It is well understood that differences in the cues used by consumers and their resources in fluctuating environments can give rise to trophic mismatches governing the emergent effects of global change. Trophic mismatches caused by changes in consumer energetics during periods of low resource availability have received far less attention, although this may be common for consumers during winter when primary producers are limited by light. Even less is understood about these dynamics in marine ecosystems, where consumers must cope with energetically costly changes in CO2‐driven carbonate chemistry that will be most pronounced in cold temperatures. This may be especially important for calcified marine herbivores, such as the pinto abalone (
Aseptic technique has historically served as a fundamental practice in microbiology, helping to maintain culture purity and integrity. This technique has been widely encouraged and employed for use with cultures of heterotrophic bacteria as well as freshwater and marine algae. Yet, recent observations have suggested that these approaches may bring their own influences. We observed variations in growth among replicate experimental cyanobacterial cultures upon flaming of the culture tube opening during sample transfer and collection. Investigation revealed the pH of culture media had decreased from the initial pH established during media preparation. Flaming of sterile culture media alone confirmed a significant decrease, by as much as 1.7 pH units, and correlated with increased flaming events over time. We hypothesized that the causative factor was the introduction of carbon dioxide (CO2) into the media. To test this hypothesis, qualitative and quantitative analyses were used to determine the primary driver of pH decline. We further assessed the direct effects of flaming and subsequent pH changes on
- Award ID(s):
- 1840715
- NSF-PAR ID:
- 10458047
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 18
- Issue:
- 5
- ISSN:
- 1541-5856
- Page Range / eLocation ID:
- p. 211-219
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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