Early life stages of marine organisms are predicted to be vulnerable to ocean acidification. For macroalgae, reproduction and population persistence rely on spores to settle, adhere and continue the algal life cycle, yet the effect of ocean acidification on this critical life stage has been largely overlooked. We explicitly tested the biomechanical impact of reduced
Non‐calcified marine macroalgae (“seaweeds”) play a variety of key roles in the modern Earth system, and it is likely that they were also important players in the geological past, particularly during critical transitions such as the Cambrian Explosion (
- NSF-PAR ID:
- 10028545
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Geobiology
- Volume:
- 15
- Issue:
- 4
- ISSN:
- 1472-4677
- Page Range / eLocation ID:
- p. 588-616
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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pH on early spore adhesion. We developed a shear flume to examine the effect of reducedpH on spore attachment time and strength in two intertidal rhodophyte macroalgae, one calcified (Corallina vancouveriensis ) and one noncalcified (Polyostea robusta ). ReducedpH delayed spore attachment of both species by 40%–52% and weakened attachment strength inC. vancouveriensis , causing spores to dislodge at lower flow‐induced shear forces, but had no effect on the attachment strength ofP. robusta . Results are consistent with our prediction that reducedpH disrupts proper curing and gel formation of spore adhesives (anionic polysaccharides and glycoproteins) via protonation and cation displacement, although experimental verification is needed. Our results demonstrate that ocean acidification negatively, and differentially, impacts spore adhesion in two macroalgae. If results hold in field conditions, reduced oceanpH has the potential to impact macroalgal communities via spore dysfunction, regardless of the physiological tolerance of mature thalli. -
Abstract The leaf economic spectrum is a widely studied axis of plant trait variability that defines a trade‐off between leaf longevity and productivity. While this has been investigated at the global scale, where it is robust, and at local scales, where deviations from it are common, it has received less attention at the intermediate scale of plant functional types (
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Abstract Aim To test the latitudinal gradient in plant species diversity for self‐similarity across taxonomic scales and amongst taxa.
Location North America.
Methods We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the latitudinal gradients in species diversity (
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