PROPS: Probability of Occurrence of Plant Species
Purpose of the tool
PROPS is a model that estimates the probability of occurrence of plant species based on abiotic factors, such as average annual temperature, precipitation, soil pH, nutrient availability or groundwater table. At the given soil or climatic data it can provide which plant species may occur. This tool can be used for scenario analysis involving climate change, land use change or changes in government policies.
The primary target group is the scientific community. However, in collaboration with the developers team it is possible to cooperate with governments and NGO’s.
PROPS may be applied on a site scale up to the European scale, depending on the data availability. However, on every scale and site specific data will be necessary. For each species in the model it will give the probability of occurrence or expected presence or absence. This can be done for all species or for a selection, e.g. red list species or Natura 2000 target species. The model can be used in combination with other models, e.g. a soil and vegetation model (VSD+ and SUMO) or a plant dispersal model (DIMO).
Future changes in biodiversity indexes for forests vary with climate and deposition scenario. If we assume constant climate (CON) and constant deposition (CD), the Czekanowski index, a measure for dissimilarity between two species compositions (using the year 2010 as the reference year), is close to one in 2050 for entire Europe. The fact that it is not always one shows that even with constant climate and deposition inputs, the soil pH changes between 2010 and 2050, indicating that soil pH is not always in equilibrium with the inputs in 2010. If we assume constant climate and CLE, the index decreases but only slightly: CLE depositions in 2050 are close to those in 2010. With MFR depositions, but constant climate, the Czekanowski index changes significantly, showing the effect of a strongly decreasing N deposition on species composition. If both climate and N deposition change, the Czekanowski index decreases sharply indicating that climate change in the PROPS model strongly changes occurrence probability in those areas with pronounced temperature change in 2050.
Maps of the median Chekanowski index per grid cell computed by the PROPS model for 2050 for CLE-CON, CLE-A1, MFR-CON and MFR-A1 scenario (left to right). Greenish colours indicate small changes in species occurrence, reddish and purple colours indicate large changes in species occurrence.
The figures give results for different scenarios, from left to right: constant climate and deposition, constant climate and slightly changing nitrogen deposition, constant climate and strongly decreasing nitrogen deposition and changing climate and decreasing nitrogen deposition.
The tool in practice
PROPS is still being developed for the Netherlands and Europe. It has been applied on both scales. For Europe it was used especially to assess the (combined) effects of climate change and nitrogen deposition.
Necessary inputs and conditions
Inputs for the model are soil abiotic parameters and climate data. There is a Dutch version of the model and a European version, with partly different plant species. If application outside these areas is requested the model has to be calibrated with vegetation data and soil and climate measurements (vegetation plots).
Wieger Wamelink, wieger.wamelink(at)wur.nl, Alterra, Wageningen UR
Phase and tool category: Strategy Development and Planning | Physical model
Spatial scale and time scale
PROPS is a point model, but it can be applied on any scale providing data availability.
Time scale: 50 years.
A European version of PROPS combined with the model VSD+ is being developed and will be available end 2014, including a user guide and a user friendly interface, through the contact person.
An installation file will be made available upon request.