The basic problem with biodiversity indicators is that biodiversity is a concept with various aspects, which all require their own indicators. They often show no or even negative correlation, so simply adding them up yields little information. The solution are baskets of indicators within the same anthropocentric value system, which form an index similar to the Dow Jones Index. Even within such a basket with a set of indicators of concordant values, the single indicators may not correlate (e.g. red list species of snails vs. butterflies), but they both indicate the same value system (e.g. species conservation) and therefore can be cumulated.

For agricultural landscapes in industrialised countries, the main value systems concerning biodiversity are conservation (of rare and threatened species or breeds), ecological resilience (against local impacts and global change), and biological control (of pest organisms).

The best indicators are linear correlates of the biodiversity aspect or entity to be assessed. A tedious but unavoidable two step approach is proposed to find and test reliable and affordable indicator sets for the main value systems conservation, ecological resilience, and biological control.