life (SEIQoL) the weights for five individualized quality of life domains have been derived by judgment analysis and direct weighting (DW). We studied the feasibility and validity of adaptive conjoint analysis (ACA) as an alternative method to derive weights in 27 cancer patients and 20 patients with rheumatoid arthritis. Further, we assessed the convergence between direct weights and weights derived by ACA, and their correlation with global quality-of-life scores. All respondents finished the ACA task, but one in five respondents were upset about the ACA task. Further, the task was vulnerable to judgment ‘errors’, such as inconsistent answers. The agreement between the two weights was low. Both weighted index scores were strongly correlated to the unweighted index score. The relationships between the index score and scores on a visual analogue scale for global individual quality of life and global quality of life were similar whether or not the index score was calculated with DW weights, with ACA weights, or without using weights. We conclude that, because weights did not improve the correlation between the index score and global quality of life scores, it seems sufficient to use the unweighted index score as a measure for global individual quality of life
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