Southern California Respiration Quotient Controls

Southern California Bight coastal waters are dynamic and strongly influenced by a changing climate. An increased respiration quotient has been found during high temperature and low nitrogen conditions. These observations are specific to open ocean conditions, and their applicability to coastal environments is uncertain. To disentangle the controlling factors in a coastal environment, we examined environmental conditions, particulate organic matter, and the respiration quotient over five years in the Southern California Bight. Our study revealed clear seasonal variation in environmental conditions and biological parameters. We detected higher than previously reported respiration quotient ratios. We found a strong inverse relationship between respiration quotient, nitrate and chlorophyll. Our findings also suggest that changes in community structure, triggered by nutrient shifts and a local oil spill, affected the range in respiration quotient and explains some of the variability measured. Coastal environments are more complicated than open ocean measurements, with wider implications. 

Speaker: Allison Moreno, Assistant Professor, University of California, Santa Cruz

Attend in person or click here to watch on Zoom