Document Type

Data Set

Publication Date


Collection Date(s)

2022-06-01, 2022-07-23


Macroalgae form important coastal ecosystems and are considered to be highly

productive, yet individual macrophyte carbon uptake rates are

poorly documented and methodologies for in situ assessments of productivity

are not well developed. In this study, we employ a 13C enrichment method in

benthic chambers to calculate carbon uptake rates and assess d13C signatures of

a large stock of nearshore benthic macroalgae varying in taxa and morphology in

Southern California. Our objectives are to 1) identify the variability of carbon

uptake and inorganic carbon use among individuals of the same species or

morphology and speculate how macroalgae might respond to future changes in

ocean chemistry, and 2) establish accurate and accessible carbon uptake

procedures for coastal benthic primary producers. We found no significant

relationship between environmental factors such as nutrient concentrations,

PAR, temperature, salinity, and productivity rates, suggesting that unique

physiological complexions underpin the high variability of carbon uptake and

d13C in studied macrophyte samples. We consider three reasons our

experimental carbon uptake rates are 3–4 orders of magnitude lower than

existing literature, which reports carbon uptake in the same units despite using

different methods: 1) underrepresentation of Pmax, 2) incomplete carbon

fractionation corrections, and 3) reduced hydrodynamics within the

benthic chambers.

Grant Number

NSF DBI 1950350, NSF DEB 2312723

Grant Sponsor

National Science Foundation

Supplementary Datasheet #1.numbers (215 kB)

Supplementary Datasheet #2.numbers (154 kB)
Benthic Chamber Deployment Metadata