TY - JOUR
TI - Microbial Respiration of Organic Carbon in Freshwater Microcosms: The Potential for Improved Estimation of Microbial CO2 Emission from Organically Enriched Freshwater Ecosystems
AU - Anderson, O. Roger
TI - Microbial Respiration of Organic Carbon in Freshwater Microcosms: The Potential for Improved Estimation of Microbial CO2 Emission from Organically Enriched Freshwater Ecosystems
AB - Respiratory CO2 emissions from laboratory freshwater microcosms enriched with organic C (glucose and amino acids) and kept in the dark at 24°C were compared to control microcosms without C enrichment for two different freshwater pond sources. The purpose was to estimate experimentally the rate of respiratory CO2 emission from organically polluted freshwater ecosystems compared to non-enriched water. Experiment One, used pond water collected at the Lamont-Doherty Earth Observatory campus; and Experiment Two used pond water, inoculated with natural detritus, obtained from North Carolina. At peak respiration, the net efflux of CO2 (enriched minus control) to the atmosphere was ~ 90 nmol min–1 L–1 (Day 7, Experiment One) and ~ 240 nmol min–1 L–1 (Day 3, Experiment Two). The corresponding net efflux of C to the atmosphere was 25 nmol C min–1 L–1 (Day 7, Experiment One) and 65 nmol C min–1 L–1 (Day 3, Experiment Two). Peak CO2 emissions from the organic-enriched microcosms expressed as μmol m–2 s–1 (as more typically reported for natural bodies of water) were 0.20 for Experiment One, and 0.42 for Experiment Two, at a surface layer depth of approx. 20 cm, i.e. the microcosm depth. There was a relatively large correlation between respiratory CO2 emission and bacterial densities in the organic-C enriched microcosms (r = 0.76), but a smaller correlation (r = 0.32) in the non-enriched, control microcosm. Further broad scale research, robustly sampling natural bodies of organically polluted water, is needed to confirm and better establish the results of the research reported here using microcosms.
VL - 2016
IS - Volume 55, Issue 3
PY - 2016
SN - 0065-1583
C1 - 1689-0027
SP - 189
EP - 196
DO - 10.4467/16890027AP.16.018.5750
UR - https://ejournals.eu/en/journal/acta-protozoologica/article/microbial-respiration-of-organic-carbon-in-freshwater-microcosms-the-potential-for-improved-estimation-of-microbial-co2-emission-from-organically-enriched-freshwater-ecosystems
KW - Aquatic microbial CO2 emissions
KW - atmospheric CO2
KW - climate change
KW - environmental change
KW - organic aquatic pollution
KW - protists