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The province of Flevoland in the Netherlands has several ‘natural’ areas, but none of them have a habitat type that is sensitive for nitrogen deposition connected. The question is if this correct, are there no nitrogen deposition sensitive vegetation types in Flevoland? A first inventory shows that the province of Flevoland does have soil types and vegetation types that are vulnerable for nitrogen deposition. Indicators of an effect of nitrogen deposition are in increase of black Berry and Sting nettle and a decrease of soil pH and calcium content of the soil. A first inventory also shows that for a major part of the surface of natural areas the nitrogen deposition exceeds the threshold value for a good vitality of the vegetation., De provincie Flevoland heeft verschillende natuurgebieden, maar aan geen van de gebieden is een habitattype gekoppeld dat op een gevoeligheid voor stikstofdepositie duidt. De vraag is of dit terecht is. Een eerste inventarisatie laat zien dat er in Flevoland wel degelijk bodemtypen en vegetatietypen voorkomen in natuurgebieden die gevoelig zijn voor stikstofdepositie. Processen die duiden op effecten van stikstofdepositie zijn o.a. verbraming, toename van brandnetels en een indicatie van een verlaging van de bodem-pH en het calciumgehalte in de bodem. Een eerste inventarisatie laat ook zien dat voor een groot deel van het oppervlak van de natuur de stikstofdepositie hoger is dan goed is voor een goede ontwikkeling van de natuur.

Door de vereniging Ons EerbeekBrummen zijn vier vragen neergelegd bij de Wetenschapswinkel van de WUR aangaande de kap van een bos ten behoeve van de bouw van een distributiecentrum bij Eerbeek en het instellen van een compensatiebos. De vier vragen zijn: 1. Hoeveel stikstof neemt dit bos nu per ha per jaar op? 2. Hoeveel stikstof wordt nu van het dak afgespoeld en met het regenwater geïnfiltreerd in de bodem en wat gebeurt er dan mee? 3. Wanneer, na hoeveel jaar, is een compensatiebos op hetzelfde stikstof opnemend niveau en hoeveel is de niet opgenomen stikstof in die 50 of 100 jaar? 4. Kun je het niet opgenomen deel van de stikstof als extra uitstoot meewegen in de vergunningsaanvraag. Op basis van gemiddelde groei en stikstofvastlegging zijn de vragen over de stikstofvastlegging beantwoord. De afspoeling van stikstof van het dak is berekend op basis van de voorlopige plannen over het distributiecentrum op basis van het dakoppervlak. Het huidige bos (vooral grove den) neemt nu ongeveer 1,6 kg/ha/jr op. Bij een nu gepland vloeroppervlak van 32.000 m2 bedraagt de afspoeling 63,9 kg/jr. Het is onbekend of dit water naar het riool zal gaan of geïnfiltreerd zal worden. Het compensatiebos zal naar verwachting binnen 10 jaar op hetzelfde stikstofvastleggingsniveau zitten als het huidige bos. Na ongeveer 25 jaar zal er ongeveer even veel stikstof zijn vastgelegd door het compensatiebos als het huidige bos; het nieuwe bos haalt de aanvankelijke achterstand in. Er zou voor gekozen kunnen worden om het compensatiebos nu alvast aan te planten en zo de vastlegging nu al te beginnen zodat er geen tijdelijke verminderde vastlegging ontstaat. De waarden zijn gebaseerd op gemiddelden voor groei en stikstofvastlegging en bevatten daarom enige onzekerheid. In de vergunningverlening zou er aandacht moeten zijn voor de stikstof die afspoelt van de daken. Als dit direct in de bodem infiltreert, kan dit tot problemen leiden met het grondwater. Om dit te voorkomen zou het water eerst

This report describes the technical background to the indicators used to measure progress towards the ‘Environmental conditions for nature’ targets as described on the website of the Assessment of the Dutch Human Environment 2020. The selected indicators should provide answers to the following questions: What progress is being made with improving the environmental conditions in nature conservation areas? and Is the creation of the national ecological network leading to larger and better connected areas of natural habitat? The policy-relevant indicators selected for the Assessment of the Dutch Human Environment report are: 1. Ecosystem quality and trends in groundwater-dependent ecosystems 2. Ecosystem quality and trends in soil pH 3. Ecosystem quality and trends in nitrogen availability 4. Spatial connectivity of the national ecological network. The indicators focus on terrestrial nature., Dit rapport beschrijft de technische achtergronden van de indicatoren die het doelbereik van ‘Milieucondities natuur’ – zoals beschreven in de Digitale Balans 2020 – onderbouwen. De in dit rapport beschreven indicatoren moeten een antwoord geven op de vragen: “Wat zijn de verbeteringen in milieucondities van natuurgebieden? En is de ruimtelijke samenhang van natuurgebieden met realisatie van het NNN verbeterd?” De voor de Balans van de Leefomgeving geselecteerde beleidsrelevante indicatoren zijn daarom: 1. Geschiktheid grondwaterstand verdrogingsgevoelige landnatuur 2. Geschiktheid zuurgraad bodem verzuringsgevoelige landnatuur 3. Geschiktheid stikstofdepositie stikstofgevoelige landnatuur 4. Geschiktheid ruimtelijke condities landnatuur De indicatoren zijn gericht op landnatuur.

