27 research outputs found

    Het percentage regionaal eiwit in het Nederlandse mengvoer : actualisatie voor 2018

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    Wageningen University & Research onderzocht de herkomst van eiwitrijke diervoedergrondstoffen (>154 g/kg ruw eiwit) in het Nederlandse mengvoer voor de jaren 2011, 2013, 2014, 2015 en 2018. Daarbij werd 'regionaal geproduceerde eiwit' gedefinieerd als eiwit in diervoeder, geleverd door eiwitrijke grondstoffen die afkomstig zijn van in Europa geteelde gewassen. Gegevens over de gebruikte hoeveelheden grondstoffen, eiwitgehaltes van deze producten en hun oorsprong (regionaal versus niet-regionaal) zijn gecombineerd om het aandeel regionaal geproduceerde eiwitten in de vijf grootste Nederlandse veehouderijsectoren (melkvee, vleesvee, varkenshouderij, leghennen en vleespluimvee) te verkrijgen, alsmede voor de veehouderij als geheel. De regionaal geproduceerde volumes eiwitrijke diervoedergrondstoffen werden berekend als eiwitvolume en totaal volume. In deze studie ligt de focus op eiwit afkomstig uit mengvoergrondstoffen en is eiwit afkomstig uit ruwvoer en enkelvoudige grondstoffen buiten beschouwing gelaten. Wel is een variant doorgerekend waarin ook de hoeveelheid eiwit uit eiwitrijke vochtrijke diervoeders is meegenomen. Op basis van eiwitvolume was het aandeel eiwit afkomstig van eiwitrijke diervoedergrondstoffen van regionale oorsprong in mengvoeders voor alle diercategorieën samen 39% in 2011, 41% in 2013, 48% in 2014, 38% in 2015 en 47% in 2018. Wanneer ook eiwitrijke vochtrijke bijproducten worden meegenomen, was het aandeel eiwit van regionale oorsprong in 2018 50%. Als we kijken naar de herkomst van het eiwit uit alle mengvoergrondstoffen, waarbij we dus ook de grondstoffen meenemen met minder dan 154 g/kg ruw eiwit zoals de granen, dan blijkt over de periode 2011 - 2018 dat 56 tot 65% van het eiwit in mengvoer van regionale herkomst is

    A global database for metacommunity ecology, integrating species, traits, environment and space

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    The use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. To address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; “CESTES”. Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. The CESTES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CESTES database provides an important opportunity for synthetic trait-based research in community ecology

    Feiten en cijfers vergroening GLB 2021

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    Voorliggend rapport presenteert de uitkomsten van een monitoring van de vergroening voor het jaar 2021volgens de geactualiseerde methode en gebruikmakend van gegevens die werden verzameld insamenwerking met RVO. De evaluatie laat zien hoe en door welke boeren maatregelen voor blijvendgrasland, gewasdiversificatie en ecologische aandachtsgebieden en tevens de equivalente maatregelen zijngekozen. De resultaten werden geïnterpreteerd wat betreft te verwachten effecten in relatie tot de gesteldedoelen van de vergroening. In de analyse worden ook de resultaten uit de voorgaandemonitoringsrapportage betrokken, zodat een beeld ontstaat van de vergroening na zeven jaar

    Biodiversity conservation on farmland: start at the landscape level

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    For decades, policy makers, NGO’s, companies in the agro-production chain and farmers are struggling to improve biodiversity in Europe’s countryside. Most efforts focus on individual farms. However, we know that in biodiversity conservation the landscape level is highly relevant. Basic conditions like the area of non-cultivated land are of major importance for most species groups. Just like the close proximity of nature areas. The EU proposed in its Common Agricultural Policy that 3–7% of EU farmland should be managed as Ecological Focus Area in order to halt biodiversity loss. We empirically assessed the implications of this policy by evaluating the effects of the density of natural elements in the agricultural landscapes of The Netherlands on multi-taxon species richness, including vascular plants, breeding birds, butterflies, hoverflies, dragonflies, and grasshoppers. We found that species richness increased as a function of the proportion of natural elements in the landscape. Even landscapes with 3–7% of natural elements harboured generally 37–75% of maximum species richness. However, differences between the 3 and 7% limits were considerable for butterflies, birds, and hoverflies. To improve biodiversity it is necessary to develop tailor-made approaches at regional levels, including all relevant stakeholders.peerReviewe

    Improved testing of species traits–environment relationships in the fourth-corner problem

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    The fourth corner problem entails estimation and statistical testing of the relationship between species traits and environmental variables from the analysis of three data tables. Dray and Legendre (2008, Ecology, 89, 3400-34) proposed and evaluated five permutation methods for statistical significance testing, including a new two-step testing procedure. However, none of these attained the correct type I error in all cases of interest. We solve this problem by showing that a small modification of their two-step procedure controls the type I error in all cases. The modification consists of adjusting the significance level from va to a or, equivalently, of reporting the maximum of the individual P-values as the final one. The test is also applicable to the three table ordination method RL

    Participatory Modeling With QUICKScan to Shape Sustainable Urban Development

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    Current spatial planning methods are often technocratic, slow, fail to use the right kind of evidence or do not involve (all) the actors needed to create support and consensus. We present a method that facilitates the use of evidence (data) in participatory spatial planning processes, resulting in a joint understanding of the most important causalities, as a means to build capacity across actors. QUICKScan is a participatory modeling method that links stakeholder- and decision maker knowledge and preferences to available spatial and spatio-statistical data, and is designed for group use in a multi-stakeholder workshop setting. We describe four urban QUICKScan applications, that vary in objective, scale and institutional setting. The most critical in organizing a QUICKScan session is to: (i) include crucial participants in a single plenary workshop (decision maker, local data expert, and local thematic experts), (ii) create an open atmosphere in which each and everyone's opinion is treated equally, (iii) dialogue is more important than an abundance of detailed spatial data, and (iv) start with simple modeling rules and iterate often while expanding the set of rules and trying out alternatives

    Bonaire 2050 : Putting the vision into numbers

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    Bonaire is facing major challenges including (mass) tourism, population growth, urban expansion, climate change, biodiversity loss and the unilateral dependency on tourism. In thirty years, Bonaire will inevitably look different. Here, two different possible futures are presented, to form a basis for dialogue amongst stakeholders and to stimulate a positive change and sustainability on Bonaire. One of these scenarios follows current trends (business-as-usual), and the other bends those trends into a nature-inclusive future after a vision developed by a trans-disciplinary team of researchers, local experts and stakeholders. For both scenarios drivers and impacts are visualized and documented on climate, tourist numbers, population,infrastructure, resources, land use, erosion and nature. Visualizing scenarios is one important piece in creating awareness about the future as it allows to shed light of the difficult to grasp long-term effects, and explicitly showcases current trends. It gives opportunities to imagine a future that looks different from the prognosis, and to inspire to work towards a sustainable and desirable future
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