1. Arjen van Hinsberg, Janet Mol 8-4-2014 1 Dynamic modelling of impacts in Natura 2000 habitats the Dutch response to the call for data

2. 2 Content Ambitions & Methods Results & Problems Conclusions

3. Ambition  Create a small set of regional representative sites which could be used to model effects of deposition on biodiversity  Create a policy relevant biodiversity endpoint  Use VSD+/Props Arjen van Hinsberg 08-04-2013 3

4. Selection of Sites 1(2)  Policy relevant: Natura 2000 –50% of the Dutch Nature Area’s –51 Habitats out of 251  Sensitive to atmospheric deposition –Critical loads ranging from 5 kg/ha/yr – 35 kg/ha/yr –45 Habitats –No marine or aquatic habitats  Regional representative: Focus on larger Habitats Arjen van Hinsberg 08-04-2013 4

5. Selection of sites 2(2) Arjen van Hinsberg 08-04-2013 5 SizeNo Habitat types TotalSensitiveSelected Very small (<100 ha)88 Small (100-400 ha)86 Average (400-1600 ha)14 2 Large (1600-6400 ha)10 5 Very large (>6400 ha)1276 Total514513 Various EUNIS types >70% of sensitive habitat area

6. 13 Habitats (& 5 sub types) 6 (1) Dry heath (2) Grey Dunes With variation within EUNIS A2.54 B1.3/4/5 D1/2 E1.94 F4.2/11 G1.5/6/8

7. VSD+ runs Plan for each habitat: 1.Select a site with average exceedance levels 2.Run 3 Scenarios: –Current Levels –Gothenburg –Background 3.expand number of sites: both a low and high exceedance level 7

8. VSD Parametrization ‘Characteristic’ conditions:  Soil parameterization based on SMART-soil types  Vegetation type specific litterfall based on SUMO  Habitat specific seepage and groundwater levels  Site specific soil measurement when available 8

9. Biodiversity endpoint based on policy targets List of target (typical) species or List characteristic species Favourable status: High quality - List of competing species Low quality Arjen van Hinsberg 08-04-2013 9 List of species at high Habitat quality

10. Calculating Endpoint 10 Chance of occurrence Chance of occurrence Maximum chance Averaged over species PROPS for 80% species Suitability = Overall Suitability for high quality =

11. Examples Arjen van Hinsberg 08-04-2013 11 Plausible trend Historic situation ok?

12. Similar trends at species level Arjen van Hinsberg 08-04-2013 12

13. Similar trends in more sensitive habitats Arjen van Hinsberg 08-04-2013 13

14. Overall relationship: Suitability decreases with exceedance Arjen van Hinsberg 08-04-2013 14 Each point: Modelrun of 2050 for a given scenario & habitat R2 = 0,68

15. Response  Problems with wetlands, salt wetlands (A2.52), calcareous soils  3 scenarios runs for 6 habitat types  Various EUNIS types (B1.3/D1,2/F4.2/G1.5,8) Arjen van Hinsberg 08-04-2013 15

16. Conclusions Arjen van Hinsberg 08-04-2013 16

17. Conclusions  Methodology works: a representative data set could be delivered –Habitat community could deliver information on targets, maps etc –PROPS available for most (80%) of the ‘high quality’ species –VSD+ can run for different habitat types  Suitability Index for High Quality is useful –Policy relevant, simple & based on targets –Reference is easy –Sensitive for deposition  However: –Ambitions not realized: we didn’t deliver a representative dataset Arjen van Hinsberg 08-04-2013 17

18. Wishes  We need to improve VSD-parameterization and model more habitat types –wetlands (C, C/N), calcareous soils  We need to improve PROPS with respect to Nitrogen effects –NO3- alone doesn’t tell the hole story  We need better parameterization in historic/low deposition conditions (information from other NFC’s?)  We need to be clear about our model results: –Not only ‘No net loss’ also: high quality –Biological recovery time isn’t modelled!! Often ecological recovery will be needed.  Arjen van Hinsberg 08-04-2013 18