Kelp systems dominate nearshore marine environments in upwelling zones characterized by cold temperatures and high nutrients. Worldwide, kelp population persistence and recruitment success generally decreases with rising water temperatures coupled with low nutrients, making kelp populations vulnerable to impending warming of the oceans. This response to climate change at a global scale, however, may vary due to regional differences in temperature variability, acclimation, and differential responses of kelp species to changing conditions. Culture experiments were conducted on 12 eastern Pacific kelp taxa across geographic regions (British Columbia, central California, and southern California) under three nitrate levels (1, 5, and 10 mu mol/L) and two temperatures (12 degrees C and 18 degrees C) to determine sporophyte production (i.e., recruitment success). For all taxa from all locations, sporophytes were always present in the 12 degrees C treatment and when recruitment failure was observed, it always occurred at 18 degrees C, regardless of nitrate level, indicating that temperature is the driving factor limiting recruitment, not nitrate. Rising ocean temperatures will undoubtedly cause recruitment failure for many kelp species; however, the ability of species to acclimatize or adapt to increased temperatures at the warmer edge of their species range may promote a resiliency of kelp systems to climate change at a global scale.
1.Moss Landing Marine Labs, 8272 Moss Landing Rd, Moss Landing, CA 95039 USA 2.Univ Rhode Isl, Coll Arts & Sci, Kingston, RI 02881 USA 3.Univ British Columbia, Dept Zool, Vancouver, BC V6T 1Z4, Canada 4.Univ Texas, Marine Sci Inst, 750 Channelview Dr, Port Aransas, TX 78373 USA
Recommended Citation:
Muth, Arley F.,Graham, Michael H.,Lane, Christopher E.,et al. Recruitment tolerance to increased temperature present across multiple kelp clades[J]. ECOLOGY,2019-01-01,100(3)