Additive decomposition of species richness for (a) major data sets and (b) arthropod guilds.

(a) Major data sets (estimated species richness with ten protocols, observed species richness with ten protocols, estimated species richness with FITs, observed species richness with FITs, 885 common and rare species, inset: flowering trees (note the different scale). (b) Arthropod guilds (observed species richness with ten protocols). Species richness is partitioned among alpha (black bars), betaT (grey bars), betaH (stippled bars) and betaV (white bars). * indicates that parameters are significantly different from zero. Randomization tests were not performed with estimated species richness.