Species richness estimates from accumulation and rarefaction curves at <i>n</i> = 500 specimens.

Species richness values calculated from accumulation curves (Sn.a; grey solid line), individual-based rarefaction (E[Sn.r]; black solid line), and spatially explicit rarefaction (E[Sn.ser]; black dotted line) are shown for sampling units (at three spatial scales: 5 x 5 km, 50 x 50 km, and 100 x 100 km) included in four computer simulation experiments (A, B, C and D).