The database underlying the Model for Nature Policy (MNP) is the Management Types Map. Several of the management types are defined in broad terms, which leads to undesirable outcomes in the modelling. To solve this problem a number of types have been downscaled. This process of downscaling was performed on the large-scale terrestrial management types and the Marsh and Open Dune management types. Several data sources were used for the downscaling, including the Land Use Database of the Netherlands (LGN). This report records the downscaling method developed in 2015 for the ex ante analysis of the Nature Pact, which was the starting point for newer versions of the Management Types Map. The map described here has already been replaced by a newer version and an improved downscaling method., De beheertypenkaart wordt door de MNP gebruikt als basisbestand. Een aantal beheertypen zijn breed gedefinieerd, wat tot ongewenste effecten leidt bij de modelering. Om dit op te lossen zijn een aantal typen opgedeeld. Dit proces van neerschaling is uitgevoerd voor de terrestrische grootschalige beheertypen en de beheertypen Moeras en Open duin. Voor de neerschaling zijn meerdere bronnen gebruikt, zoals LGN en de bodemtypenkaart. Dit rapport borgt de methode van de neerschaling, zoals die in 2015 ontwikkeld is voor de ex-anteanalyse Natuurpact en die als startpunt heeft gediend voor nieuwere versies van de beheertypenkaart. De hier beschreven kaart is inmiddels vervangen door een nieuwere versie en een verbeterde neerschalingsmethode.

Nitrogen deposition is influencing the quality of Habitat types. To assess at what deposition level the quality is influenced significantly critical loads have been estimated. To estimate the extent of the quality loss we estimated doses-response curves for nitrogen deposition per habitat type. This was done by collecting field data from empirical gradient studies and by estimating response curves for habitat types based on response curves of qualifying species per habitat type. The latter also includes a study to the response of so-called displacement species. The number of empirical studies is very limited but the results from the view that are available are very promising. Statistical relations could be estimated for 60 out of 61 nitrogen deposition sensitive habitat types occurring in the Netherlands. Comparison between the empirical and statistical relations showed that they showed very similar responses for part of the habitat types and no relation for a minor part of the types.

Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no

Plant species occurrence in Europe is affected by changes in nitrogen deposition and climate. Insight into potential future effects of those changes can be derived by a model approach based on field-based empirical evidence on a continental scale. In this paper, we present a newly developed empirical model PROPS, predicting the occurrence probabilities of plant species in response to a combination of climatic factors, nitrogen deposition and soil properties. Parameters included were temperature, precipitation, nitrogen deposition, soil pH and soil C/N ratio. The PROPS model was fitted to plant species occurrence data of about 800,000 European relevés with estimated values for pH and soil C/N ratio and interpolated climate and modelled N deposition data obtained from the Ensemble meteo data set and EMEP model results, respectively. The model was validated on an independent data set. The test of ten species against field data gave an average Pearson's r-value of 0.79. PROPS was applied to a grassland and a heathland site to evaluate the effect of scenarios for nitrogen deposition and climate change on the Habitat Suitability Index (HSI), being the average of the relative probabilities, compared to the maximum probability, of all target species in a habitat. Results for the period 1930–2050 showed that an initial increase and later decrease in nitrogen deposition led to a pronounced decrease in HSI, and with dropping nitrogen deposition to an increase of the HSI. The effect of climate change appeared to be limited, resulting in a slight increase in HSI.

Forest understory plant communities in the eastern United States are often diverse and are potentially sensitive to changes in climate and atmospheric inputs of nitrogen caused by air pollution. In recent years, empirical and processed-based mathematical models have been developed to investigate such changes in plant communities. In the study reported here, a robust set of understory vegetation response functions (expressed as version 2 of the Probability of Occurrence of Plant Species model for the United States [US-PROPS v2]) was developed based on observations of forest understory and grassland plant species presence/absence and associated abiotic characteristics derived from spatial datasets. Improvements to the US-PROPS model, relative to version 1, were mostly focused on inclusion of additional input data, development of custom species-level input datasets, and implementation of methods to address uncertainty. We investigated the application of US-PROPS v2 to evaluate the potential impacts of atmospheric nitrogen (N) and sulfur (S) deposition, and climate change on forest ecosystems at three forested sites located in New Hampshire, Virginia, and Tennessee in the eastern United States. Species-level N and S critical loads (CLs) were determined under ambient deposition at all three modeled sites. The lowest species-level CLs of N deposition at each site were between 2 and 11 kg N/ha/yr. Similarly, the lowest CLs of S deposition, based on the predicted soil pH response, were less than 2 kg S/ha/yr among the three sites. Critical load exceedance was found at all three model sites. The New Hampshire site included the largest percentage of species in exceedance. Simulated warming air temperature typically resulted in lower maximum occurrence probability, which contributed to lower CLs of N and S deposition. The US-PROPS v2 model, together with the PROPS-CLF model to derive CL functions, can be used to develop site-specific CLs for understory plants within broad regi

