Data, code, and figures associated with Kelp forest dynamics controlled by substrate complexity in PNAS investigating how substrate complexity -- the rugosity of the underlying seafloor -- associates with 38 years of kelp forest community dynamics from six sites around San Nicolas Island (SNI) off the coast of Southern California.
Multivariate analyses of 14 macroalgae and invertebrate species indicate SNI kelp forests exhibit three distinct community states: an algae-dominated transient state where sea urchins are absent, a mixed state where kelp and urchins coexist, and a barren state where active urchin grazing inhibits kelp recovery. High velocity, abrupt shifts in state are observed at sites exhibiting low complexity, whereas high rugosity sites and transects exhibited 38 years of resilient kelp forest persistence.
