Planten als indicatoren voor pH en GVG : Een vergelijking van het ITERATIO- en Wamelink-indicatorsysteem voor pH en GVG
Hennekens, Stephan; Holtland, Jan; Rooijen, Nils van; Wamelink, Wieger; Ozinga, Wim
The Netherlands Environmental Assessment Agency, WOT/WENR, Statistics Netherlands and the provincial authorities use indicators to identify and measure the status and trends in environmental parameters, such as plant nutrient availability, soil pH and the average groundwater levels in spring. In 2020 WENR and Jan Holtland (Holtland Advies) carried out a comparative study of indicator systems focusing on plant nutrient availability. In the present study, in addition to the ITERATIO and WW systems, use is made of the Ellenberg indicator system for Central Europe as a reference against which to compare ITERATIO and WW values; all other analyses that have been carried out are direct comparisons of the differences between ITERATIO and WW. This report also contains a concise background description of the three systems. The research question for the study is: How can the differences between the values for the environmental parameters calculated in the ITERATIO and WW systems be explained, and what are the consequences for the application of these systems for identifying national trends in soil pH and average groundwater levels in spring.