Effect of turf or crust on canopy Functional group Example mechanism Example citation
Competition Turfs Space limitation prevents canopy recruitment Dayton et al. 1984
Competition Turfs Abiotic disturbance (sedimentation, eutrophication) favors the growth of opportunistic turfs, which outcompete canopy-forming species Reviewed in Filbee-Dexter & Wernberg 2018
Competition Coralline crusts Epithelial sloughing of coralline surface cells prevents recruitment and establishment of canopy-forming species Reviewed in McCoy and Kamenos 2013
Facilitation Coralline turfs Coralline turfs ameliorate desiccation stress in canopy algae Hutto 2011
Facilitation Turfs Understory algae provide refuge from herbivory for canopy recruits Harris et al. 1984