VSD+ PROPS Luc Bonten, Janet Mol, Wieger Wamelink, Gert Jan Reinds, Jan-Cees Voogd

Contents  VSD+, what is new  PROPS ● What is PROPS ● Extension of number of species in PROPS ● Limit number of species in PROPS calculations  VSD+ PROPS

What is new in VSD+  option for calcareous soils ● no Ca and Mg weathering ● no cation exchange ● new parameter: parentCa (<0 for non-calcareous, 1 for CaCO 3, 0 for MgCO 3 )  new organic C model: RothC ● N mineralisation linked to C turnover ● new parameters: o rfmiR (also in MetHyd o QIlf (0.25 for forest, 0.67 for grassland)

1. What is PROPS PROPS  model that calculates the chance (probability) that a plant species is present  based on measurable abiotic conditions Derived from:  relevés with simultaneously measured abiotic conditions (N, pH)  climate data

Relevés with abiotic measurements  4596 relevés in Netherlands, Austria and Ireland  pH and N (N-total, C/N ratio and/or NO 3 )  519 species that were found ≥ 25 relevés

Relevés with measurements of abiotic conditions

Response functions 2 dimensional response functions:  pH  N (N-total, CN, NO 3 ) logit(y) = α + β 1 pH + β 2 N + γ 1 pH 2 + γ 2 N 2 + δpH·N probability = 1/(1+exp(-logit(y))

Fitting of response functions

Example: Atriplex prostrata

Example: Calluna vulgaris

Results Number of plant species with response functions  pH + N-total:406  pH + CN ratio:330  pH + NO 3 :146

2. Extension number of species Problem:  only few relevés where abiotic conditions have been measured  response functions for few species  how to get abiotic conditions for other relevés? Datasets:  ‘Abiotic’ dataset: ± 4600 relevés with measurements of abiotic conditions  Bioscore dataset: ± 430,000 relevés without abiotic conditions

Bioscore dataset

methodology to include more species in PROPS  2 step approach: Step 1. estimate abiotic conditions based on presence of plant species with known response functions Step 2. derive response functions based on estimated abiotic conditions

relevé Sp1 Sp6 SP20 Sp78 Sp145 Sp221 Sp456 estimation of abiotic conditions ‘Abiotic’ dataset (± 400 species, response for pH and N) Sp1 Sp2 | Spn Bioscore dataset (430,000 relevés, ± 4,000 species) Sp1 Sp2 | Spx relevé Sp1 Sp6 SP20 Sp78 Sp145 Sp221 Sp456 species that in Bioscore with response functions in ‘Abiotic’ dataset estimate pH and N from species with response functions (at least 5 species from ‘abiotic’ dataset)

estimation of abiotic conditions

Bioscore dataset with abiotic conditions

Validation

Fitting response functions 4 dimensional response functions:  pH  N  temperature  precipitation

Results Number of plant species with response functions ‘abiotic’ database  pH + N-total:406  pH + CN ratio:330  pH + NO 3 :146 Bioscore database  pH + N-total:2306  pH + CN ratio:2309  pH + NO 3 :1781

3. Preselect species in PROPS calculations  2300 species with response functions  a-priori selection of species is required  EUNIS classification is used in M&M work  species selection related to EUNIS

 overlay of EUNIS map (level 2; e.g. B1) with Map for the Natural Vegetation for Europe.  this gives per level 2 EUNIS class all possible vegetation types  combine overlay with list of Level 3 EUNIS classes (e.g. B1.1)  Wieger screened the remaining 7000 (!) combinations Step 1:Overlaying

Step 2: species assignment  For each unit of the EuroVegMap units we got a list of typical/relevant species  These can be linked to the PROPS list

In VSD+Studio it is implemented as follows:

Species options

Summary PROPS  response functions (pH, N, T, prec.) for 2300 species  a-priori selection of species based on vegetation type  relatively few species for Scandinavia, Iberic peninsula, south-east of Europe

Thanks (VSD+ PROPS training session on wednesday afternoon)