A recent publication to come from some of the CLCR’s researchers has got me thinking on how biodiversity can be mapped and predicted across the Welland Catchment.
This post just captures some of my initial thoughts so that I can come back to them later. Bush et al. (2017) discuss an approach to converting point samples of species to continuous maps of alpha diversity (amongst other variables) using an approach they term CEOBE (connecting earth observation to biodiversity and ecosystems).
Several things from this study jump out at me that might be appropriate to applying similar techniques to the Welland Catchment. My original plan is to model habitat quality and threat using the InVEST toolkit. Here the model is paramaterised based on:
- the suitability of a land cover / habitat to an individual or group of species (based on knowledge of that group, but still subjective)
- the distance from / potential risk of possible threats (again not an objective value)
While I can see this output having a use, it remains subjective.
What would be great is a continuous map of alpha diversity (say farmland specialist passerines) across the whole of the Welland Catchment based on spatially explicit RS and point based data. Potential inputs into the creation of this map might be:
- 1km gridded data from the BTO’s annual breeding bird survey; providing the point based species samples
- High resolution RS data on NDVI from DEFRA
- Gridded temperature and precipitation data
- High resolution land cover data from processed Sentinel-2 imagery
Modern statistical techniques allow site by species matrix biodiversity data to be combined with site by environmental variable matrix data (perhaps taken from remotely sensed data-sets) (Bush et al. 2017). These techniques include:
- joint species distribution models
- community-occupancy detection models
- generalised dissimilarity models
A baseline map of alpha diversity across the catchment would be an interesting baseline and could have useful applications to the project. Something for me to consider in more depth later…
Bush, A., Sollmann, R., Wilting, A., Bohmann, K., Cole, B., Balzter, H., Martius, C., Zlinszky, A., Calvignac-Spencer, S., Cobbold, C.A. and Dawson, T.P., 2017. Connecting Earth observation to high-throughput biodiversity data. Nature Ecology & Evolution.