Question: To assess the acidification process, nationwide information about soil pH on a site level is called for. Measurements of soil pH may be used, however there are not sufficient measurements available to map soil pH nationwide on site level. Instead we developed a soil pH map based on vegetation data. Location: Natural terrestrial areas in The Netherlands. Methods: 271,693 vegetation plots were used to estimate average soil pH per plot with indicator values, based on field measurements, of plant species. By spatial interpolation average pH values between the plots, with the soil type, groundwater table and vegetation management type as ancillary explanatory variables we created a soil pH map. The map covers all terrestrial nature areas (all areas that are not built up areas, agricultural areas and infrastructural areas) in the Netherlands with a map resolution of 25 × 25 m2 raster cells. Results: The predicted pH of the map varied between 3.0 and 8.6 with standard errors between 0.13 and 0.93. Most of the standard errors range from 0.4 to 0.55, with an average just below 0.5 pH unit. Cross-validation shows that for 33% the difference between observed and predicted is between −0.1 and 0.1 pH-unit and for 83% the difference is between −0.5 and 0.5 pH-unit. Validation shows that the pH map is unbiased (mean error is almost zero), accurate (root mean squared error is 0.64) and nicely captures spatial patterns (r = 0.77). We applied the pH map to assess the impact of acidification on the abiotic quality of nature areas in the Netherlands. Conclusions: The model fit in the predicted soil pH is in good resulting in a low standard error and a high correlation. The measures taken to prevent acidic deposition causing further acidifying of nature areas can be considered as successful.

If humans are going to establish a base on the Moon or on Mars they will have to grow their own crops. An option is to use Lunar and Martian regolith. These regoliths are not available for plant growth experiments, therefore NASA has developed regolith simulants. The major goal of this project was to cultivate and harvest crops on these Mars and Moon simulants. The simulants were mixed with organic matter to mimic the addition of residues from earlier harvests. Ten different crops, garden cress, rocket, tomato, radish, rye, quinoa, spinach, chives, pea and leek were sown in random lines in trays. Nine of the ten species grew well with the exception of spinach. It was possible to harvest edible parts for nine out of ten crops. The total biomass production per tray was highest for the Earth control and Mars soil simulant and differed significantly from Moon soil simulant. The seeds produced by three species were tested for germination (radish, rye and cress). The germination on Moon soil simulant was significantly lower in radish than for the Earth control soil.

Wageningen Environmental Research and PBL Netherlands Environmental Assessment Agency have developed MNP version 4.0 (Model for Nature Policy; MetaNatuurplanner) to determine the impacts of policy and management activities on biodiversity at the national and regional scale. The model predicts the persistence of species protected under nature policy by assessing the availability of sufficiently large connected areas of good habitat quality in the landscape . It does not assess the actual presence of these species. The model uses correlations between environmental, water and land use parameters and the sustainable conservation of biodiversity, and is used for identifying conflicts, policy evaluation and national and regional scenario studies. Results are aggregated to form indicators for Dutch and European policy. This report describes all the aspects of the model that are needed to obtain the Statutory Research Tasks Unit for Nature & the Environment quality status A for models. MNP will be further developed and validated in the coming years, Wageningen Environmental Research en het Planbureau voor de Leefomgeving hebben de MetaNatuurplanner versie 4.0 (Model for Nature Policy, MNP) ontwikkeld om op nationale of regionale schaal de effecten van beleid en beheeringrepen op de biodiversiteit te bepalen. Het model beoordeelt of er voldoende grote aaneengesloten gebieden met een goede kwaliteit in het landschap aanwezig zijn, zodat soorten die in het natuurbeleid worden beschermd potentieel duurzaam voor kunnen komen. Er wordt niet beoordeeld of soorten daadwerkelijk voorkomen. Het model legt daarbij relaties tussen de milieu-, water- en ruimtecondities en de duurzame instandhouding van de biodiversiteit en wordt gebruikt voor zowel signalering, beleidsevaluatie en (nationale) verkenningen. Resultaten worden geaggregeerd tot indicatoren die aansluiten op het Nederlandse en Europese beleid. In deze rapportage worden alle facetten beschreven van het model die nodig zijn om de kwaliteitsstatus A voor modellen van de WOT Natuur & Milieu te verkrijgen. De MNP zal de komende jaren verder ontwikkeld en onderbouwd worden.