title: Comment on "Global resilience of tropical forest and savanna to critical transitions".
abstract: Hirota et al. (Reports, 14 October 2011, p. 232) used spatial data to show that grasslands, savannas, and forests represent opposing stable states. Reanalyzing their data and drawing from temporal studies, we argue that spatial analyses underestimate the bistability of grasslands and savannas due to limitations of substituting space for time. We propose that temporal and spatial data are needed to predict critical transitions between grasslands and savannas.
authors.affiliation: Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66506, USA. zarata@ksu.edu
authors.forename: Zak
authors.initials: Z
authors.lastname: Ratajczak
authors.forename: Jesse B
authors.initials: JB
authors.lastname: Nippert
mesh_terms: D017753:Ecosystem; D014197:Trees; D014329:Tropical Climate