Link between NABO and the Swiss Biodiversity Monitoring BDM
Total Swiss grid sampling of the topsoil
As part of indicator Z9 «Biodiversity in habitats» of the Biodiversity Monitoring Switzerland BDM. Periodic plant physiological assessments are carried out at a total of around 1,200 sites. Between 2011 and 2015, soil samples at 0 to 20 cm depth were collected and processed in the laboratory of NABO and analysed for different soil properties (Fig. 1). Thus, for the first time in Switzerland, both plant physiological assessments and soil samples from the same locations are available nationwide at that spatial resolution. This will fill an significant gap in the biodiversity monitoring programme.
Figure 1: Overview of Z9 sites with soil samples
On the one hand, surveys of vascular plants, mosses and molluscs can now be related directly to soil parameters such as pH, carbon content, bulk density, etc., and interpreted accordingly.
On the other hand, the joint project NABO-BDM yields for the first time a uniform nationwide Swiss collection of soil samples. This collection is characterised by a large sample size and an adequate representation of the area, thus offering enormous potential for national and regional assessments. The archived fine soil samples and the separately assessed coarse soil material (gravel and rocks) are available for further analyses to address various issues.
The synchronised sampling of various environmental compartments provides high synergetic benefits at relatively low extra costs. The results represent a mutual added value for the interpretation of the individual data.
In addition to the analyzes of the soil parameters already carried out, the interpretation of DNA sequencing and the analysis of trace elements is currently underway (Fig. 2).
Figure 2: Conceptual linking of the vascular plant, moss and mollusc recordings with the topsoil samples.
First results show that there is a good correlation between pH and the average reaction values according to Landolt at sites with at least three plant types per site (Fig. 3).
Figure 3: Scatterplot of pH against R-values according Landolt et al. (Meuli et al. 2017)
